xref: /btstack/src/hci.c (revision f23819bcb154f0aca66b7608446a81c880404a25)
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_STATE_IDLE         0x00
115 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
116 #define GAP_INQUIRY_STATE_ACTIVE       0x81
117 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
118 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
119 
120 // GAP Remote Name Request
121 #define GAP_REMOTE_NAME_STATE_IDLE 0
122 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
123 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
124 
125 // GAP Pairing
126 #define GAP_PAIRING_STATE_IDLE                       0
127 #define GAP_PAIRING_STATE_SEND_PIN                   1
128 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
129 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
130 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
131 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
132 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
133 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
134 
135 // prototypes
136 #ifdef ENABLE_CLASSIC
137 static void hci_update_scan_enable(void);
138 static void hci_emit_discoverable_enabled(uint8_t enabled);
139 static int  hci_local_ssp_activated(void);
140 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
141 static bool hci_ssp_supported(hci_connection_t * connection);
142 static void hci_notify_if_sco_can_send_now(void);
143 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
144 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
145 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
146 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
147 static void hci_connection_timestamp(hci_connection_t *connection);
148 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
149 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
150 #endif
151 
152 static int  hci_power_control_on(void);
153 static void hci_power_control_off(void);
154 static void hci_state_reset(void);
155 static void hci_halting_timeout_handler(btstack_timer_source_t * ds);
156 static void hci_emit_transport_packet_sent(void);
157 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
158 static void hci_emit_nr_connections_changed(void);
159 static void hci_emit_hci_open_failed(void);
160 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
161 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
162 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
163 static void hci_run(void);
164 static int  hci_is_le_connection(hci_connection_t * connection);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection);
169 #endif
170 
171 #ifdef ENABLE_BLE
172 #ifdef ENABLE_LE_CENTRAL
173 // called from test/ble_client/advertising_data_parser.c
174 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
175 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
176 static void hci_whitelist_free(void);
177 static hci_connection_t * gap_get_outgoing_connection(void);
178 #endif
179 #endif
180 
181 // the STACK is here
182 #ifndef HAVE_MALLOC
183 static hci_stack_t   hci_stack_static;
184 #endif
185 static hci_stack_t * hci_stack = NULL;
186 
187 #ifdef ENABLE_CLASSIC
188 // default name
189 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
190 
191 // test helper
192 static uint8_t disable_l2cap_timeouts = 0;
193 #endif
194 
195 // reset connection state on create and on reconnect
196 // don't overwrite addr, con handle, role
197 static void hci_connection_init(hci_connection_t * conn){
198     conn->authentication_flags = AUTH_FLAG_NONE;
199     conn->bonding_flags = 0;
200     conn->requested_security_level = LEVEL_0;
201 #ifdef ENABLE_CLASSIC
202     conn->request_role = HCI_ROLE_INVALID;
203     conn->sniff_subrating_max_latency = 0xffff;
204     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
205     conn->link_key_type = INVALID_LINK_KEY;
206     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
207     btstack_run_loop_set_timer_context(&conn->timeout, conn);
208     hci_connection_timestamp(conn);
209 #endif
210     conn->acl_recombination_length = 0;
211     conn->acl_recombination_pos = 0;
212     conn->num_packets_sent = 0;
213 
214     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
215 #ifdef ENABLE_BLE
216     conn->le_phy_update_all_phys = 0xff;
217 #endif
218 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
219     conn->le_max_tx_octets = 27;
220 #endif
221 #ifdef ENABLE_CLASSIC_PAIRING_OOB
222     conn->classic_oob_c_192 = NULL;
223     conn->classic_oob_r_192 = NULL;
224     conn->classic_oob_c_256 = NULL;
225     conn->classic_oob_r_256 = NULL;
226 #endif
227 }
228 
229 /**
230  * create connection for given address
231  *
232  * @return connection OR NULL, if no memory left
233  */
234 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
235     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
236 
237     hci_connection_t * conn = btstack_memory_hci_connection_get();
238     if (!conn) return NULL;
239     hci_connection_init(conn);
240 
241     bd_addr_copy(conn->address, addr);
242     conn->address_type = addr_type;
243     conn->con_handle = HCI_CON_HANDLE_INVALID;
244     conn->role = HCI_ROLE_INVALID;
245 
246     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
247 
248     return conn;
249 }
250 
251 
252 /**
253  * get le connection parameter range
254 *
255  * @return le connection parameter range struct
256  */
257 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
258     *range = hci_stack->le_connection_parameter_range;
259 }
260 
261 /**
262  * set le connection parameter range
263  *
264  */
265 
266 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
267     hci_stack->le_connection_parameter_range = *range;
268 }
269 
270 /**
271  * @brief Test if connection parameters are inside in existing rage
272  * @param conn_interval_min (unit: 1.25ms)
273  * @param conn_interval_max (unit: 1.25ms)
274  * @param conn_latency
275  * @param supervision_timeout (unit: 10ms)
276  * @return 1 if included
277  */
278 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){
279     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
280     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
281 
282     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
283     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
284 
285     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
286     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
287 
288     return 1;
289 }
290 
291 /**
292  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
293  * @note: default: 1
294  * @param max_peripheral_connections
295  */
296 #ifdef ENABLE_LE_PERIPHERAL
297 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
298     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
299 }
300 #endif
301 
302 /**
303  * get hci connections iterator
304  *
305  * @return hci connections iterator
306  */
307 
308 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
309     btstack_linked_list_iterator_init(it, &hci_stack->connections);
310 }
311 
312 /**
313  * get connection for a given handle
314  *
315  * @return connection OR NULL, if not found
316  */
317 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
318     btstack_linked_list_iterator_t it;
319     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
320     while (btstack_linked_list_iterator_has_next(&it)){
321         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
322         if ( item->con_handle == con_handle ) {
323             return item;
324         }
325     }
326     return NULL;
327 }
328 
329 /**
330  * get connection for given address
331  *
332  * @return connection OR NULL, if not found
333  */
334 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
335     btstack_linked_list_iterator_t it;
336     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
337     while (btstack_linked_list_iterator_has_next(&it)){
338         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
339         if (connection->address_type != addr_type)  continue;
340         if (memcmp(addr, connection->address, 6) != 0) continue;
341         return connection;
342     }
343     return NULL;
344 }
345 
346 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
347     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
348 }
349 
350 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
351     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
352 }
353 
354 #ifdef ENABLE_CLASSIC
355 
356 #ifdef ENABLE_SCO_OVER_HCI
357 static int hci_number_sco_connections(void){
358     int connections = 0;
359     btstack_linked_list_iterator_t it;
360     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
361     while (btstack_linked_list_iterator_has_next(&it)){
362         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
363         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
364         connections++;
365     }
366     return connections;
367 }
368 #endif
369 
370 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
371     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
372 #ifdef HAVE_EMBEDDED_TICK
373     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
374         // connections might be timed out
375         hci_emit_l2cap_check_timeout(connection);
376     }
377 #else
378     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
379         // connections might be timed out
380         hci_emit_l2cap_check_timeout(connection);
381     }
382 #endif
383 }
384 
385 static void hci_connection_timestamp(hci_connection_t *connection){
386 #ifdef HAVE_EMBEDDED_TICK
387     connection->timestamp = btstack_run_loop_embedded_get_ticks();
388 #else
389     connection->timestamp = btstack_run_loop_get_time_ms();
390 #endif
391 }
392 
393 /**
394  * add authentication flags and reset timer
395  * @note: assumes classic connection
396  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
397  */
398 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
399     bd_addr_t addr;
400     reverse_bd_addr(bd_addr, addr);
401     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
402     if (conn) {
403         connectionSetAuthenticationFlags(conn, flags);
404         hci_connection_timestamp(conn);
405     }
406 }
407 
408 static bool hci_pairing_active(hci_connection_t * hci_connection){
409     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
410 }
411 
412 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
413     if (hci_pairing_active(hci_connection)) return;
414     if (ssp){
415         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
416     } else {
417         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
418     }
419     // if we are initiator, we have sent an HCI Authenticate Request
420     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
421 
422     // if we are responder, use minimal service security level as required level
423     if (!initiator){
424         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);
425     }
426 
427     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
428 
429     uint8_t event[12];
430     event[0] = GAP_EVENT_PAIRING_STARTED;
431     event[1] = 10;
432     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
433     reverse_bd_addr(hci_connection->address, &event[4]);
434     event[10] = (uint8_t) ssp;
435     event[11] = (uint8_t) initiator;
436     hci_emit_event(event, sizeof(event), 1);
437 }
438 
439 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
440     hci_connection->requested_security_level = LEVEL_0;
441     if (!hci_pairing_active(hci_connection)) return;
442     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
443 #ifdef ENABLE_CLASSIC_PAIRING_OOB
444     hci_connection->classic_oob_c_192 = NULL;
445     hci_connection->classic_oob_r_192 = NULL;
446     hci_connection->classic_oob_c_256 = NULL;
447     hci_connection->classic_oob_r_256 = NULL;
448 #endif
449     log_info("pairing complete, status %02x", status);
450 
451     uint8_t event[11];
452     event[0] = GAP_EVENT_PAIRING_COMPLETE;
453     event[1] = 9;
454     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
455     reverse_bd_addr(hci_connection->address, &event[4]);
456     event[10] = status;
457     hci_emit_event(event, sizeof(event), 1);
458 }
459 
460 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
461     hci_connection_t * conn = hci_connection_for_handle(handle);
462     if (!conn) return false;
463     return hci_pairing_active(conn);
464 }
465 
466 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
467     if (!hci_stack->link_key_db) return;
468     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
469     hci_stack->link_key_db->delete_link_key(addr);
470 }
471 
472 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
473     if (!hci_stack->link_key_db) return;
474     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
475     hci_stack->link_key_db->put_link_key(addr, link_key, type);
476 }
477 
478 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
479 	if (!hci_stack->link_key_db) return false;
480 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
481 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
482 	return result;
483 }
484 
485 void gap_delete_all_link_keys(void){
486     bd_addr_t  addr;
487     link_key_t link_key;
488     link_key_type_t type;
489     btstack_link_key_iterator_t it;
490     int ok = gap_link_key_iterator_init(&it);
491     if (!ok) {
492         log_error("could not initialize iterator");
493         return;
494     }
495     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
496         gap_drop_link_key_for_bd_addr(addr);
497     }
498     gap_link_key_iterator_done(&it);
499 }
500 
501 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
502     if (!hci_stack->link_key_db) return 0;
503     if (!hci_stack->link_key_db->iterator_init) return 0;
504     return hci_stack->link_key_db->iterator_init(it);
505 }
506 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){
507     if (!hci_stack->link_key_db) return 0;
508     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
509 }
510 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
511     if (!hci_stack->link_key_db) return;
512     hci_stack->link_key_db->iterator_done(it);
513 }
514 #endif
515 
516 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
517     switch (address_type){
518         case BD_ADDR_TYPE_LE_PUBLIC:
519         case BD_ADDR_TYPE_LE_RANDOM:
520         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
521         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
522             return true;
523         default:
524             return false;
525     }
526 }
527 
528 static int hci_is_le_connection(hci_connection_t * connection){
529     return hci_is_le_connection_type(connection->address_type);
530 }
531 
532 /**
533  * count connections
534  */
535 static int nr_hci_connections(void){
536     int count = 0;
537     btstack_linked_item_t *it;
538     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
539         count++;
540     }
541     return count;
542 }
543 
544 uint16_t hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
545 
546     unsigned int num_packets_sent_classic = 0;
547     unsigned int num_packets_sent_le = 0;
548 
549     btstack_linked_item_t *it;
550     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
551         hci_connection_t * connection = (hci_connection_t *) it;
552         if (hci_is_le_connection(connection)){
553             num_packets_sent_le += connection->num_packets_sent;
554         }
555         if (connection->address_type == BD_ADDR_TYPE_ACL){
556             num_packets_sent_classic += connection->num_packets_sent;
557         }
558     }
559     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
560     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
561     int free_slots_le = 0;
562 
563     if (free_slots_classic < 0){
564         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);
565         return 0;
566     }
567 
568     if (hci_stack->le_acl_packets_total_num){
569         // if we have LE slots, they are used
570         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
571         if (free_slots_le < 0){
572             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);
573             return 0;
574         }
575     } else {
576         // otherwise, classic slots are used for LE, too
577         free_slots_classic -= num_packets_sent_le;
578         if (free_slots_classic < 0){
579             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);
580             return 0;
581         }
582     }
583 
584     switch (address_type){
585         case BD_ADDR_TYPE_UNKNOWN:
586             log_error("hci_number_free_acl_slots: unknown address type");
587             return 0;
588 
589         case BD_ADDR_TYPE_ACL:
590             return (uint16_t) free_slots_classic;
591 
592         default:
593            if (hci_stack->le_acl_packets_total_num > 0){
594                return (uint16_t) free_slots_le;
595            }
596            return (uint16_t) free_slots_classic;
597     }
598 }
599 
600 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
601     // get connection type
602     hci_connection_t * connection = hci_connection_for_handle(con_handle);
603     if (!connection){
604         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
605         return 0;
606     }
607     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
608 }
609 
610 #ifdef ENABLE_CLASSIC
611 static int hci_number_free_sco_slots(void){
612     unsigned int num_sco_packets_sent  = 0;
613     btstack_linked_item_t *it;
614     if (hci_stack->synchronous_flow_control_enabled){
615         // explicit flow control
616         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
617             hci_connection_t * connection = (hci_connection_t *) it;
618             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
619             num_sco_packets_sent += connection->num_packets_sent;
620         }
621         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
622             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
623             return 0;
624         }
625         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
626     } else {
627         // implicit flow control -- TODO
628         int num_ready = 0;
629         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
630             hci_connection_t * connection = (hci_connection_t *) it;
631             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
632             if (connection->sco_tx_ready == 0) continue;
633             num_ready++;
634         }
635         return num_ready;
636     }
637 }
638 #endif
639 
640 // only used to send HCI Host Number Completed Packets
641 static int hci_can_send_comand_packet_transport(void){
642     if (hci_stack->hci_packet_buffer_reserved) return 0;
643 
644     // check for async hci transport implementations
645     if (hci_stack->hci_transport->can_send_packet_now){
646         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
647             return 0;
648         }
649     }
650     return 1;
651 }
652 
653 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
654 bool hci_can_send_command_packet_now(void){
655     if (hci_can_send_comand_packet_transport() == 0) return false;
656     return hci_stack->num_cmd_packets > 0u;
657 }
658 
659 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
660     // check for async hci transport implementations
661     if (!hci_stack->hci_transport->can_send_packet_now) return true;
662     return hci_stack->hci_transport->can_send_packet_now(packet_type);
663 }
664 
665 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
666     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
667     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
668 }
669 
670 bool hci_can_send_acl_le_packet_now(void){
671     if (hci_stack->hci_packet_buffer_reserved) return false;
672     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
673 }
674 
675 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
676     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
677     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
678 }
679 
680 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
681     if (hci_stack->hci_packet_buffer_reserved) return false;
682     return hci_can_send_prepared_acl_packet_now(con_handle);
683 }
684 
685 #ifdef ENABLE_CLASSIC
686 bool hci_can_send_acl_classic_packet_now(void){
687     if (hci_stack->hci_packet_buffer_reserved) return false;
688     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
689 }
690 
691 bool hci_can_send_prepared_sco_packet_now(void){
692     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
693     if (hci_have_usb_transport()){
694         return hci_stack->sco_can_send_now;
695     } else {
696         return hci_number_free_sco_slots() > 0;
697     }
698 }
699 
700 bool hci_can_send_sco_packet_now(void){
701     if (hci_stack->hci_packet_buffer_reserved) return false;
702     return hci_can_send_prepared_sco_packet_now();
703 }
704 
705 void hci_request_sco_can_send_now_event(void){
706     hci_stack->sco_waiting_for_can_send_now = 1;
707     hci_notify_if_sco_can_send_now();
708 }
709 #endif
710 
711 // used for internal checks in l2cap.c
712 bool hci_is_packet_buffer_reserved(void){
713     return hci_stack->hci_packet_buffer_reserved;
714 }
715 
716 // reserves outgoing packet buffer.
717 // @return 1 if successful
718 bool hci_reserve_packet_buffer(void){
719     if (hci_stack->hci_packet_buffer_reserved) {
720         log_error("hci_reserve_packet_buffer called but buffer already reserved");
721         return false;
722     }
723     hci_stack->hci_packet_buffer_reserved = true;
724     return true;
725 }
726 
727 void hci_release_packet_buffer(void){
728     hci_stack->hci_packet_buffer_reserved = false;
729 }
730 
731 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
732 static int hci_transport_synchronous(void){
733     return hci_stack->hci_transport->can_send_packet_now == NULL;
734 }
735 
736 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
737 
738     // 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);
739 
740     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
741     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
742     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
743         max_acl_data_packet_length = hci_stack->le_data_packets_length;
744     }
745 
746 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
747     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
748         max_acl_data_packet_length = connection->le_max_tx_octets;
749     }
750 #endif
751 
752     log_debug("hci_send_acl_packet_fragments entered");
753 
754     uint8_t status = ERROR_CODE_SUCCESS;
755     // multiple packets could be send on a synchronous HCI transport
756     while (true){
757 
758         log_debug("hci_send_acl_packet_fragments loop entered");
759 
760         // get current data
761         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
762         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
763         bool more_fragments = false;
764 
765         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
766         if (current_acl_data_packet_length > max_acl_data_packet_length){
767             more_fragments = true;
768             current_acl_data_packet_length = max_acl_data_packet_length;
769         }
770 
771         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
772         if (acl_header_pos > 0u){
773             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
774             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
775             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
776         }
777 
778         // update header len
779         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
780 
781         // count packet
782         connection->num_packets_sent++;
783         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
784 
785         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
786         if (more_fragments){
787             // update start of next fragment to send
788             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
789         } else {
790             // done
791             hci_stack->acl_fragmentation_pos = 0;
792             hci_stack->acl_fragmentation_total_size = 0;
793         }
794 
795         // send packet
796         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
797         const int size = current_acl_data_packet_length + 4;
798         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
799         hci_stack->acl_fragmentation_tx_active = 1;
800         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
801         if (err != 0){
802             // no error from HCI Transport expected
803             status = ERROR_CODE_HARDWARE_FAILURE;
804         }
805 
806         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
807 
808         // done yet?
809         if (!more_fragments) break;
810 
811         // can send more?
812         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
813     }
814 
815     log_debug("hci_send_acl_packet_fragments loop over");
816 
817     // release buffer now for synchronous transport
818     if (hci_transport_synchronous()){
819         hci_stack->acl_fragmentation_tx_active = 0;
820         hci_release_packet_buffer();
821         hci_emit_transport_packet_sent();
822     }
823 
824     return status;
825 }
826 
827 // pre: caller has reserved the packet buffer
828 uint8_t hci_send_acl_packet_buffer(int size){
829     btstack_assert(hci_stack->hci_packet_buffer_reserved);
830 
831     uint8_t * packet = hci_stack->hci_packet_buffer;
832     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
833 
834     // check for free places on Bluetooth module
835     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
836         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
837         hci_release_packet_buffer();
838         hci_emit_transport_packet_sent();
839         return BTSTACK_ACL_BUFFERS_FULL;
840     }
841 
842     hci_connection_t *connection = hci_connection_for_handle( con_handle);
843     if (!connection) {
844         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
845         hci_release_packet_buffer();
846         hci_emit_transport_packet_sent();
847         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
848     }
849 
850 #ifdef ENABLE_CLASSIC
851     hci_connection_timestamp(connection);
852 #endif
853 
854     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
855 
856     // setup data
857     hci_stack->acl_fragmentation_total_size = size;
858     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
859 
860     return hci_send_acl_packet_fragments(connection);
861 }
862 
863 #ifdef ENABLE_CLASSIC
864 // pre: caller has reserved the packet buffer
865 uint8_t hci_send_sco_packet_buffer(int size){
866     btstack_assert(hci_stack->hci_packet_buffer_reserved);
867 
868     uint8_t * packet = hci_stack->hci_packet_buffer;
869 
870     // skip checks in loopback mode
871     if (!hci_stack->loopback_mode){
872         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
873 
874         // check for free places on Bluetooth module
875         if (!hci_can_send_prepared_sco_packet_now()) {
876             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
877             hci_release_packet_buffer();
878             hci_emit_transport_packet_sent();
879             return BTSTACK_ACL_BUFFERS_FULL;
880         }
881 
882         // track send packet in connection struct
883         hci_connection_t *connection = hci_connection_for_handle( con_handle);
884         if (!connection) {
885             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
886             hci_release_packet_buffer();
887             hci_emit_transport_packet_sent();
888             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
889         }
890 
891         if (hci_have_usb_transport()){
892             // token used
893             hci_stack->sco_can_send_now = false;
894         } else {
895             if (hci_stack->synchronous_flow_control_enabled){
896                 connection->num_packets_sent++;
897             } else {
898                 connection->sco_tx_ready--;
899             }
900         }
901     }
902 
903     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
904 
905 #ifdef HAVE_SCO_TRANSPORT
906     hci_stack->sco_transport->send_packet(packet, size);
907     hci_release_packet_buffer();
908     hci_emit_transport_packet_sent();
909 
910     return 0;
911 #else
912     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
913     if (hci_transport_synchronous()){
914         hci_release_packet_buffer();
915         hci_emit_transport_packet_sent();
916     }
917 
918     if (err != 0){
919         return ERROR_CODE_HARDWARE_FAILURE;
920     }
921     return ERROR_CODE_SUCCESS;
922 #endif
923 }
924 #endif
925 
926 static void acl_handler(uint8_t *packet, uint16_t size){
927 
928     // get info
929     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
930     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
931     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
932     uint16_t acl_length         = READ_ACL_LENGTH(packet);
933 
934     // ignore non-registered handle
935     if (!conn){
936         log_error("acl_handler called with non-registered handle %u!" , con_handle);
937         return;
938     }
939 
940     // assert packet is complete
941     if ((acl_length + 4u) != size){
942         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
943         return;
944     }
945 
946 #ifdef ENABLE_CLASSIC
947     // update idle timestamp
948     hci_connection_timestamp(conn);
949 #endif
950 
951 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
952     hci_stack->host_completed_packets = 1;
953     conn->num_packets_completed++;
954 #endif
955 
956     // handle different packet types
957     switch (acl_flags & 0x03u) {
958 
959         case 0x01: // continuation fragment
960 
961             // sanity checks
962             if (conn->acl_recombination_pos == 0u) {
963                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
964                 return;
965             }
966             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
967                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
968                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
969                 conn->acl_recombination_pos = 0;
970                 return;
971             }
972 
973             // append fragment payload (header already stored)
974             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
975                          &packet[4], acl_length);
976             conn->acl_recombination_pos += acl_length;
977 
978             // forward complete L2CAP packet if complete.
979             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
980                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
981                 // reset recombination buffer
982                 conn->acl_recombination_length = 0;
983                 conn->acl_recombination_pos = 0;
984             }
985             break;
986 
987         case 0x02: { // first fragment
988 
989             // sanity check
990             if (conn->acl_recombination_pos) {
991                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
992                 conn->acl_recombination_pos = 0;
993             }
994 
995             // peek into L2CAP packet!
996             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
997 
998             // compare fragment size to L2CAP packet size
999             if (acl_length >= (l2cap_length + 4u)){
1000                 // forward fragment as L2CAP packet
1001                 hci_emit_acl_packet(packet, acl_length + 4u);
1002             } else {
1003 
1004                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1005                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1006                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1007                     return;
1008                 }
1009 
1010                 // store first fragment and tweak acl length for complete package
1011                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1012                              packet, acl_length + 4u);
1013                 conn->acl_recombination_pos    = acl_length + 4u;
1014                 conn->acl_recombination_length = l2cap_length;
1015                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1016             }
1017             break;
1018 
1019         }
1020         default:
1021             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1022             return;
1023     }
1024 
1025     // execute main loop
1026     hci_run();
1027 }
1028 
1029 static void hci_connection_stop_timer(hci_connection_t * conn){
1030     btstack_run_loop_remove_timer(&conn->timeout);
1031 #ifdef ENABLE_CLASSIC
1032     btstack_run_loop_remove_timer(&conn->timeout_sco);
1033 #endif
1034 }
1035 
1036 static void hci_shutdown_connection(hci_connection_t *conn){
1037     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1038 
1039 #ifdef ENABLE_CLASSIC
1040 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1041     bd_addr_type_t addr_type = conn->address_type;
1042 #endif
1043 #ifdef HAVE_SCO_TRANSPORT
1044     hci_con_handle_t con_handle = conn->con_handle;
1045 #endif
1046 #endif
1047 
1048     hci_connection_stop_timer(conn);
1049 
1050     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1051     btstack_memory_hci_connection_free( conn );
1052 
1053     // now it's gone
1054     hci_emit_nr_connections_changed();
1055 
1056 #ifdef ENABLE_CLASSIC
1057 #ifdef ENABLE_SCO_OVER_HCI
1058     // update SCO
1059     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1060         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1061     }
1062 #endif
1063 #ifdef HAVE_SCO_TRANSPORT
1064     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1065         hci_stack->sco_transport->close(con_handle);
1066     }
1067 #endif
1068 #endif
1069 }
1070 
1071 #ifdef ENABLE_CLASSIC
1072 
1073 static const uint16_t packet_type_sizes[] = {
1074     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1075     HCI_ACL_DH1_SIZE, 0, 0, 0,
1076     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1077     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1078 };
1079 static const uint8_t  packet_type_feature_requirement_bit[] = {
1080      0, // 3 slot packets
1081      1, // 5 slot packets
1082     25, // EDR 2 mpbs
1083     26, // EDR 3 mbps
1084     39, // 3 slot EDR packts
1085     40, // 5 slot EDR packet
1086 };
1087 static const uint16_t packet_type_feature_packet_mask[] = {
1088     0x0f00, // 3 slot packets
1089     0xf000, // 5 slot packets
1090     0x1102, // EDR 2 mpbs
1091     0x2204, // EDR 3 mbps
1092     0x0300, // 3 slot EDR packts
1093     0x3000, // 5 slot EDR packet
1094 };
1095 
1096 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1097     // enable packet types based on size
1098     uint16_t packet_types = 0;
1099     unsigned int i;
1100     for (i=0;i<16;i++){
1101         if (packet_type_sizes[i] == 0) continue;
1102         if (packet_type_sizes[i] <= buffer_size){
1103             packet_types |= 1 << i;
1104         }
1105     }
1106     // disable packet types due to missing local supported features
1107     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1108         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1109         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1110         if (feature_set) continue;
1111         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1112         packet_types &= ~packet_type_feature_packet_mask[i];
1113     }
1114     // flip bits for "may not be used"
1115     packet_types ^= 0x3306;
1116     return packet_types;
1117 }
1118 
1119 uint16_t hci_usable_acl_packet_types(void){
1120     return hci_stack->packet_types;
1121 }
1122 #endif
1123 
1124 uint8_t* hci_get_outgoing_packet_buffer(void){
1125     // hci packet buffer is >= acl data packet length
1126     return hci_stack->hci_packet_buffer;
1127 }
1128 
1129 uint16_t hci_max_acl_data_packet_length(void){
1130     return hci_stack->acl_data_packet_length;
1131 }
1132 
1133 #ifdef ENABLE_CLASSIC
1134 bool hci_extended_sco_link_supported(void){
1135     // No. 31, byte 3, bit 7
1136     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1137 }
1138 #endif
1139 
1140 bool hci_non_flushable_packet_boundary_flag_supported(void){
1141     // No. 54, byte 6, bit 6
1142     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1143 }
1144 
1145 #ifdef ENABLE_CLASSIC
1146 static int gap_ssp_supported(void){
1147     // No. 51, byte 6, bit 3
1148     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1149 }
1150 #endif
1151 
1152 static int hci_classic_supported(void){
1153 #ifdef ENABLE_CLASSIC
1154     // No. 37, byte 4, bit 5, = No BR/EDR Support
1155     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1156 #else
1157     return 0;
1158 #endif
1159 }
1160 
1161 static int hci_le_supported(void){
1162 #ifdef ENABLE_BLE
1163     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1164     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1165 #else
1166     return 0;
1167 #endif
1168 }
1169 
1170 #ifdef ENABLE_BLE
1171 
1172 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1173     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1174         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1175     } else {
1176         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1177     }
1178 }
1179 
1180 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1181     *addr_type = hci_stack->le_own_addr_type;
1182     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1183 }
1184 
1185 #ifdef ENABLE_LE_PERIPHERAL
1186 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1187     *addr_type = hci_stack->le_advertisements_own_addr_type;
1188     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1189 };
1190 #endif
1191 
1192 #ifdef ENABLE_LE_CENTRAL
1193 
1194 /**
1195  * @brief Get own addr type and address used for LE connections (Central)
1196  */
1197 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1198     *addr_type = hci_stack->le_connection_own_addr_type;
1199     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1200 }
1201 
1202 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1203 
1204     int offset = 3;
1205     int num_reports = packet[offset];
1206     offset += 1;
1207 
1208     int i;
1209     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1210     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1211     for (i=0; (i<num_reports) && (offset < size);i++){
1212         // sanity checks on data_length:
1213         uint8_t data_length = packet[offset + 8];
1214         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1215         if ((offset + 9u + data_length + 1u) > size)    return;
1216         // setup event
1217         uint8_t event_size = 10u + data_length;
1218         int pos = 0;
1219         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1220         event[pos++] = event_size;
1221         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1222         offset += 8;
1223         pos += 8;
1224         event[pos++] = packet[offset + 1 + data_length]; // rssi
1225         event[pos++] = data_length;
1226         offset++;
1227         (void)memcpy(&event[pos], &packet[offset], data_length);
1228         pos +=    data_length;
1229         offset += data_length + 1u; // rssi
1230         hci_emit_event(event, pos, 1);
1231     }
1232 }
1233 #endif
1234 #endif
1235 
1236 #ifdef ENABLE_BLE
1237 #ifdef ENABLE_LE_PERIPHERAL
1238 static void hci_update_advertisements_enabled_for_current_roles(void){
1239     if (hci_stack->le_advertisements_enabled){
1240         // get number of active le slave connections
1241         int num_slave_connections = 0;
1242         btstack_linked_list_iterator_t it;
1243         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1244         while (btstack_linked_list_iterator_has_next(&it)){
1245             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1246             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1247             if (con->state != OPEN) continue;
1248             if (con->role  != HCI_ROLE_SLAVE) continue;
1249             if (!hci_is_le_connection(con)) continue;
1250             num_slave_connections++;
1251         }
1252         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1253         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1254     } else {
1255         hci_stack->le_advertisements_enabled_for_current_roles = false;
1256     }
1257 }
1258 #endif
1259 #endif
1260 
1261 #ifdef ENABLE_CLASSIC
1262 static void gap_run_set_local_name(void){
1263     hci_reserve_packet_buffer();
1264     uint8_t * packet = hci_stack->hci_packet_buffer;
1265     // construct HCI Command and send
1266     uint16_t opcode = hci_write_local_name.opcode;
1267     hci_stack->last_cmd_opcode = opcode;
1268     packet[0] = opcode & 0xff;
1269     packet[1] = opcode >> 8;
1270     packet[2] = DEVICE_NAME_LEN;
1271     memset(&packet[3], 0, DEVICE_NAME_LEN);
1272     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1273     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1274     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1275     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1276     // expand '00:00:00:00:00:00' in name with bd_addr
1277     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1278     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1279 }
1280 
1281 static void gap_run_set_eir_data(void){
1282     hci_reserve_packet_buffer();
1283     uint8_t * packet = hci_stack->hci_packet_buffer;
1284     // construct HCI Command in-place and send
1285     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1286     hci_stack->last_cmd_opcode = opcode;
1287     uint16_t offset = 0;
1288     packet[offset++] = opcode & 0xff;
1289     packet[offset++] = opcode >> 8;
1290     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1291     packet[offset++] = 0;  // FEC not required
1292     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1293     if (hci_stack->eir_data){
1294         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1295         ad_context_t context;
1296         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1297             uint8_t data_type   = ad_iterator_get_data_type(&context);
1298             uint8_t size        = ad_iterator_get_data_len(&context);
1299             const uint8_t *data = ad_iterator_get_data(&context);
1300             // copy item
1301             packet[offset++] = size + 1;
1302             packet[offset++] = data_type;
1303             memcpy(&packet[offset], data, size);
1304             // update name item
1305             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1306                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1307             }
1308             offset += size;
1309         }
1310     } else {
1311         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1312         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1313         packet[offset++] = bytes_to_copy + 1;
1314         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1315         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1316         // expand '00:00:00:00:00:00' in name with bd_addr
1317         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1318     }
1319     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1320 }
1321 
1322 static void hci_run_gap_tasks_classic(void){
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1325         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1330         gap_run_set_local_name();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1335         gap_run_set_eir_data();
1336         return;
1337     }
1338     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1339         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1340         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1341         return;
1342     }
1343     // write page scan activity
1344     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1345         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1346         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1347         return;
1348     }
1349     // write page scan type
1350     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1351         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1352         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1353         return;
1354     }
1355     // write page timeout
1356     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_TIMEOUT) != 0) {
1357         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_TIMEOUT;
1358         hci_send_cmd(&hci_write_page_timeout, hci_stack->page_timeout);
1359         return;
1360     }
1361     // send scan enable
1362     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1363         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1364         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1365         return;
1366     }
1367     // send write scan activity
1368     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY) != 0) {
1369         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
1370         hci_send_cmd(&hci_write_inquiry_scan_activity, hci_stack->inquiry_scan_interval, hci_stack->inquiry_scan_window);
1371         return;
1372     }
1373 }
1374 #endif
1375 
1376 #ifndef HAVE_HOST_CONTROLLER_API
1377 
1378 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1379     if (!hci_stack->config) return 0;
1380     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1381     // Limit baud rate for Broadcom chipsets to 3 mbps
1382     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1383         baud_rate = 3000000;
1384     }
1385     return baud_rate;
1386 }
1387 
1388 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1389     UNUSED(ds);
1390 
1391     switch (hci_stack->substate){
1392         case HCI_INIT_W4_SEND_RESET:
1393             log_info("Resend HCI Reset");
1394             hci_stack->substate = HCI_INIT_SEND_RESET;
1395             hci_stack->num_cmd_packets = 1;
1396             hci_run();
1397             break;
1398         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1399             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1400             if (hci_stack->hci_transport->reset_link){
1401                 hci_stack->hci_transport->reset_link();
1402             }
1403 
1404             /* fall through */
1405 
1406         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1407             log_info("Resend HCI Reset - CSR Warm Boot");
1408             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1409             hci_stack->num_cmd_packets = 1;
1410             hci_run();
1411             break;
1412         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1413             if (hci_stack->hci_transport->set_baudrate){
1414                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1415                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1416                 hci_stack->hci_transport->set_baudrate(baud_rate);
1417             }
1418             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1419             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1420                 if (hci_stack->hci_transport->reset_link){
1421                     log_info("Link Reset");
1422                     hci_stack->hci_transport->reset_link();
1423                 }
1424                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1425                 hci_run();
1426             }
1427             break;
1428         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1429             // otherwise continue
1430             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1431             hci_send_cmd(&hci_read_local_supported_commands);
1432             break;
1433         default:
1434             break;
1435     }
1436 }
1437 #endif
1438 
1439 static void hci_initializing_next_state(void){
1440     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1441 }
1442 
1443 static void hci_init_done(void){
1444     // done. tell the app
1445     log_info("hci_init_done -> HCI_STATE_WORKING");
1446     hci_stack->state = HCI_STATE_WORKING;
1447     hci_emit_state();
1448 }
1449 
1450 // assumption: hci_can_send_command_packet_now() == true
1451 static void hci_initializing_run(void){
1452     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1453 
1454     if (!hci_can_send_command_packet_now()) return;
1455 
1456 #ifndef HAVE_HOST_CONTROLLER_API
1457     bool need_baud_change = hci_stack->config
1458             && hci_stack->chipset
1459             && hci_stack->chipset->set_baudrate_command
1460             && hci_stack->hci_transport->set_baudrate
1461             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1462 #endif
1463 
1464     switch (hci_stack->substate){
1465         case HCI_INIT_SEND_RESET:
1466             hci_state_reset();
1467 
1468 #ifndef HAVE_HOST_CONTROLLER_API
1469             // prepare reset if command complete not received in 100ms
1470             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1471             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1472             btstack_run_loop_add_timer(&hci_stack->timeout);
1473 #endif
1474             // send command
1475             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1476             hci_send_cmd(&hci_reset);
1477             break;
1478         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1479             hci_send_cmd(&hci_read_local_version_information);
1480             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1481             break;
1482 
1483 #ifndef HAVE_HOST_CONTROLLER_API
1484         case HCI_INIT_SEND_READ_LOCAL_NAME:
1485             hci_send_cmd(&hci_read_local_name);
1486             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1487             break;
1488         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1489             hci_state_reset();
1490             // prepare reset if command complete not received in 100ms
1491             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1492             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1493             btstack_run_loop_add_timer(&hci_stack->timeout);
1494             // send command
1495             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1496             hci_send_cmd(&hci_reset);
1497             break;
1498         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1499             hci_state_reset();
1500             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1501             hci_send_cmd(&hci_reset);
1502             break;
1503         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1504             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1505             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1506             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1507             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1508             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1509             break;
1510         }
1511         case HCI_INIT_SET_BD_ADDR:
1512             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1513             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1514             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1515             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1516             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1517             break;
1518         case HCI_INIT_SEND_BAUD_CHANGE:
1519             if (need_baud_change) {
1520                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1521                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1522                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1523                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1524                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1525                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1526                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1527                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1528                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1529                     btstack_run_loop_add_timer(&hci_stack->timeout);
1530                }
1531                break;
1532             }
1533 
1534             /* fall through */
1535 
1536         case HCI_INIT_CUSTOM_INIT:
1537             // Custom initialization
1538             if (hci_stack->chipset && hci_stack->chipset->next_command){
1539                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1540                 bool send_cmd = false;
1541                 switch (hci_stack->chipset_result){
1542                     case BTSTACK_CHIPSET_VALID_COMMAND:
1543                         send_cmd = true;
1544                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1545                         break;
1546                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1547                         send_cmd = true;
1548                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1549                         log_info("CSR Warm Boot");
1550                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1551                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1552                         btstack_run_loop_add_timer(&hci_stack->timeout);
1553                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1554                             && hci_stack->config
1555                             && hci_stack->chipset
1556                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1557                             && hci_stack->hci_transport->set_baudrate
1558                             && hci_transport_uart_get_main_baud_rate()){
1559                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1560                         } else {
1561                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1562                         }
1563                         break;
1564                     default:
1565                         break;
1566                 }
1567 
1568                 if (send_cmd){
1569                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1570                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1571                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1572                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1573                     break;
1574                 }
1575                 log_info("Init script done");
1576 
1577                 // Init script download on Broadcom chipsets causes:
1578                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1579                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1580                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1581 
1582                     // - baud rate to reset, restore UART baud rate if needed
1583                     if (need_baud_change) {
1584                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1585                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1586                         hci_stack->hci_transport->set_baudrate(baud_rate);
1587                     }
1588 
1589                     uint16_t bcm_delay_ms = 300;
1590                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1591                     //   -> Work around: wait here.
1592                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1593                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1594                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1595                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1596                     btstack_run_loop_add_timer(&hci_stack->timeout);
1597                     break;
1598                 }
1599             }
1600 #endif
1601             /* fall through */
1602 
1603         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1604             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1605             hci_send_cmd(&hci_read_local_supported_commands);
1606             break;
1607         case HCI_INIT_READ_BD_ADDR:
1608             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1609             hci_send_cmd(&hci_read_bd_addr);
1610             break;
1611         case HCI_INIT_READ_BUFFER_SIZE:
1612             // only read buffer size if supported
1613             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1614                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1615                 hci_send_cmd(&hci_read_buffer_size);
1616                 break;
1617             }
1618 
1619             /* fall through */
1620 
1621         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1622             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1623             hci_send_cmd(&hci_read_local_supported_features);
1624             break;
1625 
1626 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1627         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1628             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1629             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1630             break;
1631         case HCI_INIT_HOST_BUFFER_SIZE:
1632             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1633             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1634                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1635             break;
1636 #endif
1637 
1638         case HCI_INIT_SET_EVENT_MASK:
1639             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1640             if (hci_le_supported()){
1641                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1642             } else {
1643                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1644                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1645             }
1646             break;
1647 
1648 #ifdef ENABLE_CLASSIC
1649         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1650             if (hci_classic_supported() && gap_ssp_supported()){
1651                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1652                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1653                 break;
1654             }
1655 
1656             /* fall through */
1657 
1658         case HCI_INIT_WRITE_INQUIRY_MODE:
1659             if (hci_classic_supported()){
1660                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1661                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1662                 break;
1663             }
1664 
1665             /* fall through */
1666 
1667         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1668             // skip write secure connections host support if not supported or disabled
1669             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1670                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1671                 hci_stack->secure_connections_active = true;
1672                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1673                 break;
1674             }
1675 
1676 #ifdef ENABLE_SCO_OVER_HCI
1677             /* fall through */
1678 
1679         // only sent if ENABLE_SCO_OVER_HCI is defined
1680         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1681             // skip write synchronous flow control if not supported
1682             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1683                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1684                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1685                 break;
1686             }
1687             /* fall through */
1688 
1689         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1690             // skip write default erroneous data reporting if not supported
1691             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1692                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1693                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1694                 break;
1695             }
1696 #endif
1697 
1698 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1699             /* fall through */
1700 
1701         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1702         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1703             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1704                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1705 #ifdef ENABLE_SCO_OVER_HCI
1706                 log_info("BCM: Route SCO data via HCI transport");
1707                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1708 #endif
1709 #ifdef ENABLE_SCO_OVER_PCM
1710                 log_info("BCM: Route SCO data via PCM interface");
1711 #ifdef ENABLE_BCM_PCM_WBS
1712                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1713                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1714 #else
1715                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1716                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1717 #endif
1718 #endif
1719                 break;
1720             }
1721 #endif
1722 
1723 #ifdef ENABLE_SCO_OVER_PCM
1724             /* fall through */
1725 
1726         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1727             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1728                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1729                 log_info("BCM: Config PCM interface for I2S");
1730 #ifdef ENABLE_BCM_PCM_WBS
1731                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1732                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1733 #else
1734                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1735                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1736 #endif
1737                 break;
1738             }
1739 #endif
1740 #endif
1741 
1742 #ifdef ENABLE_BLE
1743             /* fall through */
1744 
1745         // LE INIT
1746         case HCI_INIT_LE_READ_BUFFER_SIZE:
1747             if (hci_le_supported()){
1748                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1749                 hci_send_cmd(&hci_le_read_buffer_size);
1750                 break;
1751             }
1752 
1753             /* fall through */
1754 
1755         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1756             // skip write le host if not supported (e.g. on LE only EM9301)
1757             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1758                 // LE Supported Host = 1, Simultaneous Host = 0
1759                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1760                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1761                 break;
1762             }
1763 
1764             /* fall through */
1765 
1766         case HCI_INIT_LE_SET_EVENT_MASK:
1767             if (hci_le_supported()){
1768                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1769                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1770                 break;
1771             }
1772 #endif
1773 
1774 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1775             /* fall through */
1776 
1777         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1778             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1779                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1780                 hci_send_cmd(&hci_le_read_maximum_data_length);
1781                 break;
1782             }
1783 
1784             /* fall through */
1785 
1786         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1787             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1788                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1789                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1790                 break;
1791             }
1792 #endif
1793 
1794 #ifdef ENABLE_LE_CENTRAL
1795             /* fall through */
1796 
1797         case HCI_INIT_READ_WHITE_LIST_SIZE:
1798             if (hci_le_supported()){
1799                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1800                 hci_send_cmd(&hci_le_read_white_list_size);
1801                 break;
1802             }
1803 
1804             /* fall through */
1805 
1806         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1807             if (hci_le_supported()){
1808                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1809                 hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
1810                 break;
1811             }
1812 #endif
1813 
1814             /* fall through */
1815 
1816         case HCI_INIT_DONE:
1817             hci_stack->substate = HCI_INIT_DONE;
1818 #ifdef ENABLE_CLASSIC
1819             // init sequence complete, check if GAP Tasks are completed
1820             if (hci_stack->gap_tasks != 0) {
1821                 hci_run_gap_tasks_classic();
1822                 break;
1823             }
1824 #endif
1825             hci_init_done();
1826             break;
1827 
1828         default:
1829             return;
1830     }
1831 }
1832 
1833 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1834     bool command_completed = false;
1835     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1836         uint16_t opcode = little_endian_read_16(packet,3);
1837         if (opcode == hci_stack->last_cmd_opcode){
1838             command_completed = true;
1839             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1840         } else {
1841             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1842         }
1843     }
1844 
1845     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1846         uint8_t  status = packet[2];
1847         uint16_t opcode = little_endian_read_16(packet,4);
1848         if (opcode == hci_stack->last_cmd_opcode){
1849             if (status){
1850                 command_completed = true;
1851                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1852             } else {
1853                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1854             }
1855         } else {
1856             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1857         }
1858     }
1859 #ifndef HAVE_HOST_CONTROLLER_API
1860     // Vendor == CSR
1861     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1862         // TODO: track actual command
1863         command_completed = true;
1864     }
1865 
1866     // Vendor == Toshiba
1867     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1868         // TODO: track actual command
1869         command_completed = true;
1870         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1871         hci_stack->num_cmd_packets = 1;
1872     }
1873 #endif
1874 
1875     return command_completed;
1876 }
1877 
1878 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1879 
1880     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1881 
1882     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1883 
1884 #ifndef HAVE_HOST_CONTROLLER_API
1885 
1886     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1887     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1888     //
1889     // HCI Reset
1890     // Timeout 100 ms
1891     // HCI Reset
1892     // Command Complete Reset
1893     // HCI Read Local Version Information
1894     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1895     // hang...
1896     //
1897     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1898     if (!command_completed
1899             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1900             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1901 
1902         uint16_t opcode = little_endian_read_16(packet,3);
1903         if (opcode == hci_reset.opcode){
1904             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1905             return;
1906         }
1907     }
1908 
1909     // CSR & H5
1910     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1911     if (!command_completed
1912             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1913             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1914 
1915         uint16_t opcode = little_endian_read_16(packet,3);
1916         if (opcode == hci_reset.opcode){
1917             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1918             return;
1919         }
1920     }
1921 
1922     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1923     // fix: Correct substate and behave as command below
1924     if (command_completed){
1925         switch (hci_stack->substate){
1926             case HCI_INIT_SEND_RESET:
1927                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1928                 break;
1929             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1930                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1931                 break;
1932             default:
1933                 break;
1934         }
1935     }
1936 
1937 #endif
1938 
1939     if (!command_completed) return;
1940 
1941     bool need_baud_change = false;
1942     bool need_addr_change = false;
1943 
1944 #ifndef HAVE_HOST_CONTROLLER_API
1945     need_baud_change = hci_stack->config
1946                         && hci_stack->chipset
1947                         && hci_stack->chipset->set_baudrate_command
1948                         && hci_stack->hci_transport->set_baudrate
1949                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1950 
1951     need_addr_change = hci_stack->custom_bd_addr_set
1952                         && hci_stack->chipset
1953                         && hci_stack->chipset->set_bd_addr_command;
1954 #endif
1955 
1956     switch(hci_stack->substate){
1957 
1958 #ifndef HAVE_HOST_CONTROLLER_API
1959         case HCI_INIT_SEND_RESET:
1960             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1961             // fix: just correct substate and behave as command below
1962 
1963             /* fall through */
1964 #endif
1965 
1966         case HCI_INIT_W4_SEND_RESET:
1967             btstack_run_loop_remove_timer(&hci_stack->timeout);
1968             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1969             return;
1970 
1971 #ifndef HAVE_HOST_CONTROLLER_API
1972         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1973             // for STLC2500D, baud rate change already happened.
1974             // for others, baud rate gets changed now
1975             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1976                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1977                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1978                 hci_stack->hci_transport->set_baudrate(baud_rate);
1979             }
1980             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1981             return;
1982         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1983             btstack_run_loop_remove_timer(&hci_stack->timeout);
1984             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1985             return;
1986         case HCI_INIT_W4_CUSTOM_INIT:
1987             // repeat custom init
1988             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1989             return;
1990 #endif
1991 
1992         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1993             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1994               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1995                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1996                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1997                 return;
1998             }
1999             if (need_addr_change){
2000                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2001                 return;
2002             }
2003             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2004             return;
2005 #ifndef HAVE_HOST_CONTROLLER_API
2006         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
2007             if (need_baud_change){
2008                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
2009                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
2010                 hci_stack->hci_transport->set_baudrate(baud_rate);
2011             }
2012             if (need_addr_change){
2013                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2014                 return;
2015             }
2016             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2017             return;
2018         case HCI_INIT_W4_SET_BD_ADDR:
2019             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
2020             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
2021             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2022                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2023                 return;
2024             }
2025             // skipping st warm boot
2026             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2027             return;
2028         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2029             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2030             return;
2031 #endif
2032 
2033         case HCI_INIT_DONE:
2034             // set state if we came here by fall through
2035             hci_stack->substate = HCI_INIT_DONE;
2036             return;
2037 
2038         default:
2039             break;
2040     }
2041     hci_initializing_next_state();
2042 }
2043 
2044 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2045     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2046     bd_addr_t bd_address;
2047     (void)memcpy(&bd_address, conn->address, 6);
2048 
2049 #ifdef ENABLE_CLASSIC
2050     // cache needed data
2051     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2052 #endif
2053 
2054     // connection failed, remove entry
2055     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2056     btstack_memory_hci_connection_free( conn );
2057 
2058 #ifdef ENABLE_CLASSIC
2059     // notify client if dedicated bonding
2060     if (notify_dedicated_bonding_failed){
2061         log_info("hci notify_dedicated_bonding_failed");
2062         hci_emit_dedicated_bonding_result(bd_address, status);
2063     }
2064 
2065     // if authentication error, also delete link key
2066     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2067         gap_drop_link_key_for_bd_addr(bd_address);
2068     }
2069 #else
2070     UNUSED(status);
2071 #endif
2072 }
2073 
2074 #ifdef ENABLE_CLASSIC
2075 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2076     // SSP Controller
2077     if (features[6] & (1 << 3)){
2078         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2079     }
2080     // eSCO
2081     if (features[3] & (1<<7)){
2082         conn->remote_supported_features[0] |= 1;
2083     }
2084     // Extended features
2085     if (features[7] & (1<<7)){
2086         conn->remote_supported_features[0] |= 2;
2087     }
2088 }
2089 
2090 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2091     // SSP Host
2092     if (features[0] & (1 << 0)){
2093         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2094     }
2095     // SC Host
2096     if (features[0] & (1 << 3)){
2097         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2098     }
2099 }
2100 
2101 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2102     // SC Controller
2103     if (features[1] & (1 << 0)){
2104         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2105     }
2106 }
2107 
2108 static void hci_handle_remote_features_received(hci_connection_t * conn){
2109     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2110     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2111     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2112     if (conn->bonding_flags & BONDING_DEDICATED){
2113         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2114     }
2115 }
2116 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2117     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2118     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2119 }
2120 
2121 #endif
2122 
2123 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2124     // handle BT initialization
2125     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2126         hci_initializing_event_handler(packet, size);
2127     }
2128 
2129     // help with BT sleep
2130     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2131         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2132         && (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable))) {
2133         hci_initializing_next_state();
2134     }
2135 }
2136 
2137 #ifdef ENABLE_CLASSIC
2138 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2139     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2140     conn->encryption_key_size = encryption_key_size;
2141 
2142     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2143         conn->requested_security_level = LEVEL_0;
2144         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2145         return;
2146     }
2147 
2148     // Request remote features if not already done
2149     hci_trigger_remote_features_for_connection(conn);
2150 
2151     // Request Authentication if not already done
2152     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2153     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2154 }
2155 #endif
2156 
2157 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2158     UNUSED(size);
2159 
2160     uint16_t manufacturer;
2161 #ifdef ENABLE_CLASSIC
2162     hci_con_handle_t handle;
2163     hci_connection_t * conn;
2164     uint8_t status;
2165 #endif
2166     // get num cmd packets - limit to 1 to reduce complexity
2167     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2168 
2169     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2170     switch (opcode){
2171         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2172             if (packet[5]) break;
2173             // terminate, name 248 chars
2174             packet[6+248] = 0;
2175             log_info("local name: %s", &packet[6]);
2176             break;
2177         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2178             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2179             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2180                 uint16_t acl_len = little_endian_read_16(packet, 6);
2181                 uint16_t sco_len = packet[8];
2182 
2183                 // determine usable ACL/SCO payload size
2184                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2185                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2186 
2187                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2188                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2189 
2190                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2191                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2192                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2193             }
2194             break;
2195         case HCI_OPCODE_HCI_READ_RSSI:
2196             if (packet[5] == ERROR_CODE_SUCCESS){
2197                 uint8_t event[5];
2198                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2199                 event[1] = 3;
2200                 (void)memcpy(&event[2], &packet[6], 3);
2201                 hci_emit_event(event, sizeof(event), 1);
2202             }
2203             break;
2204 #ifdef ENABLE_BLE
2205         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2206             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2207             hci_stack->le_acl_packets_total_num = packet[8];
2208             // determine usable ACL payload size
2209             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2210                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2211             }
2212             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2213             break;
2214 #endif
2215 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2216         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2217             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2218             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2219             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);
2220             break;
2221 #endif
2222 #ifdef ENABLE_LE_CENTRAL
2223         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2224             hci_stack->le_whitelist_capacity = packet[6];
2225             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2226             break;
2227 #endif
2228         case HCI_OPCODE_HCI_READ_BD_ADDR:
2229             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2230             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));
2231 #ifdef ENABLE_CLASSIC
2232             if (hci_stack->link_key_db){
2233                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2234             }
2235 #endif
2236             break;
2237 #ifdef ENABLE_CLASSIC
2238         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2239             hci_emit_discoverable_enabled(hci_stack->discoverable);
2240             break;
2241         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2242             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2243                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2244                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2245                 hci_emit_event(event, sizeof(event), 1);
2246             }
2247             break;
2248 #endif
2249         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2250             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2251 
2252 #ifdef ENABLE_CLASSIC
2253             // determine usable ACL packet types based on host buffer size and supported features
2254             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2255             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2256 #endif
2257             // Classic/LE
2258             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2259             break;
2260         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2261             manufacturer = little_endian_read_16(packet, 10);
2262             // map Cypress to Broadcom
2263             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2264                 log_info("Treat Cypress as Broadcom");
2265                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2266                 little_endian_store_16(packet, 10, manufacturer);
2267             }
2268             hci_stack->manufacturer = manufacturer;
2269             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2270             break;
2271         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2272             hci_stack->local_supported_commands[0] =
2273                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2274                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2275                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2276                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2277                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2278                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2279                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2280                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2281             hci_stack->local_supported_commands[1] =
2282                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2283                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2284                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2285                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2286                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2287             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2288             break;
2289 #ifdef ENABLE_CLASSIC
2290         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2291             if (packet[5]) return;
2292             hci_stack->synchronous_flow_control_enabled = 1;
2293             break;
2294         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2295             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2296             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2297             conn   = hci_connection_for_handle(handle);
2298             if (conn != NULL) {
2299                 uint8_t key_size = 0;
2300                 if (status == 0){
2301                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2302                     log_info("Handle %04x key Size: %u", handle, key_size);
2303                 } else {
2304                     key_size = 1;
2305                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2306                 }
2307                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2308             }
2309             break;
2310         // assert pairing complete event is emitted.
2311         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2312         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2313         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2314         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2315             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2316             // lookup connection by gap pairing addr
2317             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2318             if (conn == NULL) break;
2319             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2320             break;
2321 
2322 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2323         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2324         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2325             uint8_t event[67];
2326             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2327             event[1] = 65;
2328             (void)memset(&event[2], 0, 65);
2329             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2330                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2331                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2332                     event[2] = 3;
2333                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2334                 } else {
2335                     event[2] = 1;
2336                 }
2337             }
2338             hci_emit_event(event, sizeof(event), 0);
2339             break;
2340         }
2341 
2342         // note: only needed if user does not provide OOB data
2343         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2344             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2345             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2346             if (conn == NULL) break;
2347             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2348             break;
2349 #endif
2350 #endif
2351         default:
2352             break;
2353     }
2354 }
2355 
2356 #ifdef ENABLE_BLE
2357 static void event_handle_le_connection_complete(const uint8_t * packet){
2358 	bd_addr_t addr;
2359 	bd_addr_type_t addr_type;
2360 	hci_connection_t * conn;
2361 
2362 	// Connection management
2363 	reverse_bd_addr(&packet[8], addr);
2364 	addr_type = (bd_addr_type_t)packet[7];
2365 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2366 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2367 
2368 #ifdef ENABLE_LE_CENTRAL
2369 	// handle error: error is reported only to the initiator -> outgoing connection
2370 	if (packet[3]){
2371 
2372 		// handle cancelled outgoing connection
2373 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2374 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2375 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2376 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2377 		    // reset state
2378             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2379             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2380 			// get outgoing connection conn struct for direct connect
2381 			conn = gap_get_outgoing_connection();
2382 		}
2383 
2384 		// outgoing le connection establishment is done
2385 		if (conn){
2386 			// remove entry
2387 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2388 			btstack_memory_hci_connection_free( conn );
2389 		}
2390 		return;
2391 	}
2392 #endif
2393 
2394 	// on success, both hosts receive connection complete event
2395 	if (packet[6] == HCI_ROLE_MASTER){
2396 #ifdef ENABLE_LE_CENTRAL
2397 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2398 		// note: no hci_connection_t object exists yet for connect with whitelist
2399 		if (hci_is_le_connection_type(addr_type)){
2400 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2401 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2402 		}
2403 #endif
2404 	} else {
2405 #ifdef ENABLE_LE_PERIPHERAL
2406 		// if we're slave, it was an incoming connection, advertisements have stopped
2407 		hci_stack->le_advertisements_active = false;
2408 #endif
2409 	}
2410 
2411 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2412 	if (!conn){
2413 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2414 	}
2415 
2416 	// no memory, sorry.
2417 	if (!conn){
2418 		return;
2419 	}
2420 
2421 	conn->state = OPEN;
2422 	conn->role  = packet[6];
2423 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2424 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2425 
2426 #ifdef ENABLE_LE_PERIPHERAL
2427 	if (packet[6] == HCI_ROLE_SLAVE){
2428 		hci_update_advertisements_enabled_for_current_roles();
2429 	}
2430 #endif
2431 
2432     // init unenhanced att bearer mtu
2433     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2434     conn->att_connection.mtu_exchanged = false;
2435 
2436     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2437 
2438 	// restart timer
2439 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2440 	// btstack_run_loop_add_timer(&conn->timeout);
2441 
2442 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2443 
2444 	hci_emit_nr_connections_changed();
2445 }
2446 #endif
2447 
2448 #ifdef ENABLE_CLASSIC
2449 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){
2450     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2451     // LEVEL_4 is tested by l2cap
2452     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2453     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2454     if (level >= LEVEL_3){
2455         // MITM not possible without keyboard or display
2456         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2457         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2458 
2459         // MITM possible if one side has keyboard and the other has keyboard or display
2460         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2461         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2462 
2463         // MITM not possible if one side has only display and other side has no keyboard
2464         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2465         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2466     }
2467     // LEVEL 2 requires SSP, which is a given
2468     return true;
2469 }
2470 
2471 static bool btstack_is_null(uint8_t * data, uint16_t size){
2472     uint16_t i;
2473     for (i=0; i < size ; i++){
2474         if (data[i] != 0) {
2475             return false;
2476         }
2477     }
2478     return true;
2479 }
2480 
2481 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2482     // get requested security level
2483     gap_security_level_t requested_security_level = conn->requested_security_level;
2484     if (hci_stack->gap_secure_connections_only_mode){
2485         requested_security_level = LEVEL_4;
2486     }
2487 
2488     // assess security: LEVEL 4 requires SC
2489     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2490     if ((requested_security_level == LEVEL_4) &&
2491         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2492         !hci_remote_sc_enabled(conn)){
2493         log_info("Level 4 required, but SC not supported -> abort");
2494         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2495         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2496         return;
2497     }
2498 
2499     // assess security based on io capabilities
2500     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2501         // responder: fully validate io caps of both sides as well as OOB data
2502         bool security_possible = false;
2503         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2504 
2505 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2506         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2507         // so we merge the OOB data availability
2508         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2509         if (conn->classic_oob_c_192 != NULL){
2510             have_oob_data |= 1;
2511         }
2512         if (conn->classic_oob_c_256 != NULL){
2513             have_oob_data |= 2;
2514         }
2515         // for up to Level 3, either P-192 as well as P-256 will do
2516         // 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
2517         // if remote does not SC, we should not receive P-256 data either
2518         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2519             security_possible = true;
2520         }
2521         // for Level 4, P-256 is needed
2522         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2523             security_possible = true;
2524         }
2525 #endif
2526 
2527         if (security_possible == false){
2528             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2529             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2530             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2531             return;
2532         }
2533     } else {
2534         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2535 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2536 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2537         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2538             log_info("Level 3+ required, but no input/output -> abort");
2539             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2540             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2541             return;
2542         }
2543 #endif
2544 #endif
2545     }
2546 
2547 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2548     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2549         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2550     } else {
2551         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2552     }
2553 #endif
2554 }
2555 
2556 #endif
2557 
2558 static void event_handler(uint8_t *packet, uint16_t size){
2559 
2560     uint16_t event_length = packet[1];
2561 
2562     // assert packet is complete
2563     if (size != (event_length + 2u)){
2564         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2565         return;
2566     }
2567 
2568     bd_addr_type_t addr_type;
2569     hci_con_handle_t handle;
2570     hci_connection_t * conn;
2571     int i;
2572     int create_connection_cmd;
2573 
2574 #ifdef ENABLE_CLASSIC
2575     hci_link_type_t link_type;
2576     bd_addr_t addr;
2577 #endif
2578 
2579     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2580 
2581     switch (hci_event_packet_get_type(packet)) {
2582 
2583         case HCI_EVENT_COMMAND_COMPLETE:
2584             handle_command_complete_event(packet, size);
2585             break;
2586 
2587         case HCI_EVENT_COMMAND_STATUS:
2588             // get num cmd packets - limit to 1 to reduce complexity
2589             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2590 
2591             // check command status to detected failed outgoing connections
2592             create_connection_cmd = 0;
2593 #ifdef ENABLE_CLASSIC
2594             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2595                 create_connection_cmd = 1;
2596             }
2597 #endif
2598 #ifdef ENABLE_LE_CENTRAL
2599             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2600                 create_connection_cmd = 1;
2601             }
2602 #endif
2603             if (create_connection_cmd) {
2604                 uint8_t status = hci_event_command_status_get_status(packet);
2605                 addr_type = hci_stack->outgoing_addr_type;
2606                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2607                 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);
2608 
2609                 // reset outgoing address info
2610                 memset(hci_stack->outgoing_addr, 0, 6);
2611                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2612 
2613                 // on error
2614                 if (status != ERROR_CODE_SUCCESS){
2615 #ifdef ENABLE_LE_CENTRAL
2616                     if (hci_is_le_connection_type(addr_type)){
2617                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2618                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2619                     }
2620 #endif
2621                     // error => outgoing connection failed
2622                     if (conn != NULL){
2623                         hci_handle_connection_failed(conn, status);
2624                     }
2625                 }
2626             }
2627 
2628 #ifdef ENABLE_CLASSIC
2629             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2630                 uint8_t status = hci_event_command_status_get_status(packet);
2631                 log_info("command status (inquiry), status %x", status);
2632                 if (status == ERROR_CODE_SUCCESS) {
2633                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2634                 } else {
2635                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2636                 }
2637             }
2638 #endif
2639             break;
2640 
2641         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2642             if (size < 3) return;
2643             uint16_t num_handles = packet[2];
2644             if (size != (3u + num_handles * 4u)) return;
2645             uint16_t offset = 3;
2646             for (i=0; i<num_handles;i++){
2647                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2648                 offset += 2u;
2649                 uint16_t num_packets = little_endian_read_16(packet, offset);
2650                 offset += 2u;
2651 
2652                 conn = hci_connection_for_handle(handle);
2653                 if (!conn){
2654                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2655                     continue;
2656                 }
2657 
2658                 if (conn->num_packets_sent >= num_packets){
2659                     conn->num_packets_sent -= num_packets;
2660                 } else {
2661                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2662                     conn->num_packets_sent = 0;
2663                 }
2664                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2665 
2666 #ifdef ENABLE_CLASSIC
2667                 // For SCO, we do the can_send_now_check here
2668                 hci_notify_if_sco_can_send_now();
2669 #endif
2670             }
2671             break;
2672         }
2673 
2674 #ifdef ENABLE_CLASSIC
2675         case HCI_EVENT_INQUIRY_COMPLETE:
2676             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2677                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2678                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2679                 hci_emit_event(event, sizeof(event), 1);
2680             }
2681             break;
2682         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2683             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2684                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2685             }
2686             break;
2687         case HCI_EVENT_CONNECTION_REQUEST:
2688             reverse_bd_addr(&packet[2], addr);
2689             link_type = (hci_link_type_t) packet[11];
2690 
2691             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2692             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2693                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2694                 bd_addr_copy(hci_stack->decline_addr, addr);
2695                 break;
2696             }
2697 
2698             if (hci_stack->gap_classic_accept_callback != NULL){
2699                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2700                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2701                     bd_addr_copy(hci_stack->decline_addr, addr);
2702                     break;
2703                 }
2704             }
2705 
2706             // TODO: eval COD 8-10
2707             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2708             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2709             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2710             if (!conn) {
2711                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2712             }
2713             if (!conn) {
2714                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2715                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2716                 bd_addr_copy(hci_stack->decline_addr, addr);
2717                 hci_run();
2718                 // avoid event to higher layer
2719                 return;
2720             }
2721             conn->role  = HCI_ROLE_SLAVE;
2722             conn->state = RECEIVED_CONNECTION_REQUEST;
2723             // store info about eSCO
2724             if (link_type == HCI_LINK_TYPE_ESCO){
2725                 conn->remote_supported_features[0] |= 1;
2726             }
2727             hci_run();
2728             break;
2729 
2730         case HCI_EVENT_CONNECTION_COMPLETE:
2731             // Connection management
2732             reverse_bd_addr(&packet[5], addr);
2733             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2734             addr_type = BD_ADDR_TYPE_ACL;
2735             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2736             if (conn) {
2737                 if (!packet[2]){
2738                     conn->state = OPEN;
2739                     conn->con_handle = little_endian_read_16(packet, 3);
2740 
2741                     // queue set supervision timeout if we're master
2742                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2743                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2744                     }
2745 
2746                     // restart timer
2747                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2748                     btstack_run_loop_add_timer(&conn->timeout);
2749 
2750                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2751 
2752                     hci_emit_nr_connections_changed();
2753                 } else {
2754                     // connection failed
2755                     hci_handle_connection_failed(conn, packet[2]);
2756                 }
2757             }
2758             break;
2759 
2760         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2761             reverse_bd_addr(&packet[5], addr);
2762             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2763             if (packet[2]){
2764                 // connection failed
2765                 break;
2766             }
2767             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2768             if (!conn) {
2769                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2770             }
2771             if (!conn) {
2772                 break;
2773             }
2774             conn->state = OPEN;
2775             conn->con_handle = little_endian_read_16(packet, 3);
2776 
2777 #ifdef ENABLE_SCO_OVER_HCI
2778             // update SCO
2779             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2780                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2781             }
2782             // trigger can send now
2783             if (hci_have_usb_transport()){
2784                 hci_stack->sco_can_send_now = true;
2785             }
2786 #endif
2787 #ifdef HAVE_SCO_TRANSPORT
2788             // configure sco transport
2789             if (hci_stack->sco_transport != NULL){
2790                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2791                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2792             }
2793 #endif
2794             break;
2795 
2796         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2797             handle = little_endian_read_16(packet, 3);
2798             conn = hci_connection_for_handle(handle);
2799             if (!conn) break;
2800             if (!packet[2]){
2801                 const uint8_t * features = &packet[5];
2802                 hci_handle_remote_features_page_0(conn, features);
2803 
2804                 // read extended features if possible
2805                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2806                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2807                     break;
2808                 }
2809             }
2810             hci_handle_remote_features_received(conn);
2811             break;
2812 
2813         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2814             handle = little_endian_read_16(packet, 3);
2815             conn = hci_connection_for_handle(handle);
2816             if (!conn) break;
2817             // status = ok, page = 1
2818             if (!packet[2]) {
2819                 uint8_t page_number = packet[5];
2820                 uint8_t maximum_page_number = packet[6];
2821                 const uint8_t * features = &packet[7];
2822                 bool done = false;
2823                 switch (page_number){
2824                     case 1:
2825                         hci_handle_remote_features_page_1(conn, features);
2826                         if (maximum_page_number >= 2){
2827                             // get Secure Connections (Controller) from Page 2 if available
2828                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2829                         } else {
2830                             // otherwise, assume SC (Controller) == SC (Host)
2831                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2832                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2833                             }
2834                             done = true;
2835                         }
2836                         break;
2837                     case 2:
2838                         hci_handle_remote_features_page_2(conn, features);
2839                         done = true;
2840                         break;
2841                     default:
2842                         break;
2843                 }
2844                 if (!done) break;
2845             }
2846             hci_handle_remote_features_received(conn);
2847             break;
2848 
2849         case HCI_EVENT_LINK_KEY_REQUEST:
2850 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2851             hci_event_link_key_request_get_bd_addr(packet, addr);
2852             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2853             if (!conn) break;
2854 
2855             // lookup link key in db if not cached
2856             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2857                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2858             }
2859 
2860             // response sent by hci_run()
2861             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2862 #endif
2863             break;
2864 
2865         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2866             hci_event_link_key_request_get_bd_addr(packet, addr);
2867             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2868             if (!conn) break;
2869 
2870             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2871 
2872             // CVE-2020-26555: ignore NULL link key
2873             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2874             if (btstack_is_null(&packet[8], 16)) break;
2875 
2876             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2877             // Change Connection Encryption keeps link key type
2878             if (link_key_type != CHANGED_COMBINATION_KEY){
2879                 conn->link_key_type = link_key_type;
2880             }
2881 
2882             // cache link key. link keys stored in little-endian format for legacy reasons
2883             memcpy(&conn->link_key, &packet[8], 16);
2884 
2885             // only store link key:
2886             // - if bondable enabled
2887             if (hci_stack->bondable == false) break;
2888             // - if security level sufficient
2889             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2890             // - for SSP, also check if remote side requested bonding as well
2891             if (conn->link_key_type != COMBINATION_KEY){
2892                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2893                 if (!remote_bonding){
2894                     break;
2895                 }
2896             }
2897             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2898             break;
2899         }
2900 
2901         case HCI_EVENT_PIN_CODE_REQUEST:
2902             hci_event_pin_code_request_get_bd_addr(packet, addr);
2903             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2904             if (!conn) break;
2905 
2906             hci_pairing_started(conn, false);
2907             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2908             if (!hci_stack->bondable ){
2909                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2910                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2911                 hci_run();
2912                 return;
2913             }
2914             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2915             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2916                 log_info("Level 4 required, but SC not supported -> abort");
2917                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2918                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2919                 hci_run();
2920                 return;
2921             }
2922             break;
2923 
2924         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2925             hci_event_io_capability_response_get_bd_addr(packet, addr);
2926             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2927             if (!conn) break;
2928 
2929             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2930             hci_pairing_started(conn, true);
2931             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2932             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2933 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2934             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2935 #endif
2936             break;
2937 
2938         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2939             hci_event_io_capability_response_get_bd_addr(packet, addr);
2940             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2941             if (!conn) break;
2942 
2943             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2944             hci_connection_timestamp(conn);
2945             hci_pairing_started(conn, true);
2946             break;
2947 
2948 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2949         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2950             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2951             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2952             if (!conn) break;
2953 
2954             hci_connection_timestamp(conn);
2955 
2956             hci_pairing_started(conn, true);
2957 
2958             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2959             break;
2960 #endif
2961 
2962         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2963             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2964             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2965             if (!conn) break;
2966             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2967                 if (hci_stack->ssp_auto_accept){
2968                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2969                 };
2970             } else {
2971                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2972                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2973                 // don't forward event to app
2974                 hci_run();
2975                 return;
2976             }
2977             break;
2978 
2979         case HCI_EVENT_USER_PASSKEY_REQUEST:
2980             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2981             if (hci_stack->ssp_auto_accept){
2982                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2983             };
2984             break;
2985 
2986         case HCI_EVENT_MODE_CHANGE:
2987             handle = hci_event_mode_change_get_handle(packet);
2988             conn = hci_connection_for_handle(handle);
2989             if (!conn) break;
2990             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2991             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2992             break;
2993 #endif
2994 
2995         case HCI_EVENT_ENCRYPTION_CHANGE:
2996             handle = hci_event_encryption_change_get_connection_handle(packet);
2997             conn = hci_connection_for_handle(handle);
2998             if (!conn) break;
2999             if (hci_event_encryption_change_get_status(packet) == 0u) {
3000                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3001                 if (encryption_enabled){
3002                     if (hci_is_le_connection(conn)){
3003                         // For LE, we accept connection as encrypted
3004                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3005                     }
3006 #ifdef ENABLE_CLASSIC
3007                     else {
3008 
3009                         // dedicated bonding: send result and disconnect
3010                         if (conn->bonding_flags & BONDING_DEDICATED){
3011                             conn->bonding_flags &= ~BONDING_DEDICATED;
3012                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3013                             conn->bonding_status = packet[2];
3014                             break;
3015                         }
3016 
3017                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3018                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3019                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3020                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3021                             log_info("SC during pairing, but only E0 now -> abort");
3022                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3023                             break;
3024                         }
3025 
3026                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3027                         if (connected_uses_aes_ccm){
3028                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3029                         }
3030 
3031 #ifdef ENABLE_TESTING_SUPPORT
3032                         // work around for issue with PTS dongle
3033                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3034 #endif
3035 
3036                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3037                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3038                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3039                         } else {
3040                             // if not, pretend everything is perfect
3041                             hci_handle_read_encryption_key_size_complete(conn, 16);
3042                         }
3043                     }
3044 #endif
3045                 } else {
3046                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3047                 }
3048             }
3049 
3050             break;
3051 
3052 #ifdef ENABLE_CLASSIC
3053         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3054             handle = hci_event_authentication_complete_get_connection_handle(packet);
3055             conn = hci_connection_for_handle(handle);
3056             if (!conn) break;
3057 
3058             // clear authentication active flag
3059             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3060             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3061 
3062             // authenticated only if auth status == 0
3063             if (hci_event_authentication_complete_get_status(packet) == 0){
3064                 // authenticated
3065                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3066 
3067                 // If not already encrypted, start encryption
3068                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3069                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3070                     break;
3071                 }
3072             }
3073 
3074             // emit updated security level
3075             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3076             break;
3077 
3078         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3079             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3080             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3081             if (!conn) break;
3082 
3083             // treat successfully paired connection as authenticated
3084             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3085                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3086             }
3087 
3088             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3089             break;
3090 #endif
3091 
3092         // HCI_EVENT_DISCONNECTION_COMPLETE
3093         // has been split, to first notify stack before shutting connection down
3094         // see end of function, too.
3095         case HCI_EVENT_DISCONNECTION_COMPLETE:
3096             if (packet[2]) break;   // status != 0
3097             handle = little_endian_read_16(packet, 3);
3098             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3099             if (hci_stack->acl_fragmentation_total_size > 0u) {
3100                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3101                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3102                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3103                     hci_stack->acl_fragmentation_total_size = 0;
3104                     hci_stack->acl_fragmentation_pos = 0;
3105                     if (release_buffer){
3106                         hci_release_packet_buffer();
3107                     }
3108                 }
3109             }
3110 
3111             conn = hci_connection_for_handle(handle);
3112             if (!conn) break;
3113 #ifdef ENABLE_CLASSIC
3114             // pairing failed if it was ongoing
3115             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3116 #endif
3117 
3118             // emit dedicatd bonding event
3119             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3120                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3121             }
3122 
3123             // mark connection for shutdown, stop timers, reset state
3124             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3125             hci_connection_stop_timer(conn);
3126             hci_connection_init(conn);
3127 
3128 #ifdef ENABLE_BLE
3129 #ifdef ENABLE_LE_PERIPHERAL
3130             // re-enable advertisements for le connections if active
3131             if (hci_is_le_connection(conn)){
3132                 hci_update_advertisements_enabled_for_current_roles();
3133             }
3134 #endif
3135 #endif
3136             break;
3137 
3138         case HCI_EVENT_HARDWARE_ERROR:
3139             log_error("Hardware Error: 0x%02x", packet[2]);
3140             if (hci_stack->hardware_error_callback){
3141                 (*hci_stack->hardware_error_callback)(packet[2]);
3142             } else {
3143                 // if no special requests, just reboot stack
3144                 hci_power_control_off();
3145                 hci_power_control_on();
3146             }
3147             break;
3148 
3149 #ifdef ENABLE_CLASSIC
3150         case HCI_EVENT_ROLE_CHANGE:
3151             if (packet[2]) break;   // status != 0
3152             reverse_bd_addr(&packet[3], addr);
3153             addr_type = BD_ADDR_TYPE_ACL;
3154             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3155             if (!conn) break;
3156             conn->role = packet[9];
3157             break;
3158 #endif
3159 
3160         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3161             // release packet buffer only for asynchronous transport and if there are not further fragements
3162             if (hci_transport_synchronous()) {
3163                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3164                 return; // instead of break: to avoid re-entering hci_run()
3165             }
3166             hci_stack->acl_fragmentation_tx_active = 0;
3167             if (hci_stack->acl_fragmentation_total_size) break;
3168             hci_release_packet_buffer();
3169 
3170             // L2CAP receives this event via the hci_emit_event below
3171 
3172 #ifdef ENABLE_CLASSIC
3173             // For SCO, we do the can_send_now_check here
3174             hci_notify_if_sco_can_send_now();
3175 #endif
3176             break;
3177 
3178 #ifdef ENABLE_CLASSIC
3179         case HCI_EVENT_SCO_CAN_SEND_NOW:
3180             // For SCO, we do the can_send_now_check here
3181             hci_stack->sco_can_send_now = true;
3182             hci_notify_if_sco_can_send_now();
3183             return;
3184 
3185         // explode inquriy results for easier consumption
3186         case HCI_EVENT_INQUIRY_RESULT:
3187         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3188         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3189             gap_inquiry_explode(packet, size);
3190             break;
3191 #endif
3192 
3193 #ifdef ENABLE_BLE
3194         case HCI_EVENT_LE_META:
3195             switch (packet[2]){
3196 #ifdef ENABLE_LE_CENTRAL
3197                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3198                     // log_info("advertising report received");
3199                     if (!hci_stack->le_scanning_enabled) break;
3200                     le_handle_advertisement_report(packet, size);
3201                     break;
3202 #endif
3203                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3204 					event_handle_le_connection_complete(packet);
3205                     break;
3206 
3207                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3208                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3209                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3210                     conn = hci_connection_for_handle(handle);
3211                     if (!conn) break;
3212                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3213                     break;
3214 
3215                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3216                     // connection
3217                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3218                     conn = hci_connection_for_handle(handle);
3219                     if (conn) {
3220                         // read arguments
3221                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3222                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3223                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3224                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3225 
3226                         // validate against current connection parameter range
3227                         le_connection_parameter_range_t existing_range;
3228                         gap_get_connection_parameter_range(&existing_range);
3229                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3230                         if (update_parameter){
3231                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3232                             conn->le_conn_interval_min = le_conn_interval_min;
3233                             conn->le_conn_interval_max = le_conn_interval_max;
3234                             conn->le_conn_latency = le_conn_latency;
3235                             conn->le_supervision_timeout = le_supervision_timeout;
3236                         } else {
3237                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3238                         }
3239                     }
3240                     break;
3241 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3242                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3243                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3244                     conn = hci_connection_for_handle(handle);
3245                     if (conn) {
3246                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3247                     }
3248                     break;
3249 #endif
3250                 default:
3251                     break;
3252             }
3253             break;
3254 #endif
3255         case HCI_EVENT_VENDOR_SPECIFIC:
3256             // Vendor specific commands often create vendor specific event instead of num completed packets
3257             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3258             switch (hci_stack->manufacturer){
3259                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3260                     hci_stack->num_cmd_packets = 1;
3261                     break;
3262                 default:
3263                     break;
3264             }
3265             break;
3266         default:
3267             break;
3268     }
3269 
3270     handle_event_for_current_stack_state(packet, size);
3271 
3272     // notify upper stack
3273 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3274 
3275     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3276     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3277 		handle = little_endian_read_16(packet, 3);
3278 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3279 		// discard connection if app did not trigger a reconnect in the event handler
3280 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3281 			hci_shutdown_connection(aConn);
3282 		}
3283     }
3284 
3285 	// execute main loop
3286 	hci_run();
3287 }
3288 
3289 #ifdef ENABLE_CLASSIC
3290 
3291 #ifdef ENABLE_SCO_OVER_HCI
3292 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3293 static void sco_schedule_tx(hci_connection_t * conn);
3294 
3295 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3296     log_debug("SCO TX Timeout");
3297     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3298     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3299     if (!conn) return;
3300 
3301     // trigger send
3302     conn->sco_tx_ready = 1;
3303     // extra packet if CVSD but SCO buffer is too short
3304     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3305         conn->sco_tx_ready++;
3306     }
3307     hci_notify_if_sco_can_send_now();
3308 }
3309 
3310 
3311 #define SCO_TX_AFTER_RX_MS (6)
3312 
3313 static void sco_schedule_tx(hci_connection_t * conn){
3314 
3315     uint32_t now = btstack_run_loop_get_time_ms();
3316     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3317     int time_delta_ms = sco_tx_ms - now;
3318 
3319     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3320 
3321     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3322     btstack_run_loop_remove_timer(timer);
3323     btstack_run_loop_set_timer(timer, time_delta_ms);
3324     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3325     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3326     btstack_run_loop_add_timer(timer);
3327 }
3328 #endif
3329 
3330 static void sco_handler(uint8_t * packet, uint16_t size){
3331     // lookup connection struct
3332     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3333     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3334     if (!conn) return;
3335 
3336 #ifdef ENABLE_SCO_OVER_HCI
3337     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3338     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3339         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3340             packet[2] = 0x3c;
3341             memmove(&packet[3], &packet[23], 63);
3342             size = 63;
3343         }
3344     }
3345 
3346     if (hci_have_usb_transport()){
3347         // Nothing to do
3348     } else {
3349         // 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);
3350         if (hci_stack->synchronous_flow_control_enabled == 0){
3351             uint32_t now = btstack_run_loop_get_time_ms();
3352 
3353             if (!conn->sco_rx_valid){
3354                 // ignore first 10 packets
3355                 conn->sco_rx_count++;
3356                 // log_debug("sco rx count %u", conn->sco_rx_count);
3357                 if (conn->sco_rx_count == 10) {
3358                     // use first timestamp as is and pretent it just started
3359                     conn->sco_rx_ms = now;
3360                     conn->sco_rx_valid = 1;
3361                     conn->sco_rx_count = 0;
3362                     sco_schedule_tx(conn);
3363                 }
3364             } else {
3365                 // track expected arrival timme
3366                 conn->sco_rx_count++;
3367                 conn->sco_rx_ms += 7;
3368                 int delta = (int32_t) (now - conn->sco_rx_ms);
3369                 if (delta > 0){
3370                     conn->sco_rx_ms++;
3371                 }
3372                 // log_debug("sco rx %u", conn->sco_rx_ms);
3373                 sco_schedule_tx(conn);
3374             }
3375         }
3376     }
3377 #endif
3378 
3379     // deliver to app
3380     if (hci_stack->sco_packet_handler) {
3381         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3382     }
3383 
3384 #ifdef HAVE_SCO_TRANSPORT
3385     // We can send one packet for each received packet
3386     conn->sco_tx_ready++;
3387     hci_notify_if_sco_can_send_now();
3388 #endif
3389 
3390 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3391     conn->num_packets_completed++;
3392     hci_stack->host_completed_packets = 1;
3393     hci_run();
3394 #endif
3395 }
3396 #endif
3397 
3398 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3399     hci_dump_packet(packet_type, 1, packet, size);
3400     switch (packet_type) {
3401         case HCI_EVENT_PACKET:
3402             event_handler(packet, size);
3403             break;
3404         case HCI_ACL_DATA_PACKET:
3405             acl_handler(packet, size);
3406             break;
3407 #ifdef ENABLE_CLASSIC
3408         case HCI_SCO_DATA_PACKET:
3409             sco_handler(packet, size);
3410             break;
3411 #endif
3412         default:
3413             break;
3414     }
3415 }
3416 
3417 /**
3418  * @brief Add event packet handler.
3419  */
3420 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3421     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3422 }
3423 
3424 /**
3425  * @brief Remove event packet handler.
3426  */
3427 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3428     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3429 }
3430 
3431 /** Register HCI packet handlers */
3432 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3433     hci_stack->acl_packet_handler = handler;
3434 }
3435 
3436 #ifdef ENABLE_CLASSIC
3437 /**
3438  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3439  */
3440 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3441     hci_stack->sco_packet_handler = handler;
3442 }
3443 #endif
3444 
3445 static void hci_state_reset(void){
3446     // no connections yet
3447     hci_stack->connections = NULL;
3448 
3449     // keep discoverable/connectable as this has been requested by the client(s)
3450     // hci_stack->discoverable = 0;
3451     // hci_stack->connectable = 0;
3452     // hci_stack->bondable = 1;
3453     // hci_stack->own_addr_type = 0;
3454 
3455     // buffer is free
3456     hci_stack->hci_packet_buffer_reserved = false;
3457 
3458     // no pending cmds
3459     hci_stack->decline_reason = 0;
3460 
3461     hci_stack->secure_connections_active = false;
3462 
3463 #ifdef ENABLE_CLASSIC
3464     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3465     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3466 
3467     hci_stack->gap_tasks =
3468             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3469             GAP_TASK_SET_CLASS_OF_DEVICE |
3470             GAP_TASK_SET_LOCAL_NAME |
3471             GAP_TASK_SET_EIR_DATA |
3472             GAP_TASK_WRITE_SCAN_ENABLE |
3473             GAP_TASK_WRITE_PAGE_TIMEOUT;
3474 #endif
3475 
3476 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3477     hci_stack->classic_read_local_oob_data = false;
3478     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3479 #endif
3480 
3481     // LE
3482 #ifdef ENABLE_BLE
3483     memset(hci_stack->le_random_address, 0, 6);
3484     hci_stack->le_random_address_set = 0;
3485 #endif
3486 #ifdef ENABLE_LE_CENTRAL
3487     hci_stack->le_scanning_active  = false;
3488     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3489     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3490     hci_stack->le_whitelist_capacity = 0;
3491 #endif
3492 #ifdef ENABLE_LE_PERIPHERAL
3493     hci_stack->le_advertisements_active = false;
3494     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3495         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3496     }
3497     if (hci_stack->le_advertisements_data != NULL){
3498         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3499     }
3500 #endif
3501 }
3502 
3503 #ifdef ENABLE_CLASSIC
3504 /**
3505  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3506  */
3507 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3508     // store and open remote device db
3509     hci_stack->link_key_db = link_key_db;
3510     if (hci_stack->link_key_db) {
3511         hci_stack->link_key_db->open();
3512     }
3513 }
3514 #endif
3515 
3516 void hci_init(const hci_transport_t *transport, const void *config){
3517 
3518 #ifdef HAVE_MALLOC
3519     if (!hci_stack) {
3520         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3521     }
3522 #else
3523     hci_stack = &hci_stack_static;
3524 #endif
3525     memset(hci_stack, 0, sizeof(hci_stack_t));
3526 
3527     // reference to use transport layer implementation
3528     hci_stack->hci_transport = transport;
3529 
3530     // reference to used config
3531     hci_stack->config = config;
3532 
3533     // setup pointer for outgoing packet buffer
3534     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3535 
3536     // max acl payload size defined in config.h
3537     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3538 
3539     // register packet handlers with transport
3540     transport->register_packet_handler(&packet_handler);
3541 
3542     hci_stack->state = HCI_STATE_OFF;
3543 
3544     // class of device
3545     hci_stack->class_of_device = 0x007a020c; // Smartphone
3546 
3547     // bondable by default
3548     hci_stack->bondable = 1;
3549 
3550 #ifdef ENABLE_CLASSIC
3551     // classic name
3552     hci_stack->local_name = default_classic_name;
3553 
3554     // Master slave policy
3555     hci_stack->master_slave_policy = 1;
3556 
3557     // Allow Role Switch
3558     hci_stack->allow_role_switch = 1;
3559 
3560     // Default / minimum security level = 2
3561     hci_stack->gap_security_level = LEVEL_2;
3562 
3563     // Default Security Mode 4
3564     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3565 
3566     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3567     hci_stack->gap_required_encyrption_key_size = 7;
3568 
3569     // Link Supervision Timeout
3570     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3571 
3572 #endif
3573 
3574     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3575     hci_stack->ssp_enable = 1;
3576     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3577     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3578     hci_stack->ssp_auto_accept = 1;
3579 
3580     // Secure Connections: enable (requires support from Controller)
3581     hci_stack->secure_connections_enable = true;
3582 
3583     // voice setting - signed 16 bit pcm data with CVSD over the air
3584     hci_stack->sco_voice_setting = 0x60;
3585 
3586 #ifdef ENABLE_LE_CENTRAL
3587     // connection parameter to use for outgoing connections
3588     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3589     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3590     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3591     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3592     hci_stack->le_connection_latency      = 4;         // 4
3593     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3594     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3595     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3596 
3597     // default LE Scanning
3598     hci_stack->le_scan_type     =   0x1; // active
3599     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3600     hci_stack->le_scan_window   =  0x30; //  30 ms
3601 #endif
3602 
3603 #ifdef ENABLE_LE_PERIPHERAL
3604     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3605 #endif
3606 
3607     // connection parameter range used to answer connection parameter update requests in l2cap
3608     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3609     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3610     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3611     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3612     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3613     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3614 
3615     hci_state_reset();
3616 }
3617 
3618 void hci_deinit(void){
3619 #ifdef HAVE_MALLOC
3620     if (hci_stack) {
3621         free(hci_stack);
3622     }
3623 #endif
3624     hci_stack = NULL;
3625 
3626 #ifdef ENABLE_CLASSIC
3627     disable_l2cap_timeouts = 0;
3628 #endif
3629 }
3630 
3631 /**
3632  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3633  */
3634 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3635     hci_stack->chipset = chipset_driver;
3636 
3637     // reset chipset driver - init is also called on power_up
3638     if (hci_stack->chipset && hci_stack->chipset->init){
3639         hci_stack->chipset->init(hci_stack->config);
3640     }
3641 }
3642 
3643 /**
3644  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3645  */
3646 void hci_set_control(const btstack_control_t *hardware_control){
3647     // references to used control implementation
3648     hci_stack->control = hardware_control;
3649     // init with transport config
3650     hardware_control->init(hci_stack->config);
3651 }
3652 
3653 static void hci_discard_connections(void){
3654     btstack_linked_list_iterator_t lit;
3655     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3656     while (btstack_linked_list_iterator_has_next(&lit)){
3657         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3658         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3659         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3660         hci_shutdown_connection(connection);
3661     }
3662 }
3663 
3664 void hci_close(void){
3665 
3666 #ifdef ENABLE_CLASSIC
3667     // close remote device db
3668     if (hci_stack->link_key_db) {
3669         hci_stack->link_key_db->close();
3670     }
3671 #endif
3672 
3673     hci_discard_connections();
3674 
3675     hci_power_control(HCI_POWER_OFF);
3676 
3677 #ifdef HAVE_MALLOC
3678     free(hci_stack);
3679 #endif
3680     hci_stack = NULL;
3681 }
3682 
3683 #ifdef HAVE_SCO_TRANSPORT
3684 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3685     hci_stack->sco_transport = sco_transport;
3686     sco_transport->register_packet_handler(&packet_handler);
3687 }
3688 #endif
3689 
3690 #ifdef ENABLE_CLASSIC
3691 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3692     // validate ranage and set
3693     if (encryption_key_size < 7)  return;
3694     if (encryption_key_size > 16) return;
3695     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3696 }
3697 
3698 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3699     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3700         hci_stack->gap_security_mode = security_mode;
3701         return ERROR_CODE_SUCCESS;
3702     } else {
3703         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3704     }
3705 }
3706 
3707 gap_security_mode_t gap_get_security_mode(void){
3708     return hci_stack->gap_security_mode;
3709 }
3710 
3711 void gap_set_security_level(gap_security_level_t security_level){
3712     hci_stack->gap_security_level = security_level;
3713 }
3714 
3715 gap_security_level_t gap_get_security_level(void){
3716     if (hci_stack->gap_secure_connections_only_mode){
3717         return LEVEL_4;
3718     }
3719     return hci_stack->gap_security_level;
3720 }
3721 
3722 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3723     hci_stack->gap_minimal_service_security_level = security_level;
3724 }
3725 
3726 void gap_set_secure_connections_only_mode(bool enable){
3727     hci_stack->gap_secure_connections_only_mode = enable;
3728 }
3729 
3730 bool gap_get_secure_connections_only_mode(void){
3731     return hci_stack->gap_secure_connections_only_mode;
3732 }
3733 #endif
3734 
3735 #ifdef ENABLE_CLASSIC
3736 void gap_set_class_of_device(uint32_t class_of_device){
3737     hci_stack->class_of_device = class_of_device;
3738     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3739     hci_run();
3740 }
3741 
3742 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3743     hci_stack->default_link_policy_settings = default_link_policy_settings;
3744     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3745     hci_run();
3746 }
3747 
3748 void gap_set_allow_role_switch(bool allow_role_switch){
3749     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3750 }
3751 
3752 uint8_t hci_get_allow_role_switch(void){
3753     return  hci_stack->allow_role_switch;
3754 }
3755 
3756 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3757     hci_stack->link_supervision_timeout = link_supervision_timeout;
3758 }
3759 
3760 void hci_disable_l2cap_timeout_check(void){
3761     disable_l2cap_timeouts = 1;
3762 }
3763 #endif
3764 
3765 #ifndef HAVE_HOST_CONTROLLER_API
3766 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3767 void hci_set_bd_addr(bd_addr_t addr){
3768     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3769     hci_stack->custom_bd_addr_set = 1;
3770 }
3771 #endif
3772 
3773 // State-Module-Driver overview
3774 // state                    module  low-level
3775 // HCI_STATE_OFF             off      close
3776 // HCI_STATE_INITIALIZING,   on       open
3777 // HCI_STATE_WORKING,        on       open
3778 // HCI_STATE_HALTING,        on       open
3779 // HCI_STATE_SLEEPING,    off/sleep   close
3780 // HCI_STATE_FALLING_ASLEEP  on       open
3781 
3782 static int hci_power_control_on(void){
3783 
3784     // power on
3785     int err = 0;
3786     if (hci_stack->control && hci_stack->control->on){
3787         err = (*hci_stack->control->on)();
3788     }
3789     if (err){
3790         log_error( "POWER_ON failed");
3791         hci_emit_hci_open_failed();
3792         return err;
3793     }
3794 
3795     // int chipset driver
3796     if (hci_stack->chipset && hci_stack->chipset->init){
3797         hci_stack->chipset->init(hci_stack->config);
3798     }
3799 
3800     // init transport
3801     if (hci_stack->hci_transport->init){
3802         hci_stack->hci_transport->init(hci_stack->config);
3803     }
3804 
3805     // open transport
3806     err = hci_stack->hci_transport->open();
3807     if (err){
3808         log_error( "HCI_INIT failed, turning Bluetooth off again");
3809         if (hci_stack->control && hci_stack->control->off){
3810             (*hci_stack->control->off)();
3811         }
3812         hci_emit_hci_open_failed();
3813         return err;
3814     }
3815     return 0;
3816 }
3817 
3818 static void hci_power_control_off(void){
3819 
3820     log_info("hci_power_control_off");
3821 
3822     // close low-level device
3823     hci_stack->hci_transport->close();
3824 
3825     log_info("hci_power_control_off - hci_transport closed");
3826 
3827     // power off
3828     if (hci_stack->control && hci_stack->control->off){
3829         (*hci_stack->control->off)();
3830     }
3831 
3832     log_info("hci_power_control_off - control closed");
3833 
3834     hci_stack->state = HCI_STATE_OFF;
3835 }
3836 
3837 static void hci_power_control_sleep(void){
3838 
3839     log_info("hci_power_control_sleep");
3840 
3841 #if 0
3842     // don't close serial port during sleep
3843 
3844     // close low-level device
3845     hci_stack->hci_transport->close(hci_stack->config);
3846 #endif
3847 
3848     // sleep mode
3849     if (hci_stack->control && hci_stack->control->sleep){
3850         (*hci_stack->control->sleep)();
3851     }
3852 
3853     hci_stack->state = HCI_STATE_SLEEPING;
3854 }
3855 
3856 static int hci_power_control_wake(void){
3857 
3858     log_info("hci_power_control_wake");
3859 
3860     // wake on
3861     if (hci_stack->control && hci_stack->control->wake){
3862         (*hci_stack->control->wake)();
3863     }
3864 
3865 #if 0
3866     // open low-level device
3867     int err = hci_stack->hci_transport->open(hci_stack->config);
3868     if (err){
3869         log_error( "HCI_INIT failed, turning Bluetooth off again");
3870         if (hci_stack->control && hci_stack->control->off){
3871             (*hci_stack->control->off)();
3872         }
3873         hci_emit_hci_open_failed();
3874         return err;
3875     }
3876 #endif
3877 
3878     return 0;
3879 }
3880 
3881 static void hci_power_transition_to_initializing(void){
3882     // set up state machine
3883     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3884     hci_stack->hci_packet_buffer_reserved = false;
3885     hci_stack->state = HCI_STATE_INITIALIZING;
3886     hci_stack->substate = HCI_INIT_SEND_RESET;
3887 }
3888 
3889 // returns error
3890 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3891     int err;
3892     switch (power_mode){
3893         case HCI_POWER_ON:
3894             err = hci_power_control_on();
3895             if (err != 0) {
3896                 log_error("hci_power_control_on() error %d", err);
3897                 return err;
3898             }
3899             hci_power_transition_to_initializing();
3900             break;
3901         case HCI_POWER_OFF:
3902             // do nothing
3903             break;
3904         case HCI_POWER_SLEEP:
3905             // do nothing (with SLEEP == OFF)
3906             break;
3907         default:
3908             btstack_assert(false);
3909             break;
3910     }
3911     return ERROR_CODE_SUCCESS;
3912 }
3913 
3914 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3915     switch (power_mode){
3916         case HCI_POWER_ON:
3917             // do nothing
3918             break;
3919         case HCI_POWER_OFF:
3920             // no connections yet, just turn it off
3921             hci_power_control_off();
3922             break;
3923         case HCI_POWER_SLEEP:
3924             // no connections yet, just turn it off
3925             hci_power_control_sleep();
3926             break;
3927         default:
3928             btstack_assert(false);
3929             break;
3930     }
3931     return ERROR_CODE_SUCCESS;
3932 }
3933 
3934 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3935     switch (power_mode){
3936         case HCI_POWER_ON:
3937             // do nothing
3938             break;
3939         case HCI_POWER_OFF:
3940             // see hci_run
3941             hci_stack->state = HCI_STATE_HALTING;
3942             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3943             // setup watchdog timer for disconnect - only triggers if Controller does not respond anymore
3944             btstack_run_loop_set_timer(&hci_stack->timeout, 1000);
3945             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3946             btstack_run_loop_add_timer(&hci_stack->timeout);
3947             break;
3948         case HCI_POWER_SLEEP:
3949             // see hci_run
3950             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3951             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3952             break;
3953         default:
3954             btstack_assert(false);
3955             break;
3956     }
3957     return ERROR_CODE_SUCCESS;
3958 }
3959 
3960 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3961     switch (power_mode){
3962         case HCI_POWER_ON:
3963             hci_power_transition_to_initializing();
3964             break;
3965         case HCI_POWER_OFF:
3966             // do nothing
3967             break;
3968         case HCI_POWER_SLEEP:
3969             // see hci_run
3970             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3971             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3972             break;
3973         default:
3974             btstack_assert(false);
3975             break;
3976     }
3977     return ERROR_CODE_SUCCESS;
3978 }
3979 
3980 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3981     switch (power_mode){
3982         case HCI_POWER_ON:
3983             hci_power_transition_to_initializing();
3984             break;
3985         case HCI_POWER_OFF:
3986             // see hci_run
3987             hci_stack->state = HCI_STATE_HALTING;
3988             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3989             break;
3990         case HCI_POWER_SLEEP:
3991             // do nothing
3992             break;
3993         default:
3994             btstack_assert(false);
3995             break;
3996     }
3997     return ERROR_CODE_SUCCESS;
3998 }
3999 
4000 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4001     int err;
4002     switch (power_mode){
4003         case HCI_POWER_ON:
4004             err = hci_power_control_wake();
4005             if (err) return err;
4006             hci_power_transition_to_initializing();
4007             break;
4008         case HCI_POWER_OFF:
4009             hci_stack->state = HCI_STATE_HALTING;
4010             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4011             break;
4012         case HCI_POWER_SLEEP:
4013             // do nothing
4014             break;
4015         default:
4016             btstack_assert(false);
4017             break;
4018     }
4019     return ERROR_CODE_SUCCESS;
4020 }
4021 
4022 int hci_power_control(HCI_POWER_MODE power_mode){
4023     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4024     int err = 0;
4025     switch (hci_stack->state){
4026         case HCI_STATE_OFF:
4027             err = hci_power_control_state_off(power_mode);
4028             break;
4029         case HCI_STATE_INITIALIZING:
4030             err = hci_power_control_state_initializing(power_mode);
4031             break;
4032         case HCI_STATE_WORKING:
4033             err = hci_power_control_state_working(power_mode);
4034             break;
4035         case HCI_STATE_HALTING:
4036             err = hci_power_control_state_halting(power_mode);
4037             break;
4038         case HCI_STATE_FALLING_ASLEEP:
4039             err = hci_power_control_state_falling_asleep(power_mode);
4040             break;
4041         case HCI_STATE_SLEEPING:
4042             err = hci_power_control_state_sleeping(power_mode);
4043             break;
4044         default:
4045             btstack_assert(false);
4046             break;
4047     }
4048     if (err != 0){
4049         return err;
4050     }
4051 
4052     // create internal event
4053 	hci_emit_state();
4054 
4055 	// trigger next/first action
4056 	hci_run();
4057 
4058     return 0;
4059 }
4060 
4061 
4062 static void hci_halting_run(void){
4063 
4064     log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4065 
4066     hci_connection_t * connection;
4067 
4068     switch (hci_stack->substate) {
4069         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4070             case HCI_HALTING_DISCONNECT_ALL_TIMER:
4071 
4072 #ifdef ENABLE_BLE
4073 #ifdef ENABLE_LE_CENTRAL
4074     hci_whitelist_free();
4075 #endif
4076 #endif
4077     // close all open connections
4078     connection = (hci_connection_t *) hci_stack->connections;
4079     if (connection) {
4080         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4081         if (!hci_can_send_command_packet_now()) return;
4082 
4083         // check state
4084         if (connection->state == SENT_DISCONNECT) return;
4085         connection->state = SENT_DISCONNECT;
4086 
4087         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4088 
4089         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4090         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4091 
4092         // ... which would be ignored anyway as we shutdown (free) the connection now
4093         hci_shutdown_connection(connection);
4094 
4095         // finally, send the disconnect command
4096         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4097         return;
4098     }
4099 
4100     btstack_run_loop_remove_timer(&hci_stack->timeout);
4101 
4102     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER) {
4103         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4104         log_info("HCI_STATE_HALTING: wait 50 ms");
4105         hci_stack->substate = HCI_HALTING_W4_TIMER;
4106         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4107         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4108         btstack_run_loop_add_timer(&hci_stack->timeout);
4109         break;
4110     }
4111 
4112     /* fall through */
4113 
4114     case HCI_HALTING_CLOSE:
4115         // close left over connections (that had not been properly closed before)
4116         hci_discard_connections();
4117 
4118         log_info("HCI_STATE_HALTING, calling off");
4119 
4120         // switch mode
4121         hci_power_control_off();
4122 
4123         log_info("HCI_STATE_HALTING, emitting state");
4124         hci_emit_state();
4125         log_info("HCI_STATE_HALTING, done");
4126         break;
4127 
4128         case HCI_HALTING_W4_TIMER:
4129             // keep waiting
4130 
4131             break;
4132         default:
4133             break;
4134     }
4135 };
4136 
4137 static void hci_falling_asleep_run(void){
4138     hci_connection_t * connection;
4139     switch(hci_stack->substate) {
4140         case HCI_FALLING_ASLEEP_DISCONNECT:
4141             log_info("HCI_STATE_FALLING_ASLEEP");
4142             // close all open connections
4143             connection =  (hci_connection_t *) hci_stack->connections;
4144             if (connection){
4145 
4146                 // send disconnect
4147                 if (!hci_can_send_command_packet_now()) return;
4148 
4149                 log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4150                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4151 
4152                 // send disconnected event right away - causes higher layer connections to get closed, too.
4153                 hci_shutdown_connection(connection);
4154                 return;
4155             }
4156 
4157             if (hci_classic_supported()){
4158                 // disable page and inquiry scan
4159                 if (!hci_can_send_command_packet_now()) return;
4160 
4161                 log_info("HCI_STATE_HALTING, disabling inq scans");
4162                 hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4163 
4164                 // continue in next sub state
4165                 hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4166                 break;
4167             }
4168 
4169             /* fall through */
4170 
4171             case HCI_FALLING_ASLEEP_COMPLETE:
4172                 log_info("HCI_STATE_HALTING, calling sleep");
4173                 // switch mode
4174                 hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4175                 hci_emit_state();
4176                 break;
4177 
4178                 default:
4179                     break;
4180     }
4181 }
4182 
4183 #ifdef ENABLE_CLASSIC
4184 
4185 static void hci_update_scan_enable(void){
4186     // 2 = page scan, 1 = inq scan
4187     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4188     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4189     hci_run();
4190 }
4191 
4192 void gap_discoverable_control(uint8_t enable){
4193     if (enable) enable = 1; // normalize argument
4194 
4195     if (hci_stack->discoverable == enable){
4196         hci_emit_discoverable_enabled(hci_stack->discoverable);
4197         return;
4198     }
4199 
4200     hci_stack->discoverable = enable;
4201     hci_update_scan_enable();
4202 }
4203 
4204 void gap_connectable_control(uint8_t enable){
4205     if (enable) enable = 1; // normalize argument
4206 
4207     // don't emit event
4208     if (hci_stack->connectable == enable) return;
4209 
4210     hci_stack->connectable = enable;
4211     hci_update_scan_enable();
4212 }
4213 #endif
4214 
4215 void gap_local_bd_addr(bd_addr_t address_buffer){
4216     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4217 }
4218 
4219 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4220 static void hci_host_num_completed_packets(void){
4221 
4222     // create packet manually as arrays are not supported and num_commands should not get reduced
4223     hci_reserve_packet_buffer();
4224     uint8_t * packet = hci_get_outgoing_packet_buffer();
4225 
4226     uint16_t size = 0;
4227     uint16_t num_handles = 0;
4228     packet[size++] = 0x35;
4229     packet[size++] = 0x0c;
4230     size++;  // skip param len
4231     size++;  // skip num handles
4232 
4233     // add { handle, packets } entries
4234     btstack_linked_item_t * it;
4235     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4236         hci_connection_t * connection = (hci_connection_t *) it;
4237         if (connection->num_packets_completed){
4238             little_endian_store_16(packet, size, connection->con_handle);
4239             size += 2;
4240             little_endian_store_16(packet, size, connection->num_packets_completed);
4241             size += 2;
4242             //
4243             num_handles++;
4244             connection->num_packets_completed = 0;
4245         }
4246     }
4247 
4248     packet[2] = size - 3;
4249     packet[3] = num_handles;
4250 
4251     hci_stack->host_completed_packets = 0;
4252 
4253     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4254     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4255 
4256     // release packet buffer for synchronous transport implementations
4257     if (hci_transport_synchronous()){
4258         hci_release_packet_buffer();
4259         hci_emit_transport_packet_sent();
4260     }
4261 }
4262 #endif
4263 
4264 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4265     UNUSED(ds);
4266     hci_stack->substate = HCI_HALTING_CLOSE;
4267     // allow packet handlers to defer final shutdown
4268     hci_emit_state();
4269     hci_run();
4270 }
4271 
4272 static bool hci_run_acl_fragments(void){
4273     if (hci_stack->acl_fragmentation_total_size > 0u) {
4274         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4275         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4276         if (connection) {
4277             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4278                 hci_send_acl_packet_fragments(connection);
4279                 return true;
4280             }
4281         } else {
4282             // connection gone -> discard further fragments
4283             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4284             hci_stack->acl_fragmentation_total_size = 0;
4285             hci_stack->acl_fragmentation_pos = 0;
4286         }
4287     }
4288     return false;
4289 }
4290 
4291 #ifdef ENABLE_CLASSIC
4292 static bool hci_run_general_gap_classic(void){
4293 
4294     // assert stack is working and classic is active
4295     if (hci_classic_supported() == false)      return false;
4296     if (hci_stack->state != HCI_STATE_WORKING) return false;
4297 
4298     // decline incoming connections
4299     if (hci_stack->decline_reason){
4300         uint8_t reason = hci_stack->decline_reason;
4301         hci_stack->decline_reason = 0;
4302         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4303         return true;
4304     }
4305 
4306     if (hci_stack->gap_tasks != 0){
4307         hci_run_gap_tasks_classic();
4308         return true;
4309     }
4310 
4311     // start/stop inquiry
4312     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4313         uint8_t duration = hci_stack->inquiry_state;
4314         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4315         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4316         return true;
4317     }
4318     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4319         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4320         hci_send_cmd(&hci_inquiry_cancel);
4321         return true;
4322     }
4323     // remote name request
4324     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4325         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4326         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4327                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4328         return true;
4329     }
4330 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4331     // Local OOB data
4332     if (hci_stack->classic_read_local_oob_data){
4333         hci_stack->classic_read_local_oob_data = false;
4334         if (hci_stack->local_supported_commands[1] & 0x10u){
4335             hci_send_cmd(&hci_read_local_extended_oob_data);
4336         } else {
4337             hci_send_cmd(&hci_read_local_oob_data);
4338         }
4339     }
4340 #endif
4341     // pairing
4342     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4343         uint8_t state = hci_stack->gap_pairing_state;
4344         uint8_t pin_code[16];
4345         switch (state){
4346             case GAP_PAIRING_STATE_SEND_PIN:
4347                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4348                 memset(pin_code, 0, 16);
4349                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4350                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4351                 break;
4352             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4353                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4354                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4355                 break;
4356             case GAP_PAIRING_STATE_SEND_PASSKEY:
4357                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4358                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4359                 break;
4360             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4361                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4362                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4363                 break;
4364             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4365                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4366                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4367                 break;
4368             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4369                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4370                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4371                 break;
4372             default:
4373                 break;
4374         }
4375         return true;
4376     }
4377     return false;
4378 }
4379 #endif
4380 
4381 #ifdef ENABLE_BLE
4382 static bool hci_run_general_gap_le(void){
4383 
4384     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4385 
4386     if (hci_stack->state != HCI_STATE_WORKING) return false;
4387     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4388 
4389 
4390     // Phase 1: collect what to stop
4391 
4392     bool scanning_stop = false;
4393     bool connecting_stop = false;
4394     bool advertising_stop = false;
4395 
4396 #ifndef ENABLE_LE_CENTRAL
4397     UNUSED(scanning_stop);
4398     UNUSED(connecting_stop);
4399 #endif
4400 #ifndef ENABLE_LE_PERIPHERAL
4401     UNUSED(advertising_stop);
4402 #endif
4403 
4404     // check if own address changes
4405     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4406 
4407     // check if whitelist needs modification
4408     bool whitelist_modification_pending = false;
4409     btstack_linked_list_iterator_t lit;
4410     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4411     while (btstack_linked_list_iterator_has_next(&lit)){
4412         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4413         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4414             whitelist_modification_pending = true;
4415             break;
4416         }
4417     }
4418     // check if resolving list needs modification
4419     bool resolving_list_modification_pending = false;
4420 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4421     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4422 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4423         resolving_list_modification_pending = true;
4424     }
4425 #endif
4426 
4427 #ifdef ENABLE_LE_CENTRAL
4428     // scanning control
4429     if (hci_stack->le_scanning_active) {
4430         // stop if:
4431         // - parameter change required
4432         // - it's disabled
4433         // - whitelist change required but used for scanning
4434         // - resolving list modified
4435         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4436         if ((hci_stack->le_scanning_param_update) ||
4437             !hci_stack->le_scanning_enabled ||
4438             scanning_uses_whitelist ||
4439             resolving_list_modification_pending){
4440 
4441             scanning_stop = true;
4442         }
4443     }
4444 #endif
4445 
4446 #ifdef ENABLE_LE_CENTRAL
4447     // connecting control
4448     bool connecting_with_whitelist;
4449     switch (hci_stack->le_connecting_state){
4450         case LE_CONNECTING_DIRECT:
4451         case LE_CONNECTING_WHITELIST:
4452             // stop connecting if:
4453             // - connecting uses white and whitelist modification pending
4454             // - if it got disabled
4455             // - resolving list modified
4456             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4457             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4458                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4459                 resolving_list_modification_pending) {
4460 
4461                 connecting_stop = true;
4462             }
4463             break;
4464         default:
4465             break;
4466     }
4467 #endif
4468 
4469 #ifdef ENABLE_LE_PERIPHERAL
4470     // le advertisement control
4471     if (hci_stack->le_advertisements_active){
4472         // stop if:
4473         // - parameter change required
4474         // - random address used in advertising and changes
4475         // - it's disabled
4476         // - whitelist change required but used for advertisement filter policy
4477         // - resolving list modified
4478         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4479         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4480         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4481         if (advertising_change ||
4482             (advertising_uses_random_address && random_address_change) ||
4483             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4484             (advertising_uses_whitelist && whitelist_modification_pending) ||
4485             resolving_list_modification_pending) {
4486 
4487             advertising_stop = true;
4488         }
4489     }
4490 #endif
4491 
4492 
4493     // Phase 2: stop everything that should be off during modifications
4494 
4495 #ifdef ENABLE_LE_CENTRAL
4496     if (scanning_stop){
4497         hci_stack->le_scanning_active = false;
4498         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4499         return true;
4500     }
4501 #endif
4502 
4503 #ifdef ENABLE_LE_CENTRAL
4504     if (connecting_stop){
4505         hci_send_cmd(&hci_le_create_connection_cancel);
4506         return true;
4507     }
4508 #endif
4509 
4510 #ifdef ENABLE_LE_PERIPHERAL
4511     if (advertising_stop){
4512         hci_stack->le_advertisements_active = false;
4513         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4514         return true;
4515     }
4516 #endif
4517 
4518     // Phase 3: modify
4519 
4520     if (random_address_change){
4521         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4522         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4523         return true;
4524     }
4525 
4526 #ifdef ENABLE_LE_CENTRAL
4527     if (hci_stack->le_scanning_param_update){
4528         hci_stack->le_scanning_param_update = false;
4529         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4530                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4531         return true;
4532     }
4533 #endif
4534 
4535 #ifdef ENABLE_LE_PERIPHERAL
4536     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4537         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4538         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4539         hci_send_cmd(&hci_le_set_advertising_parameters,
4540                      hci_stack->le_advertisements_interval_min,
4541                      hci_stack->le_advertisements_interval_max,
4542                      hci_stack->le_advertisements_type,
4543                      hci_stack->le_advertisements_own_addr_type,
4544                      hci_stack->le_advertisements_direct_address_type,
4545                      hci_stack->le_advertisements_direct_address,
4546                      hci_stack->le_advertisements_channel_map,
4547                      hci_stack->le_advertisements_filter_policy);
4548         return true;
4549     }
4550     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4551         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4552         uint8_t adv_data_clean[31];
4553         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4554         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4555                      hci_stack->le_advertisements_data_len);
4556         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4557         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4558         return true;
4559     }
4560     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4561         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4562         uint8_t scan_data_clean[31];
4563         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4564         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4565                      hci_stack->le_scan_response_data_len);
4566         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4567         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4568         return true;
4569     }
4570 #endif
4571 
4572 
4573 #ifdef ENABLE_LE_CENTRAL
4574     // if connect with whitelist was active and is not cancelled yet, wait until next time
4575     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4576 #endif
4577 
4578     // LE Whitelist Management
4579     if (whitelist_modification_pending){
4580         // add/remove entries
4581         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4582         while (btstack_linked_list_iterator_has_next(&lit)){
4583             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4584 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4585 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4586 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4587 				return true;
4588 			}
4589             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4590 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4591                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4592                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4593                 return true;
4594             }
4595             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4596 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4597 				btstack_memory_whitelist_entry_free(entry);
4598             }
4599         }
4600     }
4601 
4602 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4603     // LE Resolving List Management
4604     if (resolving_list_supported) {
4605 		uint16_t i;
4606 		switch (hci_stack->le_resolving_list_state) {
4607 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4608 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4609 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4610 				return true;
4611 			case LE_RESOLVING_LIST_READ_SIZE:
4612 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4613 				hci_send_cmd(&hci_le_read_resolving_list_size);
4614 				return true;
4615 			case LE_RESOLVING_LIST_SEND_CLEAR:
4616 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4617 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4618 							  sizeof(hci_stack->le_resolving_list_add_entries));
4619 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4620 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4621 				hci_send_cmd(&hci_le_clear_resolving_list);
4622 				return true;
4623 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4624 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4625 					uint8_t offset = i >> 3;
4626 					uint8_t mask = 1 << (i & 7);
4627 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4628 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4629 					bd_addr_t peer_identity_addreses;
4630 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4631 					sm_key_t peer_irk;
4632 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4633 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4634 
4635 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4636 					// trigger whitelist entry 'update' (work around for controller bug)
4637 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4638 					while (btstack_linked_list_iterator_has_next(&lit)) {
4639 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4640 						if (entry->address_type != peer_identity_addr_type) continue;
4641 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4642 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4643 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4644 					}
4645 #endif
4646 
4647 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4648 								 peer_identity_addreses);
4649 					return true;
4650 				}
4651 
4652 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4653 
4654 				/* fall through */
4655 
4656 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4657 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4658 					uint8_t offset = i >> 3;
4659 					uint8_t mask = 1 << (i & 7);
4660 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4661 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4662 					bd_addr_t peer_identity_addreses;
4663 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4664 					sm_key_t peer_irk;
4665 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4666 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4667 					const uint8_t *local_irk = gap_get_persistent_irk();
4668 					// command uses format specifier 'P' that stores 16-byte value without flip
4669 					uint8_t local_irk_flipped[16];
4670 					uint8_t peer_irk_flipped[16];
4671 					reverse_128(local_irk, local_irk_flipped);
4672 					reverse_128(peer_irk, peer_irk_flipped);
4673 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4674 								 peer_irk_flipped, local_irk_flipped);
4675 					return true;
4676 				}
4677 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4678 				break;
4679 
4680 			default:
4681 				break;
4682 		}
4683 	}
4684     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4685 #endif
4686 
4687     // Phase 4: restore state
4688 
4689 #ifdef ENABLE_LE_CENTRAL
4690     // re-start scanning
4691     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4692         hci_stack->le_scanning_active = true;
4693         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4694         return true;
4695     }
4696 #endif
4697 
4698 #ifdef ENABLE_LE_CENTRAL
4699     // re-start connecting
4700     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4701         bd_addr_t null_addr;
4702         memset(null_addr, 0, 6);
4703         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4704         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4705         hci_send_cmd(&hci_le_create_connection,
4706                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4707                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4708                      1,         // use whitelist
4709                      0,         // peer address type
4710                      null_addr, // peer bd addr
4711                      hci_stack->le_connection_own_addr_type,   // our addr type:
4712                      hci_stack->le_connection_interval_min,    // conn interval min
4713                      hci_stack->le_connection_interval_max,    // conn interval max
4714                      hci_stack->le_connection_latency,         // conn latency
4715                      hci_stack->le_supervision_timeout,        // conn latency
4716                      hci_stack->le_minimum_ce_length,          // min ce length
4717                      hci_stack->le_maximum_ce_length           // max ce length
4718         );
4719         return true;
4720     }
4721 #endif
4722 
4723 #ifdef ENABLE_LE_PERIPHERAL
4724     // re-start advertising
4725     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4726         // check if advertisements should be enabled given
4727         hci_stack->le_advertisements_active = true;
4728         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4729         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4730         return true;
4731     }
4732 #endif
4733 
4734     return false;
4735 }
4736 #endif
4737 
4738 static bool hci_run_general_pending_commands(void){
4739     btstack_linked_item_t * it;
4740     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4741         hci_connection_t * connection = (hci_connection_t *) it;
4742 
4743         switch(connection->state){
4744             case SEND_CREATE_CONNECTION:
4745                 switch(connection->address_type){
4746 #ifdef ENABLE_CLASSIC
4747                     case BD_ADDR_TYPE_ACL:
4748                         log_info("sending hci_create_connection");
4749                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4750                         break;
4751 #endif
4752                     default:
4753 #ifdef ENABLE_BLE
4754 #ifdef ENABLE_LE_CENTRAL
4755                         log_info("sending hci_le_create_connection");
4756                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4757                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4758                         hci_send_cmd(&hci_le_create_connection,
4759                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4760                                      hci_stack->le_connection_scan_window,      // conn scan windows
4761                                      0,         // don't use whitelist
4762                                      connection->address_type, // peer address type
4763                                      connection->address,      // peer bd addr
4764                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4765                                      hci_stack->le_connection_interval_min,    // conn interval min
4766                                      hci_stack->le_connection_interval_max,    // conn interval max
4767                                      hci_stack->le_connection_latency,         // conn latency
4768                                      hci_stack->le_supervision_timeout,        // conn latency
4769                                      hci_stack->le_minimum_ce_length,          // min ce length
4770                                      hci_stack->le_maximum_ce_length          // max ce length
4771                         );
4772                         connection->state = SENT_CREATE_CONNECTION;
4773 #endif
4774 #endif
4775                         break;
4776                 }
4777                 return true;
4778 
4779 #ifdef ENABLE_CLASSIC
4780             case RECEIVED_CONNECTION_REQUEST:
4781                 connection->role  = HCI_ROLE_SLAVE;
4782                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4783                     log_info("sending hci_accept_connection_request");
4784                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4785                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4786                 }
4787                 return true;
4788 #endif
4789 
4790 #ifdef ENABLE_BLE
4791 #ifdef ENABLE_LE_CENTRAL
4792             case SEND_CANCEL_CONNECTION:
4793                 connection->state = SENT_CANCEL_CONNECTION;
4794                 hci_send_cmd(&hci_le_create_connection_cancel);
4795                 return true;
4796 #endif
4797 #endif
4798             case SEND_DISCONNECT:
4799                 connection->state = SENT_DISCONNECT;
4800                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4801                 return true;
4802 
4803             default:
4804                 break;
4805         }
4806 
4807         // no further commands if connection is about to get shut down
4808         if (connection->state == SENT_DISCONNECT) continue;
4809 
4810         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4811             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4812             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4813             return true;
4814         }
4815 
4816 #ifdef ENABLE_CLASSIC
4817 
4818         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4819             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4820             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4821             return true;
4822         }
4823 
4824         // Handling link key request requires remote supported features
4825         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4826             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4827             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4828 
4829             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4830             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4831             if (have_link_key && security_level_sufficient){
4832                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4833             } else {
4834                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4835             }
4836             return true;
4837         }
4838 
4839         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4840             log_info("denying to pin request");
4841             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4842             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4843             return true;
4844         }
4845 
4846         // security assessment requires remote features
4847         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4848             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4849             hci_ssp_assess_security_on_io_cap_request(connection);
4850             // 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
4851         }
4852 
4853         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4854             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4855             // set authentication requirements:
4856             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4857             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4858             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4859             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4860                 authreq |= 1;
4861             }
4862             bool bonding = hci_stack->bondable;
4863             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4864                 // if we have received IO Cap Response, we're in responder role
4865                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4866                 if (bonding && !remote_bonding){
4867                     log_info("Remote not bonding, dropping local flag");
4868                     bonding = false;
4869                 }
4870             }
4871             if (bonding){
4872                 if (connection->bonding_flags & BONDING_DEDICATED){
4873                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4874                 } else {
4875                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4876                 }
4877             }
4878             uint8_t have_oob_data = 0;
4879 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4880             if (connection->classic_oob_c_192 != NULL){
4881                     have_oob_data |= 1;
4882             }
4883             if (connection->classic_oob_c_256 != NULL){
4884                 have_oob_data |= 2;
4885             }
4886 #endif
4887             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4888             return true;
4889         }
4890 
4891         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4892             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4893             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4894             return true;
4895         }
4896 
4897 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4898         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4899             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4900             const uint8_t zero[16] = { 0 };
4901             const uint8_t * r_192 = zero;
4902             const uint8_t * c_192 = zero;
4903             const uint8_t * r_256 = zero;
4904             const uint8_t * c_256 = zero;
4905             // verify P-256 OOB
4906             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4907                 c_256 = connection->classic_oob_c_256;
4908                 if (connection->classic_oob_r_256 != NULL) {
4909                     r_256 = connection->classic_oob_r_256;
4910                 }
4911             }
4912             // verify P-192 OOB
4913             if ((connection->classic_oob_c_192 != NULL)) {
4914                 c_192 = connection->classic_oob_c_192;
4915                 if (connection->classic_oob_r_192 != NULL) {
4916                     r_192 = connection->classic_oob_r_192;
4917                 }
4918             }
4919 
4920             // assess security
4921             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4922             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4923             if (need_level_4 && !can_reach_level_4){
4924                 log_info("Level 4 required, but not possible -> abort");
4925                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4926                 // send oob negative reply
4927                 c_256 = NULL;
4928                 c_192 = NULL;
4929             }
4930 
4931             // Reply
4932             if (c_256 != zero) {
4933                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4934             } else if (c_192 != zero){
4935                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4936             } else {
4937                 hci_stack->classic_oob_con_handle = connection->con_handle;
4938                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4939             }
4940             return true;
4941         }
4942 #endif
4943 
4944         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4945             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4946             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4947             return true;
4948         }
4949 
4950         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4951             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4952             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4953             return true;
4954         }
4955 
4956         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4957             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4958             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4959             return true;
4960         }
4961 
4962         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4963             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4964             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4965             connection->state = SENT_DISCONNECT;
4966             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4967             return true;
4968         }
4969 
4970         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4971             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4972             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4973             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4974             return true;
4975         }
4976 
4977         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4978             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4979             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4980             return true;
4981         }
4982 
4983         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4984             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4985             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4986             return true;
4987         }
4988 
4989         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4990             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4991             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4992             return true;
4993         }
4994 
4995         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4996             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4997             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4998             return true;
4999         }
5000 
5001         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
5002             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
5003             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
5004             return true;
5005         }
5006 #endif
5007 
5008         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
5009             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
5010 #ifdef ENABLE_CLASSIC
5011             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
5012 #endif
5013             if (connection->state != SENT_DISCONNECT){
5014                 connection->state = SENT_DISCONNECT;
5015                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
5016                 return true;
5017             }
5018         }
5019 
5020 #ifdef ENABLE_CLASSIC
5021         uint16_t sniff_min_interval;
5022         switch (connection->sniff_min_interval){
5023             case 0:
5024                 break;
5025             case 0xffff:
5026                 connection->sniff_min_interval = 0;
5027                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
5028                 return true;
5029             default:
5030                 sniff_min_interval = connection->sniff_min_interval;
5031                 connection->sniff_min_interval = 0;
5032                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
5033                 return true;
5034         }
5035 
5036         if (connection->sniff_subrating_max_latency != 0xffff){
5037             uint16_t max_latency = connection->sniff_subrating_max_latency;
5038             connection->sniff_subrating_max_latency = 0;
5039             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
5040             return true;
5041         }
5042 
5043         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
5044             uint8_t service_type = (uint8_t) connection->qos_service_type;
5045             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
5046             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);
5047             return true;
5048         }
5049 
5050         if (connection->request_role != HCI_ROLE_INVALID){
5051             hci_role_t role = connection->request_role;
5052             connection->request_role = HCI_ROLE_INVALID;
5053             hci_send_cmd(&hci_switch_role_command, connection->address, role);
5054             return true;
5055         }
5056 #endif
5057 
5058 #ifdef ENABLE_BLE
5059         switch (connection->le_con_parameter_update_state){
5060             // response to L2CAP CON PARAMETER UPDATE REQUEST
5061             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
5062                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5063                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
5064                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5065                              0x0000, 0xffff);
5066                 return true;
5067             case CON_PARAMETER_UPDATE_REPLY:
5068                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5069                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
5070                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5071                              0x0000, 0xffff);
5072                 return true;
5073             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
5074                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5075                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
5076                 return true;
5077             default:
5078                 break;
5079         }
5080         if (connection->le_phy_update_all_phys != 0xffu){
5081             uint8_t all_phys = connection->le_phy_update_all_phys;
5082             connection->le_phy_update_all_phys = 0xff;
5083             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);
5084             return true;
5085         }
5086 #endif
5087     }
5088     return false;
5089 }
5090 
5091 static void hci_run(void){
5092 
5093     // stack state sub statemachines
5094     // halting needs to be called even if we cannot send command packet now
5095     switch (hci_stack->state) {
5096         case HCI_STATE_INITIALIZING:
5097             hci_initializing_run();
5098             break;
5099         case HCI_STATE_HALTING:
5100             hci_halting_run();
5101             break;
5102         case HCI_STATE_FALLING_ASLEEP:
5103             hci_falling_asleep_run();
5104             break;
5105         default:
5106             break;
5107     }
5108 
5109     bool done;
5110 
5111     // send continuation fragments first, as they block the prepared packet buffer
5112     done = hci_run_acl_fragments();
5113     if (done) return;
5114 
5115 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
5116     // send host num completed packets next as they don't require num_cmd_packets > 0
5117     if (!hci_can_send_comand_packet_transport()) return;
5118     if (hci_stack->host_completed_packets){
5119         hci_host_num_completed_packets();
5120         return;
5121     }
5122 #endif
5123 
5124     if (!hci_can_send_command_packet_now()) return;
5125 
5126     // global/non-connection oriented commands
5127 
5128 
5129 #ifdef ENABLE_CLASSIC
5130     // general gap classic
5131     done = hci_run_general_gap_classic();
5132     if (done) return;
5133 #endif
5134 
5135 #ifdef ENABLE_BLE
5136     // general gap le
5137     done = hci_run_general_gap_le();
5138     if (done) return;
5139 #endif
5140 
5141     // send pending HCI commands
5142     hci_run_general_pending_commands();
5143 }
5144 
5145 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5146     // house-keeping
5147 
5148 #ifdef ENABLE_CLASSIC
5149     bd_addr_t addr;
5150     hci_connection_t * conn;
5151 #endif
5152 #ifdef ENABLE_LE_CENTRAL
5153     uint8_t initiator_filter_policy;
5154 #endif
5155 
5156     uint16_t opcode = little_endian_read_16(packet, 0);
5157     switch (opcode) {
5158         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5159             hci_stack->loopback_mode = packet[3];
5160             break;
5161 
5162 #ifdef ENABLE_CLASSIC
5163         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5164             reverse_bd_addr(&packet[3], addr);
5165             log_info("Create_connection to %s", bd_addr_to_str(addr));
5166 
5167             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5168             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5169                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5170                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5171             }
5172 
5173             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5174             if (!conn) {
5175                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5176                 if (!conn) {
5177                     // notify client that alloc failed
5178                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5179                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5180                 }
5181                 conn->state = SEND_CREATE_CONNECTION;
5182                 conn->role  = HCI_ROLE_MASTER;
5183             }
5184 
5185             conn->con_handle = HCI_CON_HANDLE_INVALID;
5186             conn->role = HCI_ROLE_INVALID;
5187 
5188             log_info("conn state %u", conn->state);
5189             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5190             switch (conn->state) {
5191                 // if connection active exists
5192                 case OPEN:
5193                     // and OPEN, emit connection complete command
5194                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5195                     // packet not sent to controller
5196                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5197                 case RECEIVED_DISCONNECTION_COMPLETE:
5198                     // create connection triggered in disconnect complete event, let's do it now
5199                     break;
5200                 case SEND_CREATE_CONNECTION:
5201                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5202                     break;
5203                 default:
5204                     // otherwise, just ignore as it is already in the open process
5205                     // packet not sent to controller
5206                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5207             }
5208             conn->state = SENT_CREATE_CONNECTION;
5209 
5210             // track outgoing connection
5211             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5212             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5213             break;
5214 
5215 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5216         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5217             // setup_synchronous_connection? Voice setting at offset 22
5218             // TODO: compare to current setting if sco connection already active
5219             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5220             break;
5221         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5222             // accept_synchronous_connection? Voice setting at offset 18
5223             // TODO: compare to current setting if sco connection already active
5224             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5225             break;
5226 #endif
5227 #endif
5228 
5229 #ifdef ENABLE_BLE
5230 #ifdef ENABLE_LE_CENTRAL
5231         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5232             // white list used?
5233             initiator_filter_policy = packet[7];
5234             switch (initiator_filter_policy) {
5235                 case 0:
5236                     // whitelist not used
5237                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5238                     break;
5239                 case 1:
5240                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5241                     break;
5242                 default:
5243                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5244                     break;
5245             }
5246             // track outgoing connection
5247             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5248             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5249             break;
5250         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5251             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5252             break;
5253 #endif
5254 #endif
5255         default:
5256             break;
5257     }
5258 
5259     hci_stack->num_cmd_packets--;
5260 
5261     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5262     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5263     if (err != 0){
5264         return ERROR_CODE_HARDWARE_FAILURE;
5265     }
5266     return ERROR_CODE_SUCCESS;
5267 }
5268 
5269 // disconnect because of security block
5270 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5271     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5272     if (!connection) return;
5273     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5274 }
5275 
5276 
5277 // Configure Secure Simple Pairing
5278 
5279 #ifdef ENABLE_CLASSIC
5280 
5281 // enable will enable SSP during init
5282 void gap_ssp_set_enable(int enable){
5283     hci_stack->ssp_enable = enable;
5284 }
5285 
5286 static int hci_local_ssp_activated(void){
5287     return gap_ssp_supported() && hci_stack->ssp_enable;
5288 }
5289 
5290 // if set, BTstack will respond to io capability request using authentication requirement
5291 void gap_ssp_set_io_capability(int io_capability){
5292     hci_stack->ssp_io_capability = io_capability;
5293 }
5294 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5295     hci_stack->ssp_authentication_requirement = authentication_requirement;
5296 }
5297 
5298 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5299 void gap_ssp_set_auto_accept(int auto_accept){
5300     hci_stack->ssp_auto_accept = auto_accept;
5301 }
5302 
5303 void gap_secure_connections_enable(bool enable){
5304     hci_stack->secure_connections_enable = enable;
5305 }
5306 
5307 #endif
5308 
5309 // va_list part of hci_send_cmd
5310 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5311     if (!hci_can_send_command_packet_now()){
5312         log_error("hci_send_cmd called but cannot send packet now");
5313         return ERROR_CODE_COMMAND_DISALLOWED;
5314     }
5315 
5316     // for HCI INITIALIZATION
5317     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5318     hci_stack->last_cmd_opcode = cmd->opcode;
5319 
5320     hci_reserve_packet_buffer();
5321     uint8_t * packet = hci_stack->hci_packet_buffer;
5322     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5323     uint8_t status = hci_send_cmd_packet(packet, size);
5324 
5325     // release packet buffer on error or for synchronous transport implementations
5326     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5327         hci_release_packet_buffer();
5328         hci_emit_transport_packet_sent();
5329     }
5330 
5331     return status;
5332 }
5333 
5334 /**
5335  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5336  */
5337 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5338     va_list argptr;
5339     va_start(argptr, cmd);
5340     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5341     va_end(argptr);
5342     return status;
5343 }
5344 
5345 // Create various non-HCI events.
5346 // TODO: generalize, use table similar to hci_create_command
5347 
5348 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5349     // dump packet
5350     if (dump) {
5351         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5352     }
5353 
5354     // dispatch to all event handlers
5355     btstack_linked_list_iterator_t it;
5356     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5357     while (btstack_linked_list_iterator_has_next(&it)){
5358         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5359         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5360     }
5361 }
5362 
5363 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5364     if (!hci_stack->acl_packet_handler) return;
5365     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5366 }
5367 
5368 #ifdef ENABLE_CLASSIC
5369 static void hci_notify_if_sco_can_send_now(void){
5370     // notify SCO sender if waiting
5371     if (!hci_stack->sco_waiting_for_can_send_now) return;
5372     if (hci_can_send_sco_packet_now()){
5373         hci_stack->sco_waiting_for_can_send_now = 0;
5374         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5375         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5376         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5377     }
5378 }
5379 
5380 // parsing end emitting has been merged to reduce code size
5381 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5382     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5383 
5384     uint8_t * eir_data;
5385     ad_context_t context;
5386     const uint8_t * name;
5387     uint8_t         name_len;
5388 
5389     if (size < 3) return;
5390 
5391     int event_type = hci_event_packet_get_type(packet);
5392     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5393     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5394 
5395     switch (event_type){
5396         case HCI_EVENT_INQUIRY_RESULT:
5397         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5398             if (size != (3 + (num_responses * 14))) return;
5399             break;
5400         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5401             if (size != 257) return;
5402             if (num_responses != 1) return;
5403             break;
5404         default:
5405             return;
5406     }
5407 
5408     // event[1] is set at the end
5409     int i;
5410     for (i=0; i<num_responses;i++){
5411         memset(event, 0, sizeof(event));
5412         event[0] = GAP_EVENT_INQUIRY_RESULT;
5413         uint8_t event_size = 27;    // if name is not set by EIR
5414 
5415         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5416         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5417         (void)memcpy(&event[9],
5418                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5419                      3); // class of device
5420         (void)memcpy(&event[12],
5421                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5422                      2); // clock offset
5423 
5424         switch (event_type){
5425             case HCI_EVENT_INQUIRY_RESULT:
5426                 // 14,15,16,17 = 0, size 18
5427                 break;
5428             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5429                 event[14] = 1;
5430                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5431                 // 16,17 = 0, size 18
5432                 break;
5433             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5434                 event[14] = 1;
5435                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5436                 // EIR packets only contain a single inquiry response
5437                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5438                 name = NULL;
5439                 // Iterate over EIR data
5440                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5441                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5442                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5443                     const uint8_t * data = ad_iterator_get_data(&context);
5444                     // Prefer Complete Local Name over Shortened Local Name
5445                     switch (data_type){
5446                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5447                             if (name) continue;
5448                             /* fall through */
5449                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5450                             name = data;
5451                             name_len = data_size;
5452                             break;
5453                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5454                             if (data_size != 8) break;
5455                             event[16] = 1;
5456                             memcpy(&event[17], data, 8);
5457                             break;
5458                         default:
5459                             break;
5460                     }
5461                 }
5462                 if (name){
5463                     event[25] = 1;
5464                     // truncate name if needed
5465                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5466                     event[26] = len;
5467                     (void)memcpy(&event[27], name, len);
5468                     event_size += len;
5469                 }
5470                 break;
5471             default:
5472                 return;
5473         }
5474         event[1] = event_size - 2;
5475         hci_emit_event(event, event_size, 1);
5476     }
5477 }
5478 #endif
5479 
5480 void hci_emit_state(void){
5481     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5482     uint8_t event[3];
5483     event[0] = BTSTACK_EVENT_STATE;
5484     event[1] = sizeof(event) - 2u;
5485     event[2] = hci_stack->state;
5486     hci_emit_event(event, sizeof(event), 1);
5487 }
5488 
5489 #ifdef ENABLE_CLASSIC
5490 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5491     uint8_t event[13];
5492     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5493     event[1] = sizeof(event) - 2;
5494     event[2] = status;
5495     little_endian_store_16(event, 3, con_handle);
5496     reverse_bd_addr(address, &event[5]);
5497     event[11] = 1; // ACL connection
5498     event[12] = 0; // encryption disabled
5499     hci_emit_event(event, sizeof(event), 1);
5500 }
5501 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5502     if (disable_l2cap_timeouts) return;
5503     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5504     uint8_t event[4];
5505     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5506     event[1] = sizeof(event) - 2;
5507     little_endian_store_16(event, 2, conn->con_handle);
5508     hci_emit_event(event, sizeof(event), 1);
5509 }
5510 #endif
5511 
5512 #ifdef ENABLE_BLE
5513 #ifdef ENABLE_LE_CENTRAL
5514 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){
5515     uint8_t event[21];
5516     event[0] = HCI_EVENT_LE_META;
5517     event[1] = sizeof(event) - 2u;
5518     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5519     event[3] = status;
5520     little_endian_store_16(event, 4, con_handle);
5521     event[6] = 0; // TODO: role
5522     event[7] = address_type;
5523     reverse_bd_addr(address, &event[8]);
5524     little_endian_store_16(event, 14, 0); // interval
5525     little_endian_store_16(event, 16, 0); // latency
5526     little_endian_store_16(event, 18, 0); // supervision timeout
5527     event[20] = 0; // master clock accuracy
5528     hci_emit_event(event, sizeof(event), 1);
5529 }
5530 #endif
5531 #endif
5532 
5533 static void hci_emit_transport_packet_sent(void){
5534     // notify upper stack that it might be possible to send again
5535     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5536     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5537 }
5538 
5539 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5540     uint8_t event[6];
5541     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5542     event[1] = sizeof(event) - 2u;
5543     event[2] = 0; // status = OK
5544     little_endian_store_16(event, 3, con_handle);
5545     event[5] = reason;
5546     hci_emit_event(event, sizeof(event), 1);
5547 }
5548 
5549 static void hci_emit_nr_connections_changed(void){
5550     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5551     uint8_t event[3];
5552     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5553     event[1] = sizeof(event) - 2u;
5554     event[2] = nr_hci_connections();
5555     hci_emit_event(event, sizeof(event), 1);
5556 }
5557 
5558 static void hci_emit_hci_open_failed(void){
5559     log_info("BTSTACK_EVENT_POWERON_FAILED");
5560     uint8_t event[2];
5561     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5562     event[1] = sizeof(event) - 2u;
5563     hci_emit_event(event, sizeof(event), 1);
5564 }
5565 
5566 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5567     log_info("hci_emit_dedicated_bonding_result %u ", status);
5568     uint8_t event[9];
5569     int pos = 0;
5570     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5571     event[pos++] = sizeof(event) - 2u;
5572     event[pos++] = status;
5573     reverse_bd_addr(address, &event[pos]);
5574     hci_emit_event(event, sizeof(event), 1);
5575 }
5576 
5577 
5578 #ifdef ENABLE_CLASSIC
5579 
5580 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5581     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5582     uint8_t event[5];
5583     int pos = 0;
5584     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5585     event[pos++] = sizeof(event) - 2;
5586     little_endian_store_16(event, 2, con_handle);
5587     pos += 2;
5588     event[pos++] = level;
5589     hci_emit_event(event, sizeof(event), 1);
5590 }
5591 
5592 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5593     if (!connection) return LEVEL_0;
5594     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5595     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5596     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5597     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5598     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5599     // LEVEL 4 always requires 128 bit encrytion key size
5600     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5601         security_level = LEVEL_3;
5602     }
5603     return security_level;
5604 }
5605 
5606 static void hci_emit_discoverable_enabled(uint8_t enabled){
5607     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5608     uint8_t event[3];
5609     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5610     event[1] = sizeof(event) - 2;
5611     event[2] = enabled;
5612     hci_emit_event(event, sizeof(event), 1);
5613 }
5614 
5615 // query if remote side supports eSCO
5616 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5617     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5618     if (!connection) return false;
5619     return (connection->remote_supported_features[0] & 1) != 0;
5620 }
5621 
5622 static bool hci_ssp_supported(hci_connection_t * connection){
5623     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5624     return (connection->bonding_flags & mask) == mask;
5625 }
5626 
5627 // query if remote side supports SSP
5628 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5629     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5630     if (!connection) return false;
5631     return hci_ssp_supported(connection) ? 1 : 0;
5632 }
5633 
5634 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5635     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5636 }
5637 
5638 /**
5639  * Check if remote supported features query has completed
5640  */
5641 bool hci_remote_features_available(hci_con_handle_t handle){
5642     hci_connection_t * connection = hci_connection_for_handle(handle);
5643     if (!connection) return false;
5644     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5645 }
5646 
5647 /**
5648  * Trigger remote supported features query
5649  */
5650 
5651 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection){
5652     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) == 0){
5653         connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5654     }
5655 }
5656 
5657 void hci_remote_features_query(hci_con_handle_t con_handle){
5658     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5659     if (!connection) return;
5660     hci_trigger_remote_features_for_connection(connection);
5661     hci_run();
5662 }
5663 
5664 // GAP API
5665 /**
5666  * @bbrief enable/disable bonding. default is enabled
5667  * @praram enabled
5668  */
5669 void gap_set_bondable_mode(int enable){
5670     hci_stack->bondable = enable ? 1 : 0;
5671 }
5672 /**
5673  * @brief Get bondable mode.
5674  * @return 1 if bondable
5675  */
5676 int gap_get_bondable_mode(void){
5677     return hci_stack->bondable;
5678 }
5679 
5680 /**
5681  * @brief map link keys to security levels
5682  */
5683 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5684     switch (link_key_type){
5685         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5686             return LEVEL_4;
5687         case COMBINATION_KEY:
5688         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5689             return LEVEL_3;
5690         default:
5691             return LEVEL_2;
5692     }
5693 }
5694 
5695 /**
5696  * @brief map link keys to secure connection yes/no
5697  */
5698 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5699     switch (link_key_type){
5700         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5701         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5702             return 1;
5703         default:
5704             return 0;
5705     }
5706 }
5707 
5708 /**
5709  * @brief map link keys to authenticated
5710  */
5711 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5712     switch (link_key_type){
5713         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5714         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5715             return 1;
5716         default:
5717             return 0;
5718     }
5719 }
5720 
5721 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5722     log_info("gap_mitm_protection_required_for_security_level %u", level);
5723     return level > LEVEL_2;
5724 }
5725 
5726 /**
5727  * @brief get current security level
5728  */
5729 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5730     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5731     if (!connection) return LEVEL_0;
5732     return gap_security_level_for_connection(connection);
5733 }
5734 
5735 /**
5736  * @brief request connection to device to
5737  * @result GAP_AUTHENTICATION_RESULT
5738  */
5739 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5740     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5741     if (!connection){
5742         hci_emit_security_level(con_handle, LEVEL_0);
5743         return;
5744     }
5745 
5746     btstack_assert(hci_is_le_connection(connection) == false);
5747 
5748     // 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)
5749     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5750     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5751         requested_level = LEVEL_4;
5752     }
5753 
5754     gap_security_level_t current_level = gap_security_level(con_handle);
5755     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5756         requested_level, connection->requested_security_level, current_level);
5757 
5758     // authentication active if authentication request was sent or planned level > 0
5759     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5760     if (authentication_active){
5761         // authentication already active
5762         if (connection->requested_security_level < requested_level){
5763             // increase requested level as new level is higher
5764             // TODO: handle re-authentication when done
5765             connection->requested_security_level = requested_level;
5766         }
5767     } else {
5768         // no request active, notify if security sufficient
5769         if (requested_level <= current_level){
5770             hci_emit_security_level(con_handle, current_level);
5771             return;
5772         }
5773 
5774         // store request
5775         connection->requested_security_level = requested_level;
5776 
5777         // request remote features if not already active
5778         hci_remote_features_query(con_handle);
5779 
5780         // start to authenticate connection
5781         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5782         hci_run();
5783     }
5784 }
5785 
5786 /**
5787  * @brief start dedicated bonding with device. disconnect after bonding
5788  * @param device
5789  * @param request MITM protection
5790  * @result GAP_DEDICATED_BONDING_COMPLETE
5791  */
5792 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5793 
5794     // create connection state machine
5795     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5796 
5797     if (!connection){
5798         return BTSTACK_MEMORY_ALLOC_FAILED;
5799     }
5800 
5801     // delete linkn key
5802     gap_drop_link_key_for_bd_addr(device);
5803 
5804     // configure LEVEL_2/3, dedicated bonding
5805     connection->state = SEND_CREATE_CONNECTION;
5806     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5807     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5808     connection->bonding_flags = BONDING_DEDICATED;
5809 
5810     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5811 
5812     // handle: connnection failure (connection complete != ok)
5813     // handle: authentication failure
5814     // handle: disconnect on done
5815 
5816     hci_run();
5817 
5818     return 0;
5819 }
5820 
5821 void gap_set_local_name(const char * local_name){
5822     hci_stack->local_name = local_name;
5823     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5824     // also update EIR if not set by user
5825     if (hci_stack->eir_data == NULL){
5826         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5827     }
5828     hci_run();
5829 }
5830 #endif
5831 
5832 
5833 #ifdef ENABLE_BLE
5834 
5835 #ifdef ENABLE_LE_CENTRAL
5836 void gap_start_scan(void){
5837     hci_stack->le_scanning_enabled = true;
5838     hci_run();
5839 }
5840 
5841 void gap_stop_scan(void){
5842     hci_stack->le_scanning_enabled = false;
5843     hci_run();
5844 }
5845 
5846 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5847     hci_stack->le_scan_type          = scan_type;
5848     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5849     hci_stack->le_scan_interval      = scan_interval;
5850     hci_stack->le_scan_window        = scan_window;
5851     hci_stack->le_scanning_param_update = true;
5852     hci_run();
5853 }
5854 
5855 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5856     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5857 }
5858 
5859 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5860     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5861     if (!conn){
5862         // disallow if le connection is already outgoing
5863         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5864             log_error("le connection already active");
5865             return ERROR_CODE_COMMAND_DISALLOWED;
5866         }
5867 
5868         log_info("gap_connect: no connection exists yet, creating context");
5869         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5870         if (!conn){
5871             // notify client that alloc failed
5872             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5873             log_info("gap_connect: failed to alloc hci_connection_t");
5874             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5875         }
5876 
5877         // set le connecting state
5878         if (hci_is_le_connection_type(addr_type)){
5879             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5880         }
5881 
5882         conn->state = SEND_CREATE_CONNECTION;
5883         log_info("gap_connect: send create connection next");
5884         hci_run();
5885         return ERROR_CODE_SUCCESS;
5886     }
5887 
5888     if (!hci_is_le_connection(conn) ||
5889         (conn->state == SEND_CREATE_CONNECTION) ||
5890         (conn->state == SENT_CREATE_CONNECTION)) {
5891         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5892         log_error("gap_connect: classic connection or connect is already being created");
5893         return GATT_CLIENT_IN_WRONG_STATE;
5894     }
5895 
5896     // check if connection was just disconnected
5897     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5898         log_info("gap_connect: send create connection (again)");
5899         conn->state = SEND_CREATE_CONNECTION;
5900         hci_run();
5901         return ERROR_CODE_SUCCESS;
5902     }
5903 
5904     log_info("gap_connect: context exists with state %u", conn->state);
5905     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5906     hci_run();
5907     return ERROR_CODE_SUCCESS;
5908 }
5909 
5910 // @assumption: only a single outgoing LE Connection exists
5911 static hci_connection_t * gap_get_outgoing_connection(void){
5912     btstack_linked_item_t *it;
5913     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5914         hci_connection_t * conn = (hci_connection_t *) it;
5915         if (!hci_is_le_connection(conn)) continue;
5916         switch (conn->state){
5917             case SEND_CREATE_CONNECTION:
5918             case SENT_CREATE_CONNECTION:
5919             case SENT_CANCEL_CONNECTION:
5920                 return conn;
5921             default:
5922                 break;
5923         };
5924     }
5925     return NULL;
5926 }
5927 
5928 uint8_t gap_connect_cancel(void){
5929     hci_connection_t * conn = gap_get_outgoing_connection();
5930     if (!conn) return 0;
5931     switch (conn->state){
5932         case SEND_CREATE_CONNECTION:
5933             // skip sending create connection and emit event instead
5934             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5935             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5936             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5937             btstack_memory_hci_connection_free( conn );
5938             break;
5939         case SENT_CREATE_CONNECTION:
5940             // request to send cancel connection
5941             conn->state = SEND_CANCEL_CONNECTION;
5942             hci_run();
5943             break;
5944         default:
5945             break;
5946     }
5947     return 0;
5948 }
5949 #endif
5950 
5951 #ifdef ENABLE_LE_CENTRAL
5952 /**
5953  * @brief Set connection parameters for outgoing connections
5954  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5955  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5956  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5957  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5958  * @param conn_latency, default: 4
5959  * @param supervision_timeout (unit: 10ms), default: 720 ms
5960  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5961  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5962  */
5963 
5964 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5965     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5966     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5967     hci_stack->le_connection_scan_interval = conn_scan_interval;
5968     hci_stack->le_connection_scan_window = conn_scan_window;
5969     hci_stack->le_connection_interval_min = conn_interval_min;
5970     hci_stack->le_connection_interval_max = conn_interval_max;
5971     hci_stack->le_connection_latency = conn_latency;
5972     hci_stack->le_supervision_timeout = supervision_timeout;
5973     hci_stack->le_minimum_ce_length = min_ce_length;
5974     hci_stack->le_maximum_ce_length = max_ce_length;
5975 }
5976 #endif
5977 
5978 /**
5979  * @brief Updates the connection parameters for a given LE connection
5980  * @param handle
5981  * @param conn_interval_min (unit: 1.25ms)
5982  * @param conn_interval_max (unit: 1.25ms)
5983  * @param conn_latency
5984  * @param supervision_timeout (unit: 10ms)
5985  * @return 0 if ok
5986  */
5987 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5988     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5989     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5990     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5991     connection->le_conn_interval_min = conn_interval_min;
5992     connection->le_conn_interval_max = conn_interval_max;
5993     connection->le_conn_latency = conn_latency;
5994     connection->le_supervision_timeout = supervision_timeout;
5995     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5996     hci_run();
5997     return 0;
5998 }
5999 
6000 /**
6001  * @brief Request an update of the connection parameter for a given LE connection
6002  * @param handle
6003  * @param conn_interval_min (unit: 1.25ms)
6004  * @param conn_interval_max (unit: 1.25ms)
6005  * @param conn_latency
6006  * @param supervision_timeout (unit: 10ms)
6007  * @return 0 if ok
6008  */
6009 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
6010     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
6011     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6012     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6013     connection->le_conn_interval_min = conn_interval_min;
6014     connection->le_conn_interval_max = conn_interval_max;
6015     connection->le_conn_latency = conn_latency;
6016     connection->le_supervision_timeout = supervision_timeout;
6017     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
6018     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
6019     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
6020     return 0;
6021 }
6022 
6023 #ifdef ENABLE_LE_PERIPHERAL
6024 
6025 /**
6026  * @brief Set Advertisement Data
6027  * @param advertising_data_length
6028  * @param advertising_data (max 31 octets)
6029  * @note data is not copied, pointer has to stay valid
6030  */
6031 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6032     hci_stack->le_advertisements_data_len = advertising_data_length;
6033     hci_stack->le_advertisements_data = advertising_data;
6034     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6035     hci_run();
6036 }
6037 
6038 /**
6039  * @brief Set Scan Response Data
6040  * @param advertising_data_length
6041  * @param advertising_data (max 31 octets)
6042  * @note data is not copied, pointer has to stay valid
6043  */
6044 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6045     hci_stack->le_scan_response_data_len = scan_response_data_length;
6046     hci_stack->le_scan_response_data = scan_response_data;
6047     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6048     hci_run();
6049 }
6050 
6051 /**
6052  * @brief Set Advertisement Parameters
6053  * @param adv_int_min
6054  * @param adv_int_max
6055  * @param adv_type
6056  * @param direct_address_type
6057  * @param direct_address
6058  * @param channel_map
6059  * @param filter_policy
6060  *
6061  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6062  */
6063  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6064     uint8_t direct_address_typ, bd_addr_t direct_address,
6065     uint8_t channel_map, uint8_t filter_policy) {
6066 
6067     hci_stack->le_advertisements_interval_min = adv_int_min;
6068     hci_stack->le_advertisements_interval_max = adv_int_max;
6069     hci_stack->le_advertisements_type = adv_type;
6070     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6071     hci_stack->le_advertisements_channel_map = channel_map;
6072     hci_stack->le_advertisements_filter_policy = filter_policy;
6073     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6074                  6);
6075 
6076     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6077     hci_run();
6078  }
6079 
6080 /**
6081  * @brief Enable/Disable Advertisements
6082  * @param enabled
6083  */
6084 void gap_advertisements_enable(int enabled){
6085     hci_stack->le_advertisements_enabled = enabled != 0;
6086     hci_update_advertisements_enabled_for_current_roles();
6087     hci_run();
6088 }
6089 
6090 #endif
6091 
6092 void hci_le_set_own_address_type(uint8_t own_address_type){
6093     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6094     if (own_address_type == hci_stack->le_own_addr_type) return;
6095     hci_stack->le_own_addr_type = own_address_type;
6096 
6097 #ifdef ENABLE_LE_PERIPHERAL
6098     // update advertisement parameters, too
6099     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6100     hci_run();
6101 #endif
6102 #ifdef ENABLE_LE_CENTRAL
6103     // note: we don't update scan parameters or modify ongoing connection attempts
6104 #endif
6105 }
6106 
6107 void hci_le_random_address_set(const bd_addr_t random_address){
6108     memcpy(hci_stack->le_random_address, random_address, 6);
6109     hci_stack->le_random_address_set = true;
6110     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6111     hci_run();
6112 }
6113 
6114 #endif
6115 
6116 uint8_t gap_disconnect(hci_con_handle_t handle){
6117     hci_connection_t * conn = hci_connection_for_handle(handle);
6118     if (!conn){
6119         hci_emit_disconnection_complete(handle, 0);
6120         return 0;
6121     }
6122     // ignore if already disconnected
6123     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6124         return 0;
6125     }
6126     conn->state = SEND_DISCONNECT;
6127     hci_run();
6128     return 0;
6129 }
6130 
6131 int gap_read_rssi(hci_con_handle_t con_handle){
6132     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6133     if (hci_connection == NULL) return 0;
6134     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6135     hci_run();
6136     return 1;
6137 }
6138 
6139 /**
6140  * @brief Get connection type
6141  * @param con_handle
6142  * @result connection_type
6143  */
6144 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6145     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6146     if (!conn) return GAP_CONNECTION_INVALID;
6147     switch (conn->address_type){
6148         case BD_ADDR_TYPE_LE_PUBLIC:
6149         case BD_ADDR_TYPE_LE_RANDOM:
6150             return GAP_CONNECTION_LE;
6151         case BD_ADDR_TYPE_SCO:
6152             return GAP_CONNECTION_SCO;
6153         case BD_ADDR_TYPE_ACL:
6154             return GAP_CONNECTION_ACL;
6155         default:
6156             return GAP_CONNECTION_INVALID;
6157     }
6158 }
6159 
6160 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6161     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6162     if (!conn) return HCI_ROLE_INVALID;
6163     return (hci_role_t) conn->role;
6164 }
6165 
6166 
6167 #ifdef ENABLE_CLASSIC
6168 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6169     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6170     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6171     conn->request_role = role;
6172     hci_run();
6173     return ERROR_CODE_SUCCESS;
6174 }
6175 #endif
6176 
6177 #ifdef ENABLE_BLE
6178 
6179 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){
6180     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6181     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6182 
6183     conn->le_phy_update_all_phys    = all_phys;
6184     conn->le_phy_update_tx_phys     = tx_phys;
6185     conn->le_phy_update_rx_phys     = rx_phys;
6186     conn->le_phy_update_phy_options = phy_options;
6187 
6188     hci_run();
6189 
6190     return 0;
6191 }
6192 
6193 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6194     // check if already in list
6195     btstack_linked_list_iterator_t it;
6196     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6197     while (btstack_linked_list_iterator_has_next(&it)) {
6198         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6199         if (entry->address_type != address_type) {
6200             continue;
6201         }
6202         if (memcmp(entry->address, address, 6) != 0) {
6203             continue;
6204         }
6205 		// disallow if already scheduled to add
6206 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6207 			return ERROR_CODE_COMMAND_DISALLOWED;
6208 		}
6209 		// still on controller, but scheduled to remove -> re-add
6210 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6211 		return ERROR_CODE_SUCCESS;
6212     }
6213     // alloc and add to list
6214     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6215     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6216     entry->address_type = address_type;
6217     (void)memcpy(entry->address, address, 6);
6218     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6219     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6220     return ERROR_CODE_SUCCESS;
6221 }
6222 
6223 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6224     btstack_linked_list_iterator_t it;
6225     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6226     while (btstack_linked_list_iterator_has_next(&it)){
6227         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6228         if (entry->address_type != address_type) {
6229             continue;
6230         }
6231         if (memcmp(entry->address, address, 6) != 0) {
6232             continue;
6233         }
6234         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6235             // remove from controller if already present
6236             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6237         }  else {
6238             // directly remove entry from whitelist
6239             btstack_linked_list_iterator_remove(&it);
6240             btstack_memory_whitelist_entry_free(entry);
6241         }
6242         return ERROR_CODE_SUCCESS;
6243     }
6244     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6245 }
6246 
6247 static void hci_whitelist_clear(void){
6248     btstack_linked_list_iterator_t it;
6249     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6250     while (btstack_linked_list_iterator_has_next(&it)){
6251         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6252         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6253             // remove from controller if already present
6254             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6255             continue;
6256         }
6257         // directly remove entry from whitelist
6258         btstack_linked_list_iterator_remove(&it);
6259         btstack_memory_whitelist_entry_free(entry);
6260     }
6261 }
6262 
6263 // free all entries unconditionally
6264 static void hci_whitelist_free(void){
6265     btstack_linked_list_iterator_t lit;
6266     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
6267     while (btstack_linked_list_iterator_has_next(&lit)){
6268         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
6269         btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
6270         btstack_memory_whitelist_entry_free(entry);
6271     }
6272 }
6273 
6274 /**
6275  * @brief Clear Whitelist
6276  * @return 0 if ok
6277  */
6278 uint8_t gap_whitelist_clear(void){
6279     hci_whitelist_clear();
6280     hci_run();
6281     return ERROR_CODE_SUCCESS;
6282 }
6283 
6284 /**
6285  * @brief Add Device to Whitelist
6286  * @param address_typ
6287  * @param address
6288  * @return 0 if ok
6289  */
6290 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6291     uint8_t status = hci_whitelist_add(address_type, address);
6292     if (status){
6293         return status;
6294     }
6295     hci_run();
6296     return ERROR_CODE_SUCCESS;
6297 }
6298 
6299 /**
6300  * @brief Remove Device from Whitelist
6301  * @param address_typ
6302  * @param address
6303  * @return 0 if ok
6304  */
6305 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6306     uint8_t status = hci_whitelist_remove(address_type, address);
6307     if (status){
6308         return status;
6309     }
6310     hci_run();
6311     return ERROR_CODE_SUCCESS;
6312 }
6313 
6314 #ifdef ENABLE_LE_CENTRAL
6315 /**
6316  * @brief Connect with Whitelist
6317  * @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6318  * @return - if ok
6319  */
6320 uint8_t gap_connect_with_whitelist(void){
6321     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6322         return ERROR_CODE_COMMAND_DISALLOWED;
6323     }
6324     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6325     hci_run();
6326     return ERROR_CODE_SUCCESS;
6327 }
6328 
6329 /**
6330  * @brief Auto Connection Establishment - Start Connecting to device
6331  * @param address_typ
6332  * @param address
6333  * @return 0 if ok
6334  */
6335 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6336     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6337         return ERROR_CODE_COMMAND_DISALLOWED;
6338     }
6339 
6340     uint8_t status = hci_whitelist_add(address_type, address);
6341     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6342         return status;
6343     }
6344 
6345     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6346 
6347     hci_run();
6348     return ERROR_CODE_SUCCESS;
6349 }
6350 
6351 /**
6352  * @brief Auto Connection Establishment - Stop Connecting to device
6353  * @param address_typ
6354  * @param address
6355  * @return 0 if ok
6356  */
6357 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6358     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6359         return ERROR_CODE_COMMAND_DISALLOWED;
6360     }
6361 
6362     hci_whitelist_remove(address_type, address);
6363     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6364         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6365     }
6366     hci_run();
6367     return 0;
6368 }
6369 
6370 /**
6371  * @brief Auto Connection Establishment - Stop everything
6372  * @note  Convenience function to stop all active auto connection attempts
6373  */
6374 uint8_t gap_auto_connection_stop_all(void){
6375     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6376         return ERROR_CODE_COMMAND_DISALLOWED;
6377     }
6378     hci_whitelist_clear();
6379     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6380     hci_run();
6381     return ERROR_CODE_SUCCESS;
6382 }
6383 
6384 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6385     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6386     if (!conn) return 0;
6387     return conn->le_connection_interval;
6388 }
6389 #endif
6390 #endif
6391 
6392 #ifdef ENABLE_CLASSIC
6393 /**
6394  * @brief Set Extended Inquiry Response data
6395  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6396  * @note has to be done before stack starts up
6397  */
6398 void gap_set_extended_inquiry_response(const uint8_t * data){
6399     hci_stack->eir_data = data;
6400     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6401     hci_run();
6402 }
6403 
6404 /**
6405  * @brief Start GAP Classic Inquiry
6406  * @param duration in 1.28s units
6407  * @return 0 if ok
6408  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6409  */
6410 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6411     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6412     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6413     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6414         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6415     }
6416     hci_stack->inquiry_state = duration_in_1280ms_units;
6417     hci_run();
6418     return 0;
6419 }
6420 
6421 /**
6422  * @brief Stop GAP Classic Inquiry
6423  * @return 0 if ok
6424  */
6425 int gap_inquiry_stop(void){
6426     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6427         // emit inquiry complete event, before it even started
6428         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6429         hci_emit_event(event, sizeof(event), 1);
6430         return 0;
6431     }
6432     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6433     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6434     hci_run();
6435     return 0;
6436 }
6437 
6438 void gap_inquiry_set_lap(uint32_t lap){
6439     hci_stack->inquiry_lap = lap;
6440 }
6441 
6442 void gap_inquiry_set_scan_activity(uint16_t inquiry_scan_interval, uint16_t inquiry_scan_window){
6443     hci_stack->inquiry_scan_interval = inquiry_scan_interval;
6444     hci_stack->inquiry_scan_window   = inquiry_scan_window;
6445     hci_stack->gap_tasks |= GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
6446     hci_run();
6447 }
6448 
6449 
6450 /**
6451  * @brief Remote Name Request
6452  * @param addr
6453  * @param page_scan_repetition_mode
6454  * @param clock_offset only used when bit 15 is set
6455  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6456  */
6457 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6458     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6459     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6460     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6461     hci_stack->remote_name_clock_offset = clock_offset;
6462     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6463     hci_run();
6464     return 0;
6465 }
6466 
6467 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6468     hci_stack->gap_pairing_state = state;
6469     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6470     hci_run();
6471     return 0;
6472 }
6473 
6474 /**
6475  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6476  * @param addr
6477  * @param pin_data
6478  * @param pin_len
6479  * @return 0 if ok
6480  */
6481 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6482     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6483     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6484     hci_stack->gap_pairing_pin_len = pin_len;
6485     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6486 }
6487 
6488 /**
6489  * @brief Legacy Pairing Pin Code Response
6490  * @param addr
6491  * @param pin
6492  * @return 0 if ok
6493  */
6494 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6495     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6496 }
6497 
6498 /**
6499  * @brief Abort Legacy Pairing
6500  * @param addr
6501  * @param pin
6502  * @return 0 if ok
6503  */
6504 int gap_pin_code_negative(bd_addr_t addr){
6505     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6506     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6507 }
6508 
6509 /**
6510  * @brief SSP Passkey Response
6511  * @param addr
6512  * @param passkey
6513  * @return 0 if ok
6514  */
6515 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6516     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6517     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6518     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6519 }
6520 
6521 /**
6522  * @brief Abort SSP Passkey Entry/Pairing
6523  * @param addr
6524  * @param pin
6525  * @return 0 if ok
6526  */
6527 int gap_ssp_passkey_negative(const bd_addr_t addr){
6528     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6529     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6530 }
6531 
6532 /**
6533  * @brief Accept SSP Numeric Comparison
6534  * @param addr
6535  * @param passkey
6536  * @return 0 if ok
6537  */
6538 int gap_ssp_confirmation_response(const bd_addr_t addr){
6539     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6540     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6541 }
6542 
6543 /**
6544  * @brief Abort SSP Numeric Comparison/Pairing
6545  * @param addr
6546  * @param pin
6547  * @return 0 if ok
6548  */
6549 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6550     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6551     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6552 }
6553 
6554 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6555 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6556     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6557     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6558     connectionSetAuthenticationFlags(conn, flag);
6559     hci_run();
6560     return ERROR_CODE_SUCCESS;
6561 }
6562 #endif
6563 
6564 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6565 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6566     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6567 }
6568 
6569 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6570     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6571 }
6572 #endif
6573 
6574 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6575 /**
6576  * @brief Report Remote OOB Data
6577  * @param bd_addr
6578  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6579  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6580  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6581  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6582  */
6583 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){
6584     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6585     if (connection == NULL) {
6586         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6587     }
6588     connection->classic_oob_c_192 = c_192;
6589     connection->classic_oob_r_192 = r_192;
6590 
6591     // ignore P-256 if not supported by us
6592     if (hci_stack->secure_connections_active){
6593         connection->classic_oob_c_256 = c_256;
6594         connection->classic_oob_r_256 = r_256;
6595     }
6596 
6597     return ERROR_CODE_SUCCESS;
6598 }
6599 /**
6600  * @brief Generate new OOB data
6601  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6602  */
6603 void gap_ssp_generate_oob_data(void){
6604     hci_stack->classic_read_local_oob_data = true;
6605     hci_run();
6606 }
6607 
6608 #endif
6609 
6610 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6611 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6612     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6613     if (connection == NULL) {
6614         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6615     }
6616 
6617     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6618     connection->link_key_type = type;
6619 
6620     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6621 }
6622 
6623 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6624 /**
6625  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6626  * @param inquiry_mode see bluetooth_defines.h
6627  */
6628 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6629     hci_stack->inquiry_mode = inquiry_mode;
6630 }
6631 
6632 /**
6633  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6634  */
6635 void hci_set_sco_voice_setting(uint16_t voice_setting){
6636     hci_stack->sco_voice_setting = voice_setting;
6637 }
6638 
6639 /**
6640  * @brief Get SCO Voice Setting
6641  * @return current voice setting
6642  */
6643 uint16_t hci_get_sco_voice_setting(void){
6644     return hci_stack->sco_voice_setting;
6645 }
6646 
6647 static int hci_have_usb_transport(void){
6648     if (!hci_stack->hci_transport) return 0;
6649     const char * transport_name = hci_stack->hci_transport->name;
6650     if (!transport_name) return 0;
6651     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6652 }
6653 
6654 /** @brief Get SCO packet length for current SCO Voice setting
6655  *  @note  Using SCO packets of the exact length is required for USB transfer
6656  *  @return Length of SCO packets in bytes (not audio frames)
6657  */
6658 uint16_t hci_get_sco_packet_length(void){
6659     uint16_t sco_packet_length = 0;
6660 
6661 #ifdef ENABLE_SCO_OVER_HCI
6662     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6663     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6664 
6665     if (hci_have_usb_transport()){
6666         // see Core Spec for H2 USB Transfer.
6667         // 3 byte SCO header + 24 bytes per connection
6668         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6669         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6670     } else {
6671         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6672         sco_packet_length = 3 + 60 * multiplier;
6673         // assert that it still fits inside an SCO buffer
6674         if (sco_packet_length > hci_stack->sco_data_packet_length){
6675             sco_packet_length = 3 + 60;
6676         }
6677     }
6678 #endif
6679 
6680 #ifdef HAVE_SCO_TRANSPORT
6681     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6682     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6683     sco_packet_length = 3 + 60 * multiplier;
6684 #endif
6685     return sco_packet_length;
6686 }
6687 
6688 /**
6689 * @brief Sets the master/slave policy
6690 * @param policy (0: attempt to become master, 1: let connecting device decide)
6691 */
6692 void hci_set_master_slave_policy(uint8_t policy){
6693     hci_stack->master_slave_policy = policy;
6694 }
6695 
6696 #endif
6697 
6698 HCI_STATE hci_get_state(void){
6699     return hci_stack->state;
6700 }
6701 
6702 #ifdef ENABLE_CLASSIC
6703 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6704     hci_stack->gap_classic_accept_callback = accept_callback;
6705 }
6706 #endif
6707 
6708 /**
6709  * @brief Set callback for Bluetooth Hardware Error
6710  */
6711 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6712     hci_stack->hardware_error_callback = fn;
6713 }
6714 
6715 void hci_disconnect_all(void){
6716     btstack_linked_list_iterator_t it;
6717     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6718     while (btstack_linked_list_iterator_has_next(&it)){
6719         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6720         if (con->state == SENT_DISCONNECT) continue;
6721         con->state = SEND_DISCONNECT;
6722     }
6723     hci_run();
6724 }
6725 
6726 uint16_t hci_get_manufacturer(void){
6727     return hci_stack->manufacturer;
6728 }
6729 
6730 #ifdef ENABLE_BLE
6731 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6732     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6733     if (!hci_con) return NULL;
6734     return &hci_con->sm_connection;
6735 }
6736 
6737 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6738 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6739 #endif
6740 
6741 int gap_encryption_key_size(hci_con_handle_t con_handle){
6742     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6743     if (hci_connection == NULL) return 0;
6744     if (hci_is_le_connection(hci_connection)){
6745 #ifdef ENABLE_BLE
6746         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6747         if (sm_conn->sm_connection_encrypted) {
6748             return sm_conn->sm_actual_encryption_key_size;
6749         }
6750 #endif
6751     } else {
6752 #ifdef ENABLE_CLASSIC
6753         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6754             return hci_connection->encryption_key_size;
6755         }
6756 #endif
6757     }
6758     return 0;
6759 }
6760 
6761 int gap_authenticated(hci_con_handle_t con_handle){
6762     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6763     if (hci_connection == NULL) return 0;
6764 
6765     switch (hci_connection->address_type){
6766 #ifdef ENABLE_BLE
6767         case BD_ADDR_TYPE_LE_PUBLIC:
6768         case BD_ADDR_TYPE_LE_RANDOM:
6769             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6770             return hci_connection->sm_connection.sm_connection_authenticated;
6771 #endif
6772 #ifdef ENABLE_CLASSIC
6773         case BD_ADDR_TYPE_SCO:
6774         case BD_ADDR_TYPE_ACL:
6775             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6776 #endif
6777         default:
6778             return 0;
6779     }
6780 }
6781 
6782 int gap_secure_connection(hci_con_handle_t con_handle){
6783     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6784     if (hci_connection == NULL) return 0;
6785 
6786     switch (hci_connection->address_type){
6787 #ifdef ENABLE_BLE
6788         case BD_ADDR_TYPE_LE_PUBLIC:
6789         case BD_ADDR_TYPE_LE_RANDOM:
6790             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6791             return hci_connection->sm_connection.sm_connection_sc;
6792 #endif
6793 #ifdef ENABLE_CLASSIC
6794         case BD_ADDR_TYPE_SCO:
6795         case BD_ADDR_TYPE_ACL:
6796             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6797 #endif
6798         default:
6799             return 0;
6800     }
6801 }
6802 
6803 bool gap_bonded(hci_con_handle_t con_handle){
6804 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6805 	if (hci_connection == NULL) return 0;
6806 
6807 #ifdef ENABLE_CLASSIC
6808 	link_key_t link_key;
6809 	link_key_type_t link_key_type;
6810 #endif
6811 	switch (hci_connection->address_type){
6812 #ifdef ENABLE_BLE
6813 		case BD_ADDR_TYPE_LE_PUBLIC:
6814 		case BD_ADDR_TYPE_LE_RANDOM:
6815 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6816 #endif
6817 #ifdef ENABLE_CLASSIC
6818 		case BD_ADDR_TYPE_SCO:
6819 		case BD_ADDR_TYPE_ACL:
6820 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6821 #endif
6822 		default:
6823 			return false;
6824 	}
6825 }
6826 
6827 #ifdef ENABLE_BLE
6828 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6829     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6830     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6831     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6832     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6833     return sm_conn->sm_connection_authorization_state;
6834 }
6835 #endif
6836 
6837 #ifdef ENABLE_CLASSIC
6838 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){
6839     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6840     if (!conn) return GAP_CONNECTION_INVALID;
6841     conn->sniff_min_interval = sniff_min_interval;
6842     conn->sniff_max_interval = sniff_max_interval;
6843     conn->sniff_attempt = sniff_attempt;
6844     conn->sniff_timeout = sniff_timeout;
6845     hci_run();
6846     return 0;
6847 }
6848 
6849 /**
6850  * @brief Exit Sniff mode
6851  * @param con_handle
6852  @ @return 0 if ok
6853  */
6854 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6855     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6856     if (!conn) return GAP_CONNECTION_INVALID;
6857     conn->sniff_min_interval = 0xffff;
6858     hci_run();
6859     return 0;
6860 }
6861 
6862 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){
6863     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6864     if (!conn) return GAP_CONNECTION_INVALID;
6865     conn->sniff_subrating_max_latency = max_latency;
6866     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6867     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6868     hci_run();
6869     return ERROR_CODE_SUCCESS;
6870 }
6871 
6872 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){
6873     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6874     if (!conn) return GAP_CONNECTION_INVALID;
6875     conn->qos_service_type = service_type;
6876     conn->qos_token_rate = token_rate;
6877     conn->qos_peak_bandwidth = peak_bandwidth;
6878     conn->qos_latency = latency;
6879     conn->qos_delay_variation = delay_variation;
6880     hci_run();
6881     return ERROR_CODE_SUCCESS;
6882 }
6883 
6884 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6885     hci_stack->new_page_scan_interval = page_scan_interval;
6886     hci_stack->new_page_scan_window = page_scan_window;
6887     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6888     hci_run();
6889 }
6890 
6891 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6892     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6893     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6894     hci_run();
6895 }
6896 
6897 void gap_set_page_timeout(uint16_t page_timeout){
6898     hci_stack->page_timeout = page_timeout;
6899     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_TIMEOUT;
6900     hci_run();
6901 }
6902 
6903 #endif
6904 
6905 void hci_halting_defer(void){
6906     if (hci_stack->state != HCI_STATE_HALTING) return;
6907     switch (hci_stack->substate){
6908         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6909         case HCI_HALTING_CLOSE:
6910             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6911             break;
6912         default:
6913             break;
6914     }
6915 }
6916 
6917 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6918 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6919     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6920     if (le_device_db_index >= le_device_db_max_count()) return;
6921     uint8_t offset = le_device_db_index >> 3;
6922     uint8_t mask = 1 << (le_device_db_index & 7);
6923     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6924     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6925     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6926         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6927     }
6928 }
6929 
6930 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6931 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6932 	if (le_device_db_index >= le_device_db_max_count()) return;
6933 	uint8_t offset = le_device_db_index >> 3;
6934 	uint8_t mask = 1 << (le_device_db_index & 7);
6935 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6936 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6937 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6938 	}
6939 }
6940 
6941 uint8_t gap_load_resolving_list_from_le_device_db(void){
6942 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6943 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6944 	}
6945 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6946 		// restart le resolving list update
6947 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6948 	}
6949 	return ERROR_CODE_SUCCESS;
6950 }
6951 #endif
6952 
6953 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6954 void hci_setup_test_connections_fuzz(void){
6955     hci_connection_t * conn;
6956 
6957     // default address: 66:55:44:33:00:01
6958     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6959 
6960     // setup Controller info
6961     hci_stack->num_cmd_packets = 255;
6962     hci_stack->acl_packets_total_num = 255;
6963 
6964     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6965     addr[5] = 0x01;
6966     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6967     conn->con_handle = addr[5];
6968     conn->role  = HCI_ROLE_SLAVE;
6969     conn->state = RECEIVED_CONNECTION_REQUEST;
6970     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6971 
6972     // setup incoming Classic SCO connection with con handle 0x0002
6973     addr[5] = 0x02;
6974     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6975     conn->con_handle = addr[5];
6976     conn->role  = HCI_ROLE_SLAVE;
6977     conn->state = RECEIVED_CONNECTION_REQUEST;
6978     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6979 
6980     // setup ready Classic ACL connection with con handle 0x0003
6981     addr[5] = 0x03;
6982     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6983     conn->con_handle = addr[5];
6984     conn->role  = HCI_ROLE_SLAVE;
6985     conn->state = OPEN;
6986     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6987 
6988     // setup ready Classic SCO connection with con handle 0x0004
6989     addr[5] = 0x04;
6990     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6991     conn->con_handle = addr[5];
6992     conn->role  = HCI_ROLE_SLAVE;
6993     conn->state = OPEN;
6994     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6995 
6996     // setup ready LE ACL connection with con handle 0x005 and public address
6997     addr[5] = 0x05;
6998     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6999     conn->con_handle = addr[5];
7000     conn->role  = HCI_ROLE_SLAVE;
7001     conn->state = OPEN;
7002     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
7003     conn->sm_connection.sm_connection_encrypted = 1;
7004 }
7005 
7006 void hci_free_connections_fuzz(void){
7007     btstack_linked_list_iterator_t it;
7008     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
7009     while (btstack_linked_list_iterator_has_next(&it)){
7010         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
7011         btstack_linked_list_iterator_remove(&it);
7012         btstack_memory_hci_connection_free(con);
7013     }
7014 }
7015 void hci_simulate_working_fuzz(void){
7016     hci_init_done();
7017     hci_stack->num_cmd_packets = 255;
7018 }
7019 #endif
7020