xref: /btstack/src/hci.c (revision 6d34f98e0c6a035be904a5ac00e86a7b4f285631)
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 MATTHIAS
24  * RINGWALD 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 HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->role = HCI_ROLE_INVALID;
199     conn->address_type = addr_type;
200     conn->con_handle = 0xffff;
201     conn->authentication_flags = AUTH_FLAGS_NONE;
202     conn->bonding_flags = 0;
203     conn->requested_security_level = LEVEL_0;
204 #ifdef ENABLE_CLASSIC
205     conn->request_role = HCI_ROLE_INVALID;
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     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
222     return conn;
223 }
224 
225 
226 /**
227  * get le connection parameter range
228 *
229  * @return le connection parameter range struct
230  */
231 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
232     *range = hci_stack->le_connection_parameter_range;
233 }
234 
235 /**
236  * set le connection parameter range
237  *
238  */
239 
240 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
241     hci_stack->le_connection_parameter_range = *range;
242 }
243 
244 /**
245  * @brief Test if connection parameters are inside in existing rage
246  * @param conn_interval_min (unit: 1.25ms)
247  * @param conn_interval_max (unit: 1.25ms)
248  * @param conn_latency
249  * @param supervision_timeout (unit: 10ms)
250  * @returns 1 if included
251  */
252 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){
253     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
254     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
255 
256     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
257     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
258 
259     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
260     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
261 
262     return 1;
263 }
264 
265 /**
266  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
267  * @note: default: 1
268  * @param max_peripheral_connections
269  */
270 #ifdef ENABLE_LE_PERIPHERAL
271 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
272     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
273 }
274 #endif
275 
276 /**
277  * get hci connections iterator
278  *
279  * @return hci connections iterator
280  */
281 
282 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
283     btstack_linked_list_iterator_init(it, &hci_stack->connections);
284 }
285 
286 /**
287  * get connection for a given handle
288  *
289  * @return connection OR NULL, if not found
290  */
291 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
292     btstack_linked_list_iterator_t it;
293     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
294     while (btstack_linked_list_iterator_has_next(&it)){
295         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
296         if ( item->con_handle == con_handle ) {
297             return item;
298         }
299     }
300     return NULL;
301 }
302 
303 /**
304  * get connection for given address
305  *
306  * @return connection OR NULL, if not found
307  */
308 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
309     btstack_linked_list_iterator_t it;
310     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
311     while (btstack_linked_list_iterator_has_next(&it)){
312         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
313         if (connection->address_type != addr_type)  continue;
314         if (memcmp(addr, connection->address, 6) != 0) continue;
315         return connection;
316     }
317     return NULL;
318 }
319 
320 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
321     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
322 }
323 
324 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
325     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
326 }
327 
328 #ifdef ENABLE_CLASSIC
329 
330 #ifdef ENABLE_SCO_OVER_HCI
331 static int hci_number_sco_connections(void){
332     int connections = 0;
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
338         connections++;
339     }
340     return connections;
341 }
342 #endif
343 
344 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
345     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
346 #ifdef HAVE_EMBEDDED_TICK
347     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
348         // connections might be timed out
349         hci_emit_l2cap_check_timeout(connection);
350     }
351 #else
352     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
353         // connections might be timed out
354         hci_emit_l2cap_check_timeout(connection);
355     }
356 #endif
357 }
358 
359 static void hci_connection_timestamp(hci_connection_t *connection){
360 #ifdef HAVE_EMBEDDED_TICK
361     connection->timestamp = btstack_run_loop_embedded_get_ticks();
362 #else
363     connection->timestamp = btstack_run_loop_get_time_ms();
364 #endif
365 }
366 
367 /**
368  * add authentication flags and reset timer
369  * @note: assumes classic connection
370  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
371  */
372 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
373     bd_addr_t addr;
374     reverse_bd_addr(bd_addr, addr);
375     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
376     if (conn) {
377         connectionSetAuthenticationFlags(conn, flags);
378         hci_connection_timestamp(conn);
379     }
380 }
381 
382 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
383     hci_connection_t * conn = hci_connection_for_handle(handle);
384     if (!conn) return 0;
385     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
386     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
387     return 0;
388 }
389 
390 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
391     if (!hci_stack->link_key_db) return;
392     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
393     hci_stack->link_key_db->delete_link_key(addr);
394 }
395 
396 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
397     if (!hci_stack->link_key_db) return;
398     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
399     hci_stack->link_key_db->put_link_key(addr, link_key, type);
400 }
401 
402 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
403 	if (!hci_stack->link_key_db) return false;
404 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
405 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
406 	return result;
407 }
408 
409 void gap_delete_all_link_keys(void){
410     bd_addr_t  addr;
411     link_key_t link_key;
412     link_key_type_t type;
413     btstack_link_key_iterator_t it;
414     int ok = gap_link_key_iterator_init(&it);
415     if (!ok) {
416         log_error("could not initialize iterator");
417         return;
418     }
419     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
420         gap_drop_link_key_for_bd_addr(addr);
421     }
422     gap_link_key_iterator_done(&it);
423 }
424 
425 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
426     if (!hci_stack->link_key_db) return 0;
427     if (!hci_stack->link_key_db->iterator_init) return 0;
428     return hci_stack->link_key_db->iterator_init(it);
429 }
430 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){
431     if (!hci_stack->link_key_db) return 0;
432     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
433 }
434 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
435     if (!hci_stack->link_key_db) return;
436     hci_stack->link_key_db->iterator_done(it);
437 }
438 #endif
439 
440 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
441     switch (address_type){
442         case BD_ADDR_TYPE_LE_PUBLIC:
443         case BD_ADDR_TYPE_LE_RANDOM:
444         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
445         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
446             return true;
447         default:
448             return false;
449     }
450 }
451 
452 static int hci_is_le_connection(hci_connection_t * connection){
453     return hci_is_le_connection_type(connection->address_type);
454 }
455 
456 /**
457  * count connections
458  */
459 static int nr_hci_connections(void){
460     int count = 0;
461     btstack_linked_item_t *it;
462     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
463         count++;
464     }
465     return count;
466 }
467 
468 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
469 
470     unsigned int num_packets_sent_classic = 0;
471     unsigned int num_packets_sent_le = 0;
472 
473     btstack_linked_item_t *it;
474     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
475         hci_connection_t * connection = (hci_connection_t *) it;
476         if (hci_is_le_connection(connection)){
477             num_packets_sent_le += connection->num_packets_sent;
478         }
479         if (connection->address_type == BD_ADDR_TYPE_ACL){
480             num_packets_sent_classic += connection->num_packets_sent;
481         }
482     }
483     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
484     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
485     int free_slots_le = 0;
486 
487     if (free_slots_classic < 0){
488         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);
489         return 0;
490     }
491 
492     if (hci_stack->le_acl_packets_total_num){
493         // if we have LE slots, they are used
494         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
495         if (free_slots_le < 0){
496             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);
497             return 0;
498         }
499     } else {
500         // otherwise, classic slots are used for LE, too
501         free_slots_classic -= num_packets_sent_le;
502         if (free_slots_classic < 0){
503             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);
504             return 0;
505         }
506     }
507 
508     switch (address_type){
509         case BD_ADDR_TYPE_UNKNOWN:
510             log_error("hci_number_free_acl_slots: unknown address type");
511             return 0;
512 
513         case BD_ADDR_TYPE_ACL:
514             return free_slots_classic;
515 
516         default:
517            if (hci_stack->le_acl_packets_total_num){
518                return free_slots_le;
519            }
520            return free_slots_classic;
521     }
522 }
523 
524 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
525     // get connection type
526     hci_connection_t * connection = hci_connection_for_handle(con_handle);
527     if (!connection){
528         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
529         return 0;
530     }
531     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
532 }
533 
534 #ifdef ENABLE_CLASSIC
535 static int hci_number_free_sco_slots(void){
536     unsigned int num_sco_packets_sent  = 0;
537     btstack_linked_item_t *it;
538     if (hci_stack->synchronous_flow_control_enabled){
539         // explicit flow control
540         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
541             hci_connection_t * connection = (hci_connection_t *) it;
542             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
543             num_sco_packets_sent += connection->num_packets_sent;
544         }
545         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
546             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
547             return 0;
548         }
549         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
550     } else {
551         // implicit flow control -- TODO
552         int num_ready = 0;
553         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
554             hci_connection_t * connection = (hci_connection_t *) it;
555             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
556             if (connection->sco_tx_ready == 0) continue;
557             num_ready++;
558         }
559         return num_ready;
560     }
561 }
562 #endif
563 
564 // only used to send HCI Host Number Completed Packets
565 static int hci_can_send_comand_packet_transport(void){
566     if (hci_stack->hci_packet_buffer_reserved) return 0;
567 
568     // check for async hci transport implementations
569     if (hci_stack->hci_transport->can_send_packet_now){
570         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
571             return 0;
572         }
573     }
574     return 1;
575 }
576 
577 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
578 int hci_can_send_command_packet_now(void){
579     if (hci_can_send_comand_packet_transport() == 0) return 0;
580     return hci_stack->num_cmd_packets > 0u;
581 }
582 
583 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
584     // check for async hci transport implementations
585     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
586     return hci_stack->hci_transport->can_send_packet_now(packet_type);
587 }
588 
589 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
590     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
591     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
592 }
593 
594 int hci_can_send_acl_le_packet_now(void){
595     if (hci_stack->hci_packet_buffer_reserved) return 0;
596     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
597 }
598 
599 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
600     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
601     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
602 }
603 
604 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
605     if (hci_stack->hci_packet_buffer_reserved) return 0;
606     return hci_can_send_prepared_acl_packet_now(con_handle);
607 }
608 
609 #ifdef ENABLE_CLASSIC
610 int hci_can_send_acl_classic_packet_now(void){
611     if (hci_stack->hci_packet_buffer_reserved) return 0;
612     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
613 }
614 
615 int hci_can_send_prepared_sco_packet_now(void){
616     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
617     if (hci_have_usb_transport()){
618         return hci_stack->sco_can_send_now;
619     } else {
620         return hci_number_free_sco_slots() > 0;
621     }
622 }
623 
624 int hci_can_send_sco_packet_now(void){
625     if (hci_stack->hci_packet_buffer_reserved) return 0;
626     return hci_can_send_prepared_sco_packet_now();
627 }
628 
629 void hci_request_sco_can_send_now_event(void){
630     hci_stack->sco_waiting_for_can_send_now = 1;
631     hci_notify_if_sco_can_send_now();
632 }
633 #endif
634 
635 // used for internal checks in l2cap.c
636 int hci_is_packet_buffer_reserved(void){
637     return hci_stack->hci_packet_buffer_reserved;
638 }
639 
640 // reserves outgoing packet buffer. @returns 1 if successful
641 int hci_reserve_packet_buffer(void){
642     if (hci_stack->hci_packet_buffer_reserved) {
643         log_error("hci_reserve_packet_buffer called but buffer already reserved");
644         return 0;
645     }
646     hci_stack->hci_packet_buffer_reserved = 1;
647     return 1;
648 }
649 
650 void hci_release_packet_buffer(void){
651     hci_stack->hci_packet_buffer_reserved = 0;
652 }
653 
654 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
655 static int hci_transport_synchronous(void){
656     return hci_stack->hci_transport->can_send_packet_now == NULL;
657 }
658 
659 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
660 
661     // 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);
662 
663     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
664     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
665     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
666         max_acl_data_packet_length = hci_stack->le_data_packets_length;
667     }
668 
669 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
670     if (hci_is_le_connection(connection)){
671         max_acl_data_packet_length = connection->le_max_tx_octets;
672     }
673 #endif
674 
675     log_debug("hci_send_acl_packet_fragments entered");
676 
677     int err;
678     // multiple packets could be send on a synchronous HCI transport
679     while (true){
680 
681         log_debug("hci_send_acl_packet_fragments loop entered");
682 
683         // get current data
684         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
685         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
686         int more_fragments = 0;
687 
688         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
689         if (current_acl_data_packet_length > max_acl_data_packet_length){
690             more_fragments = 1;
691             current_acl_data_packet_length = max_acl_data_packet_length;
692         }
693 
694         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
695         if (acl_header_pos > 0u){
696             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
697             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
698             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
699         }
700 
701         // update header len
702         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
703 
704         // count packet
705         connection->num_packets_sent++;
706         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
707 
708         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
709         if (more_fragments){
710             // update start of next fragment to send
711             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
712         } else {
713             // done
714             hci_stack->acl_fragmentation_pos = 0;
715             hci_stack->acl_fragmentation_total_size = 0;
716         }
717 
718         // send packet
719         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
720         const int size = current_acl_data_packet_length + 4;
721         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
722         hci_stack->acl_fragmentation_tx_active = 1;
723         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
724 
725         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
726 
727         // done yet?
728         if (!more_fragments) break;
729 
730         // can send more?
731         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
732     }
733 
734     log_debug("hci_send_acl_packet_fragments loop over");
735 
736     // release buffer now for synchronous transport
737     if (hci_transport_synchronous()){
738         hci_stack->acl_fragmentation_tx_active = 0;
739         hci_release_packet_buffer();
740         hci_emit_transport_packet_sent();
741     }
742 
743     return err;
744 }
745 
746 // pre: caller has reserved the packet buffer
747 int hci_send_acl_packet_buffer(int size){
748 
749     // log_info("hci_send_acl_packet_buffer size %u", size);
750 
751     if (!hci_stack->hci_packet_buffer_reserved) {
752         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
753         return 0;
754     }
755 
756     uint8_t * packet = hci_stack->hci_packet_buffer;
757     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
758 
759     // check for free places on Bluetooth module
760     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
761         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
762         hci_release_packet_buffer();
763         hci_emit_transport_packet_sent();
764         return BTSTACK_ACL_BUFFERS_FULL;
765     }
766 
767     hci_connection_t *connection = hci_connection_for_handle( con_handle);
768     if (!connection) {
769         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
770         hci_release_packet_buffer();
771         hci_emit_transport_packet_sent();
772         return 0;
773     }
774 
775 #ifdef ENABLE_CLASSIC
776     hci_connection_timestamp(connection);
777 #endif
778 
779     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
780 
781     // setup data
782     hci_stack->acl_fragmentation_total_size = size;
783     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
784 
785     return hci_send_acl_packet_fragments(connection);
786 }
787 
788 #ifdef ENABLE_CLASSIC
789 // pre: caller has reserved the packet buffer
790 int hci_send_sco_packet_buffer(int size){
791 
792     // log_info("hci_send_acl_packet_buffer size %u", size);
793 
794     if (!hci_stack->hci_packet_buffer_reserved) {
795         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
796         return 0;
797     }
798 
799     uint8_t * packet = hci_stack->hci_packet_buffer;
800 
801     // skip checks in loopback mode
802     if (!hci_stack->loopback_mode){
803         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
804 
805         // check for free places on Bluetooth module
806         if (!hci_can_send_prepared_sco_packet_now()) {
807             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
808             hci_release_packet_buffer();
809             hci_emit_transport_packet_sent();
810             return BTSTACK_ACL_BUFFERS_FULL;
811         }
812 
813         // track send packet in connection struct
814         hci_connection_t *connection = hci_connection_for_handle( con_handle);
815         if (!connection) {
816             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
817             hci_release_packet_buffer();
818             hci_emit_transport_packet_sent();
819             return 0;
820         }
821 
822         if (hci_have_usb_transport()){
823             // token used
824             hci_stack->sco_can_send_now = 0;
825         } else {
826             if (hci_stack->synchronous_flow_control_enabled){
827                 connection->num_packets_sent++;
828             } else {
829                 connection->sco_tx_ready--;
830             }
831         }
832     }
833 
834     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
835     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
836 
837     if (hci_transport_synchronous()){
838         hci_release_packet_buffer();
839         hci_emit_transport_packet_sent();
840     }
841 
842     return err;
843 }
844 #endif
845 
846 static void acl_handler(uint8_t *packet, uint16_t size){
847 
848     // get info
849     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
850     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
851     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
852     uint16_t acl_length         = READ_ACL_LENGTH(packet);
853 
854     // ignore non-registered handle
855     if (!conn){
856         log_error("acl_handler called with non-registered handle %u!" , con_handle);
857         return;
858     }
859 
860     // assert packet is complete
861     if ((acl_length + 4u) != size){
862         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
863         return;
864     }
865 
866 #ifdef ENABLE_CLASSIC
867     // update idle timestamp
868     hci_connection_timestamp(conn);
869 #endif
870 
871 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
872     hci_stack->host_completed_packets = 1;
873     conn->num_packets_completed++;
874 #endif
875 
876     // handle different packet types
877     switch (acl_flags & 0x03u) {
878 
879         case 0x01: // continuation fragment
880 
881             // sanity checks
882             if (conn->acl_recombination_pos == 0u) {
883                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
884                 return;
885             }
886             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
887                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
888                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
889                 conn->acl_recombination_pos = 0;
890                 return;
891             }
892 
893             // append fragment payload (header already stored)
894             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
895                          &packet[4], acl_length);
896             conn->acl_recombination_pos += acl_length;
897 
898             // forward complete L2CAP packet if complete.
899             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
900                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
901                 // reset recombination buffer
902                 conn->acl_recombination_length = 0;
903                 conn->acl_recombination_pos = 0;
904             }
905             break;
906 
907         case 0x02: { // first fragment
908 
909             // sanity check
910             if (conn->acl_recombination_pos) {
911                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
912                 conn->acl_recombination_pos = 0;
913             }
914 
915             // peek into L2CAP packet!
916             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
917 
918             // compare fragment size to L2CAP packet size
919             if (acl_length >= (l2cap_length + 4u)){
920                 // forward fragment as L2CAP packet
921                 hci_emit_acl_packet(packet, acl_length + 4u);
922             } else {
923 
924                 if (acl_length > HCI_ACL_BUFFER_SIZE){
925                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
926                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
927                     return;
928                 }
929 
930                 // store first fragment and tweak acl length for complete package
931                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
932                              packet, acl_length + 4u);
933                 conn->acl_recombination_pos    = acl_length + 4u;
934                 conn->acl_recombination_length = l2cap_length;
935                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
936             }
937             break;
938 
939         }
940         default:
941             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
942             return;
943     }
944 
945     // execute main loop
946     hci_run();
947 }
948 
949 static void hci_shutdown_connection(hci_connection_t *conn){
950     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
951 
952 #ifdef ENABLE_CLASSIC
953 #ifdef ENABLE_SCO_OVER_HCI
954     int addr_type = conn->address_type;
955 #endif
956 #endif
957 
958     btstack_run_loop_remove_timer(&conn->timeout);
959 
960     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
961     btstack_memory_hci_connection_free( conn );
962 
963     // now it's gone
964     hci_emit_nr_connections_changed();
965 
966 #ifdef ENABLE_CLASSIC
967 #ifdef ENABLE_SCO_OVER_HCI
968     // update SCO
969     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
970         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
971     }
972 #endif
973 #endif
974 }
975 
976 #ifdef ENABLE_CLASSIC
977 
978 static const uint16_t packet_type_sizes[] = {
979     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
980     HCI_ACL_DH1_SIZE, 0, 0, 0,
981     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
982     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
983 };
984 static const uint8_t  packet_type_feature_requirement_bit[] = {
985      0, // 3 slot packets
986      1, // 5 slot packets
987     25, // EDR 2 mpbs
988     26, // EDR 3 mbps
989     39, // 3 slot EDR packts
990     40, // 5 slot EDR packet
991 };
992 static const uint16_t packet_type_feature_packet_mask[] = {
993     0x0f00, // 3 slot packets
994     0xf000, // 5 slot packets
995     0x1102, // EDR 2 mpbs
996     0x2204, // EDR 3 mbps
997     0x0300, // 3 slot EDR packts
998     0x3000, // 5 slot EDR packet
999 };
1000 
1001 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1002     // enable packet types based on size
1003     uint16_t packet_types = 0;
1004     unsigned int i;
1005     for (i=0;i<16;i++){
1006         if (packet_type_sizes[i] == 0) continue;
1007         if (packet_type_sizes[i] <= buffer_size){
1008             packet_types |= 1 << i;
1009         }
1010     }
1011     // disable packet types due to missing local supported features
1012     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1013         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1014         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1015         if (feature_set) continue;
1016         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1017         packet_types &= ~packet_type_feature_packet_mask[i];
1018     }
1019     // flip bits for "may not be used"
1020     packet_types ^= 0x3306;
1021     return packet_types;
1022 }
1023 
1024 uint16_t hci_usable_acl_packet_types(void){
1025     return hci_stack->packet_types;
1026 }
1027 #endif
1028 
1029 uint8_t* hci_get_outgoing_packet_buffer(void){
1030     // hci packet buffer is >= acl data packet length
1031     return hci_stack->hci_packet_buffer;
1032 }
1033 
1034 uint16_t hci_max_acl_data_packet_length(void){
1035     return hci_stack->acl_data_packet_length;
1036 }
1037 
1038 #ifdef ENABLE_CLASSIC
1039 int hci_extended_sco_link_supported(void){
1040     // No. 31, byte 3, bit 7
1041     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1042 }
1043 #endif
1044 
1045 int hci_non_flushable_packet_boundary_flag_supported(void){
1046     // No. 54, byte 6, bit 6
1047     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1048 }
1049 
1050 static int gap_ssp_supported(void){
1051     // No. 51, byte 6, bit 3
1052     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1053 }
1054 
1055 static int hci_classic_supported(void){
1056 #ifdef ENABLE_CLASSIC
1057     // No. 37, byte 4, bit 5, = No BR/EDR Support
1058     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1059 #else
1060     return 0;
1061 #endif
1062 }
1063 
1064 static int hci_le_supported(void){
1065 #ifdef ENABLE_BLE
1066     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1067     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1068 #else
1069     return 0;
1070 #endif
1071 }
1072 
1073 #ifdef ENABLE_BLE
1074 
1075 /**
1076  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1077  */
1078 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1079     *addr_type = hci_stack->le_own_addr_type;
1080     if (hci_stack->le_own_addr_type){
1081         (void)memcpy(addr, hci_stack->le_random_address, 6);
1082     } else {
1083         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1084     }
1085 }
1086 
1087 #ifdef ENABLE_LE_CENTRAL
1088 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1089 
1090     int offset = 3;
1091     int num_reports = packet[offset];
1092     offset += 1;
1093 
1094     int i;
1095     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1096     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1097     for (i=0; (i<num_reports) && (offset < size);i++){
1098         // sanity checks on data_length:
1099         uint8_t data_length = packet[offset + 8];
1100         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1101         if ((offset + 9u + data_length + 1u) > size)    return;
1102         // setup event
1103         uint8_t event_size = 10u + data_length;
1104         int pos = 0;
1105         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1106         event[pos++] = event_size;
1107         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1108         offset += 8;
1109         pos += 8;
1110         event[pos++] = packet[offset + 1 + data_length]; // rssi
1111         event[pos++] = data_length;
1112         offset++;
1113         (void)memcpy(&event[pos], &packet[offset], data_length);
1114         pos +=    data_length;
1115         offset += data_length + 1u; // rssi
1116         hci_emit_event(event, pos, 1);
1117     }
1118 }
1119 #endif
1120 #endif
1121 
1122 #ifdef ENABLE_BLE
1123 #ifdef ENABLE_LE_PERIPHERAL
1124 static void hci_update_advertisements_enabled_for_current_roles(void){
1125     if (hci_stack->le_advertisements_enabled){
1126         // get number of active le slave connections
1127         int num_slave_connections = 0;
1128         btstack_linked_list_iterator_t it;
1129         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1130         while (btstack_linked_list_iterator_has_next(&it)){
1131             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1132             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1133             if (con->state != OPEN) continue;
1134             if (con->role  != HCI_ROLE_SLAVE) continue;
1135             if (!hci_is_le_connection(con)) continue;
1136             num_slave_connections++;
1137         }
1138         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1139         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1140     } else {
1141         hci_stack->le_advertisements_enabled_for_current_roles = false;
1142     }
1143 }
1144 #endif
1145 #endif
1146 
1147 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1148 
1149 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1150     if (!hci_stack->config) return 0;
1151     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1152     // Limit baud rate for Broadcom chipsets to 3 mbps
1153     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1154         baud_rate = 3000000;
1155     }
1156     return baud_rate;
1157 }
1158 
1159 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1160     UNUSED(ds);
1161 
1162     switch (hci_stack->substate){
1163         case HCI_INIT_W4_SEND_RESET:
1164             log_info("Resend HCI Reset");
1165             hci_stack->substate = HCI_INIT_SEND_RESET;
1166             hci_stack->num_cmd_packets = 1;
1167             hci_run();
1168             break;
1169         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1170             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1171             if (hci_stack->hci_transport->reset_link){
1172                 hci_stack->hci_transport->reset_link();
1173             }
1174 
1175             /* fall through */
1176 
1177         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1178             log_info("Resend HCI Reset - CSR Warm Boot");
1179             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1180             hci_stack->num_cmd_packets = 1;
1181             hci_run();
1182             break;
1183         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1184             if (hci_stack->hci_transport->set_baudrate){
1185                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1186                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1187                 hci_stack->hci_transport->set_baudrate(baud_rate);
1188             }
1189             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1190             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1191                 if (hci_stack->hci_transport->reset_link){
1192                     log_info("Link Reset");
1193                     hci_stack->hci_transport->reset_link();
1194                 }
1195                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1196                 hci_run();
1197             }
1198             break;
1199         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1200             // otherwise continue
1201             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1202             hci_send_cmd(&hci_read_local_supported_commands);
1203             break;
1204         default:
1205             break;
1206     }
1207 }
1208 #endif
1209 
1210 static void hci_initializing_next_state(void){
1211     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1212 }
1213 
1214 // assumption: hci_can_send_command_packet_now() == true
1215 static void hci_initializing_run(void){
1216     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1217     switch (hci_stack->substate){
1218         case HCI_INIT_SEND_RESET:
1219             hci_state_reset();
1220 
1221 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1222             // prepare reset if command complete not received in 100ms
1223             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1224             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1225             btstack_run_loop_add_timer(&hci_stack->timeout);
1226 #endif
1227             // send command
1228             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1229             hci_send_cmd(&hci_reset);
1230             break;
1231         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1232             hci_send_cmd(&hci_read_local_version_information);
1233             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1234             break;
1235         case HCI_INIT_SEND_READ_LOCAL_NAME:
1236             hci_send_cmd(&hci_read_local_name);
1237             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1238             break;
1239 
1240 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1241         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1242             hci_state_reset();
1243             // prepare reset if command complete not received in 100ms
1244             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1245             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1246             btstack_run_loop_add_timer(&hci_stack->timeout);
1247             // send command
1248             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1249             hci_send_cmd(&hci_reset);
1250             break;
1251         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1252             hci_state_reset();
1253             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1254             hci_send_cmd(&hci_reset);
1255             break;
1256         case HCI_INIT_SEND_BAUD_CHANGE: {
1257             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1258             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1259             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1260             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1261             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1262             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1263             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1264             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1265                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1266                 btstack_run_loop_add_timer(&hci_stack->timeout);
1267             }
1268             break;
1269         }
1270         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1271             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1272             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1273             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1274             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1275             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1276             break;
1277         }
1278         case HCI_INIT_CUSTOM_INIT:
1279             // Custom initialization
1280             if (hci_stack->chipset && hci_stack->chipset->next_command){
1281                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1282                 int send_cmd = 0;
1283                 switch (hci_stack->chipset_result){
1284                     case BTSTACK_CHIPSET_VALID_COMMAND:
1285                         send_cmd = 1;
1286                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1287                         break;
1288                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1289                         send_cmd = 1;
1290                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1291                         log_info("CSR Warm Boot");
1292                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1293                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1294                         btstack_run_loop_add_timer(&hci_stack->timeout);
1295                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1296                             && hci_stack->config
1297                             && hci_stack->chipset
1298                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1299                             && hci_stack->hci_transport->set_baudrate
1300                             && hci_transport_uart_get_main_baud_rate()){
1301                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1302                         } else {
1303                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1304                         }
1305                         break;
1306                     default:
1307                         break;
1308                 }
1309 
1310                 if (send_cmd){
1311                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1312                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1313                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1314                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1315                     break;
1316                 }
1317                 log_info("Init script done");
1318 
1319                 // Init script download on Broadcom chipsets causes:
1320                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1321                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1322                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1323 
1324                     // - baud rate to reset, restore UART baud rate if needed
1325                     int need_baud_change = hci_stack->config
1326                         && hci_stack->chipset
1327                         && hci_stack->chipset->set_baudrate_command
1328                         && hci_stack->hci_transport->set_baudrate
1329                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1330                     if (need_baud_change) {
1331                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1332                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1333                         hci_stack->hci_transport->set_baudrate(baud_rate);
1334                     }
1335 
1336                     uint16_t bcm_delay_ms = 300;
1337                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1338                     //   -> Work around: wait here.
1339                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1340                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1341                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1342                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1343                     btstack_run_loop_add_timer(&hci_stack->timeout);
1344                     break;
1345                 }
1346             }
1347             // otherwise continue
1348             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1349             hci_send_cmd(&hci_read_local_supported_commands);
1350             break;
1351         case HCI_INIT_SET_BD_ADDR:
1352             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1353             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1354             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1355             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1356             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1357             break;
1358 #endif
1359 
1360         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1361             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1362             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1363             hci_send_cmd(&hci_read_local_supported_commands);
1364             break;
1365         case HCI_INIT_READ_BD_ADDR:
1366             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1367             hci_send_cmd(&hci_read_bd_addr);
1368             break;
1369         case HCI_INIT_READ_BUFFER_SIZE:
1370             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1371             hci_send_cmd(&hci_read_buffer_size);
1372             break;
1373         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1374             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1375             hci_send_cmd(&hci_read_local_supported_features);
1376             break;
1377 
1378 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1379         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1380             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1381             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1382             break;
1383         case HCI_INIT_HOST_BUFFER_SIZE:
1384             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1385             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1386                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1387             break;
1388 #endif
1389 
1390         case HCI_INIT_SET_EVENT_MASK:
1391             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1392             if (hci_le_supported()){
1393                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1394             } else {
1395                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1396                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1397             }
1398             break;
1399 
1400 #ifdef ENABLE_CLASSIC
1401         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1403             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1404             break;
1405         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1407             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1408             break;
1409         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1410             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1411             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1412             break;
1413         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1414             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1415             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1416             break;
1417         case HCI_INIT_WRITE_LOCAL_NAME: {
1418             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1419             hci_reserve_packet_buffer();
1420             uint8_t * packet = hci_stack->hci_packet_buffer;
1421             // construct HCI Command and send
1422             uint16_t opcode = hci_write_local_name.opcode;
1423             hci_stack->last_cmd_opcode = opcode;
1424             packet[0] = opcode & 0xff;
1425             packet[1] = opcode >> 8;
1426             packet[2] = DEVICE_NAME_LEN;
1427             memset(&packet[3], 0, DEVICE_NAME_LEN);
1428             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1429             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1430             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1431             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1432             // expand '00:00:00:00:00:00' in name with bd_addr
1433             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1434             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1435             break;
1436         }
1437         case HCI_INIT_WRITE_EIR_DATA: {
1438             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1439             hci_reserve_packet_buffer();
1440             uint8_t * packet = hci_stack->hci_packet_buffer;
1441             // construct HCI Command in-place and send
1442             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1443             hci_stack->last_cmd_opcode = opcode;
1444             uint16_t offset = 0;
1445             packet[offset++] = opcode & 0xff;
1446             packet[offset++] = opcode >> 8;
1447             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1448             packet[offset++] = 0;  // FEC not required
1449             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1450             if (hci_stack->eir_data){
1451                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1452                 ad_context_t context;
1453                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1454                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1455                     uint8_t size        = ad_iterator_get_data_len(&context);
1456                     const uint8_t *data = ad_iterator_get_data(&context);
1457                     // copy item
1458                     packet[offset++] = size + 1;
1459                     packet[offset++] = data_type;
1460                     memcpy(&packet[offset], data, size);
1461                     // update name item
1462                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1463                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1464                     }
1465                     offset += size;
1466                 }
1467             } else {
1468                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1469                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1470                 packet[offset++] = bytes_to_copy + 1;
1471                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1472                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1473                 // expand '00:00:00:00:00:00' in name with bd_addr
1474                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1475             }
1476             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1477             break;
1478         }
1479         case HCI_INIT_WRITE_INQUIRY_MODE:
1480             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1481             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1482             break;
1483         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1484             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1485 			hci_stack->secure_connections_active = true;
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1487             break;
1488         case HCI_INIT_WRITE_SCAN_ENABLE:
1489             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1490             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1491             break;
1492         // only sent if ENABLE_SCO_OVER_HCI is defined
1493         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1494             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1495             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1496             break;
1497         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1498             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1499             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1500             break;
1501         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1502         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1503             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1504 #ifdef ENABLE_SCO_OVER_HCI
1505             log_info("BCM: Route SCO data via HCI transport");
1506             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1507 #endif
1508 #ifdef ENABLE_SCO_OVER_PCM
1509             log_info("BCM: Route SCO data via PCM interface");
1510             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 4, 0, 1, 1);
1511 #endif
1512             break;
1513 
1514 #endif
1515 #ifdef ENABLE_BLE
1516         // LE INIT
1517         case HCI_INIT_LE_READ_BUFFER_SIZE:
1518             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1519             hci_send_cmd(&hci_le_read_buffer_size);
1520             break;
1521         case HCI_INIT_LE_SET_EVENT_MASK:
1522             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1523             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1524             break;
1525         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1526             // LE Supported Host = 1, Simultaneous Host = 0
1527             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1528             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1529             break;
1530 #endif
1531 
1532 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1533         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1534             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1535             hci_send_cmd(&hci_le_read_maximum_data_length);
1536             break;
1537         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1538             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1539             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1540             break;
1541 #endif
1542 
1543 #ifdef ENABLE_LE_CENTRAL
1544         case HCI_INIT_READ_WHITE_LIST_SIZE:
1545             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1546             hci_send_cmd(&hci_le_read_white_list_size);
1547             break;
1548         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1549             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1550             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);
1551             break;
1552 #endif
1553         default:
1554             return;
1555     }
1556 }
1557 
1558 static void hci_init_done(void){
1559     // done. tell the app
1560     log_info("hci_init_done -> HCI_STATE_WORKING");
1561     hci_stack->state = HCI_STATE_WORKING;
1562     hci_emit_state();
1563     hci_run();
1564 }
1565 
1566 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1567     bool command_completed = false;
1568     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1569         uint16_t opcode = little_endian_read_16(packet,3);
1570         if (opcode == hci_stack->last_cmd_opcode){
1571             command_completed = true;
1572             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1573         } else {
1574             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1575         }
1576     }
1577 
1578     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1579         uint8_t  status = packet[2];
1580         uint16_t opcode = little_endian_read_16(packet,4);
1581         if (opcode == hci_stack->last_cmd_opcode){
1582             if (status){
1583                 command_completed = true;
1584                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1585             } else {
1586                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1587             }
1588         } else {
1589             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1590         }
1591     }
1592 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1593     // Vendor == CSR
1594     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1595         // TODO: track actual command
1596         command_completed = true;
1597     }
1598 
1599     // Vendor == Toshiba
1600     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1601         // TODO: track actual command
1602         command_completed = true;
1603         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1604         hci_stack->num_cmd_packets = 1;
1605     }
1606 #endif
1607 
1608     return command_completed;
1609 }
1610 
1611 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1612 
1613     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1614 
1615     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1616 
1617 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1618 
1619     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1620     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1621     //
1622     // HCI Reset
1623     // Timeout 100 ms
1624     // HCI Reset
1625     // Command Complete Reset
1626     // HCI Read Local Version Information
1627     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1628     // hang...
1629     //
1630     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1631     if (!command_completed
1632             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1633             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1634 
1635         uint16_t opcode = little_endian_read_16(packet,3);
1636         if (opcode == hci_reset.opcode){
1637             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1638             return;
1639         }
1640     }
1641 
1642     // CSR & H5
1643     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1644     if (!command_completed
1645             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1646             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1647 
1648         uint16_t opcode = little_endian_read_16(packet,3);
1649         if (opcode == hci_reset.opcode){
1650             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1651             return;
1652         }
1653     }
1654 
1655     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1656     // fix: Correct substate and behave as command below
1657     if (command_completed){
1658         switch (hci_stack->substate){
1659             case HCI_INIT_SEND_RESET:
1660                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1661                 break;
1662             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1663                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1664                 break;
1665             default:
1666                 break;
1667         }
1668     }
1669 
1670 #endif
1671 
1672     if (!command_completed) return;
1673 
1674     bool need_baud_change = false;
1675     bool need_addr_change = false;
1676 
1677 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1678     need_baud_change = hci_stack->config
1679                         && hci_stack->chipset
1680                         && hci_stack->chipset->set_baudrate_command
1681                         && hci_stack->hci_transport->set_baudrate
1682                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1683 
1684     need_addr_change = hci_stack->custom_bd_addr_set
1685                         && hci_stack->chipset
1686                         && hci_stack->chipset->set_bd_addr_command;
1687 #endif
1688 
1689     switch(hci_stack->substate){
1690 
1691 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1692         case HCI_INIT_SEND_RESET:
1693             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1694             // fix: just correct substate and behave as command below
1695             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1696             btstack_run_loop_remove_timer(&hci_stack->timeout);
1697             break;
1698         case HCI_INIT_W4_SEND_RESET:
1699             btstack_run_loop_remove_timer(&hci_stack->timeout);
1700             break;
1701         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1702             log_info("Received local name, need baud change %d", (int) need_baud_change);
1703             if (need_baud_change){
1704                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1705                 return;
1706             }
1707             // skip baud change
1708             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1709             return;
1710         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1711             // for STLC2500D, baud rate change already happened.
1712             // for others, baud rate gets changed now
1713             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1714                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1715                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1716                 hci_stack->hci_transport->set_baudrate(baud_rate);
1717             }
1718             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1719             return;
1720         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1721             btstack_run_loop_remove_timer(&hci_stack->timeout);
1722             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1723             return;
1724         case HCI_INIT_W4_CUSTOM_INIT:
1725             // repeat custom init
1726             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1727             return;
1728 #else
1729         case HCI_INIT_W4_SEND_RESET:
1730             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1731             return ;
1732 #endif
1733 
1734         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1735             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1736               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1737                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1738                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1739                 return;
1740             }
1741             if (need_addr_change){
1742                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1743                 return;
1744             }
1745             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1746             return;
1747 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1748         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1749             if (need_baud_change){
1750                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1751                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1752                 hci_stack->hci_transport->set_baudrate(baud_rate);
1753             }
1754             if (need_addr_change){
1755                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1756                 return;
1757             }
1758             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1759             return;
1760         case HCI_INIT_W4_SET_BD_ADDR:
1761             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1762             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1763             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1764                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1765                 return;
1766             }
1767             // skipping st warm boot
1768             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1769             return;
1770         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1771             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1772             return;
1773 #endif
1774         case HCI_INIT_W4_READ_BD_ADDR:
1775             // only read buffer size if supported
1776             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1777                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1778                 return;
1779             }
1780             // skipping read buffer size
1781             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1782             return;
1783         case HCI_INIT_W4_SET_EVENT_MASK:
1784             // skip Classic init commands for LE only chipsets
1785             if (!hci_classic_supported()){
1786 #ifdef ENABLE_BLE
1787                 if (hci_le_supported()){
1788                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1789                     return;
1790                 }
1791 #endif
1792                 log_error("Neither BR/EDR nor LE supported");
1793                 hci_init_done();
1794                 return;
1795             }
1796             if (!gap_ssp_supported()){
1797                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1798                 return;
1799             }
1800             break;
1801 #ifdef ENABLE_BLE
1802         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1803             // skip write le host if not supported (e.g. on LE only EM9301)
1804             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1805             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1806             return;
1807 
1808 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1809         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1810             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1811             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1812                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1813                 return;
1814             }
1815             // explicit fall through to reduce repetitions
1816 
1817 #ifdef ENABLE_LE_CENTRAL
1818             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1819 #else
1820             hci_init_done();
1821 #endif
1822             return;
1823 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1824 
1825 #endif  /* ENABLE_BLE */
1826 
1827         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1828             // skip write secure connections host support if not supported or disabled
1829             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1830                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1831                 return;
1832             }
1833             break;
1834 
1835 #ifdef ENABLE_SCO_OVER_HCI
1836         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1837             // skip write synchronous flow control if not supported
1838             if (hci_stack->local_supported_commands[0] & 0x04) break;
1839             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1840 
1841             /* fall through */
1842 
1843         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1844             // skip write default erroneous data reporting if not supported
1845             if (hci_stack->local_supported_commands[0] & 0x08) break;
1846             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1847 
1848             /* fall through */
1849 
1850         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1851             // skip bcm set sco pcm config on non-Broadcom chipsets
1852             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1853             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1854 
1855             /* fall through */
1856 
1857         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1858             if (!hci_le_supported()){
1859                 // SKIP LE init for Classic only configuration
1860                 hci_init_done();
1861                 return;
1862             }
1863             break;
1864 
1865 #else /* !ENABLE_SCO_OVER_HCI */
1866 
1867         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1868 #ifdef ENABLE_SCO_OVER_PCM
1869             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1870                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1871                 return;
1872             }
1873 #endif
1874             /* fall through */
1875 
1876         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1877 #ifdef ENABLE_BLE
1878             if (hci_le_supported()){
1879                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1880                 return;
1881             }
1882 #endif
1883             // SKIP LE init for Classic only configuration
1884             hci_init_done();
1885             return;
1886 #endif /* ENABLE_SCO_OVER_HCI */
1887 
1888 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1889 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1890         // Response to command before init done state -> init done
1891         case (HCI_INIT_DONE-1):
1892             hci_init_done();
1893             return;
1894 #endif
1895 
1896         default:
1897             break;
1898     }
1899     hci_initializing_next_state();
1900 }
1901 
1902 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1903     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1904     bd_addr_t bd_address;
1905     (void)memcpy(&bd_address, conn->address, 6);
1906 
1907 #ifdef ENABLE_CLASSIC
1908     // cache needed data
1909     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1910 #endif
1911 
1912     // connection failed, remove entry
1913     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1914     btstack_memory_hci_connection_free( conn );
1915 
1916 #ifdef ENABLE_CLASSIC
1917     // notify client if dedicated bonding
1918     if (notify_dedicated_bonding_failed){
1919         log_info("hci notify_dedicated_bonding_failed");
1920         hci_emit_dedicated_bonding_result(bd_address, status);
1921     }
1922 
1923     // if authentication error, also delete link key
1924     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1925         gap_drop_link_key_for_bd_addr(bd_address);
1926     }
1927 #else
1928     UNUSED(status);
1929 #endif
1930 }
1931 
1932 #ifdef ENABLE_CLASSIC
1933 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1934     // SSP Controller
1935     if (features[6] & (1 << 3)){
1936         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1937     }
1938     // eSCO
1939     if (features[3] & (1<<7)){
1940         conn->remote_supported_features[0] |= 1;
1941     }
1942     // Extended features
1943     if (features[7] & (1<<7)){
1944         conn->remote_supported_features[0] |= 2;
1945     }
1946 }
1947 
1948 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1949     // SSP Host
1950     if (features[0] & (1 << 0)){
1951         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1952     }
1953     // SC Host
1954     if (features[0] & (1 << 3)){
1955         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1956     }
1957 }
1958 
1959 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1960     // SC Controller
1961     if (features[1] & (1 << 0)){
1962         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1963     }
1964 }
1965 
1966 static void hci_handle_remote_features_received(hci_connection_t * conn){
1967     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1968     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1969     if (conn->bonding_flags & BONDING_DEDICATED){
1970         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1971     }
1972 }
1973 #endif
1974 
1975 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1976     // handle BT initialization
1977     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1978         hci_initializing_event_handler(packet, size);
1979     }
1980 
1981     // help with BT sleep
1982     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1983         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1984         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1985         hci_initializing_next_state();
1986     }
1987 }
1988 
1989 #ifdef ENABLE_CLASSIC
1990 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1991     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1992     conn->encryption_key_size = encryption_key_size;
1993 
1994     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1995         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1996         return;
1997     }
1998 
1999     // Request Authentication if not already done
2000     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2001     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2002 }
2003 #endif
2004 
2005 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2006     UNUSED(size);
2007 
2008     uint16_t manufacturer;
2009 #ifdef ENABLE_CLASSIC
2010     hci_con_handle_t handle;
2011     hci_connection_t * conn;
2012     uint8_t status;
2013 #endif
2014     // get num cmd packets - limit to 1 to reduce complexity
2015     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2016 
2017     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2018     switch (opcode){
2019         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2020             if (packet[5]) break;
2021             // terminate, name 248 chars
2022             packet[6+248] = 0;
2023             log_info("local name: %s", &packet[6]);
2024             break;
2025         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2026             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2027             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2028                 uint16_t acl_len = little_endian_read_16(packet, 6);
2029                 uint16_t sco_len = packet[8];
2030 
2031                 // determine usable ACL/SCO payload size
2032                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2033                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2034 
2035                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2036                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2037 
2038                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2039                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2040                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2041             }
2042             break;
2043         case HCI_OPCODE_HCI_READ_RSSI:
2044             if (packet[5] == ERROR_CODE_SUCCESS){
2045                 uint8_t event[5];
2046                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2047                 event[1] = 3;
2048                 (void)memcpy(&event[2], &packet[6], 3);
2049                 hci_emit_event(event, sizeof(event), 1);
2050             }
2051             break;
2052 #ifdef ENABLE_BLE
2053         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2054             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2055             hci_stack->le_acl_packets_total_num = packet[8];
2056             // determine usable ACL payload size
2057             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2058                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2059             }
2060             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2061             break;
2062 #endif
2063 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2064         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2065             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2066             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2067             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);
2068             break;
2069 #endif
2070 #ifdef ENABLE_LE_CENTRAL
2071         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2072             hci_stack->le_whitelist_capacity = packet[6];
2073             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2074             break;
2075 #endif
2076         case HCI_OPCODE_HCI_READ_BD_ADDR:
2077             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2078             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));
2079 #ifdef ENABLE_CLASSIC
2080             if (hci_stack->link_key_db){
2081                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2082             }
2083 #endif
2084             break;
2085 #ifdef ENABLE_CLASSIC
2086         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2087             hci_emit_discoverable_enabled(hci_stack->discoverable);
2088             break;
2089         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2090             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2091                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2092                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2093                 hci_emit_event(event, sizeof(event), 1);
2094             }
2095             break;
2096 #endif
2097         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2098             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2099 
2100 #ifdef ENABLE_CLASSIC
2101             // determine usable ACL packet types based on host buffer size and supported features
2102             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2103             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2104 #endif
2105             // Classic/LE
2106             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2107             break;
2108         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2109             manufacturer = little_endian_read_16(packet, 10);
2110             // map Cypress to Broadcom
2111             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2112                 log_info("Treat Cypress as Broadcom");
2113                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2114                 little_endian_store_16(packet, 10, manufacturer);
2115             }
2116             hci_stack->manufacturer = manufacturer;
2117             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2118             break;
2119         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2120             hci_stack->local_supported_commands[0] =
2121                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2122                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2123                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2124                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2125                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2126                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2127                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2128                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2129             hci_stack->local_supported_commands[1] =
2130                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2131                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2132                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u);   // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2133             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2134             break;
2135 #ifdef ENABLE_CLASSIC
2136         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2137             if (packet[5]) return;
2138             hci_stack->synchronous_flow_control_enabled = 1;
2139             break;
2140         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2141             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2142             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2143             conn   = hci_connection_for_handle(handle);
2144             if (conn != NULL) {
2145                 uint8_t key_size = 0;
2146                 if (status == 0){
2147                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2148                     log_info("Handle %04x key Size: %u", handle, key_size);
2149                 } else {
2150                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2151                 }
2152                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2153             }
2154             break;
2155 #endif
2156         default:
2157             break;
2158     }
2159 }
2160 
2161 #ifdef ENABLE_BLE
2162 static void event_handle_le_connection_complete(const uint8_t * packet){
2163 	bd_addr_t addr;
2164 	bd_addr_type_t addr_type;
2165 	hci_connection_t * conn;
2166 
2167 	// Connection management
2168 	reverse_bd_addr(&packet[8], addr);
2169 	addr_type = (bd_addr_type_t)packet[7];
2170 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2171 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2172 
2173 #ifdef ENABLE_LE_CENTRAL
2174 	// handle error: error is reported only to the initiator -> outgoing connection
2175 	if (packet[3]){
2176 
2177 		// handle cancelled outgoing connection
2178 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2179 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2180 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2181 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2182 			// whitelist connect
2183 			if (hci_is_le_connection_type(addr_type)){
2184 				hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2185 			}
2186 			// get outgoing connection conn struct for direct connect
2187 			conn = gap_get_outgoing_connection();
2188 		}
2189 
2190 		// outgoing le connection establishment is done
2191 		if (conn){
2192 			// remove entry
2193 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2194 			btstack_memory_hci_connection_free( conn );
2195 		}
2196 		return;
2197 	}
2198 #endif
2199 
2200 	// on success, both hosts receive connection complete event
2201 	if (packet[6] == HCI_ROLE_MASTER){
2202 #ifdef ENABLE_LE_CENTRAL
2203 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2204 		// note: no hci_connection_t object exists yet for connect with whitelist
2205 		if (hci_is_le_connection_type(addr_type)){
2206 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2207 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2208 		}
2209 #endif
2210 	} else {
2211 #ifdef ENABLE_LE_PERIPHERAL
2212 		// if we're slave, it was an incoming connection, advertisements have stopped
2213 		hci_stack->le_advertisements_active = false;
2214 #endif
2215 	}
2216 
2217 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2218 	if (!conn){
2219 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2220 	}
2221 
2222 	// no memory, sorry.
2223 	if (!conn){
2224 		return;
2225 	}
2226 
2227 	conn->state = OPEN;
2228 	conn->role  = packet[6];
2229 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2230 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2231 
2232 #ifdef ENABLE_LE_PERIPHERAL
2233 	if (packet[6] == HCI_ROLE_SLAVE){
2234 		hci_update_advertisements_enabled_for_current_roles();
2235 	}
2236 #endif
2237 
2238     // init unenhanced att bearer mtu
2239     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2240     conn->att_connection.mtu_exchanged = false;
2241 
2242     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2243 
2244 	// restart timer
2245 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2246 	// btstack_run_loop_add_timer(&conn->timeout);
2247 
2248 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2249 
2250 	hci_emit_nr_connections_changed();
2251 }
2252 #endif
2253 
2254 static void event_handler(uint8_t *packet, uint16_t size){
2255 
2256     uint16_t event_length = packet[1];
2257 
2258     // assert packet is complete
2259     if (size != (event_length + 2u)){
2260         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2261         return;
2262     }
2263 
2264     bd_addr_type_t addr_type;
2265     hci_con_handle_t handle;
2266     hci_connection_t * conn;
2267     int i;
2268     int create_connection_cmd;
2269 
2270 #ifdef ENABLE_CLASSIC
2271     hci_link_type_t link_type;
2272     bd_addr_t addr;
2273 #endif
2274 
2275     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2276 
2277     switch (hci_event_packet_get_type(packet)) {
2278 
2279         case HCI_EVENT_COMMAND_COMPLETE:
2280             handle_command_complete_event(packet, size);
2281             break;
2282 
2283         case HCI_EVENT_COMMAND_STATUS:
2284             // get num cmd packets - limit to 1 to reduce complexity
2285             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2286 
2287             // check command status to detected failed outgoing connections
2288             create_connection_cmd = 0;
2289 #ifdef ENABLE_CLASSIC
2290             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2291                 create_connection_cmd = 1;
2292             }
2293 #endif
2294 #ifdef ENABLE_LE_CENTRAL
2295             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2296                 create_connection_cmd = 1;
2297             }
2298 #endif
2299             if (create_connection_cmd) {
2300                 uint8_t status = hci_event_command_status_get_status(packet);
2301                 addr_type = hci_stack->outgoing_addr_type;
2302                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2303                 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);
2304 
2305                 // reset outgoing address info
2306                 memset(hci_stack->outgoing_addr, 0, 6);
2307                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2308 
2309                 // on error
2310                 if (status != ERROR_CODE_SUCCESS){
2311 #ifdef ENABLE_LE_CENTRAL
2312                     if (hci_is_le_connection_type(addr_type)){
2313                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2314                     }
2315 #endif
2316                     // error => outgoing connection failed
2317                     if (conn != NULL){
2318                         hci_handle_connection_failed(conn, status);
2319                     }
2320                 }
2321             }
2322             break;
2323 
2324         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2325             if (size < 3) return;
2326             uint16_t num_handles = packet[2];
2327             if (size != (3u + num_handles * 4u)) return;
2328             uint16_t offset = 3;
2329             for (i=0; i<num_handles;i++){
2330                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2331                 offset += 2u;
2332                 uint16_t num_packets = little_endian_read_16(packet, offset);
2333                 offset += 2u;
2334 
2335                 conn = hci_connection_for_handle(handle);
2336                 if (!conn){
2337                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2338                     continue;
2339                 }
2340 
2341                 if (conn->num_packets_sent >= num_packets){
2342                     conn->num_packets_sent -= num_packets;
2343                 } else {
2344                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2345                     conn->num_packets_sent = 0;
2346                 }
2347                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2348 
2349 #ifdef ENABLE_CLASSIC
2350                 // For SCO, we do the can_send_now_check here
2351                 hci_notify_if_sco_can_send_now();
2352 #endif
2353             }
2354             break;
2355         }
2356 
2357 #ifdef ENABLE_CLASSIC
2358         case HCI_EVENT_INQUIRY_COMPLETE:
2359             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2360                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2361                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2362                 hci_emit_event(event, sizeof(event), 1);
2363             }
2364             break;
2365         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2366             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2367                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2368             }
2369             break;
2370         case HCI_EVENT_CONNECTION_REQUEST:
2371             reverse_bd_addr(&packet[2], addr);
2372             link_type = (hci_link_type_t) packet[11];
2373             if (hci_stack->gap_classic_accept_callback != NULL){
2374                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2375                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2376                     bd_addr_copy(hci_stack->decline_addr, addr);
2377                     break;
2378                 }
2379             }
2380 
2381             // TODO: eval COD 8-10
2382             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2383             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2384             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2385             if (!conn) {
2386                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2387             }
2388             if (!conn) {
2389                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2390                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2391                 bd_addr_copy(hci_stack->decline_addr, addr);
2392                 break;
2393             }
2394             conn->role  = HCI_ROLE_SLAVE;
2395             conn->state = RECEIVED_CONNECTION_REQUEST;
2396             // store info about eSCO
2397             if (link_type == HCI_LINK_TYPE_ESCO){
2398                 conn->remote_supported_features[0] |= 1;
2399             }
2400             hci_run();
2401             break;
2402 
2403         case HCI_EVENT_CONNECTION_COMPLETE:
2404             // Connection management
2405             reverse_bd_addr(&packet[5], addr);
2406             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2407             addr_type = BD_ADDR_TYPE_ACL;
2408             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2409             if (conn) {
2410                 if (!packet[2]){
2411                     conn->state = OPEN;
2412                     conn->con_handle = little_endian_read_16(packet, 3);
2413 
2414                     // queue get remote feature
2415                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2416 
2417                     // queue set supervision timeout if we're master
2418                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2419                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2420                     }
2421 
2422                     // restart timer
2423                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2424                     btstack_run_loop_add_timer(&conn->timeout);
2425 
2426                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2427 
2428                     hci_emit_nr_connections_changed();
2429                 } else {
2430                     // connection failed
2431                     hci_handle_connection_failed(conn, packet[2]);
2432                 }
2433             }
2434             break;
2435 
2436         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2437             reverse_bd_addr(&packet[5], addr);
2438             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2439             if (packet[2]){
2440                 // connection failed
2441                 break;
2442             }
2443             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2444             if (!conn) {
2445                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2446             }
2447             if (!conn) {
2448                 break;
2449             }
2450             conn->state = OPEN;
2451             conn->con_handle = little_endian_read_16(packet, 3);
2452 
2453 #ifdef ENABLE_SCO_OVER_HCI
2454             // update SCO
2455             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2456                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2457             }
2458             // trigger can send now
2459             if (hci_have_usb_transport()){
2460                 hci_stack->sco_can_send_now = 1;
2461             }
2462 #endif
2463             break;
2464 
2465         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2466             handle = little_endian_read_16(packet, 3);
2467             conn = hci_connection_for_handle(handle);
2468             if (!conn) break;
2469             if (!packet[2]){
2470                 const uint8_t * features = &packet[5];
2471                 hci_handle_remote_features_page_0(conn, features);
2472 
2473                 // read extended features if possible
2474                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2475                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2476                     break;
2477                 }
2478             }
2479             hci_handle_remote_features_received(conn);
2480             break;
2481 
2482         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2483             handle = little_endian_read_16(packet, 3);
2484             conn = hci_connection_for_handle(handle);
2485             if (!conn) break;
2486             // status = ok, page = 1
2487             if (!packet[2]) {
2488                 uint8_t page_number = packet[5];
2489                 uint8_t maximum_page_number = packet[6];
2490                 const uint8_t * features = &packet[7];
2491                 bool done = false;
2492                 switch (page_number){
2493                     case 1:
2494                         hci_handle_remote_features_page_1(conn, features);
2495                         if (maximum_page_number >= 2){
2496                             // get Secure Connections (Controller) from Page 2 if available
2497                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2498                         } else {
2499                             // otherwise, assume SC (Controller) == SC (Host)
2500                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2501                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2502                             }
2503                             done = true;
2504                         }
2505                         break;
2506                     case 2:
2507                         hci_handle_remote_features_page_2(conn, features);
2508                         done = true;
2509                         break;
2510                     default:
2511                         break;
2512                 }
2513                 if (!done) break;
2514             }
2515             hci_handle_remote_features_received(conn);
2516             break;
2517 
2518         case HCI_EVENT_LINK_KEY_REQUEST:
2519             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2520             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2521             // request handled by hci_run()
2522             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2523             break;
2524 
2525         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2526             reverse_bd_addr(&packet[2], addr);
2527             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2528             if (!conn) break;
2529             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2530             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2531             // Change Connection Encryption keeps link key type
2532             if (link_key_type != CHANGED_COMBINATION_KEY){
2533                 conn->link_key_type = link_key_type;
2534             }
2535             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2536             // still forward event to allow dismiss of pairing dialog
2537             break;
2538         }
2539 
2540         case HCI_EVENT_PIN_CODE_REQUEST:
2541             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2542             // non-bondable mode: pin code negative reply will be sent
2543             if (!hci_stack->bondable){
2544                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2545                 hci_run();
2546                 return;
2547             }
2548             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2549             if (!hci_stack->link_key_db) break;
2550             hci_event_pin_code_request_get_bd_addr(packet, addr);
2551             hci_stack->link_key_db->delete_link_key(addr);
2552             break;
2553 
2554         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2555             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2556             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2557             break;
2558 
2559         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2560             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2561             if (!hci_stack->ssp_auto_accept) break;
2562             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2563             break;
2564 
2565         case HCI_EVENT_USER_PASSKEY_REQUEST:
2566             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2567             if (!hci_stack->ssp_auto_accept) break;
2568             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2569             break;
2570         case HCI_EVENT_MODE_CHANGE:
2571             handle = hci_event_mode_change_get_handle(packet);
2572             conn = hci_connection_for_handle(handle);
2573             if (!conn) break;
2574             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2575             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2576             break;
2577 #endif
2578 
2579         case HCI_EVENT_ENCRYPTION_CHANGE:
2580             handle = hci_event_encryption_change_get_connection_handle(packet);
2581             conn = hci_connection_for_handle(handle);
2582             if (!conn) break;
2583             if (hci_event_encryption_change_get_status(packet) == 0u) {
2584                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2585                 if (encryption_enabled){
2586                     if (hci_is_le_connection(conn)){
2587                         // For LE, we accept connection as encrypted
2588                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2589                     }
2590 #ifdef ENABLE_CLASSIC
2591                     else {
2592                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2593                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2594                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2595                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2596                             log_info("SC during pairing, but only E0 now -> abort");
2597                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2598                             break;
2599                         }
2600 
2601                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2602                         if (connected_uses_aes_ccm){
2603                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2604                         }
2605 
2606                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2607                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2608                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2609                         } else {
2610                             // if not, pretend everything is perfect
2611                             hci_handle_read_encryption_key_size_complete(conn, 16);
2612                         }
2613                     }
2614 #endif
2615                 } else {
2616                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2617                 }
2618             }
2619 
2620             break;
2621 
2622 #ifdef ENABLE_CLASSIC
2623         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2624             handle = hci_event_authentication_complete_get_connection_handle(packet);
2625             conn = hci_connection_for_handle(handle);
2626             if (!conn) break;
2627 
2628             // ignore authentication event if we didn't request it
2629             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2630 
2631             // dedicated bonding: send result and disconnect
2632             if (conn->bonding_flags & BONDING_DEDICATED){
2633                 conn->bonding_flags &= ~BONDING_DEDICATED;
2634                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2635                 conn->bonding_status = packet[2];
2636                 break;
2637             }
2638 
2639             // authenticated only if auth status == 0
2640             if (hci_event_authentication_complete_get_status(packet) == 0){
2641                 // authenticated
2642                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2643 
2644                 // If link key sufficient for requested security and not already encrypted, start encryption
2645                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2646                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2647                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2648                     break;
2649                 }
2650             }
2651 
2652             // emit updated security level
2653             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2654             break;
2655 #endif
2656 
2657         // HCI_EVENT_DISCONNECTION_COMPLETE
2658         // has been split, to first notify stack before shutting connection down
2659         // see end of function, too.
2660         case HCI_EVENT_DISCONNECTION_COMPLETE:
2661             if (packet[2]) break;   // status != 0
2662             handle = little_endian_read_16(packet, 3);
2663             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2664             if (hci_stack->acl_fragmentation_total_size > 0u) {
2665                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2666                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2667                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2668                     hci_stack->acl_fragmentation_total_size = 0;
2669                     hci_stack->acl_fragmentation_pos = 0;
2670                     if (release_buffer){
2671                         hci_release_packet_buffer();
2672                     }
2673                 }
2674             }
2675 
2676             conn = hci_connection_for_handle(handle);
2677             if (!conn) break;
2678             // mark connection for shutdown
2679             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2680 
2681             // emit dedicatd bonding event
2682             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2683                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2684             }
2685 
2686 #ifdef ENABLE_BLE
2687 #ifdef ENABLE_LE_PERIPHERAL
2688             // re-enable advertisements for le connections if active
2689             if (hci_is_le_connection(conn)){
2690                 hci_update_advertisements_enabled_for_current_roles();
2691             }
2692 #endif
2693 #endif
2694             break;
2695 
2696         case HCI_EVENT_HARDWARE_ERROR:
2697             log_error("Hardware Error: 0x%02x", packet[2]);
2698             if (hci_stack->hardware_error_callback){
2699                 (*hci_stack->hardware_error_callback)(packet[2]);
2700             } else {
2701                 // if no special requests, just reboot stack
2702                 hci_power_control_off();
2703                 hci_power_control_on();
2704             }
2705             break;
2706 
2707 #ifdef ENABLE_CLASSIC
2708         case HCI_EVENT_ROLE_CHANGE:
2709             if (packet[2]) break;   // status != 0
2710             reverse_bd_addr(&packet[3], addr);
2711             addr_type = BD_ADDR_TYPE_ACL;
2712             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2713             if (!conn) break;
2714             conn->role = packet[9];
2715             break;
2716 #endif
2717 
2718         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2719             // release packet buffer only for asynchronous transport and if there are not further fragements
2720             if (hci_transport_synchronous()) {
2721                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2722                 return; // instead of break: to avoid re-entering hci_run()
2723             }
2724             hci_stack->acl_fragmentation_tx_active = 0;
2725             if (hci_stack->acl_fragmentation_total_size) break;
2726             hci_release_packet_buffer();
2727 
2728             // L2CAP receives this event via the hci_emit_event below
2729 
2730 #ifdef ENABLE_CLASSIC
2731             // For SCO, we do the can_send_now_check here
2732             hci_notify_if_sco_can_send_now();
2733 #endif
2734             break;
2735 
2736 #ifdef ENABLE_CLASSIC
2737         case HCI_EVENT_SCO_CAN_SEND_NOW:
2738             // For SCO, we do the can_send_now_check here
2739             hci_stack->sco_can_send_now = 1;
2740             hci_notify_if_sco_can_send_now();
2741             return;
2742 
2743         // explode inquriy results for easier consumption
2744         case HCI_EVENT_INQUIRY_RESULT:
2745         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2746         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2747             gap_inquiry_explode(packet, size);
2748             break;
2749 #endif
2750 
2751 #ifdef ENABLE_BLE
2752         case HCI_EVENT_LE_META:
2753             switch (packet[2]){
2754 #ifdef ENABLE_LE_CENTRAL
2755                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2756                     // log_info("advertising report received");
2757                     if (!hci_stack->le_scanning_enabled) break;
2758                     le_handle_advertisement_report(packet, size);
2759                     break;
2760 #endif
2761                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2762 					event_handle_le_connection_complete(packet);
2763                     break;
2764 
2765                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2766                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2767                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2768                     conn = hci_connection_for_handle(handle);
2769                     if (!conn) break;
2770                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2771                     break;
2772 
2773                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2774                     // connection
2775                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2776                     conn = hci_connection_for_handle(handle);
2777                     if (conn) {
2778                         // read arguments
2779                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2780                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2781                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2782                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2783 
2784                         // validate against current connection parameter range
2785                         le_connection_parameter_range_t existing_range;
2786                         gap_get_connection_parameter_range(&existing_range);
2787                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2788                         if (update_parameter){
2789                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2790                             conn->le_conn_interval_min = le_conn_interval_min;
2791                             conn->le_conn_interval_max = le_conn_interval_max;
2792                             conn->le_conn_latency = le_conn_latency;
2793                             conn->le_supervision_timeout = le_supervision_timeout;
2794                         } else {
2795                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
2796                         }
2797                     }
2798                     break;
2799 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2800                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2801                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2802                     conn = hci_connection_for_handle(handle);
2803                     if (conn) {
2804                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2805                     }
2806                     break;
2807 #endif
2808                 default:
2809                     break;
2810             }
2811             break;
2812 #endif
2813         case HCI_EVENT_VENDOR_SPECIFIC:
2814             // Vendor specific commands often create vendor specific event instead of num completed packets
2815             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2816             switch (hci_stack->manufacturer){
2817                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2818                     hci_stack->num_cmd_packets = 1;
2819                     break;
2820                 default:
2821                     break;
2822             }
2823             break;
2824         default:
2825             break;
2826     }
2827 
2828     handle_event_for_current_stack_state(packet, size);
2829 
2830     // notify upper stack
2831 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2832 
2833     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2834     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
2835 		handle = little_endian_read_16(packet, 3);
2836 		hci_connection_t * aConn = hci_connection_for_handle(handle);
2837 		// discard connection if app did not trigger a reconnect in the event handler
2838 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2839 			hci_shutdown_connection(aConn);
2840 		}
2841     }
2842 
2843 	// execute main loop
2844 	hci_run();
2845 }
2846 
2847 #ifdef ENABLE_CLASSIC
2848 
2849 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2850 static void sco_schedule_tx(hci_connection_t * conn);
2851 
2852 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2853     log_debug("SCO TX Timeout");
2854     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2855     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2856     if (!conn) return;
2857 
2858     // trigger send
2859     conn->sco_tx_ready = 1;
2860     // extra packet if CVSD but SCO buffer is too short
2861     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2862         conn->sco_tx_ready++;
2863     }
2864     hci_notify_if_sco_can_send_now();
2865 }
2866 
2867 
2868 #define SCO_TX_AFTER_RX_MS (6)
2869 
2870 static void sco_schedule_tx(hci_connection_t * conn){
2871 
2872     uint32_t now = btstack_run_loop_get_time_ms();
2873     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2874     int time_delta_ms = sco_tx_ms - now;
2875 
2876     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2877 
2878     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2879     btstack_run_loop_set_timer(timer, time_delta_ms);
2880     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2881     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2882     btstack_run_loop_add_timer(timer);
2883 }
2884 
2885 static void sco_handler(uint8_t * packet, uint16_t size){
2886     // lookup connection struct
2887     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2888     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2889     if (!conn) return;
2890 
2891     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2892     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2893         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2894             packet[2] = 0x3c;
2895             memmove(&packet[3], &packet[23], 63);
2896             size = 63;
2897         }
2898     }
2899 
2900     if (hci_have_usb_transport()){
2901         // Nothing to do
2902     } else {
2903         // 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);
2904         if (hci_stack->synchronous_flow_control_enabled == 0){
2905             uint32_t now = btstack_run_loop_get_time_ms();
2906 
2907             if (!conn->sco_rx_valid){
2908                 // ignore first 10 packets
2909                 conn->sco_rx_count++;
2910                 // log_debug("sco rx count %u", conn->sco_rx_count);
2911                 if (conn->sco_rx_count == 10) {
2912                     // use first timestamp as is and pretent it just started
2913                     conn->sco_rx_ms = now;
2914                     conn->sco_rx_valid = 1;
2915                     conn->sco_rx_count = 0;
2916                     sco_schedule_tx(conn);
2917                 }
2918             } else {
2919                 // track expected arrival timme
2920                 conn->sco_rx_count++;
2921                 conn->sco_rx_ms += 7;
2922                 int delta = (int32_t) (now - conn->sco_rx_ms);
2923                 if (delta > 0){
2924                     conn->sco_rx_ms++;
2925                 }
2926                 // log_debug("sco rx %u", conn->sco_rx_ms);
2927                 sco_schedule_tx(conn);
2928             }
2929         }
2930     }
2931     // deliver to app
2932     if (hci_stack->sco_packet_handler) {
2933         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2934     }
2935 
2936 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2937     conn->num_packets_completed++;
2938     hci_stack->host_completed_packets = 1;
2939     hci_run();
2940 #endif
2941 }
2942 #endif
2943 
2944 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2945     hci_dump_packet(packet_type, 1, packet, size);
2946     switch (packet_type) {
2947         case HCI_EVENT_PACKET:
2948             event_handler(packet, size);
2949             break;
2950         case HCI_ACL_DATA_PACKET:
2951             acl_handler(packet, size);
2952             break;
2953 #ifdef ENABLE_CLASSIC
2954         case HCI_SCO_DATA_PACKET:
2955             sco_handler(packet, size);
2956             break;
2957 #endif
2958         default:
2959             break;
2960     }
2961 }
2962 
2963 /**
2964  * @brief Add event packet handler.
2965  */
2966 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2967     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2968 }
2969 
2970 
2971 /** Register HCI packet handlers */
2972 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2973     hci_stack->acl_packet_handler = handler;
2974 }
2975 
2976 #ifdef ENABLE_CLASSIC
2977 /**
2978  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2979  */
2980 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2981     hci_stack->sco_packet_handler = handler;
2982 }
2983 #endif
2984 
2985 static void hci_state_reset(void){
2986     // no connections yet
2987     hci_stack->connections = NULL;
2988 
2989     // keep discoverable/connectable as this has been requested by the client(s)
2990     // hci_stack->discoverable = 0;
2991     // hci_stack->connectable = 0;
2992     // hci_stack->bondable = 1;
2993     // hci_stack->own_addr_type = 0;
2994 
2995     // buffer is free
2996     hci_stack->hci_packet_buffer_reserved = 0;
2997 
2998     // no pending cmds
2999     hci_stack->decline_reason = 0;
3000     hci_stack->new_scan_enable_value = 0xff;
3001 
3002     hci_stack->secure_connections_active = false;
3003 
3004     // LE
3005 #ifdef ENABLE_BLE
3006     memset(hci_stack->le_random_address, 0, 6);
3007     hci_stack->le_random_address_set = 0;
3008 #endif
3009 #ifdef ENABLE_LE_CENTRAL
3010     hci_stack->le_scanning_active  = 0;
3011     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3012     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3013     hci_stack->le_whitelist_capacity = 0;
3014 #endif
3015 }
3016 
3017 #ifdef ENABLE_CLASSIC
3018 /**
3019  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3020  */
3021 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3022     // store and open remote device db
3023     hci_stack->link_key_db = link_key_db;
3024     if (hci_stack->link_key_db) {
3025         hci_stack->link_key_db->open();
3026     }
3027 }
3028 #endif
3029 
3030 void hci_init(const hci_transport_t *transport, const void *config){
3031 
3032 #ifdef HAVE_MALLOC
3033     if (!hci_stack) {
3034         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3035     }
3036 #else
3037     hci_stack = &hci_stack_static;
3038 #endif
3039     memset(hci_stack, 0, sizeof(hci_stack_t));
3040 
3041     // reference to use transport layer implementation
3042     hci_stack->hci_transport = transport;
3043 
3044     // reference to used config
3045     hci_stack->config = config;
3046 
3047     // setup pointer for outgoing packet buffer
3048     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3049 
3050     // max acl payload size defined in config.h
3051     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3052 
3053     // register packet handlers with transport
3054     transport->register_packet_handler(&packet_handler);
3055 
3056     hci_stack->state = HCI_STATE_OFF;
3057 
3058     // class of device
3059     hci_stack->class_of_device = 0x007a020c; // Smartphone
3060 
3061     // bondable by default
3062     hci_stack->bondable = 1;
3063 
3064 #ifdef ENABLE_CLASSIC
3065     // classic name
3066     hci_stack->local_name = default_classic_name;
3067 
3068     // Master slave policy
3069     hci_stack->master_slave_policy = 1;
3070 
3071     // Allow Role Switch
3072     hci_stack->allow_role_switch = 1;
3073 
3074     // Default / minimum security level = 2
3075     hci_stack->gap_security_level = LEVEL_2;
3076 
3077     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3078     hci_stack->gap_required_encyrption_key_size = 7;
3079 #endif
3080 
3081     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3082     hci_stack->ssp_enable = 1;
3083     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3084     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3085     hci_stack->ssp_auto_accept = 1;
3086 
3087     // Secure Connections: enable (requires support from Controller)
3088     hci_stack->secure_connections_enable = true;
3089 
3090     // voice setting - signed 16 bit pcm data with CVSD over the air
3091     hci_stack->sco_voice_setting = 0x60;
3092 
3093 #ifdef ENABLE_LE_CENTRAL
3094     // connection parameter to use for outgoing connections
3095     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3096     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3097     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3098     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3099     hci_stack->le_connection_latency      = 4;         // 4
3100     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3101     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3102     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3103 
3104     // default LE Scanning
3105     hci_stack->le_scan_type     =   0x1; // active
3106     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3107     hci_stack->le_scan_window   =  0x30; //  30 ms
3108 #endif
3109 
3110 #ifdef ENABLE_LE_PERIPHERAL
3111     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3112 #endif
3113 
3114     // connection parameter range used to answer connection parameter update requests in l2cap
3115     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3116     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3117     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3118     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3119     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3120     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3121 
3122     hci_state_reset();
3123 }
3124 
3125 void hci_deinit(void){
3126 #ifdef HAVE_MALLOC
3127     if (hci_stack) {
3128         free(hci_stack);
3129     }
3130 #endif
3131     hci_stack = NULL;
3132 
3133 #ifdef ENABLE_CLASSIC
3134     disable_l2cap_timeouts = 0;
3135 #endif
3136 }
3137 
3138 /**
3139  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3140  */
3141 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3142     hci_stack->chipset = chipset_driver;
3143 
3144     // reset chipset driver - init is also called on power_up
3145     if (hci_stack->chipset && hci_stack->chipset->init){
3146         hci_stack->chipset->init(hci_stack->config);
3147     }
3148 }
3149 
3150 /**
3151  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3152  */
3153 void hci_set_control(const btstack_control_t *hardware_control){
3154     // references to used control implementation
3155     hci_stack->control = hardware_control;
3156     // init with transport config
3157     hardware_control->init(hci_stack->config);
3158 }
3159 
3160 void hci_close(void){
3161     // close remote device db
3162     if (hci_stack->link_key_db) {
3163         hci_stack->link_key_db->close();
3164     }
3165 
3166     btstack_linked_list_iterator_t lit;
3167     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3168     while (btstack_linked_list_iterator_has_next(&lit)){
3169         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3170         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3171         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3172         hci_shutdown_connection(connection);
3173     }
3174 
3175     hci_power_control(HCI_POWER_OFF);
3176 
3177 #ifdef HAVE_MALLOC
3178     free(hci_stack);
3179 #endif
3180     hci_stack = NULL;
3181 }
3182 
3183 #ifdef ENABLE_CLASSIC
3184 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3185     // validate ranage and set
3186     if (encryption_key_size < 7)  return;
3187     if (encryption_key_size > 16) return;
3188     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3189 }
3190 
3191 void gap_set_security_level(gap_security_level_t security_level){
3192     hci_stack->gap_security_level = security_level;
3193 }
3194 
3195 gap_security_level_t gap_get_security_level(void){
3196     return hci_stack->gap_security_level;
3197 }
3198 #endif
3199 
3200 #ifdef ENABLE_CLASSIC
3201 void gap_set_class_of_device(uint32_t class_of_device){
3202     hci_stack->class_of_device = class_of_device;
3203 }
3204 
3205 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3206     hci_stack->default_link_policy_settings = default_link_policy_settings;
3207 }
3208 
3209 void gap_set_allow_role_switch(bool allow_role_switch){
3210     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3211 }
3212 
3213 uint8_t hci_get_allow_role_switch(void){
3214     return  hci_stack->allow_role_switch;
3215 }
3216 
3217 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3218     hci_stack->link_supervision_timeout = link_supervision_timeout;
3219 }
3220 
3221 void hci_disable_l2cap_timeout_check(void){
3222     disable_l2cap_timeouts = 1;
3223 }
3224 #endif
3225 
3226 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3227 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3228 void hci_set_bd_addr(bd_addr_t addr){
3229     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3230     hci_stack->custom_bd_addr_set = 1;
3231 }
3232 #endif
3233 
3234 // State-Module-Driver overview
3235 // state                    module  low-level
3236 // HCI_STATE_OFF             off      close
3237 // HCI_STATE_INITIALIZING,   on       open
3238 // HCI_STATE_WORKING,        on       open
3239 // HCI_STATE_HALTING,        on       open
3240 // HCI_STATE_SLEEPING,    off/sleep   close
3241 // HCI_STATE_FALLING_ASLEEP  on       open
3242 
3243 static int hci_power_control_on(void){
3244 
3245     // power on
3246     int err = 0;
3247     if (hci_stack->control && hci_stack->control->on){
3248         err = (*hci_stack->control->on)();
3249     }
3250     if (err){
3251         log_error( "POWER_ON failed");
3252         hci_emit_hci_open_failed();
3253         return err;
3254     }
3255 
3256     // int chipset driver
3257     if (hci_stack->chipset && hci_stack->chipset->init){
3258         hci_stack->chipset->init(hci_stack->config);
3259     }
3260 
3261     // init transport
3262     if (hci_stack->hci_transport->init){
3263         hci_stack->hci_transport->init(hci_stack->config);
3264     }
3265 
3266     // open transport
3267     err = hci_stack->hci_transport->open();
3268     if (err){
3269         log_error( "HCI_INIT failed, turning Bluetooth off again");
3270         if (hci_stack->control && hci_stack->control->off){
3271             (*hci_stack->control->off)();
3272         }
3273         hci_emit_hci_open_failed();
3274         return err;
3275     }
3276     return 0;
3277 }
3278 
3279 static void hci_power_control_off(void){
3280 
3281     log_info("hci_power_control_off");
3282 
3283     // close low-level device
3284     hci_stack->hci_transport->close();
3285 
3286     log_info("hci_power_control_off - hci_transport closed");
3287 
3288     // power off
3289     if (hci_stack->control && hci_stack->control->off){
3290         (*hci_stack->control->off)();
3291     }
3292 
3293     log_info("hci_power_control_off - control closed");
3294 
3295     hci_stack->state = HCI_STATE_OFF;
3296 }
3297 
3298 static void hci_power_control_sleep(void){
3299 
3300     log_info("hci_power_control_sleep");
3301 
3302 #if 0
3303     // don't close serial port during sleep
3304 
3305     // close low-level device
3306     hci_stack->hci_transport->close(hci_stack->config);
3307 #endif
3308 
3309     // sleep mode
3310     if (hci_stack->control && hci_stack->control->sleep){
3311         (*hci_stack->control->sleep)();
3312     }
3313 
3314     hci_stack->state = HCI_STATE_SLEEPING;
3315 }
3316 
3317 static int hci_power_control_wake(void){
3318 
3319     log_info("hci_power_control_wake");
3320 
3321     // wake on
3322     if (hci_stack->control && hci_stack->control->wake){
3323         (*hci_stack->control->wake)();
3324     }
3325 
3326 #if 0
3327     // open low-level device
3328     int err = hci_stack->hci_transport->open(hci_stack->config);
3329     if (err){
3330         log_error( "HCI_INIT failed, turning Bluetooth off again");
3331         if (hci_stack->control && hci_stack->control->off){
3332             (*hci_stack->control->off)();
3333         }
3334         hci_emit_hci_open_failed();
3335         return err;
3336     }
3337 #endif
3338 
3339     return 0;
3340 }
3341 
3342 static void hci_power_transition_to_initializing(void){
3343     // set up state machine
3344     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3345     hci_stack->hci_packet_buffer_reserved = 0;
3346     hci_stack->state = HCI_STATE_INITIALIZING;
3347     hci_stack->substate = HCI_INIT_SEND_RESET;
3348 }
3349 
3350 int hci_power_control(HCI_POWER_MODE power_mode){
3351 
3352     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3353 
3354     int err = 0;
3355     switch (hci_stack->state){
3356 
3357         case HCI_STATE_OFF:
3358             switch (power_mode){
3359                 case HCI_POWER_ON:
3360                     err = hci_power_control_on();
3361                     if (err) {
3362                         log_error("hci_power_control_on() error %d", err);
3363                         return err;
3364                     }
3365                     hci_power_transition_to_initializing();
3366                     break;
3367                 case HCI_POWER_OFF:
3368                     // do nothing
3369                     break;
3370                 case HCI_POWER_SLEEP:
3371                     // do nothing (with SLEEP == OFF)
3372                     break;
3373                 default:
3374                     btstack_assert(false);
3375                     break;
3376             }
3377             break;
3378 
3379         case HCI_STATE_INITIALIZING:
3380             switch (power_mode){
3381                 case HCI_POWER_ON:
3382                     // do nothing
3383                     break;
3384                 case HCI_POWER_OFF:
3385                     // no connections yet, just turn it off
3386                     hci_power_control_off();
3387                     break;
3388                 case HCI_POWER_SLEEP:
3389                     // no connections yet, just turn it off
3390                     hci_power_control_sleep();
3391                     break;
3392                 default:
3393                     btstack_assert(false);
3394                     break;
3395             }
3396             break;
3397 
3398         case HCI_STATE_WORKING:
3399             switch (power_mode){
3400                 case HCI_POWER_ON:
3401                     // do nothing
3402                     break;
3403                 case HCI_POWER_OFF:
3404                     // see hci_run
3405                     hci_stack->state = HCI_STATE_HALTING;
3406                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3407                     break;
3408                 case HCI_POWER_SLEEP:
3409                     // see hci_run
3410                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3411                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3412                     break;
3413                 default:
3414                     btstack_assert(false);
3415                     break;
3416             }
3417             break;
3418 
3419         case HCI_STATE_HALTING:
3420             switch (power_mode){
3421                 case HCI_POWER_ON:
3422                     hci_power_transition_to_initializing();
3423                     break;
3424                 case HCI_POWER_OFF:
3425                     // do nothing
3426                     break;
3427                 case HCI_POWER_SLEEP:
3428                     // see hci_run
3429                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3430                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3431                     break;
3432                 default:
3433                     btstack_assert(false);
3434                     break;
3435             }
3436             break;
3437 
3438         case HCI_STATE_FALLING_ASLEEP:
3439             switch (power_mode){
3440                 case HCI_POWER_ON:
3441 
3442 #ifdef HAVE_PLATFORM_IPHONE_OS
3443                     // nothing to do, if H4 supports power management
3444                     if (btstack_control_iphone_power_management_enabled()){
3445                         hci_stack->state = HCI_STATE_INITIALIZING;
3446                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3447                         break;
3448                     }
3449 #endif
3450                     hci_power_transition_to_initializing();
3451                     break;
3452                 case HCI_POWER_OFF:
3453                     // see hci_run
3454                     hci_stack->state = HCI_STATE_HALTING;
3455                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3456                     break;
3457                 case HCI_POWER_SLEEP:
3458                     // do nothing
3459                     break;
3460                 default:
3461                     btstack_assert(false);
3462                     break;
3463             }
3464             break;
3465 
3466         case HCI_STATE_SLEEPING:
3467             switch (power_mode){
3468                 case HCI_POWER_ON:
3469 
3470 #ifdef HAVE_PLATFORM_IPHONE_OS
3471                     // nothing to do, if H4 supports power management
3472                     if (btstack_control_iphone_power_management_enabled()){
3473                         hci_stack->state = HCI_STATE_INITIALIZING;
3474                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3475                         hci_update_scan_enable();
3476                         break;
3477                     }
3478 #endif
3479                     err = hci_power_control_wake();
3480                     if (err) return err;
3481                     hci_power_transition_to_initializing();
3482                     break;
3483                 case HCI_POWER_OFF:
3484                     hci_stack->state = HCI_STATE_HALTING;
3485                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3486                     break;
3487                 case HCI_POWER_SLEEP:
3488                     // do nothing
3489                     break;
3490                 default:
3491                     btstack_assert(false);
3492                     break;
3493             }
3494             break;
3495 
3496         default:
3497             btstack_assert(false);
3498             break;
3499     }
3500 
3501     // create internal event
3502 	hci_emit_state();
3503 
3504 	// trigger next/first action
3505 	hci_run();
3506 
3507     return 0;
3508 }
3509 
3510 
3511 #ifdef ENABLE_CLASSIC
3512 
3513 static void hci_update_scan_enable(void){
3514     // 2 = page scan, 1 = inq scan
3515     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3516     hci_run();
3517 }
3518 
3519 void gap_discoverable_control(uint8_t enable){
3520     if (enable) enable = 1; // normalize argument
3521 
3522     if (hci_stack->discoverable == enable){
3523         hci_emit_discoverable_enabled(hci_stack->discoverable);
3524         return;
3525     }
3526 
3527     hci_stack->discoverable = enable;
3528     hci_update_scan_enable();
3529 }
3530 
3531 void gap_connectable_control(uint8_t enable){
3532     if (enable) enable = 1; // normalize argument
3533 
3534     // don't emit event
3535     if (hci_stack->connectable == enable) return;
3536 
3537     hci_stack->connectable = enable;
3538     hci_update_scan_enable();
3539 }
3540 #endif
3541 
3542 void gap_local_bd_addr(bd_addr_t address_buffer){
3543     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3544 }
3545 
3546 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3547 static void hci_host_num_completed_packets(void){
3548 
3549     // create packet manually as arrays are not supported and num_commands should not get reduced
3550     hci_reserve_packet_buffer();
3551     uint8_t * packet = hci_get_outgoing_packet_buffer();
3552 
3553     uint16_t size = 0;
3554     uint16_t num_handles = 0;
3555     packet[size++] = 0x35;
3556     packet[size++] = 0x0c;
3557     size++;  // skip param len
3558     size++;  // skip num handles
3559 
3560     // add { handle, packets } entries
3561     btstack_linked_item_t * it;
3562     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3563         hci_connection_t * connection = (hci_connection_t *) it;
3564         if (connection->num_packets_completed){
3565             little_endian_store_16(packet, size, connection->con_handle);
3566             size += 2;
3567             little_endian_store_16(packet, size, connection->num_packets_completed);
3568             size += 2;
3569             //
3570             num_handles++;
3571             connection->num_packets_completed = 0;
3572         }
3573     }
3574 
3575     packet[2] = size - 3;
3576     packet[3] = num_handles;
3577 
3578     hci_stack->host_completed_packets = 0;
3579 
3580     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3581     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3582 
3583     // release packet buffer for synchronous transport implementations
3584     if (hci_transport_synchronous()){
3585         hci_release_packet_buffer();
3586         hci_emit_transport_packet_sent();
3587     }
3588 }
3589 #endif
3590 
3591 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3592     UNUSED(ds);
3593     hci_stack->substate = HCI_HALTING_CLOSE;
3594     // allow packet handlers to defer final shutdown
3595     hci_emit_state();
3596     hci_run();
3597 }
3598 
3599 static bool hci_run_acl_fragments(void){
3600     if (hci_stack->acl_fragmentation_total_size > 0u) {
3601         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3602         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3603         if (connection) {
3604             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3605                 hci_send_acl_packet_fragments(connection);
3606                 return true;
3607             }
3608         } else {
3609             // connection gone -> discard further fragments
3610             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3611             hci_stack->acl_fragmentation_total_size = 0;
3612             hci_stack->acl_fragmentation_pos = 0;
3613         }
3614     }
3615     return false;
3616 }
3617 
3618 #ifdef ENABLE_CLASSIC
3619 static bool hci_run_general_gap_classic(void){
3620 
3621     // decline incoming connections
3622     if (hci_stack->decline_reason){
3623         uint8_t reason = hci_stack->decline_reason;
3624         hci_stack->decline_reason = 0;
3625         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3626         return true;
3627     }
3628     // send scan enable
3629     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3630         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3631         hci_stack->new_scan_enable_value = 0xff;
3632         return true;
3633     }
3634     // start/stop inquiry
3635     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3636         uint8_t duration = hci_stack->inquiry_state;
3637         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3638         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3639         return true;
3640     }
3641     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3642         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3643         hci_send_cmd(&hci_inquiry_cancel);
3644         return true;
3645     }
3646     // remote name request
3647     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3648         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3649         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3650                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3651         return true;
3652     }
3653     // pairing
3654     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3655         uint8_t state = hci_stack->gap_pairing_state;
3656         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3657         switch (state){
3658             case GAP_PAIRING_STATE_SEND_PIN:
3659                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, hci_stack->gap_pairing_input.gap_pairing_pin);
3660                 break;
3661             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3662                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3663                 break;
3664             case GAP_PAIRING_STATE_SEND_PASSKEY:
3665                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3666                 break;
3667             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3668                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3669                 break;
3670             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3671                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3672                 break;
3673             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3674                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3675                 break;
3676             default:
3677                 break;
3678         }
3679         return true;
3680     }
3681     return false;
3682 }
3683 #endif
3684 
3685 #ifdef ENABLE_BLE
3686 static bool hci_run_general_gap_le(void){
3687 
3688     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3689 
3690     if (hci_stack->state != HCI_STATE_WORKING) return false;
3691     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3692 
3693 
3694     // Phase 1: collect what to stop
3695 
3696     bool scanning_stop = false;
3697     bool connecting_stop = false;
3698     bool advertising_stop = false;
3699 
3700 #ifndef ENABLE_LE_CENTRAL
3701     UNUSED(scanning_stop);
3702     UNUSED(connecting_stop);
3703 #endif
3704 #ifndef ENABLE_LE_PERIPHERAL
3705     UNUSED(advertising_stop);
3706 #endif
3707 
3708     // check if whitelist needs modification
3709     bool whitelist_modification_pending = false;
3710     btstack_linked_list_iterator_t lit;
3711     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3712     while (btstack_linked_list_iterator_has_next(&lit)){
3713         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3714         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3715             whitelist_modification_pending = true;
3716             break;
3717         }
3718     }
3719     // check if resolving list needs modification
3720     bool resolving_list_modification_pending = false;
3721 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3722     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
3723 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
3724         resolving_list_modification_pending = true;
3725     }
3726 #endif
3727 
3728 #ifdef ENABLE_LE_CENTRAL
3729     // scanning control
3730     if (hci_stack->le_scanning_active) {
3731         // stop if:
3732         // - parameter change required
3733         // - it's disabled
3734         // - whitelist change required but used for scanning
3735         // - resolving list modified
3736         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3737         if ((hci_stack->le_scanning_param_update) ||
3738             !hci_stack->le_scanning_enabled ||
3739             scanning_uses_whitelist ||
3740             resolving_list_modification_pending){
3741 
3742             scanning_stop = true;
3743         }
3744     }
3745 #endif
3746 
3747 #ifdef ENABLE_LE_CENTRAL
3748     // connecting control
3749     bool connecting_with_whitelist;
3750     switch (hci_stack->le_connecting_state){
3751         case LE_CONNECTING_DIRECT:
3752         case LE_CONNECTING_WHITELIST:
3753             // stop connecting if:
3754             // - connecting uses white and whitelist modification pending
3755             // - if it got disabled
3756             // - resolving list modified
3757             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
3758             if ((connecting_with_whitelist && whitelist_modification_pending) ||
3759                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
3760                 resolving_list_modification_pending) {
3761 
3762                 connecting_stop = true;
3763             }
3764             break;
3765         default:
3766             break;
3767     }
3768 #endif
3769 
3770 #ifdef ENABLE_LE_PERIPHERAL
3771     // le advertisement control
3772     if (hci_stack->le_advertisements_active){
3773         // stop if:
3774         // - parameter change required
3775         // - it's disabled
3776         // - whitelist change required but used for advertisement filter policy
3777         // - resolving list modified
3778         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3779         if ((hci_stack->le_advertisements_todo != 0) ||
3780             !hci_stack->le_advertisements_enabled_for_current_roles ||
3781             (advertising_uses_whitelist & whitelist_modification_pending) ||
3782             resolving_list_modification_pending) {
3783 
3784             advertising_stop = true;
3785         }
3786     }
3787 #endif
3788 
3789 
3790     // Phase 2: stop everything that should be off during modifications
3791 
3792 #ifdef ENABLE_LE_CENTRAL
3793     if (scanning_stop){
3794         hci_stack->le_scanning_active = false;
3795         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3796         return true;
3797     }
3798 #endif
3799 
3800 #ifdef ENABLE_LE_CENTRAL
3801     if (connecting_stop){
3802         hci_send_cmd(&hci_le_create_connection_cancel);
3803         return true;
3804     }
3805 #endif
3806 
3807 #ifdef ENABLE_LE_PERIPHERAL
3808     if (advertising_stop){
3809         hci_stack->le_advertisements_active = false;
3810         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3811         return true;
3812     }
3813 #endif
3814 
3815     // Phase 3: modify
3816 
3817 #ifdef ENABLE_LE_CENTRAL
3818     if (hci_stack->le_scanning_param_update){
3819         hci_stack->le_scanning_param_update = false;
3820         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3821                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3822         return true;
3823     }
3824 #endif
3825 
3826 #ifdef ENABLE_LE_PERIPHERAL
3827     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3828         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3829         hci_send_cmd(&hci_le_set_advertising_parameters,
3830                      hci_stack->le_advertisements_interval_min,
3831                      hci_stack->le_advertisements_interval_max,
3832                      hci_stack->le_advertisements_type,
3833                      hci_stack->le_own_addr_type,
3834                      hci_stack->le_advertisements_direct_address_type,
3835                      hci_stack->le_advertisements_direct_address,
3836                      hci_stack->le_advertisements_channel_map,
3837                      hci_stack->le_advertisements_filter_policy);
3838         return true;
3839     }
3840     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3841         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3842         uint8_t adv_data_clean[31];
3843         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3844         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3845                      hci_stack->le_advertisements_data_len);
3846         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3847         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3848         return true;
3849     }
3850     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3851         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3852         uint8_t scan_data_clean[31];
3853         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3854         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3855                      hci_stack->le_scan_response_data_len);
3856         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3857         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3858         return true;
3859     }
3860 #endif
3861 
3862 
3863 #ifdef ENABLE_LE_CENTRAL
3864     // if connect with whitelist was active and is not cancelled yet, wait until next time
3865     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
3866 #endif
3867 
3868     // LE Whitelist Management
3869     if (whitelist_modification_pending){
3870         // add/remove entries
3871         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3872         while (btstack_linked_list_iterator_has_next(&lit)){
3873             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3874 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3875 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3876 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
3877 				return true;
3878 			}
3879             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3880 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
3881                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
3882                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3883                 return true;
3884             }
3885             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
3886 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3887 				btstack_memory_whitelist_entry_free(entry);
3888             }
3889         }
3890     }
3891 
3892 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3893     // LE Resolving List Management
3894     if (resolving_list_supported) {
3895 		uint16_t i;
3896 		switch (hci_stack->le_resolving_list_state) {
3897 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
3898 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
3899 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
3900 				return true;
3901 			case LE_RESOLVING_LIST_READ_SIZE:
3902 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
3903 				hci_send_cmd(&hci_le_read_resolving_list_size);
3904 				return true;
3905 			case LE_RESOLVING_LIST_SEND_CLEAR:
3906 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
3907 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
3908 							  sizeof(hci_stack->le_resolving_list_add_entries));
3909 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
3910 							  sizeof(hci_stack->le_resolving_list_remove_entries));
3911 				hci_send_cmd(&hci_le_clear_resolving_list);
3912 				return true;
3913 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
3914 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3915 					uint8_t offset = i >> 3;
3916 					uint8_t mask = 1 << (i & 7);
3917 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
3918 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
3919 					bd_addr_t peer_identity_addreses;
3920 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3921 					sm_key_t peer_irk;
3922 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3923 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3924 
3925 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
3926 					// trigger whitelist entry 'update' (work around for controller bug)
3927 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3928 					while (btstack_linked_list_iterator_has_next(&lit)) {
3929 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
3930 						if (entry->address_type != peer_identity_addr_type) continue;
3931 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
3932 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
3933 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
3934 					}
3935 #endif
3936 
3937 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
3938 								 peer_identity_addreses);
3939 					return true;
3940 				}
3941 
3942 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
3943 
3944 				/* fall through */
3945 
3946 			case LE_RESOLVING_LIST_ADD_ENTRIES:
3947 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3948 					uint8_t offset = i >> 3;
3949 					uint8_t mask = 1 << (i & 7);
3950 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
3951 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
3952 					bd_addr_t peer_identity_addreses;
3953 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3954 					sm_key_t peer_irk;
3955 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3956 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3957 					const uint8_t *local_irk = gap_get_persistent_irk();
3958 					// command uses format specifier 'P' that stores 16-byte value without flip
3959 					uint8_t local_irk_flipped[16];
3960 					uint8_t peer_irk_flipped[16];
3961 					reverse_128(local_irk, local_irk_flipped);
3962 					reverse_128(peer_irk, peer_irk_flipped);
3963 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
3964 								 peer_irk_flipped, local_irk_flipped);
3965 					return true;
3966 				}
3967 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3968 				break;
3969 
3970 			default:
3971 				break;
3972 		}
3973 	}
3974     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3975 #endif
3976 
3977     // Phase 4: restore state
3978 
3979 #ifdef ENABLE_LE_CENTRAL
3980     // re-start scanning
3981     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3982         hci_stack->le_scanning_active = true;
3983         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3984         return true;
3985     }
3986 #endif
3987 
3988 #ifdef ENABLE_LE_CENTRAL
3989     // re-start connecting
3990     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3991         bd_addr_t null_addr;
3992         memset(null_addr, 0, 6);
3993         hci_send_cmd(&hci_le_create_connection,
3994                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3995                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3996                      1,         // use whitelist
3997                      0,         // peer address type
3998                      null_addr, // peer bd addr
3999                      hci_stack->le_own_addr_type, // our addr type:
4000                      hci_stack->le_connection_interval_min,    // conn interval min
4001                      hci_stack->le_connection_interval_max,    // conn interval max
4002                      hci_stack->le_connection_latency,         // conn latency
4003                      hci_stack->le_supervision_timeout,        // conn latency
4004                      hci_stack->le_minimum_ce_length,          // min ce length
4005                      hci_stack->le_maximum_ce_length           // max ce length
4006         );
4007         return true;
4008     }
4009 #endif
4010 
4011 #ifdef ENABLE_LE_PERIPHERAL
4012     // re-start advertising
4013     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4014         // check if advertisements should be enabled given
4015         hci_stack->le_advertisements_active = true;
4016         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4017         return true;
4018     }
4019 #endif
4020 
4021     return false;
4022 }
4023 #endif
4024 
4025 static bool hci_run_general_pending_commands(void){
4026     btstack_linked_item_t * it;
4027     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4028         hci_connection_t * connection = (hci_connection_t *) it;
4029 
4030         switch(connection->state){
4031             case SEND_CREATE_CONNECTION:
4032                 switch(connection->address_type){
4033 #ifdef ENABLE_CLASSIC
4034                     case BD_ADDR_TYPE_ACL:
4035                         log_info("sending hci_create_connection");
4036                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4037                         break;
4038 #endif
4039                     default:
4040 #ifdef ENABLE_BLE
4041 #ifdef ENABLE_LE_CENTRAL
4042                         log_info("sending hci_le_create_connection");
4043                         hci_send_cmd(&hci_le_create_connection,
4044                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4045                                      hci_stack->le_connection_scan_window,      // conn scan windows
4046                                      0,         // don't use whitelist
4047                                      connection->address_type, // peer address type
4048                                      connection->address,      // peer bd addr
4049                                      hci_stack->le_own_addr_type, // our addr type:
4050                                      hci_stack->le_connection_interval_min,    // conn interval min
4051                                      hci_stack->le_connection_interval_max,    // conn interval max
4052                                      hci_stack->le_connection_latency,         // conn latency
4053                                      hci_stack->le_supervision_timeout,        // conn latency
4054                                      hci_stack->le_minimum_ce_length,          // min ce length
4055                                      hci_stack->le_maximum_ce_length          // max ce length
4056                         );
4057                         connection->state = SENT_CREATE_CONNECTION;
4058 #endif
4059 #endif
4060                         break;
4061                 }
4062                 return true;
4063 
4064 #ifdef ENABLE_CLASSIC
4065             case RECEIVED_CONNECTION_REQUEST:
4066                 connection->role  = HCI_ROLE_SLAVE;
4067                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4068                     log_info("sending hci_accept_connection_request");
4069                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4070                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4071                 }
4072                 return true;
4073 #endif
4074 
4075 #ifdef ENABLE_BLE
4076 #ifdef ENABLE_LE_CENTRAL
4077             case SEND_CANCEL_CONNECTION:
4078                 connection->state = SENT_CANCEL_CONNECTION;
4079                 hci_send_cmd(&hci_le_create_connection_cancel);
4080                 return true;
4081 #endif
4082 #endif
4083             case SEND_DISCONNECT:
4084                 connection->state = SENT_DISCONNECT;
4085                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4086                 return true;
4087 
4088             default:
4089                 break;
4090         }
4091 
4092         // no further commands if connection is about to get shut down
4093         if (connection->state == SENT_DISCONNECT) continue;
4094 
4095         if (connection->authentication_flags & READ_RSSI){
4096             connectionClearAuthenticationFlags(connection, READ_RSSI);
4097             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4098             return true;
4099         }
4100 
4101 #ifdef ENABLE_CLASSIC
4102 
4103         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4104             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4105             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4106             return true;
4107         }
4108 
4109         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
4110             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4111             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4112 
4113             link_key_t link_key;
4114             link_key_type_t link_key_type;
4115             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
4116 
4117             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4118             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4119             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
4120             if (sc_downgrade){
4121                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4122                 connection->state = SENT_DISCONNECT;
4123                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4124                 return true;
4125             }
4126 
4127             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
4128             if (have_link_key && security_level_sufficient){
4129                 connection->link_key_type = link_key_type;
4130                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
4131             } else {
4132                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4133             }
4134             return true;
4135         }
4136 
4137         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4138             log_info("denying to pin request");
4139             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4140             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4141             return true;
4142         }
4143 
4144         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4145             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4146             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
4147             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
4148                 // tweak authentication requirements
4149                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
4150                 if (connection->bonding_flags & BONDING_DEDICATED){
4151                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4152                 }
4153                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4154                     authreq |= 1;
4155                 }
4156                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
4157             } else {
4158                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4159             }
4160             return true;
4161         }
4162 
4163         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4164             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4165             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4166             return true;
4167         }
4168 
4169         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4170             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4171             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4172             return true;
4173         }
4174 
4175         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4176             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4177             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4178             return true;
4179         }
4180 
4181         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4182             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4183             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4184             return true;
4185         }
4186 
4187         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4188             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4189             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4190             return true;
4191         }
4192 
4193         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4194             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4195             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4196             connection->state = SENT_DISCONNECT;
4197             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4198             return true;
4199         }
4200 
4201         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4202             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4203             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4204             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4205             return true;
4206         }
4207 
4208         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4209             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4210             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4211             return true;
4212         }
4213         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4214             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4215             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4216             return true;
4217         }
4218 #endif
4219 
4220         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4221             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4222             if (connection->state != SENT_DISCONNECT){
4223                 connection->state = SENT_DISCONNECT;
4224                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4225                 return true;
4226             }
4227         }
4228 
4229 #ifdef ENABLE_CLASSIC
4230         uint16_t sniff_min_interval;
4231         switch (connection->sniff_min_interval){
4232             case 0:
4233                 break;
4234             case 0xffff:
4235                 connection->sniff_min_interval = 0;
4236                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4237                 return true;
4238             default:
4239                 sniff_min_interval = connection->sniff_min_interval;
4240                 connection->sniff_min_interval = 0;
4241                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4242                 return true;
4243         }
4244 
4245         if (connection->request_role != HCI_ROLE_INVALID){
4246             hci_role_t  role = connection->request_role;
4247             connection->request_role = HCI_ROLE_INVALID;
4248             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4249             return true;
4250         }
4251 #endif
4252 
4253 #ifdef ENABLE_BLE
4254         switch (connection->le_con_parameter_update_state){
4255             // response to L2CAP CON PARAMETER UPDATE REQUEST
4256             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4257                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4258                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4259                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4260                              0x0000, 0xffff);
4261                 return true;
4262             case CON_PARAMETER_UPDATE_REPLY:
4263                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4264                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4265                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4266                              0x0000, 0xffff);
4267                 return true;
4268             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4269                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4270                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4271                 return true;
4272             default:
4273                 break;
4274         }
4275         if (connection->le_phy_update_all_phys != 0xffu){
4276             uint8_t all_phys = connection->le_phy_update_all_phys;
4277             connection->le_phy_update_all_phys = 0xff;
4278             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);
4279             return true;
4280         }
4281 #endif
4282     }
4283     return false;
4284 }
4285 
4286 static void hci_run(void){
4287 
4288     bool done;
4289 
4290     // send continuation fragments first, as they block the prepared packet buffer
4291     done = hci_run_acl_fragments();
4292     if (done) return;
4293 
4294 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4295     // send host num completed packets next as they don't require num_cmd_packets > 0
4296     if (!hci_can_send_comand_packet_transport()) return;
4297     if (hci_stack->host_completed_packets){
4298         hci_host_num_completed_packets();
4299         return;
4300     }
4301 #endif
4302 
4303     if (!hci_can_send_command_packet_now()) return;
4304 
4305     // global/non-connection oriented commands
4306 
4307 
4308 #ifdef ENABLE_CLASSIC
4309     // general gap classic
4310     done = hci_run_general_gap_classic();
4311     if (done) return;
4312 #endif
4313 
4314 #ifdef ENABLE_BLE
4315     // general gap le
4316     done = hci_run_general_gap_le();
4317     if (done) return;
4318 #endif
4319 
4320     // send pending HCI commands
4321     done = hci_run_general_pending_commands();
4322     if (done) return;
4323 
4324     // stack state sub statemachines
4325     hci_connection_t * connection;
4326     switch (hci_stack->state){
4327         case HCI_STATE_INITIALIZING:
4328             hci_initializing_run();
4329             break;
4330 
4331         case HCI_STATE_HALTING:
4332 
4333             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4334             switch (hci_stack->substate){
4335                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4336                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4337 
4338 #ifdef ENABLE_BLE
4339 #ifdef ENABLE_LE_CENTRAL
4340                     // free whitelist entries
4341                     {
4342                         btstack_linked_list_iterator_t lit;
4343                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4344                         while (btstack_linked_list_iterator_has_next(&lit)){
4345                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4346                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4347                             btstack_memory_whitelist_entry_free(entry);
4348                         }
4349                     }
4350 #endif
4351 #endif
4352                     // close all open connections
4353                     connection =  (hci_connection_t *) hci_stack->connections;
4354                     if (connection){
4355                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4356                         if (!hci_can_send_command_packet_now()) return;
4357 
4358                         // check state
4359                         if (connection->state == SENT_DISCONNECT) return;
4360                         connection->state = SENT_DISCONNECT;
4361 
4362                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4363 
4364                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4365                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4366 
4367                         // ... which would be ignored anyway as we shutdown (free) the connection now
4368                         hci_shutdown_connection(connection);
4369 
4370                         // finally, send the disconnect command
4371                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4372                         return;
4373                     }
4374 
4375                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4376                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4377                         log_info("HCI_STATE_HALTING: wait 50 ms");
4378                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4379                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4380                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4381                         btstack_run_loop_add_timer(&hci_stack->timeout);
4382                         break;
4383                     }
4384 
4385                     /* fall through */
4386 
4387                 case HCI_HALTING_CLOSE:
4388                     log_info("HCI_STATE_HALTING, calling off");
4389 
4390                     // switch mode
4391                     hci_power_control_off();
4392 
4393                     log_info("HCI_STATE_HALTING, emitting state");
4394                     hci_emit_state();
4395                     log_info("HCI_STATE_HALTING, done");
4396                     break;
4397 
4398                 case HCI_HALTING_W4_TIMER:
4399                     // keep waiting
4400 
4401                     break;
4402                 default:
4403                     break;
4404             }
4405 
4406             break;
4407 
4408         case HCI_STATE_FALLING_ASLEEP:
4409             switch(hci_stack->substate) {
4410                 case HCI_FALLING_ASLEEP_DISCONNECT:
4411                     log_info("HCI_STATE_FALLING_ASLEEP");
4412                     // close all open connections
4413                     connection =  (hci_connection_t *) hci_stack->connections;
4414 
4415 #ifdef HAVE_PLATFORM_IPHONE_OS
4416                     // don't close connections, if H4 supports power management
4417                     if (btstack_control_iphone_power_management_enabled()){
4418                         connection = NULL;
4419                     }
4420 #endif
4421                     if (connection){
4422 
4423                         // send disconnect
4424                         if (!hci_can_send_command_packet_now()) return;
4425 
4426                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4427                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4428 
4429                         // send disconnected event right away - causes higher layer connections to get closed, too.
4430                         hci_shutdown_connection(connection);
4431                         return;
4432                     }
4433 
4434                     if (hci_classic_supported()){
4435                         // disable page and inquiry scan
4436                         if (!hci_can_send_command_packet_now()) return;
4437 
4438                         log_info("HCI_STATE_HALTING, disabling inq scans");
4439                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4440 
4441                         // continue in next sub state
4442                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4443                         break;
4444                     }
4445 
4446                     /* fall through */
4447 
4448                 case HCI_FALLING_ASLEEP_COMPLETE:
4449                     log_info("HCI_STATE_HALTING, calling sleep");
4450 #ifdef HAVE_PLATFORM_IPHONE_OS
4451                     // don't actually go to sleep, if H4 supports power management
4452                     if (btstack_control_iphone_power_management_enabled()){
4453                         // SLEEP MODE reached
4454                         hci_stack->state = HCI_STATE_SLEEPING;
4455                         hci_emit_state();
4456                         break;
4457                     }
4458 #endif
4459                     // switch mode
4460                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4461                     hci_emit_state();
4462                     break;
4463 
4464                 default:
4465                     break;
4466             }
4467             break;
4468 
4469         default:
4470             break;
4471     }
4472 }
4473 
4474 int hci_send_cmd_packet(uint8_t *packet, int size){
4475     // house-keeping
4476 
4477 #ifdef ENABLE_CLASSIC
4478     bd_addr_t addr;
4479     hci_connection_t * conn;
4480 #endif
4481 #ifdef ENABLE_LE_CENTRAL
4482     uint8_t initiator_filter_policy;
4483 #endif
4484 
4485     uint16_t opcode = little_endian_read_16(packet, 0);
4486     switch (opcode) {
4487         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4488             hci_stack->loopback_mode = packet[3];
4489             break;
4490 
4491 #ifdef ENABLE_CLASSIC
4492         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4493             reverse_bd_addr(&packet[3], addr);
4494             log_info("Create_connection to %s", bd_addr_to_str(addr));
4495 
4496             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4497             if (!conn) {
4498                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4499                 if (!conn) {
4500                     // notify client that alloc failed
4501                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4502                     return -1; // packet not sent to controller
4503                 }
4504                 conn->state = SEND_CREATE_CONNECTION;
4505                 conn->role  = HCI_ROLE_MASTER;
4506             }
4507             log_info("conn state %u", conn->state);
4508             switch (conn->state) {
4509                 // if connection active exists
4510                 case OPEN:
4511                     // and OPEN, emit connection complete command
4512                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4513                     return -1; // packet not sent to controller
4514                 case RECEIVED_DISCONNECTION_COMPLETE:
4515                     // create connection triggered in disconnect complete event, let's do it now
4516                     break;
4517                 case SEND_CREATE_CONNECTION:
4518                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4519                     break;
4520                 default:
4521                     // otherwise, just ignore as it is already in the open process
4522                     return -1; // packet not sent to controller
4523             }
4524             conn->state = SENT_CREATE_CONNECTION;
4525 
4526             // track outgoing connection
4527             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4528             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4529             break;
4530         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4531             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4532             break;
4533         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4534             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4535             break;
4536         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4537             if (hci_stack->link_key_db) {
4538                 reverse_bd_addr(&packet[3], addr);
4539                 hci_stack->link_key_db->delete_link_key(addr);
4540             }
4541             break;
4542         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4543         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4544             reverse_bd_addr(&packet[3], addr);
4545             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4546             if (conn) {
4547                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4548             }
4549             break;
4550         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4551         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4552         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4553         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4554             reverse_bd_addr(&packet[3], addr);
4555             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4556             if (conn) {
4557                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4558             }
4559             break;
4560 
4561 #ifdef ENABLE_SCO_OVER_HCI
4562         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4563             // setup_synchronous_connection? Voice setting at offset 22
4564             // TODO: compare to current setting if sco connection already active
4565             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4566             break;
4567         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4568             // accept_synchronus_connection? Voice setting at offset 18
4569             // TODO: compare to current setting if sco connection already active
4570             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4571             break;
4572 #endif
4573 #endif
4574 
4575 #ifdef ENABLE_BLE
4576         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4577             hci_stack->le_random_address_set = 1;
4578             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4579             break;
4580 #ifdef ENABLE_LE_PERIPHERAL
4581         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4582             hci_stack->le_advertisements_active = packet[3] != 0;
4583             break;
4584 #endif
4585 #ifdef ENABLE_LE_CENTRAL
4586         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4587             // white list used?
4588             initiator_filter_policy = packet[7];
4589             switch (initiator_filter_policy) {
4590                 case 0:
4591                     // whitelist not used
4592                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4593                     break;
4594                 case 1:
4595                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4596                     break;
4597                 default:
4598                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4599                     break;
4600             }
4601             // track outgoing connection
4602             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4603             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4604             break;
4605         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4606             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4607             break;
4608 #endif
4609 #endif
4610         default:
4611             break;
4612     }
4613 
4614     hci_stack->num_cmd_packets--;
4615 
4616     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4617     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4618 }
4619 
4620 // disconnect because of security block
4621 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4622     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4623     if (!connection) return;
4624     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4625 }
4626 
4627 
4628 // Configure Secure Simple Pairing
4629 
4630 #ifdef ENABLE_CLASSIC
4631 
4632 // enable will enable SSP during init
4633 void gap_ssp_set_enable(int enable){
4634     hci_stack->ssp_enable = enable;
4635 }
4636 
4637 static int hci_local_ssp_activated(void){
4638     return gap_ssp_supported() && hci_stack->ssp_enable;
4639 }
4640 
4641 // if set, BTstack will respond to io capability request using authentication requirement
4642 void gap_ssp_set_io_capability(int io_capability){
4643     hci_stack->ssp_io_capability = io_capability;
4644 }
4645 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4646     hci_stack->ssp_authentication_requirement = authentication_requirement;
4647 }
4648 
4649 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4650 void gap_ssp_set_auto_accept(int auto_accept){
4651     hci_stack->ssp_auto_accept = auto_accept;
4652 }
4653 
4654 void gap_secure_connections_enable(bool enable){
4655     hci_stack->secure_connections_enable = enable;
4656 }
4657 
4658 #endif
4659 
4660 // va_list part of hci_send_cmd
4661 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4662     if (!hci_can_send_command_packet_now()){
4663         log_error("hci_send_cmd called but cannot send packet now");
4664         return 0;
4665     }
4666 
4667     // for HCI INITIALIZATION
4668     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4669     hci_stack->last_cmd_opcode = cmd->opcode;
4670 
4671     hci_reserve_packet_buffer();
4672     uint8_t * packet = hci_stack->hci_packet_buffer;
4673     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4674     int err = hci_send_cmd_packet(packet, size);
4675 
4676     // release packet buffer on error or for synchronous transport implementations
4677     if ((err < 0) || hci_transport_synchronous()){
4678         hci_release_packet_buffer();
4679         hci_emit_transport_packet_sent();
4680     }
4681 
4682     return err;
4683 }
4684 
4685 /**
4686  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4687  */
4688 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4689     va_list argptr;
4690     va_start(argptr, cmd);
4691     int res = hci_send_cmd_va_arg(cmd, argptr);
4692     va_end(argptr);
4693     return res;
4694 }
4695 
4696 // Create various non-HCI events.
4697 // TODO: generalize, use table similar to hci_create_command
4698 
4699 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4700     // dump packet
4701     if (dump) {
4702         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4703     }
4704 
4705     // dispatch to all event handlers
4706     btstack_linked_list_iterator_t it;
4707     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4708     while (btstack_linked_list_iterator_has_next(&it)){
4709         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4710         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4711     }
4712 }
4713 
4714 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4715     if (!hci_stack->acl_packet_handler) return;
4716     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4717 }
4718 
4719 #ifdef ENABLE_CLASSIC
4720 static void hci_notify_if_sco_can_send_now(void){
4721     // notify SCO sender if waiting
4722     if (!hci_stack->sco_waiting_for_can_send_now) return;
4723     if (hci_can_send_sco_packet_now()){
4724         hci_stack->sco_waiting_for_can_send_now = 0;
4725         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4726         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4727         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4728     }
4729 }
4730 
4731 // parsing end emitting has been merged to reduce code size
4732 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4733     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4734 
4735     uint8_t * eir_data;
4736     ad_context_t context;
4737     const uint8_t * name;
4738     uint8_t         name_len;
4739 
4740     if (size < 3) return;
4741 
4742     int event_type = hci_event_packet_get_type(packet);
4743     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4744     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4745 
4746     switch (event_type){
4747         case HCI_EVENT_INQUIRY_RESULT:
4748         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4749             if (size != (3 + (num_responses * 14))) return;
4750             break;
4751         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4752             if (size != 257) return;
4753             if (num_responses != 1) return;
4754             break;
4755         default:
4756             return;
4757     }
4758 
4759     // event[1] is set at the end
4760     int i;
4761     for (i=0; i<num_responses;i++){
4762         memset(event, 0, sizeof(event));
4763         event[0] = GAP_EVENT_INQUIRY_RESULT;
4764         uint8_t event_size = 18;    // if name is not set by EIR
4765 
4766         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4767         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4768         (void)memcpy(&event[9],
4769                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4770                      3); // class of device
4771         (void)memcpy(&event[12],
4772                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4773                      2); // clock offset
4774 
4775         switch (event_type){
4776             case HCI_EVENT_INQUIRY_RESULT:
4777                 // 14,15,16,17 = 0, size 18
4778                 break;
4779             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4780                 event[14] = 1;
4781                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4782                 // 16,17 = 0, size 18
4783                 break;
4784             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4785                 event[14] = 1;
4786                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4787                 // EIR packets only contain a single inquiry response
4788                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4789                 name = NULL;
4790                 // Iterate over EIR data
4791                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4792                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4793                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4794                     const uint8_t * data = ad_iterator_get_data(&context);
4795                     // Prefer Complete Local Name over Shortend Local Name
4796                     switch (data_type){
4797                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4798                             if (name) continue;
4799                             /* fall through */
4800                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4801                             name = data;
4802                             name_len = data_size;
4803                             break;
4804                         default:
4805                             break;
4806                     }
4807                 }
4808                 if (name){
4809                     event[16] = 1;
4810                     // truncate name if needed
4811                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4812                     event[17] = len;
4813                     (void)memcpy(&event[18], name, len);
4814                     event_size += len;
4815                 }
4816                 break;
4817             default:
4818                 return;
4819         }
4820         event[1] = event_size - 2;
4821         hci_emit_event(event, event_size, 1);
4822     }
4823 }
4824 #endif
4825 
4826 void hci_emit_state(void){
4827     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4828     uint8_t event[3];
4829     event[0] = BTSTACK_EVENT_STATE;
4830     event[1] = sizeof(event) - 2u;
4831     event[2] = hci_stack->state;
4832     hci_emit_event(event, sizeof(event), 1);
4833 }
4834 
4835 #ifdef ENABLE_CLASSIC
4836 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4837     uint8_t event[13];
4838     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4839     event[1] = sizeof(event) - 2;
4840     event[2] = status;
4841     little_endian_store_16(event, 3, con_handle);
4842     reverse_bd_addr(address, &event[5]);
4843     event[11] = 1; // ACL connection
4844     event[12] = 0; // encryption disabled
4845     hci_emit_event(event, sizeof(event), 1);
4846 }
4847 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4848     if (disable_l2cap_timeouts) return;
4849     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4850     uint8_t event[4];
4851     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4852     event[1] = sizeof(event) - 2;
4853     little_endian_store_16(event, 2, conn->con_handle);
4854     hci_emit_event(event, sizeof(event), 1);
4855 }
4856 #endif
4857 
4858 #ifdef ENABLE_BLE
4859 #ifdef ENABLE_LE_CENTRAL
4860 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){
4861     uint8_t event[21];
4862     event[0] = HCI_EVENT_LE_META;
4863     event[1] = sizeof(event) - 2u;
4864     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4865     event[3] = status;
4866     little_endian_store_16(event, 4, con_handle);
4867     event[6] = 0; // TODO: role
4868     event[7] = address_type;
4869     reverse_bd_addr(address, &event[8]);
4870     little_endian_store_16(event, 14, 0); // interval
4871     little_endian_store_16(event, 16, 0); // latency
4872     little_endian_store_16(event, 18, 0); // supervision timeout
4873     event[20] = 0; // master clock accuracy
4874     hci_emit_event(event, sizeof(event), 1);
4875 }
4876 #endif
4877 #endif
4878 
4879 static void hci_emit_transport_packet_sent(void){
4880     // notify upper stack that it might be possible to send again
4881     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4882     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4883 }
4884 
4885 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4886     uint8_t event[6];
4887     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4888     event[1] = sizeof(event) - 2u;
4889     event[2] = 0; // status = OK
4890     little_endian_store_16(event, 3, con_handle);
4891     event[5] = reason;
4892     hci_emit_event(event, sizeof(event), 1);
4893 }
4894 
4895 static void hci_emit_nr_connections_changed(void){
4896     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4897     uint8_t event[3];
4898     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4899     event[1] = sizeof(event) - 2u;
4900     event[2] = nr_hci_connections();
4901     hci_emit_event(event, sizeof(event), 1);
4902 }
4903 
4904 static void hci_emit_hci_open_failed(void){
4905     log_info("BTSTACK_EVENT_POWERON_FAILED");
4906     uint8_t event[2];
4907     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4908     event[1] = sizeof(event) - 2u;
4909     hci_emit_event(event, sizeof(event), 1);
4910 }
4911 
4912 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4913     log_info("hci_emit_dedicated_bonding_result %u ", status);
4914     uint8_t event[9];
4915     int pos = 0;
4916     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4917     event[pos++] = sizeof(event) - 2u;
4918     event[pos++] = status;
4919     reverse_bd_addr(address, &event[pos]);
4920     hci_emit_event(event, sizeof(event), 1);
4921 }
4922 
4923 
4924 #ifdef ENABLE_CLASSIC
4925 
4926 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4927     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4928     uint8_t event[5];
4929     int pos = 0;
4930     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4931     event[pos++] = sizeof(event) - 2;
4932     little_endian_store_16(event, 2, con_handle);
4933     pos += 2;
4934     event[pos++] = level;
4935     hci_emit_event(event, sizeof(event), 1);
4936 }
4937 
4938 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4939     if (!connection) return LEVEL_0;
4940     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4941     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4942     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4943     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4944     // LEVEL 4 always requires 128 bit encrytion key size
4945     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4946         security_level = LEVEL_3;
4947     }
4948     return security_level;
4949 }
4950 
4951 static void hci_emit_discoverable_enabled(uint8_t enabled){
4952     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4953     uint8_t event[3];
4954     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4955     event[1] = sizeof(event) - 2;
4956     event[2] = enabled;
4957     hci_emit_event(event, sizeof(event), 1);
4958 }
4959 
4960 // query if remote side supports eSCO
4961 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4962     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4963     if (!connection) return 0;
4964     return (connection->remote_supported_features[0] & 1) != 0;
4965 }
4966 
4967 static bool hci_ssp_supported(hci_connection_t * connection){
4968     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4969     return (connection->bonding_flags & mask) == mask;
4970 }
4971 
4972 // query if remote side supports SSP
4973 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4974     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4975     if (!connection) return 0;
4976     return hci_ssp_supported(connection) ? 1 : 0;
4977 }
4978 
4979 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4980     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4981 }
4982 
4983 // GAP API
4984 /**
4985  * @bbrief enable/disable bonding. default is enabled
4986  * @praram enabled
4987  */
4988 void gap_set_bondable_mode(int enable){
4989     hci_stack->bondable = enable ? 1 : 0;
4990 }
4991 /**
4992  * @brief Get bondable mode.
4993  * @return 1 if bondable
4994  */
4995 int gap_get_bondable_mode(void){
4996     return hci_stack->bondable;
4997 }
4998 
4999 /**
5000  * @brief map link keys to security levels
5001  */
5002 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5003     switch (link_key_type){
5004         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5005             return LEVEL_4;
5006         case COMBINATION_KEY:
5007         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5008             return LEVEL_3;
5009         default:
5010             return LEVEL_2;
5011     }
5012 }
5013 
5014 /**
5015  * @brief map link keys to secure connection yes/no
5016  */
5017 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5018     switch (link_key_type){
5019         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5020         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5021             return 1;
5022         default:
5023             return 0;
5024     }
5025 }
5026 
5027 /**
5028  * @brief map link keys to authenticated
5029  */
5030 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5031     switch (link_key_type){
5032         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5033         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5034             return 1;
5035         default:
5036             return 0;
5037     }
5038 }
5039 
5040 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5041     log_info("gap_mitm_protection_required_for_security_level %u", level);
5042     return level > LEVEL_2;
5043 }
5044 
5045 /**
5046  * @brief get current security level
5047  */
5048 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5049     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5050     if (!connection) return LEVEL_0;
5051     return gap_security_level_for_connection(connection);
5052 }
5053 
5054 /**
5055  * @brief request connection to device to
5056  * @result GAP_AUTHENTICATION_RESULT
5057  */
5058 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5059     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5060     if (!connection){
5061         hci_emit_security_level(con_handle, LEVEL_0);
5062         return;
5063     }
5064 
5065     btstack_assert(hci_is_le_connection(connection) == false);
5066 
5067     gap_security_level_t current_level = gap_security_level(con_handle);
5068     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5069         requested_level, connection->requested_security_level, current_level);
5070 
5071     // assumption: earlier requested security higher than current level => security request is active
5072     if (current_level < connection->requested_security_level){
5073         if (connection->requested_security_level < requested_level){
5074             // increase requested level as new level is higher
5075 
5076             // TODO: handle re-authentication when done
5077 
5078             connection->requested_security_level = requested_level;
5079         }
5080         return;
5081     }
5082 
5083     // no request active, notify if security sufficient
5084     if (requested_level <= current_level){
5085         hci_emit_security_level(con_handle, current_level);
5086         return;
5087     }
5088 
5089     // store request
5090     connection->requested_security_level = requested_level;
5091 
5092     // start to authenticate connection if authentication not already active
5093     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
5094     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5095     hci_run();
5096 }
5097 
5098 /**
5099  * @brief start dedicated bonding with device. disconnect after bonding
5100  * @param device
5101  * @param request MITM protection
5102  * @result GAP_DEDICATED_BONDING_COMPLETE
5103  */
5104 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5105 
5106     // create connection state machine
5107     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5108 
5109     if (!connection){
5110         return BTSTACK_MEMORY_ALLOC_FAILED;
5111     }
5112 
5113     // delete linkn key
5114     gap_drop_link_key_for_bd_addr(device);
5115 
5116     // configure LEVEL_2/3, dedicated bonding
5117     connection->state = SEND_CREATE_CONNECTION;
5118     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5119     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5120     connection->bonding_flags = BONDING_DEDICATED;
5121 
5122     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5123 
5124     // handle: connnection failure (connection complete != ok)
5125     // handle: authentication failure
5126     // handle: disconnect on done
5127 
5128     hci_run();
5129 
5130     return 0;
5131 }
5132 #endif
5133 
5134 void gap_set_local_name(const char * local_name){
5135     hci_stack->local_name = local_name;
5136 }
5137 
5138 
5139 #ifdef ENABLE_BLE
5140 
5141 #ifdef ENABLE_LE_CENTRAL
5142 void gap_start_scan(void){
5143     hci_stack->le_scanning_enabled = true;
5144     hci_run();
5145 }
5146 
5147 void gap_stop_scan(void){
5148     hci_stack->le_scanning_enabled = false;
5149     hci_run();
5150 }
5151 
5152 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5153     hci_stack->le_scan_type          = scan_type;
5154     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5155     hci_stack->le_scan_interval      = scan_interval;
5156     hci_stack->le_scan_window        = scan_window;
5157     hci_stack->le_scanning_param_update = true;
5158     hci_run();
5159 }
5160 
5161 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5162     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5163 }
5164 
5165 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5166     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5167     if (!conn){
5168         // disallow if le connection is already outgoing
5169         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5170             log_error("le connection already active");
5171             return ERROR_CODE_COMMAND_DISALLOWED;
5172         }
5173 
5174         log_info("gap_connect: no connection exists yet, creating context");
5175         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5176         if (!conn){
5177             // notify client that alloc failed
5178             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5179             log_info("gap_connect: failed to alloc hci_connection_t");
5180             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5181         }
5182 
5183         // set le connecting state
5184         if (hci_is_le_connection_type(addr_type)){
5185             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5186         }
5187 
5188         conn->state = SEND_CREATE_CONNECTION;
5189         log_info("gap_connect: send create connection next");
5190         hci_run();
5191         return ERROR_CODE_SUCCESS;
5192     }
5193 
5194     if (!hci_is_le_connection(conn) ||
5195         (conn->state == SEND_CREATE_CONNECTION) ||
5196         (conn->state == SENT_CREATE_CONNECTION)) {
5197         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5198         log_error("gap_connect: classic connection or connect is already being created");
5199         return GATT_CLIENT_IN_WRONG_STATE;
5200     }
5201 
5202     // check if connection was just disconnected
5203     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5204         log_info("gap_connect: send create connection (again)");
5205         conn->state = SEND_CREATE_CONNECTION;
5206         hci_run();
5207         return ERROR_CODE_SUCCESS;
5208     }
5209 
5210     log_info("gap_connect: context exists with state %u", conn->state);
5211     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5212     hci_run();
5213     return ERROR_CODE_SUCCESS;
5214 }
5215 
5216 // @assumption: only a single outgoing LE Connection exists
5217 static hci_connection_t * gap_get_outgoing_connection(void){
5218     btstack_linked_item_t *it;
5219     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5220         hci_connection_t * conn = (hci_connection_t *) it;
5221         if (!hci_is_le_connection(conn)) continue;
5222         switch (conn->state){
5223             case SEND_CREATE_CONNECTION:
5224             case SENT_CREATE_CONNECTION:
5225             case SENT_CANCEL_CONNECTION:
5226                 return conn;
5227             default:
5228                 break;
5229         };
5230     }
5231     return NULL;
5232 }
5233 
5234 uint8_t gap_connect_cancel(void){
5235     hci_connection_t * conn = gap_get_outgoing_connection();
5236     if (!conn) return 0;
5237     switch (conn->state){
5238         case SEND_CREATE_CONNECTION:
5239             // skip sending create connection and emit event instead
5240             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5241             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5242             btstack_memory_hci_connection_free( conn );
5243             break;
5244         case SENT_CREATE_CONNECTION:
5245             // request to send cancel connection
5246             conn->state = SEND_CANCEL_CONNECTION;
5247             hci_run();
5248             break;
5249         default:
5250             break;
5251     }
5252     return 0;
5253 }
5254 #endif
5255 
5256 #ifdef ENABLE_LE_CENTRAL
5257 /**
5258  * @brief Set connection parameters for outgoing connections
5259  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5260  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5261  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5262  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5263  * @param conn_latency, default: 4
5264  * @param supervision_timeout (unit: 10ms), default: 720 ms
5265  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5266  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5267  */
5268 
5269 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5270     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5271     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5272     hci_stack->le_connection_scan_interval = conn_scan_interval;
5273     hci_stack->le_connection_scan_window = conn_scan_window;
5274     hci_stack->le_connection_interval_min = conn_interval_min;
5275     hci_stack->le_connection_interval_max = conn_interval_max;
5276     hci_stack->le_connection_latency = conn_latency;
5277     hci_stack->le_supervision_timeout = supervision_timeout;
5278     hci_stack->le_minimum_ce_length = min_ce_length;
5279     hci_stack->le_maximum_ce_length = max_ce_length;
5280 }
5281 #endif
5282 
5283 /**
5284  * @brief Updates the connection parameters for a given LE connection
5285  * @param handle
5286  * @param conn_interval_min (unit: 1.25ms)
5287  * @param conn_interval_max (unit: 1.25ms)
5288  * @param conn_latency
5289  * @param supervision_timeout (unit: 10ms)
5290  * @returns 0 if ok
5291  */
5292 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5293     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5294     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5295     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5296     connection->le_conn_interval_min = conn_interval_min;
5297     connection->le_conn_interval_max = conn_interval_max;
5298     connection->le_conn_latency = conn_latency;
5299     connection->le_supervision_timeout = supervision_timeout;
5300     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5301     hci_run();
5302     return 0;
5303 }
5304 
5305 /**
5306  * @brief Request an update of the connection parameter for a given LE connection
5307  * @param handle
5308  * @param conn_interval_min (unit: 1.25ms)
5309  * @param conn_interval_max (unit: 1.25ms)
5310  * @param conn_latency
5311  * @param supervision_timeout (unit: 10ms)
5312  * @returns 0 if ok
5313  */
5314 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5315     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5316     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5317     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5318     connection->le_conn_interval_min = conn_interval_min;
5319     connection->le_conn_interval_max = conn_interval_max;
5320     connection->le_conn_latency = conn_latency;
5321     connection->le_supervision_timeout = supervision_timeout;
5322     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5323     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5324     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5325     return 0;
5326 }
5327 
5328 #ifdef ENABLE_LE_PERIPHERAL
5329 
5330 /**
5331  * @brief Set Advertisement Data
5332  * @param advertising_data_length
5333  * @param advertising_data (max 31 octets)
5334  * @note data is not copied, pointer has to stay valid
5335  */
5336 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5337     hci_stack->le_advertisements_data_len = advertising_data_length;
5338     hci_stack->le_advertisements_data = advertising_data;
5339     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5340     hci_run();
5341 }
5342 
5343 /**
5344  * @brief Set Scan Response Data
5345  * @param advertising_data_length
5346  * @param advertising_data (max 31 octets)
5347  * @note data is not copied, pointer has to stay valid
5348  */
5349 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5350     hci_stack->le_scan_response_data_len = scan_response_data_length;
5351     hci_stack->le_scan_response_data = scan_response_data;
5352     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5353     hci_run();
5354 }
5355 
5356 /**
5357  * @brief Set Advertisement Parameters
5358  * @param adv_int_min
5359  * @param adv_int_max
5360  * @param adv_type
5361  * @param direct_address_type
5362  * @param direct_address
5363  * @param channel_map
5364  * @param filter_policy
5365  *
5366  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5367  */
5368  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5369     uint8_t direct_address_typ, bd_addr_t direct_address,
5370     uint8_t channel_map, uint8_t filter_policy) {
5371 
5372     hci_stack->le_advertisements_interval_min = adv_int_min;
5373     hci_stack->le_advertisements_interval_max = adv_int_max;
5374     hci_stack->le_advertisements_type = adv_type;
5375     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5376     hci_stack->le_advertisements_channel_map = channel_map;
5377     hci_stack->le_advertisements_filter_policy = filter_policy;
5378     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5379                  6);
5380 
5381     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5382     hci_run();
5383  }
5384 
5385 /**
5386  * @brief Enable/Disable Advertisements
5387  * @param enabled
5388  */
5389 void gap_advertisements_enable(int enabled){
5390     hci_stack->le_advertisements_enabled = enabled != 0;
5391     hci_update_advertisements_enabled_for_current_roles();
5392     hci_run();
5393 }
5394 
5395 #endif
5396 
5397 void hci_le_set_own_address_type(uint8_t own_address_type){
5398     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5399     if (own_address_type == hci_stack->le_own_addr_type) return;
5400     hci_stack->le_own_addr_type = own_address_type;
5401 
5402 #ifdef ENABLE_LE_PERIPHERAL
5403     // update advertisement parameters, too
5404     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5405     hci_run();
5406 #endif
5407 #ifdef ENABLE_LE_CENTRAL
5408     // note: we don't update scan parameters or modify ongoing connection attempts
5409 #endif
5410 }
5411 
5412 #endif
5413 
5414 uint8_t gap_disconnect(hci_con_handle_t handle){
5415     hci_connection_t * conn = hci_connection_for_handle(handle);
5416     if (!conn){
5417         hci_emit_disconnection_complete(handle, 0);
5418         return 0;
5419     }
5420     // ignore if already disconnected
5421     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5422         return 0;
5423     }
5424     conn->state = SEND_DISCONNECT;
5425     hci_run();
5426     return 0;
5427 }
5428 
5429 int gap_read_rssi(hci_con_handle_t con_handle){
5430     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5431     if (hci_connection == NULL) return 0;
5432     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5433     hci_run();
5434     return 1;
5435 }
5436 
5437 /**
5438  * @brief Get connection type
5439  * @param con_handle
5440  * @result connection_type
5441  */
5442 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5443     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5444     if (!conn) return GAP_CONNECTION_INVALID;
5445     switch (conn->address_type){
5446         case BD_ADDR_TYPE_LE_PUBLIC:
5447         case BD_ADDR_TYPE_LE_RANDOM:
5448             return GAP_CONNECTION_LE;
5449         case BD_ADDR_TYPE_SCO:
5450             return GAP_CONNECTION_SCO;
5451         case BD_ADDR_TYPE_ACL:
5452             return GAP_CONNECTION_ACL;
5453         default:
5454             return GAP_CONNECTION_INVALID;
5455     }
5456 }
5457 
5458 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5459     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5460     if (!conn) return HCI_ROLE_INVALID;
5461     return (hci_role_t) conn->role;
5462 }
5463 
5464 
5465 #ifdef ENABLE_CLASSIC
5466 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5467     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5468     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5469     conn->request_role = role;
5470     hci_run();
5471     return ERROR_CODE_SUCCESS;
5472 }
5473 #endif
5474 
5475 #ifdef ENABLE_BLE
5476 
5477 uint8_t gap_le_set_phy(hci_con_handle_t connection_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
5478     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5479     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5480 
5481     conn->le_phy_update_all_phys    = all_phys;
5482     conn->le_phy_update_tx_phys     = tx_phys;
5483     conn->le_phy_update_rx_phys     = rx_phys;
5484     conn->le_phy_update_phy_options = phy_options;
5485 
5486     hci_run();
5487 
5488     return 0;
5489 }
5490 
5491 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5492     // check if already in list
5493     btstack_linked_list_iterator_t it;
5494     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5495     while (btstack_linked_list_iterator_has_next(&it)) {
5496         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5497         if (entry->address_type != address_type) {
5498             continue;
5499         }
5500         if (memcmp(entry->address, address, 6) != 0) {
5501             continue;
5502         }
5503 		// disallow if already scheduled to add
5504 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
5505 			return ERROR_CODE_COMMAND_DISALLOWED;
5506 		}
5507 		// still on controller, but scheduled to remove -> re-add
5508 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
5509 		return ERROR_CODE_SUCCESS;
5510     }
5511     // alloc and add to list
5512     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5513     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5514     entry->address_type = address_type;
5515     (void)memcpy(entry->address, address, 6);
5516     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5517     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5518     return ERROR_CODE_SUCCESS;
5519 }
5520 
5521 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5522     btstack_linked_list_iterator_t it;
5523     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5524     while (btstack_linked_list_iterator_has_next(&it)){
5525         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5526         if (entry->address_type != address_type) {
5527             continue;
5528         }
5529         if (memcmp(entry->address, address, 6) != 0) {
5530             continue;
5531         }
5532         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5533             // remove from controller if already present
5534             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5535         }  else {
5536             // directly remove entry from whitelist
5537             btstack_linked_list_iterator_remove(&it);
5538             btstack_memory_whitelist_entry_free(entry);
5539         }
5540         return ERROR_CODE_SUCCESS;
5541     }
5542     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5543 }
5544 
5545 static void hci_whitelist_clear(void){
5546     btstack_linked_list_iterator_t it;
5547     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5548     while (btstack_linked_list_iterator_has_next(&it)){
5549         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5550         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5551             // remove from controller if already present
5552             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5553             continue;
5554         }
5555         // directly remove entry from whitelist
5556         btstack_linked_list_iterator_remove(&it);
5557         btstack_memory_whitelist_entry_free(entry);
5558     }
5559 }
5560 
5561 /**
5562  * @brief Clear Whitelist
5563  * @returns 0 if ok
5564  */
5565 uint8_t gap_whitelist_clear(void){
5566     hci_whitelist_clear();
5567     hci_run();
5568     return ERROR_CODE_SUCCESS;
5569 }
5570 
5571 /**
5572  * @brief Add Device to Whitelist
5573  * @param address_typ
5574  * @param address
5575  * @returns 0 if ok
5576  */
5577 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5578     uint8_t status = hci_whitelist_add(address_type, address);
5579     if (status){
5580         return status;
5581     }
5582     hci_run();
5583     return ERROR_CODE_SUCCESS;
5584 }
5585 
5586 /**
5587  * @brief Remove Device from Whitelist
5588  * @param address_typ
5589  * @param address
5590  * @returns 0 if ok
5591  */
5592 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5593     uint8_t status = hci_whitelist_remove(address_type, address);
5594     if (status){
5595         return status;
5596     }
5597     hci_run();
5598     return ERROR_CODE_SUCCESS;
5599 }
5600 
5601 #ifdef ENABLE_LE_CENTRAL
5602 /**
5603  *  @brief Connect with Whitelist
5604  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5605  *  @returns - if ok
5606  */
5607 uint8_t gap_connect_with_whitelist(void){
5608     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5609         return ERROR_CODE_COMMAND_DISALLOWED;
5610     }
5611     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5612     hci_run();
5613     return ERROR_CODE_SUCCESS;
5614 }
5615 
5616 /**
5617  * @brief Auto Connection Establishment - Start Connecting to device
5618  * @param address_typ
5619  * @param address
5620  * @returns 0 if ok
5621  */
5622 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
5623     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5624         return ERROR_CODE_COMMAND_DISALLOWED;
5625     }
5626 
5627     uint8_t status = hci_whitelist_add(address_type, address);
5628     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5629         return status;
5630     }
5631 
5632     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5633 
5634     hci_run();
5635     return ERROR_CODE_SUCCESS;
5636 }
5637 
5638 /**
5639  * @brief Auto Connection Establishment - Stop Connecting to device
5640  * @param address_typ
5641  * @param address
5642  * @returns 0 if ok
5643  */
5644 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
5645     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5646         return ERROR_CODE_COMMAND_DISALLOWED;
5647     }
5648 
5649     hci_whitelist_remove(address_type, address);
5650     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5651         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5652     }
5653     hci_run();
5654     return 0;
5655 }
5656 
5657 /**
5658  * @brief Auto Connection Establishment - Stop everything
5659  * @note  Convenience function to stop all active auto connection attempts
5660  */
5661 uint8_t gap_auto_connection_stop_all(void){
5662     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5663         return ERROR_CODE_COMMAND_DISALLOWED;
5664     }
5665     hci_whitelist_clear();
5666     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5667     hci_run();
5668     return ERROR_CODE_SUCCESS;
5669 }
5670 
5671 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5672     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5673     if (!conn) return 0;
5674     return conn->le_connection_interval;
5675 }
5676 #endif
5677 #endif
5678 
5679 #ifdef ENABLE_CLASSIC
5680 /**
5681  * @brief Set Extended Inquiry Response data
5682  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5683  * @note has to be done before stack starts up
5684  */
5685 void gap_set_extended_inquiry_response(const uint8_t * data){
5686     hci_stack->eir_data = data;
5687 }
5688 
5689 /**
5690  * @brief Start GAP Classic Inquiry
5691  * @param duration in 1.28s units
5692  * @return 0 if ok
5693  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5694  */
5695 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5696     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5697     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5698     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5699         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5700     }
5701     hci_stack->inquiry_state = duration_in_1280ms_units;
5702     hci_run();
5703     return 0;
5704 }
5705 
5706 /**
5707  * @brief Stop GAP Classic Inquiry
5708  * @returns 0 if ok
5709  */
5710 int gap_inquiry_stop(void){
5711     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5712         // emit inquiry complete event, before it even started
5713         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5714         hci_emit_event(event, sizeof(event), 1);
5715         return 0;
5716     }
5717     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5718     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5719     hci_run();
5720     return 0;
5721 }
5722 
5723 
5724 /**
5725  * @brief Remote Name Request
5726  * @param addr
5727  * @param page_scan_repetition_mode
5728  * @param clock_offset only used when bit 15 is set
5729  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5730  */
5731 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5732     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5733     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5734     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5735     hci_stack->remote_name_clock_offset = clock_offset;
5736     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5737     hci_run();
5738     return 0;
5739 }
5740 
5741 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
5742     hci_stack->gap_pairing_state = state;
5743     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5744     hci_run();
5745     return 0;
5746 }
5747 
5748 /**
5749  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5750  * @param addr
5751  * @param pin_data
5752  * @param pin_len
5753  * @return 0 if ok
5754  */
5755 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5756     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5757     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5758     hci_stack->gap_pairing_pin_len = pin_len;
5759     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5760 }
5761 
5762 /**
5763  * @brief Legacy Pairing Pin Code Response
5764  * @param addr
5765  * @param pin
5766  * @return 0 if ok
5767  */
5768 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
5769     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5770 }
5771 
5772 /**
5773  * @brief Abort Legacy Pairing
5774  * @param addr
5775  * @param pin
5776  * @return 0 if ok
5777  */
5778 int gap_pin_code_negative(bd_addr_t addr){
5779     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5780     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5781 }
5782 
5783 /**
5784  * @brief SSP Passkey Response
5785  * @param addr
5786  * @param passkey
5787  * @return 0 if ok
5788  */
5789 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
5790     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5791     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5792     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5793 }
5794 
5795 /**
5796  * @brief Abort SSP Passkey Entry/Pairing
5797  * @param addr
5798  * @param pin
5799  * @return 0 if ok
5800  */
5801 int gap_ssp_passkey_negative(const bd_addr_t addr){
5802     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5803     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5804 }
5805 
5806 /**
5807  * @brief Accept SSP Numeric Comparison
5808  * @param addr
5809  * @param passkey
5810  * @return 0 if ok
5811  */
5812 int gap_ssp_confirmation_response(const bd_addr_t addr){
5813     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5814     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5815 }
5816 
5817 /**
5818  * @brief Abort SSP Numeric Comparison/Pairing
5819  * @param addr
5820  * @param pin
5821  * @return 0 if ok
5822  */
5823 int gap_ssp_confirmation_negative(const bd_addr_t addr){
5824     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5825     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5826 }
5827 
5828 /**
5829  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5830  * @param inquiry_mode see bluetooth_defines.h
5831  */
5832 void hci_set_inquiry_mode(inquiry_mode_t mode){
5833     hci_stack->inquiry_mode = mode;
5834 }
5835 
5836 /**
5837  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5838  */
5839 void hci_set_sco_voice_setting(uint16_t voice_setting){
5840     hci_stack->sco_voice_setting = voice_setting;
5841 }
5842 
5843 /**
5844  * @brief Get SCO Voice Setting
5845  * @return current voice setting
5846  */
5847 uint16_t hci_get_sco_voice_setting(void){
5848     return hci_stack->sco_voice_setting;
5849 }
5850 
5851 static int hci_have_usb_transport(void){
5852     if (!hci_stack->hci_transport) return 0;
5853     const char * transport_name = hci_stack->hci_transport->name;
5854     if (!transport_name) return 0;
5855     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5856 }
5857 
5858 /** @brief Get SCO packet length for current SCO Voice setting
5859  *  @note  Using SCO packets of the exact length is required for USB transfer
5860  *  @return Length of SCO packets in bytes (not audio frames)
5861  */
5862 int hci_get_sco_packet_length(void){
5863     int sco_packet_length = 0;
5864 
5865 #ifdef ENABLE_SCO_OVER_HCI
5866 
5867     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5868     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5869 
5870     if (hci_have_usb_transport()){
5871         // see Core Spec for H2 USB Transfer.
5872         // 3 byte SCO header + 24 bytes per connection
5873         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5874         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5875     } else {
5876         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5877         sco_packet_length = 3 + 60 * multiplier;
5878         // assert that it still fits inside an SCO buffer
5879         if (sco_packet_length > hci_stack->sco_data_packet_length){
5880             sco_packet_length = 3 + 60;
5881         }
5882     }
5883 #endif
5884     return sco_packet_length;
5885 }
5886 
5887 /**
5888 * @brief Sets the master/slave policy
5889 * @param policy (0: attempt to become master, 1: let connecting device decide)
5890 */
5891 void hci_set_master_slave_policy(uint8_t policy){
5892     hci_stack->master_slave_policy = policy;
5893 }
5894 
5895 #endif
5896 
5897 HCI_STATE hci_get_state(void){
5898     return hci_stack->state;
5899 }
5900 
5901 #ifdef ENABLE_CLASSIC
5902 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
5903     hci_stack->gap_classic_accept_callback = accept_callback;
5904 }
5905 #endif
5906 
5907 /**
5908  * @brief Set callback for Bluetooth Hardware Error
5909  */
5910 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5911     hci_stack->hardware_error_callback = fn;
5912 }
5913 
5914 void hci_disconnect_all(void){
5915     btstack_linked_list_iterator_t it;
5916     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5917     while (btstack_linked_list_iterator_has_next(&it)){
5918         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5919         if (con->state == SENT_DISCONNECT) continue;
5920         con->state = SEND_DISCONNECT;
5921     }
5922     hci_run();
5923 }
5924 
5925 uint16_t hci_get_manufacturer(void){
5926     return hci_stack->manufacturer;
5927 }
5928 
5929 #ifdef ENABLE_BLE
5930 
5931 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5932     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5933     if (!hci_con) return NULL;
5934     return &hci_con->sm_connection;
5935 }
5936 
5937 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5938 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5939 
5940 int gap_encryption_key_size(hci_con_handle_t con_handle){
5941     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5942     if (hci_connection == NULL) return 0;
5943     if (hci_is_le_connection(hci_connection)){
5944         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5945         if (sm_conn->sm_connection_encrypted) {
5946             return sm_conn->sm_actual_encryption_key_size;
5947         }
5948     }
5949 #ifdef ENABLE_CLASSIC
5950     else {
5951         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5952             return hci_connection->encryption_key_size;
5953         }
5954     }
5955 #endif
5956     return 0;
5957 }
5958 
5959 int gap_authenticated(hci_con_handle_t con_handle){
5960     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5961     if (hci_connection == NULL) return 0;
5962 
5963     switch (hci_connection->address_type){
5964         case BD_ADDR_TYPE_LE_PUBLIC:
5965         case BD_ADDR_TYPE_LE_RANDOM:
5966             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5967             return hci_connection->sm_connection.sm_connection_authenticated;
5968 #ifdef ENABLE_CLASSIC
5969         case BD_ADDR_TYPE_SCO:
5970         case BD_ADDR_TYPE_ACL:
5971             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5972 #endif
5973         default:
5974             return 0;
5975     }
5976 }
5977 
5978 int gap_secure_connection(hci_con_handle_t con_handle){
5979     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5980     if (hci_connection == NULL) return 0;
5981 
5982     switch (hci_connection->address_type){
5983         case BD_ADDR_TYPE_LE_PUBLIC:
5984         case BD_ADDR_TYPE_LE_RANDOM:
5985             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5986             return hci_connection->sm_connection.sm_connection_sc;
5987 #ifdef ENABLE_CLASSIC
5988         case BD_ADDR_TYPE_SCO:
5989         case BD_ADDR_TYPE_ACL:
5990             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5991 #endif
5992         default:
5993             return 0;
5994     }
5995 }
5996 
5997 bool gap_bonded(hci_con_handle_t con_handle){
5998 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5999 	if (hci_connection == NULL) return 0;
6000 
6001 #ifdef ENABLE_CLASSIC
6002 	link_key_t link_key;
6003 	link_key_type_t link_key_type;
6004 #endif
6005 	switch (hci_connection->address_type){
6006 		case BD_ADDR_TYPE_LE_PUBLIC:
6007 		case BD_ADDR_TYPE_LE_RANDOM:
6008 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6009 #ifdef ENABLE_CLASSIC
6010 		case BD_ADDR_TYPE_SCO:
6011 		case BD_ADDR_TYPE_ACL:
6012 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6013 #endif
6014 		default:
6015 			return false;
6016 	}
6017 }
6018 
6019 
6020 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6021     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6022     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6023     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6024     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6025     return sm_conn->sm_connection_authorization_state;
6026 }
6027 #endif
6028 
6029 #ifdef ENABLE_CLASSIC
6030 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){
6031     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6032     if (!conn) return GAP_CONNECTION_INVALID;
6033     conn->sniff_min_interval = sniff_min_interval;
6034     conn->sniff_max_interval = sniff_max_interval;
6035     conn->sniff_attempt = sniff_attempt;
6036     conn->sniff_timeout = sniff_timeout;
6037     hci_run();
6038     return 0;
6039 }
6040 
6041 /**
6042  * @brief Exit Sniff mode
6043  * @param con_handle
6044  @ @return 0 if ok
6045  */
6046 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6047     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6048     if (!conn) return GAP_CONNECTION_INVALID;
6049     conn->sniff_min_interval = 0xffff;
6050     hci_run();
6051     return 0;
6052 }
6053 #endif
6054 
6055 void hci_halting_defer(void){
6056     if (hci_stack->state != HCI_STATE_HALTING) return;
6057     switch (hci_stack->substate){
6058         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6059         case HCI_HALTING_CLOSE:
6060             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6061             break;
6062         default:
6063             break;
6064     }
6065 }
6066 
6067 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6068 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6069     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6070     if (le_device_db_index >= le_device_db_max_count()) return;
6071     uint8_t offset = le_device_db_index >> 3;
6072     uint8_t mask = 1 << (le_device_db_index & 7);
6073     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6074     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6075     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6076         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6077     }
6078 }
6079 
6080 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6081 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6082 	if (le_device_db_index >= le_device_db_max_count()) return;
6083 	uint8_t offset = le_device_db_index >> 3;
6084 	uint8_t mask = 1 << (le_device_db_index & 7);
6085 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6086 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6087 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6088 	}
6089 }
6090 
6091 uint8_t gap_load_resolving_list_from_le_device_db(void){
6092 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6093 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6094 	}
6095 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6096 		// restart le resolving list update
6097 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6098 	}
6099 	return ERROR_CODE_SUCCESS;
6100 }
6101 #endif
6102 
6103 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6104 void hci_setup_test_connections_fuzz(void){
6105     hci_connection_t * conn;
6106 
6107     // default address: 66:55:44:33:00:01
6108     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6109 
6110     // setup Controller info
6111     hci_stack->num_cmd_packets = 255;
6112     hci_stack->acl_packets_total_num = 255;
6113 
6114     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6115     addr[5] = 0x01;
6116     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6117     conn->con_handle = addr[5];
6118     conn->role  = HCI_ROLE_SLAVE;
6119     conn->state = RECEIVED_CONNECTION_REQUEST;
6120     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6121 
6122     // setup incoming Classic SCO connection with con handle 0x0002
6123     addr[5] = 0x02;
6124     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6125     conn->con_handle = addr[5];
6126     conn->role  = HCI_ROLE_SLAVE;
6127     conn->state = RECEIVED_CONNECTION_REQUEST;
6128     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6129 
6130     // setup ready Classic ACL connection with con handle 0x0003
6131     addr[5] = 0x03;
6132     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6133     conn->con_handle = addr[5];
6134     conn->role  = HCI_ROLE_SLAVE;
6135     conn->state = OPEN;
6136     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6137 
6138     // setup ready Classic SCO connection with con handle 0x0004
6139     addr[5] = 0x04;
6140     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6141     conn->con_handle = addr[5];
6142     conn->role  = HCI_ROLE_SLAVE;
6143     conn->state = OPEN;
6144     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6145 
6146     // setup ready LE ACL connection with con handle 0x005 and public address
6147     addr[5] = 0x05;
6148     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6149     conn->con_handle = addr[5];
6150     conn->role  = HCI_ROLE_SLAVE;
6151     conn->state = OPEN;
6152     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6153 }
6154 
6155 void hci_free_connections_fuzz(void){
6156     btstack_linked_list_iterator_t it;
6157     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6158     while (btstack_linked_list_iterator_has_next(&it)){
6159         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6160         btstack_linked_list_iterator_remove(&it);
6161         btstack_memory_hci_connection_free(con);
6162     }
6163 }
6164 void hci_simulate_working_fuzz(void){
6165     hci_init_done();
6166     hci_stack->num_cmd_packets = 255;
6167 }
6168 #endif
6169