xref: /btstack/src/hci.c (revision 1f9eb2cc913999a69999dc226939d713e116cfd3)
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_emit_transport_packet_sent(void);
156 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
157 static void hci_emit_nr_connections_changed(void);
158 static void hci_emit_hci_open_failed(void);
159 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
160 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
161 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
162 static void hci_run(void);
163 static int  hci_is_le_connection(hci_connection_t * connection);
164 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
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 static int 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 free_slots_classic;
591 
592         default:
593            if (hci_stack->le_acl_packets_total_num){
594                return free_slots_le;
595            }
596            return 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 static int gap_ssp_supported(void){
1146     // No. 51, byte 6, bit 3
1147     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1148 }
1149 
1150 static int hci_classic_supported(void){
1151 #ifdef ENABLE_CLASSIC
1152     // No. 37, byte 4, bit 5, = No BR/EDR Support
1153     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1154 #else
1155     return 0;
1156 #endif
1157 }
1158 
1159 static int hci_le_supported(void){
1160 #ifdef ENABLE_BLE
1161     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1162     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1163 #else
1164     return 0;
1165 #endif
1166 }
1167 
1168 #ifdef ENABLE_BLE
1169 
1170 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1171     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1172         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1173     } else {
1174         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1175     }
1176 }
1177 
1178 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1179     *addr_type = hci_stack->le_own_addr_type;
1180     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1181 }
1182 
1183 #ifdef ENABLE_LE_PERIPHERAL
1184 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1185     *addr_type = hci_stack->le_advertisements_own_addr_type;
1186     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1187 };
1188 #endif
1189 
1190 #ifdef ENABLE_LE_CENTRAL
1191 
1192 /**
1193  * @brief Get own addr type and address used for LE connections (Central)
1194  */
1195 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1196     *addr_type = hci_stack->le_connection_own_addr_type;
1197     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1198 }
1199 
1200 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1201 
1202     int offset = 3;
1203     int num_reports = packet[offset];
1204     offset += 1;
1205 
1206     int i;
1207     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1208     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1209     for (i=0; (i<num_reports) && (offset < size);i++){
1210         // sanity checks on data_length:
1211         uint8_t data_length = packet[offset + 8];
1212         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1213         if ((offset + 9u + data_length + 1u) > size)    return;
1214         // setup event
1215         uint8_t event_size = 10u + data_length;
1216         int pos = 0;
1217         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1218         event[pos++] = event_size;
1219         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1220         offset += 8;
1221         pos += 8;
1222         event[pos++] = packet[offset + 1 + data_length]; // rssi
1223         event[pos++] = data_length;
1224         offset++;
1225         (void)memcpy(&event[pos], &packet[offset], data_length);
1226         pos +=    data_length;
1227         offset += data_length + 1u; // rssi
1228         hci_emit_event(event, pos, 1);
1229     }
1230 }
1231 #endif
1232 #endif
1233 
1234 #ifdef ENABLE_BLE
1235 #ifdef ENABLE_LE_PERIPHERAL
1236 static void hci_update_advertisements_enabled_for_current_roles(void){
1237     if (hci_stack->le_advertisements_enabled){
1238         // get number of active le slave connections
1239         int num_slave_connections = 0;
1240         btstack_linked_list_iterator_t it;
1241         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1242         while (btstack_linked_list_iterator_has_next(&it)){
1243             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1244             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1245             if (con->state != OPEN) continue;
1246             if (con->role  != HCI_ROLE_SLAVE) continue;
1247             if (!hci_is_le_connection(con)) continue;
1248             num_slave_connections++;
1249         }
1250         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1251         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1252     } else {
1253         hci_stack->le_advertisements_enabled_for_current_roles = false;
1254     }
1255 }
1256 #endif
1257 #endif
1258 
1259 #ifdef ENABLE_CLASSIC
1260 static void gap_run_set_local_name(void){
1261     hci_reserve_packet_buffer();
1262     uint8_t * packet = hci_stack->hci_packet_buffer;
1263     // construct HCI Command and send
1264     uint16_t opcode = hci_write_local_name.opcode;
1265     hci_stack->last_cmd_opcode = opcode;
1266     packet[0] = opcode & 0xff;
1267     packet[1] = opcode >> 8;
1268     packet[2] = DEVICE_NAME_LEN;
1269     memset(&packet[3], 0, DEVICE_NAME_LEN);
1270     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1271     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1272     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1273     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1274     // expand '00:00:00:00:00:00' in name with bd_addr
1275     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1276     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1277 }
1278 
1279 static void gap_run_set_eir_data(void){
1280     hci_reserve_packet_buffer();
1281     uint8_t * packet = hci_stack->hci_packet_buffer;
1282     // construct HCI Command in-place and send
1283     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1284     hci_stack->last_cmd_opcode = opcode;
1285     uint16_t offset = 0;
1286     packet[offset++] = opcode & 0xff;
1287     packet[offset++] = opcode >> 8;
1288     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1289     packet[offset++] = 0;  // FEC not required
1290     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1291     if (hci_stack->eir_data){
1292         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1293         ad_context_t context;
1294         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1295             uint8_t data_type   = ad_iterator_get_data_type(&context);
1296             uint8_t size        = ad_iterator_get_data_len(&context);
1297             const uint8_t *data = ad_iterator_get_data(&context);
1298             // copy item
1299             packet[offset++] = size + 1;
1300             packet[offset++] = data_type;
1301             memcpy(&packet[offset], data, size);
1302             // update name item
1303             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1304                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1305             }
1306             offset += size;
1307         }
1308     } else {
1309         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1310         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1311         packet[offset++] = bytes_to_copy + 1;
1312         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1313         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1314         // expand '00:00:00:00:00:00' in name with bd_addr
1315         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1316     }
1317     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1318 }
1319 
1320 static void hci_run_gap_tasks_classic(void){
1321     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1322         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1323         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1324         return;
1325     }
1326     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1327         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1328         gap_run_set_local_name();
1329         return;
1330     }
1331     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1332         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1333         gap_run_set_eir_data();
1334         return;
1335     }
1336     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1337         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1338         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1339         return;
1340     }
1341     // write page scan activity
1342     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1343         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1344         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1345         return;
1346     }
1347     // write page scan type
1348     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1349         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1350         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1351         return;
1352     }
1353     // write page timeout
1354     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_TIMEOUT) != 0) {
1355         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_TIMEOUT;
1356         hci_send_cmd(&hci_write_page_timeout, hci_stack->page_timeout);
1357         return;
1358     }
1359     // send scan enable
1360     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1361         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1362         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1363         return;
1364     }
1365     // send write scan activity
1366     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY) != 0) {
1367         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
1368         hci_send_cmd(&hci_write_inquiry_scan_activity, hci_stack->inquiry_scan_interval, hci_stack->inquiry_scan_window);
1369         return;
1370     }
1371 }
1372 #endif
1373 
1374 #ifndef HAVE_HOST_CONTROLLER_API
1375 
1376 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1377     if (!hci_stack->config) return 0;
1378     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1379     // Limit baud rate for Broadcom chipsets to 3 mbps
1380     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1381         baud_rate = 3000000;
1382     }
1383     return baud_rate;
1384 }
1385 
1386 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1387     UNUSED(ds);
1388 
1389     switch (hci_stack->substate){
1390         case HCI_INIT_W4_SEND_RESET:
1391             log_info("Resend HCI Reset");
1392             hci_stack->substate = HCI_INIT_SEND_RESET;
1393             hci_stack->num_cmd_packets = 1;
1394             hci_run();
1395             break;
1396         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1397             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1398             if (hci_stack->hci_transport->reset_link){
1399                 hci_stack->hci_transport->reset_link();
1400             }
1401 
1402             /* fall through */
1403 
1404         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1405             log_info("Resend HCI Reset - CSR Warm Boot");
1406             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1407             hci_stack->num_cmd_packets = 1;
1408             hci_run();
1409             break;
1410         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1411             if (hci_stack->hci_transport->set_baudrate){
1412                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1413                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1414                 hci_stack->hci_transport->set_baudrate(baud_rate);
1415             }
1416             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1417             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1418                 if (hci_stack->hci_transport->reset_link){
1419                     log_info("Link Reset");
1420                     hci_stack->hci_transport->reset_link();
1421                 }
1422                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1423                 hci_run();
1424             }
1425             break;
1426         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1427             // otherwise continue
1428             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1429             hci_send_cmd(&hci_read_local_supported_commands);
1430             break;
1431         default:
1432             break;
1433     }
1434 }
1435 #endif
1436 
1437 static void hci_initializing_next_state(void){
1438     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1439 }
1440 
1441 static void hci_init_done(void){
1442     // done. tell the app
1443     log_info("hci_init_done -> HCI_STATE_WORKING");
1444     hci_stack->state = HCI_STATE_WORKING;
1445     hci_emit_state();
1446 }
1447 
1448 // assumption: hci_can_send_command_packet_now() == true
1449 static void hci_initializing_run(void){
1450     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1451 
1452 #ifndef HAVE_HOST_CONTROLLER_API
1453     bool need_baud_change = hci_stack->config
1454             && hci_stack->chipset
1455             && hci_stack->chipset->set_baudrate_command
1456             && hci_stack->hci_transport->set_baudrate
1457             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1458 #endif
1459 
1460     switch (hci_stack->substate){
1461         case HCI_INIT_SEND_RESET:
1462             hci_state_reset();
1463 
1464 #ifndef HAVE_HOST_CONTROLLER_API
1465             // prepare reset if command complete not received in 100ms
1466             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1467             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1468             btstack_run_loop_add_timer(&hci_stack->timeout);
1469 #endif
1470             // send command
1471             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1472             hci_send_cmd(&hci_reset);
1473             break;
1474         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1475             hci_send_cmd(&hci_read_local_version_information);
1476             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1477             break;
1478 
1479 #ifndef HAVE_HOST_CONTROLLER_API
1480         case HCI_INIT_SEND_READ_LOCAL_NAME:
1481             hci_send_cmd(&hci_read_local_name);
1482             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1483             break;
1484         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1485             hci_state_reset();
1486             // prepare reset if command complete not received in 100ms
1487             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1488             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1489             btstack_run_loop_add_timer(&hci_stack->timeout);
1490             // send command
1491             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1492             hci_send_cmd(&hci_reset);
1493             break;
1494         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1495             hci_state_reset();
1496             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1497             hci_send_cmd(&hci_reset);
1498             break;
1499         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1500             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1501             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1502             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1503             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1504             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1505             break;
1506         }
1507         case HCI_INIT_SET_BD_ADDR:
1508             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1509             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1510             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1511             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1512             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1513             break;
1514         case HCI_INIT_SEND_BAUD_CHANGE:
1515             if (need_baud_change) {
1516                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1517                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1518                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1519                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1520                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1521                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1522                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1523                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1524                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1525                     btstack_run_loop_add_timer(&hci_stack->timeout);
1526                }
1527                break;
1528             }
1529 
1530             /* fall through */
1531 
1532         case HCI_INIT_CUSTOM_INIT:
1533             // Custom initialization
1534             if (hci_stack->chipset && hci_stack->chipset->next_command){
1535                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1536                 bool send_cmd = false;
1537                 switch (hci_stack->chipset_result){
1538                     case BTSTACK_CHIPSET_VALID_COMMAND:
1539                         send_cmd = true;
1540                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1541                         break;
1542                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1543                         send_cmd = true;
1544                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1545                         log_info("CSR Warm Boot");
1546                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1547                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1548                         btstack_run_loop_add_timer(&hci_stack->timeout);
1549                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1550                             && hci_stack->config
1551                             && hci_stack->chipset
1552                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1553                             && hci_stack->hci_transport->set_baudrate
1554                             && hci_transport_uart_get_main_baud_rate()){
1555                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1556                         } else {
1557                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1558                         }
1559                         break;
1560                     default:
1561                         break;
1562                 }
1563 
1564                 if (send_cmd){
1565                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1566                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1567                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1568                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1569                     break;
1570                 }
1571                 log_info("Init script done");
1572 
1573                 // Init script download on Broadcom chipsets causes:
1574                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1575                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1576                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1577 
1578                     // - baud rate to reset, restore UART baud rate if needed
1579                     if (need_baud_change) {
1580                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1581                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1582                         hci_stack->hci_transport->set_baudrate(baud_rate);
1583                     }
1584 
1585                     uint16_t bcm_delay_ms = 300;
1586                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1587                     //   -> Work around: wait here.
1588                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1589                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1590                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1591                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1592                     btstack_run_loop_add_timer(&hci_stack->timeout);
1593                     break;
1594                 }
1595             }
1596 #endif
1597             /* fall through */
1598 
1599         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1600             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1601             hci_send_cmd(&hci_read_local_supported_commands);
1602             break;
1603         case HCI_INIT_READ_BD_ADDR:
1604             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1605             hci_send_cmd(&hci_read_bd_addr);
1606             break;
1607         case HCI_INIT_READ_BUFFER_SIZE:
1608             // only read buffer size if supported
1609             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1610                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1611                 hci_send_cmd(&hci_read_buffer_size);
1612                 break;
1613             }
1614 
1615             /* fall through */
1616 
1617         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1618             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1619             hci_send_cmd(&hci_read_local_supported_features);
1620             break;
1621 
1622 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1623         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1624             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1625             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1626             break;
1627         case HCI_INIT_HOST_BUFFER_SIZE:
1628             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1629             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1630                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1631             break;
1632 #endif
1633 
1634         case HCI_INIT_SET_EVENT_MASK:
1635             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1636             if (hci_le_supported()){
1637                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1638             } else {
1639                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1640                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1641             }
1642             break;
1643 
1644 #ifdef ENABLE_CLASSIC
1645         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1646             if (hci_classic_supported() && gap_ssp_supported()){
1647                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1648                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1649                 break;
1650             }
1651 
1652             /* fall through */
1653 
1654         case HCI_INIT_WRITE_INQUIRY_MODE:
1655             if (hci_classic_supported()){
1656                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1657                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1658                 break;
1659             }
1660 
1661             /* fall through */
1662 
1663         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1664             // skip write secure connections host support if not supported or disabled
1665             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1666                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1667                 hci_stack->secure_connections_active = true;
1668                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1669                 break;
1670             }
1671 
1672 #ifdef ENABLE_SCO_OVER_HCI
1673             /* fall through */
1674 
1675         // only sent if ENABLE_SCO_OVER_HCI is defined
1676         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1677             // skip write synchronous flow control if not supported
1678             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1679                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1680                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1681                 break;
1682             }
1683             /* fall through */
1684 
1685         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1686             // skip write default erroneous data reporting if not supported
1687             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1688                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1689                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1690                 break;
1691             }
1692 #endif
1693 
1694 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1695             /* fall through */
1696 
1697         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1698         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1699             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1700                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1701 #ifdef ENABLE_SCO_OVER_HCI
1702                 log_info("BCM: Route SCO data via HCI transport");
1703                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1704 #endif
1705 #ifdef ENABLE_SCO_OVER_PCM
1706                 log_info("BCM: Route SCO data via PCM interface");
1707 #ifdef ENABLE_BCM_PCM_WBS
1708                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1709                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1710 #else
1711                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1712                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1713 #endif
1714 #endif
1715                 break;
1716             }
1717 #endif
1718 
1719 #ifdef ENABLE_SCO_OVER_PCM
1720             /* fall through */
1721 
1722         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1723             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1724                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1725                 log_info("BCM: Config PCM interface for I2S");
1726 #ifdef ENABLE_BCM_PCM_WBS
1727                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1728                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1729 #else
1730                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1731                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1732 #endif
1733                 break;
1734             }
1735 #endif
1736 #endif
1737 
1738 #ifdef ENABLE_BLE
1739             /* fall through */
1740 
1741         // LE INIT
1742         case HCI_INIT_LE_READ_BUFFER_SIZE:
1743             if (hci_le_supported()){
1744                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1745                 hci_send_cmd(&hci_le_read_buffer_size);
1746                 break;
1747             }
1748 
1749             /* fall through */
1750 
1751         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1752             // skip write le host if not supported (e.g. on LE only EM9301)
1753             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1754                 // LE Supported Host = 1, Simultaneous Host = 0
1755                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1756                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1757                 break;
1758             }
1759 
1760             /* fall through */
1761 
1762         case HCI_INIT_LE_SET_EVENT_MASK:
1763             if (hci_le_supported()){
1764                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1765                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1766                 break;
1767             }
1768 #endif
1769 
1770 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1771             /* fall through */
1772 
1773         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1774             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1775                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1776                 hci_send_cmd(&hci_le_read_maximum_data_length);
1777                 break;
1778             }
1779 
1780             /* fall through */
1781 
1782         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1783             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1784                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1785                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1786                 break;
1787             }
1788 #endif
1789 
1790 #ifdef ENABLE_LE_CENTRAL
1791             /* fall through */
1792 
1793         case HCI_INIT_READ_WHITE_LIST_SIZE:
1794             if (hci_le_supported()){
1795                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1796                 hci_send_cmd(&hci_le_read_white_list_size);
1797                 break;
1798             }
1799 
1800             /* fall through */
1801 
1802         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1803             if (hci_le_supported()){
1804                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1805                 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);
1806                 break;
1807             }
1808 #endif
1809 
1810             /* fall through */
1811 
1812         case HCI_INIT_DONE:
1813             hci_stack->substate = HCI_INIT_DONE;
1814 #ifdef ENABLE_CLASSIC
1815             // init sequence complete, check if GAP Tasks are completed
1816             if (hci_stack->gap_tasks != 0) {
1817                 hci_run_gap_tasks_classic();
1818                 break;
1819             }
1820 #endif
1821             hci_init_done();
1822             break;
1823 
1824         default:
1825             return;
1826     }
1827 }
1828 
1829 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1830     bool command_completed = false;
1831     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1832         uint16_t opcode = little_endian_read_16(packet,3);
1833         if (opcode == hci_stack->last_cmd_opcode){
1834             command_completed = true;
1835             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1836         } else {
1837             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1838         }
1839     }
1840 
1841     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1842         uint8_t  status = packet[2];
1843         uint16_t opcode = little_endian_read_16(packet,4);
1844         if (opcode == hci_stack->last_cmd_opcode){
1845             if (status){
1846                 command_completed = true;
1847                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1848             } else {
1849                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1850             }
1851         } else {
1852             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1853         }
1854     }
1855 #ifndef HAVE_HOST_CONTROLLER_API
1856     // Vendor == CSR
1857     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1858         // TODO: track actual command
1859         command_completed = true;
1860     }
1861 
1862     // Vendor == Toshiba
1863     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1864         // TODO: track actual command
1865         command_completed = true;
1866         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1867         hci_stack->num_cmd_packets = 1;
1868     }
1869 #endif
1870 
1871     return command_completed;
1872 }
1873 
1874 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1875 
1876     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1877 
1878     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1879 
1880 #ifndef HAVE_HOST_CONTROLLER_API
1881 
1882     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1883     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1884     //
1885     // HCI Reset
1886     // Timeout 100 ms
1887     // HCI Reset
1888     // Command Complete Reset
1889     // HCI Read Local Version Information
1890     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1891     // hang...
1892     //
1893     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1894     if (!command_completed
1895             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1896             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1897 
1898         uint16_t opcode = little_endian_read_16(packet,3);
1899         if (opcode == hci_reset.opcode){
1900             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1901             return;
1902         }
1903     }
1904 
1905     // CSR & H5
1906     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1907     if (!command_completed
1908             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1909             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1910 
1911         uint16_t opcode = little_endian_read_16(packet,3);
1912         if (opcode == hci_reset.opcode){
1913             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1914             return;
1915         }
1916     }
1917 
1918     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1919     // fix: Correct substate and behave as command below
1920     if (command_completed){
1921         switch (hci_stack->substate){
1922             case HCI_INIT_SEND_RESET:
1923                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1924                 break;
1925             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1926                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1927                 break;
1928             default:
1929                 break;
1930         }
1931     }
1932 
1933 #endif
1934 
1935     if (!command_completed) return;
1936 
1937     bool need_baud_change = false;
1938     bool need_addr_change = false;
1939 
1940 #ifndef HAVE_HOST_CONTROLLER_API
1941     need_baud_change = hci_stack->config
1942                         && hci_stack->chipset
1943                         && hci_stack->chipset->set_baudrate_command
1944                         && hci_stack->hci_transport->set_baudrate
1945                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1946 
1947     need_addr_change = hci_stack->custom_bd_addr_set
1948                         && hci_stack->chipset
1949                         && hci_stack->chipset->set_bd_addr_command;
1950 #endif
1951 
1952     switch(hci_stack->substate){
1953 
1954 #ifndef HAVE_HOST_CONTROLLER_API
1955         case HCI_INIT_SEND_RESET:
1956             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1957             // fix: just correct substate and behave as command below
1958 
1959             /* fall through */
1960 #endif
1961 
1962         case HCI_INIT_W4_SEND_RESET:
1963             btstack_run_loop_remove_timer(&hci_stack->timeout);
1964             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1965             return;
1966 
1967 #ifndef HAVE_HOST_CONTROLLER_API
1968         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1969             // for STLC2500D, baud rate change already happened.
1970             // for others, baud rate gets changed now
1971             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1972                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1973                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1974                 hci_stack->hci_transport->set_baudrate(baud_rate);
1975             }
1976             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1977             return;
1978         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1979             btstack_run_loop_remove_timer(&hci_stack->timeout);
1980             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1981             return;
1982         case HCI_INIT_W4_CUSTOM_INIT:
1983             // repeat custom init
1984             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1985             return;
1986 #endif
1987 
1988         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1989             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1990               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1991                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1992                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1993                 return;
1994             }
1995             if (need_addr_change){
1996                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1997                 return;
1998             }
1999             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2000             return;
2001 #ifndef HAVE_HOST_CONTROLLER_API
2002         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
2003             if (need_baud_change){
2004                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
2005                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
2006                 hci_stack->hci_transport->set_baudrate(baud_rate);
2007             }
2008             if (need_addr_change){
2009                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2010                 return;
2011             }
2012             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2013             return;
2014         case HCI_INIT_W4_SET_BD_ADDR:
2015             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
2016             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
2017             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2018                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2019                 return;
2020             }
2021             // skipping st warm boot
2022             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2023             return;
2024         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2025             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2026             return;
2027 #endif
2028 
2029         case HCI_INIT_DONE:
2030             // set state if we came here by fall through
2031             hci_stack->substate = HCI_INIT_DONE;
2032             return;
2033 
2034         default:
2035             break;
2036     }
2037     hci_initializing_next_state();
2038 }
2039 
2040 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2041     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2042     bd_addr_t bd_address;
2043     (void)memcpy(&bd_address, conn->address, 6);
2044 
2045 #ifdef ENABLE_CLASSIC
2046     // cache needed data
2047     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2048 #endif
2049 
2050     // connection failed, remove entry
2051     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2052     btstack_memory_hci_connection_free( conn );
2053 
2054 #ifdef ENABLE_CLASSIC
2055     // notify client if dedicated bonding
2056     if (notify_dedicated_bonding_failed){
2057         log_info("hci notify_dedicated_bonding_failed");
2058         hci_emit_dedicated_bonding_result(bd_address, status);
2059     }
2060 
2061     // if authentication error, also delete link key
2062     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2063         gap_drop_link_key_for_bd_addr(bd_address);
2064     }
2065 #else
2066     UNUSED(status);
2067 #endif
2068 }
2069 
2070 #ifdef ENABLE_CLASSIC
2071 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2072     // SSP Controller
2073     if (features[6] & (1 << 3)){
2074         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2075     }
2076     // eSCO
2077     if (features[3] & (1<<7)){
2078         conn->remote_supported_features[0] |= 1;
2079     }
2080     // Extended features
2081     if (features[7] & (1<<7)){
2082         conn->remote_supported_features[0] |= 2;
2083     }
2084 }
2085 
2086 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2087     // SSP Host
2088     if (features[0] & (1 << 0)){
2089         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2090     }
2091     // SC Host
2092     if (features[0] & (1 << 3)){
2093         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2094     }
2095 }
2096 
2097 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2098     // SC Controller
2099     if (features[1] & (1 << 0)){
2100         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2101     }
2102 }
2103 
2104 static void hci_handle_remote_features_received(hci_connection_t * conn){
2105     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2106     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2107     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2108     if (conn->bonding_flags & BONDING_DEDICATED){
2109         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2110     }
2111 }
2112 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2113     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2114     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2115 }
2116 
2117 #endif
2118 
2119 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2120     // handle BT initialization
2121     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2122         hci_initializing_event_handler(packet, size);
2123     }
2124 
2125     // help with BT sleep
2126     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2127         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2128         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2129         hci_initializing_next_state();
2130     }
2131 }
2132 
2133 #ifdef ENABLE_CLASSIC
2134 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2135     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2136     conn->encryption_key_size = encryption_key_size;
2137 
2138     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2139         conn->requested_security_level = LEVEL_0;
2140         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2141         return;
2142     }
2143 
2144     // Request remote features if not already done
2145     hci_trigger_remote_features_for_connection(conn);
2146 
2147     // Request Authentication if not already done
2148     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2149     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2150 }
2151 #endif
2152 
2153 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2154     UNUSED(size);
2155 
2156     uint16_t manufacturer;
2157 #ifdef ENABLE_CLASSIC
2158     hci_con_handle_t handle;
2159     hci_connection_t * conn;
2160     uint8_t status;
2161 #endif
2162     // get num cmd packets - limit to 1 to reduce complexity
2163     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2164 
2165     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2166     switch (opcode){
2167         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2168             if (packet[5]) break;
2169             // terminate, name 248 chars
2170             packet[6+248] = 0;
2171             log_info("local name: %s", &packet[6]);
2172             break;
2173         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2174             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2175             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2176                 uint16_t acl_len = little_endian_read_16(packet, 6);
2177                 uint16_t sco_len = packet[8];
2178 
2179                 // determine usable ACL/SCO payload size
2180                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2181                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2182 
2183                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2184                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2185 
2186                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2187                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2188                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2189             }
2190             break;
2191         case HCI_OPCODE_HCI_READ_RSSI:
2192             if (packet[5] == ERROR_CODE_SUCCESS){
2193                 uint8_t event[5];
2194                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2195                 event[1] = 3;
2196                 (void)memcpy(&event[2], &packet[6], 3);
2197                 hci_emit_event(event, sizeof(event), 1);
2198             }
2199             break;
2200 #ifdef ENABLE_BLE
2201         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2202             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2203             hci_stack->le_acl_packets_total_num = packet[8];
2204             // determine usable ACL payload size
2205             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2206                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2207             }
2208             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2209             break;
2210 #endif
2211 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2212         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2213             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2214             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2215             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);
2216             break;
2217 #endif
2218 #ifdef ENABLE_LE_CENTRAL
2219         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2220             hci_stack->le_whitelist_capacity = packet[6];
2221             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2222             break;
2223 #endif
2224         case HCI_OPCODE_HCI_READ_BD_ADDR:
2225             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2226             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));
2227 #ifdef ENABLE_CLASSIC
2228             if (hci_stack->link_key_db){
2229                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2230             }
2231 #endif
2232             break;
2233 #ifdef ENABLE_CLASSIC
2234         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2235             hci_emit_discoverable_enabled(hci_stack->discoverable);
2236             break;
2237         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2238             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2239                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2240                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2241                 hci_emit_event(event, sizeof(event), 1);
2242             }
2243             break;
2244 #endif
2245         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2246             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2247 
2248 #ifdef ENABLE_CLASSIC
2249             // determine usable ACL packet types based on host buffer size and supported features
2250             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2251             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2252 #endif
2253             // Classic/LE
2254             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2255             break;
2256         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2257             manufacturer = little_endian_read_16(packet, 10);
2258             // map Cypress to Broadcom
2259             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2260                 log_info("Treat Cypress as Broadcom");
2261                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2262                 little_endian_store_16(packet, 10, manufacturer);
2263             }
2264             hci_stack->manufacturer = manufacturer;
2265             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2266             break;
2267         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2268             hci_stack->local_supported_commands[0] =
2269                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2270                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2271                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2272                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2273                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2274                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2275                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2276                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2277             hci_stack->local_supported_commands[1] =
2278                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2279                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2280                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2281                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2282                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2283             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2284             break;
2285 #ifdef ENABLE_CLASSIC
2286         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2287             if (packet[5]) return;
2288             hci_stack->synchronous_flow_control_enabled = 1;
2289             break;
2290         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2291             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2292             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2293             conn   = hci_connection_for_handle(handle);
2294             if (conn != NULL) {
2295                 uint8_t key_size = 0;
2296                 if (status == 0){
2297                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2298                     log_info("Handle %04x key Size: %u", handle, key_size);
2299                 } else {
2300                     key_size = 1;
2301                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2302                 }
2303                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2304             }
2305             break;
2306         // assert pairing complete event is emitted.
2307         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2308         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2309         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2310         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2311             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2312             // lookup connection by gap pairing addr
2313             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2314             if (conn == NULL) break;
2315             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2316             break;
2317 
2318 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2319         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2320         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2321             uint8_t event[67];
2322             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2323             event[1] = 65;
2324             (void)memset(&event[2], 0, 65);
2325             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2326                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2327                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2328                     event[2] = 3;
2329                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2330                 } else {
2331                     event[2] = 1;
2332                 }
2333             }
2334             hci_emit_event(event, sizeof(event), 0);
2335             break;
2336         }
2337 
2338         // note: only needed if user does not provide OOB data
2339         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2340             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2341             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2342             if (conn == NULL) break;
2343             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2344             break;
2345 #endif
2346 #endif
2347         default:
2348             break;
2349     }
2350 }
2351 
2352 #ifdef ENABLE_BLE
2353 static void event_handle_le_connection_complete(const uint8_t * packet){
2354 	bd_addr_t addr;
2355 	bd_addr_type_t addr_type;
2356 	hci_connection_t * conn;
2357 
2358 	// Connection management
2359 	reverse_bd_addr(&packet[8], addr);
2360 	addr_type = (bd_addr_type_t)packet[7];
2361 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2362 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2363 
2364 #ifdef ENABLE_LE_CENTRAL
2365 	// handle error: error is reported only to the initiator -> outgoing connection
2366 	if (packet[3]){
2367 
2368 		// handle cancelled outgoing connection
2369 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2370 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2371 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2372 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2373 		    // reset state
2374             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2375             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2376 			// get outgoing connection conn struct for direct connect
2377 			conn = gap_get_outgoing_connection();
2378 		}
2379 
2380 		// outgoing le connection establishment is done
2381 		if (conn){
2382 			// remove entry
2383 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2384 			btstack_memory_hci_connection_free( conn );
2385 		}
2386 		return;
2387 	}
2388 #endif
2389 
2390 	// on success, both hosts receive connection complete event
2391 	if (packet[6] == HCI_ROLE_MASTER){
2392 #ifdef ENABLE_LE_CENTRAL
2393 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2394 		// note: no hci_connection_t object exists yet for connect with whitelist
2395 		if (hci_is_le_connection_type(addr_type)){
2396 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2397 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2398 		}
2399 #endif
2400 	} else {
2401 #ifdef ENABLE_LE_PERIPHERAL
2402 		// if we're slave, it was an incoming connection, advertisements have stopped
2403 		hci_stack->le_advertisements_active = false;
2404 #endif
2405 	}
2406 
2407 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2408 	if (!conn){
2409 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2410 	}
2411 
2412 	// no memory, sorry.
2413 	if (!conn){
2414 		return;
2415 	}
2416 
2417 	conn->state = OPEN;
2418 	conn->role  = packet[6];
2419 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2420 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2421 
2422 #ifdef ENABLE_LE_PERIPHERAL
2423 	if (packet[6] == HCI_ROLE_SLAVE){
2424 		hci_update_advertisements_enabled_for_current_roles();
2425 	}
2426 #endif
2427 
2428     // init unenhanced att bearer mtu
2429     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2430     conn->att_connection.mtu_exchanged = false;
2431 
2432     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2433 
2434 	// restart timer
2435 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2436 	// btstack_run_loop_add_timer(&conn->timeout);
2437 
2438 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2439 
2440 	hci_emit_nr_connections_changed();
2441 }
2442 #endif
2443 
2444 #ifdef ENABLE_CLASSIC
2445 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){
2446     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2447     // LEVEL_4 is tested by l2cap
2448     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2449     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2450     if (level >= LEVEL_3){
2451         // MITM not possible without keyboard or display
2452         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2453         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2454 
2455         // MITM possible if one side has keyboard and the other has keyboard or display
2456         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2457         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2458 
2459         // MITM not possible if one side has only display and other side has no keyboard
2460         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2461         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2462     }
2463     // LEVEL 2 requires SSP, which is a given
2464     return true;
2465 }
2466 
2467 static bool btstack_is_null(uint8_t * data, uint16_t size){
2468     uint16_t i;
2469     for (i=0; i < size ; i++){
2470         if (data[i] != 0) {
2471             return false;
2472         }
2473     }
2474     return true;
2475 }
2476 
2477 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2478     // get requested security level
2479     gap_security_level_t requested_security_level = conn->requested_security_level;
2480     if (hci_stack->gap_secure_connections_only_mode){
2481         requested_security_level = LEVEL_4;
2482     }
2483 
2484     // assess security: LEVEL 4 requires SC
2485     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2486     if ((requested_security_level == LEVEL_4) &&
2487         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2488         !hci_remote_sc_enabled(conn)){
2489         log_info("Level 4 required, but SC not supported -> abort");
2490         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2491         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2492         return;
2493     }
2494 
2495     // assess security based on io capabilities
2496     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2497         // responder: fully validate io caps of both sides as well as OOB data
2498         bool security_possible = false;
2499         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2500 
2501 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2502         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2503         // so we merge the OOB data availability
2504         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2505         if (conn->classic_oob_c_192 != NULL){
2506             have_oob_data |= 1;
2507         }
2508         if (conn->classic_oob_c_256 != NULL){
2509             have_oob_data |= 2;
2510         }
2511         // for up to Level 3, either P-192 as well as P-256 will do
2512         // 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
2513         // if remote does not SC, we should not receive P-256 data either
2514         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2515             security_possible = true;
2516         }
2517         // for Level 4, P-256 is needed
2518         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2519             security_possible = true;
2520         }
2521 #endif
2522 
2523         if (security_possible == false){
2524             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2525             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2526             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2527             return;
2528         }
2529     } else {
2530         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2531 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2532 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2533         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2534             log_info("Level 3+ required, but no input/output -> abort");
2535             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2536             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2537             return;
2538         }
2539 #endif
2540 #endif
2541     }
2542 
2543 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2544     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2545         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2546     } else {
2547         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2548     }
2549 #endif
2550 }
2551 
2552 #endif
2553 
2554 static void event_handler(uint8_t *packet, uint16_t size){
2555 
2556     uint16_t event_length = packet[1];
2557 
2558     // assert packet is complete
2559     if (size != (event_length + 2u)){
2560         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2561         return;
2562     }
2563 
2564     bd_addr_type_t addr_type;
2565     hci_con_handle_t handle;
2566     hci_connection_t * conn;
2567     int i;
2568     int create_connection_cmd;
2569 
2570 #ifdef ENABLE_CLASSIC
2571     hci_link_type_t link_type;
2572     bd_addr_t addr;
2573 #endif
2574 
2575     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2576 
2577     switch (hci_event_packet_get_type(packet)) {
2578 
2579         case HCI_EVENT_COMMAND_COMPLETE:
2580             handle_command_complete_event(packet, size);
2581             break;
2582 
2583         case HCI_EVENT_COMMAND_STATUS:
2584             // get num cmd packets - limit to 1 to reduce complexity
2585             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2586 
2587             // check command status to detected failed outgoing connections
2588             create_connection_cmd = 0;
2589 #ifdef ENABLE_CLASSIC
2590             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2591                 create_connection_cmd = 1;
2592             }
2593 #endif
2594 #ifdef ENABLE_LE_CENTRAL
2595             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2596                 create_connection_cmd = 1;
2597             }
2598 #endif
2599             if (create_connection_cmd) {
2600                 uint8_t status = hci_event_command_status_get_status(packet);
2601                 addr_type = hci_stack->outgoing_addr_type;
2602                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2603                 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);
2604 
2605                 // reset outgoing address info
2606                 memset(hci_stack->outgoing_addr, 0, 6);
2607                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2608 
2609                 // on error
2610                 if (status != ERROR_CODE_SUCCESS){
2611 #ifdef ENABLE_LE_CENTRAL
2612                     if (hci_is_le_connection_type(addr_type)){
2613                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2614                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2615                     }
2616 #endif
2617                     // error => outgoing connection failed
2618                     if (conn != NULL){
2619                         hci_handle_connection_failed(conn, status);
2620                     }
2621                 }
2622             }
2623 
2624 #ifdef ENABLE_CLASSIC
2625             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2626                 uint8_t status = hci_event_command_status_get_status(packet);
2627                 log_info("command status (inquiry), status %x", status);
2628                 if (status == ERROR_CODE_SUCCESS) {
2629                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2630                 } else {
2631                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2632                 }
2633             }
2634 #endif
2635             break;
2636 
2637         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2638             if (size < 3) return;
2639             uint16_t num_handles = packet[2];
2640             if (size != (3u + num_handles * 4u)) return;
2641             uint16_t offset = 3;
2642             for (i=0; i<num_handles;i++){
2643                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2644                 offset += 2u;
2645                 uint16_t num_packets = little_endian_read_16(packet, offset);
2646                 offset += 2u;
2647 
2648                 conn = hci_connection_for_handle(handle);
2649                 if (!conn){
2650                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2651                     continue;
2652                 }
2653 
2654                 if (conn->num_packets_sent >= num_packets){
2655                     conn->num_packets_sent -= num_packets;
2656                 } else {
2657                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2658                     conn->num_packets_sent = 0;
2659                 }
2660                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2661 
2662 #ifdef ENABLE_CLASSIC
2663                 // For SCO, we do the can_send_now_check here
2664                 hci_notify_if_sco_can_send_now();
2665 #endif
2666             }
2667             break;
2668         }
2669 
2670 #ifdef ENABLE_CLASSIC
2671         case HCI_EVENT_INQUIRY_COMPLETE:
2672             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2673                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2674                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2675                 hci_emit_event(event, sizeof(event), 1);
2676             }
2677             break;
2678         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2679             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2680                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2681             }
2682             break;
2683         case HCI_EVENT_CONNECTION_REQUEST:
2684             reverse_bd_addr(&packet[2], addr);
2685             link_type = (hci_link_type_t) packet[11];
2686 
2687             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2688             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2689                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2690                 bd_addr_copy(hci_stack->decline_addr, addr);
2691                 break;
2692             }
2693 
2694             if (hci_stack->gap_classic_accept_callback != NULL){
2695                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2696                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2697                     bd_addr_copy(hci_stack->decline_addr, addr);
2698                     break;
2699                 }
2700             }
2701 
2702             // TODO: eval COD 8-10
2703             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2704             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2705             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2706             if (!conn) {
2707                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2708             }
2709             if (!conn) {
2710                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2711                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2712                 bd_addr_copy(hci_stack->decline_addr, addr);
2713                 break;
2714             }
2715             conn->role  = HCI_ROLE_SLAVE;
2716             conn->state = RECEIVED_CONNECTION_REQUEST;
2717             // store info about eSCO
2718             if (link_type == HCI_LINK_TYPE_ESCO){
2719                 conn->remote_supported_features[0] |= 1;
2720             }
2721             hci_run();
2722             break;
2723 
2724         case HCI_EVENT_CONNECTION_COMPLETE:
2725             // Connection management
2726             reverse_bd_addr(&packet[5], addr);
2727             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2728             addr_type = BD_ADDR_TYPE_ACL;
2729             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2730             if (conn) {
2731                 if (!packet[2]){
2732                     conn->state = OPEN;
2733                     conn->con_handle = little_endian_read_16(packet, 3);
2734 
2735                     // queue set supervision timeout if we're master
2736                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2737                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2738                     }
2739 
2740                     // restart timer
2741                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2742                     btstack_run_loop_add_timer(&conn->timeout);
2743 
2744                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2745 
2746                     hci_emit_nr_connections_changed();
2747                 } else {
2748                     // connection failed
2749                     hci_handle_connection_failed(conn, packet[2]);
2750                 }
2751             }
2752             break;
2753 
2754         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2755             reverse_bd_addr(&packet[5], addr);
2756             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2757             if (packet[2]){
2758                 // connection failed
2759                 break;
2760             }
2761             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2762             if (!conn) {
2763                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2764             }
2765             if (!conn) {
2766                 break;
2767             }
2768             conn->state = OPEN;
2769             conn->con_handle = little_endian_read_16(packet, 3);
2770 
2771 #ifdef ENABLE_SCO_OVER_HCI
2772             // update SCO
2773             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2774                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2775             }
2776             // trigger can send now
2777             if (hci_have_usb_transport()){
2778                 hci_stack->sco_can_send_now = true;
2779             }
2780 #endif
2781 #ifdef HAVE_SCO_TRANSPORT
2782             // configure sco transport
2783             if (hci_stack->sco_transport != NULL){
2784                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2785                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2786             }
2787 #endif
2788             break;
2789 
2790         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2791             handle = little_endian_read_16(packet, 3);
2792             conn = hci_connection_for_handle(handle);
2793             if (!conn) break;
2794             if (!packet[2]){
2795                 const uint8_t * features = &packet[5];
2796                 hci_handle_remote_features_page_0(conn, features);
2797 
2798                 // read extended features if possible
2799                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2800                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2801                     break;
2802                 }
2803             }
2804             hci_handle_remote_features_received(conn);
2805             break;
2806 
2807         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2808             handle = little_endian_read_16(packet, 3);
2809             conn = hci_connection_for_handle(handle);
2810             if (!conn) break;
2811             // status = ok, page = 1
2812             if (!packet[2]) {
2813                 uint8_t page_number = packet[5];
2814                 uint8_t maximum_page_number = packet[6];
2815                 const uint8_t * features = &packet[7];
2816                 bool done = false;
2817                 switch (page_number){
2818                     case 1:
2819                         hci_handle_remote_features_page_1(conn, features);
2820                         if (maximum_page_number >= 2){
2821                             // get Secure Connections (Controller) from Page 2 if available
2822                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2823                         } else {
2824                             // otherwise, assume SC (Controller) == SC (Host)
2825                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2826                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2827                             }
2828                             done = true;
2829                         }
2830                         break;
2831                     case 2:
2832                         hci_handle_remote_features_page_2(conn, features);
2833                         done = true;
2834                         break;
2835                     default:
2836                         break;
2837                 }
2838                 if (!done) break;
2839             }
2840             hci_handle_remote_features_received(conn);
2841             break;
2842 
2843         case HCI_EVENT_LINK_KEY_REQUEST:
2844 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2845             hci_event_link_key_request_get_bd_addr(packet, addr);
2846             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2847             if (!conn) break;
2848 
2849             // lookup link key in db if not cached
2850             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2851                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2852             }
2853 
2854             // response sent by hci_run()
2855             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2856 #endif
2857             break;
2858 
2859         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2860             hci_event_link_key_request_get_bd_addr(packet, addr);
2861             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2862             if (!conn) break;
2863 
2864             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2865 
2866             // CVE-2020-26555: ignore NULL link key
2867             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2868             if (btstack_is_null(&packet[8], 16)) break;
2869 
2870             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2871             // Change Connection Encryption keeps link key type
2872             if (link_key_type != CHANGED_COMBINATION_KEY){
2873                 conn->link_key_type = link_key_type;
2874             }
2875 
2876             // cache link key. link keys stored in little-endian format for legacy reasons
2877             memcpy(&conn->link_key, &packet[8], 16);
2878 
2879             // only store link key:
2880             // - if bondable enabled
2881             if (hci_stack->bondable == false) break;
2882             // - if security level sufficient
2883             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2884             // - for SSP, also check if remote side requested bonding as well
2885             if (conn->link_key_type != COMBINATION_KEY){
2886                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2887                 if (!remote_bonding){
2888                     break;
2889                 }
2890             }
2891             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2892             break;
2893         }
2894 
2895         case HCI_EVENT_PIN_CODE_REQUEST:
2896             hci_event_pin_code_request_get_bd_addr(packet, addr);
2897             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2898             if (!conn) break;
2899 
2900             hci_pairing_started(conn, false);
2901             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2902             if (!hci_stack->bondable ){
2903                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2904                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2905                 hci_run();
2906                 return;
2907             }
2908             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2909             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2910                 log_info("Level 4 required, but SC not supported -> abort");
2911                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2912                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2913                 hci_run();
2914                 return;
2915             }
2916             break;
2917 
2918         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2919             hci_event_io_capability_response_get_bd_addr(packet, addr);
2920             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2921             if (!conn) break;
2922 
2923             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2924             hci_pairing_started(conn, true);
2925             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2926             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2927 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2928             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2929 #endif
2930             break;
2931 
2932         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2933             hci_event_io_capability_response_get_bd_addr(packet, addr);
2934             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2935             if (!conn) break;
2936 
2937             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2938             hci_connection_timestamp(conn);
2939             hci_pairing_started(conn, true);
2940             break;
2941 
2942 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2943         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2944             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2945             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2946             if (!conn) break;
2947 
2948             hci_connection_timestamp(conn);
2949 
2950             hci_pairing_started(conn, true);
2951 
2952             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2953             break;
2954 #endif
2955 
2956         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2957             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2958             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2959             if (!conn) break;
2960             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2961                 if (hci_stack->ssp_auto_accept){
2962                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2963                 };
2964             } else {
2965                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2966                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2967                 // don't forward event to app
2968                 hci_run();
2969                 return;
2970             }
2971             break;
2972 
2973         case HCI_EVENT_USER_PASSKEY_REQUEST:
2974             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2975             if (hci_stack->ssp_auto_accept){
2976                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2977             };
2978             break;
2979 
2980         case HCI_EVENT_MODE_CHANGE:
2981             handle = hci_event_mode_change_get_handle(packet);
2982             conn = hci_connection_for_handle(handle);
2983             if (!conn) break;
2984             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2985             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2986             break;
2987 #endif
2988 
2989         case HCI_EVENT_ENCRYPTION_CHANGE:
2990             handle = hci_event_encryption_change_get_connection_handle(packet);
2991             conn = hci_connection_for_handle(handle);
2992             if (!conn) break;
2993             if (hci_event_encryption_change_get_status(packet) == 0u) {
2994                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2995                 if (encryption_enabled){
2996                     if (hci_is_le_connection(conn)){
2997                         // For LE, we accept connection as encrypted
2998                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2999                     }
3000 #ifdef ENABLE_CLASSIC
3001                     else {
3002 
3003                         // dedicated bonding: send result and disconnect
3004                         if (conn->bonding_flags & BONDING_DEDICATED){
3005                             conn->bonding_flags &= ~BONDING_DEDICATED;
3006                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3007                             conn->bonding_status = packet[2];
3008                             break;
3009                         }
3010 
3011                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3012                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3013                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3014                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3015                             log_info("SC during pairing, but only E0 now -> abort");
3016                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3017                             break;
3018                         }
3019 
3020                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3021                         if (connected_uses_aes_ccm){
3022                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3023                         }
3024 
3025 #ifdef ENABLE_TESTING_SUPPORT
3026                         // work around for issue with PTS dongle
3027                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3028 #endif
3029 
3030                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3031                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3032                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3033                         } else {
3034                             // if not, pretend everything is perfect
3035                             hci_handle_read_encryption_key_size_complete(conn, 16);
3036                         }
3037                     }
3038 #endif
3039                 } else {
3040                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3041                 }
3042             }
3043 
3044             break;
3045 
3046 #ifdef ENABLE_CLASSIC
3047         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3048             handle = hci_event_authentication_complete_get_connection_handle(packet);
3049             conn = hci_connection_for_handle(handle);
3050             if (!conn) break;
3051 
3052             // clear authentication active flag
3053             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3054             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3055 
3056             // authenticated only if auth status == 0
3057             if (hci_event_authentication_complete_get_status(packet) == 0){
3058                 // authenticated
3059                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3060 
3061                 // If not already encrypted, start encryption
3062                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3063                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3064                     break;
3065                 }
3066             }
3067 
3068             // emit updated security level
3069             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3070             break;
3071 
3072         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3073             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3074             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3075             if (!conn) break;
3076 
3077             // treat successfully paired connection as authenticated
3078             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3079                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3080             }
3081 
3082             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3083             break;
3084 #endif
3085 
3086         // HCI_EVENT_DISCONNECTION_COMPLETE
3087         // has been split, to first notify stack before shutting connection down
3088         // see end of function, too.
3089         case HCI_EVENT_DISCONNECTION_COMPLETE:
3090             if (packet[2]) break;   // status != 0
3091             handle = little_endian_read_16(packet, 3);
3092             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3093             if (hci_stack->acl_fragmentation_total_size > 0u) {
3094                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3095                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3096                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3097                     hci_stack->acl_fragmentation_total_size = 0;
3098                     hci_stack->acl_fragmentation_pos = 0;
3099                     if (release_buffer){
3100                         hci_release_packet_buffer();
3101                     }
3102                 }
3103             }
3104 
3105             conn = hci_connection_for_handle(handle);
3106             if (!conn) break;
3107 #ifdef ENABLE_CLASSIC
3108             // pairing failed if it was ongoing
3109             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3110 #endif
3111 
3112             // emit dedicatd bonding event
3113             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3114                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3115             }
3116 
3117             // mark connection for shutdown, stop timers, reset state
3118             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3119             hci_connection_stop_timer(conn);
3120             hci_connection_init(conn);
3121 
3122 #ifdef ENABLE_BLE
3123 #ifdef ENABLE_LE_PERIPHERAL
3124             // re-enable advertisements for le connections if active
3125             if (hci_is_le_connection(conn)){
3126                 hci_update_advertisements_enabled_for_current_roles();
3127             }
3128 #endif
3129 #endif
3130             break;
3131 
3132         case HCI_EVENT_HARDWARE_ERROR:
3133             log_error("Hardware Error: 0x%02x", packet[2]);
3134             if (hci_stack->hardware_error_callback){
3135                 (*hci_stack->hardware_error_callback)(packet[2]);
3136             } else {
3137                 // if no special requests, just reboot stack
3138                 hci_power_control_off();
3139                 hci_power_control_on();
3140             }
3141             break;
3142 
3143 #ifdef ENABLE_CLASSIC
3144         case HCI_EVENT_ROLE_CHANGE:
3145             if (packet[2]) break;   // status != 0
3146             reverse_bd_addr(&packet[3], addr);
3147             addr_type = BD_ADDR_TYPE_ACL;
3148             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3149             if (!conn) break;
3150             conn->role = packet[9];
3151             break;
3152 #endif
3153 
3154         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3155             // release packet buffer only for asynchronous transport and if there are not further fragements
3156             if (hci_transport_synchronous()) {
3157                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3158                 return; // instead of break: to avoid re-entering hci_run()
3159             }
3160             hci_stack->acl_fragmentation_tx_active = 0;
3161             if (hci_stack->acl_fragmentation_total_size) break;
3162             hci_release_packet_buffer();
3163 
3164             // L2CAP receives this event via the hci_emit_event below
3165 
3166 #ifdef ENABLE_CLASSIC
3167             // For SCO, we do the can_send_now_check here
3168             hci_notify_if_sco_can_send_now();
3169 #endif
3170             break;
3171 
3172 #ifdef ENABLE_CLASSIC
3173         case HCI_EVENT_SCO_CAN_SEND_NOW:
3174             // For SCO, we do the can_send_now_check here
3175             hci_stack->sco_can_send_now = true;
3176             hci_notify_if_sco_can_send_now();
3177             return;
3178 
3179         // explode inquriy results for easier consumption
3180         case HCI_EVENT_INQUIRY_RESULT:
3181         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3182         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3183             gap_inquiry_explode(packet, size);
3184             break;
3185 #endif
3186 
3187 #ifdef ENABLE_BLE
3188         case HCI_EVENT_LE_META:
3189             switch (packet[2]){
3190 #ifdef ENABLE_LE_CENTRAL
3191                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3192                     // log_info("advertising report received");
3193                     if (!hci_stack->le_scanning_enabled) break;
3194                     le_handle_advertisement_report(packet, size);
3195                     break;
3196 #endif
3197                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3198 					event_handle_le_connection_complete(packet);
3199                     break;
3200 
3201                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3202                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3203                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3204                     conn = hci_connection_for_handle(handle);
3205                     if (!conn) break;
3206                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3207                     break;
3208 
3209                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3210                     // connection
3211                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3212                     conn = hci_connection_for_handle(handle);
3213                     if (conn) {
3214                         // read arguments
3215                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3216                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3217                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3218                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3219 
3220                         // validate against current connection parameter range
3221                         le_connection_parameter_range_t existing_range;
3222                         gap_get_connection_parameter_range(&existing_range);
3223                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3224                         if (update_parameter){
3225                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3226                             conn->le_conn_interval_min = le_conn_interval_min;
3227                             conn->le_conn_interval_max = le_conn_interval_max;
3228                             conn->le_conn_latency = le_conn_latency;
3229                             conn->le_supervision_timeout = le_supervision_timeout;
3230                         } else {
3231                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3232                         }
3233                     }
3234                     break;
3235 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3236                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3237                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3238                     conn = hci_connection_for_handle(handle);
3239                     if (conn) {
3240                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3241                     }
3242                     break;
3243 #endif
3244                 default:
3245                     break;
3246             }
3247             break;
3248 #endif
3249         case HCI_EVENT_VENDOR_SPECIFIC:
3250             // Vendor specific commands often create vendor specific event instead of num completed packets
3251             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3252             switch (hci_stack->manufacturer){
3253                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3254                     hci_stack->num_cmd_packets = 1;
3255                     break;
3256                 default:
3257                     break;
3258             }
3259             break;
3260         default:
3261             break;
3262     }
3263 
3264     handle_event_for_current_stack_state(packet, size);
3265 
3266     // notify upper stack
3267 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3268 
3269     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3270     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3271 		handle = little_endian_read_16(packet, 3);
3272 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3273 		// discard connection if app did not trigger a reconnect in the event handler
3274 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3275 			hci_shutdown_connection(aConn);
3276 		}
3277     }
3278 
3279 	// execute main loop
3280 	hci_run();
3281 }
3282 
3283 #ifdef ENABLE_CLASSIC
3284 
3285 #ifdef ENABLE_SCO_OVER_HCI
3286 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3287 static void sco_schedule_tx(hci_connection_t * conn);
3288 
3289 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3290     log_debug("SCO TX Timeout");
3291     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3292     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3293     if (!conn) return;
3294 
3295     // trigger send
3296     conn->sco_tx_ready = 1;
3297     // extra packet if CVSD but SCO buffer is too short
3298     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3299         conn->sco_tx_ready++;
3300     }
3301     hci_notify_if_sco_can_send_now();
3302 }
3303 
3304 
3305 #define SCO_TX_AFTER_RX_MS (6)
3306 
3307 static void sco_schedule_tx(hci_connection_t * conn){
3308 
3309     uint32_t now = btstack_run_loop_get_time_ms();
3310     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3311     int time_delta_ms = sco_tx_ms - now;
3312 
3313     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3314 
3315     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3316     btstack_run_loop_remove_timer(timer);
3317     btstack_run_loop_set_timer(timer, time_delta_ms);
3318     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3319     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3320     btstack_run_loop_add_timer(timer);
3321 }
3322 #endif
3323 
3324 static void sco_handler(uint8_t * packet, uint16_t size){
3325     // lookup connection struct
3326     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3327     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3328     if (!conn) return;
3329 
3330 #ifdef ENABLE_SCO_OVER_HCI
3331     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3332     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3333         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3334             packet[2] = 0x3c;
3335             memmove(&packet[3], &packet[23], 63);
3336             size = 63;
3337         }
3338     }
3339 
3340     if (hci_have_usb_transport()){
3341         // Nothing to do
3342     } else {
3343         // 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);
3344         if (hci_stack->synchronous_flow_control_enabled == 0){
3345             uint32_t now = btstack_run_loop_get_time_ms();
3346 
3347             if (!conn->sco_rx_valid){
3348                 // ignore first 10 packets
3349                 conn->sco_rx_count++;
3350                 // log_debug("sco rx count %u", conn->sco_rx_count);
3351                 if (conn->sco_rx_count == 10) {
3352                     // use first timestamp as is and pretent it just started
3353                     conn->sco_rx_ms = now;
3354                     conn->sco_rx_valid = 1;
3355                     conn->sco_rx_count = 0;
3356                     sco_schedule_tx(conn);
3357                 }
3358             } else {
3359                 // track expected arrival timme
3360                 conn->sco_rx_count++;
3361                 conn->sco_rx_ms += 7;
3362                 int delta = (int32_t) (now - conn->sco_rx_ms);
3363                 if (delta > 0){
3364                     conn->sco_rx_ms++;
3365                 }
3366                 // log_debug("sco rx %u", conn->sco_rx_ms);
3367                 sco_schedule_tx(conn);
3368             }
3369         }
3370     }
3371 #endif
3372 
3373     // deliver to app
3374     if (hci_stack->sco_packet_handler) {
3375         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3376     }
3377 
3378 #ifdef HAVE_SCO_TRANSPORT
3379     // We can send one packet for each received packet
3380     conn->sco_tx_ready++;
3381     hci_notify_if_sco_can_send_now();
3382 #endif
3383 
3384 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3385     conn->num_packets_completed++;
3386     hci_stack->host_completed_packets = 1;
3387     hci_run();
3388 #endif
3389 }
3390 #endif
3391 
3392 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3393     hci_dump_packet(packet_type, 1, packet, size);
3394     switch (packet_type) {
3395         case HCI_EVENT_PACKET:
3396             event_handler(packet, size);
3397             break;
3398         case HCI_ACL_DATA_PACKET:
3399             acl_handler(packet, size);
3400             break;
3401 #ifdef ENABLE_CLASSIC
3402         case HCI_SCO_DATA_PACKET:
3403             sco_handler(packet, size);
3404             break;
3405 #endif
3406         default:
3407             break;
3408     }
3409 }
3410 
3411 /**
3412  * @brief Add event packet handler.
3413  */
3414 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3415     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3416 }
3417 
3418 /**
3419  * @brief Remove event packet handler.
3420  */
3421 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3422     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3423 }
3424 
3425 /** Register HCI packet handlers */
3426 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3427     hci_stack->acl_packet_handler = handler;
3428 }
3429 
3430 #ifdef ENABLE_CLASSIC
3431 /**
3432  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3433  */
3434 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3435     hci_stack->sco_packet_handler = handler;
3436 }
3437 #endif
3438 
3439 static void hci_state_reset(void){
3440     // no connections yet
3441     hci_stack->connections = NULL;
3442 
3443     // keep discoverable/connectable as this has been requested by the client(s)
3444     // hci_stack->discoverable = 0;
3445     // hci_stack->connectable = 0;
3446     // hci_stack->bondable = 1;
3447     // hci_stack->own_addr_type = 0;
3448 
3449     // buffer is free
3450     hci_stack->hci_packet_buffer_reserved = false;
3451 
3452     // no pending cmds
3453     hci_stack->decline_reason = 0;
3454 
3455     hci_stack->secure_connections_active = false;
3456 
3457 #ifdef ENABLE_CLASSIC
3458     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3459     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3460 
3461     hci_stack->gap_tasks =
3462             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3463             GAP_TASK_SET_CLASS_OF_DEVICE |
3464             GAP_TASK_SET_LOCAL_NAME |
3465             GAP_TASK_SET_EIR_DATA |
3466             GAP_TASK_WRITE_SCAN_ENABLE |
3467             GAP_TASK_WRITE_PAGE_TIMEOUT;
3468 #endif
3469 
3470 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3471     hci_stack->classic_read_local_oob_data = false;
3472     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3473 #endif
3474 
3475     // LE
3476 #ifdef ENABLE_BLE
3477     memset(hci_stack->le_random_address, 0, 6);
3478     hci_stack->le_random_address_set = 0;
3479 #endif
3480 #ifdef ENABLE_LE_CENTRAL
3481     hci_stack->le_scanning_active  = false;
3482     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3483     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3484     hci_stack->le_whitelist_capacity = 0;
3485 #endif
3486 #ifdef ENABLE_LE_PERIPHERAL
3487     hci_stack->le_advertisements_active = false;
3488     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3489         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3490     }
3491     if (hci_stack->le_advertisements_data != NULL){
3492         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3493     }
3494 #endif
3495 }
3496 
3497 #ifdef ENABLE_CLASSIC
3498 /**
3499  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3500  */
3501 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3502     // store and open remote device db
3503     hci_stack->link_key_db = link_key_db;
3504     if (hci_stack->link_key_db) {
3505         hci_stack->link_key_db->open();
3506     }
3507 }
3508 #endif
3509 
3510 void hci_init(const hci_transport_t *transport, const void *config){
3511 
3512 #ifdef HAVE_MALLOC
3513     if (!hci_stack) {
3514         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3515     }
3516 #else
3517     hci_stack = &hci_stack_static;
3518 #endif
3519     memset(hci_stack, 0, sizeof(hci_stack_t));
3520 
3521     // reference to use transport layer implementation
3522     hci_stack->hci_transport = transport;
3523 
3524     // reference to used config
3525     hci_stack->config = config;
3526 
3527     // setup pointer for outgoing packet buffer
3528     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3529 
3530     // max acl payload size defined in config.h
3531     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3532 
3533     // register packet handlers with transport
3534     transport->register_packet_handler(&packet_handler);
3535 
3536     hci_stack->state = HCI_STATE_OFF;
3537 
3538     // class of device
3539     hci_stack->class_of_device = 0x007a020c; // Smartphone
3540 
3541     // bondable by default
3542     hci_stack->bondable = 1;
3543 
3544 #ifdef ENABLE_CLASSIC
3545     // classic name
3546     hci_stack->local_name = default_classic_name;
3547 
3548     // Master slave policy
3549     hci_stack->master_slave_policy = 1;
3550 
3551     // Allow Role Switch
3552     hci_stack->allow_role_switch = 1;
3553 
3554     // Default / minimum security level = 2
3555     hci_stack->gap_security_level = LEVEL_2;
3556 
3557     // Default Security Mode 4
3558     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3559 
3560     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3561     hci_stack->gap_required_encyrption_key_size = 7;
3562 
3563     // Link Supervision Timeout
3564     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3565 
3566 #endif
3567 
3568     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3569     hci_stack->ssp_enable = 1;
3570     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3571     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3572     hci_stack->ssp_auto_accept = 1;
3573 
3574     // Secure Connections: enable (requires support from Controller)
3575     hci_stack->secure_connections_enable = true;
3576 
3577     // voice setting - signed 16 bit pcm data with CVSD over the air
3578     hci_stack->sco_voice_setting = 0x60;
3579 
3580 #ifdef ENABLE_LE_CENTRAL
3581     // connection parameter to use for outgoing connections
3582     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3583     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3584     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3585     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3586     hci_stack->le_connection_latency      = 4;         // 4
3587     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3588     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3589     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3590 
3591     // default LE Scanning
3592     hci_stack->le_scan_type     =   0x1; // active
3593     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3594     hci_stack->le_scan_window   =  0x30; //  30 ms
3595 #endif
3596 
3597 #ifdef ENABLE_LE_PERIPHERAL
3598     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3599 #endif
3600 
3601     // connection parameter range used to answer connection parameter update requests in l2cap
3602     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3603     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3604     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3605     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3606     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3607     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3608 
3609     hci_state_reset();
3610 }
3611 
3612 void hci_deinit(void){
3613 #ifdef HAVE_MALLOC
3614     if (hci_stack) {
3615         free(hci_stack);
3616     }
3617 #endif
3618     hci_stack = NULL;
3619 
3620 #ifdef ENABLE_CLASSIC
3621     disable_l2cap_timeouts = 0;
3622 #endif
3623 }
3624 
3625 /**
3626  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3627  */
3628 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3629     hci_stack->chipset = chipset_driver;
3630 
3631     // reset chipset driver - init is also called on power_up
3632     if (hci_stack->chipset && hci_stack->chipset->init){
3633         hci_stack->chipset->init(hci_stack->config);
3634     }
3635 }
3636 
3637 /**
3638  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3639  */
3640 void hci_set_control(const btstack_control_t *hardware_control){
3641     // references to used control implementation
3642     hci_stack->control = hardware_control;
3643     // init with transport config
3644     hardware_control->init(hci_stack->config);
3645 }
3646 
3647 static void hci_discard_connections(void){
3648     btstack_linked_list_iterator_t lit;
3649     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3650     while (btstack_linked_list_iterator_has_next(&lit)){
3651         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3652         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3653         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3654         hci_shutdown_connection(connection);
3655     }
3656 }
3657 
3658 void hci_close(void){
3659 
3660 #ifdef ENABLE_CLASSIC
3661     // close remote device db
3662     if (hci_stack->link_key_db) {
3663         hci_stack->link_key_db->close();
3664     }
3665 #endif
3666 
3667     hci_discard_connections();
3668 
3669     hci_power_control(HCI_POWER_OFF);
3670 
3671 #ifdef HAVE_MALLOC
3672     free(hci_stack);
3673 #endif
3674     hci_stack = NULL;
3675 }
3676 
3677 #ifdef HAVE_SCO_TRANSPORT
3678 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3679     hci_stack->sco_transport = sco_transport;
3680     sco_transport->register_packet_handler(&packet_handler);
3681 }
3682 #endif
3683 
3684 #ifdef ENABLE_CLASSIC
3685 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3686     // validate ranage and set
3687     if (encryption_key_size < 7)  return;
3688     if (encryption_key_size > 16) return;
3689     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3690 }
3691 
3692 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3693     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3694         hci_stack->gap_security_mode = security_mode;
3695         return ERROR_CODE_SUCCESS;
3696     } else {
3697         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3698     }
3699 }
3700 
3701 gap_security_mode_t gap_get_security_mode(void){
3702     return hci_stack->gap_security_mode;
3703 }
3704 
3705 void gap_set_security_level(gap_security_level_t security_level){
3706     hci_stack->gap_security_level = security_level;
3707 }
3708 
3709 gap_security_level_t gap_get_security_level(void){
3710     if (hci_stack->gap_secure_connections_only_mode){
3711         return LEVEL_4;
3712     }
3713     return hci_stack->gap_security_level;
3714 }
3715 
3716 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3717     hci_stack->gap_minimal_service_security_level = security_level;
3718 }
3719 
3720 void gap_set_secure_connections_only_mode(bool enable){
3721     hci_stack->gap_secure_connections_only_mode = enable;
3722 }
3723 
3724 bool gap_get_secure_connections_only_mode(void){
3725     return hci_stack->gap_secure_connections_only_mode;
3726 }
3727 #endif
3728 
3729 #ifdef ENABLE_CLASSIC
3730 void gap_set_class_of_device(uint32_t class_of_device){
3731     hci_stack->class_of_device = class_of_device;
3732     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3733     hci_run();
3734 }
3735 
3736 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3737     hci_stack->default_link_policy_settings = default_link_policy_settings;
3738     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3739     hci_run();
3740 }
3741 
3742 void gap_set_allow_role_switch(bool allow_role_switch){
3743     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3744 }
3745 
3746 uint8_t hci_get_allow_role_switch(void){
3747     return  hci_stack->allow_role_switch;
3748 }
3749 
3750 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3751     hci_stack->link_supervision_timeout = link_supervision_timeout;
3752 }
3753 
3754 void hci_disable_l2cap_timeout_check(void){
3755     disable_l2cap_timeouts = 1;
3756 }
3757 #endif
3758 
3759 #ifndef HAVE_HOST_CONTROLLER_API
3760 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3761 void hci_set_bd_addr(bd_addr_t addr){
3762     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3763     hci_stack->custom_bd_addr_set = 1;
3764 }
3765 #endif
3766 
3767 // State-Module-Driver overview
3768 // state                    module  low-level
3769 // HCI_STATE_OFF             off      close
3770 // HCI_STATE_INITIALIZING,   on       open
3771 // HCI_STATE_WORKING,        on       open
3772 // HCI_STATE_HALTING,        on       open
3773 // HCI_STATE_SLEEPING,    off/sleep   close
3774 // HCI_STATE_FALLING_ASLEEP  on       open
3775 
3776 static int hci_power_control_on(void){
3777 
3778     // power on
3779     int err = 0;
3780     if (hci_stack->control && hci_stack->control->on){
3781         err = (*hci_stack->control->on)();
3782     }
3783     if (err){
3784         log_error( "POWER_ON failed");
3785         hci_emit_hci_open_failed();
3786         return err;
3787     }
3788 
3789     // int chipset driver
3790     if (hci_stack->chipset && hci_stack->chipset->init){
3791         hci_stack->chipset->init(hci_stack->config);
3792     }
3793 
3794     // init transport
3795     if (hci_stack->hci_transport->init){
3796         hci_stack->hci_transport->init(hci_stack->config);
3797     }
3798 
3799     // open transport
3800     err = hci_stack->hci_transport->open();
3801     if (err){
3802         log_error( "HCI_INIT failed, turning Bluetooth off again");
3803         if (hci_stack->control && hci_stack->control->off){
3804             (*hci_stack->control->off)();
3805         }
3806         hci_emit_hci_open_failed();
3807         return err;
3808     }
3809     return 0;
3810 }
3811 
3812 static void hci_power_control_off(void){
3813 
3814     log_info("hci_power_control_off");
3815 
3816     // close low-level device
3817     hci_stack->hci_transport->close();
3818 
3819     log_info("hci_power_control_off - hci_transport closed");
3820 
3821     // power off
3822     if (hci_stack->control && hci_stack->control->off){
3823         (*hci_stack->control->off)();
3824     }
3825 
3826     log_info("hci_power_control_off - control closed");
3827 
3828     hci_stack->state = HCI_STATE_OFF;
3829 }
3830 
3831 static void hci_power_control_sleep(void){
3832 
3833     log_info("hci_power_control_sleep");
3834 
3835 #if 0
3836     // don't close serial port during sleep
3837 
3838     // close low-level device
3839     hci_stack->hci_transport->close(hci_stack->config);
3840 #endif
3841 
3842     // sleep mode
3843     if (hci_stack->control && hci_stack->control->sleep){
3844         (*hci_stack->control->sleep)();
3845     }
3846 
3847     hci_stack->state = HCI_STATE_SLEEPING;
3848 }
3849 
3850 static int hci_power_control_wake(void){
3851 
3852     log_info("hci_power_control_wake");
3853 
3854     // wake on
3855     if (hci_stack->control && hci_stack->control->wake){
3856         (*hci_stack->control->wake)();
3857     }
3858 
3859 #if 0
3860     // open low-level device
3861     int err = hci_stack->hci_transport->open(hci_stack->config);
3862     if (err){
3863         log_error( "HCI_INIT failed, turning Bluetooth off again");
3864         if (hci_stack->control && hci_stack->control->off){
3865             (*hci_stack->control->off)();
3866         }
3867         hci_emit_hci_open_failed();
3868         return err;
3869     }
3870 #endif
3871 
3872     return 0;
3873 }
3874 
3875 static void hci_power_transition_to_initializing(void){
3876     // set up state machine
3877     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3878     hci_stack->hci_packet_buffer_reserved = false;
3879     hci_stack->state = HCI_STATE_INITIALIZING;
3880     hci_stack->substate = HCI_INIT_SEND_RESET;
3881 }
3882 
3883 // returns error
3884 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3885     int err;
3886     switch (power_mode){
3887         case HCI_POWER_ON:
3888             err = hci_power_control_on();
3889             if (err != 0) {
3890                 log_error("hci_power_control_on() error %d", err);
3891                 return err;
3892             }
3893             hci_power_transition_to_initializing();
3894             break;
3895         case HCI_POWER_OFF:
3896             // do nothing
3897             break;
3898         case HCI_POWER_SLEEP:
3899             // do nothing (with SLEEP == OFF)
3900             break;
3901         default:
3902             btstack_assert(false);
3903             break;
3904     }
3905     return ERROR_CODE_SUCCESS;
3906 }
3907 
3908 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3909     switch (power_mode){
3910         case HCI_POWER_ON:
3911             // do nothing
3912             break;
3913         case HCI_POWER_OFF:
3914             // no connections yet, just turn it off
3915             hci_power_control_off();
3916             break;
3917         case HCI_POWER_SLEEP:
3918             // no connections yet, just turn it off
3919             hci_power_control_sleep();
3920             break;
3921         default:
3922             btstack_assert(false);
3923             break;
3924     }
3925     return ERROR_CODE_SUCCESS;
3926 }
3927 
3928 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3929     switch (power_mode){
3930         case HCI_POWER_ON:
3931             // do nothing
3932             break;
3933         case HCI_POWER_OFF:
3934             // see hci_run
3935             hci_stack->state = HCI_STATE_HALTING;
3936             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3937             break;
3938         case HCI_POWER_SLEEP:
3939             // see hci_run
3940             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3941             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3942             break;
3943         default:
3944             btstack_assert(false);
3945             break;
3946     }
3947     return ERROR_CODE_SUCCESS;
3948 }
3949 
3950 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3951     switch (power_mode){
3952         case HCI_POWER_ON:
3953             hci_power_transition_to_initializing();
3954             break;
3955         case HCI_POWER_OFF:
3956             // do nothing
3957             break;
3958         case HCI_POWER_SLEEP:
3959             // see hci_run
3960             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3961             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3962             break;
3963         default:
3964             btstack_assert(false);
3965             break;
3966     }
3967     return ERROR_CODE_SUCCESS;
3968 }
3969 
3970 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3971     switch (power_mode){
3972         case HCI_POWER_ON:
3973             hci_power_transition_to_initializing();
3974             break;
3975         case HCI_POWER_OFF:
3976             // see hci_run
3977             hci_stack->state = HCI_STATE_HALTING;
3978             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3979             break;
3980         case HCI_POWER_SLEEP:
3981             // do nothing
3982             break;
3983         default:
3984             btstack_assert(false);
3985             break;
3986     }
3987     return ERROR_CODE_SUCCESS;
3988 }
3989 
3990 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3991     int err;
3992     switch (power_mode){
3993         case HCI_POWER_ON:
3994             err = hci_power_control_wake();
3995             if (err) return err;
3996             hci_power_transition_to_initializing();
3997             break;
3998         case HCI_POWER_OFF:
3999             hci_stack->state = HCI_STATE_HALTING;
4000             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4001             break;
4002         case HCI_POWER_SLEEP:
4003             // do nothing
4004             break;
4005         default:
4006             btstack_assert(false);
4007             break;
4008     }
4009     return ERROR_CODE_SUCCESS;
4010 }
4011 
4012 int hci_power_control(HCI_POWER_MODE power_mode){
4013     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4014     int err = 0;
4015     switch (hci_stack->state){
4016         case HCI_STATE_OFF:
4017             err = hci_power_control_state_off(power_mode);
4018             break;
4019         case HCI_STATE_INITIALIZING:
4020             err = hci_power_control_state_initializing(power_mode);
4021             break;
4022         case HCI_STATE_WORKING:
4023             err = hci_power_control_state_working(power_mode);
4024             break;
4025         case HCI_STATE_HALTING:
4026             err = hci_power_control_state_halting(power_mode);
4027             break;
4028         case HCI_STATE_FALLING_ASLEEP:
4029             err = hci_power_control_state_falling_asleep(power_mode);
4030             break;
4031         case HCI_STATE_SLEEPING:
4032             err = hci_power_control_state_sleeping(power_mode);
4033             break;
4034         default:
4035             btstack_assert(false);
4036             break;
4037     }
4038     if (err != 0){
4039         return err;
4040     }
4041 
4042     // create internal event
4043 	hci_emit_state();
4044 
4045 	// trigger next/first action
4046 	hci_run();
4047 
4048     return 0;
4049 }
4050 
4051 
4052 #ifdef ENABLE_CLASSIC
4053 
4054 static void hci_update_scan_enable(void){
4055     // 2 = page scan, 1 = inq scan
4056     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4057     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4058     hci_run();
4059 }
4060 
4061 void gap_discoverable_control(uint8_t enable){
4062     if (enable) enable = 1; // normalize argument
4063 
4064     if (hci_stack->discoverable == enable){
4065         hci_emit_discoverable_enabled(hci_stack->discoverable);
4066         return;
4067     }
4068 
4069     hci_stack->discoverable = enable;
4070     hci_update_scan_enable();
4071 }
4072 
4073 void gap_connectable_control(uint8_t enable){
4074     if (enable) enable = 1; // normalize argument
4075 
4076     // don't emit event
4077     if (hci_stack->connectable == enable) return;
4078 
4079     hci_stack->connectable = enable;
4080     hci_update_scan_enable();
4081 }
4082 #endif
4083 
4084 void gap_local_bd_addr(bd_addr_t address_buffer){
4085     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4086 }
4087 
4088 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4089 static void hci_host_num_completed_packets(void){
4090 
4091     // create packet manually as arrays are not supported and num_commands should not get reduced
4092     hci_reserve_packet_buffer();
4093     uint8_t * packet = hci_get_outgoing_packet_buffer();
4094 
4095     uint16_t size = 0;
4096     uint16_t num_handles = 0;
4097     packet[size++] = 0x35;
4098     packet[size++] = 0x0c;
4099     size++;  // skip param len
4100     size++;  // skip num handles
4101 
4102     // add { handle, packets } entries
4103     btstack_linked_item_t * it;
4104     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4105         hci_connection_t * connection = (hci_connection_t *) it;
4106         if (connection->num_packets_completed){
4107             little_endian_store_16(packet, size, connection->con_handle);
4108             size += 2;
4109             little_endian_store_16(packet, size, connection->num_packets_completed);
4110             size += 2;
4111             //
4112             num_handles++;
4113             connection->num_packets_completed = 0;
4114         }
4115     }
4116 
4117     packet[2] = size - 3;
4118     packet[3] = num_handles;
4119 
4120     hci_stack->host_completed_packets = 0;
4121 
4122     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4123     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4124 
4125     // release packet buffer for synchronous transport implementations
4126     if (hci_transport_synchronous()){
4127         hci_release_packet_buffer();
4128         hci_emit_transport_packet_sent();
4129     }
4130 }
4131 #endif
4132 
4133 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4134     UNUSED(ds);
4135     hci_stack->substate = HCI_HALTING_CLOSE;
4136     // allow packet handlers to defer final shutdown
4137     hci_emit_state();
4138     hci_run();
4139 }
4140 
4141 static bool hci_run_acl_fragments(void){
4142     if (hci_stack->acl_fragmentation_total_size > 0u) {
4143         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4144         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4145         if (connection) {
4146             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4147                 hci_send_acl_packet_fragments(connection);
4148                 return true;
4149             }
4150         } else {
4151             // connection gone -> discard further fragments
4152             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4153             hci_stack->acl_fragmentation_total_size = 0;
4154             hci_stack->acl_fragmentation_pos = 0;
4155         }
4156     }
4157     return false;
4158 }
4159 
4160 #ifdef ENABLE_CLASSIC
4161 static bool hci_run_general_gap_classic(void){
4162 
4163     // assert stack is working and classic is active
4164     if (hci_classic_supported() == false)      return false;
4165     if (hci_stack->state != HCI_STATE_WORKING) return false;
4166 
4167     // decline incoming connections
4168     if (hci_stack->decline_reason){
4169         uint8_t reason = hci_stack->decline_reason;
4170         hci_stack->decline_reason = 0;
4171         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4172         return true;
4173     }
4174 
4175     if (hci_stack->gap_tasks != 0){
4176         hci_run_gap_tasks_classic();
4177         return true;
4178     }
4179 
4180     // start/stop inquiry
4181     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4182         uint8_t duration = hci_stack->inquiry_state;
4183         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4184         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4185         return true;
4186     }
4187     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4188         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4189         hci_send_cmd(&hci_inquiry_cancel);
4190         return true;
4191     }
4192     // remote name request
4193     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4194         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4195         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4196                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4197         return true;
4198     }
4199 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4200     // Local OOB data
4201     if (hci_stack->classic_read_local_oob_data){
4202         hci_stack->classic_read_local_oob_data = false;
4203         if (hci_stack->local_supported_commands[1] & 0x10u){
4204             hci_send_cmd(&hci_read_local_extended_oob_data);
4205         } else {
4206             hci_send_cmd(&hci_read_local_oob_data);
4207         }
4208     }
4209 #endif
4210     // pairing
4211     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4212         uint8_t state = hci_stack->gap_pairing_state;
4213         uint8_t pin_code[16];
4214         switch (state){
4215             case GAP_PAIRING_STATE_SEND_PIN:
4216                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4217                 memset(pin_code, 0, 16);
4218                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4219                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4220                 break;
4221             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4222                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4223                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4224                 break;
4225             case GAP_PAIRING_STATE_SEND_PASSKEY:
4226                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4227                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4228                 break;
4229             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4230                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4231                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4232                 break;
4233             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4234                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4235                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4236                 break;
4237             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4238                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4239                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4240                 break;
4241             default:
4242                 break;
4243         }
4244         return true;
4245     }
4246     return false;
4247 }
4248 #endif
4249 
4250 #ifdef ENABLE_BLE
4251 static bool hci_run_general_gap_le(void){
4252 
4253     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4254 
4255     if (hci_stack->state != HCI_STATE_WORKING) return false;
4256     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4257 
4258 
4259     // Phase 1: collect what to stop
4260 
4261     bool scanning_stop = false;
4262     bool connecting_stop = false;
4263     bool advertising_stop = false;
4264 
4265 #ifndef ENABLE_LE_CENTRAL
4266     UNUSED(scanning_stop);
4267     UNUSED(connecting_stop);
4268 #endif
4269 #ifndef ENABLE_LE_PERIPHERAL
4270     UNUSED(advertising_stop);
4271 #endif
4272 
4273     // check if own address changes
4274     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4275 
4276     // check if whitelist needs modification
4277     bool whitelist_modification_pending = false;
4278     btstack_linked_list_iterator_t lit;
4279     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4280     while (btstack_linked_list_iterator_has_next(&lit)){
4281         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4282         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4283             whitelist_modification_pending = true;
4284             break;
4285         }
4286     }
4287     // check if resolving list needs modification
4288     bool resolving_list_modification_pending = false;
4289 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4290     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4291 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4292         resolving_list_modification_pending = true;
4293     }
4294 #endif
4295 
4296 #ifdef ENABLE_LE_CENTRAL
4297     // scanning control
4298     if (hci_stack->le_scanning_active) {
4299         // stop if:
4300         // - parameter change required
4301         // - it's disabled
4302         // - whitelist change required but used for scanning
4303         // - resolving list modified
4304         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4305         if ((hci_stack->le_scanning_param_update) ||
4306             !hci_stack->le_scanning_enabled ||
4307             scanning_uses_whitelist ||
4308             resolving_list_modification_pending){
4309 
4310             scanning_stop = true;
4311         }
4312     }
4313 #endif
4314 
4315 #ifdef ENABLE_LE_CENTRAL
4316     // connecting control
4317     bool connecting_with_whitelist;
4318     switch (hci_stack->le_connecting_state){
4319         case LE_CONNECTING_DIRECT:
4320         case LE_CONNECTING_WHITELIST:
4321             // stop connecting if:
4322             // - connecting uses white and whitelist modification pending
4323             // - if it got disabled
4324             // - resolving list modified
4325             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4326             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4327                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4328                 resolving_list_modification_pending) {
4329 
4330                 connecting_stop = true;
4331             }
4332             break;
4333         default:
4334             break;
4335     }
4336 #endif
4337 
4338 #ifdef ENABLE_LE_PERIPHERAL
4339     // le advertisement control
4340     if (hci_stack->le_advertisements_active){
4341         // stop if:
4342         // - parameter change required
4343         // - random address used in advertising and changes
4344         // - it's disabled
4345         // - whitelist change required but used for advertisement filter policy
4346         // - resolving list modified
4347         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4348         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4349         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4350         if (advertising_change ||
4351             (advertising_uses_random_address && random_address_change) ||
4352             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4353             (advertising_uses_whitelist && whitelist_modification_pending) ||
4354             resolving_list_modification_pending) {
4355 
4356             advertising_stop = true;
4357         }
4358     }
4359 #endif
4360 
4361 
4362     // Phase 2: stop everything that should be off during modifications
4363 
4364 #ifdef ENABLE_LE_CENTRAL
4365     if (scanning_stop){
4366         hci_stack->le_scanning_active = false;
4367         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4368         return true;
4369     }
4370 #endif
4371 
4372 #ifdef ENABLE_LE_CENTRAL
4373     if (connecting_stop){
4374         hci_send_cmd(&hci_le_create_connection_cancel);
4375         return true;
4376     }
4377 #endif
4378 
4379 #ifdef ENABLE_LE_PERIPHERAL
4380     if (advertising_stop){
4381         hci_stack->le_advertisements_active = false;
4382         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4383         return true;
4384     }
4385 #endif
4386 
4387     // Phase 3: modify
4388 
4389     if (random_address_change){
4390         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4391         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4392         return true;
4393     }
4394 
4395 #ifdef ENABLE_LE_CENTRAL
4396     if (hci_stack->le_scanning_param_update){
4397         hci_stack->le_scanning_param_update = false;
4398         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4399                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4400         return true;
4401     }
4402 #endif
4403 
4404 #ifdef ENABLE_LE_PERIPHERAL
4405     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4406         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4407         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4408         hci_send_cmd(&hci_le_set_advertising_parameters,
4409                      hci_stack->le_advertisements_interval_min,
4410                      hci_stack->le_advertisements_interval_max,
4411                      hci_stack->le_advertisements_type,
4412                      hci_stack->le_advertisements_own_addr_type,
4413                      hci_stack->le_advertisements_direct_address_type,
4414                      hci_stack->le_advertisements_direct_address,
4415                      hci_stack->le_advertisements_channel_map,
4416                      hci_stack->le_advertisements_filter_policy);
4417         return true;
4418     }
4419     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4420         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4421         uint8_t adv_data_clean[31];
4422         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4423         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4424                      hci_stack->le_advertisements_data_len);
4425         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4426         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4427         return true;
4428     }
4429     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4430         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4431         uint8_t scan_data_clean[31];
4432         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4433         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4434                      hci_stack->le_scan_response_data_len);
4435         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4436         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4437         return true;
4438     }
4439 #endif
4440 
4441 
4442 #ifdef ENABLE_LE_CENTRAL
4443     // if connect with whitelist was active and is not cancelled yet, wait until next time
4444     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4445 #endif
4446 
4447     // LE Whitelist Management
4448     if (whitelist_modification_pending){
4449         // add/remove entries
4450         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4451         while (btstack_linked_list_iterator_has_next(&lit)){
4452             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4453 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4454 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4455 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4456 				return true;
4457 			}
4458             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4459 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4460                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4461                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4462                 return true;
4463             }
4464             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4465 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4466 				btstack_memory_whitelist_entry_free(entry);
4467             }
4468         }
4469     }
4470 
4471 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4472     // LE Resolving List Management
4473     if (resolving_list_supported) {
4474 		uint16_t i;
4475 		switch (hci_stack->le_resolving_list_state) {
4476 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4477 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4478 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4479 				return true;
4480 			case LE_RESOLVING_LIST_READ_SIZE:
4481 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4482 				hci_send_cmd(&hci_le_read_resolving_list_size);
4483 				return true;
4484 			case LE_RESOLVING_LIST_SEND_CLEAR:
4485 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4486 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4487 							  sizeof(hci_stack->le_resolving_list_add_entries));
4488 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4489 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4490 				hci_send_cmd(&hci_le_clear_resolving_list);
4491 				return true;
4492 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4493 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4494 					uint8_t offset = i >> 3;
4495 					uint8_t mask = 1 << (i & 7);
4496 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4497 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4498 					bd_addr_t peer_identity_addreses;
4499 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4500 					sm_key_t peer_irk;
4501 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4502 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4503 
4504 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4505 					// trigger whitelist entry 'update' (work around for controller bug)
4506 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4507 					while (btstack_linked_list_iterator_has_next(&lit)) {
4508 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4509 						if (entry->address_type != peer_identity_addr_type) continue;
4510 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4511 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4512 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4513 					}
4514 #endif
4515 
4516 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4517 								 peer_identity_addreses);
4518 					return true;
4519 				}
4520 
4521 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4522 
4523 				/* fall through */
4524 
4525 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4526 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4527 					uint8_t offset = i >> 3;
4528 					uint8_t mask = 1 << (i & 7);
4529 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4530 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4531 					bd_addr_t peer_identity_addreses;
4532 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4533 					sm_key_t peer_irk;
4534 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4535 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4536 					const uint8_t *local_irk = gap_get_persistent_irk();
4537 					// command uses format specifier 'P' that stores 16-byte value without flip
4538 					uint8_t local_irk_flipped[16];
4539 					uint8_t peer_irk_flipped[16];
4540 					reverse_128(local_irk, local_irk_flipped);
4541 					reverse_128(peer_irk, peer_irk_flipped);
4542 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4543 								 peer_irk_flipped, local_irk_flipped);
4544 					return true;
4545 				}
4546 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4547 				break;
4548 
4549 			default:
4550 				break;
4551 		}
4552 	}
4553     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4554 #endif
4555 
4556     // Phase 4: restore state
4557 
4558 #ifdef ENABLE_LE_CENTRAL
4559     // re-start scanning
4560     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4561         hci_stack->le_scanning_active = true;
4562         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4563         return true;
4564     }
4565 #endif
4566 
4567 #ifdef ENABLE_LE_CENTRAL
4568     // re-start connecting
4569     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4570         bd_addr_t null_addr;
4571         memset(null_addr, 0, 6);
4572         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4573         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4574         hci_send_cmd(&hci_le_create_connection,
4575                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4576                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4577                      1,         // use whitelist
4578                      0,         // peer address type
4579                      null_addr, // peer bd addr
4580                      hci_stack->le_connection_own_addr_type,   // our addr type:
4581                      hci_stack->le_connection_interval_min,    // conn interval min
4582                      hci_stack->le_connection_interval_max,    // conn interval max
4583                      hci_stack->le_connection_latency,         // conn latency
4584                      hci_stack->le_supervision_timeout,        // conn latency
4585                      hci_stack->le_minimum_ce_length,          // min ce length
4586                      hci_stack->le_maximum_ce_length           // max ce length
4587         );
4588         return true;
4589     }
4590 #endif
4591 
4592 #ifdef ENABLE_LE_PERIPHERAL
4593     // re-start advertising
4594     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4595         // check if advertisements should be enabled given
4596         hci_stack->le_advertisements_active = true;
4597         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4598         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4599         return true;
4600     }
4601 #endif
4602 
4603     return false;
4604 }
4605 #endif
4606 
4607 static bool hci_run_general_pending_commands(void){
4608     btstack_linked_item_t * it;
4609     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4610         hci_connection_t * connection = (hci_connection_t *) it;
4611 
4612         switch(connection->state){
4613             case SEND_CREATE_CONNECTION:
4614                 switch(connection->address_type){
4615 #ifdef ENABLE_CLASSIC
4616                     case BD_ADDR_TYPE_ACL:
4617                         log_info("sending hci_create_connection");
4618                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4619                         break;
4620 #endif
4621                     default:
4622 #ifdef ENABLE_BLE
4623 #ifdef ENABLE_LE_CENTRAL
4624                         log_info("sending hci_le_create_connection");
4625                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4626                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4627                         hci_send_cmd(&hci_le_create_connection,
4628                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4629                                      hci_stack->le_connection_scan_window,      // conn scan windows
4630                                      0,         // don't use whitelist
4631                                      connection->address_type, // peer address type
4632                                      connection->address,      // peer bd addr
4633                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4634                                      hci_stack->le_connection_interval_min,    // conn interval min
4635                                      hci_stack->le_connection_interval_max,    // conn interval max
4636                                      hci_stack->le_connection_latency,         // conn latency
4637                                      hci_stack->le_supervision_timeout,        // conn latency
4638                                      hci_stack->le_minimum_ce_length,          // min ce length
4639                                      hci_stack->le_maximum_ce_length          // max ce length
4640                         );
4641                         connection->state = SENT_CREATE_CONNECTION;
4642 #endif
4643 #endif
4644                         break;
4645                 }
4646                 return true;
4647 
4648 #ifdef ENABLE_CLASSIC
4649             case RECEIVED_CONNECTION_REQUEST:
4650                 connection->role  = HCI_ROLE_SLAVE;
4651                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4652                     log_info("sending hci_accept_connection_request");
4653                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4654                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4655                 }
4656                 return true;
4657 #endif
4658 
4659 #ifdef ENABLE_BLE
4660 #ifdef ENABLE_LE_CENTRAL
4661             case SEND_CANCEL_CONNECTION:
4662                 connection->state = SENT_CANCEL_CONNECTION;
4663                 hci_send_cmd(&hci_le_create_connection_cancel);
4664                 return true;
4665 #endif
4666 #endif
4667             case SEND_DISCONNECT:
4668                 connection->state = SENT_DISCONNECT;
4669                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4670                 return true;
4671 
4672             default:
4673                 break;
4674         }
4675 
4676         // no further commands if connection is about to get shut down
4677         if (connection->state == SENT_DISCONNECT) continue;
4678 
4679         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4680             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4681             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4682             return true;
4683         }
4684 
4685 #ifdef ENABLE_CLASSIC
4686 
4687         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4688             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4689             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4690             return true;
4691         }
4692 
4693         // Handling link key request requires remote supported features
4694         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4695             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4696             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4697 
4698             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4699             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4700             if (have_link_key && security_level_sufficient){
4701                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4702             } else {
4703                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4704             }
4705             return true;
4706         }
4707 
4708         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4709             log_info("denying to pin request");
4710             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4711             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4712             return true;
4713         }
4714 
4715         // security assessment requires remote features
4716         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4717             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4718             hci_ssp_assess_security_on_io_cap_request(connection);
4719             // 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
4720         }
4721 
4722         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4723             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4724             // set authentication requirements:
4725             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4726             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4727             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4728             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4729                 authreq |= 1;
4730             }
4731             bool bonding = hci_stack->bondable;
4732             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4733                 // if we have received IO Cap Response, we're in responder role
4734                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4735                 if (bonding && !remote_bonding){
4736                     log_info("Remote not bonding, dropping local flag");
4737                     bonding = false;
4738                 }
4739             }
4740             if (bonding){
4741                 if (connection->bonding_flags & BONDING_DEDICATED){
4742                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4743                 } else {
4744                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4745                 }
4746             }
4747             uint8_t have_oob_data = 0;
4748 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4749             if (connection->classic_oob_c_192 != NULL){
4750                     have_oob_data |= 1;
4751             }
4752             if (connection->classic_oob_c_256 != NULL){
4753                 have_oob_data |= 2;
4754             }
4755 #endif
4756             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4757             return true;
4758         }
4759 
4760         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4761             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4762             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4763             return true;
4764         }
4765 
4766 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4767         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4768             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4769             const uint8_t zero[16] = { 0 };
4770             const uint8_t * r_192 = zero;
4771             const uint8_t * c_192 = zero;
4772             const uint8_t * r_256 = zero;
4773             const uint8_t * c_256 = zero;
4774             // verify P-256 OOB
4775             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4776                 c_256 = connection->classic_oob_c_256;
4777                 if (connection->classic_oob_r_256 != NULL) {
4778                     r_256 = connection->classic_oob_r_256;
4779                 }
4780             }
4781             // verify P-192 OOB
4782             if ((connection->classic_oob_c_192 != NULL)) {
4783                 c_192 = connection->classic_oob_c_192;
4784                 if (connection->classic_oob_r_192 != NULL) {
4785                     r_192 = connection->classic_oob_r_192;
4786                 }
4787             }
4788 
4789             // assess security
4790             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4791             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4792             if (need_level_4 && !can_reach_level_4){
4793                 log_info("Level 4 required, but not possible -> abort");
4794                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4795                 // send oob negative reply
4796                 c_256 = NULL;
4797                 c_192 = NULL;
4798             }
4799 
4800             // Reply
4801             if (c_256 != zero) {
4802                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4803             } else if (c_192 != zero){
4804                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4805             } else {
4806                 hci_stack->classic_oob_con_handle = connection->con_handle;
4807                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4808             }
4809             return true;
4810         }
4811 #endif
4812 
4813         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4814             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4815             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4816             return true;
4817         }
4818 
4819         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4820             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4821             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4822             return true;
4823         }
4824 
4825         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4826             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4827             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4828             return true;
4829         }
4830 
4831         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4832             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4833             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4834             connection->state = SENT_DISCONNECT;
4835             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4836             return true;
4837         }
4838 
4839         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4840             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4841             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4842             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4843             return true;
4844         }
4845 
4846         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4847             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4848             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4849             return true;
4850         }
4851 
4852         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4853             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4854             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4855             return true;
4856         }
4857 
4858         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4859             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4860             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4861             return true;
4862         }
4863 
4864         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4865             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4866             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4867             return true;
4868         }
4869 
4870         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4871             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4872             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4873             return true;
4874         }
4875 #endif
4876 
4877         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4878             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4879 #ifdef ENABLE_CLASSIC
4880             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4881 #endif
4882             if (connection->state != SENT_DISCONNECT){
4883                 connection->state = SENT_DISCONNECT;
4884                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4885                 return true;
4886             }
4887         }
4888 
4889 #ifdef ENABLE_CLASSIC
4890         uint16_t sniff_min_interval;
4891         switch (connection->sniff_min_interval){
4892             case 0:
4893                 break;
4894             case 0xffff:
4895                 connection->sniff_min_interval = 0;
4896                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4897                 return true;
4898             default:
4899                 sniff_min_interval = connection->sniff_min_interval;
4900                 connection->sniff_min_interval = 0;
4901                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4902                 return true;
4903         }
4904 
4905         if (connection->sniff_subrating_max_latency != 0xffff){
4906             uint16_t max_latency = connection->sniff_subrating_max_latency;
4907             connection->sniff_subrating_max_latency = 0;
4908             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4909             return true;
4910         }
4911 
4912         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4913             uint8_t service_type = (uint8_t) connection->qos_service_type;
4914             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4915             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);
4916             return true;
4917         }
4918 
4919         if (connection->request_role != HCI_ROLE_INVALID){
4920             hci_role_t role = connection->request_role;
4921             connection->request_role = HCI_ROLE_INVALID;
4922             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4923             return true;
4924         }
4925 #endif
4926 
4927 #ifdef ENABLE_BLE
4928         switch (connection->le_con_parameter_update_state){
4929             // response to L2CAP CON PARAMETER UPDATE REQUEST
4930             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4931                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4932                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4933                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4934                              0x0000, 0xffff);
4935                 return true;
4936             case CON_PARAMETER_UPDATE_REPLY:
4937                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4938                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4939                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4940                              0x0000, 0xffff);
4941                 return true;
4942             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4943                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4944                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4945                 return true;
4946             default:
4947                 break;
4948         }
4949         if (connection->le_phy_update_all_phys != 0xffu){
4950             uint8_t all_phys = connection->le_phy_update_all_phys;
4951             connection->le_phy_update_all_phys = 0xff;
4952             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);
4953             return true;
4954         }
4955 #endif
4956     }
4957     return false;
4958 }
4959 
4960 static void hci_run(void){
4961 
4962     bool done;
4963 
4964     // send continuation fragments first, as they block the prepared packet buffer
4965     done = hci_run_acl_fragments();
4966     if (done) return;
4967 
4968 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4969     // send host num completed packets next as they don't require num_cmd_packets > 0
4970     if (!hci_can_send_comand_packet_transport()) return;
4971     if (hci_stack->host_completed_packets){
4972         hci_host_num_completed_packets();
4973         return;
4974     }
4975 #endif
4976 
4977     if (!hci_can_send_command_packet_now()) return;
4978 
4979     // global/non-connection oriented commands
4980 
4981 
4982 #ifdef ENABLE_CLASSIC
4983     // general gap classic
4984     done = hci_run_general_gap_classic();
4985     if (done) return;
4986 #endif
4987 
4988 #ifdef ENABLE_BLE
4989     // general gap le
4990     done = hci_run_general_gap_le();
4991     if (done) return;
4992 #endif
4993 
4994     // send pending HCI commands
4995     done = hci_run_general_pending_commands();
4996     if (done) return;
4997 
4998     // stack state sub statemachines
4999     hci_connection_t * connection;
5000     switch (hci_stack->state){
5001         case HCI_STATE_INITIALIZING:
5002             hci_initializing_run();
5003             break;
5004 
5005         case HCI_STATE_HALTING:
5006 
5007             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5008             switch (hci_stack->substate){
5009                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5010                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5011 
5012 #ifdef ENABLE_BLE
5013 #ifdef ENABLE_LE_CENTRAL
5014                     hci_whitelist_free();
5015 #endif
5016 #endif
5017                     // close all open connections
5018                     connection =  (hci_connection_t *) hci_stack->connections;
5019                     if (connection){
5020                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5021                         if (!hci_can_send_command_packet_now()) return;
5022 
5023                         // check state
5024                         if (connection->state == SENT_DISCONNECT) return;
5025                         connection->state = SENT_DISCONNECT;
5026 
5027                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5028 
5029                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5030                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5031 
5032                         // ... which would be ignored anyway as we shutdown (free) the connection now
5033                         hci_shutdown_connection(connection);
5034 
5035                         // finally, send the disconnect command
5036                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5037                         return;
5038                     }
5039 
5040                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5041                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5042                         log_info("HCI_STATE_HALTING: wait 50 ms");
5043                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5044                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5045                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5046                         btstack_run_loop_add_timer(&hci_stack->timeout);
5047                         break;
5048                     }
5049 
5050                     /* fall through */
5051 
5052                 case HCI_HALTING_CLOSE:
5053                     log_info("HCI_STATE_HALTING, calling off");
5054 
5055                     // switch mode
5056                     hci_power_control_off();
5057 
5058                     log_info("HCI_STATE_HALTING, emitting state");
5059                     hci_emit_state();
5060                     log_info("HCI_STATE_HALTING, done");
5061                     break;
5062 
5063                 case HCI_HALTING_W4_TIMER:
5064                     // keep waiting
5065 
5066                     break;
5067                 default:
5068                     break;
5069             }
5070 
5071             break;
5072 
5073         case HCI_STATE_FALLING_ASLEEP:
5074             switch(hci_stack->substate) {
5075                 case HCI_FALLING_ASLEEP_DISCONNECT:
5076                     log_info("HCI_STATE_FALLING_ASLEEP");
5077                     // close all open connections
5078                     connection =  (hci_connection_t *) hci_stack->connections;
5079                     if (connection){
5080 
5081                         // send disconnect
5082                         if (!hci_can_send_command_packet_now()) return;
5083 
5084                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5085                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5086 
5087                         // send disconnected event right away - causes higher layer connections to get closed, too.
5088                         hci_shutdown_connection(connection);
5089                         return;
5090                     }
5091 
5092                     if (hci_classic_supported()){
5093                         // disable page and inquiry scan
5094                         if (!hci_can_send_command_packet_now()) return;
5095 
5096                         log_info("HCI_STATE_HALTING, disabling inq scans");
5097                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5098 
5099                         // continue in next sub state
5100                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5101                         break;
5102                     }
5103 
5104                     /* fall through */
5105 
5106                 case HCI_FALLING_ASLEEP_COMPLETE:
5107                     log_info("HCI_STATE_HALTING, calling sleep");
5108                     // switch mode
5109                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5110                     hci_emit_state();
5111                     break;
5112 
5113                 default:
5114                     break;
5115             }
5116             break;
5117 
5118         default:
5119             break;
5120     }
5121 }
5122 
5123 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5124     // house-keeping
5125 
5126 #ifdef ENABLE_CLASSIC
5127     bd_addr_t addr;
5128     hci_connection_t * conn;
5129 #endif
5130 #ifdef ENABLE_LE_CENTRAL
5131     uint8_t initiator_filter_policy;
5132 #endif
5133 
5134     uint16_t opcode = little_endian_read_16(packet, 0);
5135     switch (opcode) {
5136         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5137             hci_stack->loopback_mode = packet[3];
5138             break;
5139 
5140 #ifdef ENABLE_CLASSIC
5141         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5142             reverse_bd_addr(&packet[3], addr);
5143             log_info("Create_connection to %s", bd_addr_to_str(addr));
5144 
5145             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5146             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5147                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5148                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5149             }
5150 
5151             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5152             if (!conn) {
5153                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5154                 if (!conn) {
5155                     // notify client that alloc failed
5156                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5157                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5158                 }
5159                 conn->state = SEND_CREATE_CONNECTION;
5160                 conn->role  = HCI_ROLE_MASTER;
5161             }
5162 
5163             conn->con_handle = HCI_CON_HANDLE_INVALID;
5164             conn->role = HCI_ROLE_INVALID;
5165 
5166             log_info("conn state %u", conn->state);
5167             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5168             switch (conn->state) {
5169                 // if connection active exists
5170                 case OPEN:
5171                     // and OPEN, emit connection complete command
5172                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5173                     // packet not sent to controller
5174                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5175                 case RECEIVED_DISCONNECTION_COMPLETE:
5176                     // create connection triggered in disconnect complete event, let's do it now
5177                     break;
5178                 case SEND_CREATE_CONNECTION:
5179                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5180                     break;
5181                 default:
5182                     // otherwise, just ignore as it is already in the open process
5183                     // packet not sent to controller
5184                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5185             }
5186             conn->state = SENT_CREATE_CONNECTION;
5187 
5188             // track outgoing connection
5189             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5190             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5191             break;
5192 
5193 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5194         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5195             // setup_synchronous_connection? Voice setting at offset 22
5196             // TODO: compare to current setting if sco connection already active
5197             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5198             break;
5199         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5200             // accept_synchronous_connection? Voice setting at offset 18
5201             // TODO: compare to current setting if sco connection already active
5202             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5203             break;
5204 #endif
5205 #endif
5206 
5207 #ifdef ENABLE_BLE
5208 #ifdef ENABLE_LE_CENTRAL
5209         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5210             // white list used?
5211             initiator_filter_policy = packet[7];
5212             switch (initiator_filter_policy) {
5213                 case 0:
5214                     // whitelist not used
5215                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5216                     break;
5217                 case 1:
5218                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5219                     break;
5220                 default:
5221                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5222                     break;
5223             }
5224             // track outgoing connection
5225             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5226             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5227             break;
5228         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5229             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5230             break;
5231 #endif
5232 #endif
5233         default:
5234             break;
5235     }
5236 
5237     hci_stack->num_cmd_packets--;
5238 
5239     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5240     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5241     if (err != 0){
5242         return ERROR_CODE_HARDWARE_FAILURE;
5243     }
5244     return ERROR_CODE_SUCCESS;
5245 }
5246 
5247 // disconnect because of security block
5248 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5249     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5250     if (!connection) return;
5251     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5252 }
5253 
5254 
5255 // Configure Secure Simple Pairing
5256 
5257 #ifdef ENABLE_CLASSIC
5258 
5259 // enable will enable SSP during init
5260 void gap_ssp_set_enable(int enable){
5261     hci_stack->ssp_enable = enable;
5262 }
5263 
5264 static int hci_local_ssp_activated(void){
5265     return gap_ssp_supported() && hci_stack->ssp_enable;
5266 }
5267 
5268 // if set, BTstack will respond to io capability request using authentication requirement
5269 void gap_ssp_set_io_capability(int io_capability){
5270     hci_stack->ssp_io_capability = io_capability;
5271 }
5272 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5273     hci_stack->ssp_authentication_requirement = authentication_requirement;
5274 }
5275 
5276 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5277 void gap_ssp_set_auto_accept(int auto_accept){
5278     hci_stack->ssp_auto_accept = auto_accept;
5279 }
5280 
5281 void gap_secure_connections_enable(bool enable){
5282     hci_stack->secure_connections_enable = enable;
5283 }
5284 
5285 #endif
5286 
5287 // va_list part of hci_send_cmd
5288 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5289     if (!hci_can_send_command_packet_now()){
5290         log_error("hci_send_cmd called but cannot send packet now");
5291         return ERROR_CODE_COMMAND_DISALLOWED;
5292     }
5293 
5294     // for HCI INITIALIZATION
5295     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5296     hci_stack->last_cmd_opcode = cmd->opcode;
5297 
5298     hci_reserve_packet_buffer();
5299     uint8_t * packet = hci_stack->hci_packet_buffer;
5300     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5301     uint8_t status = hci_send_cmd_packet(packet, size);
5302 
5303     // release packet buffer on error or for synchronous transport implementations
5304     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5305         hci_release_packet_buffer();
5306         hci_emit_transport_packet_sent();
5307     }
5308 
5309     return status;
5310 }
5311 
5312 /**
5313  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5314  */
5315 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5316     va_list argptr;
5317     va_start(argptr, cmd);
5318     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5319     va_end(argptr);
5320     return status;
5321 }
5322 
5323 // Create various non-HCI events.
5324 // TODO: generalize, use table similar to hci_create_command
5325 
5326 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5327     // dump packet
5328     if (dump) {
5329         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5330     }
5331 
5332     // dispatch to all event handlers
5333     btstack_linked_list_iterator_t it;
5334     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5335     while (btstack_linked_list_iterator_has_next(&it)){
5336         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5337         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5338     }
5339 }
5340 
5341 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5342     if (!hci_stack->acl_packet_handler) return;
5343     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5344 }
5345 
5346 #ifdef ENABLE_CLASSIC
5347 static void hci_notify_if_sco_can_send_now(void){
5348     // notify SCO sender if waiting
5349     if (!hci_stack->sco_waiting_for_can_send_now) return;
5350     if (hci_can_send_sco_packet_now()){
5351         hci_stack->sco_waiting_for_can_send_now = 0;
5352         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5353         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5354         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5355     }
5356 }
5357 
5358 // parsing end emitting has been merged to reduce code size
5359 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5360     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5361 
5362     uint8_t * eir_data;
5363     ad_context_t context;
5364     const uint8_t * name;
5365     uint8_t         name_len;
5366 
5367     if (size < 3) return;
5368 
5369     int event_type = hci_event_packet_get_type(packet);
5370     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5371     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5372 
5373     switch (event_type){
5374         case HCI_EVENT_INQUIRY_RESULT:
5375         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5376             if (size != (3 + (num_responses * 14))) return;
5377             break;
5378         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5379             if (size != 257) return;
5380             if (num_responses != 1) return;
5381             break;
5382         default:
5383             return;
5384     }
5385 
5386     // event[1] is set at the end
5387     int i;
5388     for (i=0; i<num_responses;i++){
5389         memset(event, 0, sizeof(event));
5390         event[0] = GAP_EVENT_INQUIRY_RESULT;
5391         uint8_t event_size = 27;    // if name is not set by EIR
5392 
5393         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5394         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5395         (void)memcpy(&event[9],
5396                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5397                      3); // class of device
5398         (void)memcpy(&event[12],
5399                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5400                      2); // clock offset
5401 
5402         switch (event_type){
5403             case HCI_EVENT_INQUIRY_RESULT:
5404                 // 14,15,16,17 = 0, size 18
5405                 break;
5406             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5407                 event[14] = 1;
5408                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5409                 // 16,17 = 0, size 18
5410                 break;
5411             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5412                 event[14] = 1;
5413                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5414                 // EIR packets only contain a single inquiry response
5415                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5416                 name = NULL;
5417                 // Iterate over EIR data
5418                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5419                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5420                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5421                     const uint8_t * data = ad_iterator_get_data(&context);
5422                     // Prefer Complete Local Name over Shortened Local Name
5423                     switch (data_type){
5424                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5425                             if (name) continue;
5426                             /* fall through */
5427                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5428                             name = data;
5429                             name_len = data_size;
5430                             break;
5431                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5432                             if (data_size != 8) break;
5433                             event[16] = 1;
5434                             memcpy(&event[17], data, 8);
5435                             break;
5436                         default:
5437                             break;
5438                     }
5439                 }
5440                 if (name){
5441                     event[25] = 1;
5442                     // truncate name if needed
5443                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5444                     event[26] = len;
5445                     (void)memcpy(&event[27], name, len);
5446                     event_size += len;
5447                 }
5448                 break;
5449             default:
5450                 return;
5451         }
5452         event[1] = event_size - 2;
5453         hci_emit_event(event, event_size, 1);
5454     }
5455 }
5456 #endif
5457 
5458 void hci_emit_state(void){
5459     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5460     uint8_t event[3];
5461     event[0] = BTSTACK_EVENT_STATE;
5462     event[1] = sizeof(event) - 2u;
5463     event[2] = hci_stack->state;
5464     hci_emit_event(event, sizeof(event), 1);
5465 }
5466 
5467 #ifdef ENABLE_CLASSIC
5468 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5469     uint8_t event[13];
5470     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5471     event[1] = sizeof(event) - 2;
5472     event[2] = status;
5473     little_endian_store_16(event, 3, con_handle);
5474     reverse_bd_addr(address, &event[5]);
5475     event[11] = 1; // ACL connection
5476     event[12] = 0; // encryption disabled
5477     hci_emit_event(event, sizeof(event), 1);
5478 }
5479 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5480     if (disable_l2cap_timeouts) return;
5481     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5482     uint8_t event[4];
5483     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5484     event[1] = sizeof(event) - 2;
5485     little_endian_store_16(event, 2, conn->con_handle);
5486     hci_emit_event(event, sizeof(event), 1);
5487 }
5488 #endif
5489 
5490 #ifdef ENABLE_BLE
5491 #ifdef ENABLE_LE_CENTRAL
5492 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){
5493     uint8_t event[21];
5494     event[0] = HCI_EVENT_LE_META;
5495     event[1] = sizeof(event) - 2u;
5496     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5497     event[3] = status;
5498     little_endian_store_16(event, 4, con_handle);
5499     event[6] = 0; // TODO: role
5500     event[7] = address_type;
5501     reverse_bd_addr(address, &event[8]);
5502     little_endian_store_16(event, 14, 0); // interval
5503     little_endian_store_16(event, 16, 0); // latency
5504     little_endian_store_16(event, 18, 0); // supervision timeout
5505     event[20] = 0; // master clock accuracy
5506     hci_emit_event(event, sizeof(event), 1);
5507 }
5508 #endif
5509 #endif
5510 
5511 static void hci_emit_transport_packet_sent(void){
5512     // notify upper stack that it might be possible to send again
5513     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5514     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5515 }
5516 
5517 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5518     uint8_t event[6];
5519     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5520     event[1] = sizeof(event) - 2u;
5521     event[2] = 0; // status = OK
5522     little_endian_store_16(event, 3, con_handle);
5523     event[5] = reason;
5524     hci_emit_event(event, sizeof(event), 1);
5525 }
5526 
5527 static void hci_emit_nr_connections_changed(void){
5528     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5529     uint8_t event[3];
5530     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5531     event[1] = sizeof(event) - 2u;
5532     event[2] = nr_hci_connections();
5533     hci_emit_event(event, sizeof(event), 1);
5534 }
5535 
5536 static void hci_emit_hci_open_failed(void){
5537     log_info("BTSTACK_EVENT_POWERON_FAILED");
5538     uint8_t event[2];
5539     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5540     event[1] = sizeof(event) - 2u;
5541     hci_emit_event(event, sizeof(event), 1);
5542 }
5543 
5544 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5545     log_info("hci_emit_dedicated_bonding_result %u ", status);
5546     uint8_t event[9];
5547     int pos = 0;
5548     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5549     event[pos++] = sizeof(event) - 2u;
5550     event[pos++] = status;
5551     reverse_bd_addr(address, &event[pos]);
5552     hci_emit_event(event, sizeof(event), 1);
5553 }
5554 
5555 
5556 #ifdef ENABLE_CLASSIC
5557 
5558 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5559     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5560     uint8_t event[5];
5561     int pos = 0;
5562     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5563     event[pos++] = sizeof(event) - 2;
5564     little_endian_store_16(event, 2, con_handle);
5565     pos += 2;
5566     event[pos++] = level;
5567     hci_emit_event(event, sizeof(event), 1);
5568 }
5569 
5570 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5571     if (!connection) return LEVEL_0;
5572     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5573     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5574     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5575     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5576     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5577     // LEVEL 4 always requires 128 bit encrytion key size
5578     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5579         security_level = LEVEL_3;
5580     }
5581     return security_level;
5582 }
5583 
5584 static void hci_emit_discoverable_enabled(uint8_t enabled){
5585     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5586     uint8_t event[3];
5587     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5588     event[1] = sizeof(event) - 2;
5589     event[2] = enabled;
5590     hci_emit_event(event, sizeof(event), 1);
5591 }
5592 
5593 // query if remote side supports eSCO
5594 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5595     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5596     if (!connection) return false;
5597     return (connection->remote_supported_features[0] & 1) != 0;
5598 }
5599 
5600 static bool hci_ssp_supported(hci_connection_t * connection){
5601     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5602     return (connection->bonding_flags & mask) == mask;
5603 }
5604 
5605 // query if remote side supports SSP
5606 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5607     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5608     if (!connection) return false;
5609     return hci_ssp_supported(connection) ? 1 : 0;
5610 }
5611 
5612 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5613     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5614 }
5615 
5616 /**
5617  * Check if remote supported features query has completed
5618  */
5619 bool hci_remote_features_available(hci_con_handle_t handle){
5620     hci_connection_t * connection = hci_connection_for_handle(handle);
5621     if (!connection) return false;
5622     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5623 }
5624 
5625 /**
5626  * Trigger remote supported features query
5627  */
5628 
5629 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection){
5630     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) == 0){
5631         connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5632     }
5633 }
5634 
5635 void hci_remote_features_query(hci_con_handle_t con_handle){
5636     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5637     if (!connection) return;
5638     hci_trigger_remote_features_for_connection(connection);
5639     hci_run();
5640 }
5641 
5642 // GAP API
5643 /**
5644  * @bbrief enable/disable bonding. default is enabled
5645  * @praram enabled
5646  */
5647 void gap_set_bondable_mode(int enable){
5648     hci_stack->bondable = enable ? 1 : 0;
5649 }
5650 /**
5651  * @brief Get bondable mode.
5652  * @return 1 if bondable
5653  */
5654 int gap_get_bondable_mode(void){
5655     return hci_stack->bondable;
5656 }
5657 
5658 /**
5659  * @brief map link keys to security levels
5660  */
5661 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5662     switch (link_key_type){
5663         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5664             return LEVEL_4;
5665         case COMBINATION_KEY:
5666         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5667             return LEVEL_3;
5668         default:
5669             return LEVEL_2;
5670     }
5671 }
5672 
5673 /**
5674  * @brief map link keys to secure connection yes/no
5675  */
5676 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5677     switch (link_key_type){
5678         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5679         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5680             return 1;
5681         default:
5682             return 0;
5683     }
5684 }
5685 
5686 /**
5687  * @brief map link keys to authenticated
5688  */
5689 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5690     switch (link_key_type){
5691         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5692         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5693             return 1;
5694         default:
5695             return 0;
5696     }
5697 }
5698 
5699 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5700     log_info("gap_mitm_protection_required_for_security_level %u", level);
5701     return level > LEVEL_2;
5702 }
5703 
5704 /**
5705  * @brief get current security level
5706  */
5707 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5708     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5709     if (!connection) return LEVEL_0;
5710     return gap_security_level_for_connection(connection);
5711 }
5712 
5713 /**
5714  * @brief request connection to device to
5715  * @result GAP_AUTHENTICATION_RESULT
5716  */
5717 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5718     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5719     if (!connection){
5720         hci_emit_security_level(con_handle, LEVEL_0);
5721         return;
5722     }
5723 
5724     btstack_assert(hci_is_le_connection(connection) == false);
5725 
5726     // 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)
5727     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5728     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5729         requested_level = LEVEL_4;
5730     }
5731 
5732     gap_security_level_t current_level = gap_security_level(con_handle);
5733     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5734         requested_level, connection->requested_security_level, current_level);
5735 
5736     // authentication active if authentication request was sent or planned level > 0
5737     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5738     if (authentication_active){
5739         // authentication already active
5740         if (connection->requested_security_level < requested_level){
5741             // increase requested level as new level is higher
5742             // TODO: handle re-authentication when done
5743             connection->requested_security_level = requested_level;
5744         }
5745     } else {
5746         // no request active, notify if security sufficient
5747         if (requested_level <= current_level){
5748             hci_emit_security_level(con_handle, current_level);
5749             return;
5750         }
5751 
5752         // store request
5753         connection->requested_security_level = requested_level;
5754 
5755         // request remote features if not already active
5756         hci_remote_features_query(con_handle);
5757 
5758         // start to authenticate connection
5759         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5760         hci_run();
5761     }
5762 }
5763 
5764 /**
5765  * @brief start dedicated bonding with device. disconnect after bonding
5766  * @param device
5767  * @param request MITM protection
5768  * @result GAP_DEDICATED_BONDING_COMPLETE
5769  */
5770 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5771 
5772     // create connection state machine
5773     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5774 
5775     if (!connection){
5776         return BTSTACK_MEMORY_ALLOC_FAILED;
5777     }
5778 
5779     // delete linkn key
5780     gap_drop_link_key_for_bd_addr(device);
5781 
5782     // configure LEVEL_2/3, dedicated bonding
5783     connection->state = SEND_CREATE_CONNECTION;
5784     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5785     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5786     connection->bonding_flags = BONDING_DEDICATED;
5787 
5788     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5789 
5790     // handle: connnection failure (connection complete != ok)
5791     // handle: authentication failure
5792     // handle: disconnect on done
5793 
5794     hci_run();
5795 
5796     return 0;
5797 }
5798 
5799 void gap_set_local_name(const char * local_name){
5800     hci_stack->local_name = local_name;
5801     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5802     // also update EIR if not set by user
5803     if (hci_stack->eir_data == NULL){
5804         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5805     }
5806     hci_run();
5807 }
5808 #endif
5809 
5810 
5811 #ifdef ENABLE_BLE
5812 
5813 #ifdef ENABLE_LE_CENTRAL
5814 void gap_start_scan(void){
5815     hci_stack->le_scanning_enabled = true;
5816     hci_run();
5817 }
5818 
5819 void gap_stop_scan(void){
5820     hci_stack->le_scanning_enabled = false;
5821     hci_run();
5822 }
5823 
5824 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5825     hci_stack->le_scan_type          = scan_type;
5826     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5827     hci_stack->le_scan_interval      = scan_interval;
5828     hci_stack->le_scan_window        = scan_window;
5829     hci_stack->le_scanning_param_update = true;
5830     hci_run();
5831 }
5832 
5833 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5834     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5835 }
5836 
5837 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5838     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5839     if (!conn){
5840         // disallow if le connection is already outgoing
5841         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5842             log_error("le connection already active");
5843             return ERROR_CODE_COMMAND_DISALLOWED;
5844         }
5845 
5846         log_info("gap_connect: no connection exists yet, creating context");
5847         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5848         if (!conn){
5849             // notify client that alloc failed
5850             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5851             log_info("gap_connect: failed to alloc hci_connection_t");
5852             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5853         }
5854 
5855         // set le connecting state
5856         if (hci_is_le_connection_type(addr_type)){
5857             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5858         }
5859 
5860         conn->state = SEND_CREATE_CONNECTION;
5861         log_info("gap_connect: send create connection next");
5862         hci_run();
5863         return ERROR_CODE_SUCCESS;
5864     }
5865 
5866     if (!hci_is_le_connection(conn) ||
5867         (conn->state == SEND_CREATE_CONNECTION) ||
5868         (conn->state == SENT_CREATE_CONNECTION)) {
5869         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5870         log_error("gap_connect: classic connection or connect is already being created");
5871         return GATT_CLIENT_IN_WRONG_STATE;
5872     }
5873 
5874     // check if connection was just disconnected
5875     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5876         log_info("gap_connect: send create connection (again)");
5877         conn->state = SEND_CREATE_CONNECTION;
5878         hci_run();
5879         return ERROR_CODE_SUCCESS;
5880     }
5881 
5882     log_info("gap_connect: context exists with state %u", conn->state);
5883     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5884     hci_run();
5885     return ERROR_CODE_SUCCESS;
5886 }
5887 
5888 // @assumption: only a single outgoing LE Connection exists
5889 static hci_connection_t * gap_get_outgoing_connection(void){
5890     btstack_linked_item_t *it;
5891     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5892         hci_connection_t * conn = (hci_connection_t *) it;
5893         if (!hci_is_le_connection(conn)) continue;
5894         switch (conn->state){
5895             case SEND_CREATE_CONNECTION:
5896             case SENT_CREATE_CONNECTION:
5897             case SENT_CANCEL_CONNECTION:
5898                 return conn;
5899             default:
5900                 break;
5901         };
5902     }
5903     return NULL;
5904 }
5905 
5906 uint8_t gap_connect_cancel(void){
5907     hci_connection_t * conn = gap_get_outgoing_connection();
5908     if (!conn) return 0;
5909     switch (conn->state){
5910         case SEND_CREATE_CONNECTION:
5911             // skip sending create connection and emit event instead
5912             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5913             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5914             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5915             btstack_memory_hci_connection_free( conn );
5916             break;
5917         case SENT_CREATE_CONNECTION:
5918             // request to send cancel connection
5919             conn->state = SEND_CANCEL_CONNECTION;
5920             hci_run();
5921             break;
5922         default:
5923             break;
5924     }
5925     return 0;
5926 }
5927 #endif
5928 
5929 #ifdef ENABLE_LE_CENTRAL
5930 /**
5931  * @brief Set connection parameters for outgoing connections
5932  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5933  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5934  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5935  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5936  * @param conn_latency, default: 4
5937  * @param supervision_timeout (unit: 10ms), default: 720 ms
5938  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5939  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5940  */
5941 
5942 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5943     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5944     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5945     hci_stack->le_connection_scan_interval = conn_scan_interval;
5946     hci_stack->le_connection_scan_window = conn_scan_window;
5947     hci_stack->le_connection_interval_min = conn_interval_min;
5948     hci_stack->le_connection_interval_max = conn_interval_max;
5949     hci_stack->le_connection_latency = conn_latency;
5950     hci_stack->le_supervision_timeout = supervision_timeout;
5951     hci_stack->le_minimum_ce_length = min_ce_length;
5952     hci_stack->le_maximum_ce_length = max_ce_length;
5953 }
5954 #endif
5955 
5956 /**
5957  * @brief Updates the connection parameters for a given LE connection
5958  * @param handle
5959  * @param conn_interval_min (unit: 1.25ms)
5960  * @param conn_interval_max (unit: 1.25ms)
5961  * @param conn_latency
5962  * @param supervision_timeout (unit: 10ms)
5963  * @return 0 if ok
5964  */
5965 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5966     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5967     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5968     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5969     connection->le_conn_interval_min = conn_interval_min;
5970     connection->le_conn_interval_max = conn_interval_max;
5971     connection->le_conn_latency = conn_latency;
5972     connection->le_supervision_timeout = supervision_timeout;
5973     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5974     hci_run();
5975     return 0;
5976 }
5977 
5978 /**
5979  * @brief Request an update of the connection parameter 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_request_connection_parameter_update(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_SEND_REQUEST;
5996     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5997     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5998     return 0;
5999 }
6000 
6001 #ifdef ENABLE_LE_PERIPHERAL
6002 
6003 /**
6004  * @brief Set Advertisement Data
6005  * @param advertising_data_length
6006  * @param advertising_data (max 31 octets)
6007  * @note data is not copied, pointer has to stay valid
6008  */
6009 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6010     hci_stack->le_advertisements_data_len = advertising_data_length;
6011     hci_stack->le_advertisements_data = advertising_data;
6012     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6013     hci_run();
6014 }
6015 
6016 /**
6017  * @brief Set Scan Response Data
6018  * @param advertising_data_length
6019  * @param advertising_data (max 31 octets)
6020  * @note data is not copied, pointer has to stay valid
6021  */
6022 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6023     hci_stack->le_scan_response_data_len = scan_response_data_length;
6024     hci_stack->le_scan_response_data = scan_response_data;
6025     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6026     hci_run();
6027 }
6028 
6029 /**
6030  * @brief Set Advertisement Parameters
6031  * @param adv_int_min
6032  * @param adv_int_max
6033  * @param adv_type
6034  * @param direct_address_type
6035  * @param direct_address
6036  * @param channel_map
6037  * @param filter_policy
6038  *
6039  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6040  */
6041  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6042     uint8_t direct_address_typ, bd_addr_t direct_address,
6043     uint8_t channel_map, uint8_t filter_policy) {
6044 
6045     hci_stack->le_advertisements_interval_min = adv_int_min;
6046     hci_stack->le_advertisements_interval_max = adv_int_max;
6047     hci_stack->le_advertisements_type = adv_type;
6048     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6049     hci_stack->le_advertisements_channel_map = channel_map;
6050     hci_stack->le_advertisements_filter_policy = filter_policy;
6051     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6052                  6);
6053 
6054     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6055     hci_run();
6056  }
6057 
6058 /**
6059  * @brief Enable/Disable Advertisements
6060  * @param enabled
6061  */
6062 void gap_advertisements_enable(int enabled){
6063     hci_stack->le_advertisements_enabled = enabled != 0;
6064     hci_update_advertisements_enabled_for_current_roles();
6065     hci_run();
6066 }
6067 
6068 #endif
6069 
6070 void hci_le_set_own_address_type(uint8_t own_address_type){
6071     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6072     if (own_address_type == hci_stack->le_own_addr_type) return;
6073     hci_stack->le_own_addr_type = own_address_type;
6074 
6075 #ifdef ENABLE_LE_PERIPHERAL
6076     // update advertisement parameters, too
6077     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6078     hci_run();
6079 #endif
6080 #ifdef ENABLE_LE_CENTRAL
6081     // note: we don't update scan parameters or modify ongoing connection attempts
6082 #endif
6083 }
6084 
6085 void hci_le_random_address_set(const bd_addr_t random_address){
6086     memcpy(hci_stack->le_random_address, random_address, 6);
6087     hci_stack->le_random_address_set = true;
6088     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6089     hci_run();
6090 }
6091 
6092 #endif
6093 
6094 uint8_t gap_disconnect(hci_con_handle_t handle){
6095     hci_connection_t * conn = hci_connection_for_handle(handle);
6096     if (!conn){
6097         hci_emit_disconnection_complete(handle, 0);
6098         return 0;
6099     }
6100     // ignore if already disconnected
6101     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6102         return 0;
6103     }
6104     conn->state = SEND_DISCONNECT;
6105     hci_run();
6106     return 0;
6107 }
6108 
6109 int gap_read_rssi(hci_con_handle_t con_handle){
6110     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6111     if (hci_connection == NULL) return 0;
6112     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6113     hci_run();
6114     return 1;
6115 }
6116 
6117 /**
6118  * @brief Get connection type
6119  * @param con_handle
6120  * @result connection_type
6121  */
6122 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6123     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6124     if (!conn) return GAP_CONNECTION_INVALID;
6125     switch (conn->address_type){
6126         case BD_ADDR_TYPE_LE_PUBLIC:
6127         case BD_ADDR_TYPE_LE_RANDOM:
6128             return GAP_CONNECTION_LE;
6129         case BD_ADDR_TYPE_SCO:
6130             return GAP_CONNECTION_SCO;
6131         case BD_ADDR_TYPE_ACL:
6132             return GAP_CONNECTION_ACL;
6133         default:
6134             return GAP_CONNECTION_INVALID;
6135     }
6136 }
6137 
6138 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6139     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6140     if (!conn) return HCI_ROLE_INVALID;
6141     return (hci_role_t) conn->role;
6142 }
6143 
6144 
6145 #ifdef ENABLE_CLASSIC
6146 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6147     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6148     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6149     conn->request_role = role;
6150     hci_run();
6151     return ERROR_CODE_SUCCESS;
6152 }
6153 #endif
6154 
6155 #ifdef ENABLE_BLE
6156 
6157 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){
6158     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6159     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6160 
6161     conn->le_phy_update_all_phys    = all_phys;
6162     conn->le_phy_update_tx_phys     = tx_phys;
6163     conn->le_phy_update_rx_phys     = rx_phys;
6164     conn->le_phy_update_phy_options = phy_options;
6165 
6166     hci_run();
6167 
6168     return 0;
6169 }
6170 
6171 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6172     // check if already in list
6173     btstack_linked_list_iterator_t it;
6174     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6175     while (btstack_linked_list_iterator_has_next(&it)) {
6176         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6177         if (entry->address_type != address_type) {
6178             continue;
6179         }
6180         if (memcmp(entry->address, address, 6) != 0) {
6181             continue;
6182         }
6183 		// disallow if already scheduled to add
6184 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6185 			return ERROR_CODE_COMMAND_DISALLOWED;
6186 		}
6187 		// still on controller, but scheduled to remove -> re-add
6188 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6189 		return ERROR_CODE_SUCCESS;
6190     }
6191     // alloc and add to list
6192     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6193     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6194     entry->address_type = address_type;
6195     (void)memcpy(entry->address, address, 6);
6196     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6197     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6198     return ERROR_CODE_SUCCESS;
6199 }
6200 
6201 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6202     btstack_linked_list_iterator_t it;
6203     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6204     while (btstack_linked_list_iterator_has_next(&it)){
6205         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6206         if (entry->address_type != address_type) {
6207             continue;
6208         }
6209         if (memcmp(entry->address, address, 6) != 0) {
6210             continue;
6211         }
6212         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6213             // remove from controller if already present
6214             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6215         }  else {
6216             // directly remove entry from whitelist
6217             btstack_linked_list_iterator_remove(&it);
6218             btstack_memory_whitelist_entry_free(entry);
6219         }
6220         return ERROR_CODE_SUCCESS;
6221     }
6222     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6223 }
6224 
6225 static void hci_whitelist_clear(void){
6226     btstack_linked_list_iterator_t it;
6227     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6228     while (btstack_linked_list_iterator_has_next(&it)){
6229         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6230         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6231             // remove from controller if already present
6232             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6233             continue;
6234         }
6235         // directly remove entry from whitelist
6236         btstack_linked_list_iterator_remove(&it);
6237         btstack_memory_whitelist_entry_free(entry);
6238     }
6239 }
6240 
6241 // free all entries unconditionally
6242 static void hci_whitelist_free(void){
6243     btstack_linked_list_iterator_t lit;
6244     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
6245     while (btstack_linked_list_iterator_has_next(&lit)){
6246         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
6247         btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
6248         btstack_memory_whitelist_entry_free(entry);
6249     }
6250 }
6251 
6252 /**
6253  * @brief Clear Whitelist
6254  * @return 0 if ok
6255  */
6256 uint8_t gap_whitelist_clear(void){
6257     hci_whitelist_clear();
6258     hci_run();
6259     return ERROR_CODE_SUCCESS;
6260 }
6261 
6262 /**
6263  * @brief Add Device to Whitelist
6264  * @param address_typ
6265  * @param address
6266  * @return 0 if ok
6267  */
6268 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6269     uint8_t status = hci_whitelist_add(address_type, address);
6270     if (status){
6271         return status;
6272     }
6273     hci_run();
6274     return ERROR_CODE_SUCCESS;
6275 }
6276 
6277 /**
6278  * @brief Remove Device from Whitelist
6279  * @param address_typ
6280  * @param address
6281  * @return 0 if ok
6282  */
6283 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6284     uint8_t status = hci_whitelist_remove(address_type, address);
6285     if (status){
6286         return status;
6287     }
6288     hci_run();
6289     return ERROR_CODE_SUCCESS;
6290 }
6291 
6292 #ifdef ENABLE_LE_CENTRAL
6293 /**
6294  * @brief Connect with Whitelist
6295  * @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6296  * @return - if ok
6297  */
6298 uint8_t gap_connect_with_whitelist(void){
6299     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6300         return ERROR_CODE_COMMAND_DISALLOWED;
6301     }
6302     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6303     hci_run();
6304     return ERROR_CODE_SUCCESS;
6305 }
6306 
6307 /**
6308  * @brief Auto Connection Establishment - Start Connecting to device
6309  * @param address_typ
6310  * @param address
6311  * @return 0 if ok
6312  */
6313 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6314     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6315         return ERROR_CODE_COMMAND_DISALLOWED;
6316     }
6317 
6318     uint8_t status = hci_whitelist_add(address_type, address);
6319     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6320         return status;
6321     }
6322 
6323     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6324 
6325     hci_run();
6326     return ERROR_CODE_SUCCESS;
6327 }
6328 
6329 /**
6330  * @brief Auto Connection Establishment - Stop Connecting to device
6331  * @param address_typ
6332  * @param address
6333  * @return 0 if ok
6334  */
6335 uint8_t gap_auto_connection_stop(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     hci_whitelist_remove(address_type, address);
6341     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6342         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6343     }
6344     hci_run();
6345     return 0;
6346 }
6347 
6348 /**
6349  * @brief Auto Connection Establishment - Stop everything
6350  * @note  Convenience function to stop all active auto connection attempts
6351  */
6352 uint8_t gap_auto_connection_stop_all(void){
6353     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6354         return ERROR_CODE_COMMAND_DISALLOWED;
6355     }
6356     hci_whitelist_clear();
6357     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6358     hci_run();
6359     return ERROR_CODE_SUCCESS;
6360 }
6361 
6362 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6363     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6364     if (!conn) return 0;
6365     return conn->le_connection_interval;
6366 }
6367 #endif
6368 #endif
6369 
6370 #ifdef ENABLE_CLASSIC
6371 /**
6372  * @brief Set Extended Inquiry Response data
6373  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6374  * @note has to be done before stack starts up
6375  */
6376 void gap_set_extended_inquiry_response(const uint8_t * data){
6377     hci_stack->eir_data = data;
6378     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6379     hci_run();
6380 }
6381 
6382 /**
6383  * @brief Start GAP Classic Inquiry
6384  * @param duration in 1.28s units
6385  * @return 0 if ok
6386  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6387  */
6388 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6389     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6390     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6391     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6392         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6393     }
6394     hci_stack->inquiry_state = duration_in_1280ms_units;
6395     hci_run();
6396     return 0;
6397 }
6398 
6399 /**
6400  * @brief Stop GAP Classic Inquiry
6401  * @return 0 if ok
6402  */
6403 int gap_inquiry_stop(void){
6404     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6405         // emit inquiry complete event, before it even started
6406         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6407         hci_emit_event(event, sizeof(event), 1);
6408         return 0;
6409     }
6410     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6411     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6412     hci_run();
6413     return 0;
6414 }
6415 
6416 void gap_inquiry_set_lap(uint32_t lap){
6417     hci_stack->inquiry_lap = lap;
6418 }
6419 
6420 void gap_inquiry_set_scan_activity(uint16_t inquiry_scan_interval, uint16_t inquiry_scan_window){
6421     hci_stack->inquiry_scan_interval = inquiry_scan_interval;
6422     hci_stack->inquiry_scan_window   = inquiry_scan_window;
6423     hci_stack->gap_tasks |= GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
6424     hci_run();
6425 }
6426 
6427 
6428 /**
6429  * @brief Remote Name Request
6430  * @param addr
6431  * @param page_scan_repetition_mode
6432  * @param clock_offset only used when bit 15 is set
6433  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6434  */
6435 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6436     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6437     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6438     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6439     hci_stack->remote_name_clock_offset = clock_offset;
6440     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6441     hci_run();
6442     return 0;
6443 }
6444 
6445 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6446     hci_stack->gap_pairing_state = state;
6447     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6448     hci_run();
6449     return 0;
6450 }
6451 
6452 /**
6453  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6454  * @param addr
6455  * @param pin_data
6456  * @param pin_len
6457  * @return 0 if ok
6458  */
6459 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6460     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6461     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6462     hci_stack->gap_pairing_pin_len = pin_len;
6463     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6464 }
6465 
6466 /**
6467  * @brief Legacy Pairing Pin Code Response
6468  * @param addr
6469  * @param pin
6470  * @return 0 if ok
6471  */
6472 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6473     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6474 }
6475 
6476 /**
6477  * @brief Abort Legacy Pairing
6478  * @param addr
6479  * @param pin
6480  * @return 0 if ok
6481  */
6482 int gap_pin_code_negative(bd_addr_t addr){
6483     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6484     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6485 }
6486 
6487 /**
6488  * @brief SSP Passkey Response
6489  * @param addr
6490  * @param passkey
6491  * @return 0 if ok
6492  */
6493 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6494     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6495     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6496     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6497 }
6498 
6499 /**
6500  * @brief Abort SSP Passkey Entry/Pairing
6501  * @param addr
6502  * @param pin
6503  * @return 0 if ok
6504  */
6505 int gap_ssp_passkey_negative(const bd_addr_t addr){
6506     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6507     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6508 }
6509 
6510 /**
6511  * @brief Accept SSP Numeric Comparison
6512  * @param addr
6513  * @param passkey
6514  * @return 0 if ok
6515  */
6516 int gap_ssp_confirmation_response(const bd_addr_t addr){
6517     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6518     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6519 }
6520 
6521 /**
6522  * @brief Abort SSP Numeric Comparison/Pairing
6523  * @param addr
6524  * @param pin
6525  * @return 0 if ok
6526  */
6527 int gap_ssp_confirmation_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_CONFIRMATION_NEGATIVE);
6530 }
6531 
6532 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6533 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6534     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6535     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6536     connectionSetAuthenticationFlags(conn, flag);
6537     hci_run();
6538     return ERROR_CODE_SUCCESS;
6539 }
6540 #endif
6541 
6542 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6543 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6544     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6545 }
6546 
6547 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6548     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6549 }
6550 #endif
6551 
6552 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6553 /**
6554  * @brief Report Remote OOB Data
6555  * @param bd_addr
6556  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6557  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6558  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6559  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6560  */
6561 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){
6562     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6563     if (connection == NULL) {
6564         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6565     }
6566     connection->classic_oob_c_192 = c_192;
6567     connection->classic_oob_r_192 = r_192;
6568 
6569     // ignore P-256 if not supported by us
6570     if (hci_stack->secure_connections_active){
6571         connection->classic_oob_c_256 = c_256;
6572         connection->classic_oob_r_256 = r_256;
6573     }
6574 
6575     return ERROR_CODE_SUCCESS;
6576 }
6577 /**
6578  * @brief Generate new OOB data
6579  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6580  */
6581 void gap_ssp_generate_oob_data(void){
6582     hci_stack->classic_read_local_oob_data = true;
6583     hci_run();
6584 }
6585 
6586 #endif
6587 
6588 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6589 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6590     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6591     if (connection == NULL) {
6592         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6593     }
6594 
6595     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6596     connection->link_key_type = type;
6597 
6598     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6599 }
6600 
6601 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6602 /**
6603  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6604  * @param inquiry_mode see bluetooth_defines.h
6605  */
6606 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6607     hci_stack->inquiry_mode = inquiry_mode;
6608 }
6609 
6610 /**
6611  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6612  */
6613 void hci_set_sco_voice_setting(uint16_t voice_setting){
6614     hci_stack->sco_voice_setting = voice_setting;
6615 }
6616 
6617 /**
6618  * @brief Get SCO Voice Setting
6619  * @return current voice setting
6620  */
6621 uint16_t hci_get_sco_voice_setting(void){
6622     return hci_stack->sco_voice_setting;
6623 }
6624 
6625 static int hci_have_usb_transport(void){
6626     if (!hci_stack->hci_transport) return 0;
6627     const char * transport_name = hci_stack->hci_transport->name;
6628     if (!transport_name) return 0;
6629     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6630 }
6631 
6632 /** @brief Get SCO packet length for current SCO Voice setting
6633  *  @note  Using SCO packets of the exact length is required for USB transfer
6634  *  @return Length of SCO packets in bytes (not audio frames)
6635  */
6636 uint16_t hci_get_sco_packet_length(void){
6637     uint16_t sco_packet_length = 0;
6638 
6639 #ifdef ENABLE_SCO_OVER_HCI
6640     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6641     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6642 
6643     if (hci_have_usb_transport()){
6644         // see Core Spec for H2 USB Transfer.
6645         // 3 byte SCO header + 24 bytes per connection
6646         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6647         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6648     } else {
6649         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6650         sco_packet_length = 3 + 60 * multiplier;
6651         // assert that it still fits inside an SCO buffer
6652         if (sco_packet_length > hci_stack->sco_data_packet_length){
6653             sco_packet_length = 3 + 60;
6654         }
6655     }
6656 #endif
6657 
6658 #ifdef HAVE_SCO_TRANSPORT
6659     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6660     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6661     sco_packet_length = 3 + 60 * multiplier;
6662 #endif
6663     return sco_packet_length;
6664 }
6665 
6666 /**
6667 * @brief Sets the master/slave policy
6668 * @param policy (0: attempt to become master, 1: let connecting device decide)
6669 */
6670 void hci_set_master_slave_policy(uint8_t policy){
6671     hci_stack->master_slave_policy = policy;
6672 }
6673 
6674 #endif
6675 
6676 HCI_STATE hci_get_state(void){
6677     return hci_stack->state;
6678 }
6679 
6680 #ifdef ENABLE_CLASSIC
6681 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6682     hci_stack->gap_classic_accept_callback = accept_callback;
6683 }
6684 #endif
6685 
6686 /**
6687  * @brief Set callback for Bluetooth Hardware Error
6688  */
6689 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6690     hci_stack->hardware_error_callback = fn;
6691 }
6692 
6693 void hci_disconnect_all(void){
6694     btstack_linked_list_iterator_t it;
6695     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6696     while (btstack_linked_list_iterator_has_next(&it)){
6697         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6698         if (con->state == SENT_DISCONNECT) continue;
6699         con->state = SEND_DISCONNECT;
6700     }
6701     hci_run();
6702 }
6703 
6704 uint16_t hci_get_manufacturer(void){
6705     return hci_stack->manufacturer;
6706 }
6707 
6708 #ifdef ENABLE_BLE
6709 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6710     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6711     if (!hci_con) return NULL;
6712     return &hci_con->sm_connection;
6713 }
6714 
6715 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6716 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6717 #endif
6718 
6719 int gap_encryption_key_size(hci_con_handle_t con_handle){
6720     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6721     if (hci_connection == NULL) return 0;
6722     if (hci_is_le_connection(hci_connection)){
6723 #ifdef ENABLE_BLE
6724         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6725         if (sm_conn->sm_connection_encrypted) {
6726             return sm_conn->sm_actual_encryption_key_size;
6727         }
6728 #endif
6729     } else {
6730 #ifdef ENABLE_CLASSIC
6731         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6732             return hci_connection->encryption_key_size;
6733         }
6734 #endif
6735     }
6736     return 0;
6737 }
6738 
6739 int gap_authenticated(hci_con_handle_t con_handle){
6740     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6741     if (hci_connection == NULL) return 0;
6742 
6743     switch (hci_connection->address_type){
6744 #ifdef ENABLE_BLE
6745         case BD_ADDR_TYPE_LE_PUBLIC:
6746         case BD_ADDR_TYPE_LE_RANDOM:
6747             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6748             return hci_connection->sm_connection.sm_connection_authenticated;
6749 #endif
6750 #ifdef ENABLE_CLASSIC
6751         case BD_ADDR_TYPE_SCO:
6752         case BD_ADDR_TYPE_ACL:
6753             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6754 #endif
6755         default:
6756             return 0;
6757     }
6758 }
6759 
6760 int gap_secure_connection(hci_con_handle_t con_handle){
6761     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6762     if (hci_connection == NULL) return 0;
6763 
6764     switch (hci_connection->address_type){
6765 #ifdef ENABLE_BLE
6766         case BD_ADDR_TYPE_LE_PUBLIC:
6767         case BD_ADDR_TYPE_LE_RANDOM:
6768             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6769             return hci_connection->sm_connection.sm_connection_sc;
6770 #endif
6771 #ifdef ENABLE_CLASSIC
6772         case BD_ADDR_TYPE_SCO:
6773         case BD_ADDR_TYPE_ACL:
6774             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6775 #endif
6776         default:
6777             return 0;
6778     }
6779 }
6780 
6781 bool gap_bonded(hci_con_handle_t con_handle){
6782 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6783 	if (hci_connection == NULL) return 0;
6784 
6785 #ifdef ENABLE_CLASSIC
6786 	link_key_t link_key;
6787 	link_key_type_t link_key_type;
6788 #endif
6789 	switch (hci_connection->address_type){
6790 #ifdef ENABLE_BLE
6791 		case BD_ADDR_TYPE_LE_PUBLIC:
6792 		case BD_ADDR_TYPE_LE_RANDOM:
6793 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6794 #endif
6795 #ifdef ENABLE_CLASSIC
6796 		case BD_ADDR_TYPE_SCO:
6797 		case BD_ADDR_TYPE_ACL:
6798 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6799 #endif
6800 		default:
6801 			return false;
6802 	}
6803 }
6804 
6805 #ifdef ENABLE_BLE
6806 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6807     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6808     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6809     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6810     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6811     return sm_conn->sm_connection_authorization_state;
6812 }
6813 #endif
6814 
6815 #ifdef ENABLE_CLASSIC
6816 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){
6817     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6818     if (!conn) return GAP_CONNECTION_INVALID;
6819     conn->sniff_min_interval = sniff_min_interval;
6820     conn->sniff_max_interval = sniff_max_interval;
6821     conn->sniff_attempt = sniff_attempt;
6822     conn->sniff_timeout = sniff_timeout;
6823     hci_run();
6824     return 0;
6825 }
6826 
6827 /**
6828  * @brief Exit Sniff mode
6829  * @param con_handle
6830  @ @return 0 if ok
6831  */
6832 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6833     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6834     if (!conn) return GAP_CONNECTION_INVALID;
6835     conn->sniff_min_interval = 0xffff;
6836     hci_run();
6837     return 0;
6838 }
6839 
6840 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){
6841     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6842     if (!conn) return GAP_CONNECTION_INVALID;
6843     conn->sniff_subrating_max_latency = max_latency;
6844     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6845     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6846     hci_run();
6847     return ERROR_CODE_SUCCESS;
6848 }
6849 
6850 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){
6851     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6852     if (!conn) return GAP_CONNECTION_INVALID;
6853     conn->qos_service_type = service_type;
6854     conn->qos_token_rate = token_rate;
6855     conn->qos_peak_bandwidth = peak_bandwidth;
6856     conn->qos_latency = latency;
6857     conn->qos_delay_variation = delay_variation;
6858     hci_run();
6859     return ERROR_CODE_SUCCESS;
6860 }
6861 
6862 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6863     hci_stack->new_page_scan_interval = page_scan_interval;
6864     hci_stack->new_page_scan_window = page_scan_window;
6865     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6866     hci_run();
6867 }
6868 
6869 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6870     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6871     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6872     hci_run();
6873 }
6874 
6875 void gap_set_page_timeout(uint16_t page_timeout){
6876     hci_stack->page_timeout = page_timeout;
6877     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_TIMEOUT;
6878     hci_run();
6879 }
6880 
6881 #endif
6882 
6883 void hci_halting_defer(void){
6884     if (hci_stack->state != HCI_STATE_HALTING) return;
6885     switch (hci_stack->substate){
6886         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6887         case HCI_HALTING_CLOSE:
6888             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6889             break;
6890         default:
6891             break;
6892     }
6893 }
6894 
6895 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6896 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6897     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6898     if (le_device_db_index >= le_device_db_max_count()) return;
6899     uint8_t offset = le_device_db_index >> 3;
6900     uint8_t mask = 1 << (le_device_db_index & 7);
6901     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6902     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6903     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6904         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6905     }
6906 }
6907 
6908 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6909 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6910 	if (le_device_db_index >= le_device_db_max_count()) return;
6911 	uint8_t offset = le_device_db_index >> 3;
6912 	uint8_t mask = 1 << (le_device_db_index & 7);
6913 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6914 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6915 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6916 	}
6917 }
6918 
6919 uint8_t gap_load_resolving_list_from_le_device_db(void){
6920 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6921 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6922 	}
6923 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6924 		// restart le resolving list update
6925 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6926 	}
6927 	return ERROR_CODE_SUCCESS;
6928 }
6929 #endif
6930 
6931 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6932 void hci_setup_test_connections_fuzz(void){
6933     hci_connection_t * conn;
6934 
6935     // default address: 66:55:44:33:00:01
6936     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6937 
6938     // setup Controller info
6939     hci_stack->num_cmd_packets = 255;
6940     hci_stack->acl_packets_total_num = 255;
6941 
6942     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6943     addr[5] = 0x01;
6944     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6945     conn->con_handle = addr[5];
6946     conn->role  = HCI_ROLE_SLAVE;
6947     conn->state = RECEIVED_CONNECTION_REQUEST;
6948     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6949 
6950     // setup incoming Classic SCO connection with con handle 0x0002
6951     addr[5] = 0x02;
6952     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6953     conn->con_handle = addr[5];
6954     conn->role  = HCI_ROLE_SLAVE;
6955     conn->state = RECEIVED_CONNECTION_REQUEST;
6956     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6957 
6958     // setup ready Classic ACL connection with con handle 0x0003
6959     addr[5] = 0x03;
6960     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6961     conn->con_handle = addr[5];
6962     conn->role  = HCI_ROLE_SLAVE;
6963     conn->state = OPEN;
6964     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6965 
6966     // setup ready Classic SCO connection with con handle 0x0004
6967     addr[5] = 0x04;
6968     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6969     conn->con_handle = addr[5];
6970     conn->role  = HCI_ROLE_SLAVE;
6971     conn->state = OPEN;
6972     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6973 
6974     // setup ready LE ACL connection with con handle 0x005 and public address
6975     addr[5] = 0x05;
6976     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6977     conn->con_handle = addr[5];
6978     conn->role  = HCI_ROLE_SLAVE;
6979     conn->state = OPEN;
6980     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6981     conn->sm_connection.sm_connection_encrypted = 1;
6982 }
6983 
6984 void hci_free_connections_fuzz(void){
6985     btstack_linked_list_iterator_t it;
6986     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6987     while (btstack_linked_list_iterator_has_next(&it)){
6988         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6989         btstack_linked_list_iterator_remove(&it);
6990         btstack_memory_hci_connection_free(con);
6991     }
6992 }
6993 void hci_simulate_working_fuzz(void){
6994     hci_init_done();
6995     hci_stack->num_cmd_packets = 255;
6996 }
6997 #endif
6998