xref: /btstack/src/hci.c (revision 098c2716f181805b30dd979c640d4a84dde96da4)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BLUEKITCHEN
24  * GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef ENABLE_BLE
57 #include "gap.h"
58 #include "ble/le_device_db.h"
59 #endif
60 
61 #include <stdarg.h>
62 #include <string.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "bluetooth_company_id.h"
70 #include "bluetooth_data_types.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 #include "ad_parser.h"
76 
77 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
78 #ifndef HCI_HOST_ACL_PACKET_NUM
79 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
80 #endif
81 #ifndef HCI_HOST_ACL_PACKET_LEN
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
83 #endif
84 #ifndef HCI_HOST_SCO_PACKET_NUM
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_LEN
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
89 #endif
90 #endif
91 
92 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
93 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
98 #endif
99 
100 #define HCI_CONNECTION_TIMEOUT_MS 10000
101 
102 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
103 #define HCI_RESET_RESEND_TIMEOUT_MS 200
104 #endif
105 
106 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
107 #ifndef GAP_INQUIRY_MAX_NAME_LEN
108 #define GAP_INQUIRY_MAX_NAME_LEN 32
109 #endif
110 
111 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
112 #define GAP_INQUIRY_DURATION_MIN       0x01
113 #define GAP_INQUIRY_DURATION_MAX       0x30
114 #define GAP_INQUIRY_MIN_PERIODIC_LEN_MIN 0x02
115 #define GAP_INQUIRY_MAX_PERIODIC_LEN_MIN 0x03
116 #define GAP_INQUIRY_STATE_IDLE         0x00
117 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
118 #define GAP_INQUIRY_STATE_ACTIVE       0x81
119 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
120 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
121 #define GAP_INQUIRY_STATE_PERIODIC     0x84
122 #define GAP_INQUIRY_STATE_W2_EXIT_PERIODIC 0x85
123 
124 // GAP Remote Name Request
125 #define GAP_REMOTE_NAME_STATE_IDLE 0
126 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
127 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
128 
129 // GAP Pairing
130 #define GAP_PAIRING_STATE_IDLE                       0
131 #define GAP_PAIRING_STATE_SEND_PIN                   1
132 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
133 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
134 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
135 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
136 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
137 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
138 
139 //
140 // compact storage of relevant supported HCI Commands.
141 // X-Macro below provides enumeration and mapping table into the supported
142 // commands bitmap (64 bytes) from HCI Read Local Supported Commands
143 //
144 
145 // format: command name, byte offset, bit nr in 64-byte supported commands
146 // currently stored in 32-bit variable
147 #define SUPPORTED_HCI_COMMANDS \
148     X( SUPPORTED_HCI_COMMAND_READ_REMOTE_EXTENDED_FEATURES         ,  2, 5) \
149     X( SUPPORTED_HCI_COMMAND_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE , 10, 4) \
150     X( SUPPORTED_HCI_COMMAND_READ_BUFFER_SIZE                      , 14, 7) \
151     X( SUPPORTED_HCI_COMMAND_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING, 18, 3) \
152     X( SUPPORTED_HCI_COMMAND_READ_ENCRYPTION_KEY_SIZE              , 20, 4) \
153     X( SUPPORTED_HCI_COMMAND_SET_EVENT_MASK_PAGE_2                 , 22, 2) \
154     X( SUPPORTED_HCI_COMMAND_WRITE_LE_HOST_SUPPORTED               , 24, 6) \
155     X( SUPPORTED_HCI_COMMAND_REMOTE_OOB_EXTENDED_DATA_REQUEST_REPLY, 32, 1) \
156     X( SUPPORTED_HCI_COMMAND_WRITE_SECURE_CONNECTIONS_HOST         , 32, 3) \
157     X( SUPPORTED_HCI_COMMAND_READ_LOCAL_OOB_EXTENDED_DATA_COMMAND  , 32, 6) \
158     X( SUPPORTED_HCI_COMMAND_LE_WRITE_SUGGESTED_DEFAULT_DATA_LENGTH, 34, 0) \
159     X( SUPPORTED_HCI_COMMAND_LE_SET_ADDRESS_RESOLUTION_ENABLE      , 35, 1) \
160     X( SUPPORTED_HCI_COMMAND_LE_READ_MAXIMUM_DATA_LENGTH           , 35, 3) \
161     X( SUPPORTED_HCI_COMMAND_LE_SET_DEFAULT_PHY                    , 35, 5) \
162     X( SUPPORTED_HCI_COMMAND_LE_SET_EXTENDED_ADVERTISING_ENABLE    , 36, 6) \
163     X( SUPPORTED_HCI_COMMAND_LE_READ_BUFFER_SIZE_V2                , 41, 5) \
164     X( SUPPORTED_HCI_COMMAND_SET_MIN_ENCRYPTION_KEY_SIZE           , 45, 7) \
165 
166 // enumerate supported commands
167 #define X(name, offset, bit) name,
168 enum {
169     SUPPORTED_HCI_COMMANDS
170     SUPPORTED_HCI_COMMANDS_COUNT
171 };
172 #undef X
173 
174 // prototypes
175 #ifdef ENABLE_CLASSIC
176 static void hci_update_scan_enable(void);
177 static void hci_emit_discoverable_enabled(uint8_t enabled);
178 static int  hci_local_ssp_activated(void);
179 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
180 static bool hci_ssp_supported(hci_connection_t * connection);
181 static void hci_notify_if_sco_can_send_now(void);
182 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
183 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
184 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
185 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
186 static void hci_connection_timestamp(hci_connection_t *connection);
187 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
188 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
189 #endif
190 
191 static int  hci_power_control_on(void);
192 static void hci_power_control_off(void);
193 static void hci_state_reset(void);
194 static void hci_halting_timeout_handler(btstack_timer_source_t * ds);
195 static void hci_emit_transport_packet_sent(void);
196 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
197 static void hci_emit_nr_connections_changed(void);
198 static void hci_emit_hci_open_failed(void);
199 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
200 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
201 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
202 static void hci_run(void);
203 static int  hci_is_le_connection(hci_connection_t * connection);
204 
205 #ifdef ENABLE_CLASSIC
206 static int hci_have_usb_transport(void);
207 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection);
208 #endif
209 
210 #ifdef ENABLE_BLE
211 static void hci_whitelist_free(void);
212 #ifdef ENABLE_LE_CENTRAL
213 // called from test/ble_client/advertising_data_parser.c
214 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
215 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
216 static hci_connection_t * gap_get_outgoing_connection(void);
217 static void hci_le_scan_stop(void);
218 static bool hci_run_general_gap_le(void);
219 #endif
220 #ifdef ENABLE_LE_PERIPHERAL
221 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
222 static void hci_periodic_advertiser_list_free(void);
223 static le_advertising_set_t * hci_advertising_set_for_handle(uint8_t advertising_handle);
224 #endif /* ENABLE_LE_EXTENDED_ADVERTISING */
225 #endif /* ENABLE_LE_PERIPHERAL */
226 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
227 static uint8_t hci_iso_stream_create(hci_con_handle_t cis_handle);
228 static void hci_iso_stream_finalize(hci_iso_stream_t * iso_stream);
229 static hci_iso_stream_t * hci_iso_stream_for_cis_handle(hci_con_handle_t cis_handle);
230 static void hci_iso_stream_requested_finalize(void);
231 static void hci_iso_stream_requested_confirm(void);
232 static void hci_iso_packet_handler(uint8_t * packet, uint16_t size);
233 #endif /* ENABLE_LE_ISOCHRONOUS_STREAMS */
234 #endif /* ENABLE_BLE */
235 
236 // the STACK is here
237 #ifndef HAVE_MALLOC
238 static hci_stack_t   hci_stack_static;
239 #endif
240 static hci_stack_t * hci_stack = NULL;
241 
242 #ifdef ENABLE_CLASSIC
243 // default name
244 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
245 
246 // test helper
247 static uint8_t disable_l2cap_timeouts = 0;
248 #endif
249 
250 // reset connection state on create and on reconnect
251 // don't overwrite addr, con handle, role
252 static void hci_connection_init(hci_connection_t * conn){
253     conn->authentication_flags = AUTH_FLAG_NONE;
254     conn->bonding_flags = 0;
255     conn->requested_security_level = LEVEL_0;
256 #ifdef ENABLE_CLASSIC
257     conn->request_role = HCI_ROLE_INVALID;
258     conn->sniff_subrating_max_latency = 0xffff;
259     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
260     conn->link_key_type = INVALID_LINK_KEY;
261     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
262     btstack_run_loop_set_timer_context(&conn->timeout, conn);
263     hci_connection_timestamp(conn);
264 #endif
265     conn->acl_recombination_length = 0;
266     conn->acl_recombination_pos = 0;
267     conn->num_packets_sent = 0;
268 
269     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
270 #ifdef ENABLE_BLE
271     conn->le_phy_update_all_phys = 0xff;
272 #endif
273 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
274     conn->le_max_tx_octets = 27;
275 #endif
276 #ifdef ENABLE_CLASSIC_PAIRING_OOB
277     conn->classic_oob_c_192 = NULL;
278     conn->classic_oob_r_192 = NULL;
279     conn->classic_oob_c_256 = NULL;
280     conn->classic_oob_r_256 = NULL;
281 #endif
282 }
283 
284 /**
285  * create connection for given address
286  *
287  * @return connection OR NULL, if no memory left
288  */
289 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
290     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
291 
292     hci_connection_t * conn = btstack_memory_hci_connection_get();
293     if (!conn) return NULL;
294     hci_connection_init(conn);
295 
296     bd_addr_copy(conn->address, addr);
297     conn->address_type = addr_type;
298     conn->con_handle = HCI_CON_HANDLE_INVALID;
299     conn->role = HCI_ROLE_INVALID;
300 
301     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
302 
303     return conn;
304 }
305 
306 
307 /**
308  * get le connection parameter range
309 *
310  * @return le connection parameter range struct
311  */
312 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
313     *range = hci_stack->le_connection_parameter_range;
314 }
315 
316 /**
317  * set le connection parameter range
318  *
319  */
320 
321 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
322     hci_stack->le_connection_parameter_range = *range;
323 }
324 
325 /**
326  * @brief Test if connection parameters are inside in existing rage
327  * @param conn_interval_min (unit: 1.25ms)
328  * @param conn_interval_max (unit: 1.25ms)
329  * @param conn_latency
330  * @param supervision_timeout (unit: 10ms)
331  * @return 1 if included
332  */
333 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
334     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
335     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
336 
337     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
338     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
339 
340     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
341     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
342 
343     return 1;
344 }
345 
346 /**
347  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
348  * @note: default: 1
349  * @param max_peripheral_connections
350  */
351 #ifdef ENABLE_LE_PERIPHERAL
352 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
353     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
354 }
355 #endif
356 
357 /**
358  * get hci connections iterator
359  *
360  * @return hci connections iterator
361  */
362 
363 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
364     btstack_linked_list_iterator_init(it, &hci_stack->connections);
365 }
366 
367 /**
368  * get connection for a given handle
369  *
370  * @return connection OR NULL, if not found
371  */
372 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
373     btstack_linked_list_iterator_t it;
374     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
375     while (btstack_linked_list_iterator_has_next(&it)){
376         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
377         if ( item->con_handle == con_handle ) {
378             return item;
379         }
380     }
381     return NULL;
382 }
383 
384 /**
385  * get connection for given address
386  *
387  * @return connection OR NULL, if not found
388  */
389 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
390     btstack_linked_list_iterator_t it;
391     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
392     while (btstack_linked_list_iterator_has_next(&it)){
393         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
394         if (connection->address_type != addr_type)  continue;
395         if (memcmp(addr, connection->address, 6) != 0) continue;
396         return connection;
397     }
398     return NULL;
399 }
400 
401 #ifdef ENABLE_CLASSIC
402 
403 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
404     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
405 }
406 
407 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
408     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
409 }
410 
411 #ifdef ENABLE_SCO_OVER_HCI
412 static int hci_number_sco_connections(void){
413     int connections = 0;
414     btstack_linked_list_iterator_t it;
415     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
416     while (btstack_linked_list_iterator_has_next(&it)){
417         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
418         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
419         connections++;
420     }
421     return connections;
422 }
423 #endif
424 
425 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
426     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
427 #ifdef HAVE_EMBEDDED_TICK
428     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
429         // connections might be timed out
430         hci_emit_l2cap_check_timeout(connection);
431     }
432 #else
433     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
434         // connections might be timed out
435         hci_emit_l2cap_check_timeout(connection);
436     }
437 #endif
438 }
439 
440 static void hci_connection_timestamp(hci_connection_t *connection){
441 #ifdef HAVE_EMBEDDED_TICK
442     connection->timestamp = btstack_run_loop_embedded_get_ticks();
443 #else
444     connection->timestamp = btstack_run_loop_get_time_ms();
445 #endif
446 }
447 
448 /**
449  * add authentication flags and reset timer
450  * @note: assumes classic connection
451  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
452  */
453 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
454     bd_addr_t addr;
455     reverse_bd_addr(bd_addr, addr);
456     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
457     if (conn) {
458         connectionSetAuthenticationFlags(conn, flags);
459         hci_connection_timestamp(conn);
460     }
461 }
462 
463 static bool hci_pairing_active(hci_connection_t * hci_connection){
464     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
465 }
466 
467 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
468     if (hci_pairing_active(hci_connection)) return;
469     if (ssp){
470         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
471     } else {
472         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
473     }
474     // if we are initiator, we have sent an HCI Authenticate Request
475     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
476 
477     // if we are responder, use minimal service security level as required level
478     if (!initiator){
479         hci_connection->requested_security_level = (gap_security_level_t) btstack_max((uint32_t) hci_connection->requested_security_level, (uint32_t) hci_stack->gap_minimal_service_security_level);
480     }
481 
482     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
483 
484     uint8_t event[12];
485     event[0] = GAP_EVENT_PAIRING_STARTED;
486     event[1] = 10;
487     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
488     reverse_bd_addr(hci_connection->address, &event[4]);
489     event[10] = (uint8_t) ssp;
490     event[11] = (uint8_t) initiator;
491     hci_emit_event(event, sizeof(event), 1);
492 }
493 
494 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
495     hci_connection->requested_security_level = LEVEL_0;
496     if (!hci_pairing_active(hci_connection)) return;
497     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
498 #ifdef ENABLE_CLASSIC_PAIRING_OOB
499     hci_connection->classic_oob_c_192 = NULL;
500     hci_connection->classic_oob_r_192 = NULL;
501     hci_connection->classic_oob_c_256 = NULL;
502     hci_connection->classic_oob_r_256 = NULL;
503 #endif
504     log_info("pairing complete, status %02x", status);
505 
506     uint8_t event[11];
507     event[0] = GAP_EVENT_PAIRING_COMPLETE;
508     event[1] = 9;
509     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
510     reverse_bd_addr(hci_connection->address, &event[4]);
511     event[10] = status;
512     hci_emit_event(event, sizeof(event), 1);
513 
514     // emit dedicated bonding done on failure, otherwise verify that connection can be encrypted
515     if ((status != ERROR_CODE_SUCCESS) && ((hci_connection->bonding_flags & BONDING_DEDICATED) != 0)){
516         hci_connection->bonding_flags &= ~BONDING_DEDICATED;
517         hci_connection->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
518         hci_connection->bonding_status = status;
519     }
520 }
521 
522 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
523     hci_connection_t * conn = hci_connection_for_handle(handle);
524     if (!conn) return false;
525     return hci_pairing_active(conn);
526 }
527 
528 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
529     if (!hci_stack->link_key_db) return;
530     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
531     hci_stack->link_key_db->delete_link_key(addr);
532 }
533 
534 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
535     if (!hci_stack->link_key_db) return;
536     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
537     hci_stack->link_key_db->put_link_key(addr, link_key, type);
538 }
539 
540 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
541 	if (!hci_stack->link_key_db) return false;
542 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
543 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
544 	return result;
545 }
546 
547 void gap_delete_all_link_keys(void){
548     bd_addr_t  addr;
549     link_key_t link_key;
550     link_key_type_t type;
551     btstack_link_key_iterator_t it;
552     int ok = gap_link_key_iterator_init(&it);
553     if (!ok) {
554         log_error("could not initialize iterator");
555         return;
556     }
557     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
558         gap_drop_link_key_for_bd_addr(addr);
559     }
560     gap_link_key_iterator_done(&it);
561 }
562 
563 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
564     if (!hci_stack->link_key_db) return 0;
565     if (!hci_stack->link_key_db->iterator_init) return 0;
566     return hci_stack->link_key_db->iterator_init(it);
567 }
568 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
569     if (!hci_stack->link_key_db) return 0;
570     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
571 }
572 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
573     if (!hci_stack->link_key_db) return;
574     hci_stack->link_key_db->iterator_done(it);
575 }
576 #endif
577 
578 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
579     switch (address_type){
580         case BD_ADDR_TYPE_LE_PUBLIC:
581         case BD_ADDR_TYPE_LE_RANDOM:
582         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
583         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
584             return true;
585         default:
586             return false;
587     }
588 }
589 
590 static int hci_is_le_connection(hci_connection_t * connection){
591     return hci_is_le_connection_type(connection->address_type);
592 }
593 
594 /**
595  * count connections
596  */
597 static int nr_hci_connections(void){
598     int count = 0;
599     btstack_linked_item_t *it;
600     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
601         count++;
602     }
603     return count;
604 }
605 
606 uint16_t hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
607 
608     unsigned int num_packets_sent_classic = 0;
609     unsigned int num_packets_sent_le = 0;
610 
611     btstack_linked_item_t *it;
612     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
613         hci_connection_t * connection = (hci_connection_t *) it;
614         if (hci_is_le_connection(connection)){
615             num_packets_sent_le += connection->num_packets_sent;
616         }
617         if (connection->address_type == BD_ADDR_TYPE_ACL){
618             num_packets_sent_classic += connection->num_packets_sent;
619         }
620     }
621     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
622     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
623     int free_slots_le = 0;
624 
625     if (free_slots_classic < 0){
626         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
627         return 0;
628     }
629 
630     if (hci_stack->le_acl_packets_total_num){
631         // if we have LE slots, they are used
632         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
633         if (free_slots_le < 0){
634             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
635             return 0;
636         }
637     } else {
638         // otherwise, classic slots are used for LE, too
639         free_slots_classic -= num_packets_sent_le;
640         if (free_slots_classic < 0){
641             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
642             return 0;
643         }
644     }
645 
646     switch (address_type){
647         case BD_ADDR_TYPE_UNKNOWN:
648             log_error("hci_number_free_acl_slots: unknown address type");
649             return 0;
650 
651         case BD_ADDR_TYPE_ACL:
652             return (uint16_t) free_slots_classic;
653 
654         default:
655            if (hci_stack->le_acl_packets_total_num > 0){
656                return (uint16_t) free_slots_le;
657            }
658            return (uint16_t) free_slots_classic;
659     }
660 }
661 
662 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
663     // get connection type
664     hci_connection_t * connection = hci_connection_for_handle(con_handle);
665     if (!connection){
666         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
667         return 0;
668     }
669     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
670 }
671 
672 #ifdef ENABLE_CLASSIC
673 static int hci_number_free_sco_slots(void){
674     unsigned int num_sco_packets_sent  = 0;
675     btstack_linked_item_t *it;
676     if (hci_stack->synchronous_flow_control_enabled){
677         // explicit flow control
678         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
679             hci_connection_t * connection = (hci_connection_t *) it;
680             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
681             num_sco_packets_sent += connection->num_packets_sent;
682         }
683         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
684             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
685             return 0;
686         }
687         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
688     } else {
689         // implicit flow control -- TODO
690         int num_ready = 0;
691         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
692             hci_connection_t * connection = (hci_connection_t *) it;
693             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
694             if (connection->sco_tx_ready == 0) continue;
695             num_ready++;
696         }
697         return num_ready;
698     }
699 }
700 #endif
701 
702 // only used to send HCI Host Number Completed Packets
703 static int hci_can_send_comand_packet_transport(void){
704     if (hci_stack->hci_packet_buffer_reserved) return 0;
705 
706     // check for async hci transport implementations
707     if (hci_stack->hci_transport->can_send_packet_now){
708         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
709             return 0;
710         }
711     }
712     return 1;
713 }
714 
715 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
716 bool hci_can_send_command_packet_now(void){
717     if (hci_can_send_comand_packet_transport() == 0) return false;
718     return hci_stack->num_cmd_packets > 0u;
719 }
720 
721 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
722     // check for async hci transport implementations
723     if (!hci_stack->hci_transport->can_send_packet_now) return true;
724     return hci_stack->hci_transport->can_send_packet_now(packet_type);
725 }
726 
727 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
728     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
729     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
730 }
731 
732 bool hci_can_send_acl_le_packet_now(void){
733     if (hci_stack->hci_packet_buffer_reserved) return false;
734     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
735 }
736 
737 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
738     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
739     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
740 }
741 
742 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
743     if (hci_stack->hci_packet_buffer_reserved) return false;
744     return hci_can_send_prepared_acl_packet_now(con_handle);
745 }
746 
747 #ifdef ENABLE_CLASSIC
748 bool hci_can_send_acl_classic_packet_now(void){
749     if (hci_stack->hci_packet_buffer_reserved) return false;
750     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
751 }
752 
753 bool hci_can_send_prepared_sco_packet_now(void){
754     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
755     if (hci_have_usb_transport()){
756         return hci_stack->sco_can_send_now;
757     } else {
758         return hci_number_free_sco_slots() > 0;
759     }
760 }
761 
762 bool hci_can_send_sco_packet_now(void){
763     if (hci_stack->hci_packet_buffer_reserved) return false;
764     return hci_can_send_prepared_sco_packet_now();
765 }
766 
767 void hci_request_sco_can_send_now_event(void){
768     hci_stack->sco_waiting_for_can_send_now = 1;
769     hci_notify_if_sco_can_send_now();
770 }
771 #endif
772 
773 // used for internal checks in l2cap.c
774 bool hci_is_packet_buffer_reserved(void){
775     return hci_stack->hci_packet_buffer_reserved;
776 }
777 
778 // reserves outgoing packet buffer.
779 // @return 1 if successful
780 bool hci_reserve_packet_buffer(void){
781     if (hci_stack->hci_packet_buffer_reserved) {
782         log_error("hci_reserve_packet_buffer called but buffer already reserved");
783         return false;
784     }
785     hci_stack->hci_packet_buffer_reserved = true;
786     return true;
787 }
788 
789 void hci_release_packet_buffer(void){
790     hci_stack->hci_packet_buffer_reserved = false;
791 }
792 
793 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
794 static int hci_transport_synchronous(void){
795     return hci_stack->hci_transport->can_send_packet_now == NULL;
796 }
797 
798 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
799 
800     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
801 
802     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
803     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
804     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
805         max_acl_data_packet_length = hci_stack->le_data_packets_length;
806     }
807 
808 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
809     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
810         max_acl_data_packet_length = connection->le_max_tx_octets;
811     }
812 #endif
813 
814     log_debug("hci_send_acl_packet_fragments entered");
815 
816     uint8_t status = ERROR_CODE_SUCCESS;
817     // multiple packets could be send on a synchronous HCI transport
818     while (true){
819 
820         log_debug("hci_send_acl_packet_fragments loop entered");
821 
822         // get current data
823         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
824         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
825         bool more_fragments = false;
826 
827         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
828         if (current_acl_data_packet_length > max_acl_data_packet_length){
829             more_fragments = true;
830             current_acl_data_packet_length = max_acl_data_packet_length;
831         }
832 
833         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
834         if (acl_header_pos > 0u){
835             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
836             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
837             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
838         }
839 
840         // update header len
841         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
842 
843         // count packet
844         connection->num_packets_sent++;
845         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
846 
847         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
848         if (more_fragments){
849             // update start of next fragment to send
850             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
851         } else {
852             // done
853             hci_stack->acl_fragmentation_pos = 0;
854             hci_stack->acl_fragmentation_total_size = 0;
855         }
856 
857         // send packet
858         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
859         const int size = current_acl_data_packet_length + 4;
860         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
861         hci_stack->acl_fragmentation_tx_active = 1;
862         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
863         if (err != 0){
864             // no error from HCI Transport expected
865             status = ERROR_CODE_HARDWARE_FAILURE;
866         }
867 
868         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
869 
870         // done yet?
871         if (!more_fragments) break;
872 
873         // can send more?
874         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
875     }
876 
877     log_debug("hci_send_acl_packet_fragments loop over");
878 
879     // release buffer now for synchronous transport
880     if (hci_transport_synchronous()){
881         hci_stack->acl_fragmentation_tx_active = 0;
882         hci_release_packet_buffer();
883         hci_emit_transport_packet_sent();
884     }
885 
886     return status;
887 }
888 
889 // pre: caller has reserved the packet buffer
890 uint8_t hci_send_acl_packet_buffer(int size){
891     btstack_assert(hci_stack->hci_packet_buffer_reserved);
892 
893     uint8_t * packet = hci_stack->hci_packet_buffer;
894     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
895 
896     // check for free places on Bluetooth module
897     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
898         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
899         hci_release_packet_buffer();
900         hci_emit_transport_packet_sent();
901         return BTSTACK_ACL_BUFFERS_FULL;
902     }
903 
904     hci_connection_t *connection = hci_connection_for_handle( con_handle);
905     if (!connection) {
906         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
907         hci_release_packet_buffer();
908         hci_emit_transport_packet_sent();
909         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
910     }
911 
912 #ifdef ENABLE_CLASSIC
913     hci_connection_timestamp(connection);
914 #endif
915 
916     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
917 
918     // setup data
919     hci_stack->acl_fragmentation_total_size = size;
920     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
921 
922     return hci_send_acl_packet_fragments(connection);
923 }
924 
925 #ifdef ENABLE_CLASSIC
926 // pre: caller has reserved the packet buffer
927 uint8_t hci_send_sco_packet_buffer(int size){
928     btstack_assert(hci_stack->hci_packet_buffer_reserved);
929 
930     uint8_t * packet = hci_stack->hci_packet_buffer;
931 
932     // skip checks in loopback mode
933     if (!hci_stack->loopback_mode){
934         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
935 
936         // check for free places on Bluetooth module
937         if (!hci_can_send_prepared_sco_packet_now()) {
938             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
939             hci_release_packet_buffer();
940             hci_emit_transport_packet_sent();
941             return BTSTACK_ACL_BUFFERS_FULL;
942         }
943 
944         // track send packet in connection struct
945         hci_connection_t *connection = hci_connection_for_handle( con_handle);
946         if (!connection) {
947             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
948             hci_release_packet_buffer();
949             hci_emit_transport_packet_sent();
950             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
951         }
952 
953         if (hci_have_usb_transport()){
954             // token used
955             hci_stack->sco_can_send_now = false;
956         } else {
957             if (hci_stack->synchronous_flow_control_enabled){
958                 connection->num_packets_sent++;
959             } else {
960                 connection->sco_tx_ready--;
961             }
962         }
963     }
964 
965     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
966 
967 #ifdef HAVE_SCO_TRANSPORT
968     hci_stack->sco_transport->send_packet(packet, size);
969     hci_release_packet_buffer();
970     hci_emit_transport_packet_sent();
971 
972     return 0;
973 #else
974     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
975     if (hci_transport_synchronous()){
976         hci_release_packet_buffer();
977         hci_emit_transport_packet_sent();
978     }
979 
980     if (err != 0){
981         return ERROR_CODE_HARDWARE_FAILURE;
982     }
983     return ERROR_CODE_SUCCESS;
984 #endif
985 }
986 #endif
987 
988 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
989 static uint8_t hci_send_iso_packet_fragments(void){
990 
991     uint16_t max_iso_data_packet_length = hci_stack->le_iso_packets_length;
992     uint8_t status = ERROR_CODE_SUCCESS;
993     // multiple packets could be send on a synchronous HCI transport
994     while (true){
995 
996         // get current data
997         const uint16_t iso_header_pos = hci_stack->iso_fragmentation_pos - 4u;
998         int current_iso_data_packet_length = hci_stack->iso_fragmentation_total_size - hci_stack->iso_fragmentation_pos;
999         bool more_fragments = false;
1000 
1001         // if ISO packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
1002         if (current_iso_data_packet_length > max_iso_data_packet_length){
1003             more_fragments = true;
1004             current_iso_data_packet_length = max_iso_data_packet_length;
1005         }
1006 
1007         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
1008         uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1009         uint8_t pb_flags;
1010         if (iso_header_pos == 0u){
1011             // first fragment, keep TS field
1012             pb_flags = more_fragments ? 0x00 : 0x02;
1013             handle_and_flags = (handle_and_flags & 0x4fffu) | (pb_flags << 12u);
1014         } else {
1015             // later fragment, drop TS field
1016             pb_flags = more_fragments ? 0x01 : 0x03;
1017             handle_and_flags = (handle_and_flags & 0x0fffu) | (pb_flags << 12u);
1018         }
1019         little_endian_store_16(hci_stack->hci_packet_buffer, iso_header_pos, handle_and_flags);
1020 
1021         // update header len
1022         little_endian_store_16(hci_stack->hci_packet_buffer, iso_header_pos + 2u, current_iso_data_packet_length);
1023 
1024         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
1025         if (more_fragments){
1026             // update start of next fragment to send
1027             hci_stack->iso_fragmentation_pos += current_iso_data_packet_length;
1028         } else {
1029             // done
1030             hci_stack->iso_fragmentation_pos = 0;
1031             hci_stack->iso_fragmentation_total_size = 0;
1032         }
1033 
1034         // send packet
1035         uint8_t * packet = &hci_stack->hci_packet_buffer[iso_header_pos];
1036         const int size = current_iso_data_packet_length + 4;
1037         hci_dump_packet(HCI_ISO_DATA_PACKET, 0, packet, size);
1038         hci_stack->iso_fragmentation_tx_active = true;
1039         int err = hci_stack->hci_transport->send_packet(HCI_ISO_DATA_PACKET, packet, size);
1040         if (err != 0){
1041             // no error from HCI Transport expected
1042             status = ERROR_CODE_HARDWARE_FAILURE;
1043         }
1044 
1045         // done yet?
1046         if (!more_fragments) break;
1047 
1048         // can send more?
1049         if (!hci_transport_can_send_prepared_packet_now(HCI_ISO_DATA_PACKET)) return false;
1050     }
1051 
1052     // release buffer now for synchronous transport
1053     if (hci_transport_synchronous()){
1054         hci_stack->iso_fragmentation_tx_active = false;
1055         hci_release_packet_buffer();
1056         hci_emit_transport_packet_sent();
1057     }
1058 
1059     return status;
1060 }
1061 
1062 uint8_t hci_send_iso_packet_buffer(uint16_t size){
1063     btstack_assert(hci_stack->hci_packet_buffer_reserved);
1064 
1065     // setup data
1066     hci_stack->iso_fragmentation_total_size = size;
1067     hci_stack->iso_fragmentation_pos = 4;   // start of L2CAP packet
1068 
1069     // TODO: check for space on controller
1070     // TODO: track outgoing packet sent
1071 
1072     return hci_send_iso_packet_fragments();
1073 }
1074 #endif
1075 
1076 static void acl_handler(uint8_t *packet, uint16_t size){
1077 
1078     // get info
1079     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
1080     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
1081     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
1082     uint16_t acl_length         = READ_ACL_LENGTH(packet);
1083 
1084     // ignore non-registered handle
1085     if (!conn){
1086         log_error("acl_handler called with non-registered handle %u!" , con_handle);
1087         return;
1088     }
1089 
1090     // assert packet is complete
1091     if ((acl_length + 4u) != size){
1092         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
1093         return;
1094     }
1095 
1096 #ifdef ENABLE_CLASSIC
1097     // update idle timestamp
1098     hci_connection_timestamp(conn);
1099 #endif
1100 
1101 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1102     hci_stack->host_completed_packets = 1;
1103     conn->num_packets_completed++;
1104 #endif
1105 
1106     // handle different packet types
1107     switch (acl_flags & 0x03u) {
1108 
1109         case 0x01: // continuation fragment
1110 
1111             // sanity checks
1112             if (conn->acl_recombination_pos == 0u) {
1113                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
1114                 return;
1115             }
1116             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
1117                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
1118                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1119                 conn->acl_recombination_pos = 0;
1120                 return;
1121             }
1122 
1123             // append fragment payload (header already stored)
1124             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
1125                          &packet[4], acl_length);
1126             conn->acl_recombination_pos += acl_length;
1127 
1128             // forward complete L2CAP packet if complete.
1129             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
1130                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
1131                 // reset recombination buffer
1132                 conn->acl_recombination_length = 0;
1133                 conn->acl_recombination_pos = 0;
1134             }
1135             break;
1136 
1137         case 0x02: { // first fragment
1138 
1139             // sanity check
1140             if (conn->acl_recombination_pos) {
1141                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
1142                 conn->acl_recombination_pos = 0;
1143             }
1144 
1145             // peek into L2CAP packet!
1146             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
1147 
1148             // compare fragment size to L2CAP packet size
1149             if (acl_length >= (l2cap_length + 4u)){
1150                 // forward fragment as L2CAP packet
1151                 hci_emit_acl_packet(packet, acl_length + 4u);
1152             } else {
1153 
1154                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1155                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1156                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1157                     return;
1158                 }
1159 
1160                 // store first fragment and tweak acl length for complete package
1161                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1162                              packet, acl_length + 4u);
1163                 conn->acl_recombination_pos    = acl_length + 4u;
1164                 conn->acl_recombination_length = l2cap_length;
1165                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1166             }
1167             break;
1168 
1169         }
1170         default:
1171             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1172             return;
1173     }
1174 
1175     // execute main loop
1176     hci_run();
1177 }
1178 
1179 static void hci_connection_stop_timer(hci_connection_t * conn){
1180     btstack_run_loop_remove_timer(&conn->timeout);
1181 #ifdef ENABLE_CLASSIC
1182     btstack_run_loop_remove_timer(&conn->timeout_sco);
1183 #endif
1184 }
1185 
1186 static void hci_shutdown_connection(hci_connection_t *conn){
1187     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1188 
1189 #ifdef ENABLE_CLASSIC
1190 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1191     bd_addr_type_t addr_type = conn->address_type;
1192 #endif
1193 #ifdef HAVE_SCO_TRANSPORT
1194     hci_con_handle_t con_handle = conn->con_handle;
1195 #endif
1196 #endif
1197 
1198     hci_connection_stop_timer(conn);
1199 
1200     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1201     btstack_memory_hci_connection_free( conn );
1202 
1203     // now it's gone
1204     hci_emit_nr_connections_changed();
1205 
1206 #ifdef ENABLE_CLASSIC
1207 #ifdef ENABLE_SCO_OVER_HCI
1208     // update SCO
1209     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1210         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1211     }
1212 #endif
1213 #ifdef HAVE_SCO_TRANSPORT
1214     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1215         hci_stack->sco_transport->close(con_handle);
1216     }
1217 #endif
1218 #endif
1219 }
1220 
1221 #ifdef ENABLE_CLASSIC
1222 
1223 static const uint16_t packet_type_sizes[] = {
1224     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1225     HCI_ACL_DH1_SIZE, 0, 0, 0,
1226     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1227     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1228 };
1229 static const uint8_t  packet_type_feature_requirement_bit[] = {
1230      0, // 3 slot packets
1231      1, // 5 slot packets
1232     25, // EDR 2 mpbs
1233     26, // EDR 3 mbps
1234     39, // 3 slot EDR packts
1235     40, // 5 slot EDR packet
1236 };
1237 static const uint16_t packet_type_feature_packet_mask[] = {
1238     0x0f00, // 3 slot packets
1239     0xf000, // 5 slot packets
1240     0x1102, // EDR 2 mpbs
1241     0x2204, // EDR 3 mbps
1242     0x0300, // 3 slot EDR packts
1243     0x3000, // 5 slot EDR packet
1244 };
1245 
1246 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1247     // enable packet types based on size
1248     uint16_t packet_types = 0;
1249     unsigned int i;
1250     for (i=0;i<16;i++){
1251         if (packet_type_sizes[i] == 0) continue;
1252         if (packet_type_sizes[i] <= buffer_size){
1253             packet_types |= 1 << i;
1254         }
1255     }
1256     // disable packet types due to missing local supported features
1257     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1258         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1259         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1260         if (feature_set) continue;
1261         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1262         packet_types &= ~packet_type_feature_packet_mask[i];
1263     }
1264     // flip bits for "may not be used"
1265     packet_types ^= 0x3306;
1266     return packet_types;
1267 }
1268 
1269 uint16_t hci_usable_acl_packet_types(void){
1270     return hci_stack->packet_types;
1271 }
1272 #endif
1273 
1274 uint8_t* hci_get_outgoing_packet_buffer(void){
1275     // hci packet buffer is >= acl data packet length
1276     return hci_stack->hci_packet_buffer;
1277 }
1278 
1279 uint16_t hci_max_acl_data_packet_length(void){
1280     return hci_stack->acl_data_packet_length;
1281 }
1282 
1283 #ifdef ENABLE_CLASSIC
1284 bool hci_extended_sco_link_supported(void){
1285     // No. 31, byte 3, bit 7
1286     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1287 }
1288 #endif
1289 
1290 bool hci_non_flushable_packet_boundary_flag_supported(void){
1291     // No. 54, byte 6, bit 6
1292     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1293 }
1294 
1295 #ifdef ENABLE_CLASSIC
1296 static int gap_ssp_supported(void){
1297     // No. 51, byte 6, bit 3
1298     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1299 }
1300 #endif
1301 
1302 static int hci_classic_supported(void){
1303 #ifdef ENABLE_CLASSIC
1304     // No. 37, byte 4, bit 5, = No BR/EDR Support
1305     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1306 #else
1307     return 0;
1308 #endif
1309 }
1310 
1311 static int hci_le_supported(void){
1312 #ifdef ENABLE_BLE
1313     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1314     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1315 #else
1316     return 0;
1317 #endif
1318 }
1319 
1320 static bool hci_command_supported(uint8_t command_index){
1321     return (hci_stack->local_supported_commands & (1LU << command_index)) != 0;
1322 }
1323 
1324 #ifdef ENABLE_BLE
1325 
1326 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
1327 static bool hci_extended_advertising_supported(void){
1328     return hci_command_supported(SUPPORTED_HCI_COMMAND_LE_SET_EXTENDED_ADVERTISING_ENABLE);
1329 }
1330 #endif
1331 
1332 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1333     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1334         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1335     } else {
1336         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1337     }
1338 }
1339 
1340 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1341     *addr_type = hci_stack->le_own_addr_type;
1342     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1343 }
1344 
1345 #ifdef ENABLE_LE_PERIPHERAL
1346 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1347     *addr_type = hci_stack->le_advertisements_own_addr_type;
1348     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1349 };
1350 #endif
1351 
1352 #ifdef ENABLE_LE_CENTRAL
1353 
1354 /**
1355  * @brief Get own addr type and address used for LE connections (Central)
1356  */
1357 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1358     *addr_type = hci_stack->le_connection_own_addr_type;
1359     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1360 }
1361 
1362 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1363 
1364     uint16_t offset = 3;
1365     uint8_t num_reports = packet[offset];
1366     offset += 1;
1367 
1368     uint16_t i;
1369     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1370     for (i=0; (i<num_reports) && (offset < size);i++){
1371         // sanity checks on data_length:
1372         uint8_t data_length = packet[offset + 8];
1373         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1374         if ((offset + 9u + data_length + 1u) > size)    return;
1375         // setup event
1376         uint8_t event_size = 10u + data_length;
1377         uint16_t pos = 0;
1378         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1379         event[pos++] = event_size;
1380         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1381         offset += 8;
1382         pos += 8;
1383         event[pos++] = packet[offset + 1 + data_length]; // rssi
1384         event[pos++] = data_length;
1385         offset++;
1386         (void)memcpy(&event[pos], &packet[offset], data_length);
1387         pos +=    data_length;
1388         offset += data_length + 1u; // rssi
1389         hci_emit_event(event, pos, 1);
1390     }
1391 }
1392 
1393 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
1394 void le_handle_extended_advertisement_report(uint8_t *packet, uint16_t size) {
1395     uint16_t offset = 3;
1396     uint8_t num_reports = packet[offset++];
1397     uint8_t event[2 + 255]; // use upper bound to avoid var size automatic var
1398     uint8_t i;
1399     for (i=0; (i<num_reports) && (offset < size);i++){
1400         // sanity checks on data_length:
1401         uint16_t data_length = packet[offset + 23];
1402         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1403         if ((offset + 24u + data_length) > size)    return;
1404         uint16_t event_type = little_endian_read_16(packet, offset);
1405         offset += 2;
1406         if ((event_type & 0x10) != 0) {
1407            // setup legacy event
1408             uint8_t legacy_event_type;
1409             switch (event_type){
1410                 case 0b0010011:
1411                     // ADV_IND
1412                     legacy_event_type = 0;
1413                     break;
1414                 case 0b0010101:
1415                     // ADV_DIRECT_IND
1416                     legacy_event_type = 1;
1417                     break;
1418                 case 0b0010010:
1419                     // ADV_SCAN_IND
1420                     legacy_event_type = 2;
1421                     break;
1422                 case 0b0010000:
1423                     // ADV_NONCONN_IND
1424                     legacy_event_type = 3;
1425                     break;
1426                 case 0b0011011:
1427                 case 0b0011010:
1428                     // SCAN_RSP
1429                     legacy_event_type = 4;
1430                     break;
1431                 default:
1432                     legacy_event_type = 0;
1433                     break;
1434             }
1435             uint16_t pos = 0;
1436             event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1437             event[pos++] = 10u + data_length;
1438             event[pos++] = legacy_event_type;
1439             // copy address type + address
1440             (void) memcpy(&event[pos], &packet[offset], 1 + 6);
1441             offset += 7;
1442             pos += 7;
1443             // skip primary_phy, secondary_phy, advertising_sid, tx_power
1444             offset += 4;
1445             // copy rssi
1446             event[pos++] = packet[offset++];
1447             // skip periodic advertising interval and direct address
1448             offset += 9;
1449             // copy data len + data;
1450             (void) memcpy(&event[pos], &packet[offset], 1 + data_length);
1451             pos    += 1 +data_length;
1452             offset += 1+ data_length;
1453             hci_emit_event(event, pos, 1);
1454         } else {
1455             event[0] = GAP_EVENT_EXTENDED_ADVERTISING_REPORT;
1456             uint8_t report_len = 24 + data_length;
1457             event[1] = report_len;
1458             little_endian_store_16(event, 2, event_type);
1459             memcpy(&event[4], &packet[offset], report_len);
1460             offset += report_len;
1461             hci_emit_event(event, 2 + report_len, 1);
1462         }
1463     }
1464 }
1465 #endif
1466 
1467 #endif
1468 #endif
1469 
1470 #ifdef ENABLE_BLE
1471 #ifdef ENABLE_LE_PERIPHERAL
1472 static void hci_update_advertisements_enabled_for_current_roles(void){
1473     if ((hci_stack->le_advertisements_state & LE_ADVERTISEMENT_STATE_ENABLED) != 0){
1474         // get number of active le slave connections
1475         int num_slave_connections = 0;
1476         btstack_linked_list_iterator_t it;
1477         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1478         while (btstack_linked_list_iterator_has_next(&it)){
1479             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1480             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1481             if (con->state != OPEN) continue;
1482             if (con->role  != HCI_ROLE_SLAVE) continue;
1483             if (!hci_is_le_connection(con)) continue;
1484             num_slave_connections++;
1485         }
1486         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1487         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1488     } else {
1489         hci_stack->le_advertisements_enabled_for_current_roles = false;
1490     }
1491 }
1492 #endif
1493 #endif
1494 
1495 #ifdef ENABLE_CLASSIC
1496 static void gap_run_set_local_name(void){
1497     hci_reserve_packet_buffer();
1498     uint8_t * packet = hci_stack->hci_packet_buffer;
1499     // construct HCI Command and send
1500     uint16_t opcode = hci_write_local_name.opcode;
1501     hci_stack->last_cmd_opcode = opcode;
1502     packet[0] = opcode & 0xff;
1503     packet[1] = opcode >> 8;
1504     packet[2] = DEVICE_NAME_LEN;
1505     memset(&packet[3], 0, DEVICE_NAME_LEN);
1506     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1507     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1508     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1509     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1510     // expand '00:00:00:00:00:00' in name with bd_addr
1511     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1512     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1513 }
1514 
1515 static void gap_run_set_eir_data(void){
1516     hci_reserve_packet_buffer();
1517     uint8_t * packet = hci_stack->hci_packet_buffer;
1518     // construct HCI Command in-place and send
1519     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1520     hci_stack->last_cmd_opcode = opcode;
1521     uint16_t offset = 0;
1522     packet[offset++] = opcode & 0xff;
1523     packet[offset++] = opcode >> 8;
1524     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1525     packet[offset++] = 0;  // FEC not required
1526     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1527     if (hci_stack->eir_data){
1528         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1529         ad_context_t context;
1530         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1531             uint8_t data_type   = ad_iterator_get_data_type(&context);
1532             uint8_t size        = ad_iterator_get_data_len(&context);
1533             const uint8_t *data = ad_iterator_get_data(&context);
1534             // copy item
1535             packet[offset++] = size + 1;
1536             packet[offset++] = data_type;
1537             memcpy(&packet[offset], data, size);
1538             // update name item
1539             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1540                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1541             }
1542             offset += size;
1543         }
1544     } else {
1545         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1546         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1547         packet[offset++] = bytes_to_copy + 1;
1548         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1549         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1550         // expand '00:00:00:00:00:00' in name with bd_addr
1551         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1552     }
1553     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1554 }
1555 
1556 static void hci_run_gap_tasks_classic(void){
1557     if ((hci_stack->gap_tasks_classic & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1558         hci_stack->gap_tasks_classic &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1559         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1560         return;
1561     }
1562     if ((hci_stack->gap_tasks_classic & GAP_TASK_SET_LOCAL_NAME) != 0) {
1563         hci_stack->gap_tasks_classic &= ~GAP_TASK_SET_LOCAL_NAME;
1564         gap_run_set_local_name();
1565         return;
1566     }
1567     if ((hci_stack->gap_tasks_classic & GAP_TASK_SET_EIR_DATA) != 0) {
1568         hci_stack->gap_tasks_classic &= ~GAP_TASK_SET_EIR_DATA;
1569         gap_run_set_eir_data();
1570         return;
1571     }
1572     if ((hci_stack->gap_tasks_classic & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1573         hci_stack->gap_tasks_classic &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1574         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1575         return;
1576     }
1577     // write page scan activity
1578     if ((hci_stack->gap_tasks_classic & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1579         hci_stack->gap_tasks_classic &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1580         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1581         return;
1582     }
1583     // write page scan type
1584     if ((hci_stack->gap_tasks_classic & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1585         hci_stack->gap_tasks_classic &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1586         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1587         return;
1588     }
1589     // write page timeout
1590     if ((hci_stack->gap_tasks_classic & GAP_TASK_WRITE_PAGE_TIMEOUT) != 0) {
1591         hci_stack->gap_tasks_classic &= ~GAP_TASK_WRITE_PAGE_TIMEOUT;
1592         hci_send_cmd(&hci_write_page_timeout, hci_stack->page_timeout);
1593         return;
1594     }
1595     // send scan enable
1596     if ((hci_stack->gap_tasks_classic & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1597         hci_stack->gap_tasks_classic &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1598         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1599         return;
1600     }
1601     // send write scan activity
1602     if ((hci_stack->gap_tasks_classic & GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY) != 0) {
1603         hci_stack->gap_tasks_classic &= ~GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
1604         hci_send_cmd(&hci_write_inquiry_scan_activity, hci_stack->inquiry_scan_interval, hci_stack->inquiry_scan_window);
1605         return;
1606     }
1607 }
1608 #endif
1609 
1610 #ifndef HAVE_HOST_CONTROLLER_API
1611 
1612 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1613     if (!hci_stack->config) return 0;
1614     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1615     // Limit baud rate for Broadcom chipsets to 3 mbps
1616     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1617         baud_rate = 3000000;
1618     }
1619     return baud_rate;
1620 }
1621 
1622 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1623     UNUSED(ds);
1624 
1625     switch (hci_stack->substate){
1626         case HCI_INIT_W4_SEND_RESET:
1627             log_info("Resend HCI Reset");
1628             hci_stack->substate = HCI_INIT_SEND_RESET;
1629             hci_stack->num_cmd_packets = 1;
1630             hci_run();
1631             break;
1632         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1633             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1634             if (hci_stack->hci_transport->reset_link){
1635                 hci_stack->hci_transport->reset_link();
1636             }
1637 
1638             /* fall through */
1639 
1640         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1641             log_info("Resend HCI Reset - CSR Warm Boot");
1642             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1643             hci_stack->num_cmd_packets = 1;
1644             hci_run();
1645             break;
1646         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1647             if (hci_stack->hci_transport->set_baudrate){
1648                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1649                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1650                 hci_stack->hci_transport->set_baudrate(baud_rate);
1651             }
1652             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1653             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1654                 if (hci_stack->hci_transport->reset_link){
1655                     log_info("Link Reset");
1656                     hci_stack->hci_transport->reset_link();
1657                 }
1658                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1659                 hci_run();
1660             }
1661             break;
1662         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1663             // otherwise continue
1664             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1665             hci_send_cmd(&hci_read_local_supported_commands);
1666             break;
1667         default:
1668             break;
1669     }
1670 }
1671 #endif
1672 
1673 static void hci_initializing_next_state(void){
1674     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1675 }
1676 
1677 static void hci_init_done(void){
1678     // done. tell the app
1679     log_info("hci_init_done -> HCI_STATE_WORKING");
1680     hci_stack->state = HCI_STATE_WORKING;
1681     hci_emit_state();
1682 }
1683 
1684 // assumption: hci_can_send_command_packet_now() == true
1685 static void hci_initializing_run(void){
1686     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1687 
1688     if (!hci_can_send_command_packet_now()) return;
1689 
1690 #ifndef HAVE_HOST_CONTROLLER_API
1691     bool need_baud_change = hci_stack->config
1692             && hci_stack->chipset
1693             && hci_stack->chipset->set_baudrate_command
1694             && hci_stack->hci_transport->set_baudrate
1695             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1696 #endif
1697 
1698     switch (hci_stack->substate){
1699         case HCI_INIT_SEND_RESET:
1700             hci_state_reset();
1701 
1702 #ifndef HAVE_HOST_CONTROLLER_API
1703             // prepare reset if command complete not received in 100ms
1704             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1705             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1706             btstack_run_loop_add_timer(&hci_stack->timeout);
1707 #endif
1708             // send command
1709             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1710             hci_send_cmd(&hci_reset);
1711             break;
1712         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1713             hci_send_cmd(&hci_read_local_version_information);
1714             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1715             break;
1716 
1717 #ifndef HAVE_HOST_CONTROLLER_API
1718         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1719             hci_state_reset();
1720             // prepare reset if command complete not received in 100ms
1721             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1722             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1723             btstack_run_loop_add_timer(&hci_stack->timeout);
1724             // send command
1725             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1726             hci_send_cmd(&hci_reset);
1727             break;
1728         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1729             hci_state_reset();
1730             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1731             hci_send_cmd(&hci_reset);
1732             break;
1733         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1734             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1735             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1736             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1737             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1738             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1739             break;
1740         }
1741         case HCI_INIT_SET_BD_ADDR:
1742             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1743             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1744             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1745             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1746             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1747             break;
1748         case HCI_INIT_SEND_READ_LOCAL_NAME:
1749 #ifdef ENABLE_CLASSIC
1750             hci_send_cmd(&hci_read_local_name);
1751             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1752             break;
1753 #endif
1754             /* fall through */
1755 
1756         case HCI_INIT_SEND_BAUD_CHANGE:
1757             if (need_baud_change) {
1758                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1759                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1760                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1761                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1762                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1763                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1764                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1765                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1766                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1767                     btstack_run_loop_add_timer(&hci_stack->timeout);
1768                }
1769                break;
1770             }
1771 
1772             /* fall through */
1773 
1774         case HCI_INIT_CUSTOM_INIT:
1775             // Custom initialization
1776             if (hci_stack->chipset && hci_stack->chipset->next_command){
1777                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1778                 bool send_cmd = false;
1779                 switch (hci_stack->chipset_result){
1780                     case BTSTACK_CHIPSET_VALID_COMMAND:
1781                         send_cmd = true;
1782                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1783                         break;
1784                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1785                         send_cmd = true;
1786                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1787                         log_info("CSR Warm Boot");
1788                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1789                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1790                         btstack_run_loop_add_timer(&hci_stack->timeout);
1791                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1792                             && hci_stack->config
1793                             && hci_stack->chipset
1794                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1795                             && hci_stack->hci_transport->set_baudrate
1796                             && hci_transport_uart_get_main_baud_rate()){
1797                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1798                         } else {
1799                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1800                         }
1801                         break;
1802                     default:
1803                         break;
1804                 }
1805 
1806                 if (send_cmd){
1807                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1808                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1809                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1810                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1811                     break;
1812                 }
1813                 log_info("Init script done");
1814 
1815                 // Init script download on Broadcom chipsets causes:
1816                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1817                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1818                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1819 
1820                     // - baud rate to reset, restore UART baud rate if needed
1821                     if (need_baud_change) {
1822                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1823                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1824                         hci_stack->hci_transport->set_baudrate(baud_rate);
1825                     }
1826 
1827                     uint16_t bcm_delay_ms = 300;
1828                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1829                     //   -> Work around: wait here.
1830                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1831                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1832                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1833                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1834                     btstack_run_loop_add_timer(&hci_stack->timeout);
1835                     break;
1836                 }
1837             }
1838 #endif
1839             /* fall through */
1840 
1841         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1842             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1843             hci_send_cmd(&hci_read_local_supported_commands);
1844             break;
1845         case HCI_INIT_READ_BD_ADDR:
1846             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1847             hci_send_cmd(&hci_read_bd_addr);
1848             break;
1849         case HCI_INIT_READ_BUFFER_SIZE:
1850             // only read buffer size if supported
1851             if (hci_command_supported(SUPPORTED_HCI_COMMAND_READ_BUFFER_SIZE)){
1852                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1853                 hci_send_cmd(&hci_read_buffer_size);
1854                 break;
1855             }
1856 
1857             /* fall through */
1858 
1859         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1860             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1861             hci_send_cmd(&hci_read_local_supported_features);
1862             break;
1863 
1864 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1865         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1866             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1867             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1868             break;
1869         case HCI_INIT_HOST_BUFFER_SIZE:
1870             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1871             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1872                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1873             break;
1874 #endif
1875 
1876         case HCI_INIT_SET_EVENT_MASK:
1877             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1878             if (hci_le_supported()){
1879                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1880             } else {
1881                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1882                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1883             }
1884             break;
1885 
1886         case HCI_INIT_SET_EVENT_MASK_2:
1887             if (hci_command_supported(SUPPORTED_HCI_COMMAND_SET_EVENT_MASK_PAGE_2)){
1888                 hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK_2;
1889                 // Encryption Change Event v2 - bit 25
1890                 hci_send_cmd(&hci_set_event_mask_2,0x02000000U, 0x0);
1891                 break;
1892             }
1893 
1894 #ifdef ENABLE_CLASSIC
1895             /* fall through */
1896 
1897         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1898             if (hci_classic_supported() && gap_ssp_supported()){
1899                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1900                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1901                 break;
1902             }
1903 
1904             /* fall through */
1905 
1906         case HCI_INIT_WRITE_INQUIRY_MODE:
1907             if (hci_classic_supported()){
1908                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1909                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1910                 break;
1911             }
1912 
1913             /* fall through */
1914 
1915         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1916             // skip write secure connections host support if not supported or disabled
1917             if (hci_classic_supported() && hci_stack->secure_connections_enable
1918             && hci_command_supported(SUPPORTED_HCI_COMMAND_WRITE_SECURE_CONNECTIONS_HOST)) {
1919                 hci_stack->secure_connections_active = true;
1920                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1921                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1922                 break;
1923             }
1924 
1925             /* fall through */
1926 
1927         case HCI_INIT_SET_MIN_ENCRYPTION_KEY_SIZE:
1928             // skip set min encryption key size
1929             if (hci_classic_supported() && hci_command_supported(SUPPORTED_HCI_COMMAND_SET_MIN_ENCRYPTION_KEY_SIZE)) {
1930                 hci_stack->substate = HCI_INIT_W4_SET_MIN_ENCRYPTION_KEY_SIZE;
1931                 hci_send_cmd(&hci_set_min_encryption_key_size, hci_stack->gap_required_encyrption_key_size);
1932                 break;
1933             }
1934 
1935 #ifdef ENABLE_SCO_OVER_HCI
1936             /* fall through */
1937 
1938         // only sent if ENABLE_SCO_OVER_HCI is defined
1939         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1940             // skip write synchronous flow control if not supported
1941             if (hci_classic_supported()
1942             && hci_command_supported(SUPPORTED_HCI_COMMAND_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE)) {
1943                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1944                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1945                 break;
1946             }
1947             /* fall through */
1948 
1949         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1950             // skip write default erroneous data reporting if not supported
1951             if (hci_classic_supported()
1952             && hci_command_supported(SUPPORTED_HCI_COMMAND_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING)) {
1953                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1954                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1955                 break;
1956             }
1957 #endif
1958 
1959 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1960             /* fall through */
1961 
1962         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1963         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1964             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1965                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1966 #ifdef ENABLE_SCO_OVER_HCI
1967                 log_info("BCM: Route SCO data via HCI transport");
1968                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1969 #endif
1970 #ifdef ENABLE_SCO_OVER_PCM
1971                 log_info("BCM: Route SCO data via PCM interface");
1972 #ifdef ENABLE_BCM_PCM_WBS
1973                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1974                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1975 #else
1976                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1977                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1978 #endif
1979 #endif
1980                 break;
1981             }
1982 #endif
1983 
1984 #ifdef ENABLE_SCO_OVER_PCM
1985             /* fall through */
1986 
1987         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1988             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1989                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1990                 log_info("BCM: Config PCM interface for I2S");
1991 #ifdef ENABLE_BCM_PCM_WBS
1992                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1993                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1994 #else
1995                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1996                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1997 #endif
1998                 break;
1999             }
2000 #endif
2001 #endif
2002 
2003 #ifdef ENABLE_BLE
2004             /* fall through */
2005 
2006         // LE INIT
2007         case HCI_INIT_LE_READ_BUFFER_SIZE:
2008             if (hci_le_supported()){
2009                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
2010                 if (hci_command_supported(SUPPORTED_HCI_COMMAND_LE_READ_BUFFER_SIZE_V2)){
2011                     hci_send_cmd(&hci_le_read_buffer_size_v2);
2012                 } else {
2013                     hci_send_cmd(&hci_le_read_buffer_size);
2014                 }
2015                 break;
2016             }
2017 
2018             /* fall through */
2019 
2020         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
2021             // skip write le host if not supported (e.g. on LE only EM9301)
2022             if (hci_le_supported()
2023             && hci_command_supported(SUPPORTED_HCI_COMMAND_WRITE_LE_HOST_SUPPORTED)) {
2024                 // LE Supported Host = 1, Simultaneous Host = 0
2025                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
2026                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
2027                 break;
2028             }
2029 
2030             /* fall through */
2031 
2032         case HCI_INIT_LE_SET_EVENT_MASK:
2033             if (hci_le_supported()){
2034                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
2035                 hci_send_cmd(&hci_le_set_event_mask, 0xfffffdff, 0x07); // all events from core v5.3 without LE Enhanced Connection Complete
2036                 break;
2037             }
2038 #endif
2039 
2040 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2041             /* fall through */
2042 
2043         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
2044             if (hci_le_supported()
2045             && hci_command_supported(SUPPORTED_HCI_COMMAND_LE_READ_MAXIMUM_DATA_LENGTH)) {
2046                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
2047                 hci_send_cmd(&hci_le_read_maximum_data_length);
2048                 break;
2049             }
2050 
2051             /* fall through */
2052 
2053         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
2054             if (hci_le_supported()
2055             && hci_command_supported(SUPPORTED_HCI_COMMAND_LE_WRITE_SUGGESTED_DEFAULT_DATA_LENGTH)) {
2056                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
2057                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
2058                 break;
2059             }
2060 #endif
2061 
2062 #ifdef ENABLE_LE_CENTRAL
2063             /* fall through */
2064 
2065         case HCI_INIT_READ_WHITE_LIST_SIZE:
2066             if (hci_le_supported()){
2067                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
2068                 hci_send_cmd(&hci_le_read_white_list_size);
2069                 break;
2070             }
2071 
2072 #endif
2073 
2074 #ifdef ENABLE_LE_PERIPHERAL
2075 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
2076             /* fall through */
2077 
2078         case HCI_INIT_LE_READ_MAX_ADV_DATA_LEN:
2079             if (hci_extended_advertising_supported()){
2080                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_ADV_DATA_LEN;
2081                 hci_send_cmd(&hci_le_read_maximum_advertising_data_length);
2082                 break;
2083             }
2084 #endif
2085 #endif
2086             /* fall through */
2087 
2088         case HCI_INIT_DONE:
2089             hci_stack->substate = HCI_INIT_DONE;
2090             // main init sequence complete
2091 #ifdef ENABLE_CLASSIC
2092             // check if initial Classic GAP Tasks are completed
2093             if (hci_classic_supported() && (hci_stack->gap_tasks_classic != 0)) {
2094                 hci_run_gap_tasks_classic();
2095                 break;
2096             }
2097 #endif
2098 #ifdef ENABLE_BLE
2099 #ifdef ENABLE_LE_CENTRAL
2100             // check if initial LE GAP Tasks are completed
2101             if (hci_le_supported() && hci_stack->le_scanning_param_update) {
2102                 hci_run_general_gap_le();
2103                 break;
2104             }
2105 #endif
2106 #endif
2107             hci_init_done();
2108             break;
2109 
2110         default:
2111             return;
2112     }
2113 }
2114 
2115 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
2116     bool command_completed = false;
2117     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
2118         uint16_t opcode = little_endian_read_16(packet,3);
2119         if (opcode == hci_stack->last_cmd_opcode){
2120             command_completed = true;
2121             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
2122         } else {
2123             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
2124         }
2125     }
2126 
2127     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
2128         uint8_t  status = packet[2];
2129         uint16_t opcode = little_endian_read_16(packet,4);
2130         if (opcode == hci_stack->last_cmd_opcode){
2131             if (status){
2132                 command_completed = true;
2133                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
2134             } else {
2135                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
2136             }
2137         } else {
2138             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
2139         }
2140     }
2141 #ifndef HAVE_HOST_CONTROLLER_API
2142     // Vendor == CSR
2143     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
2144         // TODO: track actual command
2145         command_completed = true;
2146     }
2147 
2148     // Vendor == Toshiba
2149     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
2150         // TODO: track actual command
2151         command_completed = true;
2152         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
2153         hci_stack->num_cmd_packets = 1;
2154     }
2155 #endif
2156 
2157     return command_completed;
2158 }
2159 
2160 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
2161 
2162     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
2163 
2164     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
2165 
2166 #ifndef HAVE_HOST_CONTROLLER_API
2167 
2168     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
2169     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
2170     //
2171     // HCI Reset
2172     // Timeout 100 ms
2173     // HCI Reset
2174     // Command Complete Reset
2175     // HCI Read Local Version Information
2176     // Command Complete Reset - but we expected Command Complete Read Local Version Information
2177     // hang...
2178     //
2179     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
2180     if (!command_completed
2181             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
2182             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
2183 
2184         uint16_t opcode = little_endian_read_16(packet,3);
2185         if (opcode == hci_reset.opcode){
2186             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
2187             return;
2188         }
2189     }
2190 
2191     // CSR & H5
2192     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
2193     if (!command_completed
2194             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
2195             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
2196 
2197         uint16_t opcode = little_endian_read_16(packet,3);
2198         if (opcode == hci_reset.opcode){
2199             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
2200             return;
2201         }
2202     }
2203 
2204     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
2205     // fix: Correct substate and behave as command below
2206     if (command_completed){
2207         switch (hci_stack->substate){
2208             case HCI_INIT_SEND_RESET:
2209                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
2210                 break;
2211             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
2212                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
2213                 break;
2214             default:
2215                 break;
2216         }
2217     }
2218 
2219 #endif
2220 
2221     if (!command_completed) return;
2222 
2223     bool need_baud_change = false;
2224     bool need_addr_change = false;
2225 
2226 #ifndef HAVE_HOST_CONTROLLER_API
2227     need_baud_change = hci_stack->config
2228                         && hci_stack->chipset
2229                         && hci_stack->chipset->set_baudrate_command
2230                         && hci_stack->hci_transport->set_baudrate
2231                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
2232 
2233     need_addr_change = hci_stack->custom_bd_addr_set
2234                         && hci_stack->chipset
2235                         && hci_stack->chipset->set_bd_addr_command;
2236 #endif
2237 
2238     switch(hci_stack->substate){
2239 
2240 #ifndef HAVE_HOST_CONTROLLER_API
2241         case HCI_INIT_SEND_RESET:
2242             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
2243             // fix: just correct substate and behave as command below
2244 
2245             /* fall through */
2246 #endif
2247 
2248         case HCI_INIT_W4_SEND_RESET:
2249             btstack_run_loop_remove_timer(&hci_stack->timeout);
2250             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
2251             return;
2252 
2253 #ifndef HAVE_HOST_CONTROLLER_API
2254         case HCI_INIT_W4_SEND_BAUD_CHANGE:
2255             // for STLC2500D, baud rate change already happened.
2256             // for others, baud rate gets changed now
2257             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
2258                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
2259                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
2260                 hci_stack->hci_transport->set_baudrate(baud_rate);
2261             }
2262             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
2263             return;
2264         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
2265             btstack_run_loop_remove_timer(&hci_stack->timeout);
2266             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
2267             return;
2268         case HCI_INIT_W4_CUSTOM_INIT:
2269             // repeat custom init
2270             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
2271             return;
2272 #endif
2273 
2274         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
2275             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
2276               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
2277                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
2278                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
2279                 return;
2280             }
2281             if (need_addr_change){
2282                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2283                 return;
2284             }
2285             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2286             return;
2287 #ifndef HAVE_HOST_CONTROLLER_API
2288         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
2289             if (need_baud_change){
2290                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
2291                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
2292                 hci_stack->hci_transport->set_baudrate(baud_rate);
2293             }
2294             if (need_addr_change){
2295                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2296                 return;
2297             }
2298             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2299             return;
2300         case HCI_INIT_W4_SET_BD_ADDR:
2301             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
2302             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
2303             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2304                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2305                 return;
2306             }
2307             // skipping st warm boot
2308             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2309             return;
2310         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2311             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2312             return;
2313 #endif
2314 
2315         case HCI_INIT_DONE:
2316             // set state if we came here by fall through
2317             hci_stack->substate = HCI_INIT_DONE;
2318             return;
2319 
2320         default:
2321             break;
2322     }
2323     hci_initializing_next_state();
2324 }
2325 
2326 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2327     // CC2564C might emit Connection Complete for rejected incoming SCO connection
2328     // To prevent accidentally free'ing the HCI connection for the ACL connection,
2329     // check if we have been aware of the HCI connection
2330     switch (conn->state){
2331         case SENT_CREATE_CONNECTION:
2332         case RECEIVED_CONNECTION_REQUEST:
2333             break;
2334         default:
2335             return;
2336     }
2337 
2338     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2339     bd_addr_t bd_address;
2340     (void)memcpy(&bd_address, conn->address, 6);
2341 
2342 #ifdef ENABLE_CLASSIC
2343     // cache needed data
2344     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2345 #endif
2346 
2347     // connection failed, remove entry
2348     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2349     btstack_memory_hci_connection_free( conn );
2350 
2351 #ifdef ENABLE_CLASSIC
2352     // notify client if dedicated bonding
2353     if (notify_dedicated_bonding_failed){
2354         log_info("hci notify_dedicated_bonding_failed");
2355         hci_emit_dedicated_bonding_result(bd_address, status);
2356     }
2357 
2358     // if authentication error, also delete link key
2359     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2360         gap_drop_link_key_for_bd_addr(bd_address);
2361     }
2362 #else
2363     UNUSED(status);
2364 #endif
2365 }
2366 
2367 #ifdef ENABLE_CLASSIC
2368 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2369     // SSP Controller
2370     if (features[6] & (1 << 3)){
2371         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2372     }
2373     // eSCO
2374     if (features[3] & (1<<7)){
2375         conn->remote_supported_features[0] |= 1;
2376     }
2377     // Extended features
2378     if (features[7] & (1<<7)){
2379         conn->remote_supported_features[0] |= 2;
2380     }
2381 }
2382 
2383 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2384     // SSP Host
2385     if (features[0] & (1 << 0)){
2386         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2387     }
2388     // SC Host
2389     if (features[0] & (1 << 3)){
2390         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2391     }
2392 }
2393 
2394 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2395     // SC Controller
2396     if (features[1] & (1 << 0)){
2397         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2398     }
2399 }
2400 
2401 static void hci_handle_remote_features_received(hci_connection_t * conn){
2402     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2403     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2404     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2405     if (conn->bonding_flags & BONDING_DEDICATED){
2406         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2407     }
2408 }
2409 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2410     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2411     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2412 }
2413 
2414 #endif
2415 
2416 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2417     // handle BT initialization
2418     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2419         hci_initializing_event_handler(packet, size);
2420     }
2421 
2422     // help with BT sleep
2423     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2424         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2425         && (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable))) {
2426         hci_initializing_next_state();
2427     }
2428 }
2429 
2430 #ifdef ENABLE_CLASSIC
2431 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2432     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2433     conn->encryption_key_size = encryption_key_size;
2434     gap_security_level_t security_level = gap_security_level_for_connection(conn);
2435 
2436     // trigger disconnect for dedicated bonding, skip emit security level as disconnect is pending
2437     if ((conn->bonding_flags & BONDING_DEDICATED) != 0){
2438         conn->bonding_flags &= ~BONDING_DEDICATED;
2439         conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2440         conn->bonding_status = security_level == 0 ? ERROR_CODE_INSUFFICIENT_SECURITY : ERROR_CODE_SUCCESS;
2441         return;
2442     }
2443 
2444     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2445         conn->requested_security_level = LEVEL_0;
2446         hci_emit_security_level(conn->con_handle, security_level);
2447         return;
2448     }
2449 
2450     // Request remote features if not already done
2451     hci_trigger_remote_features_for_connection(conn);
2452 
2453     // Request Authentication if not already done
2454     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2455     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2456 }
2457 #endif
2458 
2459 static void hci_store_local_supported_commands(const uint8_t * packet){
2460     // create mapping table
2461 #define X(name, offset, bit) { offset, bit },
2462     static struct {
2463         uint8_t byte_offset;
2464         uint8_t bit_position;
2465     } supported_hci_commands_map [] = {
2466         SUPPORTED_HCI_COMMANDS
2467     };
2468 #undef X
2469 
2470     // create names for debug purposes
2471 #ifdef ENABLE_LOG_DEBUG
2472 #define X(name, offset, bit) #name,
2473     static const char * command_names[] = {
2474         SUPPORTED_HCI_COMMANDS
2475     };
2476 #undef X
2477 #endif
2478 
2479     hci_stack->local_supported_commands = 0;
2480     const uint8_t * commands_map = &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1];
2481     uint16_t i;
2482     for (i = 0 ; i < SUPPORTED_HCI_COMMANDS_COUNT ; i++){
2483         if ((commands_map[supported_hci_commands_map[i].byte_offset] & (1 << supported_hci_commands_map[i].bit_position)) != 0){
2484 #ifdef ENABLE_LOG_DEBUG
2485             log_info("Command %s (%u) supported %u/%u", command_names[i], i, supported_hci_commands_map[i].byte_offset, supported_hci_commands_map[i].bit_position);
2486 #else
2487             log_info("Command 0x%02x supported %u/%u", i, supported_hci_commands_map[i].byte_offset, supported_hci_commands_map[i].bit_position);
2488 #endif
2489             hci_stack->local_supported_commands |= (1LU << i);
2490         }
2491     }
2492     log_info("Local supported commands summary %04x", hci_stack->local_supported_commands);
2493 }
2494 
2495 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2496     UNUSED(size);
2497 
2498     uint16_t manufacturer;
2499 #ifdef ENABLE_CLASSIC
2500     hci_con_handle_t handle;
2501     hci_connection_t * conn;
2502     uint8_t status;
2503 #endif
2504     // get num cmd packets - limit to 1 to reduce complexity
2505     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2506 
2507     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2508     switch (opcode){
2509         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2510             if (packet[5]) break;
2511             // terminate, name 248 chars
2512             packet[6+248] = 0;
2513             log_info("local name: %s", &packet[6]);
2514             break;
2515         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2516             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2517             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2518                 uint16_t acl_len = little_endian_read_16(packet, 6);
2519                 uint16_t sco_len = packet[8];
2520 
2521                 // determine usable ACL/SCO payload size
2522                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2523                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2524 
2525                 hci_stack->acl_packets_total_num = (uint8_t) little_endian_read_16(packet, 9);
2526                 hci_stack->sco_packets_total_num = (uint8_t) little_endian_read_16(packet, 11);
2527 
2528                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2529                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2530                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2531             }
2532             break;
2533         case HCI_OPCODE_HCI_READ_RSSI:
2534             if (packet[5] == ERROR_CODE_SUCCESS){
2535                 uint8_t event[5];
2536                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2537                 event[1] = 3;
2538                 (void)memcpy(&event[2], &packet[6], 3);
2539                 hci_emit_event(event, sizeof(event), 1);
2540             }
2541             break;
2542 #ifdef ENABLE_BLE
2543         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE_V2:
2544             hci_stack->le_iso_packets_length = little_endian_read_16(packet, 9);
2545             hci_stack->le_iso_packets_total_num = packet[11];
2546             log_info("hci_le_read_buffer_size_v2: iso size %u, iso count %u",
2547                      hci_stack->le_iso_packets_length, hci_stack->le_iso_packets_total_num);
2548 
2549             /* fall through */
2550 
2551         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2552             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2553             hci_stack->le_acl_packets_total_num = packet[8];
2554             // determine usable ACL payload size
2555             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2556                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2557             }
2558             log_info("hci_le_read_buffer_size: acl size %u, acl count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2559             break;
2560 #endif
2561 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2562         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2563             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2564             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2565             log_info("hci_le_read_maximum_data_length: tx octets %u, tx time %u us", hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
2566             break;
2567 #endif
2568 #ifdef ENABLE_LE_CENTRAL
2569         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2570             hci_stack->le_whitelist_capacity = packet[6];
2571             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2572             break;
2573 #endif
2574 #ifdef ENABLE_LE_PERIPHERAL
2575 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
2576         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_ADVERTISING_DATA_LENGTH:
2577             hci_stack->le_maximum_advertising_data_length = little_endian_read_16(packet, 6);
2578             break;
2579         case HCI_OPCODE_HCI_LE_SET_EXTENDED_ADVERTISING_PARAMETERS:
2580             if (hci_stack->le_advertising_set_in_current_command != 0) {
2581                 le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(hci_stack->le_advertising_set_in_current_command);
2582                 hci_stack->le_advertising_set_in_current_command = 0;
2583                 if (advertising_set == NULL) break;
2584                 uint8_t adv_status = packet[6];
2585                 uint8_t tx_power   = packet[7];
2586                 uint8_t event[] = { HCI_EVENT_META_GAP, 4, GAP_SUBEVENT_ADVERTISING_SET_INSTALLED, hci_stack->le_advertising_set_in_current_command, adv_status, tx_power };
2587                 if (adv_status == 0){
2588                     advertising_set->state |= LE_ADVERTISEMENT_STATE_PARAMS_SET;
2589                 }
2590                 hci_emit_event(event, sizeof(event), 1);
2591             }
2592             break;
2593         case HCI_OPCODE_HCI_LE_REMOVE_ADVERTISING_SET:
2594             if (hci_stack->le_advertising_set_in_current_command != 0) {
2595                 le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(hci_stack->le_advertising_set_in_current_command);
2596                 hci_stack->le_advertising_set_in_current_command = 0;
2597                 if (advertising_set == NULL) break;
2598                 uint8_t adv_status = packet[5];
2599                 uint8_t event[] = { HCI_EVENT_META_GAP, 3, GAP_SUBEVENT_ADVERTISING_SET_REMOVED, hci_stack->le_advertising_set_in_current_command, adv_status };
2600                 if (adv_status == 0){
2601                     btstack_linked_list_remove(&hci_stack->le_advertising_sets, (btstack_linked_item_t *) advertising_set);
2602                 }
2603                 hci_emit_event(event, sizeof(event), 1);
2604             }
2605             break;
2606 #endif
2607 #endif
2608         case HCI_OPCODE_HCI_READ_BD_ADDR:
2609             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2610             log_info("Local Address, Status: 0x%02x: Addr: %s", packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2611 #ifdef ENABLE_CLASSIC
2612             if (hci_stack->link_key_db){
2613                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2614             }
2615 #endif
2616             break;
2617 #ifdef ENABLE_CLASSIC
2618         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2619             hci_emit_discoverable_enabled(hci_stack->discoverable);
2620             break;
2621         case HCI_OPCODE_HCI_PERIODIC_INQUIRY_MODE:
2622             status = hci_event_command_complete_get_return_parameters(packet)[0];
2623             if (status == ERROR_CODE_SUCCESS) {
2624                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_PERIODIC;
2625             } else {
2626                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2627             }
2628             break;
2629         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2630         case HCI_OPCODE_HCI_EXIT_PERIODIC_INQUIRY_MODE:
2631             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2632                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2633                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2634                 hci_emit_event(event, sizeof(event), 1);
2635             }
2636             break;
2637 #endif
2638         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2639             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2640 
2641 #ifdef ENABLE_CLASSIC
2642             // determine usable ACL packet types based on host buffer size and supported features
2643             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2644             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2645 #endif
2646             // Classic/LE
2647             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2648             break;
2649         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2650             manufacturer = little_endian_read_16(packet, 10);
2651             // map Cypress to Broadcom
2652             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2653                 log_info("Treat Cypress as Broadcom");
2654                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2655                 little_endian_store_16(packet, 10, manufacturer);
2656             }
2657             hci_stack->manufacturer = manufacturer;
2658             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2659             break;
2660         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2661             hci_store_local_supported_commands(packet);
2662             break;
2663 #ifdef ENABLE_CLASSIC
2664         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2665             if (packet[5]) return;
2666             hci_stack->synchronous_flow_control_enabled = 1;
2667             break;
2668         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2669             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2670             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2671             conn   = hci_connection_for_handle(handle);
2672             if (conn != NULL) {
2673                 uint8_t key_size = 0;
2674                 if (status == 0){
2675                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2676                     log_info("Handle %04x key Size: %u", handle, key_size);
2677                 } else {
2678                     key_size = 1;
2679                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2680                 }
2681                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2682             }
2683             break;
2684         // assert pairing complete event is emitted.
2685         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2686         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2687         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2688         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2689             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2690             // lookup connection by gap pairing addr
2691             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2692             if (conn == NULL) break;
2693             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2694             break;
2695 
2696 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2697         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2698         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2699             uint8_t event[67];
2700             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2701             event[1] = 65;
2702             (void)memset(&event[2], 0, 65);
2703             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2704                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2705                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2706                     event[2] = 3;
2707                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2708                 } else {
2709                     event[2] = 1;
2710                 }
2711             }
2712             hci_emit_event(event, sizeof(event), 0);
2713             break;
2714         }
2715 
2716         // note: only needed if user does not provide OOB data
2717         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2718             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2719             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2720             if (conn == NULL) break;
2721             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2722             break;
2723 #endif
2724 #endif
2725 #ifdef ENABLE_BLE
2726 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
2727         case HCI_OPCODE_HCI_LE_ACCEPT_CIS_REQUEST:
2728         case HCI_OPCODE_HCI_LE_CREATE_CIS:
2729             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2730             if (status != ERROR_CODE_SUCCESS){
2731                 hci_iso_stream_requested_finalize();
2732             }
2733             break;
2734 #endif
2735 #endif
2736         default:
2737             break;
2738     }
2739 }
2740 
2741 #ifdef ENABLE_BLE
2742 static void event_handle_le_connection_complete(const uint8_t * packet){
2743 	bd_addr_t addr;
2744 	bd_addr_type_t addr_type;
2745 	hci_connection_t * conn;
2746 
2747 	// Connection management
2748 	reverse_bd_addr(&packet[8], addr);
2749 	addr_type = (bd_addr_type_t)packet[7];
2750 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2751 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2752 
2753 #ifdef ENABLE_LE_CENTRAL
2754 	// handle error: error is reported only to the initiator -> outgoing connection
2755 	if (packet[3]){
2756 
2757 		// handle cancelled outgoing connection
2758 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2759 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2760 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2761 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2762 		    // reset state
2763             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2764             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2765 			// get outgoing connection conn struct for direct connect
2766 			conn = gap_get_outgoing_connection();
2767 		}
2768 
2769 		// outgoing le connection establishment is done
2770 		if (conn){
2771 			// remove entry
2772 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2773 			btstack_memory_hci_connection_free( conn );
2774 		}
2775 		return;
2776 	}
2777 #endif
2778 
2779 	// on success, both hosts receive connection complete event
2780 	if (packet[6] == HCI_ROLE_MASTER){
2781 #ifdef ENABLE_LE_CENTRAL
2782 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2783 		// note: no hci_connection_t object exists yet for connect with whitelist
2784 		if (hci_is_le_connection_type(addr_type)){
2785 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2786 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2787 		}
2788 #endif
2789 	} else {
2790 #ifdef ENABLE_LE_PERIPHERAL
2791 		// if we're slave, it was an incoming connection, advertisements have stopped
2792         hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
2793 #endif
2794 	}
2795 
2796 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2797 	if (!conn){
2798 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2799 	}
2800 
2801 	// no memory, sorry.
2802 	if (!conn){
2803 		return;
2804 	}
2805 
2806 	conn->state = OPEN;
2807 	conn->role  = packet[6];
2808 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2809 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2810 
2811 #ifdef ENABLE_LE_PERIPHERAL
2812 	if (packet[6] == HCI_ROLE_SLAVE){
2813 		hci_update_advertisements_enabled_for_current_roles();
2814 	}
2815 #endif
2816 
2817     // init unenhanced att bearer mtu
2818     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2819     conn->att_connection.mtu_exchanged = false;
2820 
2821     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2822 
2823 	// restart timer
2824 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2825 	// btstack_run_loop_add_timer(&conn->timeout);
2826 
2827 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2828 
2829 	hci_emit_nr_connections_changed();
2830 }
2831 #endif
2832 
2833 #ifdef ENABLE_CLASSIC
2834 static bool hci_ssp_security_level_possible_for_io_cap(gap_security_level_t level, uint8_t io_cap_local, uint8_t io_cap_remote){
2835     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2836     // LEVEL_4 is tested by l2cap
2837     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2838     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2839     if (level >= LEVEL_3){
2840         // MITM not possible without keyboard or display
2841         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2842         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2843 
2844         // MITM possible if one side has keyboard and the other has keyboard or display
2845         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2846         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2847 
2848         // MITM not possible if one side has only display and other side has no keyboard
2849         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2850         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2851     }
2852     // LEVEL 2 requires SSP, which is a given
2853     return true;
2854 }
2855 
2856 static bool btstack_is_null(uint8_t * data, uint16_t size){
2857     uint16_t i;
2858     for (i=0; i < size ; i++){
2859         if (data[i] != 0) {
2860             return false;
2861         }
2862     }
2863     return true;
2864 }
2865 
2866 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2867     // get requested security level
2868     gap_security_level_t requested_security_level = conn->requested_security_level;
2869     if (hci_stack->gap_secure_connections_only_mode){
2870         requested_security_level = LEVEL_4;
2871     }
2872 
2873     // assess security: LEVEL 4 requires SC
2874     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2875     if ((requested_security_level == LEVEL_4) &&
2876         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2877         !hci_remote_sc_enabled(conn)){
2878         log_info("Level 4 required, but SC not supported -> abort");
2879         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2880         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2881         return;
2882     }
2883 
2884     // assess security based on io capabilities
2885     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2886         // responder: fully validate io caps of both sides as well as OOB data
2887         bool security_possible = false;
2888         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2889 
2890 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2891         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2892         // so we merge the OOB data availability
2893         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2894         if (conn->classic_oob_c_192 != NULL){
2895             have_oob_data |= 1;
2896         }
2897         if (conn->classic_oob_c_256 != NULL){
2898             have_oob_data |= 2;
2899         }
2900         // for up to Level 3, either P-192 as well as P-256 will do
2901         // if we don't support SC, then a) conn->classic_oob_c_256 will be NULL and b) remote should not report P-256 available
2902         // if remote does not SC, we should not receive P-256 data either
2903         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2904             security_possible = true;
2905         }
2906         // for Level 4, P-256 is needed
2907         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2908             security_possible = true;
2909         }
2910 #endif
2911 
2912         if (security_possible == false){
2913             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2914             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2915             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2916             return;
2917         }
2918     } else {
2919         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2920 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2921 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2922         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2923             log_info("Level 3+ required, but no input/output -> abort");
2924             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2925             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2926             return;
2927         }
2928 #endif
2929 #endif
2930     }
2931 
2932 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2933     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2934         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2935     } else {
2936         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2937     }
2938 #endif
2939 }
2940 
2941 #endif
2942 
2943 static void event_handler(uint8_t *packet, uint16_t size){
2944 
2945     uint16_t event_length = packet[1];
2946 
2947     // assert packet is complete
2948     if (size != (event_length + 2u)){
2949         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2950         return;
2951     }
2952 
2953     bd_addr_type_t addr_type;
2954     hci_con_handle_t handle;
2955     hci_connection_t * conn;
2956     int i;
2957     int create_connection_cmd;
2958 
2959 #ifdef ENABLE_CLASSIC
2960     hci_link_type_t link_type;
2961     bd_addr_t addr;
2962 #endif
2963 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
2964     hci_iso_stream_t * iso_stream;
2965 #endif
2966 
2967     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2968 
2969     switch (hci_event_packet_get_type(packet)) {
2970 
2971         case HCI_EVENT_COMMAND_COMPLETE:
2972             handle_command_complete_event(packet, size);
2973             break;
2974 
2975         case HCI_EVENT_COMMAND_STATUS:
2976             // get num cmd packets - limit to 1 to reduce complexity
2977             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2978 
2979             // check command status to detected failed outgoing connections
2980             create_connection_cmd = 0;
2981 #ifdef ENABLE_CLASSIC
2982             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2983                 create_connection_cmd = 1;
2984             }
2985             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_accept_synchronous_connection)){
2986                 create_connection_cmd = 1;
2987             }
2988 #endif
2989 #ifdef ENABLE_LE_CENTRAL
2990             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2991                 create_connection_cmd = 1;
2992             }
2993 #endif
2994             if (create_connection_cmd) {
2995                 uint8_t status = hci_event_command_status_get_status(packet);
2996                 addr_type = hci_stack->outgoing_addr_type;
2997                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2998                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), addr_type);
2999 
3000                 // reset outgoing address info
3001                 memset(hci_stack->outgoing_addr, 0, 6);
3002                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
3003 
3004                 // on error
3005                 if (status != ERROR_CODE_SUCCESS){
3006 #ifdef ENABLE_LE_CENTRAL
3007                     if (hci_is_le_connection_type(addr_type)){
3008                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3009                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3010                     }
3011 #endif
3012                     // error => outgoing connection failed
3013                     if (conn != NULL){
3014                         hci_handle_connection_failed(conn, status);
3015                     }
3016                 }
3017             }
3018 
3019 #ifdef ENABLE_CLASSIC
3020             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)){
3021                 uint8_t status = hci_event_command_status_get_status(packet);
3022                 log_info("command status (inquiry), status %x", status);
3023                 if (status == ERROR_CODE_SUCCESS) {
3024                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3025                 } else {
3026                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
3027                 }
3028             }
3029 #endif /* ENABLE_CLASSIC */
3030 #ifdef ENABLE_BLE
3031 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3032             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_cis) || HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_accept_cis_request)){
3033                 uint8_t status = hci_event_command_status_get_status(packet);
3034                 if (status == ERROR_CODE_SUCCESS){
3035                     hci_iso_stream_requested_confirm();
3036                 } else {
3037                     hci_iso_stream_requested_finalize();
3038                 }
3039             }
3040 #endif /* ENABLE_LE_ISOCHRONOUS_STREAMS */
3041 #endif /* ENABLE_BLE */
3042             break;
3043 
3044         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
3045             if (size < 3) return;
3046             uint16_t num_handles = packet[2];
3047             if (size != (3u + num_handles * 4u)) return;
3048             uint16_t offset = 3;
3049             for (i=0; i<num_handles;i++){
3050                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
3051                 offset += 2u;
3052                 uint16_t num_packets = little_endian_read_16(packet, offset);
3053                 offset += 2u;
3054 
3055                 conn = hci_connection_for_handle(handle);
3056                 if (!conn){
3057                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
3058                     continue;
3059                 }
3060 
3061                 if (conn->num_packets_sent >= num_packets){
3062                     conn->num_packets_sent -= num_packets;
3063                 } else {
3064                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
3065                     conn->num_packets_sent = 0;
3066                 }
3067                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
3068 
3069 #ifdef ENABLE_CLASSIC
3070                 // For SCO, we do the can_send_now_check here
3071                 hci_notify_if_sco_can_send_now();
3072 #endif
3073             }
3074             break;
3075         }
3076 
3077 #ifdef ENABLE_CLASSIC
3078         case HCI_EVENT_FLUSH_OCCURRED:
3079             // flush occurs only if automatic flush has been enabled by gap_enable_link_watchdog()
3080             handle = hci_event_flush_occurred_get_handle(packet);
3081             conn = hci_connection_for_handle(handle);
3082             if (conn) {
3083                 log_info("Flush occurred, disconnect 0x%04x", handle);
3084                 conn->state = SEND_DISCONNECT;
3085             }
3086             break;
3087 
3088         case HCI_EVENT_INQUIRY_COMPLETE:
3089             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
3090                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
3091                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
3092                 hci_emit_event(event, sizeof(event), 1);
3093             }
3094             break;
3095         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
3096             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
3097                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
3098             }
3099             break;
3100         case HCI_EVENT_CONNECTION_REQUEST:
3101             reverse_bd_addr(&packet[2], addr);
3102             link_type = (hci_link_type_t) packet[11];
3103 
3104             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
3105             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
3106                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
3107                 bd_addr_copy(hci_stack->decline_addr, addr);
3108                 break;
3109             }
3110 
3111             if (hci_stack->gap_classic_accept_callback != NULL){
3112                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
3113                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
3114                     bd_addr_copy(hci_stack->decline_addr, addr);
3115                     break;
3116                 }
3117             }
3118 
3119             // TODO: eval COD 8-10
3120             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
3121             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
3122             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3123             if (!conn) {
3124                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3125             }
3126             if (!conn) {
3127                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
3128                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
3129                 bd_addr_copy(hci_stack->decline_addr, addr);
3130                 hci_run();
3131                 // avoid event to higher layer
3132                 return;
3133             }
3134             conn->role  = HCI_ROLE_SLAVE;
3135             conn->state = RECEIVED_CONNECTION_REQUEST;
3136             // store info about eSCO
3137             if (link_type == HCI_LINK_TYPE_ESCO){
3138                 conn->remote_supported_features[0] |= 1;
3139             }
3140             hci_run();
3141             break;
3142 
3143         case HCI_EVENT_CONNECTION_COMPLETE:
3144             // Connection management
3145             reverse_bd_addr(&packet[5], addr);
3146             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
3147             addr_type = BD_ADDR_TYPE_ACL;
3148             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3149             if (conn) {
3150                 if (!packet[2]){
3151                     conn->state = OPEN;
3152                     conn->con_handle = little_endian_read_16(packet, 3);
3153 
3154                     // trigger write supervision timeout if we're master
3155                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
3156                         conn->gap_connection_tasks |= GAP_CONNECTION_TASK_WRITE_SUPERVISION_TIMEOUT;
3157                     }
3158 
3159                     // trigger write automatic flush timeout
3160                     if (hci_stack->automatic_flush_timeout != 0){
3161                         conn->gap_connection_tasks |= GAP_CONNECTION_TASK_WRITE_AUTOMATIC_FLUSH_TIMEOUT;
3162                     }
3163 
3164                     // restart timer
3165                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
3166                     btstack_run_loop_add_timer(&conn->timeout);
3167 
3168                     // trigger remote features for dedicated bonding
3169                     if ((conn->bonding_flags & BONDING_DEDICATED) != 0){
3170                         hci_trigger_remote_features_for_connection(conn);
3171                     }
3172 
3173                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
3174 
3175                     hci_emit_nr_connections_changed();
3176                 } else {
3177                     // connection failed
3178                     hci_handle_connection_failed(conn, packet[2]);
3179                 }
3180             }
3181             break;
3182 
3183         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
3184             reverse_bd_addr(&packet[5], addr);
3185             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
3186             log_info("Synchronous Connection Complete for %p (status=%u) %s", conn, packet[2], bd_addr_to_str(addr));
3187             if (packet[2]){
3188                 // connection failed
3189                 if (conn){
3190                     hci_handle_connection_failed(conn, packet[2]);
3191                 }
3192                 break;
3193             }
3194             if (!conn) {
3195                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
3196             }
3197             if (!conn) {
3198                 break;
3199             }
3200             conn->state = OPEN;
3201             conn->con_handle = little_endian_read_16(packet, 3);
3202 
3203 #ifdef ENABLE_SCO_OVER_HCI
3204             // update SCO
3205             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
3206                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
3207             }
3208             // trigger can send now
3209             if (hci_have_usb_transport()){
3210                 hci_stack->sco_can_send_now = true;
3211             }
3212 #endif
3213 #ifdef HAVE_SCO_TRANSPORT
3214             // configure sco transport
3215             if (hci_stack->sco_transport != NULL){
3216                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
3217                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
3218             }
3219 #endif
3220             break;
3221 
3222         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
3223             handle = little_endian_read_16(packet, 3);
3224             conn = hci_connection_for_handle(handle);
3225             if (!conn) break;
3226             if (!packet[2]){
3227                 const uint8_t * features = &packet[5];
3228                 hci_handle_remote_features_page_0(conn, features);
3229 
3230                 // read extended features if possible
3231                 if (hci_command_supported(SUPPORTED_HCI_COMMAND_READ_REMOTE_EXTENDED_FEATURES)
3232                 && ((conn->remote_supported_features[0] & 2) != 0)) {
3233                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3234                     break;
3235                 }
3236             }
3237             hci_handle_remote_features_received(conn);
3238             break;
3239 
3240         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
3241             handle = little_endian_read_16(packet, 3);
3242             conn = hci_connection_for_handle(handle);
3243             if (!conn) break;
3244             // status = ok, page = 1
3245             if (!packet[2]) {
3246                 uint8_t page_number = packet[5];
3247                 uint8_t maximum_page_number = packet[6];
3248                 const uint8_t * features = &packet[7];
3249                 bool done = false;
3250                 switch (page_number){
3251                     case 1:
3252                         hci_handle_remote_features_page_1(conn, features);
3253                         if (maximum_page_number >= 2){
3254                             // get Secure Connections (Controller) from Page 2 if available
3255                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
3256                         } else {
3257                             // otherwise, assume SC (Controller) == SC (Host)
3258                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
3259                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
3260                             }
3261                             done = true;
3262                         }
3263                         break;
3264                     case 2:
3265                         hci_handle_remote_features_page_2(conn, features);
3266                         done = true;
3267                         break;
3268                     default:
3269                         break;
3270                 }
3271                 if (!done) break;
3272             }
3273             hci_handle_remote_features_received(conn);
3274             break;
3275 
3276         case HCI_EVENT_LINK_KEY_REQUEST:
3277 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
3278             hci_event_link_key_request_get_bd_addr(packet, addr);
3279             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3280             if (!conn) break;
3281 
3282             // lookup link key in db if not cached
3283             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
3284                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
3285             }
3286 
3287             // response sent by hci_run()
3288             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
3289 #endif
3290             break;
3291 
3292         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
3293             hci_event_link_key_request_get_bd_addr(packet, addr);
3294             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3295             if (!conn) break;
3296 
3297             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
3298 
3299             // CVE-2020-26555: ignore NULL link key
3300             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
3301             if (btstack_is_null(&packet[8], 16)) break;
3302 
3303             link_key_type_t link_key_type = (link_key_type_t)packet[24];
3304             // Change Connection Encryption keeps link key type
3305             if (link_key_type != CHANGED_COMBINATION_KEY){
3306                 conn->link_key_type = link_key_type;
3307             }
3308 
3309             // cache link key. link keys stored in little-endian format for legacy reasons
3310             memcpy(&conn->link_key, &packet[8], 16);
3311 
3312             // only store link key:
3313             // - if bondable enabled
3314             if (hci_stack->bondable == false) break;
3315             // - if security level sufficient
3316             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
3317             // - for SSP, also check if remote side requested bonding as well
3318             if (conn->link_key_type != COMBINATION_KEY){
3319                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3320                 if (!remote_bonding){
3321                     break;
3322                 }
3323             }
3324             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
3325             break;
3326         }
3327 
3328         case HCI_EVENT_PIN_CODE_REQUEST:
3329             hci_event_pin_code_request_get_bd_addr(packet, addr);
3330             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3331             if (!conn) break;
3332 
3333             hci_pairing_started(conn, false);
3334             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
3335             if (!hci_stack->bondable ){
3336                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
3337                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
3338                 hci_run();
3339                 return;
3340             }
3341             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
3342             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
3343                 log_info("Level 4 required, but SC not supported -> abort");
3344                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
3345                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
3346                 hci_run();
3347                 return;
3348             }
3349             break;
3350 
3351         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
3352             hci_event_io_capability_response_get_bd_addr(packet, addr);
3353             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3354             if (!conn) break;
3355 
3356             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
3357             hci_pairing_started(conn, true);
3358             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
3359             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
3360 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3361             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
3362 #endif
3363             break;
3364 
3365         case HCI_EVENT_IO_CAPABILITY_REQUEST:
3366             hci_event_io_capability_response_get_bd_addr(packet, addr);
3367             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3368             if (!conn) break;
3369 
3370             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
3371             hci_connection_timestamp(conn);
3372             hci_pairing_started(conn, true);
3373             break;
3374 
3375 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3376         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
3377             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
3378             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3379             if (!conn) break;
3380 
3381             hci_connection_timestamp(conn);
3382 
3383             hci_pairing_started(conn, true);
3384 
3385             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
3386             break;
3387 #endif
3388 
3389         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
3390             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
3391             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3392             if (!conn) break;
3393             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
3394                 if (hci_stack->ssp_auto_accept){
3395                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
3396                 };
3397             } else {
3398                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
3399                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
3400                 // don't forward event to app
3401                 hci_run();
3402                 return;
3403             }
3404             break;
3405 
3406         case HCI_EVENT_USER_PASSKEY_REQUEST:
3407             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
3408             if (hci_stack->ssp_auto_accept){
3409                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
3410             };
3411             break;
3412 
3413         case HCI_EVENT_MODE_CHANGE:
3414             handle = hci_event_mode_change_get_handle(packet);
3415             conn = hci_connection_for_handle(handle);
3416             if (!conn) break;
3417             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3418             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3419             break;
3420 #endif
3421 
3422         case HCI_EVENT_ENCRYPTION_CHANGE:
3423         case HCI_EVENT_ENCRYPTION_CHANGE_V2:
3424             handle = hci_event_encryption_change_get_connection_handle(packet);
3425             conn = hci_connection_for_handle(handle);
3426             if (!conn) break;
3427             if (hci_event_encryption_change_get_status(packet) == 0u) {
3428                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3429                 if (encryption_enabled){
3430                     if (hci_is_le_connection(conn)){
3431                         // For LE, we accept connection as encrypted
3432                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3433                     }
3434 #ifdef ENABLE_CLASSIC
3435                     else {
3436 
3437                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3438                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type);
3439                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3440                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3441                             log_info("SC during pairing, but only E0 now -> abort");
3442                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3443                             break;
3444                         }
3445 
3446                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3447                         if (connected_uses_aes_ccm){
3448                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3449                         }
3450 
3451 #ifdef ENABLE_TESTING_SUPPORT
3452                         // work around for issue with PTS dongle
3453                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3454 #endif
3455                         // validate encryption key size
3456                         if (hci_event_packet_get_type(packet) == HCI_EVENT_ENCRYPTION_CHANGE_V2) {
3457                             uint8_t encryption_key_size = hci_event_encryption_change_v2_get_encryption_key_size(packet);
3458                             // already got encryption key size
3459                             hci_handle_read_encryption_key_size_complete(conn, encryption_key_size);
3460                         } else {
3461                             if (hci_command_supported(SUPPORTED_HCI_COMMAND_READ_ENCRYPTION_KEY_SIZE)) {
3462                                 // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3463                                 conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3464                             } else {
3465                                 // if not, pretend everything is perfect
3466                                 hci_handle_read_encryption_key_size_complete(conn, 16);
3467                             }
3468                         }
3469                     }
3470 #endif
3471                 } else {
3472                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3473                 }
3474             } else {
3475                 uint8_t status = hci_event_encryption_change_get_status(packet);
3476                 if ((conn->bonding_flags & BONDING_DEDICATED) != 0){
3477                     conn->bonding_flags &= ~BONDING_DEDICATED;
3478                     conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3479                     conn->bonding_status = status;
3480                 }
3481             }
3482 
3483             break;
3484 
3485 #ifdef ENABLE_CLASSIC
3486         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3487             handle = hci_event_authentication_complete_get_connection_handle(packet);
3488             conn = hci_connection_for_handle(handle);
3489             if (!conn) break;
3490 
3491             // clear authentication active flag
3492             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3493             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3494 
3495             // authenticated only if auth status == 0
3496             if (hci_event_authentication_complete_get_status(packet) == 0){
3497                 // authenticated
3498                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3499 
3500                 // If not already encrypted, start encryption
3501                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3502                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3503                     break;
3504                 }
3505             }
3506 
3507             // emit updated security level
3508             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3509             break;
3510 
3511         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3512             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3513             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3514             if (!conn) break;
3515 
3516             // treat successfully paired connection as authenticated
3517             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3518                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3519             }
3520 
3521             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3522             break;
3523 #endif
3524 
3525         // HCI_EVENT_DISCONNECTION_COMPLETE
3526         // has been split, to first notify stack before shutting connection down
3527         // see end of function, too.
3528         case HCI_EVENT_DISCONNECTION_COMPLETE:
3529             if (packet[2]) break;   // status != 0
3530             handle = little_endian_read_16(packet, 3);
3531             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3532             if (hci_stack->acl_fragmentation_total_size > 0u) {
3533                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3534                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3535                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3536                     hci_stack->acl_fragmentation_total_size = 0;
3537                     hci_stack->acl_fragmentation_pos = 0;
3538                     if (release_buffer){
3539                         hci_release_packet_buffer();
3540                     }
3541                 }
3542             }
3543 
3544 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3545             // drop outgoing ISO fragments if it is for closed connection and release buffer if tx not active
3546             if (hci_stack->iso_fragmentation_total_size > 0u) {
3547                 if (handle == READ_ISO_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3548                     int release_buffer = hci_stack->iso_fragmentation_tx_active == 0u;
3549                     log_info("drop fragmented ISO data for closed connection, release buffer %u", release_buffer);
3550                     hci_stack->iso_fragmentation_total_size = 0;
3551                     hci_stack->iso_fragmentation_pos = 0;
3552                     if (release_buffer){
3553                         hci_release_packet_buffer();
3554                     }
3555                 }
3556             }
3557 
3558             // finalize iso stream if handle matches
3559             iso_stream = hci_iso_stream_for_cis_handle(handle);
3560             if (iso_stream != NULL){
3561                 hci_iso_stream_finalize(iso_stream);
3562                 break;
3563             }
3564 #endif
3565 
3566             conn = hci_connection_for_handle(handle);
3567             if (!conn) break;
3568 #ifdef ENABLE_CLASSIC
3569             // pairing failed if it was ongoing
3570             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3571 #endif
3572 
3573             // emit dedicatd bonding event
3574             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3575                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3576             }
3577 
3578             // mark connection for shutdown, stop timers, reset state
3579             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3580             hci_connection_stop_timer(conn);
3581             hci_connection_init(conn);
3582 
3583 #ifdef ENABLE_BLE
3584 #ifdef ENABLE_LE_PERIPHERAL
3585             // re-enable advertisements for le connections if active
3586             if (hci_is_le_connection(conn)){
3587                 hci_update_advertisements_enabled_for_current_roles();
3588             }
3589 #endif
3590 #endif
3591             break;
3592 
3593         case HCI_EVENT_HARDWARE_ERROR:
3594             log_error("Hardware Error: 0x%02x", packet[2]);
3595             if (hci_stack->hardware_error_callback){
3596                 (*hci_stack->hardware_error_callback)(packet[2]);
3597             } else {
3598                 // if no special requests, just reboot stack
3599                 hci_power_control_off();
3600                 hci_power_control_on();
3601             }
3602             break;
3603 
3604 #ifdef ENABLE_CLASSIC
3605         case HCI_EVENT_ROLE_CHANGE:
3606             if (packet[2]) break;   // status != 0
3607             reverse_bd_addr(&packet[3], addr);
3608             addr_type = BD_ADDR_TYPE_ACL;
3609             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3610             if (!conn) break;
3611             conn->role = packet[9];
3612             break;
3613 #endif
3614 
3615         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3616             // release packet buffer only for asynchronous transport and if there are not further fragments
3617             if (hci_transport_synchronous()) {
3618                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3619                 return; // instead of break: to avoid re-entering hci_run()
3620             }
3621             hci_stack->acl_fragmentation_tx_active = 0;
3622 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3623             hci_stack->iso_fragmentation_tx_active = 0;
3624             if (hci_stack->iso_fragmentation_total_size) break;
3625 #endif
3626             if (hci_stack->acl_fragmentation_total_size) break;
3627             hci_release_packet_buffer();
3628 
3629             // L2CAP receives this event via the hci_emit_event below
3630 
3631 #ifdef ENABLE_CLASSIC
3632             // For SCO, we do the can_send_now_check here
3633             hci_notify_if_sco_can_send_now();
3634 #endif
3635             break;
3636 
3637 #ifdef ENABLE_CLASSIC
3638         case HCI_EVENT_SCO_CAN_SEND_NOW:
3639             // For SCO, we do the can_send_now_check here
3640             hci_stack->sco_can_send_now = true;
3641             hci_notify_if_sco_can_send_now();
3642             return;
3643 
3644         // explode inquriy results for easier consumption
3645         case HCI_EVENT_INQUIRY_RESULT:
3646         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3647         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3648             gap_inquiry_explode(packet, size);
3649             break;
3650 #endif
3651 
3652 #ifdef ENABLE_BLE
3653         case HCI_EVENT_LE_META:
3654             switch (packet[2]){
3655 #ifdef ENABLE_LE_CENTRAL
3656                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3657                     if (!hci_stack->le_scanning_enabled) break;
3658                     le_handle_advertisement_report(packet, size);
3659                     break;
3660 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
3661                 case HCI_SUBEVENT_LE_EXTENDED_ADVERTISING_REPORT:
3662                     if (!hci_stack->le_scanning_enabled) break;
3663                     le_handle_extended_advertisement_report(packet, size);
3664                     break;
3665 #endif
3666 #endif
3667                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3668 					event_handle_le_connection_complete(packet);
3669                     break;
3670 
3671                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3672                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3673                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3674                     conn = hci_connection_for_handle(handle);
3675                     if (!conn) break;
3676                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3677                     break;
3678 
3679                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3680                     // connection
3681                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3682                     conn = hci_connection_for_handle(handle);
3683                     if (conn) {
3684                         // read arguments
3685                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3686                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3687                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3688                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3689 
3690                         // validate against current connection parameter range
3691                         le_connection_parameter_range_t existing_range;
3692                         gap_get_connection_parameter_range(&existing_range);
3693                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3694                         if (update_parameter){
3695                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3696                             conn->le_conn_interval_min = le_conn_interval_min;
3697                             conn->le_conn_interval_max = le_conn_interval_max;
3698                             conn->le_conn_latency = le_conn_latency;
3699                             conn->le_supervision_timeout = le_supervision_timeout;
3700                         } else {
3701                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3702                         }
3703                     }
3704                     break;
3705 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3706                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3707                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3708                     conn = hci_connection_for_handle(handle);
3709                     if (conn) {
3710                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3711                     }
3712                     break;
3713 #endif
3714 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3715                 case HCI_SUBEVENT_LE_CIS_ESTABLISHED:
3716                     handle = hci_subevent_le_cis_established_get_connection_handle(packet);
3717                     iso_stream = hci_iso_stream_for_cis_handle(handle);
3718                     if (iso_stream){
3719                         uint8_t status = hci_subevent_le_cis_established_get_status(packet);
3720                         if (status == ERROR_CODE_SUCCESS){
3721                             iso_stream->state = HCI_ISO_STREAM_STATE_ESTABLISHED;
3722                         } else {
3723                             hci_iso_stream_finalize(iso_stream);
3724                         }
3725                     }
3726 #endif
3727                 default:
3728                     break;
3729             }
3730             break;
3731 #endif
3732         case HCI_EVENT_VENDOR_SPECIFIC:
3733             // Vendor specific commands often create vendor specific event instead of num completed packets
3734             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3735             switch (hci_stack->manufacturer){
3736                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3737                     hci_stack->num_cmd_packets = 1;
3738                     break;
3739                 default:
3740                     break;
3741             }
3742             break;
3743         default:
3744             break;
3745     }
3746 
3747     handle_event_for_current_stack_state(packet, size);
3748 
3749     // notify upper stack
3750 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3751 
3752     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3753     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3754 		handle = little_endian_read_16(packet, 3);
3755 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3756 		// discard connection if app did not trigger a reconnect in the event handler
3757 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3758 			hci_shutdown_connection(aConn);
3759 		}
3760     }
3761 
3762 	// execute main loop
3763 	hci_run();
3764 }
3765 
3766 #ifdef ENABLE_CLASSIC
3767 
3768 #ifdef ENABLE_SCO_OVER_HCI
3769 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3770 static void sco_schedule_tx(hci_connection_t * conn);
3771 
3772 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3773     log_debug("SCO TX Timeout");
3774     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3775     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3776     if (!conn) return;
3777 
3778     // trigger send
3779     conn->sco_tx_ready = 1;
3780     // extra packet if CVSD but SCO buffer is too short
3781     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3782         conn->sco_tx_ready++;
3783     }
3784     hci_notify_if_sco_can_send_now();
3785 }
3786 
3787 
3788 #define SCO_TX_AFTER_RX_MS (6)
3789 
3790 static void sco_schedule_tx(hci_connection_t * conn){
3791 
3792     uint32_t now = btstack_run_loop_get_time_ms();
3793     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3794     int time_delta_ms = sco_tx_ms - now;
3795 
3796     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3797 
3798     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3799     btstack_run_loop_remove_timer(timer);
3800     btstack_run_loop_set_timer(timer, time_delta_ms);
3801     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3802     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3803     btstack_run_loop_add_timer(timer);
3804 }
3805 #endif
3806 
3807 static void sco_handler(uint8_t * packet, uint16_t size){
3808     // lookup connection struct
3809     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3810     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3811     if (!conn) return;
3812 
3813 #ifdef ENABLE_SCO_OVER_HCI
3814     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3815     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3816         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3817             packet[2] = 0x3c;
3818             memmove(&packet[3], &packet[23], 63);
3819             size = 63;
3820         }
3821     }
3822 
3823     if (hci_have_usb_transport()){
3824         // Nothing to do
3825     } else {
3826         // log_debug("sco flow %u, handle 0x%04x, packets sent %u, bytes send %u", hci_stack->synchronous_flow_control_enabled, (int) con_handle, conn->num_packets_sent, conn->num_sco_bytes_sent);
3827         if (hci_stack->synchronous_flow_control_enabled == 0){
3828             uint32_t now = btstack_run_loop_get_time_ms();
3829 
3830             if (!conn->sco_rx_valid){
3831                 // ignore first 10 packets
3832                 conn->sco_rx_count++;
3833                 // log_debug("sco rx count %u", conn->sco_rx_count);
3834                 if (conn->sco_rx_count == 10) {
3835                     // use first timestamp as is and pretent it just started
3836                     conn->sco_rx_ms = now;
3837                     conn->sco_rx_valid = 1;
3838                     conn->sco_rx_count = 0;
3839                     sco_schedule_tx(conn);
3840                 }
3841             } else {
3842                 // track expected arrival timme
3843                 conn->sco_rx_count++;
3844                 conn->sco_rx_ms += 7;
3845                 int delta = (int32_t) (now - conn->sco_rx_ms);
3846                 if (delta > 0){
3847                     conn->sco_rx_ms++;
3848                 }
3849                 // log_debug("sco rx %u", conn->sco_rx_ms);
3850                 sco_schedule_tx(conn);
3851             }
3852         }
3853     }
3854 #endif
3855 
3856     // deliver to app
3857     if (hci_stack->sco_packet_handler) {
3858         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3859     }
3860 
3861 #ifdef HAVE_SCO_TRANSPORT
3862     // We can send one packet for each received packet
3863     conn->sco_tx_ready++;
3864     hci_notify_if_sco_can_send_now();
3865 #endif
3866 
3867 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3868     conn->num_packets_completed++;
3869     hci_stack->host_completed_packets = 1;
3870     hci_run();
3871 #endif
3872 }
3873 #endif
3874 
3875 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3876     hci_dump_packet(packet_type, 1, packet, size);
3877     switch (packet_type) {
3878         case HCI_EVENT_PACKET:
3879             event_handler(packet, size);
3880             break;
3881         case HCI_ACL_DATA_PACKET:
3882             acl_handler(packet, size);
3883             break;
3884 #ifdef ENABLE_CLASSIC
3885         case HCI_SCO_DATA_PACKET:
3886             sco_handler(packet, size);
3887             break;
3888 #endif
3889 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3890         case HCI_ISO_DATA_PACKET:
3891             hci_iso_packet_handler(packet, size);
3892             break;
3893 #endif
3894         default:
3895             break;
3896     }
3897 }
3898 
3899 /**
3900  * @brief Add event packet handler.
3901  */
3902 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3903     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3904 }
3905 
3906 /**
3907  * @brief Remove event packet handler.
3908  */
3909 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3910     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3911 }
3912 
3913 /** Register HCI packet handlers */
3914 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3915     hci_stack->acl_packet_handler = handler;
3916 }
3917 
3918 #ifdef ENABLE_CLASSIC
3919 /**
3920  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3921  */
3922 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3923     hci_stack->sco_packet_handler = handler;
3924 }
3925 #endif
3926 
3927 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
3928 void hci_register_iso_packet_handler(btstack_packet_handler_t handler){
3929     hci_stack->iso_packet_handler = handler;
3930 }
3931 #endif
3932 
3933 static void hci_state_reset(void){
3934     // no connections yet
3935     hci_stack->connections = NULL;
3936 
3937     // keep discoverable/connectable as this has been requested by the client(s)
3938     // hci_stack->discoverable = 0;
3939     // hci_stack->connectable = 0;
3940     // hci_stack->bondable = 1;
3941     // hci_stack->own_addr_type = 0;
3942 
3943     // buffer is free
3944     hci_stack->hci_packet_buffer_reserved = false;
3945 
3946     // no pending cmds
3947     hci_stack->decline_reason = 0;
3948 
3949     hci_stack->secure_connections_active = false;
3950 
3951 #ifdef ENABLE_CLASSIC
3952     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3953     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3954 
3955     hci_stack->gap_tasks_classic =
3956             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3957             GAP_TASK_SET_CLASS_OF_DEVICE |
3958             GAP_TASK_SET_LOCAL_NAME |
3959             GAP_TASK_SET_EIR_DATA |
3960             GAP_TASK_WRITE_SCAN_ENABLE |
3961             GAP_TASK_WRITE_PAGE_TIMEOUT;
3962 #endif
3963 
3964 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3965     hci_stack->classic_read_local_oob_data = false;
3966     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3967 #endif
3968 
3969     // LE
3970 #ifdef ENABLE_BLE
3971     memset(hci_stack->le_random_address, 0, 6);
3972     hci_stack->le_random_address_set = 0;
3973 #endif
3974 #ifdef ENABLE_LE_CENTRAL
3975     hci_stack->le_scanning_active  = false;
3976     hci_stack->le_scanning_param_update = true;
3977     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3978     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3979     hci_stack->le_whitelist_capacity = 0;
3980 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
3981     hci_stack->le_periodic_terminate_sync_handle = HCI_CON_HANDLE_INVALID;
3982 #endif
3983 #endif
3984 #ifdef ENABLE_LE_PERIPHERAL
3985     hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
3986     if ((hci_stack->le_advertisements_state & LE_ADVERTISEMENT_STATE_PARAMS_SET) != 0){
3987         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3988     }
3989     if (hci_stack->le_advertisements_data != NULL){
3990         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3991     }
3992 #endif
3993 }
3994 
3995 #ifdef ENABLE_CLASSIC
3996 /**
3997  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3998  */
3999 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
4000     // store and open remote device db
4001     hci_stack->link_key_db = link_key_db;
4002     if (hci_stack->link_key_db) {
4003         hci_stack->link_key_db->open();
4004     }
4005 }
4006 #endif
4007 
4008 void hci_init(const hci_transport_t *transport, const void *config){
4009 
4010 #ifdef HAVE_MALLOC
4011     if (!hci_stack) {
4012         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
4013     }
4014 #else
4015     hci_stack = &hci_stack_static;
4016 #endif
4017     memset(hci_stack, 0, sizeof(hci_stack_t));
4018 
4019     // reference to use transport layer implementation
4020     hci_stack->hci_transport = transport;
4021 
4022     // reference to used config
4023     hci_stack->config = config;
4024 
4025     // setup pointer for outgoing packet buffer
4026     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
4027 
4028     // max acl payload size defined in config.h
4029     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
4030 
4031     // register packet handlers with transport
4032     transport->register_packet_handler(&packet_handler);
4033 
4034     hci_stack->state = HCI_STATE_OFF;
4035 
4036     // class of device
4037     hci_stack->class_of_device = 0x007a020c; // Smartphone
4038 
4039     // bondable by default
4040     hci_stack->bondable = 1;
4041 
4042 #ifdef ENABLE_CLASSIC
4043     // classic name
4044     hci_stack->local_name = default_classic_name;
4045 
4046     // Master slave policy
4047     hci_stack->master_slave_policy = 1;
4048 
4049     // Allow Role Switch
4050     hci_stack->allow_role_switch = 1;
4051 
4052     // Default / minimum security level = 2
4053     hci_stack->gap_security_level = LEVEL_2;
4054 
4055     // Default Security Mode 4
4056     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
4057 
4058     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
4059     hci_stack->gap_required_encyrption_key_size = 7;
4060 
4061     // Link Supervision Timeout
4062     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
4063 
4064 #endif
4065 
4066     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
4067     hci_stack->ssp_enable = 1;
4068     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
4069     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4070     hci_stack->ssp_auto_accept = 1;
4071 
4072     // Secure Connections: enable (requires support from Controller)
4073     hci_stack->secure_connections_enable = true;
4074 
4075     // voice setting - signed 16 bit pcm data with CVSD over the air
4076     hci_stack->sco_voice_setting = 0x60;
4077 
4078 #ifdef ENABLE_LE_CENTRAL
4079     // connection parameter to use for outgoing connections
4080     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
4081     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
4082     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
4083     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
4084     hci_stack->le_connection_latency      = 4;         // 4
4085     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
4086     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
4087     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
4088 
4089     // default LE Scanning
4090     hci_stack->le_scan_type     =   0x1; // active
4091     hci_stack->le_scan_interval = 0x1e0; // 300 ms
4092     hci_stack->le_scan_window   =  0x30; //  30 ms
4093 #endif
4094 
4095 #ifdef ENABLE_LE_PERIPHERAL
4096     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
4097 #endif
4098 
4099     // connection parameter range used to answer connection parameter update requests in l2cap
4100     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
4101     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
4102     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
4103     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
4104     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
4105     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
4106 
4107     hci_state_reset();
4108 }
4109 
4110 void hci_deinit(void){
4111     btstack_run_loop_remove_timer(&hci_stack->timeout);
4112 #ifdef HAVE_MALLOC
4113     if (hci_stack) {
4114         free(hci_stack);
4115     }
4116 #endif
4117     hci_stack = NULL;
4118 
4119 #ifdef ENABLE_CLASSIC
4120     disable_l2cap_timeouts = 0;
4121 #endif
4122 }
4123 
4124 /**
4125  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
4126  */
4127 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
4128     hci_stack->chipset = chipset_driver;
4129 
4130     // reset chipset driver - init is also called on power_up
4131     if (hci_stack->chipset && hci_stack->chipset->init){
4132         hci_stack->chipset->init(hci_stack->config);
4133     }
4134 }
4135 
4136 /**
4137  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
4138  */
4139 void hci_set_control(const btstack_control_t *hardware_control){
4140     // references to used control implementation
4141     hci_stack->control = hardware_control;
4142     // init with transport config
4143     hardware_control->init(hci_stack->config);
4144 }
4145 
4146 static void hci_discard_connections(void){
4147     btstack_linked_list_iterator_t lit;
4148     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
4149     while (btstack_linked_list_iterator_has_next(&lit)){
4150         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
4151         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
4152         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
4153         hci_shutdown_connection(connection);
4154     }
4155 }
4156 
4157 void hci_close(void){
4158 
4159 #ifdef ENABLE_CLASSIC
4160     // close remote device db
4161     if (hci_stack->link_key_db) {
4162         hci_stack->link_key_db->close();
4163     }
4164 #endif
4165 
4166     hci_discard_connections();
4167 
4168     hci_power_control(HCI_POWER_OFF);
4169 
4170 #ifdef HAVE_MALLOC
4171     free(hci_stack);
4172 #endif
4173     hci_stack = NULL;
4174 }
4175 
4176 #ifdef HAVE_SCO_TRANSPORT
4177 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
4178     hci_stack->sco_transport = sco_transport;
4179     sco_transport->register_packet_handler(&packet_handler);
4180 }
4181 #endif
4182 
4183 #ifdef ENABLE_CLASSIC
4184 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
4185     // validate ranage and set
4186     if (encryption_key_size < 7)  return;
4187     if (encryption_key_size > 16) return;
4188     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
4189 }
4190 
4191 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
4192     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
4193         hci_stack->gap_security_mode = security_mode;
4194         return ERROR_CODE_SUCCESS;
4195     } else {
4196         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
4197     }
4198 }
4199 
4200 gap_security_mode_t gap_get_security_mode(void){
4201     return hci_stack->gap_security_mode;
4202 }
4203 
4204 void gap_set_security_level(gap_security_level_t security_level){
4205     hci_stack->gap_security_level = security_level;
4206 }
4207 
4208 gap_security_level_t gap_get_security_level(void){
4209     if (hci_stack->gap_secure_connections_only_mode){
4210         return LEVEL_4;
4211     }
4212     return hci_stack->gap_security_level;
4213 }
4214 
4215 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
4216     hci_stack->gap_minimal_service_security_level = security_level;
4217 }
4218 
4219 void gap_set_secure_connections_only_mode(bool enable){
4220     hci_stack->gap_secure_connections_only_mode = enable;
4221 }
4222 
4223 bool gap_get_secure_connections_only_mode(void){
4224     return hci_stack->gap_secure_connections_only_mode;
4225 }
4226 #endif
4227 
4228 #ifdef ENABLE_CLASSIC
4229 void gap_set_class_of_device(uint32_t class_of_device){
4230     hci_stack->class_of_device = class_of_device;
4231     hci_stack->gap_tasks_classic |= GAP_TASK_SET_CLASS_OF_DEVICE;
4232     hci_run();
4233 }
4234 
4235 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
4236     hci_stack->default_link_policy_settings = default_link_policy_settings;
4237     hci_stack->gap_tasks_classic |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
4238     hci_run();
4239 }
4240 
4241 void gap_set_allow_role_switch(bool allow_role_switch){
4242     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
4243 }
4244 
4245 uint8_t hci_get_allow_role_switch(void){
4246     return  hci_stack->allow_role_switch;
4247 }
4248 
4249 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
4250     hci_stack->link_supervision_timeout = link_supervision_timeout;
4251 }
4252 
4253 void gap_enable_link_watchdog(uint16_t timeout_ms){
4254     hci_stack->automatic_flush_timeout = btstack_min(timeout_ms, 1280) * 8 / 5; // divide by 0.625
4255 }
4256 
4257 uint16_t hci_automatic_flush_timeout(void){
4258     return hci_stack->automatic_flush_timeout;
4259 }
4260 
4261 void hci_disable_l2cap_timeout_check(void){
4262     disable_l2cap_timeouts = 1;
4263 }
4264 #endif
4265 
4266 #ifndef HAVE_HOST_CONTROLLER_API
4267 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
4268 void hci_set_bd_addr(bd_addr_t addr){
4269     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
4270     hci_stack->custom_bd_addr_set = 1;
4271 }
4272 #endif
4273 
4274 // State-Module-Driver overview
4275 // state                    module  low-level
4276 // HCI_STATE_OFF             off      close
4277 // HCI_STATE_INITIALIZING,   on       open
4278 // HCI_STATE_WORKING,        on       open
4279 // HCI_STATE_HALTING,        on       open
4280 // HCI_STATE_SLEEPING,    off/sleep   close
4281 // HCI_STATE_FALLING_ASLEEP  on       open
4282 
4283 static int hci_power_control_on(void){
4284 
4285     // power on
4286     int err = 0;
4287     if (hci_stack->control && hci_stack->control->on){
4288         err = (*hci_stack->control->on)();
4289     }
4290     if (err){
4291         log_error( "POWER_ON failed");
4292         hci_emit_hci_open_failed();
4293         return err;
4294     }
4295 
4296     // int chipset driver
4297     if (hci_stack->chipset && hci_stack->chipset->init){
4298         hci_stack->chipset->init(hci_stack->config);
4299     }
4300 
4301     // init transport
4302     if (hci_stack->hci_transport->init){
4303         hci_stack->hci_transport->init(hci_stack->config);
4304     }
4305 
4306     // open transport
4307     err = hci_stack->hci_transport->open();
4308     if (err){
4309         log_error( "HCI_INIT failed, turning Bluetooth off again");
4310         if (hci_stack->control && hci_stack->control->off){
4311             (*hci_stack->control->off)();
4312         }
4313         hci_emit_hci_open_failed();
4314         return err;
4315     }
4316     return 0;
4317 }
4318 
4319 static void hci_power_control_off(void){
4320 
4321     log_info("hci_power_control_off");
4322 
4323     // close low-level device
4324     hci_stack->hci_transport->close();
4325 
4326     log_info("hci_power_control_off - hci_transport closed");
4327 
4328     // power off
4329     if (hci_stack->control && hci_stack->control->off){
4330         (*hci_stack->control->off)();
4331     }
4332 
4333     log_info("hci_power_control_off - control closed");
4334 
4335     hci_stack->state = HCI_STATE_OFF;
4336 }
4337 
4338 static void hci_power_control_sleep(void){
4339 
4340     log_info("hci_power_control_sleep");
4341 
4342 #if 0
4343     // don't close serial port during sleep
4344 
4345     // close low-level device
4346     hci_stack->hci_transport->close(hci_stack->config);
4347 #endif
4348 
4349     // sleep mode
4350     if (hci_stack->control && hci_stack->control->sleep){
4351         (*hci_stack->control->sleep)();
4352     }
4353 
4354     hci_stack->state = HCI_STATE_SLEEPING;
4355 }
4356 
4357 static int hci_power_control_wake(void){
4358 
4359     log_info("hci_power_control_wake");
4360 
4361     // wake on
4362     if (hci_stack->control && hci_stack->control->wake){
4363         (*hci_stack->control->wake)();
4364     }
4365 
4366 #if 0
4367     // open low-level device
4368     int err = hci_stack->hci_transport->open(hci_stack->config);
4369     if (err){
4370         log_error( "HCI_INIT failed, turning Bluetooth off again");
4371         if (hci_stack->control && hci_stack->control->off){
4372             (*hci_stack->control->off)();
4373         }
4374         hci_emit_hci_open_failed();
4375         return err;
4376     }
4377 #endif
4378 
4379     return 0;
4380 }
4381 
4382 static void hci_power_enter_initializing_state(void){
4383     // set up state machine
4384     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
4385     hci_stack->hci_packet_buffer_reserved = false;
4386     hci_stack->state = HCI_STATE_INITIALIZING;
4387     hci_stack->substate = HCI_INIT_SEND_RESET;
4388 }
4389 
4390 static void hci_power_enter_halting_state(void){
4391 #ifdef ENABLE_BLE
4392     hci_whitelist_free();
4393 #endif
4394     // see hci_run
4395     hci_stack->state = HCI_STATE_HALTING;
4396     hci_stack->substate = HCI_HALTING_CLASSIC_STOP;
4397     // setup watchdog timer for disconnect - only triggers if Controller does not respond anymore
4398     btstack_run_loop_set_timer(&hci_stack->timeout, 1000);
4399     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4400     btstack_run_loop_add_timer(&hci_stack->timeout);
4401 }
4402 
4403 // returns error
4404 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
4405     int err;
4406     switch (power_mode){
4407         case HCI_POWER_ON:
4408             err = hci_power_control_on();
4409             if (err != 0) {
4410                 log_error("hci_power_control_on() error %d", err);
4411                 return err;
4412             }
4413             hci_power_enter_initializing_state();
4414             break;
4415         case HCI_POWER_OFF:
4416             // do nothing
4417             break;
4418         case HCI_POWER_SLEEP:
4419             // do nothing (with SLEEP == OFF)
4420             break;
4421         default:
4422             btstack_assert(false);
4423             break;
4424     }
4425     return ERROR_CODE_SUCCESS;
4426 }
4427 
4428 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
4429     switch (power_mode){
4430         case HCI_POWER_ON:
4431             // do nothing
4432             break;
4433         case HCI_POWER_OFF:
4434             // no connections yet, just turn it off
4435             hci_power_control_off();
4436             break;
4437         case HCI_POWER_SLEEP:
4438             // no connections yet, just turn it off
4439             hci_power_control_sleep();
4440             break;
4441         default:
4442             btstack_assert(false);
4443             break;
4444     }
4445     return ERROR_CODE_SUCCESS;
4446 }
4447 
4448 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
4449     switch (power_mode){
4450         case HCI_POWER_ON:
4451             // do nothing
4452             break;
4453         case HCI_POWER_OFF:
4454             hci_power_enter_halting_state();
4455             break;
4456         case HCI_POWER_SLEEP:
4457             // see hci_run
4458             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
4459             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
4460             break;
4461         default:
4462             btstack_assert(false);
4463             break;
4464     }
4465     return ERROR_CODE_SUCCESS;
4466 }
4467 
4468 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
4469     switch (power_mode){
4470         case HCI_POWER_ON:
4471             hci_power_enter_initializing_state();
4472             break;
4473         case HCI_POWER_OFF:
4474             // do nothing
4475             break;
4476         case HCI_POWER_SLEEP:
4477             // see hci_run
4478             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
4479             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
4480             break;
4481         default:
4482             btstack_assert(false);
4483             break;
4484     }
4485     return ERROR_CODE_SUCCESS;
4486 }
4487 
4488 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
4489     switch (power_mode){
4490         case HCI_POWER_ON:
4491             hci_power_enter_initializing_state();
4492             break;
4493         case HCI_POWER_OFF:
4494             hci_power_enter_halting_state();
4495             break;
4496         case HCI_POWER_SLEEP:
4497             // do nothing
4498             break;
4499         default:
4500             btstack_assert(false);
4501             break;
4502     }
4503     return ERROR_CODE_SUCCESS;
4504 }
4505 
4506 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4507     int err;
4508     switch (power_mode){
4509         case HCI_POWER_ON:
4510             err = hci_power_control_wake();
4511             if (err) return err;
4512             hci_power_enter_initializing_state();
4513             break;
4514         case HCI_POWER_OFF:
4515             hci_power_enter_halting_state();
4516             break;
4517         case HCI_POWER_SLEEP:
4518             // do nothing
4519             break;
4520         default:
4521             btstack_assert(false);
4522             break;
4523     }
4524     return ERROR_CODE_SUCCESS;
4525 }
4526 
4527 int hci_power_control(HCI_POWER_MODE power_mode){
4528     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4529     int err = 0;
4530     switch (hci_stack->state){
4531         case HCI_STATE_OFF:
4532             err = hci_power_control_state_off(power_mode);
4533             break;
4534         case HCI_STATE_INITIALIZING:
4535             err = hci_power_control_state_initializing(power_mode);
4536             break;
4537         case HCI_STATE_WORKING:
4538             err = hci_power_control_state_working(power_mode);
4539             break;
4540         case HCI_STATE_HALTING:
4541             err = hci_power_control_state_halting(power_mode);
4542             break;
4543         case HCI_STATE_FALLING_ASLEEP:
4544             err = hci_power_control_state_falling_asleep(power_mode);
4545             break;
4546         case HCI_STATE_SLEEPING:
4547             err = hci_power_control_state_sleeping(power_mode);
4548             break;
4549         default:
4550             btstack_assert(false);
4551             break;
4552     }
4553     if (err != 0){
4554         return err;
4555     }
4556 
4557     // create internal event
4558 	hci_emit_state();
4559 
4560 	// trigger next/first action
4561 	hci_run();
4562 
4563     return 0;
4564 }
4565 
4566 
4567 static void hci_halting_run(void) {
4568 
4569     log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4570 
4571     hci_connection_t *connection;
4572 #ifdef ENABLE_BLE
4573 #ifdef ENABLE_LE_PERIPHERAL
4574     bool stop_advertismenets;
4575 #endif
4576 #endif
4577 
4578     switch (hci_stack->substate) {
4579         case HCI_HALTING_CLASSIC_STOP:
4580 #ifdef ENABLE_CLASSIC
4581             if (!hci_can_send_command_packet_now()) return;
4582 
4583             if (hci_stack->connectable || hci_stack->discoverable){
4584                 hci_stack->substate = HCI_HALTING_LE_ADV_STOP;
4585                 hci_send_cmd(&hci_write_scan_enable, 0);
4586                 return;
4587             }
4588 #endif
4589             /* fall through */
4590 
4591         case HCI_HALTING_LE_ADV_STOP:
4592             hci_stack->substate = HCI_HALTING_LE_ADV_STOP;
4593 
4594 #ifdef ENABLE_BLE
4595 #ifdef ENABLE_LE_PERIPHERAL
4596             if (!hci_can_send_command_packet_now()) return;
4597 
4598             stop_advertismenets = (hci_stack->le_advertisements_state & LE_ADVERTISEMENT_STATE_ACTIVE) != 0;
4599 
4600 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
4601             if (hci_extended_advertising_supported()){
4602 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
4603                 btstack_linked_list_iterator_t it;
4604                 btstack_linked_list_iterator_init(&it, &hci_stack->le_advertising_sets);
4605                 // stop all periodic advertisements and check if an extended set is active
4606                 while (btstack_linked_list_iterator_has_next(&it)){
4607                     le_advertising_set_t * advertising_set = (le_advertising_set_t*) btstack_linked_list_iterator_next(&it);
4608                     if ((advertising_set->state & LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE) != 0) {
4609                         advertising_set->state &= ~LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE;
4610                         hci_send_cmd(&hci_le_set_periodic_advertising_enable, 0, advertising_set->advertising_handle);
4611                         return;
4612                     }
4613                     if ((advertising_set->state & LE_ADVERTISEMENT_STATE_ACTIVE) != 0) {
4614                         stop_advertismenets = true;
4615                         advertising_set->state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
4616                     }
4617                 }
4618 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
4619                 if (stop_advertismenets){
4620                     hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
4621                     hci_send_cmd(&hci_le_set_extended_advertising_enable, 0, 0, NULL, NULL, NULL);
4622                     return;
4623                 }
4624             }
4625             else
4626 #else
4627             {
4628                 if (stop_advertismenets) {
4629                     hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
4630                     hci_send_cmd(&hci_le_set_advertise_enable, 0);
4631                     return;
4632                 }
4633             }
4634 #endif  /* ENABLE_LE_EXTENDED_ADVERTISING*/
4635 #endif  /* ENABLE_LE_PERIPHERAL */
4636 #endif  /* ENABLE_BLE */
4637 
4638             /* fall through */
4639 
4640         case HCI_HALTING_LE_SCAN_STOP:
4641             hci_stack->substate = HCI_HALTING_LE_SCAN_STOP;
4642             if (!hci_can_send_command_packet_now()) return;
4643 
4644 #ifdef ENABLE_BLE
4645 #ifdef ENABLE_LE_CENTRAL
4646             if (hci_stack->le_scanning_active){
4647                 hci_le_scan_stop();
4648                 hci_stack->substate = HCI_HALTING_DISCONNECT_ALL;
4649                 return;
4650             }
4651 #endif
4652 #endif
4653 
4654             /* fall through */
4655 
4656         case HCI_HALTING_DISCONNECT_ALL:
4657             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL;
4658             if (!hci_can_send_command_packet_now()) return;
4659 
4660             // close all open connections
4661             connection = (hci_connection_t *) hci_stack->connections;
4662             if (connection) {
4663                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4664 
4665                 // check state
4666                 if (connection->state == SENT_DISCONNECT) return;
4667                 connection->state = SENT_DISCONNECT;
4668 
4669                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4670 
4671                 // finally, send the disconnect command
4672                 hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4673                 return;
4674             }
4675 
4676             btstack_run_loop_remove_timer(&hci_stack->timeout);
4677 
4678             hci_stack->substate = HCI_HALTING_READY_FOR_CLOSE;
4679 
4680             // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4681             log_info("HCI_STATE_HALTING: wait 50 ms");
4682             hci_stack->substate = HCI_HALTING_W4_CLOSE_TIMER;
4683             btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4684             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4685             btstack_run_loop_add_timer(&hci_stack->timeout);
4686             break;
4687 
4688         case HCI_HALTING_CLOSE:
4689             // close left over connections (that had not been properly closed before)
4690             hci_discard_connections();
4691 
4692             log_info("HCI_STATE_HALTING, calling off");
4693 
4694             // switch mode
4695             hci_power_control_off();
4696 
4697             log_info("HCI_STATE_HALTING, emitting state");
4698             hci_emit_state();
4699             log_info("HCI_STATE_HALTING, done");
4700             break;
4701 
4702         case HCI_HALTING_W4_CLOSE_TIMER:
4703             // keep waiting
4704 
4705             break;
4706         default:
4707             break;
4708     }
4709 };
4710 
4711 static void hci_falling_asleep_run(void){
4712     hci_connection_t * connection;
4713     switch(hci_stack->substate) {
4714         case HCI_FALLING_ASLEEP_DISCONNECT:
4715             log_info("HCI_STATE_FALLING_ASLEEP");
4716             // close all open connections
4717             connection =  (hci_connection_t *) hci_stack->connections;
4718             if (connection){
4719 
4720                 // send disconnect
4721                 if (!hci_can_send_command_packet_now()) return;
4722 
4723                 log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4724                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4725 
4726                 // send disconnected event right away - causes higher layer connections to get closed, too.
4727                 hci_shutdown_connection(connection);
4728                 return;
4729             }
4730 
4731             if (hci_classic_supported()){
4732                 // disable page and inquiry scan
4733                 if (!hci_can_send_command_packet_now()) return;
4734 
4735                 log_info("HCI_STATE_HALTING, disabling inq scans");
4736                 hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4737 
4738                 // continue in next sub state
4739                 hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4740                 break;
4741             }
4742 
4743             /* fall through */
4744 
4745             case HCI_FALLING_ASLEEP_COMPLETE:
4746                 log_info("HCI_STATE_HALTING, calling sleep");
4747                 // switch mode
4748                 hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4749                 hci_emit_state();
4750                 break;
4751 
4752                 default:
4753                     break;
4754     }
4755 }
4756 
4757 #ifdef ENABLE_CLASSIC
4758 
4759 static void hci_update_scan_enable(void){
4760     // 2 = page scan, 1 = inq scan
4761     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4762     hci_stack->gap_tasks_classic |= GAP_TASK_WRITE_SCAN_ENABLE;
4763     hci_run();
4764 }
4765 
4766 void gap_discoverable_control(uint8_t enable){
4767     if (enable) enable = 1; // normalize argument
4768 
4769     if (hci_stack->discoverable == enable){
4770         hci_emit_discoverable_enabled(hci_stack->discoverable);
4771         return;
4772     }
4773 
4774     hci_stack->discoverable = enable;
4775     hci_update_scan_enable();
4776 }
4777 
4778 void gap_connectable_control(uint8_t enable){
4779     if (enable) enable = 1; // normalize argument
4780 
4781     // don't emit event
4782     if (hci_stack->connectable == enable) return;
4783 
4784     hci_stack->connectable = enable;
4785     hci_update_scan_enable();
4786 }
4787 #endif
4788 
4789 void gap_local_bd_addr(bd_addr_t address_buffer){
4790     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4791 }
4792 
4793 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4794 static void hci_host_num_completed_packets(void){
4795 
4796     // create packet manually as arrays are not supported and num_commands should not get reduced
4797     hci_reserve_packet_buffer();
4798     uint8_t * packet = hci_get_outgoing_packet_buffer();
4799 
4800     uint16_t size = 0;
4801     uint16_t num_handles = 0;
4802     packet[size++] = 0x35;
4803     packet[size++] = 0x0c;
4804     size++;  // skip param len
4805     size++;  // skip num handles
4806 
4807     // add { handle, packets } entries
4808     btstack_linked_item_t * it;
4809     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4810         hci_connection_t * connection = (hci_connection_t *) it;
4811         if (connection->num_packets_completed){
4812             little_endian_store_16(packet, size, connection->con_handle);
4813             size += 2;
4814             little_endian_store_16(packet, size, connection->num_packets_completed);
4815             size += 2;
4816             //
4817             num_handles++;
4818             connection->num_packets_completed = 0;
4819         }
4820     }
4821 
4822     packet[2] = size - 3;
4823     packet[3] = num_handles;
4824 
4825     hci_stack->host_completed_packets = 0;
4826 
4827     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4828     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4829 
4830     // release packet buffer for synchronous transport implementations
4831     if (hci_transport_synchronous()){
4832         hci_release_packet_buffer();
4833         hci_emit_transport_packet_sent();
4834     }
4835 }
4836 #endif
4837 
4838 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4839     UNUSED(ds);
4840     hci_stack->substate = HCI_HALTING_CLOSE;
4841     // allow packet handlers to defer final shutdown
4842     hci_emit_state();
4843     hci_run();
4844 }
4845 
4846 static bool hci_run_acl_fragments(void){
4847     if (hci_stack->acl_fragmentation_total_size > 0u) {
4848         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4849         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4850         if (connection) {
4851             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4852                 hci_send_acl_packet_fragments(connection);
4853                 return true;
4854             }
4855         } else {
4856             // connection gone -> discard further fragments
4857             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4858             hci_stack->acl_fragmentation_total_size = 0;
4859             hci_stack->acl_fragmentation_pos = 0;
4860         }
4861     }
4862     return false;
4863 }
4864 
4865 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
4866 static bool hci_run_iso_fragments(void){
4867     if (hci_stack->iso_fragmentation_total_size > 0u) {
4868         // TODO: flow control
4869         if (hci_transport_can_send_prepared_packet_now(HCI_ISO_DATA_PACKET)){
4870             hci_send_iso_packet_fragments();
4871             return true;
4872         }
4873     }
4874     return false;
4875 }
4876 #endif
4877 
4878 #ifdef ENABLE_CLASSIC
4879 
4880 #ifdef ENABLE_HCI_SERIALIZED_CONTROLLER_OPERATIONS
4881 static bool hci_classic_operation_active(void) {
4882     if (hci_stack->inquiry_state >= GAP_INQUIRY_STATE_W4_ACTIVE){
4883         return true;
4884     }
4885     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
4886         return true;
4887     }
4888     btstack_linked_item_t * it;
4889     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next) {
4890         hci_connection_t *connection = (hci_connection_t *) it;
4891         switch (connection->state) {
4892             case SENT_CREATE_CONNECTION:
4893             case SENT_CANCEL_CONNECTION:
4894             case SENT_DISCONNECT:
4895                 return true;
4896             default:
4897                 break;
4898         }
4899     }
4900     return false;
4901 }
4902 #endif
4903 
4904 static bool hci_run_general_gap_classic(void){
4905 
4906     // assert stack is working and classic is active
4907     if (hci_classic_supported() == false)      return false;
4908     if (hci_stack->state != HCI_STATE_WORKING) return false;
4909 
4910     // decline incoming connections
4911     if (hci_stack->decline_reason){
4912         uint8_t reason = hci_stack->decline_reason;
4913         hci_stack->decline_reason = 0;
4914         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4915         return true;
4916     }
4917 
4918     if (hci_stack->gap_tasks_classic != 0){
4919         hci_run_gap_tasks_classic();
4920         return true;
4921     }
4922 
4923     // start/stop inquiry
4924     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4925 #ifdef ENABLE_HCI_SERIALIZED_CONTROLLER_OPERATIONS
4926         if (hci_classic_operation_active() == false)
4927 #endif
4928         {
4929             uint8_t duration = hci_stack->inquiry_state;
4930             hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4931             if (hci_stack->inquiry_max_period_length != 0){
4932                 hci_send_cmd(&hci_periodic_inquiry_mode, hci_stack->inquiry_max_period_length, hci_stack->inquiry_min_period_length, hci_stack->inquiry_lap, duration, 0);
4933             } else {
4934                 hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4935             }
4936             return true;
4937         }
4938     }
4939     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4940         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4941         hci_send_cmd(&hci_inquiry_cancel);
4942         return true;
4943     }
4944 
4945     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_EXIT_PERIODIC){
4946         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4947         hci_send_cmd(&hci_exit_periodic_inquiry_mode);
4948         return true;
4949     }
4950 
4951     // remote name request
4952     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4953 #ifdef ENABLE_HCI_SERIALIZED_CONTROLLER_OPERATIONS
4954         if (hci_classic_operation_active() == false)
4955 #endif
4956         {
4957             hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4958             hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4959                          hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4960             return true;
4961         }
4962     }
4963 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4964     // Local OOB data
4965     if (hci_stack->classic_read_local_oob_data){
4966         hci_stack->classic_read_local_oob_data = false;
4967         if (hci_command_supported(SUPPORTED_HCI_COMMAND_READ_LOCAL_OOB_EXTENDED_DATA_COMMAND)){
4968             hci_send_cmd(&hci_read_local_extended_oob_data);
4969         } else {
4970             hci_send_cmd(&hci_read_local_oob_data);
4971         }
4972     }
4973 #endif
4974     // pairing
4975     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4976         uint8_t state = hci_stack->gap_pairing_state;
4977         uint8_t pin_code[16];
4978         switch (state){
4979             case GAP_PAIRING_STATE_SEND_PIN:
4980                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4981                 memset(pin_code, 0, 16);
4982                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4983                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4984                 break;
4985             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4986                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4987                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4988                 break;
4989             case GAP_PAIRING_STATE_SEND_PASSKEY:
4990                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4991                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4992                 break;
4993             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4994                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4995                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4996                 break;
4997             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4998                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4999                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
5000                 break;
5001             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
5002                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
5003                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
5004                 break;
5005             default:
5006                 break;
5007         }
5008         return true;
5009     }
5010     return false;
5011 }
5012 #endif
5013 
5014 #ifdef ENABLE_BLE
5015 
5016 #ifdef ENABLE_LE_CENTRAL
5017 static void hci_le_scan_stop(void){
5018 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5019     if (hci_extended_advertising_supported()) {
5020             hci_send_cmd(&hci_le_set_extended_scan_enable, 0, 0, 0, 0);
5021         } else
5022 #endif
5023     {
5024         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
5025     }
5026 }
5027 #endif
5028 
5029 #ifdef ENABLE_LE_PERIPHERAL
5030 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5031 uint8_t hci_le_extended_advertising_operation_for_chunk(uint16_t pos, uint16_t len){
5032     uint8_t  operation = 0;
5033     if (pos == 0){
5034         // first fragment or complete data
5035         operation |= 1;
5036     }
5037     if (pos + LE_EXTENDED_ADVERTISING_MAX_CHUNK_LEN >= len){
5038         // last fragment or complete data
5039         operation |= 2;
5040     }
5041     return operation;
5042 }
5043 #endif
5044 #endif
5045 
5046 static bool hci_run_general_gap_le(void){
5047 
5048     btstack_linked_list_iterator_t lit;
5049 
5050     // Phase 1: collect what to stop
5051 
5052 #ifdef ENABLE_LE_CENTRAL
5053     bool scanning_stop = false;
5054     bool connecting_stop = false;
5055 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5056 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5057     bool periodic_sync_stop = false;
5058 #endif
5059 #endif
5060 #endif
5061 
5062 #ifdef ENABLE_LE_PERIPHERAL
5063     bool advertising_stop = false;
5064 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5065     le_advertising_set_t * advertising_stop_set = NULL;
5066 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5067     bool periodic_advertising_stop = false;
5068 #endif
5069 #endif
5070 #endif
5071 
5072     // check if own address changes
5073     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
5074 
5075     // check if whitelist needs modification
5076     bool whitelist_modification_pending = false;
5077     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5078     while (btstack_linked_list_iterator_has_next(&lit)){
5079         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5080         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
5081             whitelist_modification_pending = true;
5082             break;
5083         }
5084     }
5085 
5086     // check if resolving list needs modification
5087     bool resolving_list_modification_pending = false;
5088 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
5089     bool resolving_list_supported = hci_command_supported(SUPPORTED_HCI_COMMAND_LE_SET_ADDRESS_RESOLUTION_ENABLE);
5090 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
5091         resolving_list_modification_pending = true;
5092     }
5093 #endif
5094 
5095 #ifdef ENABLE_LE_CENTRAL
5096 
5097 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5098     // check if periodic advertiser list needs modification
5099     bool periodic_list_modification_pending = false;
5100     btstack_linked_list_iterator_init(&lit, &hci_stack->le_periodic_advertiser_list);
5101     while (btstack_linked_list_iterator_has_next(&lit)){
5102         periodic_advertiser_list_entry_t * entry = (periodic_advertiser_list_entry_t*) btstack_linked_list_iterator_next(&lit);
5103         if (entry->state & (LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER | LE_PERIODIC_ADVERTISER_LIST_ENTRY_REMOVE_FROM_CONTROLLER)){
5104             periodic_list_modification_pending = true;
5105             break;
5106         }
5107     }
5108 #endif
5109 
5110     // scanning control
5111     if (hci_stack->le_scanning_active) {
5112         // stop if:
5113         // - parameter change required
5114         // - it's disabled
5115         // - whitelist change required but used for scanning
5116         // - resolving list modified
5117         // - own address changes
5118         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
5119         if ((hci_stack->le_scanning_param_update) ||
5120             !hci_stack->le_scanning_enabled ||
5121             (scanning_uses_whitelist && whitelist_modification_pending) ||
5122             resolving_list_modification_pending ||
5123             random_address_change){
5124 
5125             scanning_stop = true;
5126         }
5127     }
5128 
5129     // connecting control
5130     bool connecting_with_whitelist;
5131     switch (hci_stack->le_connecting_state){
5132         case LE_CONNECTING_DIRECT:
5133         case LE_CONNECTING_WHITELIST:
5134             // stop connecting if:
5135             // - connecting uses white and whitelist modification pending
5136             // - if it got disabled
5137             // - resolving list modified
5138             // - own address changes
5139             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
5140             if ((connecting_with_whitelist && whitelist_modification_pending) ||
5141                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
5142                 resolving_list_modification_pending ||
5143                 random_address_change) {
5144 
5145                 connecting_stop = true;
5146             }
5147             break;
5148         default:
5149             break;
5150     }
5151 
5152 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5153 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5154     // periodic sync control
5155     bool sync_with_advertiser_list;
5156     switch(hci_stack->le_periodic_sync_state){
5157         case LE_CONNECTING_DIRECT:
5158         case LE_CONNECTING_WHITELIST:
5159             // stop sync if:
5160             // - sync with advertiser list and advertiser list modification pending
5161             // - if it got disabled
5162             sync_with_advertiser_list = hci_stack->le_periodic_sync_state == LE_CONNECTING_WHITELIST;
5163             if ((sync_with_advertiser_list && periodic_list_modification_pending) ||
5164                     (hci_stack->le_periodic_sync_request == LE_CONNECTING_IDLE)){
5165                 periodic_sync_stop = true;
5166             }
5167             break;
5168         default:
5169             break;
5170     }
5171 #endif
5172 #endif
5173 
5174 #endif /* ENABLE_LE_CENTRAL */
5175 
5176 #ifdef ENABLE_LE_PERIPHERAL
5177     // le advertisement control
5178     if ((hci_stack->le_advertisements_state & LE_ADVERTISEMENT_STATE_ACTIVE) != 0){
5179         // stop if:
5180         // - parameter change required
5181         // - random address used in advertising and changes
5182         // - it's disabled
5183         // - whitelist change required but used for advertisement filter policy
5184         // - resolving list modified
5185         // - own address changes
5186         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
5187         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
5188         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
5189         if (advertising_change ||
5190             (advertising_uses_random_address && random_address_change) ||
5191             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
5192             (advertising_uses_whitelist && whitelist_modification_pending) ||
5193             resolving_list_modification_pending ||
5194             random_address_change) {
5195 
5196             advertising_stop = true;
5197         }
5198     }
5199 
5200 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5201     if (hci_extended_advertising_supported() && (advertising_stop == false)){
5202         btstack_linked_list_iterator_t it;
5203         btstack_linked_list_iterator_init(&it, &hci_stack->le_advertising_sets);
5204         while (btstack_linked_list_iterator_has_next(&it)){
5205             le_advertising_set_t * advertising_set = (le_advertising_set_t*) btstack_linked_list_iterator_next(&it);
5206             if ((advertising_set->state & LE_ADVERTISEMENT_STATE_ACTIVE) != 0) {
5207                 // stop if:
5208                 // - parameter change required
5209                 // - random address used in connectable advertising and changes
5210                 // - it's disabled
5211                 // - whitelist change required but used for advertisement filter policy
5212                 // - resolving list modified
5213                 // - own address changes
5214                 // - advertisement set will be removed
5215                 bool advertising_uses_whitelist = advertising_set->extended_params.advertising_filter_policy != 0;
5216                 bool advertising_connectable = (advertising_set->extended_params.advertising_event_properties & 1) != 0;
5217                 bool advertising_uses_random_address =
5218                         (advertising_set->extended_params.own_address_type != BD_ADDR_TYPE_LE_PUBLIC) &&
5219                         advertising_connectable;
5220                 bool advertising_parameter_change = (advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
5221                 bool advertising_enabled = (advertising_set->state & LE_ADVERTISEMENT_STATE_ENABLED) != 0;
5222                 bool advertising_set_random_address_change =
5223                         (advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
5224                 bool advertising_set_will_be_removed =
5225                         (advertising_set->state & LE_ADVERTISEMENT_TASKS_REMOVE_SET) != 0;
5226                 if (advertising_parameter_change ||
5227                     (advertising_uses_random_address && advertising_set_random_address_change) ||
5228                     (advertising_enabled == false) ||
5229                     (advertising_uses_whitelist && whitelist_modification_pending) ||
5230                     resolving_list_modification_pending ||
5231                     advertising_set_will_be_removed) {
5232 
5233                     advertising_stop = true;
5234                     advertising_stop_set = advertising_set;
5235                     break;
5236                 }
5237             }
5238 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5239             if ((advertising_set->state & LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE) != 0) {
5240                 // stop if:
5241                 // - it's disabled
5242                 // - parameter change required
5243                 bool periodic_enabled = (advertising_set->state & LE_ADVERTISEMENT_STATE_PERIODIC_ENABLED) != 0;
5244                 bool periodic_parameter_change = (advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_PERIODIC_PARAMS) != 0;
5245                 if ((periodic_enabled == false) || periodic_parameter_change){
5246                     periodic_advertising_stop = true;
5247                     advertising_stop_set = advertising_set;
5248                 }
5249             }
5250 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
5251         }
5252     }
5253 #endif
5254 
5255 #endif
5256 
5257 
5258     // Phase 2: stop everything that should be off during modifications
5259 
5260 #ifdef ENABLE_LE_CENTRAL
5261     if (scanning_stop){
5262         hci_stack->le_scanning_active = false;
5263         hci_le_scan_stop();
5264         return true;
5265     }
5266 
5267     if (connecting_stop){
5268         hci_send_cmd(&hci_le_create_connection_cancel);
5269         return true;
5270     }
5271 
5272 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5273     if (hci_stack->le_periodic_terminate_sync_handle != HCI_CON_HANDLE_INVALID){
5274         uint16_t sync_handle = hci_stack->le_periodic_terminate_sync_handle;
5275         hci_stack->le_periodic_terminate_sync_handle = HCI_CON_HANDLE_INVALID;
5276         hci_send_cmd(&hci_le_periodic_advertising_terminate_sync, sync_handle);
5277         return true;
5278     }
5279 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5280     if (periodic_sync_stop){
5281         hci_stack->le_periodic_sync_state = LE_CONNECTING_CANCEL;
5282         hci_send_cmd(&hci_le_periodic_advertising_create_sync_cancel);
5283         return true;
5284     }
5285 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
5286 #endif
5287 #endif
5288 
5289 #ifdef ENABLE_LE_PERIPHERAL
5290     if (advertising_stop){
5291 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5292         if (hci_extended_advertising_supported()) {
5293             uint8_t advertising_stop_handle;
5294             if (advertising_stop_set != NULL){
5295                 advertising_stop_handle = advertising_stop_set->advertising_handle;
5296                 advertising_stop_set->state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
5297             } else {
5298                 advertising_stop_handle = 0;
5299                 hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
5300             }
5301             const uint8_t advertising_handles[] = { advertising_stop_handle };
5302             const uint16_t durations[] = { 0 };
5303             const uint16_t max_events[] = { 0 };
5304             hci_send_cmd(&hci_le_set_extended_advertising_enable, 0, 1, advertising_handles, durations, max_events);
5305         } else
5306 #endif
5307         {
5308             hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ACTIVE;
5309             hci_send_cmd(&hci_le_set_advertise_enable, 0);
5310         }
5311         return true;
5312     }
5313 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5314 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5315     if (periodic_advertising_stop){
5316         advertising_stop_set->state &= ~LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE;
5317         hci_send_cmd(&hci_le_set_periodic_advertising_enable, 0, advertising_stop_set->advertising_handle);
5318         return true;
5319     }
5320 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
5321 #endif /* ENABLE_LE_EXTENDED_ADVERTISING */
5322 #endif
5323 
5324     // Phase 3: modify
5325 
5326     if (random_address_change){
5327         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
5328 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5329         if (hci_extended_advertising_supported()) {
5330             hci_send_cmd(&hci_le_set_advertising_set_random_address, 0, hci_stack->le_random_address);
5331         }
5332 #endif
5333         {
5334             hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
5335         }
5336         return true;
5337     }
5338 
5339 #ifdef ENABLE_LE_CENTRAL
5340     if (hci_stack->le_scanning_param_update){
5341         hci_stack->le_scanning_param_update = false;
5342 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5343         if (hci_extended_advertising_supported()){
5344             // prepare arrays for all PHYs
5345             uint8_t  scan_types[1]     = { hci_stack->le_scan_type     };
5346             uint16_t scan_intervals[1] = { hci_stack->le_scan_interval };
5347             uint16_t scan_windows[1]   =    { hci_stack->le_scan_window   };
5348             uint8_t  scanning_phys     = 1;  // LE 1M PHY
5349             hci_send_cmd(&hci_le_set_extended_scan_parameters, hci_stack->le_own_addr_type,
5350                          hci_stack->le_scan_filter_policy, scanning_phys, scan_types, scan_intervals, scan_windows);
5351         } else
5352 #endif
5353         {
5354             hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
5355                          hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
5356         }
5357         return true;
5358     }
5359 #endif
5360 
5361 #ifdef ENABLE_LE_PERIPHERAL
5362     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
5363         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5364         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
5365 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5366         if (hci_extended_advertising_supported()){
5367             // map advertisment type to advertising event properties
5368             uint16_t adv_event_properties = 0;
5369             const uint16_t mapping[] = { 0b00010011, 0b00010101, 0b00011101, 0b00010010, 0b00010000};
5370             if (hci_stack->le_advertisements_type < (sizeof(mapping)/sizeof(uint16_t))){
5371                 adv_event_properties = mapping[hci_stack->le_advertisements_type];
5372             }
5373             hci_stack->le_advertising_set_in_current_command = 0;
5374             hci_send_cmd(&hci_le_set_extended_advertising_parameters,
5375                          0,
5376                          adv_event_properties,
5377                          hci_stack->le_advertisements_interval_min,
5378                          hci_stack->le_advertisements_interval_max,
5379                          hci_stack->le_advertisements_channel_map,
5380                          hci_stack->le_advertisements_own_addr_type,
5381                          hci_stack->le_advertisements_direct_address_type,
5382                          hci_stack->le_advertisements_direct_address,
5383                          hci_stack->le_advertisements_filter_policy,
5384                          0x7f,  // tx power: no preference
5385                          0x01,  // primary adv phy: LE 1M
5386                          0,     // secondary adv max skip
5387                          0,     // secondary adv phy
5388                          0,     // adv sid
5389                          0      // scan request notification
5390                          );
5391         }
5392 #endif
5393         {
5394             hci_send_cmd(&hci_le_set_advertising_parameters,
5395                          hci_stack->le_advertisements_interval_min,
5396                          hci_stack->le_advertisements_interval_max,
5397                          hci_stack->le_advertisements_type,
5398                          hci_stack->le_advertisements_own_addr_type,
5399                          hci_stack->le_advertisements_direct_address_type,
5400                          hci_stack->le_advertisements_direct_address,
5401                          hci_stack->le_advertisements_channel_map,
5402                          hci_stack->le_advertisements_filter_policy);
5403         }
5404         return true;
5405     }
5406 
5407     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
5408         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5409         uint8_t adv_data_clean[31];
5410         memset(adv_data_clean, 0, sizeof(adv_data_clean));
5411         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
5412                      hci_stack->le_advertisements_data_len);
5413         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
5414 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5415         if (hci_extended_advertising_supported()){
5416             hci_stack->le_advertising_set_in_current_command = 0;
5417             hci_send_cmd(&hci_le_set_extended_advertising_data, 0, 0x03, 0x01, hci_stack->le_advertisements_data_len, adv_data_clean);
5418         } else
5419 #endif
5420         {
5421             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
5422         }
5423         return true;
5424     }
5425 
5426     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
5427         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5428         uint8_t scan_data_clean[31];
5429         memset(scan_data_clean, 0, sizeof(scan_data_clean));
5430         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
5431                      hci_stack->le_scan_response_data_len);
5432         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
5433 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5434         if (hci_extended_advertising_supported()){
5435             hci_stack->le_advertising_set_in_current_command = 0;
5436             hci_send_cmd(&hci_le_set_extended_scan_response_data, 0, 0x03, 0x01, hci_stack->le_scan_response_data_len, scan_data_clean);
5437         } else
5438 #endif
5439         {
5440             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
5441         }
5442         return true;
5443     }
5444 
5445 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5446     if (hci_extended_advertising_supported()) {
5447         btstack_linked_list_iterator_t it;
5448         btstack_linked_list_iterator_init(&it, &hci_stack->le_advertising_sets);
5449         while (btstack_linked_list_iterator_has_next(&it)){
5450             le_advertising_set_t * advertising_set = (le_advertising_set_t*) btstack_linked_list_iterator_next(&it);
5451             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_REMOVE_SET) != 0) {
5452                 advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_REMOVE_SET;
5453                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5454                 hci_send_cmd(&hci_le_remove_advertising_set, advertising_set->advertising_handle);
5455                 return true;
5456             }
5457             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0){
5458                 advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
5459                 hci_send_cmd(&hci_le_set_advertising_set_random_address, advertising_set->advertising_handle, advertising_set->random_address);
5460                 return true;
5461             }
5462             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0){
5463                 advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5464                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5465                 hci_send_cmd(&hci_le_set_extended_advertising_parameters,
5466                              advertising_set->advertising_handle,
5467                              advertising_set->extended_params.advertising_event_properties,
5468                              advertising_set->extended_params.primary_advertising_interval_min,
5469                              advertising_set->extended_params.primary_advertising_interval_max,
5470                              advertising_set->extended_params.primary_advertising_channel_map,
5471                              advertising_set->extended_params.own_address_type,
5472                              advertising_set->extended_params.peer_address_type,
5473                              advertising_set->extended_params.peer_address,
5474                              advertising_set->extended_params.advertising_filter_policy,
5475                              advertising_set->extended_params.advertising_tx_power,
5476                              advertising_set->extended_params.primary_advertising_phy,
5477                              advertising_set->extended_params.secondary_advertising_max_skip,
5478                              advertising_set->extended_params.secondary_advertising_phy,
5479                              advertising_set->extended_params.advertising_sid,
5480                              advertising_set->extended_params.scan_request_notification_enable
5481                 );
5482                 return true;
5483             }
5484             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA) != 0) {
5485                 uint16_t pos = advertising_set->adv_data_pos;
5486                 uint8_t  operation = hci_le_extended_advertising_operation_for_chunk(pos, advertising_set->adv_data_len);
5487                 uint16_t data_to_upload = btstack_min(advertising_set->adv_data_len - pos, LE_EXTENDED_ADVERTISING_MAX_CHUNK_LEN);
5488                 if ((operation & 0x02) != 0){
5489                     // last fragment or complete data
5490                     operation |= 2;
5491                     advertising_set->adv_data_pos = 0;
5492                     advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5493                 } else {
5494                     advertising_set->adv_data_pos += data_to_upload;
5495                 }
5496                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5497                 hci_send_cmd(&hci_le_set_extended_advertising_data, advertising_set->advertising_handle, operation, 0x01, data_to_upload, &advertising_set->adv_data[pos]);
5498                 return true;
5499             }
5500             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA) != 0) {
5501                 uint16_t pos = advertising_set->scan_data_pos;
5502                 uint8_t  operation = hci_le_extended_advertising_operation_for_chunk(pos, advertising_set->scan_data_len);
5503                 uint16_t data_to_upload = btstack_min(advertising_set->scan_data_len - pos, LE_EXTENDED_ADVERTISING_MAX_CHUNK_LEN);
5504                 if ((operation & 0x02) != 0){
5505                     advertising_set->scan_data_pos = 0;
5506                     advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5507                 } else {
5508                     advertising_set->scan_data_pos += data_to_upload;
5509                 }
5510                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5511                 hci_send_cmd(&hci_le_set_extended_scan_response_data, operation, 0x03, 0x01, data_to_upload, &advertising_set->scan_data[pos]);
5512                 return true;
5513             }
5514 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5515             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_PERIODIC_PARAMS) != 0){
5516                 advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_PERIODIC_PARAMS;
5517                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5518                 hci_send_cmd(&hci_le_set_periodic_advertising_parameters,
5519                              advertising_set->advertising_handle,
5520                              advertising_set->periodic_params.periodic_advertising_interval_min,
5521                              advertising_set->periodic_params.periodic_advertising_interval_max,
5522                              advertising_set->periodic_params.periodic_advertising_properties);
5523                 return true;
5524             }
5525             if ((advertising_set->tasks & LE_ADVERTISEMENT_TASKS_SET_PERIODIC_DATA) != 0) {
5526                 uint16_t pos = advertising_set->periodic_data_pos;
5527                 uint8_t  operation = hci_le_extended_advertising_operation_for_chunk(pos, advertising_set->periodic_data_len);
5528                 uint16_t data_to_upload = btstack_min(advertising_set->periodic_data_len - pos, LE_EXTENDED_ADVERTISING_MAX_CHUNK_LEN);
5529                 if ((operation & 0x02) != 0){
5530                     // last fragment or complete data
5531                     operation |= 2;
5532                     advertising_set->periodic_data_pos = 0;
5533                     advertising_set->tasks &= ~LE_ADVERTISEMENT_TASKS_SET_PERIODIC_DATA;
5534                 } else {
5535                     advertising_set->periodic_data_pos += data_to_upload;
5536                 }
5537                 hci_stack->le_advertising_set_in_current_command = advertising_set->advertising_handle;
5538                 hci_send_cmd(&hci_le_set_periodic_advertising_data, advertising_set->advertising_handle, operation, data_to_upload, &advertising_set->periodic_data[pos]);
5539                 return true;
5540             }
5541 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
5542         }
5543     }
5544 #endif
5545 
5546 #endif
5547 
5548 #ifdef ENABLE_LE_CENTRAL
5549     // if connect with whitelist was active and is not cancelled yet, wait until next time
5550     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
5551 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5552     // if periodic sync with advertiser list was active and is not cancelled yet, wait until next time
5553     if (hci_stack->le_periodic_sync_state == LE_CONNECTING_CANCEL) return false;
5554 #endif
5555 #endif
5556 
5557     // LE Whitelist Management
5558     if (whitelist_modification_pending){
5559         // add/remove entries
5560         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5561         while (btstack_linked_list_iterator_has_next(&lit)){
5562             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5563 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
5564 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5565 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
5566 				return true;
5567 			}
5568             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
5569 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
5570                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
5571                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
5572                 return true;
5573             }
5574             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
5575 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5576 				btstack_memory_whitelist_entry_free(entry);
5577             }
5578         }
5579     }
5580 
5581 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
5582     // LE Resolving List Management
5583     if (resolving_list_supported) {
5584 		uint16_t i;
5585 		switch (hci_stack->le_resolving_list_state) {
5586 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
5587 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
5588 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
5589 				return true;
5590 			case LE_RESOLVING_LIST_READ_SIZE:
5591 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
5592 				hci_send_cmd(&hci_le_read_resolving_list_size);
5593 				return true;
5594 			case LE_RESOLVING_LIST_SEND_CLEAR:
5595 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
5596 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
5597 							  sizeof(hci_stack->le_resolving_list_add_entries));
5598 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
5599 							  sizeof(hci_stack->le_resolving_list_remove_entries));
5600 				hci_send_cmd(&hci_le_clear_resolving_list);
5601 				return true;
5602 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
5603 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
5604 					uint8_t offset = i >> 3;
5605 					uint8_t mask = 1 << (i & 7);
5606 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
5607 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
5608 					bd_addr_t peer_identity_addreses;
5609 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
5610 					sm_key_t peer_irk;
5611 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
5612 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
5613 
5614 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
5615 					// trigger whitelist entry 'update' (work around for controller bug)
5616 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5617 					while (btstack_linked_list_iterator_has_next(&lit)) {
5618 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
5619 						if (entry->address_type != peer_identity_addr_type) continue;
5620 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
5621 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
5622 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
5623 					}
5624 #endif
5625 
5626 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
5627 								 peer_identity_addreses);
5628 					return true;
5629 				}
5630 
5631 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
5632 
5633 				/* fall through */
5634 
5635 			case LE_RESOLVING_LIST_ADD_ENTRIES:
5636 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
5637 					uint8_t offset = i >> 3;
5638 					uint8_t mask = 1 << (i & 7);
5639 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
5640 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
5641 					bd_addr_t peer_identity_addreses;
5642 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
5643 					sm_key_t peer_irk;
5644 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
5645 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
5646 					const uint8_t *local_irk = gap_get_persistent_irk();
5647 					// command uses format specifier 'P' that stores 16-byte value without flip
5648 					uint8_t local_irk_flipped[16];
5649 					uint8_t peer_irk_flipped[16];
5650 					reverse_128(local_irk, local_irk_flipped);
5651 					reverse_128(peer_irk, peer_irk_flipped);
5652 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
5653 								 peer_irk_flipped, local_irk_flipped);
5654 					return true;
5655 				}
5656 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
5657 				break;
5658 
5659 			default:
5660 				break;
5661 		}
5662 	}
5663     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
5664 #endif
5665 
5666 #ifdef ENABLE_LE_CENTRAL
5667 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5668     // LE Whitelist Management
5669     if (periodic_list_modification_pending){
5670         // add/remove entries
5671         btstack_linked_list_iterator_init(&lit, &hci_stack->le_periodic_advertiser_list);
5672         while (btstack_linked_list_iterator_has_next(&lit)){
5673             periodic_advertiser_list_entry_t * entry = (periodic_advertiser_list_entry_t*) btstack_linked_list_iterator_next(&lit);
5674             if (entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_REMOVE_FROM_CONTROLLER){
5675                 entry->state &= ~LE_PERIODIC_ADVERTISER_LIST_ENTRY_REMOVE_FROM_CONTROLLER;
5676                 hci_send_cmd(&hci_le_remove_device_from_periodic_advertiser_list, entry->address_type, entry->address);
5677                 return true;
5678             }
5679             if (entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER){
5680                 entry->state &= ~LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER;
5681                 entry->state |= LE_PERIODIC_ADVERTISER_LIST_ENTRY_ON_CONTROLLER;
5682                 hci_send_cmd(&hci_le_add_device_to_periodic_advertiser_list, entry->address_type, entry->address);
5683                 return true;
5684             }
5685             if ((entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_ON_CONTROLLER) == 0){
5686                 btstack_linked_list_remove(&hci_stack->le_periodic_advertiser_list, (btstack_linked_item_t *) entry);
5687                 btstack_memory_periodic_advertiser_list_entry_free(entry);
5688             }
5689         }
5690     }
5691 #endif
5692 #endif
5693 
5694     // post-pone all actions until stack is fully working
5695     if (hci_stack->state != HCI_STATE_WORKING) return false;
5696 
5697     // advertisements, active scanning, and creating connections requires random address to be set if using private address
5698     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
5699 
5700     // Phase 4: restore state
5701 
5702 #ifdef ENABLE_LE_CENTRAL
5703     // re-start scanning
5704     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
5705         hci_stack->le_scanning_active = true;
5706 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5707         if (hci_extended_advertising_supported()){
5708             hci_send_cmd(&hci_le_set_extended_scan_enable, 1, 0, 0, 0);
5709         } else
5710 #endif
5711         {
5712             hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
5713         }
5714         return true;
5715     }
5716 #endif
5717 
5718 #ifdef ENABLE_LE_CENTRAL
5719     // re-start connecting
5720     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
5721         bd_addr_t null_addr;
5722         memset(null_addr, 0, 6);
5723         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
5724         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
5725         hci_send_cmd(&hci_le_create_connection,
5726                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
5727                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
5728                      1,         // use whitelist
5729                      0,         // peer address type
5730                      null_addr, // peer bd addr
5731                      hci_stack->le_connection_own_addr_type,   // our addr type:
5732                      hci_stack->le_connection_interval_min,    // conn interval min
5733                      hci_stack->le_connection_interval_max,    // conn interval max
5734                      hci_stack->le_connection_latency,         // conn latency
5735                      hci_stack->le_supervision_timeout,        // conn latency
5736                      hci_stack->le_minimum_ce_length,          // min ce length
5737                      hci_stack->le_maximum_ce_length           // max ce length
5738         );
5739         return true;
5740     }
5741 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5742     if (hci_stack->le_periodic_sync_state == LE_CONNECTING_IDLE){
5743         switch(hci_stack->le_periodic_sync_request){
5744             case LE_CONNECTING_DIRECT:
5745             case LE_CONNECTING_WHITELIST:
5746                 hci_stack->le_periodic_sync_state = ((hci_stack->le_periodic_sync_options & 1) != 0) ? LE_CONNECTING_WHITELIST : LE_CONNECTING_DIRECT;
5747                 hci_send_cmd(&hci_le_periodic_advertising_create_sync,
5748                              hci_stack->le_periodic_sync_options,
5749                              hci_stack->le_periodic_sync_advertising_sid,
5750                              hci_stack->le_periodic_sync_advertiser_address_type,
5751                              hci_stack->le_periodic_sync_advertiser_address,
5752                              hci_stack->le_periodic_sync_skip,
5753                              hci_stack->le_periodic_sync_timeout,
5754                              hci_stack->le_periodic_sync_cte_type);
5755                 return true;
5756             default:
5757                 break;
5758         }
5759     }
5760 #endif
5761 #endif
5762 
5763 #ifdef ENABLE_LE_PERIPHERAL
5764     // re-start advertising
5765     if (hci_stack->le_advertisements_enabled_for_current_roles && ((hci_stack->le_advertisements_state & LE_ADVERTISEMENT_STATE_ACTIVE) == 0)){
5766         // check if advertisements should be enabled given
5767         hci_stack->le_advertisements_state |= LE_ADVERTISEMENT_STATE_ACTIVE;
5768         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
5769 
5770 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5771         if (hci_extended_advertising_supported()){
5772             const uint8_t advertising_handles[] = { 0 };
5773             const uint16_t durations[] = { 0 };
5774             const uint16_t max_events[] = { 0 };
5775             hci_send_cmd(&hci_le_set_extended_advertising_enable, 1, 1, advertising_handles, durations, max_events);
5776         } else
5777 #endif
5778         {
5779             hci_send_cmd(&hci_le_set_advertise_enable, 1);
5780         }
5781         return true;
5782     }
5783 
5784 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5785     if (hci_extended_advertising_supported()) {
5786         btstack_linked_list_iterator_t it;
5787         btstack_linked_list_iterator_init(&it, &hci_stack->le_advertising_sets);
5788         while (btstack_linked_list_iterator_has_next(&it)) {
5789             le_advertising_set_t *advertising_set = (le_advertising_set_t *) btstack_linked_list_iterator_next(&it);
5790             if (((advertising_set->state & LE_ADVERTISEMENT_STATE_ENABLED) != 0) && ((advertising_set->state & LE_ADVERTISEMENT_STATE_ACTIVE) == 0)){
5791                 advertising_set->state |= LE_ADVERTISEMENT_STATE_ACTIVE;
5792                 const uint8_t advertising_handles[] = { advertising_set->advertising_handle };
5793                 const uint16_t durations[] = { advertising_set->enable_timeout };
5794                 const uint16_t max_events[] = { advertising_set->enable_max_scan_events };
5795                 hci_send_cmd(&hci_le_set_extended_advertising_enable, 1, 1, advertising_handles, durations, max_events);
5796                 return true;
5797             }
5798 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
5799             if (((advertising_set->state & LE_ADVERTISEMENT_STATE_PERIODIC_ENABLED) != 0) && ((advertising_set->state & LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE) == 0)){
5800                 advertising_set->state |= LE_ADVERTISEMENT_STATE_PERIODIC_ACTIVE;
5801                 uint8_t enable = 1;
5802                 if (advertising_set->periodic_include_adi){
5803                     enable |= 2;
5804                 }
5805                 hci_send_cmd(&hci_le_set_periodic_advertising_enable, enable, advertising_set->advertising_handle);
5806                 return true;
5807             }
5808 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
5809         }
5810     }
5811 #endif
5812 #endif
5813 
5814     return false;
5815 }
5816 #endif
5817 
5818 static bool hci_run_general_pending_commands(void){
5819     btstack_linked_item_t * it;
5820     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5821         hci_connection_t * connection = (hci_connection_t *) it;
5822 
5823         switch(connection->state){
5824             case SEND_CREATE_CONNECTION:
5825                 switch(connection->address_type){
5826 #ifdef ENABLE_CLASSIC
5827                     case BD_ADDR_TYPE_ACL:
5828                         log_info("sending hci_create_connection");
5829                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
5830                         break;
5831 #endif
5832                     default:
5833 #ifdef ENABLE_BLE
5834 #ifdef ENABLE_LE_CENTRAL
5835                         log_info("sending hci_le_create_connection");
5836                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
5837                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
5838 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
5839                         if (hci_extended_advertising_supported()) {
5840                             uint16_t le_connection_scan_interval[1] = { hci_stack->le_connection_scan_interval };
5841                             uint16_t le_connection_scan_window[1]   = { hci_stack->le_connection_scan_window };
5842                             uint16_t le_connection_interval_min[1]  = { hci_stack->le_connection_interval_min };
5843                             uint16_t le_connection_interval_max[1]  = { hci_stack->le_connection_interval_max };
5844                             uint16_t le_connection_latency[1]       = { hci_stack->le_connection_latency };
5845                             uint16_t le_supervision_timeout[1]      = { hci_stack->le_supervision_timeout };
5846                             uint16_t le_minimum_ce_length[1]        = { hci_stack->le_minimum_ce_length };
5847                             uint16_t le_maximum_ce_length[1]        = { hci_stack->le_maximum_ce_length };
5848                             hci_send_cmd(&hci_le_extended_create_connection,
5849                                          0,         // don't use whitelist
5850                                          hci_stack->le_connection_own_addr_type,   // our addr type:
5851                                          connection->address_type,      // peer address type
5852                                          connection->address,           // peer bd addr
5853                                          1,                             // initiating PHY - 1M
5854                                          le_connection_scan_interval,   // conn scan interval
5855                                          le_connection_scan_window,     // conn scan windows
5856                                          le_connection_interval_min,    // conn interval min
5857                                          le_connection_interval_max,    // conn interval max
5858                                          le_connection_latency,         // conn latency
5859                                          le_supervision_timeout,        // conn latency
5860                                          le_minimum_ce_length,          // min ce length
5861                                          le_maximum_ce_length           // max ce length
5862                             );                        }
5863                         else
5864 #endif
5865                         {
5866                             hci_send_cmd(&hci_le_create_connection,
5867                                          hci_stack->le_connection_scan_interval,    // conn scan interval
5868                                          hci_stack->le_connection_scan_window,      // conn scan windows
5869                                          0,         // don't use whitelist
5870                                          connection->address_type, // peer address type
5871                                          connection->address,      // peer bd addr
5872                                          hci_stack->le_connection_own_addr_type,   // our addr type:
5873                                          hci_stack->le_connection_interval_min,    // conn interval min
5874                                          hci_stack->le_connection_interval_max,    // conn interval max
5875                                          hci_stack->le_connection_latency,         // conn latency
5876                                          hci_stack->le_supervision_timeout,        // conn latency
5877                                          hci_stack->le_minimum_ce_length,          // min ce length
5878                                          hci_stack->le_maximum_ce_length          // max ce length
5879                             );
5880                         }
5881                         connection->state = SENT_CREATE_CONNECTION;
5882 #endif
5883 #endif
5884                         break;
5885                 }
5886                 return true;
5887 
5888 #ifdef ENABLE_CLASSIC
5889             case RECEIVED_CONNECTION_REQUEST:
5890                 connection->role  = HCI_ROLE_SLAVE;
5891                 if (connection->address_type == BD_ADDR_TYPE_ACL){
5892                     log_info("sending hci_accept_connection_request");
5893                     connection->state = ACCEPTED_CONNECTION_REQUEST;
5894                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
5895                     return true;
5896                 }
5897                 break;
5898 #endif
5899 
5900 #ifdef ENABLE_BLE
5901 #ifdef ENABLE_LE_CENTRAL
5902             case SEND_CANCEL_CONNECTION:
5903                 connection->state = SENT_CANCEL_CONNECTION;
5904                 hci_send_cmd(&hci_le_create_connection_cancel);
5905                 return true;
5906 #endif
5907 #endif
5908             case SEND_DISCONNECT:
5909                 connection->state = SENT_DISCONNECT;
5910                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5911                 return true;
5912 
5913             default:
5914                 break;
5915         }
5916 
5917         // no further commands if connection is about to get shut down
5918         if (connection->state == SENT_DISCONNECT) continue;
5919 
5920 #ifdef ENABLE_CLASSIC
5921 
5922         // Handling link key request requires remote supported features
5923         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
5924             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
5925             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
5926 
5927             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
5928             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
5929             if (have_link_key && security_level_sufficient){
5930                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
5931             } else {
5932                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
5933             }
5934             return true;
5935         }
5936 
5937         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
5938             log_info("denying to pin request");
5939             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
5940             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
5941             return true;
5942         }
5943 
5944         // security assessment requires remote features
5945         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
5946             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
5947             hci_ssp_assess_security_on_io_cap_request(connection);
5948             // no return here as hci_ssp_assess_security_on_io_cap_request only sets AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY or AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY
5949         }
5950 
5951         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
5952             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
5953             // set authentication requirements:
5954             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
5955             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
5956             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
5957             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
5958                 authreq |= 1;
5959             }
5960             bool bonding = hci_stack->bondable;
5961             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
5962                 // if we have received IO Cap Response, we're in responder role
5963                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
5964                 if (bonding && !remote_bonding){
5965                     log_info("Remote not bonding, dropping local flag");
5966                     bonding = false;
5967                 }
5968             }
5969             if (bonding){
5970                 if (connection->bonding_flags & BONDING_DEDICATED){
5971                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
5972                 } else {
5973                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
5974                 }
5975             }
5976             uint8_t have_oob_data = 0;
5977 #ifdef ENABLE_CLASSIC_PAIRING_OOB
5978             if (connection->classic_oob_c_192 != NULL){
5979                     have_oob_data |= 1;
5980             }
5981             if (connection->classic_oob_c_256 != NULL){
5982                 have_oob_data |= 2;
5983             }
5984 #endif
5985             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
5986             return true;
5987         }
5988 
5989         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
5990             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
5991             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
5992             return true;
5993         }
5994 
5995 #ifdef ENABLE_CLASSIC_PAIRING_OOB
5996         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
5997             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
5998             const uint8_t zero[16] = { 0 };
5999             const uint8_t * r_192 = zero;
6000             const uint8_t * c_192 = zero;
6001             const uint8_t * r_256 = zero;
6002             const uint8_t * c_256 = zero;
6003             // verify P-256 OOB
6004             if ((connection->classic_oob_c_256 != NULL) && hci_command_supported(SUPPORTED_HCI_COMMAND_REMOTE_OOB_EXTENDED_DATA_REQUEST_REPLY)) {
6005                 c_256 = connection->classic_oob_c_256;
6006                 if (connection->classic_oob_r_256 != NULL) {
6007                     r_256 = connection->classic_oob_r_256;
6008                 }
6009             }
6010             // verify P-192 OOB
6011             if ((connection->classic_oob_c_192 != NULL)) {
6012                 c_192 = connection->classic_oob_c_192;
6013                 if (connection->classic_oob_r_192 != NULL) {
6014                     r_192 = connection->classic_oob_r_192;
6015                 }
6016             }
6017 
6018             // assess security
6019             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
6020             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
6021             if (need_level_4 && !can_reach_level_4){
6022                 log_info("Level 4 required, but not possible -> abort");
6023                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
6024                 // send oob negative reply
6025                 c_256 = NULL;
6026                 c_192 = NULL;
6027             }
6028 
6029             // Reply
6030             if (c_256 != zero) {
6031                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
6032             } else if (c_192 != zero){
6033                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
6034             } else {
6035                 hci_stack->classic_oob_con_handle = connection->con_handle;
6036                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
6037             }
6038             return true;
6039         }
6040 #endif
6041 
6042         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
6043             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
6044             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
6045             return true;
6046         }
6047 
6048         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
6049             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
6050             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
6051             return true;
6052         }
6053 
6054         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
6055             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
6056             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
6057             return true;
6058         }
6059 
6060         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
6061             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
6062             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
6063             connection->state = SENT_DISCONNECT;
6064             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
6065             return true;
6066         }
6067 
6068         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
6069             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
6070             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
6071             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
6072             return true;
6073         }
6074 
6075         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
6076             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
6077             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
6078             return true;
6079         }
6080 
6081         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
6082             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
6083             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
6084             return true;
6085         }
6086 
6087         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
6088             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
6089             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
6090             return true;
6091         }
6092 
6093         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
6094             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
6095             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
6096             return true;
6097         }
6098 
6099         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
6100             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
6101             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
6102             return true;
6103         }
6104 #endif
6105 
6106         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
6107             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
6108 #ifdef ENABLE_CLASSIC
6109             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
6110 #endif
6111             if (connection->state != SENT_DISCONNECT){
6112                 connection->state = SENT_DISCONNECT;
6113                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
6114                 return true;
6115             }
6116         }
6117 
6118 #ifdef ENABLE_CLASSIC
6119         uint16_t sniff_min_interval;
6120         switch (connection->sniff_min_interval){
6121             case 0:
6122                 break;
6123             case 0xffff:
6124                 connection->sniff_min_interval = 0;
6125                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
6126                 return true;
6127             default:
6128                 sniff_min_interval = connection->sniff_min_interval;
6129                 connection->sniff_min_interval = 0;
6130                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
6131                 return true;
6132         }
6133 
6134         if (connection->sniff_subrating_max_latency != 0xffff){
6135             uint16_t max_latency = connection->sniff_subrating_max_latency;
6136             connection->sniff_subrating_max_latency = 0;
6137             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
6138             return true;
6139         }
6140 
6141         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
6142             uint8_t service_type = (uint8_t) connection->qos_service_type;
6143             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
6144             hci_send_cmd(&hci_qos_setup, connection->con_handle, 0, service_type, connection->qos_token_rate, connection->qos_peak_bandwidth, connection->qos_latency, connection->qos_delay_variation);
6145             return true;
6146         }
6147 
6148         if (connection->request_role != HCI_ROLE_INVALID){
6149             hci_role_t role = connection->request_role;
6150             connection->request_role = HCI_ROLE_INVALID;
6151             hci_send_cmd(&hci_switch_role_command, connection->address, role);
6152             return true;
6153         }
6154 #endif
6155 
6156         if (connection->gap_connection_tasks != 0){
6157 #ifdef ENABLE_CLASSIC
6158             if ((connection->gap_connection_tasks & GAP_CONNECTION_TASK_WRITE_AUTOMATIC_FLUSH_TIMEOUT) != 0){
6159                 connection->gap_connection_tasks &= ~GAP_CONNECTION_TASK_WRITE_AUTOMATIC_FLUSH_TIMEOUT;
6160                 hci_send_cmd(&hci_write_automatic_flush_timeout, connection->con_handle, hci_stack->automatic_flush_timeout);
6161                 return true;
6162             }
6163             if (connection->gap_connection_tasks & GAP_CONNECTION_TASK_WRITE_SUPERVISION_TIMEOUT){
6164                 connection->gap_connection_tasks &= ~GAP_CONNECTION_TASK_WRITE_SUPERVISION_TIMEOUT;
6165                 hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
6166                 return true;
6167             }
6168 #endif
6169             if (connection->gap_connection_tasks & GAP_CONNECTION_TASK_READ_RSSI){
6170                 connection->gap_connection_tasks &= ~GAP_CONNECTION_TASK_READ_RSSI;
6171                 hci_send_cmd(&hci_read_rssi, connection->con_handle);
6172                 return true;
6173             }
6174         }
6175 
6176 #ifdef ENABLE_BLE
6177         switch (connection->le_con_parameter_update_state){
6178             // response to L2CAP CON PARAMETER UPDATE REQUEST
6179             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
6180                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
6181                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
6182                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
6183                              0x0000, 0xffff);
6184                 return true;
6185             case CON_PARAMETER_UPDATE_REPLY:
6186                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
6187                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
6188                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
6189                              0x0000, 0xffff);
6190                 return true;
6191             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
6192                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
6193                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, connection->con_handle,
6194                              ERROR_CODE_UNACCEPTABLE_CONNECTION_PARAMETERS);
6195                 return true;
6196             default:
6197                 break;
6198         }
6199         if (connection->le_phy_update_all_phys != 0xffu){
6200             uint8_t all_phys = connection->le_phy_update_all_phys;
6201             connection->le_phy_update_all_phys = 0xff;
6202             hci_send_cmd(&hci_le_set_phy, connection->con_handle, all_phys, connection->le_phy_update_tx_phys, connection->le_phy_update_rx_phys, connection->le_phy_update_phy_options);
6203             return true;
6204         }
6205 #endif
6206     }
6207     return false;
6208 }
6209 
6210 static void hci_run(void){
6211 
6212     // stack state sub statemachines
6213     switch (hci_stack->state) {
6214         case HCI_STATE_INITIALIZING:
6215             hci_initializing_run();
6216             break;
6217         case HCI_STATE_HALTING:
6218             hci_halting_run();
6219             break;
6220         case HCI_STATE_FALLING_ASLEEP:
6221             hci_falling_asleep_run();
6222             break;
6223         default:
6224             break;
6225     }
6226 
6227     // allow to run after initialization to working transition
6228     if (hci_stack->state != HCI_STATE_WORKING){
6229         return;
6230     }
6231 
6232     bool done;
6233 
6234     // send continuation fragments first, as they block the prepared packet buffer
6235     done = hci_run_acl_fragments();
6236     if (done) return;
6237 
6238 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
6239     done = hci_run_iso_fragments();
6240     if (done) return;
6241 #endif
6242 
6243 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
6244     // send host num completed packets next as they don't require num_cmd_packets > 0
6245     if (!hci_can_send_comand_packet_transport()) return;
6246     if (hci_stack->host_completed_packets){
6247         hci_host_num_completed_packets();
6248         return;
6249     }
6250 #endif
6251 
6252     if (!hci_can_send_command_packet_now()) return;
6253 
6254     // global/non-connection oriented commands
6255 
6256 
6257 #ifdef ENABLE_CLASSIC
6258     // general gap classic
6259     done = hci_run_general_gap_classic();
6260     if (done) return;
6261 #endif
6262 
6263 #ifdef ENABLE_BLE
6264     // general gap le
6265     done = hci_run_general_gap_le();
6266     if (done) return;
6267 #endif
6268 
6269     // send pending HCI commands
6270     hci_run_general_pending_commands();
6271 }
6272 
6273 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
6274     // house-keeping
6275 
6276 #ifdef ENABLE_CLASSIC
6277     bd_addr_t addr;
6278     hci_connection_t * conn;
6279 #endif
6280 #ifdef ENABLE_LE_CENTRAL
6281     uint8_t initiator_filter_policy;
6282 #endif
6283 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
6284     uint8_t i;
6285     uint8_t num_cis;
6286     hci_con_handle_t cis_handle;
6287     uint8_t status;
6288 #endif
6289 
6290     uint16_t opcode = little_endian_read_16(packet, 0);
6291     switch (opcode) {
6292         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
6293             hci_stack->loopback_mode = packet[3];
6294             break;
6295 
6296 #ifdef ENABLE_CLASSIC
6297         case HCI_OPCODE_HCI_CREATE_CONNECTION:
6298             reverse_bd_addr(&packet[3], addr);
6299             log_info("Create_connection to %s", bd_addr_to_str(addr));
6300 
6301             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
6302             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
6303                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
6304                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
6305             }
6306 
6307             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6308             if (!conn) {
6309                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6310                 if (!conn) {
6311                     // notify client that alloc failed
6312                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
6313                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
6314                 }
6315                 conn->state = SEND_CREATE_CONNECTION;
6316                 conn->role  = HCI_ROLE_MASTER;
6317             }
6318 
6319             log_info("conn state %u", conn->state);
6320             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
6321             switch (conn->state) {
6322                 // if connection active exists
6323                 case OPEN:
6324                     // and OPEN, emit connection complete command
6325                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
6326                     // packet not sent to controller
6327                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
6328                 case RECEIVED_DISCONNECTION_COMPLETE:
6329                     // create connection triggered in disconnect complete event, let's do it now
6330                     break;
6331                 case SEND_CREATE_CONNECTION:
6332 #ifdef ENABLE_HCI_SERIALIZED_CONTROLLER_OPERATIONS
6333                     if (hci_classic_operation_active()){
6334                         return ERROR_CODE_SUCCESS;
6335                     }
6336 #endif
6337                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
6338                     break;
6339                 default:
6340                     // otherwise, just ignore as it is already in the open process
6341                     // packet not sent to controller
6342                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
6343             }
6344             conn->state = SENT_CREATE_CONNECTION;
6345 
6346             // track outgoing connection
6347             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
6348             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
6349             break;
6350 
6351 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
6352         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
6353             // setup_synchronous_connection? Voice setting at offset 22
6354             // TODO: compare to current setting if sco connection already active
6355             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
6356             break;
6357         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
6358             // accept_synchronous_connection? Voice setting at offset 18
6359             // TODO: compare to current setting if sco connection already active
6360             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
6361             // track outgoing connection
6362             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_SCO;
6363             reverse_bd_addr(&packet[3], hci_stack->outgoing_addr);
6364             break;
6365 #endif
6366 #endif
6367 
6368 #ifdef ENABLE_BLE
6369 #ifdef ENABLE_LE_CENTRAL
6370         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
6371             // white list used?
6372             initiator_filter_policy = packet[7];
6373             switch (initiator_filter_policy) {
6374                 case 0:
6375                     // whitelist not used
6376                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
6377                     break;
6378                 case 1:
6379                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
6380                     break;
6381                 default:
6382                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
6383                     break;
6384             }
6385             // track outgoing connection
6386             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
6387             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
6388             break;
6389         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
6390             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
6391             break;
6392 #endif
6393 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
6394 #ifdef ENABLE_LE_CENTRAL
6395         case HCI_OPCODE_HCI_LE_CREATE_CIS:
6396             status = ERROR_CODE_SUCCESS;
6397             num_cis = packet[3];
6398             // setup hci_iso_streams
6399             for (i=0;i<num_cis;i++){
6400                 cis_handle = (hci_con_handle_t) little_endian_read_16(packet, 4 + (4 * i));
6401                 status = hci_iso_stream_create(cis_handle);
6402                 if (status != ERROR_CODE_SUCCESS) {
6403                     break;
6404                 }
6405             }
6406             // free structs on error
6407             if (status != ERROR_CODE_SUCCESS){
6408                 hci_iso_stream_requested_finalize();
6409                 return status;
6410             }
6411             break;
6412 #endif /* ENABLE_LE_CENTRAL */
6413 #ifdef ENABLE_LE_PERIPHERAL
6414         case HCI_OPCODE_HCI_LE_ACCEPT_CIS_REQUEST:
6415             cis_handle = (hci_con_handle_t) little_endian_read_16(packet, 3);
6416             status = hci_iso_stream_create(cis_handle);
6417             if (status != ERROR_CODE_SUCCESS){
6418                 return status;
6419             }
6420             break;
6421 #endif /* ENABLE_LE_PERIPHERAL */
6422 #endif /* ENABLE_LE_ISOCHRONOUS_STREAMS */
6423 #endif /* ENABLE_BLE */
6424         default:
6425             break;
6426     }
6427 
6428     hci_stack->num_cmd_packets--;
6429 
6430     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
6431     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
6432     if (err != 0){
6433         return ERROR_CODE_HARDWARE_FAILURE;
6434     }
6435     return ERROR_CODE_SUCCESS;
6436 }
6437 
6438 // disconnect because of security block
6439 void hci_disconnect_security_block(hci_con_handle_t con_handle){
6440     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6441     if (!connection) return;
6442     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
6443 }
6444 
6445 
6446 // Configure Secure Simple Pairing
6447 
6448 #ifdef ENABLE_CLASSIC
6449 
6450 // enable will enable SSP during init
6451 void gap_ssp_set_enable(int enable){
6452     hci_stack->ssp_enable = enable;
6453 }
6454 
6455 static int hci_local_ssp_activated(void){
6456     return gap_ssp_supported() && hci_stack->ssp_enable;
6457 }
6458 
6459 // if set, BTstack will respond to io capability request using authentication requirement
6460 void gap_ssp_set_io_capability(int io_capability){
6461     hci_stack->ssp_io_capability = io_capability;
6462 }
6463 void gap_ssp_set_authentication_requirement(int authentication_requirement){
6464     hci_stack->ssp_authentication_requirement = authentication_requirement;
6465 }
6466 
6467 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
6468 void gap_ssp_set_auto_accept(int auto_accept){
6469     hci_stack->ssp_auto_accept = auto_accept;
6470 }
6471 
6472 void gap_secure_connections_enable(bool enable){
6473     hci_stack->secure_connections_enable = enable;
6474 }
6475 bool gap_secure_connections_active(void){
6476     return hci_stack->secure_connections_active;
6477 }
6478 
6479 #endif
6480 
6481 // va_list part of hci_send_cmd
6482 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
6483     if (!hci_can_send_command_packet_now()){
6484         log_error("hci_send_cmd called but cannot send packet now");
6485         return ERROR_CODE_COMMAND_DISALLOWED;
6486     }
6487 
6488     // for HCI INITIALIZATION
6489     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
6490     hci_stack->last_cmd_opcode = cmd->opcode;
6491 
6492     hci_reserve_packet_buffer();
6493     uint8_t * packet = hci_stack->hci_packet_buffer;
6494     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
6495     uint8_t status = hci_send_cmd_packet(packet, size);
6496 
6497     // release packet buffer on error or for synchronous transport implementations
6498     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
6499         hci_release_packet_buffer();
6500         hci_emit_transport_packet_sent();
6501     }
6502 
6503     return status;
6504 }
6505 
6506 /**
6507  * pre: numcmds >= 0 - it's allowed to send a command to the controller
6508  */
6509 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
6510     va_list argptr;
6511     va_start(argptr, cmd);
6512     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
6513     va_end(argptr);
6514     return status;
6515 }
6516 
6517 // Create various non-HCI events.
6518 // TODO: generalize, use table similar to hci_create_command
6519 
6520 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
6521     // dump packet
6522     if (dump) {
6523         hci_dump_packet( HCI_EVENT_PACKET, 1, event, size);
6524     }
6525 
6526     // dispatch to all event handlers
6527     btstack_linked_list_iterator_t it;
6528     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
6529     while (btstack_linked_list_iterator_has_next(&it)){
6530         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
6531         entry->callback(HCI_EVENT_PACKET, 0, event, size);
6532     }
6533 }
6534 
6535 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
6536     if (!hci_stack->acl_packet_handler) return;
6537     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
6538 }
6539 
6540 #ifdef ENABLE_CLASSIC
6541 static void hci_notify_if_sco_can_send_now(void){
6542     // notify SCO sender if waiting
6543     if (!hci_stack->sco_waiting_for_can_send_now) return;
6544     if (hci_can_send_sco_packet_now()){
6545         hci_stack->sco_waiting_for_can_send_now = 0;
6546         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
6547         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
6548         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
6549     }
6550 }
6551 
6552 // parsing end emitting has been merged to reduce code size
6553 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
6554     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
6555 
6556     uint8_t * eir_data;
6557     ad_context_t context;
6558     const uint8_t * name;
6559     uint8_t         name_len;
6560 
6561     if (size < 3) return;
6562 
6563     int event_type = hci_event_packet_get_type(packet);
6564     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
6565     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
6566 
6567     switch (event_type){
6568         case HCI_EVENT_INQUIRY_RESULT:
6569         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
6570             if (size != (3 + (num_responses * 14))) return;
6571             break;
6572         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
6573             if (size != 257) return;
6574             if (num_responses != 1) return;
6575             break;
6576         default:
6577             return;
6578     }
6579 
6580     // event[1] is set at the end
6581     int i;
6582     for (i=0; i<num_responses;i++){
6583         memset(event, 0, sizeof(event));
6584         event[0] = GAP_EVENT_INQUIRY_RESULT;
6585         uint8_t event_size = 27;    // if name is not set by EIR
6586 
6587         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
6588         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
6589         (void)memcpy(&event[9],
6590                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
6591                      3); // class of device
6592         (void)memcpy(&event[12],
6593                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
6594                      2); // clock offset
6595 
6596         switch (event_type){
6597             case HCI_EVENT_INQUIRY_RESULT:
6598                 // 14,15,16,17 = 0, size 18
6599                 break;
6600             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
6601                 event[14] = 1;
6602                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
6603                 // 16,17 = 0, size 18
6604                 break;
6605             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
6606                 event[14] = 1;
6607                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
6608                 // EIR packets only contain a single inquiry response
6609                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
6610                 name = NULL;
6611                 // Iterate over EIR data
6612                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
6613                     uint8_t data_type    = ad_iterator_get_data_type(&context);
6614                     uint8_t data_size    = ad_iterator_get_data_len(&context);
6615                     const uint8_t * data = ad_iterator_get_data(&context);
6616                     // Prefer Complete Local Name over Shortened Local Name
6617                     switch (data_type){
6618                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
6619                             if (name) continue;
6620                             /* fall through */
6621                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
6622                             name = data;
6623                             name_len = data_size;
6624                             break;
6625                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
6626                             if (data_size != 8) break;
6627                             event[16] = 1;
6628                             memcpy(&event[17], data, 8);
6629                             break;
6630                         default:
6631                             break;
6632                     }
6633                 }
6634                 if (name){
6635                     event[25] = 1;
6636                     // truncate name if needed
6637                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
6638                     event[26] = len;
6639                     (void)memcpy(&event[27], name, len);
6640                     event_size += len;
6641                 }
6642                 break;
6643             default:
6644                 return;
6645         }
6646         event[1] = event_size - 2;
6647         hci_emit_event(event, event_size, 1);
6648     }
6649 }
6650 #endif
6651 
6652 void hci_emit_state(void){
6653     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
6654     uint8_t event[3];
6655     event[0] = BTSTACK_EVENT_STATE;
6656     event[1] = sizeof(event) - 2u;
6657     event[2] = hci_stack->state;
6658     hci_emit_event(event, sizeof(event), 1);
6659 }
6660 
6661 #ifdef ENABLE_CLASSIC
6662 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
6663     uint8_t event[13];
6664     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
6665     event[1] = sizeof(event) - 2;
6666     event[2] = status;
6667     little_endian_store_16(event, 3, con_handle);
6668     reverse_bd_addr(address, &event[5]);
6669     event[11] = 1; // ACL connection
6670     event[12] = 0; // encryption disabled
6671     hci_emit_event(event, sizeof(event), 1);
6672 }
6673 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
6674     if (disable_l2cap_timeouts) return;
6675     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
6676     uint8_t event[4];
6677     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
6678     event[1] = sizeof(event) - 2;
6679     little_endian_store_16(event, 2, conn->con_handle);
6680     hci_emit_event(event, sizeof(event), 1);
6681 }
6682 #endif
6683 
6684 #ifdef ENABLE_BLE
6685 #ifdef ENABLE_LE_CENTRAL
6686 static void hci_emit_le_connection_complete(uint8_t address_type, const bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
6687     uint8_t event[21];
6688     event[0] = HCI_EVENT_LE_META;
6689     event[1] = sizeof(event) - 2u;
6690     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
6691     event[3] = status;
6692     little_endian_store_16(event, 4, con_handle);
6693     event[6] = 0; // TODO: role
6694     event[7] = address_type;
6695     reverse_bd_addr(address, &event[8]);
6696     little_endian_store_16(event, 14, 0); // interval
6697     little_endian_store_16(event, 16, 0); // latency
6698     little_endian_store_16(event, 18, 0); // supervision timeout
6699     event[20] = 0; // master clock accuracy
6700     hci_emit_event(event, sizeof(event), 1);
6701 }
6702 #endif
6703 #endif
6704 
6705 static void hci_emit_transport_packet_sent(void){
6706     // notify upper stack that it might be possible to send again
6707     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
6708     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
6709 }
6710 
6711 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
6712     uint8_t event[6];
6713     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
6714     event[1] = sizeof(event) - 2u;
6715     event[2] = 0; // status = OK
6716     little_endian_store_16(event, 3, con_handle);
6717     event[5] = reason;
6718     hci_emit_event(event, sizeof(event), 1);
6719 }
6720 
6721 static void hci_emit_nr_connections_changed(void){
6722     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
6723     uint8_t event[3];
6724     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
6725     event[1] = sizeof(event) - 2u;
6726     event[2] = nr_hci_connections();
6727     hci_emit_event(event, sizeof(event), 1);
6728 }
6729 
6730 static void hci_emit_hci_open_failed(void){
6731     log_info("BTSTACK_EVENT_POWERON_FAILED");
6732     uint8_t event[2];
6733     event[0] = BTSTACK_EVENT_POWERON_FAILED;
6734     event[1] = sizeof(event) - 2u;
6735     hci_emit_event(event, sizeof(event), 1);
6736 }
6737 
6738 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
6739     log_info("hci_emit_dedicated_bonding_result %u ", status);
6740     uint8_t event[9];
6741     int pos = 0;
6742     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
6743     event[pos++] = sizeof(event) - 2u;
6744     event[pos++] = status;
6745     reverse_bd_addr(address, &event[pos]);
6746     hci_emit_event(event, sizeof(event), 1);
6747 }
6748 
6749 
6750 #ifdef ENABLE_CLASSIC
6751 
6752 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
6753     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
6754     uint8_t event[5];
6755     int pos = 0;
6756     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
6757     event[pos++] = sizeof(event) - 2;
6758     little_endian_store_16(event, 2, con_handle);
6759     pos += 2;
6760     event[pos++] = level;
6761     hci_emit_event(event, sizeof(event), 1);
6762 }
6763 
6764 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
6765     if (!connection) return LEVEL_0;
6766     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
6767     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
6768     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
6769     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
6770     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
6771     // LEVEL 4 always requires 128 bit encrytion key size
6772     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
6773         security_level = LEVEL_3;
6774     }
6775     return security_level;
6776 }
6777 
6778 static void hci_emit_discoverable_enabled(uint8_t enabled){
6779     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
6780     uint8_t event[3];
6781     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
6782     event[1] = sizeof(event) - 2;
6783     event[2] = enabled;
6784     hci_emit_event(event, sizeof(event), 1);
6785 }
6786 
6787 // query if remote side supports eSCO
6788 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
6789     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6790     if (!connection) return false;
6791     return (connection->remote_supported_features[0] & 1) != 0;
6792 }
6793 
6794 static bool hci_ssp_supported(hci_connection_t * connection){
6795     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
6796     return (connection->bonding_flags & mask) == mask;
6797 }
6798 
6799 // query if remote side supports SSP
6800 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
6801     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6802     if (!connection) return false;
6803     return hci_ssp_supported(connection) ? 1 : 0;
6804 }
6805 
6806 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
6807     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
6808 }
6809 
6810 /**
6811  * Check if remote supported features query has completed
6812  */
6813 bool hci_remote_features_available(hci_con_handle_t handle){
6814     hci_connection_t * connection = hci_connection_for_handle(handle);
6815     if (!connection) return false;
6816     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
6817 }
6818 
6819 /**
6820  * Trigger remote supported features query
6821  */
6822 
6823 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection){
6824     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) == 0){
6825         connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
6826     }
6827 }
6828 
6829 void hci_remote_features_query(hci_con_handle_t con_handle){
6830     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6831     if (!connection) return;
6832     hci_trigger_remote_features_for_connection(connection);
6833     hci_run();
6834 }
6835 
6836 // GAP API
6837 /**
6838  * @bbrief enable/disable bonding. default is enabled
6839  * @praram enabled
6840  */
6841 void gap_set_bondable_mode(int enable){
6842     hci_stack->bondable = enable ? 1 : 0;
6843 }
6844 /**
6845  * @brief Get bondable mode.
6846  * @return 1 if bondable
6847  */
6848 int gap_get_bondable_mode(void){
6849     return hci_stack->bondable;
6850 }
6851 
6852 /**
6853  * @brief map link keys to security levels
6854  */
6855 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
6856     switch (link_key_type){
6857         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
6858             return LEVEL_4;
6859         case COMBINATION_KEY:
6860         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
6861             return LEVEL_3;
6862         default:
6863             return LEVEL_2;
6864     }
6865 }
6866 
6867 /**
6868  * @brief map link keys to secure connection yes/no
6869  */
6870 bool gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
6871     switch (link_key_type){
6872         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
6873         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
6874             return true;
6875         default:
6876             return false;
6877     }
6878 }
6879 
6880 /**
6881  * @brief map link keys to authenticated
6882  */
6883 bool gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
6884     switch (link_key_type){
6885         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
6886         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
6887             return true;
6888         default:
6889             return false;
6890     }
6891 }
6892 
6893 bool gap_mitm_protection_required_for_security_level(gap_security_level_t level){
6894     log_info("gap_mitm_protection_required_for_security_level %u", level);
6895     return level > LEVEL_2;
6896 }
6897 
6898 /**
6899  * @brief get current security level
6900  */
6901 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
6902     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6903     if (!connection) return LEVEL_0;
6904     return gap_security_level_for_connection(connection);
6905 }
6906 
6907 /**
6908  * @brief request connection to device to
6909  * @result GAP_AUTHENTICATION_RESULT
6910  */
6911 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
6912     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6913     if (!connection){
6914         hci_emit_security_level(con_handle, LEVEL_0);
6915         return;
6916     }
6917 
6918     btstack_assert(hci_is_le_connection(connection) == false);
6919 
6920     // Core Spec 5.2, GAP 5.2.2: "When in Secure Connections Only mode, all services (except those allowed to have Security Mode 4, Level 0)
6921     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
6922     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
6923         requested_level = LEVEL_4;
6924     }
6925 
6926     gap_security_level_t current_level = gap_security_level(con_handle);
6927     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
6928         requested_level, connection->requested_security_level, current_level);
6929 
6930     // authentication active if authentication request was sent or planned level > 0
6931     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
6932     if (authentication_active){
6933         // authentication already active
6934         if (connection->requested_security_level < requested_level){
6935             // increase requested level as new level is higher
6936             // TODO: handle re-authentication when done
6937             connection->requested_security_level = requested_level;
6938         }
6939     } else {
6940         // no request active, notify if security sufficient
6941         if (requested_level <= current_level){
6942             hci_emit_security_level(con_handle, current_level);
6943             return;
6944         }
6945 
6946         // store request
6947         connection->requested_security_level = requested_level;
6948 
6949         // request remote features if not already active
6950         hci_remote_features_query(con_handle);
6951 
6952         // start to authenticate connection
6953         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
6954         hci_run();
6955     }
6956 }
6957 
6958 /**
6959  * @brief start dedicated bonding with device. disconnect after bonding
6960  * @param device
6961  * @param request MITM protection
6962  * @result GAP_DEDICATED_BONDING_COMPLETE
6963  */
6964 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
6965 
6966     // create connection state machine
6967     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
6968 
6969     if (!connection){
6970         return BTSTACK_MEMORY_ALLOC_FAILED;
6971     }
6972 
6973     // delete linkn key
6974     gap_drop_link_key_for_bd_addr(device);
6975 
6976     // configure LEVEL_2/3, dedicated bonding
6977     connection->state = SEND_CREATE_CONNECTION;
6978     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
6979     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
6980     connection->bonding_flags = BONDING_DEDICATED;
6981 
6982     // wait for GAP Security Result and send GAP Dedicated Bonding complete
6983 
6984     // handle: connnection failure (connection complete != ok)
6985     // handle: authentication failure
6986     // handle: disconnect on done
6987 
6988     hci_run();
6989 
6990     return 0;
6991 }
6992 
6993 void gap_set_local_name(const char * local_name){
6994     hci_stack->local_name = local_name;
6995     hci_stack->gap_tasks_classic |= GAP_TASK_SET_LOCAL_NAME;
6996     // also update EIR if not set by user
6997     if (hci_stack->eir_data == NULL){
6998         hci_stack->gap_tasks_classic |= GAP_TASK_SET_EIR_DATA;
6999     }
7000     hci_run();
7001 }
7002 #endif
7003 
7004 
7005 #ifdef ENABLE_BLE
7006 
7007 #ifdef ENABLE_LE_CENTRAL
7008 void gap_start_scan(void){
7009     hci_stack->le_scanning_enabled = true;
7010     hci_run();
7011 }
7012 
7013 void gap_stop_scan(void){
7014     hci_stack->le_scanning_enabled = false;
7015     hci_run();
7016 }
7017 
7018 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
7019     hci_stack->le_scan_type          = scan_type;
7020     hci_stack->le_scan_filter_policy = scanning_filter_policy;
7021     hci_stack->le_scan_interval      = scan_interval;
7022     hci_stack->le_scan_window        = scan_window;
7023     hci_stack->le_scanning_param_update = true;
7024     hci_run();
7025 }
7026 
7027 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
7028     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
7029 }
7030 
7031 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
7032     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
7033     if (!conn){
7034         // disallow if le connection is already outgoing
7035         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
7036             log_error("le connection already active");
7037             return ERROR_CODE_COMMAND_DISALLOWED;
7038         }
7039 
7040         log_info("gap_connect: no connection exists yet, creating context");
7041         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
7042         if (!conn){
7043             // notify client that alloc failed
7044             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
7045             log_info("gap_connect: failed to alloc hci_connection_t");
7046             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
7047         }
7048 
7049         // set le connecting state
7050         if (hci_is_le_connection_type(addr_type)){
7051             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
7052         }
7053 
7054         conn->state = SEND_CREATE_CONNECTION;
7055         log_info("gap_connect: send create connection next");
7056         hci_run();
7057         return ERROR_CODE_SUCCESS;
7058     }
7059 
7060     if (!hci_is_le_connection(conn) ||
7061         (conn->state == SEND_CREATE_CONNECTION) ||
7062         (conn->state == SENT_CREATE_CONNECTION)) {
7063         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
7064         log_error("gap_connect: classic connection or connect is already being created");
7065         return GATT_CLIENT_IN_WRONG_STATE;
7066     }
7067 
7068     // check if connection was just disconnected
7069     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
7070         log_info("gap_connect: send create connection (again)");
7071         conn->state = SEND_CREATE_CONNECTION;
7072         hci_run();
7073         return ERROR_CODE_SUCCESS;
7074     }
7075 
7076     log_info("gap_connect: context exists with state %u", conn->state);
7077     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
7078     hci_run();
7079     return ERROR_CODE_SUCCESS;
7080 }
7081 
7082 // @assumption: only a single outgoing LE Connection exists
7083 static hci_connection_t * gap_get_outgoing_connection(void){
7084     btstack_linked_item_t *it;
7085     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
7086         hci_connection_t * conn = (hci_connection_t *) it;
7087         if (!hci_is_le_connection(conn)) continue;
7088         switch (conn->state){
7089             case SEND_CREATE_CONNECTION:
7090             case SENT_CREATE_CONNECTION:
7091             case SENT_CANCEL_CONNECTION:
7092                 return conn;
7093             default:
7094                 break;
7095         };
7096     }
7097     return NULL;
7098 }
7099 
7100 uint8_t gap_connect_cancel(void){
7101     hci_connection_t * conn = gap_get_outgoing_connection();
7102     if (!conn) return 0;
7103     switch (conn->state){
7104         case SEND_CREATE_CONNECTION:
7105             // skip sending create connection and emit event instead
7106             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
7107             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
7108             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
7109             btstack_memory_hci_connection_free( conn );
7110             break;
7111         case SENT_CREATE_CONNECTION:
7112             // request to send cancel connection
7113             conn->state = SEND_CANCEL_CONNECTION;
7114             hci_run();
7115             break;
7116         default:
7117             break;
7118     }
7119     return 0;
7120 }
7121 
7122 /**
7123  * @brief Set connection parameters for outgoing connections
7124  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
7125  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
7126  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
7127  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
7128  * @param conn_latency, default: 4
7129  * @param supervision_timeout (unit: 10ms), default: 720 ms
7130  * @param min_ce_length (unit: 0.625ms), default: 10 ms
7131  * @param max_ce_length (unit: 0.625ms), default: 30 ms
7132  */
7133 
7134 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
7135     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
7136     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
7137     hci_stack->le_connection_scan_interval = conn_scan_interval;
7138     hci_stack->le_connection_scan_window = conn_scan_window;
7139     hci_stack->le_connection_interval_min = conn_interval_min;
7140     hci_stack->le_connection_interval_max = conn_interval_max;
7141     hci_stack->le_connection_latency = conn_latency;
7142     hci_stack->le_supervision_timeout = supervision_timeout;
7143     hci_stack->le_minimum_ce_length = min_ce_length;
7144     hci_stack->le_maximum_ce_length = max_ce_length;
7145 }
7146 #endif
7147 
7148 /**
7149  * @brief Updates the connection parameters for a given LE connection
7150  * @param handle
7151  * @param conn_interval_min (unit: 1.25ms)
7152  * @param conn_interval_max (unit: 1.25ms)
7153  * @param conn_latency
7154  * @param supervision_timeout (unit: 10ms)
7155  * @return 0 if ok
7156  */
7157 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
7158     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
7159     hci_connection_t * connection = hci_connection_for_handle(con_handle);
7160     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7161     connection->le_conn_interval_min = conn_interval_min;
7162     connection->le_conn_interval_max = conn_interval_max;
7163     connection->le_conn_latency = conn_latency;
7164     connection->le_supervision_timeout = supervision_timeout;
7165     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
7166     hci_run();
7167     return 0;
7168 }
7169 
7170 /**
7171  * @brief Request an update of the connection parameter for a given LE connection
7172  * @param handle
7173  * @param conn_interval_min (unit: 1.25ms)
7174  * @param conn_interval_max (unit: 1.25ms)
7175  * @param conn_latency
7176  * @param supervision_timeout (unit: 10ms)
7177  * @return 0 if ok
7178  */
7179 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
7180     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
7181     hci_connection_t * connection = hci_connection_for_handle(con_handle);
7182     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7183     connection->le_conn_interval_min = conn_interval_min;
7184     connection->le_conn_interval_max = conn_interval_max;
7185     connection->le_conn_latency = conn_latency;
7186     connection->le_supervision_timeout = supervision_timeout;
7187     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
7188     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
7189     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
7190     return 0;
7191 }
7192 
7193 #ifdef ENABLE_LE_PERIPHERAL
7194 
7195 /**
7196  * @brief Set Advertisement Data
7197  * @param advertising_data_length
7198  * @param advertising_data (max 31 octets)
7199  * @note data is not copied, pointer has to stay valid
7200  */
7201 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
7202     hci_stack->le_advertisements_data_len = advertising_data_length;
7203     hci_stack->le_advertisements_data = advertising_data;
7204     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
7205     hci_run();
7206 }
7207 
7208 /**
7209  * @brief Set Scan Response Data
7210  * @param advertising_data_length
7211  * @param advertising_data (max 31 octets)
7212  * @note data is not copied, pointer has to stay valid
7213  */
7214 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
7215     hci_stack->le_scan_response_data_len = scan_response_data_length;
7216     hci_stack->le_scan_response_data = scan_response_data;
7217     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
7218     hci_run();
7219 }
7220 
7221 /**
7222  * @brief Set Advertisement Parameters
7223  * @param adv_int_min
7224  * @param adv_int_max
7225  * @param adv_type
7226  * @param direct_address_type
7227  * @param direct_address
7228  * @param channel_map
7229  * @param filter_policy
7230  *
7231  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
7232  */
7233  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
7234     uint8_t direct_address_typ, bd_addr_t direct_address,
7235     uint8_t channel_map, uint8_t filter_policy) {
7236 
7237     hci_stack->le_advertisements_interval_min = adv_int_min;
7238     hci_stack->le_advertisements_interval_max = adv_int_max;
7239     hci_stack->le_advertisements_type = adv_type;
7240     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
7241     hci_stack->le_advertisements_channel_map = channel_map;
7242     hci_stack->le_advertisements_filter_policy = filter_policy;
7243     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
7244                  6);
7245 
7246     hci_stack->le_advertisements_todo  |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
7247     hci_stack->le_advertisements_state |= LE_ADVERTISEMENT_STATE_PARAMS_SET;
7248     hci_run();
7249  }
7250 
7251 /**
7252  * @brief Enable/Disable Advertisements
7253  * @param enabled
7254  */
7255 void gap_advertisements_enable(int enabled){
7256     if (enabled == 0){
7257         hci_stack->le_advertisements_state &= ~LE_ADVERTISEMENT_STATE_ENABLED;
7258     } else {
7259         hci_stack->le_advertisements_state |= LE_ADVERTISEMENT_STATE_ENABLED;
7260     }
7261     hci_update_advertisements_enabled_for_current_roles();
7262     hci_run();
7263 }
7264 
7265 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
7266 static le_advertising_set_t * hci_advertising_set_for_handle(uint8_t advertising_handle){
7267     btstack_linked_list_iterator_t it;
7268     btstack_linked_list_iterator_init(&it, &hci_stack->le_advertising_sets);
7269     while (btstack_linked_list_iterator_has_next(&it)){
7270         le_advertising_set_t * item = (le_advertising_set_t *) btstack_linked_list_iterator_next(&it);
7271         if ( item->advertising_handle == advertising_handle ) {
7272             return item;
7273         }
7274     }
7275     return NULL;
7276 }
7277 
7278 uint8_t gap_extended_advertising_setup(le_advertising_set_t * storage, const le_extended_advertising_parameters_t * advertising_parameters, uint8_t * out_advertising_handle){
7279     // find free advertisement handle
7280     uint8_t advertisement_handle;
7281     for (advertisement_handle = 1; advertisement_handle <= LE_EXTENDED_ADVERTISING_MAX_HANDLE; advertisement_handle++){
7282         if (hci_advertising_set_for_handle(advertisement_handle) == NULL) break;
7283     }
7284     if (advertisement_handle > LE_EXTENDED_ADVERTISING_MAX_HANDLE) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
7285     // clear
7286     memset(storage, 0, sizeof(le_advertising_set_t));
7287     // copy params
7288     storage->advertising_handle = advertisement_handle;
7289     memcpy(&storage->extended_params, advertising_parameters, sizeof(le_extended_advertising_parameters_t));
7290     // add to list
7291     bool add_ok = btstack_linked_list_add(&hci_stack->le_advertising_sets, (btstack_linked_item_t *) storage);
7292     if (!add_ok) return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
7293     *out_advertising_handle = advertisement_handle;
7294     // set tasks and start
7295     storage->tasks = LE_ADVERTISEMENT_TASKS_SET_PARAMS;
7296     hci_run();
7297     return ERROR_CODE_SUCCESS;
7298 }
7299 
7300 uint8_t gap_extended_advertising_set_params(uint8_t advertising_handle, const le_extended_advertising_parameters_t * advertising_parameters){
7301     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7302     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7303     memcpy(&advertising_set->extended_params, advertising_parameters, sizeof(le_extended_advertising_parameters_t));
7304     // set tasks and start
7305     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
7306     hci_run();
7307     return ERROR_CODE_SUCCESS;
7308 }
7309 
7310 uint8_t gap_extended_advertising_get_params(uint8_t advertising_handle, le_extended_advertising_parameters_t * advertising_parameters){
7311     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7312     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7313     memcpy(advertising_parameters, &advertising_set->extended_params, sizeof(le_extended_advertising_parameters_t));
7314     return ERROR_CODE_SUCCESS;
7315 }
7316 
7317 uint8_t gap_extended_advertising_set_random_address(uint8_t advertising_handle, bd_addr_t random_address){
7318     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7319     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7320     memcpy(advertising_set->random_address, random_address, 6);
7321     // set tasks and start
7322     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
7323     hci_run();
7324     return ERROR_CODE_SUCCESS;
7325 }
7326 
7327 uint8_t gap_extended_advertising_set_adv_data(uint8_t advertising_handle, uint16_t advertising_data_length, const uint8_t * advertising_data){
7328     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7329     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7330     advertising_set->adv_data = advertising_data;
7331     advertising_set->adv_data_len = advertising_data_length;
7332     // set tasks and start
7333     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
7334     hci_run();
7335     return ERROR_CODE_SUCCESS;
7336 }
7337 
7338 uint8_t gap_extended_advertising_set_scan_response_data(uint8_t advertising_handle, uint16_t scan_response_data_length, const uint8_t * scan_response_data){
7339     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7340     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7341     advertising_set->scan_data = scan_response_data;
7342     advertising_set->scan_data_len = scan_response_data_length;
7343     // set tasks and start
7344     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
7345     hci_run();
7346     return ERROR_CODE_SUCCESS;
7347 }
7348 
7349 uint8_t gap_extended_advertising_start(uint8_t advertising_handle, uint16_t timeout, uint8_t num_extended_advertising_events){
7350     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7351     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7352     advertising_set->enable_timeout = timeout;
7353     advertising_set->enable_max_scan_events = num_extended_advertising_events;
7354     // set tasks and start
7355     advertising_set->state |= LE_ADVERTISEMENT_STATE_ENABLED;
7356     hci_run();
7357     return ERROR_CODE_SUCCESS;
7358 }
7359 
7360 uint8_t gap_extended_advertising_stop(uint8_t advertising_handle){
7361     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7362     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7363     // set tasks and start
7364     advertising_set->state &= ~LE_ADVERTISEMENT_STATE_ENABLED;
7365     hci_run();
7366     return ERROR_CODE_SUCCESS;
7367 }
7368 
7369 uint8_t gap_extended_advertising_remove(uint8_t advertising_handle){
7370     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7371     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7372     // set tasks and start
7373     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_REMOVE_SET;
7374     hci_run();
7375     return ERROR_CODE_SUCCESS;
7376 }
7377 
7378 #ifdef ENABLE_LE_PERIODIC_ADVERTISING
7379 uint8_t gap_periodic_advertising_set_params(uint8_t advertising_handle, const le_periodic_advertising_parameters_t * advertising_parameters){
7380     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7381     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7382     // periodic advertising requires neither connectable, scannable, legacy or anonymous
7383     if ((advertising_set->extended_params.advertising_event_properties & 0x1f) != 0) return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
7384     memcpy(&advertising_set->periodic_params, advertising_parameters, sizeof(le_periodic_advertising_parameters_t));
7385     // set tasks and start
7386     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_PERIODIC_PARAMS;
7387     hci_run();
7388     return ERROR_CODE_SUCCESS;
7389 }
7390 
7391 uint8_t gap_periodic_advertising_get_params(uint8_t advertising_handle, le_periodic_advertising_parameters_t * advertising_parameters){
7392     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7393     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7394     memcpy(advertising_parameters, &advertising_set->extended_params, sizeof(le_periodic_advertising_parameters_t));
7395     return ERROR_CODE_SUCCESS;
7396 }
7397 
7398 uint8_t gap_periodic_advertising_set_data(uint8_t advertising_handle, uint16_t periodic_data_length, const uint8_t * periodic_data){
7399     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7400     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7401     advertising_set->periodic_data = periodic_data;
7402     advertising_set->periodic_data_len = periodic_data_length;
7403     // set tasks and start
7404     advertising_set->tasks |= LE_ADVERTISEMENT_TASKS_SET_PERIODIC_DATA;
7405     hci_run();
7406     return ERROR_CODE_SUCCESS;
7407 }
7408 
7409 uint8_t gap_periodic_advertising_start(uint8_t advertising_handle, bool include_adi){
7410     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7411     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7412     // set tasks and start
7413     advertising_set->periodic_include_adi = include_adi;
7414     advertising_set->state |= LE_ADVERTISEMENT_STATE_PERIODIC_ENABLED;
7415     hci_run();
7416     return ERROR_CODE_SUCCESS;
7417 }
7418 
7419 uint8_t gap_periodic_advertising_stop(uint8_t advertising_handle){
7420     le_advertising_set_t * advertising_set = hci_advertising_set_for_handle(advertising_handle);
7421     if (advertising_set == NULL) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7422     // set tasks and start
7423     advertising_set->state &= ~LE_ADVERTISEMENT_STATE_PERIODIC_ENABLED;
7424     hci_run();
7425     return ERROR_CODE_SUCCESS;
7426 }
7427 #endif /* ENABLE_LE_PERIODIC_ADVERTISING */
7428 
7429 #endif
7430 
7431 #endif
7432 
7433 void hci_le_set_own_address_type(uint8_t own_address_type){
7434     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
7435     if (own_address_type == hci_stack->le_own_addr_type) return;
7436     hci_stack->le_own_addr_type = own_address_type;
7437 
7438 #ifdef ENABLE_LE_PERIPHERAL
7439     // update advertisement parameters, too
7440     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
7441     hci_run();
7442 #endif
7443 #ifdef ENABLE_LE_CENTRAL
7444     // note: we don't update scan parameters or modify ongoing connection attempts
7445 #endif
7446 }
7447 
7448 void hci_le_random_address_set(const bd_addr_t random_address){
7449     memcpy(hci_stack->le_random_address, random_address, 6);
7450     hci_stack->le_random_address_set = true;
7451     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
7452     hci_run();
7453 }
7454 
7455 #endif
7456 
7457 uint8_t gap_disconnect(hci_con_handle_t handle){
7458     hci_connection_t * conn = hci_connection_for_handle(handle);
7459     if (!conn){
7460         hci_emit_disconnection_complete(handle, 0);
7461         return 0;
7462     }
7463     // ignore if already disconnected
7464     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
7465         return 0;
7466     }
7467     conn->state = SEND_DISCONNECT;
7468     hci_run();
7469     return 0;
7470 }
7471 
7472 int gap_read_rssi(hci_con_handle_t con_handle){
7473     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
7474     if (hci_connection == NULL) return 0;
7475     hci_connection->gap_connection_tasks |= GAP_CONNECTION_TASK_READ_RSSI;
7476     hci_run();
7477     return 1;
7478 }
7479 
7480 /**
7481  * @brief Get connection type
7482  * @param con_handle
7483  * @result connection_type
7484  */
7485 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
7486     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
7487     if (!conn) return GAP_CONNECTION_INVALID;
7488     switch (conn->address_type){
7489         case BD_ADDR_TYPE_LE_PUBLIC:
7490         case BD_ADDR_TYPE_LE_RANDOM:
7491             return GAP_CONNECTION_LE;
7492         case BD_ADDR_TYPE_SCO:
7493             return GAP_CONNECTION_SCO;
7494         case BD_ADDR_TYPE_ACL:
7495             return GAP_CONNECTION_ACL;
7496         default:
7497             return GAP_CONNECTION_INVALID;
7498     }
7499 }
7500 
7501 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
7502     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
7503     if (!conn) return HCI_ROLE_INVALID;
7504     return (hci_role_t) conn->role;
7505 }
7506 
7507 
7508 #ifdef ENABLE_CLASSIC
7509 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
7510     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
7511     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7512     conn->request_role = role;
7513     hci_run();
7514     return ERROR_CODE_SUCCESS;
7515 }
7516 #endif
7517 
7518 #ifdef ENABLE_BLE
7519 
7520 uint8_t gap_le_set_phy(hci_con_handle_t con_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
7521     hci_connection_t * conn = hci_connection_for_handle(con_handle);
7522     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7523 
7524     conn->le_phy_update_all_phys    = all_phys;
7525     conn->le_phy_update_tx_phys     = tx_phys;
7526     conn->le_phy_update_rx_phys     = rx_phys;
7527     conn->le_phy_update_phy_options = phy_options;
7528 
7529     hci_run();
7530 
7531     return 0;
7532 }
7533 
7534 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
7535     // check if already in list
7536     btstack_linked_list_iterator_t it;
7537     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
7538     while (btstack_linked_list_iterator_has_next(&it)) {
7539         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
7540         if (entry->address_type != address_type) {
7541             continue;
7542         }
7543         if (memcmp(entry->address, address, 6) != 0) {
7544             continue;
7545         }
7546 		// disallow if already scheduled to add
7547 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
7548 			return ERROR_CODE_COMMAND_DISALLOWED;
7549 		}
7550 		// still on controller, but scheduled to remove -> re-add
7551 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
7552 		return ERROR_CODE_SUCCESS;
7553     }
7554     // alloc and add to list
7555     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
7556     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
7557     entry->address_type = address_type;
7558     (void)memcpy(entry->address, address, 6);
7559     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
7560     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
7561     return ERROR_CODE_SUCCESS;
7562 }
7563 
7564 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
7565     btstack_linked_list_iterator_t it;
7566     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
7567     while (btstack_linked_list_iterator_has_next(&it)){
7568         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
7569         if (entry->address_type != address_type) {
7570             continue;
7571         }
7572         if (memcmp(entry->address, address, 6) != 0) {
7573             continue;
7574         }
7575         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
7576             // remove from controller if already present
7577             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
7578         }  else {
7579             // directly remove entry from whitelist
7580             btstack_linked_list_iterator_remove(&it);
7581             btstack_memory_whitelist_entry_free(entry);
7582         }
7583         return ERROR_CODE_SUCCESS;
7584     }
7585     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7586 }
7587 
7588 static void hci_whitelist_clear(void){
7589     btstack_linked_list_iterator_t it;
7590     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
7591     while (btstack_linked_list_iterator_has_next(&it)){
7592         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
7593         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
7594             // remove from controller if already present
7595             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
7596             continue;
7597         }
7598         // directly remove entry from whitelist
7599         btstack_linked_list_iterator_remove(&it);
7600         btstack_memory_whitelist_entry_free(entry);
7601     }
7602 }
7603 
7604 // free all entries unconditionally
7605 static void hci_whitelist_free(void){
7606     btstack_linked_list_iterator_t lit;
7607     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
7608     while (btstack_linked_list_iterator_has_next(&lit)){
7609         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
7610         btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
7611         btstack_memory_whitelist_entry_free(entry);
7612     }
7613 }
7614 
7615 /**
7616  * @brief Clear Whitelist
7617  * @return 0 if ok
7618  */
7619 uint8_t gap_whitelist_clear(void){
7620     hci_whitelist_clear();
7621     hci_run();
7622     return ERROR_CODE_SUCCESS;
7623 }
7624 
7625 /**
7626  * @brief Add Device to Whitelist
7627  * @param address_typ
7628  * @param address
7629  * @return 0 if ok
7630  */
7631 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
7632     uint8_t status = hci_whitelist_add(address_type, address);
7633     if (status){
7634         return status;
7635     }
7636     hci_run();
7637     return ERROR_CODE_SUCCESS;
7638 }
7639 
7640 /**
7641  * @brief Remove Device from Whitelist
7642  * @param address_typ
7643  * @param address
7644  * @return 0 if ok
7645  */
7646 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
7647     uint8_t status = hci_whitelist_remove(address_type, address);
7648     if (status){
7649         return status;
7650     }
7651     hci_run();
7652     return ERROR_CODE_SUCCESS;
7653 }
7654 
7655 #ifdef ENABLE_LE_CENTRAL
7656 /**
7657  * @brief Connect with Whitelist
7658  * @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
7659  * @return - if ok
7660  */
7661 uint8_t gap_connect_with_whitelist(void){
7662     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
7663         return ERROR_CODE_COMMAND_DISALLOWED;
7664     }
7665     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
7666     hci_run();
7667     return ERROR_CODE_SUCCESS;
7668 }
7669 
7670 /**
7671  * @brief Auto Connection Establishment - Start Connecting to device
7672  * @param address_typ
7673  * @param address
7674  * @return 0 if ok
7675  */
7676 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
7677     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
7678         return ERROR_CODE_COMMAND_DISALLOWED;
7679     }
7680 
7681     uint8_t status = hci_whitelist_add(address_type, address);
7682     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
7683         return status;
7684     }
7685 
7686     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
7687 
7688     hci_run();
7689     return ERROR_CODE_SUCCESS;
7690 }
7691 
7692 /**
7693  * @brief Auto Connection Establishment - Stop Connecting to device
7694  * @param address_typ
7695  * @param address
7696  * @return 0 if ok
7697  */
7698 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
7699     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
7700         return ERROR_CODE_COMMAND_DISALLOWED;
7701     }
7702 
7703     hci_whitelist_remove(address_type, address);
7704     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
7705         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
7706     }
7707     hci_run();
7708     return 0;
7709 }
7710 
7711 /**
7712  * @brief Auto Connection Establishment - Stop everything
7713  * @note  Convenience function to stop all active auto connection attempts
7714  */
7715 uint8_t gap_auto_connection_stop_all(void){
7716     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
7717         return ERROR_CODE_COMMAND_DISALLOWED;
7718     }
7719     hci_whitelist_clear();
7720     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
7721     hci_run();
7722     return ERROR_CODE_SUCCESS;
7723 }
7724 
7725 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
7726     hci_connection_t * conn = hci_connection_for_handle(con_handle);
7727     if (!conn) return 0;
7728     return conn->le_connection_interval;
7729 }
7730 #endif
7731 #endif
7732 
7733 #ifdef ENABLE_CLASSIC
7734 /**
7735  * @brief Set Extended Inquiry Response data
7736  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
7737  * @note has to be done before stack starts up
7738  */
7739 void gap_set_extended_inquiry_response(const uint8_t * data){
7740     hci_stack->eir_data = data;
7741     hci_stack->gap_tasks_classic |= GAP_TASK_SET_EIR_DATA;
7742     hci_run();
7743 }
7744 
7745 /**
7746  * @brief Start GAP Classic Inquiry
7747  * @param duration in 1.28s units
7748  * @return 0 if ok
7749  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
7750  */
7751 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
7752     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
7753     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7754     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
7755         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
7756     }
7757     hci_stack->inquiry_state = duration_in_1280ms_units;
7758     hci_stack->inquiry_max_period_length = 0;
7759     hci_stack->inquiry_min_period_length = 0;
7760     hci_run();
7761     return 0;
7762 }
7763 
7764 uint8_t gap_inquiry_periodic_start(uint8_t duration, uint16_t max_period_length, uint16_t min_period_length){
7765     if (hci_stack->state != HCI_STATE_WORKING)                return ERROR_CODE_COMMAND_DISALLOWED;
7766     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE)   return ERROR_CODE_COMMAND_DISALLOWED;
7767     if (duration < GAP_INQUIRY_DURATION_MIN)                  return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
7768     if (duration > GAP_INQUIRY_DURATION_MAX)                  return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
7769     if (max_period_length < GAP_INQUIRY_MAX_PERIODIC_LEN_MIN) return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;;
7770     if (min_period_length < GAP_INQUIRY_MIN_PERIODIC_LEN_MIN) return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;;
7771 
7772     hci_stack->inquiry_state = duration;
7773     hci_stack->inquiry_max_period_length = max_period_length;
7774     hci_stack->inquiry_min_period_length = min_period_length;
7775     hci_run();
7776     return 0;
7777 }
7778 
7779 /**
7780  * @brief Stop GAP Classic Inquiry
7781  * @return 0 if ok
7782  */
7783 int gap_inquiry_stop(void){
7784     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
7785         // emit inquiry complete event, before it even started
7786         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
7787         hci_emit_event(event, sizeof(event), 1);
7788         return 0;
7789     }
7790     switch (hci_stack->inquiry_state){
7791         case GAP_INQUIRY_STATE_ACTIVE:
7792             hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
7793             hci_run();
7794             return ERROR_CODE_SUCCESS;
7795         case GAP_INQUIRY_STATE_PERIODIC:
7796             hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_EXIT_PERIODIC;
7797             hci_run();
7798             return ERROR_CODE_SUCCESS;
7799         default:
7800             return ERROR_CODE_COMMAND_DISALLOWED;
7801     }
7802 }
7803 
7804 void gap_inquiry_set_lap(uint32_t lap){
7805     hci_stack->inquiry_lap = lap;
7806 }
7807 
7808 void gap_inquiry_set_scan_activity(uint16_t inquiry_scan_interval, uint16_t inquiry_scan_window){
7809     hci_stack->inquiry_scan_interval = inquiry_scan_interval;
7810     hci_stack->inquiry_scan_window   = inquiry_scan_window;
7811     hci_stack->gap_tasks_classic |= GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
7812     hci_run();
7813 }
7814 
7815 
7816 /**
7817  * @brief Remote Name Request
7818  * @param addr
7819  * @param page_scan_repetition_mode
7820  * @param clock_offset only used when bit 15 is set
7821  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
7822  */
7823 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
7824     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7825     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
7826     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
7827     hci_stack->remote_name_clock_offset = clock_offset;
7828     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
7829     hci_run();
7830     return 0;
7831 }
7832 
7833 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
7834     hci_stack->gap_pairing_state = state;
7835     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
7836     hci_run();
7837     return 0;
7838 }
7839 
7840 /**
7841  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
7842  * @param addr
7843  * @param pin_data
7844  * @param pin_len
7845  * @return 0 if ok
7846  */
7847 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
7848     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7849     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
7850     hci_stack->gap_pairing_pin_len = pin_len;
7851     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
7852 }
7853 
7854 /**
7855  * @brief Legacy Pairing Pin Code Response
7856  * @param addr
7857  * @param pin
7858  * @return 0 if ok
7859  */
7860 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
7861     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
7862 }
7863 
7864 /**
7865  * @brief Abort Legacy Pairing
7866  * @param addr
7867  * @param pin
7868  * @return 0 if ok
7869  */
7870 int gap_pin_code_negative(bd_addr_t addr){
7871     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7872     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
7873 }
7874 
7875 /**
7876  * @brief SSP Passkey Response
7877  * @param addr
7878  * @param passkey
7879  * @return 0 if ok
7880  */
7881 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
7882     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7883     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
7884     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
7885 }
7886 
7887 /**
7888  * @brief Abort SSP Passkey Entry/Pairing
7889  * @param addr
7890  * @param pin
7891  * @return 0 if ok
7892  */
7893 int gap_ssp_passkey_negative(const bd_addr_t addr){
7894     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7895     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
7896 }
7897 
7898 /**
7899  * @brief Accept SSP Numeric Comparison
7900  * @param addr
7901  * @param passkey
7902  * @return 0 if ok
7903  */
7904 int gap_ssp_confirmation_response(const bd_addr_t addr){
7905     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7906     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
7907 }
7908 
7909 /**
7910  * @brief Abort SSP Numeric Comparison/Pairing
7911  * @param addr
7912  * @param pin
7913  * @return 0 if ok
7914  */
7915 int gap_ssp_confirmation_negative(const bd_addr_t addr){
7916     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
7917     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
7918 }
7919 
7920 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
7921 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
7922     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
7923     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7924     connectionSetAuthenticationFlags(conn, flag);
7925     hci_run();
7926     return ERROR_CODE_SUCCESS;
7927 }
7928 #endif
7929 
7930 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
7931 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
7932     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
7933 }
7934 
7935 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
7936     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
7937 }
7938 #endif
7939 
7940 #ifdef ENABLE_CLASSIC_PAIRING_OOB
7941 /**
7942  * @brief Report Remote OOB Data
7943  * @param bd_addr
7944  * @param c_192 Simple Pairing Hash C derived from P-192 public key
7945  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
7946  * @param c_256 Simple Pairing Hash C derived from P-256 public key
7947  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
7948  */
7949 uint8_t gap_ssp_remote_oob_data(const bd_addr_t addr, const uint8_t * c_192, const uint8_t * r_192, const uint8_t * c_256, const uint8_t * r_256){
7950     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
7951     if (connection == NULL) {
7952         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7953     }
7954     connection->classic_oob_c_192 = c_192;
7955     connection->classic_oob_r_192 = r_192;
7956 
7957     // ignore P-256 if not supported by us
7958     if (hci_stack->secure_connections_active){
7959         connection->classic_oob_c_256 = c_256;
7960         connection->classic_oob_r_256 = r_256;
7961     }
7962 
7963     return ERROR_CODE_SUCCESS;
7964 }
7965 /**
7966  * @brief Generate new OOB data
7967  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
7968  */
7969 void gap_ssp_generate_oob_data(void){
7970     hci_stack->classic_read_local_oob_data = true;
7971     hci_run();
7972 }
7973 
7974 #endif
7975 
7976 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
7977 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
7978     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
7979     if (connection == NULL) {
7980         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
7981     }
7982 
7983     memcpy(connection->link_key, link_key, sizeof(link_key_t));
7984     connection->link_key_type = type;
7985 
7986     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
7987 }
7988 
7989 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
7990 /**
7991  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
7992  * @param inquiry_mode see bluetooth_defines.h
7993  */
7994 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
7995     hci_stack->inquiry_mode = inquiry_mode;
7996 }
7997 
7998 /**
7999  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
8000  */
8001 void hci_set_sco_voice_setting(uint16_t voice_setting){
8002     hci_stack->sco_voice_setting = voice_setting;
8003 }
8004 
8005 /**
8006  * @brief Get SCO Voice Setting
8007  * @return current voice setting
8008  */
8009 uint16_t hci_get_sco_voice_setting(void){
8010     return hci_stack->sco_voice_setting;
8011 }
8012 
8013 static int hci_have_usb_transport(void){
8014     if (!hci_stack->hci_transport) return 0;
8015     const char * transport_name = hci_stack->hci_transport->name;
8016     if (!transport_name) return 0;
8017     return (transport_name[0] == 'H') && (transport_name[1] == '2');
8018 }
8019 
8020 /** @brief Get SCO packet length for current SCO Voice setting
8021  *  @note  Using SCO packets of the exact length is required for USB transfer
8022  *  @return Length of SCO packets in bytes (not audio frames)
8023  */
8024 uint16_t hci_get_sco_packet_length(void){
8025     uint16_t sco_packet_length = 0;
8026 
8027 #ifdef ENABLE_SCO_OVER_HCI
8028     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
8029     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
8030 
8031     if (hci_have_usb_transport()){
8032         // see Core Spec for H2 USB Transfer.
8033         // 3 byte SCO header + 24 bytes per connection
8034         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
8035         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
8036     } else {
8037         // 3 byte SCO header + SCO packet size over the air (60 bytes)
8038         sco_packet_length = 3 + 60 * multiplier;
8039         // assert that it still fits inside an SCO buffer
8040         if (sco_packet_length > hci_stack->sco_data_packet_length){
8041             sco_packet_length = 3 + 60;
8042         }
8043     }
8044 #endif
8045 
8046 #ifdef HAVE_SCO_TRANSPORT
8047     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
8048     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
8049     sco_packet_length = 3 + 60 * multiplier;
8050 #endif
8051     return sco_packet_length;
8052 }
8053 
8054 /**
8055 * @brief Sets the master/slave policy
8056 * @param policy (0: attempt to become master, 1: let connecting device decide)
8057 */
8058 void hci_set_master_slave_policy(uint8_t policy){
8059     hci_stack->master_slave_policy = policy;
8060 }
8061 
8062 #endif
8063 
8064 HCI_STATE hci_get_state(void){
8065     return hci_stack->state;
8066 }
8067 
8068 #ifdef ENABLE_CLASSIC
8069 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
8070     hci_stack->gap_classic_accept_callback = accept_callback;
8071 }
8072 #endif
8073 
8074 /**
8075  * @brief Set callback for Bluetooth Hardware Error
8076  */
8077 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
8078     hci_stack->hardware_error_callback = fn;
8079 }
8080 
8081 void hci_disconnect_all(void){
8082     btstack_linked_list_iterator_t it;
8083     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
8084     while (btstack_linked_list_iterator_has_next(&it)){
8085         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
8086         if (con->state == SENT_DISCONNECT) continue;
8087         con->state = SEND_DISCONNECT;
8088     }
8089     hci_run();
8090 }
8091 
8092 uint16_t hci_get_manufacturer(void){
8093     return hci_stack->manufacturer;
8094 }
8095 
8096 #ifdef ENABLE_BLE
8097 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
8098     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
8099     if (!hci_con) return NULL;
8100     return &hci_con->sm_connection;
8101 }
8102 
8103 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
8104 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
8105 #endif
8106 
8107 uint8_t gap_encryption_key_size(hci_con_handle_t con_handle){
8108     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
8109     if (hci_connection == NULL) return 0;
8110     if (hci_is_le_connection(hci_connection)){
8111 #ifdef ENABLE_BLE
8112         sm_connection_t * sm_conn = &hci_connection->sm_connection;
8113         if (sm_conn->sm_connection_encrypted) {
8114             return sm_conn->sm_actual_encryption_key_size;
8115         }
8116 #endif
8117     } else {
8118 #ifdef ENABLE_CLASSIC
8119         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
8120             return hci_connection->encryption_key_size;
8121         }
8122 #endif
8123     }
8124     return 0;
8125 }
8126 
8127 bool gap_authenticated(hci_con_handle_t con_handle){
8128     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
8129     if (hci_connection == NULL) return false;
8130 
8131     switch (hci_connection->address_type){
8132 #ifdef ENABLE_BLE
8133         case BD_ADDR_TYPE_LE_PUBLIC:
8134         case BD_ADDR_TYPE_LE_RANDOM:
8135             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
8136             return hci_connection->sm_connection.sm_connection_authenticated != 0;
8137 #endif
8138 #ifdef ENABLE_CLASSIC
8139         case BD_ADDR_TYPE_SCO:
8140         case BD_ADDR_TYPE_ACL:
8141             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
8142 #endif
8143         default:
8144             return false;
8145     }
8146 }
8147 
8148 bool gap_secure_connection(hci_con_handle_t con_handle){
8149     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
8150     if (hci_connection == NULL) return 0;
8151 
8152     switch (hci_connection->address_type){
8153 #ifdef ENABLE_BLE
8154         case BD_ADDR_TYPE_LE_PUBLIC:
8155         case BD_ADDR_TYPE_LE_RANDOM:
8156             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return false; // unencrypted connection cannot be authenticated
8157             return hci_connection->sm_connection.sm_connection_sc != 0;
8158 #endif
8159 #ifdef ENABLE_CLASSIC
8160         case BD_ADDR_TYPE_SCO:
8161         case BD_ADDR_TYPE_ACL:
8162             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
8163 #endif
8164         default:
8165             return false;
8166     }
8167 }
8168 
8169 bool gap_bonded(hci_con_handle_t con_handle){
8170 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
8171 	if (hci_connection == NULL) return 0;
8172 
8173 #ifdef ENABLE_CLASSIC
8174 	link_key_t link_key;
8175 	link_key_type_t link_key_type;
8176 #endif
8177 	switch (hci_connection->address_type){
8178 #ifdef ENABLE_BLE
8179 		case BD_ADDR_TYPE_LE_PUBLIC:
8180 		case BD_ADDR_TYPE_LE_RANDOM:
8181 			return hci_connection->sm_connection.sm_le_db_index >= 0;
8182 #endif
8183 #ifdef ENABLE_CLASSIC
8184 		case BD_ADDR_TYPE_SCO:
8185 		case BD_ADDR_TYPE_ACL:
8186 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
8187 #endif
8188 		default:
8189 			return false;
8190 	}
8191 }
8192 
8193 #ifdef ENABLE_BLE
8194 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
8195     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
8196     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
8197     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
8198     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
8199     return sm_conn->sm_connection_authorization_state;
8200 }
8201 #endif
8202 
8203 #ifdef ENABLE_CLASSIC
8204 uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout){
8205     hci_connection_t * conn = hci_connection_for_handle(con_handle);
8206     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
8207     conn->sniff_min_interval = sniff_min_interval;
8208     conn->sniff_max_interval = sniff_max_interval;
8209     conn->sniff_attempt = sniff_attempt;
8210     conn->sniff_timeout = sniff_timeout;
8211     hci_run();
8212     return 0;
8213 }
8214 
8215 /**
8216  * @brief Exit Sniff mode
8217  * @param con_handle
8218  @ @return 0 if ok
8219  */
8220 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
8221     hci_connection_t * conn = hci_connection_for_handle(con_handle);
8222     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
8223     conn->sniff_min_interval = 0xffff;
8224     hci_run();
8225     return 0;
8226 }
8227 
8228 uint8_t gap_sniff_subrating_configure(hci_con_handle_t con_handle, uint16_t max_latency, uint16_t min_remote_timeout, uint16_t min_local_timeout){
8229     hci_connection_t * conn = hci_connection_for_handle(con_handle);
8230     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
8231     conn->sniff_subrating_max_latency = max_latency;
8232     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
8233     conn->sniff_subrating_min_local_timeout = min_local_timeout;
8234     hci_run();
8235     return ERROR_CODE_SUCCESS;
8236 }
8237 
8238 uint8_t gap_qos_set(hci_con_handle_t con_handle, hci_service_type_t service_type, uint32_t token_rate, uint32_t peak_bandwidth, uint32_t latency, uint32_t delay_variation){
8239     hci_connection_t * conn = hci_connection_for_handle(con_handle);
8240     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
8241     conn->qos_service_type = service_type;
8242     conn->qos_token_rate = token_rate;
8243     conn->qos_peak_bandwidth = peak_bandwidth;
8244     conn->qos_latency = latency;
8245     conn->qos_delay_variation = delay_variation;
8246     hci_run();
8247     return ERROR_CODE_SUCCESS;
8248 }
8249 
8250 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
8251     hci_stack->new_page_scan_interval = page_scan_interval;
8252     hci_stack->new_page_scan_window = page_scan_window;
8253     hci_stack->gap_tasks_classic |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
8254     hci_run();
8255 }
8256 
8257 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
8258     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
8259     hci_stack->gap_tasks_classic |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
8260     hci_run();
8261 }
8262 
8263 void gap_set_page_timeout(uint16_t page_timeout){
8264     hci_stack->page_timeout = page_timeout;
8265     hci_stack->gap_tasks_classic |= GAP_TASK_WRITE_PAGE_TIMEOUT;
8266     hci_run();
8267 }
8268 
8269 #endif
8270 
8271 void hci_halting_defer(void){
8272     if (hci_stack->state != HCI_STATE_HALTING) return;
8273     switch (hci_stack->substate){
8274         case HCI_HALTING_READY_FOR_CLOSE:
8275             hci_stack->substate = HCI_HALTING_DEFER_CLOSE;
8276             break;
8277         default:
8278             break;
8279     }
8280 }
8281 
8282 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
8283 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
8284     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
8285     if (le_device_db_index >= le_device_db_max_count()) return;
8286     uint8_t offset = le_device_db_index >> 3;
8287     uint8_t mask = 1 << (le_device_db_index & 7);
8288     hci_stack->le_resolving_list_add_entries[offset] |= mask;
8289     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
8290     	// note: go back to remove entries, otherwise, a remove + add will skip the add
8291         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
8292     }
8293 }
8294 
8295 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
8296 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
8297 	if (le_device_db_index >= le_device_db_max_count()) return;
8298 	uint8_t offset = le_device_db_index >> 3;
8299 	uint8_t mask = 1 << (le_device_db_index & 7);
8300 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
8301 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
8302 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
8303 	}
8304 }
8305 
8306 uint8_t gap_load_resolving_list_from_le_device_db(void){
8307     if (hci_command_supported(SUPPORTED_HCI_COMMAND_LE_SET_ADDRESS_RESOLUTION_ENABLE) == false){
8308 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
8309 	}
8310 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
8311 		// restart le resolving list update
8312 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
8313 	}
8314 	return ERROR_CODE_SUCCESS;
8315 }
8316 #endif
8317 
8318 #ifdef ENABLE_BLE
8319 #ifdef ENABLE_LE_CENTRAL
8320 #ifdef ENABLE_LE_EXTENDED_ADVERTISING
8321 
8322 static uint8_t hci_periodic_advertiser_list_add(bd_addr_type_t address_type, const bd_addr_t address, uint8_t advertising_sid){
8323     // check if already in list
8324     btstack_linked_list_iterator_t it;
8325     btstack_linked_list_iterator_init(&it, &hci_stack->le_periodic_advertiser_list);
8326     while (btstack_linked_list_iterator_has_next(&it)) {
8327         periodic_advertiser_list_entry_t *entry = (periodic_advertiser_list_entry_t *) btstack_linked_list_iterator_next(&it);
8328         if (entry->sid != advertising_sid) {
8329             continue;
8330         }
8331         if (entry->address_type != address_type) {
8332             continue;
8333         }
8334         if (memcmp(entry->address, address, 6) != 0) {
8335             continue;
8336         }
8337         // disallow if already scheduled to add
8338         if ((entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER) != 0){
8339             return ERROR_CODE_COMMAND_DISALLOWED;
8340         }
8341         // still on controller, but scheduled to remove -> re-add
8342         entry->state |= LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER;
8343         return ERROR_CODE_SUCCESS;
8344     }
8345     // alloc and add to list
8346     periodic_advertiser_list_entry_t * entry = btstack_memory_periodic_advertiser_list_entry_get();
8347     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
8348     entry->sid = advertising_sid;
8349     entry->address_type = address_type;
8350     (void)memcpy(entry->address, address, 6);
8351     entry->state = LE_PERIODIC_ADVERTISER_LIST_ENTRY_ADD_TO_CONTROLLER;
8352     btstack_linked_list_add(&hci_stack->le_periodic_advertiser_list, (btstack_linked_item_t*) entry);
8353     return ERROR_CODE_SUCCESS;
8354 }
8355 
8356 static uint8_t hci_periodic_advertiser_list_remove(bd_addr_type_t address_type, const bd_addr_t address, uint8_t advertising_sid){
8357     btstack_linked_list_iterator_t it;
8358     btstack_linked_list_iterator_init(&it, &hci_stack->le_periodic_advertiser_list);
8359     while (btstack_linked_list_iterator_has_next(&it)){
8360         periodic_advertiser_list_entry_t * entry = (periodic_advertiser_list_entry_t*) btstack_linked_list_iterator_next(&it);
8361         if (entry->sid != advertising_sid) {
8362             continue;
8363         }
8364         if (entry->address_type != address_type) {
8365             continue;
8366         }
8367         if (memcmp(entry->address, address, 6) != 0) {
8368             continue;
8369         }
8370         if (entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_ON_CONTROLLER){
8371             // remove from controller if already present
8372             entry->state |= LE_PERIODIC_ADVERTISER_LIST_ENTRY_REMOVE_FROM_CONTROLLER;
8373         }  else {
8374             // directly remove entry from whitelist
8375             btstack_linked_list_iterator_remove(&it);
8376             btstack_memory_periodic_advertiser_list_entry_free(entry);
8377         }
8378         return ERROR_CODE_SUCCESS;
8379     }
8380     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
8381 }
8382 
8383 static void hci_periodic_advertiser_list_clear(void){
8384     btstack_linked_list_iterator_t it;
8385     btstack_linked_list_iterator_init(&it, &hci_stack->le_periodic_advertiser_list);
8386     while (btstack_linked_list_iterator_has_next(&it)){
8387         periodic_advertiser_list_entry_t * entry = (periodic_advertiser_list_entry_t*) btstack_linked_list_iterator_next(&it);
8388         if (entry->state & LE_PERIODIC_ADVERTISER_LIST_ENTRY_ON_CONTROLLER){
8389             // remove from controller if already present
8390             entry->state |= LE_PERIODIC_ADVERTISER_LIST_ENTRY_REMOVE_FROM_CONTROLLER;
8391             continue;
8392         }
8393         // directly remove entry from whitelist
8394         btstack_linked_list_iterator_remove(&it);
8395         btstack_memory_periodic_advertiser_list_entry_free(entry);
8396     }
8397 }
8398 
8399 // free all entries unconditionally
8400 static void hci_periodic_advertiser_list_free(void){
8401     btstack_linked_list_iterator_t lit;
8402     btstack_linked_list_iterator_init(&lit, &hci_stack->le_periodic_advertiser_list);
8403     while (btstack_linked_list_iterator_has_next(&lit)){
8404         periodic_advertiser_list_entry_t * entry = (periodic_advertiser_list_entry_t*) btstack_linked_list_iterator_next(&lit);
8405         btstack_linked_list_remove(&hci_stack->le_periodic_advertiser_list, (btstack_linked_item_t *) entry);
8406         btstack_memory_periodic_advertiser_list_entry_free(entry);
8407     }
8408 }
8409 
8410 uint8_t gap_periodic_advertiser_list_clear(void){
8411     hci_periodic_advertiser_list_clear();
8412     hci_run();
8413     return ERROR_CODE_SUCCESS;
8414 }
8415 
8416 uint8_t gap_periodic_advertiser_list_add(bd_addr_type_t address_type, const bd_addr_t address, uint8_t advertising_sid){
8417     uint8_t status = hci_periodic_advertiser_list_add(address_type, address, advertising_sid);
8418     if (status){
8419         return status;
8420     }
8421     hci_run();
8422     return ERROR_CODE_SUCCESS;
8423 }
8424 
8425 uint8_t gap_periodic_advertiser_list_remove(bd_addr_type_t address_type, const bd_addr_t address, uint8_t advertising_sid){
8426     uint8_t status = hci_periodic_advertiser_list_remove(address_type, address, advertising_sid);
8427     if (status){
8428         return status;
8429     }
8430     hci_run();
8431     return ERROR_CODE_SUCCESS;
8432 }
8433 
8434 uint8_t gap_periodic_advertising_create_sync(uint8_t options, uint8_t advertising_sid, bd_addr_type_t advertiser_address_type,
8435                                              bd_addr_t advertiser_address, uint16_t skip, uint16_t sync_timeout, uint8_t sync_cte_type){
8436     // abort if already active
8437     if (hci_stack->le_periodic_sync_request != LE_CONNECTING_IDLE) {
8438         return ERROR_CODE_COMMAND_DISALLOWED;
8439     }
8440     // store request
8441     hci_stack->le_periodic_sync_request = ((options & 0) != 0) ? LE_CONNECTING_WHITELIST : LE_CONNECTING_DIRECT;
8442     hci_stack->le_periodic_sync_options = options;
8443     hci_stack->le_periodic_sync_advertising_sid = advertising_sid;
8444     hci_stack->le_periodic_sync_advertiser_address_type = advertiser_address_type;
8445     memcpy(hci_stack->le_periodic_sync_advertiser_address, advertiser_address, 6);
8446     hci_stack->le_periodic_sync_skip = skip;
8447     hci_stack->le_periodic_sync_timeout = sync_timeout;
8448     hci_stack->le_periodic_sync_cte_type = sync_cte_type;
8449 
8450     hci_run();
8451     return ERROR_CODE_SUCCESS;
8452 }
8453 
8454 uint8_t gap_periodic_advertising_create_sync_cancel(void){
8455     // abort if not requested
8456     if (hci_stack->le_periodic_sync_request == LE_CONNECTING_IDLE) {
8457         return ERROR_CODE_COMMAND_DISALLOWED;
8458     }
8459     hci_stack->le_periodic_sync_request = LE_CONNECTING_IDLE;
8460     hci_run();
8461     return ERROR_CODE_SUCCESS;
8462 }
8463 
8464 uint8_t gap_periodic_advertising_terminate_sync(uint16_t sync_handle){
8465     if (hci_stack->le_periodic_terminate_sync_handle != HCI_CON_HANDLE_INVALID){
8466         return ERROR_CODE_COMMAND_DISALLOWED;
8467     }
8468     hci_stack->le_periodic_terminate_sync_handle = sync_handle;
8469     hci_run();
8470     return ERROR_CODE_SUCCESS;
8471 }
8472 
8473 #endif
8474 #endif
8475 #ifdef ENABLE_LE_ISOCHRONOUS_STREAMS
8476 static uint8_t hci_iso_stream_create(hci_con_handle_t cis_handle){
8477     hci_iso_stream_t * iso_stream = btstack_memory_hci_iso_stream_get();
8478     if (iso_stream == NULL){
8479         return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
8480     } else {
8481         iso_stream->state = HCI_ISO_STREAM_STATE_REQUESTED;
8482         iso_stream->con_handle = cis_handle;
8483         btstack_linked_list_add(&hci_stack->iso_streams, (btstack_linked_item_t*) iso_stream);
8484         return ERROR_CODE_SUCCESS;
8485     }
8486 }
8487 
8488 static hci_iso_stream_t * hci_iso_stream_for_cis_handle(hci_con_handle_t cis_handle){
8489     btstack_linked_list_iterator_t it;
8490     btstack_linked_list_iterator_init(&it, &hci_stack->iso_streams);
8491     while (btstack_linked_list_iterator_has_next(&it)){
8492         hci_iso_stream_t * iso_stream = (hci_iso_stream_t *) btstack_linked_list_iterator_next(&it);
8493         if ( iso_stream->con_handle == cis_handle ) {
8494             return iso_stream;
8495         }
8496     }
8497     return NULL;
8498 }
8499 
8500 static void hci_iso_stream_finalize(hci_iso_stream_t * iso_stream){
8501     btstack_linked_list_remove(&hci_stack->iso_streams, (btstack_linked_item_t*) iso_stream);
8502     btstack_memory_hci_iso_stream_free(iso_stream);
8503 }
8504 
8505 static void hci_iso_stream_requested_finalize(void){
8506     btstack_linked_list_iterator_t it;
8507     btstack_linked_list_iterator_init(&it, &hci_stack->iso_streams);
8508     while (btstack_linked_list_iterator_has_next(&it)){
8509         hci_iso_stream_t * iso_stream = (hci_iso_stream_t *) btstack_linked_list_iterator_next(&it);
8510         if ( iso_stream->state == HCI_ISO_STREAM_STATE_REQUESTED ) {
8511             btstack_linked_list_iterator_remove(&it);
8512             btstack_memory_hci_iso_stream_free(iso_stream);
8513         }
8514     }
8515 }
8516 static void hci_iso_stream_requested_confirm(void){
8517     btstack_linked_list_iterator_t it;
8518     btstack_linked_list_iterator_init(&it, &hci_stack->iso_streams);
8519     while (btstack_linked_list_iterator_has_next(&it)){
8520         hci_iso_stream_t * iso_stream = (hci_iso_stream_t *) btstack_linked_list_iterator_next(&it);
8521         if ( iso_stream->state == HCI_ISO_STREAM_STATE_REQUESTED ) {
8522             iso_stream->state = HCI_ISO_STREAM_STATE_W4_ESTABLISHED;
8523         }
8524     }
8525 }
8526 
8527 static bool hci_iso_sdu_complete(uint8_t * packet, uint16_t size){
8528     uint8_t  sdu_ts_flag = (packet[1] >> 6) & 1;
8529     uint16_t sdu_len_offset = 6 + (sdu_ts_flag * 4);
8530     uint16_t sdu_len = little_endian_read_16(packet, sdu_len_offset) & 0x0fff;
8531     return (sdu_len_offset + 2 + sdu_len) == size;
8532 }
8533 
8534 static void hci_iso_packet_handler(uint8_t * packet, uint16_t size){
8535     if (hci_stack->iso_packet_handler == NULL) {
8536         return;
8537     }
8538     if (size < 4) {
8539         return;
8540     }
8541 
8542     // parse header
8543     uint16_t conn_handle_and_flags = little_endian_read_16(packet, 0);
8544     uint16_t iso_data_len = little_endian_read_16(packet, 2);
8545     hci_con_handle_t cis_handle = (hci_con_handle_t) (conn_handle_and_flags & 0xfff);
8546     hci_iso_stream_t * iso_stream = hci_iso_stream_for_cis_handle(cis_handle);
8547     uint8_t pb_flag = (conn_handle_and_flags >> 12) & 3;
8548 
8549     // assert packet is complete
8550     if ((iso_data_len + 4u) != size){
8551         return;
8552     }
8553 
8554     if ((pb_flag & 0x01) == 0){
8555         if (pb_flag == 0x02){
8556             // The ISO_Data_Load field contains a header and a complete SDU.
8557             if (hci_iso_sdu_complete(packet, size)) {
8558                 (hci_stack->iso_packet_handler)(HCI_ISO_DATA_PACKET, 0, packet, size);
8559             }
8560         } else {
8561             // The ISO_Data_Load field contains a header and the first fragment of a fragmented SDU.
8562             if (iso_stream == NULL){
8563                 return;
8564             }
8565             if (size > HCI_ISO_PAYLOAD_SIZE){
8566                 return;
8567             }
8568             memcpy(iso_stream->reassembly_buffer, packet, size);
8569             // fix pb_flag
8570             iso_stream->reassembly_buffer[1] = (iso_stream->reassembly_buffer[1] & 0xcf) | 0x20;
8571             iso_stream->reassembly_pos = size;
8572         }
8573     } else {
8574         // iso_data_load contains continuation or last fragment of an SDU
8575         uint8_t  ts_flag = (conn_handle_and_flags >> 14) & 1;
8576         if (ts_flag != 0){
8577            return;
8578         }
8579         // append fragment
8580         if (iso_stream == NULL){
8581             return;
8582         }
8583         if (iso_stream->reassembly_pos == 0){
8584             return;
8585         }
8586         if ((iso_stream->reassembly_pos + iso_data_len) > size){
8587             // reset reassembly buffer
8588             iso_stream->reassembly_pos = 0;
8589             return;
8590         }
8591         memcpy(&iso_stream->reassembly_buffer[iso_stream->reassembly_pos], &packet[4], iso_data_len);
8592         iso_stream->reassembly_pos += iso_data_len;
8593 
8594         // deliver if last fragment and SDU complete
8595         if (pb_flag == 0x03){
8596             if (hci_iso_sdu_complete(iso_stream->reassembly_buffer, iso_stream->reassembly_pos)){
8597                 (hci_stack->iso_packet_handler)(HCI_ISO_DATA_PACKET, 0, iso_stream->reassembly_buffer, iso_stream->reassembly_pos);
8598             }
8599             iso_stream->reassembly_pos = 0;
8600         }
8601     }
8602 }
8603 
8604 
8605 #endif
8606 #endif /* ENABLE_BLE */
8607 
8608 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
8609 void hci_setup_test_connections_fuzz(void){
8610     hci_connection_t * conn;
8611 
8612     // default address: 66:55:44:33:00:01
8613     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
8614 
8615     // setup Controller info
8616     hci_stack->num_cmd_packets = 255;
8617     hci_stack->acl_packets_total_num = 255;
8618 
8619     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
8620     addr[5] = 0x01;
8621     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
8622     conn->con_handle = addr[5];
8623     conn->role  = HCI_ROLE_SLAVE;
8624     conn->state = RECEIVED_CONNECTION_REQUEST;
8625     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
8626 
8627     // setup incoming Classic SCO connection with con handle 0x0002
8628     addr[5] = 0x02;
8629     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
8630     conn->con_handle = addr[5];
8631     conn->role  = HCI_ROLE_SLAVE;
8632     conn->state = RECEIVED_CONNECTION_REQUEST;
8633     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
8634 
8635     // setup ready Classic ACL connection with con handle 0x0003
8636     addr[5] = 0x03;
8637     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
8638     conn->con_handle = addr[5];
8639     conn->role  = HCI_ROLE_SLAVE;
8640     conn->state = OPEN;
8641     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
8642 
8643     // setup ready Classic SCO connection with con handle 0x0004
8644     addr[5] = 0x04;
8645     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
8646     conn->con_handle = addr[5];
8647     conn->role  = HCI_ROLE_SLAVE;
8648     conn->state = OPEN;
8649     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
8650 
8651     // setup ready LE ACL connection with con handle 0x005 and public address
8652     addr[5] = 0x05;
8653     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
8654     conn->con_handle = addr[5];
8655     conn->role  = HCI_ROLE_SLAVE;
8656     conn->state = OPEN;
8657     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
8658     conn->sm_connection.sm_connection_encrypted = 1;
8659 }
8660 
8661 void hci_free_connections_fuzz(void){
8662     btstack_linked_list_iterator_t it;
8663     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
8664     while (btstack_linked_list_iterator_has_next(&it)){
8665         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
8666         btstack_linked_list_iterator_remove(&it);
8667         btstack_memory_hci_connection_free(con);
8668     }
8669 }
8670 void hci_simulate_working_fuzz(void){
8671     hci_stack->le_scanning_param_update = false;
8672     hci_init_done();
8673     hci_stack->num_cmd_packets = 255;
8674 }
8675 #endif
8676