xref: /btstack/src/hci.c (revision cfd54eb73cd29e7bf738f261fb454a84a1bb66b0)
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 void gap_delete_all_link_keys(void){
403     bd_addr_t  addr;
404     link_key_t link_key;
405     link_key_type_t type;
406     btstack_link_key_iterator_t it;
407     int ok = gap_link_key_iterator_init(&it);
408     if (!ok) {
409         log_error("could not initialize iterator");
410         return;
411     }
412     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
413         gap_drop_link_key_for_bd_addr(addr);
414     }
415     gap_link_key_iterator_done(&it);
416 }
417 
418 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
419     if (!hci_stack->link_key_db) return 0;
420     if (!hci_stack->link_key_db->iterator_init) return 0;
421     return hci_stack->link_key_db->iterator_init(it);
422 }
423 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){
424     if (!hci_stack->link_key_db) return 0;
425     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
426 }
427 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
428     if (!hci_stack->link_key_db) return;
429     hci_stack->link_key_db->iterator_done(it);
430 }
431 #endif
432 
433 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
434     switch (address_type){
435         case BD_ADDR_TYPE_LE_PUBLIC:
436         case BD_ADDR_TYPE_LE_RANDOM:
437         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
438         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
439             return true;
440         default:
441             return false;
442     }
443 }
444 
445 static int hci_is_le_connection(hci_connection_t * connection){
446     return hci_is_le_connection_type(connection->address_type);
447 }
448 
449 /**
450  * count connections
451  */
452 static int nr_hci_connections(void){
453     int count = 0;
454     btstack_linked_item_t *it;
455     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
456         count++;
457     }
458     return count;
459 }
460 
461 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
462 
463     unsigned int num_packets_sent_classic = 0;
464     unsigned int num_packets_sent_le = 0;
465 
466     btstack_linked_item_t *it;
467     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
468         hci_connection_t * connection = (hci_connection_t *) it;
469         if (hci_is_le_connection(connection)){
470             num_packets_sent_le += connection->num_packets_sent;
471         }
472         if (connection->address_type == BD_ADDR_TYPE_ACL){
473             num_packets_sent_classic += connection->num_packets_sent;
474         }
475     }
476     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
477     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
478     int free_slots_le = 0;
479 
480     if (free_slots_classic < 0){
481         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);
482         return 0;
483     }
484 
485     if (hci_stack->le_acl_packets_total_num){
486         // if we have LE slots, they are used
487         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
488         if (free_slots_le < 0){
489             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);
490             return 0;
491         }
492     } else {
493         // otherwise, classic slots are used for LE, too
494         free_slots_classic -= num_packets_sent_le;
495         if (free_slots_classic < 0){
496             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);
497             return 0;
498         }
499     }
500 
501     switch (address_type){
502         case BD_ADDR_TYPE_UNKNOWN:
503             log_error("hci_number_free_acl_slots: unknown address type");
504             return 0;
505 
506         case BD_ADDR_TYPE_ACL:
507             return free_slots_classic;
508 
509         default:
510            if (hci_stack->le_acl_packets_total_num){
511                return free_slots_le;
512            }
513            return free_slots_classic;
514     }
515 }
516 
517 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
518     // get connection type
519     hci_connection_t * connection = hci_connection_for_handle(con_handle);
520     if (!connection){
521         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
522         return 0;
523     }
524     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
525 }
526 
527 #ifdef ENABLE_CLASSIC
528 static int hci_number_free_sco_slots(void){
529     unsigned int num_sco_packets_sent  = 0;
530     btstack_linked_item_t *it;
531     if (hci_stack->synchronous_flow_control_enabled){
532         // explicit flow control
533         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
534             hci_connection_t * connection = (hci_connection_t *) it;
535             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
536             num_sco_packets_sent += connection->num_packets_sent;
537         }
538         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
539             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
540             return 0;
541         }
542         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
543     } else {
544         // implicit flow control -- TODO
545         int num_ready = 0;
546         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
547             hci_connection_t * connection = (hci_connection_t *) it;
548             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
549             if (connection->sco_tx_ready == 0) continue;
550             num_ready++;
551         }
552         return num_ready;
553     }
554 }
555 #endif
556 
557 // only used to send HCI Host Number Completed Packets
558 static int hci_can_send_comand_packet_transport(void){
559     if (hci_stack->hci_packet_buffer_reserved) return 0;
560 
561     // check for async hci transport implementations
562     if (hci_stack->hci_transport->can_send_packet_now){
563         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
564             return 0;
565         }
566     }
567     return 1;
568 }
569 
570 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
571 int hci_can_send_command_packet_now(void){
572     if (hci_can_send_comand_packet_transport() == 0) return 0;
573     return hci_stack->num_cmd_packets > 0u;
574 }
575 
576 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
577     // check for async hci transport implementations
578     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
579     return hci_stack->hci_transport->can_send_packet_now(packet_type);
580 }
581 
582 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
583     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
584     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
585 }
586 
587 int hci_can_send_acl_le_packet_now(void){
588     if (hci_stack->hci_packet_buffer_reserved) return 0;
589     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
590 }
591 
592 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
593     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
594     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
595 }
596 
597 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
598     if (hci_stack->hci_packet_buffer_reserved) return 0;
599     return hci_can_send_prepared_acl_packet_now(con_handle);
600 }
601 
602 #ifdef ENABLE_CLASSIC
603 int hci_can_send_acl_classic_packet_now(void){
604     if (hci_stack->hci_packet_buffer_reserved) return 0;
605     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
606 }
607 
608 int hci_can_send_prepared_sco_packet_now(void){
609     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
610     if (hci_have_usb_transport()){
611         return hci_stack->sco_can_send_now;
612     } else {
613         return hci_number_free_sco_slots() > 0;
614     }
615 }
616 
617 int hci_can_send_sco_packet_now(void){
618     if (hci_stack->hci_packet_buffer_reserved) return 0;
619     return hci_can_send_prepared_sco_packet_now();
620 }
621 
622 void hci_request_sco_can_send_now_event(void){
623     hci_stack->sco_waiting_for_can_send_now = 1;
624     hci_notify_if_sco_can_send_now();
625 }
626 #endif
627 
628 // used for internal checks in l2cap.c
629 int hci_is_packet_buffer_reserved(void){
630     return hci_stack->hci_packet_buffer_reserved;
631 }
632 
633 // reserves outgoing packet buffer. @returns 1 if successful
634 int hci_reserve_packet_buffer(void){
635     if (hci_stack->hci_packet_buffer_reserved) {
636         log_error("hci_reserve_packet_buffer called but buffer already reserved");
637         return 0;
638     }
639     hci_stack->hci_packet_buffer_reserved = 1;
640     return 1;
641 }
642 
643 void hci_release_packet_buffer(void){
644     hci_stack->hci_packet_buffer_reserved = 0;
645 }
646 
647 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
648 static int hci_transport_synchronous(void){
649     return hci_stack->hci_transport->can_send_packet_now == NULL;
650 }
651 
652 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
653 
654     // 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);
655 
656     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
657     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
658     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
659         max_acl_data_packet_length = hci_stack->le_data_packets_length;
660     }
661 
662 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
663     if (hci_is_le_connection(connection)){
664         max_acl_data_packet_length = connection->le_max_tx_octets;
665     }
666 #endif
667 
668     log_debug("hci_send_acl_packet_fragments entered");
669 
670     int err;
671     // multiple packets could be send on a synchronous HCI transport
672     while (true){
673 
674         log_debug("hci_send_acl_packet_fragments loop entered");
675 
676         // get current data
677         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
678         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
679         int more_fragments = 0;
680 
681         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
682         if (current_acl_data_packet_length > max_acl_data_packet_length){
683             more_fragments = 1;
684             current_acl_data_packet_length = max_acl_data_packet_length;
685         }
686 
687         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
688         if (acl_header_pos > 0u){
689             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
690             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
691             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
692         }
693 
694         // update header len
695         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
696 
697         // count packet
698         connection->num_packets_sent++;
699         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
700 
701         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
702         if (more_fragments){
703             // update start of next fragment to send
704             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
705         } else {
706             // done
707             hci_stack->acl_fragmentation_pos = 0;
708             hci_stack->acl_fragmentation_total_size = 0;
709         }
710 
711         // send packet
712         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
713         const int size = current_acl_data_packet_length + 4;
714         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
715         hci_stack->acl_fragmentation_tx_active = 1;
716         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
717 
718         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
719 
720         // done yet?
721         if (!more_fragments) break;
722 
723         // can send more?
724         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
725     }
726 
727     log_debug("hci_send_acl_packet_fragments loop over");
728 
729     // release buffer now for synchronous transport
730     if (hci_transport_synchronous()){
731         hci_stack->acl_fragmentation_tx_active = 0;
732         hci_release_packet_buffer();
733         hci_emit_transport_packet_sent();
734     }
735 
736     return err;
737 }
738 
739 // pre: caller has reserved the packet buffer
740 int hci_send_acl_packet_buffer(int size){
741 
742     // log_info("hci_send_acl_packet_buffer size %u", size);
743 
744     if (!hci_stack->hci_packet_buffer_reserved) {
745         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
746         return 0;
747     }
748 
749     uint8_t * packet = hci_stack->hci_packet_buffer;
750     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
751 
752     // check for free places on Bluetooth module
753     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
754         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
755         hci_release_packet_buffer();
756         hci_emit_transport_packet_sent();
757         return BTSTACK_ACL_BUFFERS_FULL;
758     }
759 
760     hci_connection_t *connection = hci_connection_for_handle( con_handle);
761     if (!connection) {
762         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
763         hci_release_packet_buffer();
764         hci_emit_transport_packet_sent();
765         return 0;
766     }
767 
768 #ifdef ENABLE_CLASSIC
769     hci_connection_timestamp(connection);
770 #endif
771 
772     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
773 
774     // setup data
775     hci_stack->acl_fragmentation_total_size = size;
776     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
777 
778     return hci_send_acl_packet_fragments(connection);
779 }
780 
781 #ifdef ENABLE_CLASSIC
782 // pre: caller has reserved the packet buffer
783 int hci_send_sco_packet_buffer(int size){
784 
785     // log_info("hci_send_acl_packet_buffer size %u", size);
786 
787     if (!hci_stack->hci_packet_buffer_reserved) {
788         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
789         return 0;
790     }
791 
792     uint8_t * packet = hci_stack->hci_packet_buffer;
793 
794     // skip checks in loopback mode
795     if (!hci_stack->loopback_mode){
796         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
797 
798         // check for free places on Bluetooth module
799         if (!hci_can_send_prepared_sco_packet_now()) {
800             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
801             hci_release_packet_buffer();
802             hci_emit_transport_packet_sent();
803             return BTSTACK_ACL_BUFFERS_FULL;
804         }
805 
806         // track send packet in connection struct
807         hci_connection_t *connection = hci_connection_for_handle( con_handle);
808         if (!connection) {
809             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
810             hci_release_packet_buffer();
811             hci_emit_transport_packet_sent();
812             return 0;
813         }
814 
815         if (hci_have_usb_transport()){
816             // token used
817             hci_stack->sco_can_send_now = 0;
818         } else {
819             if (hci_stack->synchronous_flow_control_enabled){
820                 connection->num_packets_sent++;
821             } else {
822                 connection->sco_tx_ready--;
823             }
824         }
825     }
826 
827     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
828     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
829 
830     if (hci_transport_synchronous()){
831         hci_release_packet_buffer();
832         hci_emit_transport_packet_sent();
833     }
834 
835     return err;
836 }
837 #endif
838 
839 static void acl_handler(uint8_t *packet, uint16_t size){
840 
841     // get info
842     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
843     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
844     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
845     uint16_t acl_length         = READ_ACL_LENGTH(packet);
846 
847     // ignore non-registered handle
848     if (!conn){
849         log_error("acl_handler called with non-registered handle %u!" , con_handle);
850         return;
851     }
852 
853     // assert packet is complete
854     if ((acl_length + 4u) != size){
855         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
856         return;
857     }
858 
859 #ifdef ENABLE_CLASSIC
860     // update idle timestamp
861     hci_connection_timestamp(conn);
862 #endif
863 
864 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
865     hci_stack->host_completed_packets = 1;
866     conn->num_packets_completed++;
867 #endif
868 
869     // handle different packet types
870     switch (acl_flags & 0x03u) {
871 
872         case 0x01: // continuation fragment
873 
874             // sanity checks
875             if (conn->acl_recombination_pos == 0u) {
876                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
877                 return;
878             }
879             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
880                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
881                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
882                 conn->acl_recombination_pos = 0;
883                 return;
884             }
885 
886             // append fragment payload (header already stored)
887             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
888                          &packet[4], acl_length);
889             conn->acl_recombination_pos += acl_length;
890 
891             // forward complete L2CAP packet if complete.
892             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
893                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
894                 // reset recombination buffer
895                 conn->acl_recombination_length = 0;
896                 conn->acl_recombination_pos = 0;
897             }
898             break;
899 
900         case 0x02: { // first fragment
901 
902             // sanity check
903             if (conn->acl_recombination_pos) {
904                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
905                 conn->acl_recombination_pos = 0;
906             }
907 
908             // peek into L2CAP packet!
909             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
910 
911             // compare fragment size to L2CAP packet size
912             if (acl_length >= (l2cap_length + 4u)){
913                 // forward fragment as L2CAP packet
914                 hci_emit_acl_packet(packet, acl_length + 4u);
915             } else {
916 
917                 if (acl_length > HCI_ACL_BUFFER_SIZE){
918                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
919                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
920                     return;
921                 }
922 
923                 // store first fragment and tweak acl length for complete package
924                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
925                              packet, acl_length + 4u);
926                 conn->acl_recombination_pos    = acl_length + 4u;
927                 conn->acl_recombination_length = l2cap_length;
928                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
929             }
930             break;
931 
932         }
933         default:
934             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
935             return;
936     }
937 
938     // execute main loop
939     hci_run();
940 }
941 
942 static void hci_shutdown_connection(hci_connection_t *conn){
943     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
944 
945 #ifdef ENABLE_CLASSIC
946 #ifdef ENABLE_SCO_OVER_HCI
947     int addr_type = conn->address_type;
948 #endif
949 #endif
950 
951     btstack_run_loop_remove_timer(&conn->timeout);
952 
953     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
954     btstack_memory_hci_connection_free( conn );
955 
956     // now it's gone
957     hci_emit_nr_connections_changed();
958 
959 #ifdef ENABLE_CLASSIC
960 #ifdef ENABLE_SCO_OVER_HCI
961     // update SCO
962     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
963         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
964     }
965 #endif
966 #endif
967 }
968 
969 #ifdef ENABLE_CLASSIC
970 
971 static const uint16_t packet_type_sizes[] = {
972     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
973     HCI_ACL_DH1_SIZE, 0, 0, 0,
974     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
975     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
976 };
977 static const uint8_t  packet_type_feature_requirement_bit[] = {
978      0, // 3 slot packets
979      1, // 5 slot packets
980     25, // EDR 2 mpbs
981     26, // EDR 3 mbps
982     39, // 3 slot EDR packts
983     40, // 5 slot EDR packet
984 };
985 static const uint16_t packet_type_feature_packet_mask[] = {
986     0x0f00, // 3 slot packets
987     0xf000, // 5 slot packets
988     0x1102, // EDR 2 mpbs
989     0x2204, // EDR 3 mbps
990     0x0300, // 3 slot EDR packts
991     0x3000, // 5 slot EDR packet
992 };
993 
994 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
995     // enable packet types based on size
996     uint16_t packet_types = 0;
997     unsigned int i;
998     for (i=0;i<16;i++){
999         if (packet_type_sizes[i] == 0) continue;
1000         if (packet_type_sizes[i] <= buffer_size){
1001             packet_types |= 1 << i;
1002         }
1003     }
1004     // disable packet types due to missing local supported features
1005     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1006         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1007         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1008         if (feature_set) continue;
1009         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1010         packet_types &= ~packet_type_feature_packet_mask[i];
1011     }
1012     // flip bits for "may not be used"
1013     packet_types ^= 0x3306;
1014     return packet_types;
1015 }
1016 
1017 uint16_t hci_usable_acl_packet_types(void){
1018     return hci_stack->packet_types;
1019 }
1020 #endif
1021 
1022 uint8_t* hci_get_outgoing_packet_buffer(void){
1023     // hci packet buffer is >= acl data packet length
1024     return hci_stack->hci_packet_buffer;
1025 }
1026 
1027 uint16_t hci_max_acl_data_packet_length(void){
1028     return hci_stack->acl_data_packet_length;
1029 }
1030 
1031 #ifdef ENABLE_CLASSIC
1032 int hci_extended_sco_link_supported(void){
1033     // No. 31, byte 3, bit 7
1034     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1035 }
1036 #endif
1037 
1038 int hci_non_flushable_packet_boundary_flag_supported(void){
1039     // No. 54, byte 6, bit 6
1040     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1041 }
1042 
1043 static int gap_ssp_supported(void){
1044     // No. 51, byte 6, bit 3
1045     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1046 }
1047 
1048 static int hci_classic_supported(void){
1049 #ifdef ENABLE_CLASSIC
1050     // No. 37, byte 4, bit 5, = No BR/EDR Support
1051     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1052 #else
1053     return 0;
1054 #endif
1055 }
1056 
1057 static int hci_le_supported(void){
1058 #ifdef ENABLE_BLE
1059     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1060     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1061 #else
1062     return 0;
1063 #endif
1064 }
1065 
1066 #ifdef ENABLE_BLE
1067 
1068 /**
1069  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1070  */
1071 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1072     *addr_type = hci_stack->le_own_addr_type;
1073     if (hci_stack->le_own_addr_type){
1074         (void)memcpy(addr, hci_stack->le_random_address, 6);
1075     } else {
1076         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1077     }
1078 }
1079 
1080 #ifdef ENABLE_LE_CENTRAL
1081 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1082 
1083     int offset = 3;
1084     int num_reports = packet[offset];
1085     offset += 1;
1086 
1087     int i;
1088     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1089     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1090     for (i=0; (i<num_reports) && (offset < size);i++){
1091         // sanity checks on data_length:
1092         uint8_t data_length = packet[offset + 8];
1093         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1094         if ((offset + 9u + data_length + 1u) > size)    return;
1095         // setup event
1096         uint8_t event_size = 10u + data_length;
1097         int pos = 0;
1098         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1099         event[pos++] = event_size;
1100         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1101         offset += 8;
1102         pos += 8;
1103         event[pos++] = packet[offset + 1 + data_length]; // rssi
1104         event[pos++] = data_length;
1105         offset++;
1106         (void)memcpy(&event[pos], &packet[offset], data_length);
1107         pos +=    data_length;
1108         offset += data_length + 1u; // rssi
1109         hci_emit_event(event, pos, 1);
1110     }
1111 }
1112 #endif
1113 #endif
1114 
1115 #ifdef ENABLE_BLE
1116 #ifdef ENABLE_LE_PERIPHERAL
1117 static void hci_update_advertisements_enabled_for_current_roles(void){
1118     if (hci_stack->le_advertisements_enabled){
1119         // get number of active le slave connections
1120         int num_slave_connections = 0;
1121         btstack_linked_list_iterator_t it;
1122         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1123         while (btstack_linked_list_iterator_has_next(&it)){
1124             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1125             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1126             if (con->state != OPEN) continue;
1127             if (con->role  != HCI_ROLE_SLAVE) continue;
1128             if (!hci_is_le_connection(con)) continue;
1129             num_slave_connections++;
1130         }
1131         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1132         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1133     } else {
1134         hci_stack->le_advertisements_enabled_for_current_roles = false;
1135     }
1136 }
1137 #endif
1138 #endif
1139 
1140 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1141 
1142 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1143     if (!hci_stack->config) return 0;
1144     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1145     // Limit baud rate for Broadcom chipsets to 3 mbps
1146     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1147         baud_rate = 3000000;
1148     }
1149     return baud_rate;
1150 }
1151 
1152 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1153     UNUSED(ds);
1154 
1155     switch (hci_stack->substate){
1156         case HCI_INIT_W4_SEND_RESET:
1157             log_info("Resend HCI Reset");
1158             hci_stack->substate = HCI_INIT_SEND_RESET;
1159             hci_stack->num_cmd_packets = 1;
1160             hci_run();
1161             break;
1162         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1163             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1164             if (hci_stack->hci_transport->reset_link){
1165                 hci_stack->hci_transport->reset_link();
1166             }
1167 
1168             /* fall through */
1169 
1170         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1171             log_info("Resend HCI Reset - CSR Warm Boot");
1172             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1173             hci_stack->num_cmd_packets = 1;
1174             hci_run();
1175             break;
1176         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1177             if (hci_stack->hci_transport->set_baudrate){
1178                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1179                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1180                 hci_stack->hci_transport->set_baudrate(baud_rate);
1181             }
1182             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1183             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1184                 if (hci_stack->hci_transport->reset_link){
1185                     log_info("Link Reset");
1186                     hci_stack->hci_transport->reset_link();
1187                 }
1188                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1189                 hci_run();
1190             }
1191             break;
1192         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1193             // otherwise continue
1194             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1195             hci_send_cmd(&hci_read_local_supported_commands);
1196             break;
1197         default:
1198             break;
1199     }
1200 }
1201 #endif
1202 
1203 static void hci_initializing_next_state(void){
1204     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1205 }
1206 
1207 // assumption: hci_can_send_command_packet_now() == true
1208 static void hci_initializing_run(void){
1209     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1210     switch (hci_stack->substate){
1211         case HCI_INIT_SEND_RESET:
1212             hci_state_reset();
1213 
1214 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1215             // prepare reset if command complete not received in 100ms
1216             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1217             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1218             btstack_run_loop_add_timer(&hci_stack->timeout);
1219 #endif
1220             // send command
1221             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1222             hci_send_cmd(&hci_reset);
1223             break;
1224         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1225             hci_send_cmd(&hci_read_local_version_information);
1226             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1227             break;
1228         case HCI_INIT_SEND_READ_LOCAL_NAME:
1229             hci_send_cmd(&hci_read_local_name);
1230             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1231             break;
1232 
1233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1234         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1235             hci_state_reset();
1236             // prepare reset if command complete not received in 100ms
1237             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1238             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1239             btstack_run_loop_add_timer(&hci_stack->timeout);
1240             // send command
1241             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1242             hci_send_cmd(&hci_reset);
1243             break;
1244         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1245             hci_state_reset();
1246             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1247             hci_send_cmd(&hci_reset);
1248             break;
1249         case HCI_INIT_SEND_BAUD_CHANGE: {
1250             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1251             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1252             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1253             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1254             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1255             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1256             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1257             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1258                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1259                 btstack_run_loop_add_timer(&hci_stack->timeout);
1260             }
1261             break;
1262         }
1263         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1264             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1265             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1266             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1267             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1268             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1269             break;
1270         }
1271         case HCI_INIT_CUSTOM_INIT:
1272             // Custom initialization
1273             if (hci_stack->chipset && hci_stack->chipset->next_command){
1274                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1275                 int send_cmd = 0;
1276                 switch (hci_stack->chipset_result){
1277                     case BTSTACK_CHIPSET_VALID_COMMAND:
1278                         send_cmd = 1;
1279                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1280                         break;
1281                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1282                         send_cmd = 1;
1283                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1284                         log_info("CSR Warm Boot");
1285                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1286                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1287                         btstack_run_loop_add_timer(&hci_stack->timeout);
1288                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1289                             && hci_stack->config
1290                             && hci_stack->chipset
1291                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1292                             && hci_stack->hci_transport->set_baudrate
1293                             && hci_transport_uart_get_main_baud_rate()){
1294                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1295                         } else {
1296                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1297                         }
1298                         break;
1299                     default:
1300                         break;
1301                 }
1302 
1303                 if (send_cmd){
1304                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1305                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1306                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1307                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1308                     break;
1309                 }
1310                 log_info("Init script done");
1311 
1312                 // Init script download on Broadcom chipsets causes:
1313                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1314                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1315                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1316 
1317                     // - baud rate to reset, restore UART baud rate if needed
1318                     int need_baud_change = hci_stack->config
1319                         && hci_stack->chipset
1320                         && hci_stack->chipset->set_baudrate_command
1321                         && hci_stack->hci_transport->set_baudrate
1322                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1323                     if (need_baud_change) {
1324                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1325                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1326                         hci_stack->hci_transport->set_baudrate(baud_rate);
1327                     }
1328 
1329                     uint16_t bcm_delay_ms = 300;
1330                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1331                     //   -> Work around: wait here.
1332                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1333                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1334                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1335                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1336                     btstack_run_loop_add_timer(&hci_stack->timeout);
1337                     break;
1338                 }
1339             }
1340             // otherwise continue
1341             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1342             hci_send_cmd(&hci_read_local_supported_commands);
1343             break;
1344         case HCI_INIT_SET_BD_ADDR:
1345             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1346             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1347             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1348             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1349             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1350             break;
1351 #endif
1352 
1353         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1354             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1355             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1356             hci_send_cmd(&hci_read_local_supported_commands);
1357             break;
1358         case HCI_INIT_READ_BD_ADDR:
1359             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1360             hci_send_cmd(&hci_read_bd_addr);
1361             break;
1362         case HCI_INIT_READ_BUFFER_SIZE:
1363             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1364             hci_send_cmd(&hci_read_buffer_size);
1365             break;
1366         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1367             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1368             hci_send_cmd(&hci_read_local_supported_features);
1369             break;
1370 
1371 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1372         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1373             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1374             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1375             break;
1376         case HCI_INIT_HOST_BUFFER_SIZE:
1377             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1378             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1379                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1380             break;
1381 #endif
1382 
1383         case HCI_INIT_SET_EVENT_MASK:
1384             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1385             if (hci_le_supported()){
1386                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1387             } else {
1388                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1389                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1390             }
1391             break;
1392 
1393 #ifdef ENABLE_CLASSIC
1394         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1395             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1396             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1397             break;
1398         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1399             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1400             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1401             break;
1402         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1403             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1404             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1405             break;
1406         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1407             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1408             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1409             break;
1410         case HCI_INIT_WRITE_LOCAL_NAME: {
1411             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1412             hci_reserve_packet_buffer();
1413             uint8_t * packet = hci_stack->hci_packet_buffer;
1414             // construct HCI Command and send
1415             uint16_t opcode = hci_write_local_name.opcode;
1416             hci_stack->last_cmd_opcode = opcode;
1417             packet[0] = opcode & 0xff;
1418             packet[1] = opcode >> 8;
1419             packet[2] = DEVICE_NAME_LEN;
1420             memset(&packet[3], 0, DEVICE_NAME_LEN);
1421             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1422             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1423             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1424             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1425             // expand '00:00:00:00:00:00' in name with bd_addr
1426             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1427             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1428             break;
1429         }
1430         case HCI_INIT_WRITE_EIR_DATA: {
1431             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1432             hci_reserve_packet_buffer();
1433             uint8_t * packet = hci_stack->hci_packet_buffer;
1434             // construct HCI Command in-place and send
1435             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1436             hci_stack->last_cmd_opcode = opcode;
1437             uint16_t offset = 0;
1438             packet[offset++] = opcode & 0xff;
1439             packet[offset++] = opcode >> 8;
1440             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1441             packet[offset++] = 0;  // FEC not required
1442             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1443             if (hci_stack->eir_data){
1444                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1445                 ad_context_t context;
1446                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1447                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1448                     uint8_t size        = ad_iterator_get_data_len(&context);
1449                     const uint8_t *data = ad_iterator_get_data(&context);
1450                     // copy item
1451                     packet[offset++] = size + 1;
1452                     packet[offset++] = data_type;
1453                     memcpy(&packet[offset], data, size);
1454                     // update name item
1455                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1456                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1457                     }
1458                     offset += size;
1459                 }
1460             } else {
1461                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1462                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1463                 packet[offset++] = bytes_to_copy + 1;
1464                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1465                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1466                 // expand '00:00:00:00:00:00' in name with bd_addr
1467                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1468             }
1469             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1470             break;
1471         }
1472         case HCI_INIT_WRITE_INQUIRY_MODE:
1473             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1474             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1475             break;
1476         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1477             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1478             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1479             break;
1480         case HCI_INIT_WRITE_SCAN_ENABLE:
1481             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1482             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1483             break;
1484         // only sent if ENABLE_SCO_OVER_HCI is defined
1485         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1487             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1488             break;
1489         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1490             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1491             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1492             break;
1493         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1494         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1495             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1496             log_info("BCM: Route SCO data via HCI transport");
1497             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1498             break;
1499 
1500 #endif
1501 #ifdef ENABLE_BLE
1502         // LE INIT
1503         case HCI_INIT_LE_READ_BUFFER_SIZE:
1504             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1505             hci_send_cmd(&hci_le_read_buffer_size);
1506             break;
1507         case HCI_INIT_LE_SET_EVENT_MASK:
1508             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1509             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1510             break;
1511         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1512             // LE Supported Host = 1, Simultaneous Host = 0
1513             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1514             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1515             break;
1516 #endif
1517 
1518 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1519         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1520             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1521             hci_send_cmd(&hci_le_read_maximum_data_length);
1522             break;
1523         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1524             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1525             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1526             break;
1527 #endif
1528 
1529 #ifdef ENABLE_LE_CENTRAL
1530         case HCI_INIT_READ_WHITE_LIST_SIZE:
1531             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1532             hci_send_cmd(&hci_le_read_white_list_size);
1533             break;
1534         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1535             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1536             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);
1537             break;
1538 #endif
1539         default:
1540             return;
1541     }
1542 }
1543 
1544 static void hci_init_done(void){
1545     // done. tell the app
1546     log_info("hci_init_done -> HCI_STATE_WORKING");
1547     hci_stack->state = HCI_STATE_WORKING;
1548     hci_emit_state();
1549     hci_run();
1550 }
1551 
1552 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1553     bool command_completed = false;
1554     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1555         uint16_t opcode = little_endian_read_16(packet,3);
1556         if (opcode == hci_stack->last_cmd_opcode){
1557             command_completed = true;
1558             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1559         } else {
1560             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1561         }
1562     }
1563 
1564     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1565         uint8_t  status = packet[2];
1566         uint16_t opcode = little_endian_read_16(packet,4);
1567         if (opcode == hci_stack->last_cmd_opcode){
1568             if (status){
1569                 command_completed = true;
1570                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1571             } else {
1572                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1573             }
1574         } else {
1575             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1576         }
1577     }
1578 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1579     // Vendor == CSR
1580     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1581         // TODO: track actual command
1582         command_completed = true;
1583     }
1584 
1585     // Vendor == Toshiba
1586     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1587         // TODO: track actual command
1588         command_completed = true;
1589         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1590         hci_stack->num_cmd_packets = 1;
1591     }
1592 #endif
1593 
1594     return command_completed;
1595 }
1596 
1597 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1598 
1599     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1600 
1601     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1602 
1603 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1604 
1605     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1606     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1607     //
1608     // HCI Reset
1609     // Timeout 100 ms
1610     // HCI Reset
1611     // Command Complete Reset
1612     // HCI Read Local Version Information
1613     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1614     // hang...
1615     //
1616     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1617     if (!command_completed
1618             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1619             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1620 
1621         uint16_t opcode = little_endian_read_16(packet,3);
1622         if (opcode == hci_reset.opcode){
1623             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1624             return;
1625         }
1626     }
1627 
1628     // CSR & H5
1629     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1630     if (!command_completed
1631             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1632             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1633 
1634         uint16_t opcode = little_endian_read_16(packet,3);
1635         if (opcode == hci_reset.opcode){
1636             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1637             return;
1638         }
1639     }
1640 
1641     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1642     // fix: Correct substate and behave as command below
1643     if (command_completed){
1644         switch (hci_stack->substate){
1645             case HCI_INIT_SEND_RESET:
1646                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1647                 break;
1648             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1649                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1650                 break;
1651             default:
1652                 break;
1653         }
1654     }
1655 
1656 #endif
1657 
1658     if (!command_completed) return;
1659 
1660     bool need_baud_change = false;
1661     bool need_addr_change = false;
1662 
1663 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1664     need_baud_change = hci_stack->config
1665                         && hci_stack->chipset
1666                         && hci_stack->chipset->set_baudrate_command
1667                         && hci_stack->hci_transport->set_baudrate
1668                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1669 
1670     need_addr_change = hci_stack->custom_bd_addr_set
1671                         && hci_stack->chipset
1672                         && hci_stack->chipset->set_bd_addr_command;
1673 #endif
1674 
1675     switch(hci_stack->substate){
1676 
1677 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1678         case HCI_INIT_SEND_RESET:
1679             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1680             // fix: just correct substate and behave as command below
1681             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1682             btstack_run_loop_remove_timer(&hci_stack->timeout);
1683             break;
1684         case HCI_INIT_W4_SEND_RESET:
1685             btstack_run_loop_remove_timer(&hci_stack->timeout);
1686             break;
1687         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1688             log_info("Received local name, need baud change %d", (int) need_baud_change);
1689             if (need_baud_change){
1690                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1691                 return;
1692             }
1693             // skip baud change
1694             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1695             return;
1696         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1697             // for STLC2500D, baud rate change already happened.
1698             // for others, baud rate gets changed now
1699             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1700                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1701                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1702                 hci_stack->hci_transport->set_baudrate(baud_rate);
1703             }
1704             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1705             return;
1706         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1707             btstack_run_loop_remove_timer(&hci_stack->timeout);
1708             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1709             return;
1710         case HCI_INIT_W4_CUSTOM_INIT:
1711             // repeat custom init
1712             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1713             return;
1714 #else
1715         case HCI_INIT_W4_SEND_RESET:
1716             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1717             return ;
1718 #endif
1719 
1720         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1721             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1722               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1723                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1724                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1725                 return;
1726             }
1727             if (need_addr_change){
1728                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1729                 return;
1730             }
1731             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1732             return;
1733 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1734         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1735             if (need_baud_change){
1736                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1737                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1738                 hci_stack->hci_transport->set_baudrate(baud_rate);
1739             }
1740             if (need_addr_change){
1741                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1742                 return;
1743             }
1744             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1745             return;
1746         case HCI_INIT_W4_SET_BD_ADDR:
1747             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1748             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1749             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1750                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1751                 return;
1752             }
1753             // skipping st warm boot
1754             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1755             return;
1756         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1757             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1758             return;
1759 #endif
1760         case HCI_INIT_W4_READ_BD_ADDR:
1761             // only read buffer size if supported
1762             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1763                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1764                 return;
1765             }
1766             // skipping read buffer size
1767             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1768             return;
1769         case HCI_INIT_W4_SET_EVENT_MASK:
1770             // skip Classic init commands for LE only chipsets
1771             if (!hci_classic_supported()){
1772 #ifdef ENABLE_BLE
1773                 if (hci_le_supported()){
1774                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1775                     return;
1776                 }
1777 #endif
1778                 log_error("Neither BR/EDR nor LE supported");
1779                 hci_init_done();
1780                 return;
1781             }
1782             if (!gap_ssp_supported()){
1783                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1784                 return;
1785             }
1786             break;
1787 #ifdef ENABLE_BLE
1788         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1789             // skip write le host if not supported (e.g. on LE only EM9301)
1790             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1791             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1792             return;
1793 
1794 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1795         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1796             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1797             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1798                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1799                 return;
1800             }
1801             // explicit fall through to reduce repetitions
1802 
1803 #ifdef ENABLE_LE_CENTRAL
1804             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1805 #else
1806             hci_init_done();
1807 #endif
1808             return;
1809 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1810 
1811 #endif  /* ENABLE_BLE */
1812 
1813         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1814             // skip write secure connections host support if not supported or disabled
1815             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1816                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1817                 return;
1818             }
1819             break;
1820 
1821 #ifdef ENABLE_SCO_OVER_HCI
1822         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1823             // skip write synchronous flow control if not supported
1824             if (hci_stack->local_supported_commands[0] & 0x04) break;
1825             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1826 
1827             /* fall through */
1828 
1829         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1830             // skip write default erroneous data reporting if not supported
1831             if (hci_stack->local_supported_commands[0] & 0x08) break;
1832             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1833 
1834             /* fall through */
1835 
1836         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1837             // skip bcm set sco pcm config on non-Broadcom chipsets
1838             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1839             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1840 
1841             /* fall through */
1842 
1843         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1844             if (!hci_le_supported()){
1845                 // SKIP LE init for Classic only configuration
1846                 hci_init_done();
1847                 return;
1848             }
1849             break;
1850 
1851 #else /* !ENABLE_SCO_OVER_HCI */
1852 
1853         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1854 #ifdef ENABLE_BLE
1855             if (hci_le_supported()){
1856                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1857                 return;
1858             }
1859 #endif
1860             // SKIP LE init for Classic only configuration
1861             hci_init_done();
1862             return;
1863 #endif /* ENABLE_SCO_OVER_HCI */
1864 
1865 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1866 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1867         // Response to command before init done state -> init done
1868         case (HCI_INIT_DONE-1):
1869             hci_init_done();
1870             return;
1871 #endif
1872 
1873         default:
1874             break;
1875     }
1876     hci_initializing_next_state();
1877 }
1878 
1879 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1880     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1881     bd_addr_t bd_address;
1882     (void)memcpy(&bd_address, conn->address, 6);
1883 
1884 #ifdef ENABLE_CLASSIC
1885     // cache needed data
1886     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1887 #endif
1888 
1889     // connection failed, remove entry
1890     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1891     btstack_memory_hci_connection_free( conn );
1892 
1893 #ifdef ENABLE_CLASSIC
1894     // notify client if dedicated bonding
1895     if (notify_dedicated_bonding_failed){
1896         log_info("hci notify_dedicated_bonding_failed");
1897         hci_emit_dedicated_bonding_result(bd_address, status);
1898     }
1899 
1900     // if authentication error, also delete link key
1901     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1902         gap_drop_link_key_for_bd_addr(bd_address);
1903     }
1904 #else
1905     UNUSED(status);
1906 #endif
1907 }
1908 
1909 #ifdef ENABLE_CLASSIC
1910 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1911     // SSP Controller
1912     if (features[6] & (1 << 3)){
1913         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1914     }
1915     // eSCO
1916     if (features[3] & (1<<7)){
1917         conn->remote_supported_features[0] |= 1;
1918     }
1919     // Extended features
1920     if (features[7] & (1<<7)){
1921         conn->remote_supported_features[0] |= 2;
1922     }
1923 }
1924 
1925 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1926     // SSP Host
1927     if (features[0] & (1 << 0)){
1928         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1929     }
1930     // SC Host
1931     if (features[0] & (1 << 3)){
1932         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1933     }
1934 }
1935 
1936 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1937     // SC Controller
1938     if (features[1] & (1 << 0)){
1939         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1940     }
1941 }
1942 
1943 static void hci_handle_remote_features_received(hci_connection_t * conn){
1944     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1945     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1946     if (conn->bonding_flags & BONDING_DEDICATED){
1947         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1948     }
1949 }
1950 #endif
1951 
1952 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1953     // handle BT initialization
1954     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1955         hci_initializing_event_handler(packet, size);
1956     }
1957 
1958     // help with BT sleep
1959     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1960         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1961         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1962         hci_initializing_next_state();
1963     }
1964 }
1965 
1966 #ifdef ENABLE_CLASSIC
1967 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1968     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1969     conn->encryption_key_size = encryption_key_size;
1970 
1971     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1972         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1973         return;
1974     }
1975 
1976     // Request Authentication if not already done
1977     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1978     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1979 }
1980 #endif
1981 
1982 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1983     UNUSED(size);
1984 
1985     uint16_t manufacturer;
1986 #ifdef ENABLE_CLASSIC
1987     hci_con_handle_t handle;
1988     hci_connection_t * conn;
1989     uint8_t status;
1990 #endif
1991     // get num cmd packets - limit to 1 to reduce complexity
1992     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1993 
1994     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
1995     switch (opcode){
1996         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
1997             if (packet[5]) break;
1998             // terminate, name 248 chars
1999             packet[6+248] = 0;
2000             log_info("local name: %s", &packet[6]);
2001             break;
2002         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2003             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2004             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2005                 uint16_t acl_len = little_endian_read_16(packet, 6);
2006                 uint16_t sco_len = packet[8];
2007 
2008                 // determine usable ACL/SCO payload size
2009                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2010                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2011 
2012                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2013                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2014 
2015                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2016                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2017                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2018             }
2019             break;
2020         case HCI_OPCODE_HCI_READ_RSSI:
2021             if (packet[5] == ERROR_CODE_SUCCESS){
2022                 uint8_t event[5];
2023                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2024                 event[1] = 3;
2025                 (void)memcpy(&event[2], &packet[6], 3);
2026                 hci_emit_event(event, sizeof(event), 1);
2027             }
2028             break;
2029 #ifdef ENABLE_BLE
2030         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2031             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2032             hci_stack->le_acl_packets_total_num = packet[8];
2033             // determine usable ACL payload size
2034             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2035                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2036             }
2037             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2038             break;
2039 #endif
2040 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2041         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2042             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2043             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2044             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);
2045             break;
2046 #endif
2047 #ifdef ENABLE_LE_CENTRAL
2048         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2049             hci_stack->le_whitelist_capacity = packet[6];
2050             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2051             break;
2052 #endif
2053         case HCI_OPCODE_HCI_READ_BD_ADDR:
2054             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2055             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));
2056 #ifdef ENABLE_CLASSIC
2057             if (hci_stack->link_key_db){
2058                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2059             }
2060 #endif
2061             break;
2062 #ifdef ENABLE_CLASSIC
2063         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2064             hci_emit_discoverable_enabled(hci_stack->discoverable);
2065             break;
2066         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2067             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2068                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2069                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2070                 hci_emit_event(event, sizeof(event), 1);
2071             }
2072             break;
2073 #endif
2074         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2075             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2076 
2077 #ifdef ENABLE_CLASSIC
2078             // determine usable ACL packet types based on host buffer size and supported features
2079             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2080             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2081 #endif
2082             // Classic/LE
2083             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2084             break;
2085         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2086             manufacturer = little_endian_read_16(packet, 10);
2087             // map Cypress to Broadcom
2088             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2089                 log_info("Treat Cypress as Broadcom");
2090                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2091                 little_endian_store_16(packet, 10, manufacturer);
2092             }
2093             hci_stack->manufacturer = manufacturer;
2094             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2095             break;
2096         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2097             hci_stack->local_supported_commands[0] =
2098                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2099                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2100                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2101                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2102                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2103                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2104                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2105                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2106             hci_stack->local_supported_commands[1] =
2107                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2108                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2109                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u);   // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2110             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2111             break;
2112 #ifdef ENABLE_CLASSIC
2113         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2114             if (packet[5]) return;
2115             hci_stack->synchronous_flow_control_enabled = 1;
2116             break;
2117         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2118             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2119             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2120             conn   = hci_connection_for_handle(handle);
2121             if (conn != NULL) {
2122                 uint8_t key_size = 0;
2123                 if (status == 0){
2124                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2125                     log_info("Handle %04x key Size: %u", handle, key_size);
2126                 } else {
2127                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2128                 }
2129                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2130             }
2131             break;
2132 #endif
2133         default:
2134             break;
2135     }
2136 }
2137 
2138 static void event_handler(uint8_t *packet, uint16_t size){
2139 
2140     uint16_t event_length = packet[1];
2141 
2142     // assert packet is complete
2143     if (size != (event_length + 2u)){
2144         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2145         return;
2146     }
2147 
2148     bd_addr_t addr;
2149     bd_addr_type_t addr_type;
2150     hci_con_handle_t handle;
2151     hci_connection_t * conn;
2152     int i;
2153     int create_connection_cmd;
2154 
2155 #ifdef ENABLE_CLASSIC
2156     uint8_t link_type;
2157 #endif
2158 
2159     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2160 
2161     switch (hci_event_packet_get_type(packet)) {
2162 
2163         case HCI_EVENT_COMMAND_COMPLETE:
2164             handle_command_complete_event(packet, size);
2165             break;
2166 
2167         case HCI_EVENT_COMMAND_STATUS:
2168             // get num cmd packets - limit to 1 to reduce complexity
2169             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2170 
2171             // check command status to detected failed outgoing connections
2172             create_connection_cmd = 0;
2173 #ifdef ENABLE_CLASSIC
2174             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2175                 create_connection_cmd = 1;
2176             }
2177 #endif
2178 #ifdef ENABLE_LE_CENTRAL
2179             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2180                 create_connection_cmd = 1;
2181             }
2182 #endif
2183             if (create_connection_cmd) {
2184                 uint8_t status = hci_event_command_status_get_status(packet);
2185                 addr_type = hci_stack->outgoing_addr_type;
2186                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2187                 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);
2188 
2189                 // reset outgoing address info
2190                 memset(hci_stack->outgoing_addr, 0, 6);
2191                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2192 
2193                 // on error
2194                 if (status != ERROR_CODE_SUCCESS){
2195 #ifdef ENABLE_LE_CENTRAL
2196                     if (hci_is_le_connection_type(addr_type)){
2197                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2198                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2199                     }
2200 #endif
2201                     // error => outgoing connection failed
2202                     if (conn != NULL){
2203                         hci_handle_connection_failed(conn, status);
2204                     }
2205                 }
2206             }
2207             break;
2208 
2209         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2210             if (size < 3) return;
2211             uint16_t num_handles = packet[2];
2212             if (size != (3u + num_handles * 4u)) return;
2213             uint16_t offset = 3;
2214             for (i=0; i<num_handles;i++){
2215                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2216                 offset += 2u;
2217                 uint16_t num_packets = little_endian_read_16(packet, offset);
2218                 offset += 2u;
2219 
2220                 conn = hci_connection_for_handle(handle);
2221                 if (!conn){
2222                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2223                     continue;
2224                 }
2225 
2226                 if (conn->num_packets_sent >= num_packets){
2227                     conn->num_packets_sent -= num_packets;
2228                 } else {
2229                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2230                     conn->num_packets_sent = 0;
2231                 }
2232                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2233 
2234 #ifdef ENABLE_CLASSIC
2235                 // For SCO, we do the can_send_now_check here
2236                 hci_notify_if_sco_can_send_now();
2237 #endif
2238             }
2239             break;
2240         }
2241 
2242 #ifdef ENABLE_CLASSIC
2243         case HCI_EVENT_INQUIRY_COMPLETE:
2244             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2245                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2246                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2247                 hci_emit_event(event, sizeof(event), 1);
2248             }
2249             break;
2250         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2251             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2252                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2253             }
2254             break;
2255         case HCI_EVENT_CONNECTION_REQUEST:
2256             reverse_bd_addr(&packet[2], addr);
2257             if (hci_stack->gap_classic_accept_callback != NULL){
2258                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2259                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2260                     bd_addr_copy(hci_stack->decline_addr, addr);
2261                     break;
2262                 }
2263             }
2264 
2265             // TODO: eval COD 8-10
2266             link_type = packet[11];
2267             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2268             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2269             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2270             if (!conn) {
2271                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2272             }
2273             if (!conn) {
2274                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2275                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2276                 bd_addr_copy(hci_stack->decline_addr, addr);
2277                 break;
2278             }
2279             conn->role  = HCI_ROLE_SLAVE;
2280             conn->state = RECEIVED_CONNECTION_REQUEST;
2281             // store info about eSCO
2282             if (link_type == 0x02){
2283                 conn->remote_supported_features[0] |= 1;
2284             }
2285             hci_run();
2286             break;
2287 
2288         case HCI_EVENT_CONNECTION_COMPLETE:
2289             // Connection management
2290             reverse_bd_addr(&packet[5], addr);
2291             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2292             addr_type = BD_ADDR_TYPE_ACL;
2293             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2294             if (conn) {
2295                 if (!packet[2]){
2296                     conn->state = OPEN;
2297                     conn->con_handle = little_endian_read_16(packet, 3);
2298 
2299                     // queue get remote feature
2300                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2301 
2302                     // queue set supervision timeout if we're master
2303                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2304                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2305                     }
2306 
2307                     // restart timer
2308                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2309                     btstack_run_loop_add_timer(&conn->timeout);
2310 
2311                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2312 
2313                     hci_emit_nr_connections_changed();
2314                 } else {
2315                     // connection failed
2316                     hci_handle_connection_failed(conn, packet[2]);
2317                 }
2318             }
2319             break;
2320 
2321         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2322             reverse_bd_addr(&packet[5], addr);
2323             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2324             if (packet[2]){
2325                 // connection failed
2326                 break;
2327             }
2328             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2329             if (!conn) {
2330                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2331             }
2332             if (!conn) {
2333                 break;
2334             }
2335             conn->state = OPEN;
2336             conn->con_handle = little_endian_read_16(packet, 3);
2337 
2338 #ifdef ENABLE_SCO_OVER_HCI
2339             // update SCO
2340             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2341                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2342             }
2343             // trigger can send now
2344             if (hci_have_usb_transport()){
2345                 hci_stack->sco_can_send_now = 1;
2346             }
2347 #endif
2348             break;
2349 
2350         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2351             handle = little_endian_read_16(packet, 3);
2352             conn = hci_connection_for_handle(handle);
2353             if (!conn) break;
2354             if (!packet[2]){
2355                 const uint8_t * features = &packet[5];
2356                 hci_handle_remote_features_page_0(conn, features);
2357 
2358                 // read extended features if possible
2359                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2360                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2361                     break;
2362                 }
2363             }
2364             hci_handle_remote_features_received(conn);
2365             break;
2366 
2367         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2368             handle = little_endian_read_16(packet, 3);
2369             conn = hci_connection_for_handle(handle);
2370             if (!conn) break;
2371             // status = ok, page = 1
2372             if (!packet[2]) {
2373                 uint8_t page_number = packet[5];
2374                 uint8_t maximum_page_number = packet[6];
2375                 const uint8_t * features = &packet[7];
2376                 bool done = false;
2377                 switch (page_number){
2378                     case 1:
2379                         hci_handle_remote_features_page_1(conn, features);
2380                         if (maximum_page_number >= 2){
2381                             // get Secure Connections (Controller) from Page 2 if available
2382                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2383                         } else {
2384                             // otherwise, assume SC (Controller) == SC (Host)
2385                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2386                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2387                             }
2388                             done = true;
2389                         }
2390                         break;
2391                     case 2:
2392                         hci_handle_remote_features_page_2(conn, features);
2393                         done = true;
2394                         break;
2395                     default:
2396                         break;
2397                 }
2398                 if (!done) break;
2399             }
2400             hci_handle_remote_features_received(conn);
2401             break;
2402 
2403         case HCI_EVENT_LINK_KEY_REQUEST:
2404             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2405             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2406             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2407             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2408             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2409             hci_run();
2410             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2411             return;
2412 
2413         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2414             reverse_bd_addr(&packet[2], addr);
2415             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2416             if (!conn) break;
2417             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2418             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2419             // Change Connection Encryption keeps link key type
2420             if (link_key_type != CHANGED_COMBINATION_KEY){
2421                 conn->link_key_type = link_key_type;
2422             }
2423             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2424             // still forward event to allow dismiss of pairing dialog
2425             break;
2426         }
2427 
2428         case HCI_EVENT_PIN_CODE_REQUEST:
2429             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2430             // non-bondable mode: pin code negative reply will be sent
2431             if (!hci_stack->bondable){
2432                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2433                 hci_run();
2434                 return;
2435             }
2436             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2437             if (!hci_stack->link_key_db) break;
2438             hci_event_pin_code_request_get_bd_addr(packet, addr);
2439             hci_stack->link_key_db->delete_link_key(addr);
2440             break;
2441 
2442         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2443             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2444             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2445             break;
2446 
2447         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2448             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2449             if (!hci_stack->ssp_auto_accept) break;
2450             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2451             break;
2452 
2453         case HCI_EVENT_USER_PASSKEY_REQUEST:
2454             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2455             if (!hci_stack->ssp_auto_accept) break;
2456             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2457             break;
2458         case HCI_EVENT_MODE_CHANGE:
2459             handle = hci_event_mode_change_get_handle(packet);
2460             conn = hci_connection_for_handle(handle);
2461             if (!conn) break;
2462             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2463             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2464             break;
2465 #endif
2466 
2467         case HCI_EVENT_ENCRYPTION_CHANGE:
2468             handle = hci_event_encryption_change_get_connection_handle(packet);
2469             conn = hci_connection_for_handle(handle);
2470             if (!conn) break;
2471             if (hci_event_encryption_change_get_status(packet) == 0u) {
2472                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2473                 if (encryption_enabled){
2474                     if (hci_is_le_connection(conn)){
2475                         // For LE, we accept connection as encrypted
2476                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2477                     }
2478 #ifdef ENABLE_CLASSIC
2479                     else {
2480                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2481                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2482                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2483                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2484                             log_info("SC during pairing, but only E0 now -> abort");
2485                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2486                             break;
2487                         }
2488 
2489                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2490                         if (connected_uses_aes_ccm){
2491                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2492                         }
2493 
2494                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2495                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2496                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2497                         } else {
2498                             // if not, pretend everything is perfect
2499                             hci_handle_read_encryption_key_size_complete(conn, 16);
2500                         }
2501                     }
2502 #endif
2503                 } else {
2504                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2505                 }
2506             }
2507 
2508             break;
2509 
2510 #ifdef ENABLE_CLASSIC
2511         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2512             handle = hci_event_authentication_complete_get_connection_handle(packet);
2513             conn = hci_connection_for_handle(handle);
2514             if (!conn) break;
2515 
2516             // ignore authentication event if we didn't request it
2517             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2518 
2519             // dedicated bonding: send result and disconnect
2520             if (conn->bonding_flags & BONDING_DEDICATED){
2521                 conn->bonding_flags &= ~BONDING_DEDICATED;
2522                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2523                 conn->bonding_status = packet[2];
2524                 break;
2525             }
2526 
2527             // authenticated only if auth status == 0
2528             if (hci_event_authentication_complete_get_status(packet) == 0){
2529                 // authenticated
2530                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2531 
2532                 // If link key sufficient for requested security and not already encrypted, start encryption
2533                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2534                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2535                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2536                     break;
2537                 }
2538             }
2539 
2540             // emit updated security level
2541             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2542             break;
2543 #endif
2544 
2545         // HCI_EVENT_DISCONNECTION_COMPLETE
2546         // has been split, to first notify stack before shutting connection down
2547         // see end of function, too.
2548         case HCI_EVENT_DISCONNECTION_COMPLETE:
2549             if (packet[2]) break;   // status != 0
2550             handle = little_endian_read_16(packet, 3);
2551             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2552             if (hci_stack->acl_fragmentation_total_size > 0u) {
2553                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2554                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2555                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2556                     hci_stack->acl_fragmentation_total_size = 0;
2557                     hci_stack->acl_fragmentation_pos = 0;
2558                     if (release_buffer){
2559                         hci_release_packet_buffer();
2560                     }
2561                 }
2562             }
2563 
2564             conn = hci_connection_for_handle(handle);
2565             if (!conn) break;
2566             // mark connection for shutdown
2567             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2568 
2569             // emit dedicatd bonding event
2570             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2571                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2572             }
2573 
2574 #ifdef ENABLE_BLE
2575 #ifdef ENABLE_LE_PERIPHERAL
2576             // re-enable advertisements for le connections if active
2577             if (hci_is_le_connection(conn)){
2578                 hci_update_advertisements_enabled_for_current_roles();
2579             }
2580 #endif
2581 #endif
2582             break;
2583 
2584         case HCI_EVENT_HARDWARE_ERROR:
2585             log_error("Hardware Error: 0x%02x", packet[2]);
2586             if (hci_stack->hardware_error_callback){
2587                 (*hci_stack->hardware_error_callback)(packet[2]);
2588             } else {
2589                 // if no special requests, just reboot stack
2590                 hci_power_control_off();
2591                 hci_power_control_on();
2592             }
2593             break;
2594 
2595 #ifdef ENABLE_CLASSIC
2596         case HCI_EVENT_ROLE_CHANGE:
2597             if (packet[2]) break;   // status != 0
2598             reverse_bd_addr(&packet[3], addr);
2599             addr_type = BD_ADDR_TYPE_ACL;
2600             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2601             if (!conn) break;
2602             conn->role = packet[9];
2603             break;
2604 #endif
2605 
2606         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2607             // release packet buffer only for asynchronous transport and if there are not further fragements
2608             if (hci_transport_synchronous()) {
2609                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2610                 return; // instead of break: to avoid re-entering hci_run()
2611             }
2612             hci_stack->acl_fragmentation_tx_active = 0;
2613             if (hci_stack->acl_fragmentation_total_size) break;
2614             hci_release_packet_buffer();
2615 
2616             // L2CAP receives this event via the hci_emit_event below
2617 
2618 #ifdef ENABLE_CLASSIC
2619             // For SCO, we do the can_send_now_check here
2620             hci_notify_if_sco_can_send_now();
2621 #endif
2622             break;
2623 
2624 #ifdef ENABLE_CLASSIC
2625         case HCI_EVENT_SCO_CAN_SEND_NOW:
2626             // For SCO, we do the can_send_now_check here
2627             hci_stack->sco_can_send_now = 1;
2628             hci_notify_if_sco_can_send_now();
2629             return;
2630 
2631         // explode inquriy results for easier consumption
2632         case HCI_EVENT_INQUIRY_RESULT:
2633         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2634         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2635             gap_inquiry_explode(packet, size);
2636             break;
2637 #endif
2638 
2639 #ifdef ENABLE_BLE
2640         case HCI_EVENT_LE_META:
2641             switch (packet[2]){
2642 #ifdef ENABLE_LE_CENTRAL
2643                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2644                     // log_info("advertising report received");
2645                     if (!hci_stack->le_scanning_enabled) break;
2646                     le_handle_advertisement_report(packet, size);
2647                     break;
2648 #endif
2649                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2650                     // Connection management
2651                     reverse_bd_addr(&packet[8], addr);
2652                     addr_type = (bd_addr_type_t)packet[7];
2653                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2654                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2655 
2656 #ifdef ENABLE_LE_CENTRAL
2657                     // handle error: error is reported only to the initiator -> outgoing connection
2658                     if (packet[3]){
2659 
2660                         // handle cancelled outgoing connection
2661                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2662                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2663                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2664                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2665                             // whitelist connect
2666                             if (hci_is_le_connection_type(addr_type)){
2667                                 hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2668                                 hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2669                             }
2670                             // get outgoing connection conn struct for direct connect
2671                             conn = gap_get_outgoing_connection();
2672                         }
2673 
2674                         // outgoing le connection establishment is done
2675                         if (conn){
2676                             // remove entry
2677                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2678                             btstack_memory_hci_connection_free( conn );
2679                         }
2680                         break;
2681                     }
2682 #endif
2683 
2684                     // on success, both hosts receive connection complete event
2685                     if (packet[6] == HCI_ROLE_MASTER){
2686 #ifdef ENABLE_LE_CENTRAL
2687                         // if we're master on an le connection, it was an outgoing connection and we're done with it
2688                         // note: no hci_connection_t object exists yet for connect with whitelist
2689                         if (hci_is_le_connection_type(addr_type)){
2690                             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2691                             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2692                         }
2693 #endif
2694                     } else {
2695 #ifdef ENABLE_LE_PERIPHERAL
2696                         // if we're slave, it was an incoming connection, advertisements have stopped
2697                         hci_stack->le_advertisements_active = false;
2698 #endif
2699                     }
2700                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2701                     if (!conn){
2702                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2703                     }
2704                     // no memory, sorry.
2705                     if (!conn){
2706                         break;
2707                     }
2708 
2709                     conn->state = OPEN;
2710                     conn->role  = packet[6];
2711                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2712                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2713 
2714 #ifdef ENABLE_LE_PERIPHERAL
2715                     if (packet[6] == HCI_ROLE_SLAVE){
2716                         hci_update_advertisements_enabled_for_current_roles();
2717                     }
2718 #endif
2719 
2720                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2721 
2722                     // restart timer
2723                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2724                     // btstack_run_loop_add_timer(&conn->timeout);
2725 
2726                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2727 
2728                     hci_emit_nr_connections_changed();
2729                     break;
2730 
2731                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2732                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2733                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2734                     conn = hci_connection_for_handle(handle);
2735                     if (!conn) break;
2736                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2737                     break;
2738 
2739                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2740                     // connection
2741                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2742                     conn = hci_connection_for_handle(handle);
2743                     if (conn) {
2744                         // read arguments
2745                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2746                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2747                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2748                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2749 
2750                         // validate against current connection parameter range
2751                         le_connection_parameter_range_t existing_range;
2752                         gap_get_connection_parameter_range(&existing_range);
2753                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2754                         if (update_parameter){
2755                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2756                             conn->le_conn_interval_min = le_conn_interval_min;
2757                             conn->le_conn_interval_max = le_conn_interval_max;
2758                             conn->le_conn_latency = le_conn_latency;
2759                             conn->le_supervision_timeout = le_supervision_timeout;
2760                         } else {
2761                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2762                         }
2763                     }
2764                     break;
2765 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2766                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2767                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2768                     conn = hci_connection_for_handle(handle);
2769                     if (conn) {
2770                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2771                     }
2772                     break;
2773 #endif
2774                 default:
2775                     break;
2776             }
2777             break;
2778 #endif
2779         case HCI_EVENT_VENDOR_SPECIFIC:
2780             // Vendor specific commands often create vendor specific event instead of num completed packets
2781             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2782             switch (hci_stack->manufacturer){
2783                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2784                     hci_stack->num_cmd_packets = 1;
2785                     break;
2786                 default:
2787                     break;
2788             }
2789             break;
2790         default:
2791             break;
2792     }
2793 
2794     handle_event_for_current_stack_state(packet, size);
2795 
2796     // notify upper stack
2797 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2798 
2799     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2800     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2801         if (!packet[2]){
2802             handle = little_endian_read_16(packet, 3);
2803             hci_connection_t * aConn = hci_connection_for_handle(handle);
2804             if (aConn) {
2805                 // discard connection if app did not trigger a reconnect in the event handler
2806                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2807                     hci_shutdown_connection(aConn);
2808                 }
2809             }
2810         }
2811     }
2812 
2813 	// execute main loop
2814 	hci_run();
2815 }
2816 
2817 #ifdef ENABLE_CLASSIC
2818 
2819 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2820 static void sco_schedule_tx(hci_connection_t * conn);
2821 
2822 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2823     log_debug("SCO TX Timeout");
2824     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2825     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2826     if (!conn) return;
2827 
2828     // trigger send
2829     conn->sco_tx_ready = 1;
2830     // extra packet if CVSD but SCO buffer is too short
2831     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2832         conn->sco_tx_ready++;
2833     }
2834     hci_notify_if_sco_can_send_now();
2835 }
2836 
2837 
2838 #define SCO_TX_AFTER_RX_MS (6)
2839 
2840 static void sco_schedule_tx(hci_connection_t * conn){
2841 
2842     uint32_t now = btstack_run_loop_get_time_ms();
2843     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2844     int time_delta_ms = sco_tx_ms - now;
2845 
2846     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2847 
2848     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2849     btstack_run_loop_set_timer(timer, time_delta_ms);
2850     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2851     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2852     btstack_run_loop_add_timer(timer);
2853 }
2854 
2855 static void sco_handler(uint8_t * packet, uint16_t size){
2856     // lookup connection struct
2857     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2858     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2859     if (!conn) return;
2860 
2861     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2862     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2863         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2864             packet[2] = 0x3c;
2865             memmove(&packet[3], &packet[23], 63);
2866             size = 63;
2867         }
2868     }
2869 
2870     if (hci_have_usb_transport()){
2871         // Nothing to do
2872     } else {
2873         // 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);
2874         if (hci_stack->synchronous_flow_control_enabled == 0){
2875             uint32_t now = btstack_run_loop_get_time_ms();
2876 
2877             if (!conn->sco_rx_valid){
2878                 // ignore first 10 packets
2879                 conn->sco_rx_count++;
2880                 // log_debug("sco rx count %u", conn->sco_rx_count);
2881                 if (conn->sco_rx_count == 10) {
2882                     // use first timestamp as is and pretent it just started
2883                     conn->sco_rx_ms = now;
2884                     conn->sco_rx_valid = 1;
2885                     conn->sco_rx_count = 0;
2886                     sco_schedule_tx(conn);
2887                 }
2888             } else {
2889                 // track expected arrival timme
2890                 conn->sco_rx_count++;
2891                 conn->sco_rx_ms += 7;
2892                 int delta = (int32_t) (now - conn->sco_rx_ms);
2893                 if (delta > 0){
2894                     conn->sco_rx_ms++;
2895                 }
2896                 // log_debug("sco rx %u", conn->sco_rx_ms);
2897                 sco_schedule_tx(conn);
2898             }
2899         }
2900     }
2901     // deliver to app
2902     if (hci_stack->sco_packet_handler) {
2903         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2904     }
2905 
2906 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2907     conn->num_packets_completed++;
2908     hci_stack->host_completed_packets = 1;
2909     hci_run();
2910 #endif
2911 }
2912 #endif
2913 
2914 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2915     hci_dump_packet(packet_type, 1, packet, size);
2916     switch (packet_type) {
2917         case HCI_EVENT_PACKET:
2918             event_handler(packet, size);
2919             break;
2920         case HCI_ACL_DATA_PACKET:
2921             acl_handler(packet, size);
2922             break;
2923 #ifdef ENABLE_CLASSIC
2924         case HCI_SCO_DATA_PACKET:
2925             sco_handler(packet, size);
2926             break;
2927 #endif
2928         default:
2929             break;
2930     }
2931 }
2932 
2933 /**
2934  * @brief Add event packet handler.
2935  */
2936 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2937     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2938 }
2939 
2940 
2941 /** Register HCI packet handlers */
2942 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2943     hci_stack->acl_packet_handler = handler;
2944 }
2945 
2946 #ifdef ENABLE_CLASSIC
2947 /**
2948  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2949  */
2950 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2951     hci_stack->sco_packet_handler = handler;
2952 }
2953 #endif
2954 
2955 static void hci_state_reset(void){
2956     // no connections yet
2957     hci_stack->connections = NULL;
2958 
2959     // keep discoverable/connectable as this has been requested by the client(s)
2960     // hci_stack->discoverable = 0;
2961     // hci_stack->connectable = 0;
2962     // hci_stack->bondable = 1;
2963     // hci_stack->own_addr_type = 0;
2964 
2965     // buffer is free
2966     hci_stack->hci_packet_buffer_reserved = 0;
2967 
2968     // no pending cmds
2969     hci_stack->decline_reason = 0;
2970     hci_stack->new_scan_enable_value = 0xff;
2971 
2972     // LE
2973 #ifdef ENABLE_BLE
2974     memset(hci_stack->le_random_address, 0, 6);
2975     hci_stack->le_random_address_set = 0;
2976 #endif
2977 #ifdef ENABLE_LE_CENTRAL
2978     hci_stack->le_scanning_active  = 0;
2979     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2980     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2981     hci_stack->le_whitelist_capacity = 0;
2982 #endif
2983 }
2984 
2985 #ifdef ENABLE_CLASSIC
2986 /**
2987  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2988  */
2989 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2990     // store and open remote device db
2991     hci_stack->link_key_db = link_key_db;
2992     if (hci_stack->link_key_db) {
2993         hci_stack->link_key_db->open();
2994     }
2995 }
2996 #endif
2997 
2998 void hci_init(const hci_transport_t *transport, const void *config){
2999 
3000 #ifdef HAVE_MALLOC
3001     if (!hci_stack) {
3002         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3003     }
3004 #else
3005     hci_stack = &hci_stack_static;
3006 #endif
3007     memset(hci_stack, 0, sizeof(hci_stack_t));
3008 
3009     // reference to use transport layer implementation
3010     hci_stack->hci_transport = transport;
3011 
3012     // reference to used config
3013     hci_stack->config = config;
3014 
3015     // setup pointer for outgoing packet buffer
3016     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3017 
3018     // max acl payload size defined in config.h
3019     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3020 
3021     // register packet handlers with transport
3022     transport->register_packet_handler(&packet_handler);
3023 
3024     hci_stack->state = HCI_STATE_OFF;
3025 
3026     // class of device
3027     hci_stack->class_of_device = 0x007a020c; // Smartphone
3028 
3029     // bondable by default
3030     hci_stack->bondable = 1;
3031 
3032 #ifdef ENABLE_CLASSIC
3033     // classic name
3034     hci_stack->local_name = default_classic_name;
3035 
3036     // Master slave policy
3037     hci_stack->master_slave_policy = 1;
3038 
3039     // Allow Role Switch
3040     hci_stack->allow_role_switch = 1;
3041 
3042     // Default / minimum security level = 2
3043     hci_stack->gap_security_level = LEVEL_2;
3044 
3045     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3046     hci_stack->gap_required_encyrption_key_size = 7;
3047 #endif
3048 
3049     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3050     hci_stack->ssp_enable = 1;
3051     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3052     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3053     hci_stack->ssp_auto_accept = 1;
3054 
3055     // Secure Connections: enable (requires support from Controller)
3056     hci_stack->secure_connections_enable = true;
3057 
3058     // voice setting - signed 16 bit pcm data with CVSD over the air
3059     hci_stack->sco_voice_setting = 0x60;
3060 
3061 #ifdef ENABLE_LE_CENTRAL
3062     // connection parameter to use for outgoing connections
3063     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3064     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3065     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3066     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3067     hci_stack->le_connection_latency      = 4;         // 4
3068     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3069     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3070     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3071 
3072     // default LE Scanning
3073     hci_stack->le_scan_type     =   0x1; // active
3074     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3075     hci_stack->le_scan_window   =  0x30; //  30 ms
3076 #endif
3077 
3078 #ifdef ENABLE_LE_PERIPHERAL
3079     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3080 #endif
3081 
3082     // connection parameter range used to answer connection parameter update requests in l2cap
3083     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3084     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3085     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3086     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3087     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3088     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3089 
3090     hci_state_reset();
3091 }
3092 
3093 /**
3094  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3095  */
3096 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3097     hci_stack->chipset = chipset_driver;
3098 
3099     // reset chipset driver - init is also called on power_up
3100     if (hci_stack->chipset && hci_stack->chipset->init){
3101         hci_stack->chipset->init(hci_stack->config);
3102     }
3103 }
3104 
3105 /**
3106  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3107  */
3108 void hci_set_control(const btstack_control_t *hardware_control){
3109     // references to used control implementation
3110     hci_stack->control = hardware_control;
3111     // init with transport config
3112     hardware_control->init(hci_stack->config);
3113 }
3114 
3115 void hci_close(void){
3116     // close remote device db
3117     if (hci_stack->link_key_db) {
3118         hci_stack->link_key_db->close();
3119     }
3120 
3121     btstack_linked_list_iterator_t lit;
3122     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3123     while (btstack_linked_list_iterator_has_next(&lit)){
3124         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3125         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3126         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3127         hci_shutdown_connection(connection);
3128     }
3129 
3130     hci_power_control(HCI_POWER_OFF);
3131 
3132 #ifdef HAVE_MALLOC
3133     free(hci_stack);
3134 #endif
3135     hci_stack = NULL;
3136 }
3137 
3138 #ifdef ENABLE_CLASSIC
3139 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3140     // validate ranage and set
3141     if (encryption_key_size < 7)  return;
3142     if (encryption_key_size > 16) return;
3143     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3144 }
3145 
3146 void gap_set_security_level(gap_security_level_t security_level){
3147     hci_stack->gap_security_level = security_level;
3148 }
3149 
3150 gap_security_level_t gap_get_security_level(void){
3151     return hci_stack->gap_security_level;
3152 }
3153 #endif
3154 
3155 #ifdef ENABLE_CLASSIC
3156 void gap_set_class_of_device(uint32_t class_of_device){
3157     hci_stack->class_of_device = class_of_device;
3158 }
3159 
3160 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3161     hci_stack->default_link_policy_settings = default_link_policy_settings;
3162 }
3163 
3164 void gap_set_allow_role_switch(bool allow_role_switch){
3165     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3166 }
3167 
3168 uint8_t hci_get_allow_role_switch(void){
3169     return  hci_stack->allow_role_switch;
3170 }
3171 
3172 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3173     hci_stack->link_supervision_timeout = link_supervision_timeout;
3174 }
3175 
3176 void hci_disable_l2cap_timeout_check(void){
3177     disable_l2cap_timeouts = 1;
3178 }
3179 #endif
3180 
3181 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3182 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3183 void hci_set_bd_addr(bd_addr_t addr){
3184     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3185     hci_stack->custom_bd_addr_set = 1;
3186 }
3187 #endif
3188 
3189 // State-Module-Driver overview
3190 // state                    module  low-level
3191 // HCI_STATE_OFF             off      close
3192 // HCI_STATE_INITIALIZING,   on       open
3193 // HCI_STATE_WORKING,        on       open
3194 // HCI_STATE_HALTING,        on       open
3195 // HCI_STATE_SLEEPING,    off/sleep   close
3196 // HCI_STATE_FALLING_ASLEEP  on       open
3197 
3198 static int hci_power_control_on(void){
3199 
3200     // power on
3201     int err = 0;
3202     if (hci_stack->control && hci_stack->control->on){
3203         err = (*hci_stack->control->on)();
3204     }
3205     if (err){
3206         log_error( "POWER_ON failed");
3207         hci_emit_hci_open_failed();
3208         return err;
3209     }
3210 
3211     // int chipset driver
3212     if (hci_stack->chipset && hci_stack->chipset->init){
3213         hci_stack->chipset->init(hci_stack->config);
3214     }
3215 
3216     // init transport
3217     if (hci_stack->hci_transport->init){
3218         hci_stack->hci_transport->init(hci_stack->config);
3219     }
3220 
3221     // open transport
3222     err = hci_stack->hci_transport->open();
3223     if (err){
3224         log_error( "HCI_INIT failed, turning Bluetooth off again");
3225         if (hci_stack->control && hci_stack->control->off){
3226             (*hci_stack->control->off)();
3227         }
3228         hci_emit_hci_open_failed();
3229         return err;
3230     }
3231     return 0;
3232 }
3233 
3234 static void hci_power_control_off(void){
3235 
3236     log_info("hci_power_control_off");
3237 
3238     // close low-level device
3239     hci_stack->hci_transport->close();
3240 
3241     log_info("hci_power_control_off - hci_transport closed");
3242 
3243     // power off
3244     if (hci_stack->control && hci_stack->control->off){
3245         (*hci_stack->control->off)();
3246     }
3247 
3248     log_info("hci_power_control_off - control closed");
3249 
3250     hci_stack->state = HCI_STATE_OFF;
3251 }
3252 
3253 static void hci_power_control_sleep(void){
3254 
3255     log_info("hci_power_control_sleep");
3256 
3257 #if 0
3258     // don't close serial port during sleep
3259 
3260     // close low-level device
3261     hci_stack->hci_transport->close(hci_stack->config);
3262 #endif
3263 
3264     // sleep mode
3265     if (hci_stack->control && hci_stack->control->sleep){
3266         (*hci_stack->control->sleep)();
3267     }
3268 
3269     hci_stack->state = HCI_STATE_SLEEPING;
3270 }
3271 
3272 static int hci_power_control_wake(void){
3273 
3274     log_info("hci_power_control_wake");
3275 
3276     // wake on
3277     if (hci_stack->control && hci_stack->control->wake){
3278         (*hci_stack->control->wake)();
3279     }
3280 
3281 #if 0
3282     // open low-level device
3283     int err = hci_stack->hci_transport->open(hci_stack->config);
3284     if (err){
3285         log_error( "HCI_INIT failed, turning Bluetooth off again");
3286         if (hci_stack->control && hci_stack->control->off){
3287             (*hci_stack->control->off)();
3288         }
3289         hci_emit_hci_open_failed();
3290         return err;
3291     }
3292 #endif
3293 
3294     return 0;
3295 }
3296 
3297 static void hci_power_transition_to_initializing(void){
3298     // set up state machine
3299     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3300     hci_stack->hci_packet_buffer_reserved = 0;
3301     hci_stack->state = HCI_STATE_INITIALIZING;
3302     hci_stack->substate = HCI_INIT_SEND_RESET;
3303 }
3304 
3305 int hci_power_control(HCI_POWER_MODE power_mode){
3306 
3307     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3308 
3309     int err = 0;
3310     switch (hci_stack->state){
3311 
3312         case HCI_STATE_OFF:
3313             switch (power_mode){
3314                 case HCI_POWER_ON:
3315                     err = hci_power_control_on();
3316                     if (err) {
3317                         log_error("hci_power_control_on() error %d", err);
3318                         return err;
3319                     }
3320                     hci_power_transition_to_initializing();
3321                     break;
3322                 case HCI_POWER_OFF:
3323                     // do nothing
3324                     break;
3325                 case HCI_POWER_SLEEP:
3326                     // do nothing (with SLEEP == OFF)
3327                     break;
3328             }
3329             break;
3330 
3331         case HCI_STATE_INITIALIZING:
3332             switch (power_mode){
3333                 case HCI_POWER_ON:
3334                     // do nothing
3335                     break;
3336                 case HCI_POWER_OFF:
3337                     // no connections yet, just turn it off
3338                     hci_power_control_off();
3339                     break;
3340                 case HCI_POWER_SLEEP:
3341                     // no connections yet, just turn it off
3342                     hci_power_control_sleep();
3343                     break;
3344             }
3345             break;
3346 
3347         case HCI_STATE_WORKING:
3348             switch (power_mode){
3349                 case HCI_POWER_ON:
3350                     // do nothing
3351                     break;
3352                 case HCI_POWER_OFF:
3353                     // see hci_run
3354                     hci_stack->state = HCI_STATE_HALTING;
3355                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3356                     break;
3357                 case HCI_POWER_SLEEP:
3358                     // see hci_run
3359                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3360                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3361                     break;
3362             }
3363             break;
3364 
3365         case HCI_STATE_HALTING:
3366             switch (power_mode){
3367                 case HCI_POWER_ON:
3368                     hci_power_transition_to_initializing();
3369                     break;
3370                 case HCI_POWER_OFF:
3371                     // do nothing
3372                     break;
3373                 case HCI_POWER_SLEEP:
3374                     // see hci_run
3375                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3376                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3377                     break;
3378             }
3379             break;
3380 
3381         case HCI_STATE_FALLING_ASLEEP:
3382             switch (power_mode){
3383                 case HCI_POWER_ON:
3384 
3385 #ifdef HAVE_PLATFORM_IPHONE_OS
3386                     // nothing to do, if H4 supports power management
3387                     if (btstack_control_iphone_power_management_enabled()){
3388                         hci_stack->state = HCI_STATE_INITIALIZING;
3389                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3390                         break;
3391                     }
3392 #endif
3393                     hci_power_transition_to_initializing();
3394                     break;
3395                 case HCI_POWER_OFF:
3396                     // see hci_run
3397                     hci_stack->state = HCI_STATE_HALTING;
3398                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3399                     break;
3400                 case HCI_POWER_SLEEP:
3401                     // do nothing
3402                     break;
3403             }
3404             break;
3405 
3406         case HCI_STATE_SLEEPING:
3407             switch (power_mode){
3408                 case HCI_POWER_ON:
3409 
3410 #ifdef HAVE_PLATFORM_IPHONE_OS
3411                     // nothing to do, if H4 supports power management
3412                     if (btstack_control_iphone_power_management_enabled()){
3413                         hci_stack->state = HCI_STATE_INITIALIZING;
3414                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3415                         hci_update_scan_enable();
3416                         break;
3417                     }
3418 #endif
3419                     err = hci_power_control_wake();
3420                     if (err) return err;
3421                     hci_power_transition_to_initializing();
3422                     break;
3423                 case HCI_POWER_OFF:
3424                     hci_stack->state = HCI_STATE_HALTING;
3425                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3426                     break;
3427                 case HCI_POWER_SLEEP:
3428                     // do nothing
3429                     break;
3430             }
3431             break;
3432     }
3433 
3434     // create internal event
3435 	hci_emit_state();
3436 
3437 	// trigger next/first action
3438 	hci_run();
3439 
3440     return 0;
3441 }
3442 
3443 
3444 #ifdef ENABLE_CLASSIC
3445 
3446 static void hci_update_scan_enable(void){
3447     // 2 = page scan, 1 = inq scan
3448     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3449     hci_run();
3450 }
3451 
3452 void gap_discoverable_control(uint8_t enable){
3453     if (enable) enable = 1; // normalize argument
3454 
3455     if (hci_stack->discoverable == enable){
3456         hci_emit_discoverable_enabled(hci_stack->discoverable);
3457         return;
3458     }
3459 
3460     hci_stack->discoverable = enable;
3461     hci_update_scan_enable();
3462 }
3463 
3464 void gap_connectable_control(uint8_t enable){
3465     if (enable) enable = 1; // normalize argument
3466 
3467     // don't emit event
3468     if (hci_stack->connectable == enable) return;
3469 
3470     hci_stack->connectable = enable;
3471     hci_update_scan_enable();
3472 }
3473 #endif
3474 
3475 void gap_local_bd_addr(bd_addr_t address_buffer){
3476     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3477 }
3478 
3479 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3480 static void hci_host_num_completed_packets(void){
3481 
3482     // create packet manually as arrays are not supported and num_commands should not get reduced
3483     hci_reserve_packet_buffer();
3484     uint8_t * packet = hci_get_outgoing_packet_buffer();
3485 
3486     uint16_t size = 0;
3487     uint16_t num_handles = 0;
3488     packet[size++] = 0x35;
3489     packet[size++] = 0x0c;
3490     size++;  // skip param len
3491     size++;  // skip num handles
3492 
3493     // add { handle, packets } entries
3494     btstack_linked_item_t * it;
3495     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3496         hci_connection_t * connection = (hci_connection_t *) it;
3497         if (connection->num_packets_completed){
3498             little_endian_store_16(packet, size, connection->con_handle);
3499             size += 2;
3500             little_endian_store_16(packet, size, connection->num_packets_completed);
3501             size += 2;
3502             //
3503             num_handles++;
3504             connection->num_packets_completed = 0;
3505         }
3506     }
3507 
3508     packet[2] = size - 3;
3509     packet[3] = num_handles;
3510 
3511     hci_stack->host_completed_packets = 0;
3512 
3513     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3514     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3515 
3516     // release packet buffer for synchronous transport implementations
3517     if (hci_transport_synchronous()){
3518         hci_release_packet_buffer();
3519         hci_emit_transport_packet_sent();
3520     }
3521 }
3522 #endif
3523 
3524 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3525     UNUSED(ds);
3526     hci_stack->substate = HCI_HALTING_CLOSE;
3527     // allow packet handlers to defer final shutdown
3528     hci_emit_state();
3529     hci_run();
3530 }
3531 
3532 static bool hci_run_acl_fragments(void){
3533     if (hci_stack->acl_fragmentation_total_size > 0u) {
3534         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3535         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3536         if (connection) {
3537             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3538                 hci_send_acl_packet_fragments(connection);
3539                 return true;
3540             }
3541         } else {
3542             // connection gone -> discard further fragments
3543             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3544             hci_stack->acl_fragmentation_total_size = 0;
3545             hci_stack->acl_fragmentation_pos = 0;
3546         }
3547     }
3548     return false;
3549 }
3550 
3551 #ifdef ENABLE_CLASSIC
3552 static bool hci_run_general_gap_classic(void){
3553 
3554     // decline incoming connections
3555     if (hci_stack->decline_reason){
3556         uint8_t reason = hci_stack->decline_reason;
3557         hci_stack->decline_reason = 0;
3558         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3559         return true;
3560     }
3561     // send scan enable
3562     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3563         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3564         hci_stack->new_scan_enable_value = 0xff;
3565         return true;
3566     }
3567     // start/stop inquiry
3568     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3569         uint8_t duration = hci_stack->inquiry_state;
3570         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3571         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3572         return true;
3573     }
3574     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3575         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3576         hci_send_cmd(&hci_inquiry_cancel);
3577         return true;
3578     }
3579     // remote name request
3580     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3581         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3582         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3583                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3584         return true;
3585     }
3586     // pairing
3587     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3588         uint8_t state = hci_stack->gap_pairing_state;
3589         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3590         switch (state){
3591             case GAP_PAIRING_STATE_SEND_PIN:
3592                 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);
3593                 break;
3594             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3595                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3596                 break;
3597             case GAP_PAIRING_STATE_SEND_PASSKEY:
3598                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3599                 break;
3600             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3601                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3602                 break;
3603             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3604                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3605                 break;
3606             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3607                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3608                 break;
3609             default:
3610                 break;
3611         }
3612         return true;
3613     }
3614     return false;
3615 }
3616 #endif
3617 
3618 #ifdef ENABLE_BLE
3619 static bool hci_run_general_gap_le(void){
3620 
3621     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3622 
3623     if (hci_stack->state != HCI_STATE_WORKING) return false;
3624     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3625 
3626 
3627     // Phase 1: collect what to stop
3628 
3629     bool scanning_stop = false;
3630     bool connecting_stop = false;
3631     bool advertising_stop = false;
3632 
3633 #ifndef ENABLE_LE_CENTRAL
3634     UNUSED(scanning_stop);
3635     UNUSED(connecting_stop)
3636 #endif
3637 #ifndef ENABLE_LE_PERIPHERAL
3638     UNUSED(advertising_stop);
3639 #endif
3640 
3641     // check if whitelist needs modification
3642     bool whitelist_modification_pending = false;
3643     btstack_linked_list_iterator_t lit;
3644     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3645     while (btstack_linked_list_iterator_has_next(&lit)){
3646         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3647         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3648             whitelist_modification_pending = true;
3649             break;
3650         }
3651     }
3652     // check if resolving list needs modification
3653     bool resolving_list_modification_pending = false;
3654 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3655     if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
3656         resolving_list_modification_pending = true;
3657     }
3658 #endif
3659 
3660 #ifdef ENABLE_LE_CENTRAL
3661     // scanning control
3662     if (hci_stack->le_scanning_active) {
3663         // stop if:
3664         // - parameter change required
3665         // - it's disabled
3666         // - whitelist change required but used for scanning
3667         // - resolving list modified
3668         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3669         if ((hci_stack->le_scanning_param_update) ||
3670             !hci_stack->le_scanning_enabled ||
3671             scanning_uses_whitelist ||
3672             resolving_list_modification_pending){
3673 
3674             scanning_stop = true;
3675         }
3676     }
3677 #endif
3678 
3679 #ifdef ENABLE_LE_CENTRAL
3680     // connecting control
3681     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3682         // stop connecting if:
3683         // - connecting uses white and whitelist modification pending
3684         // - if it got disabled
3685         // - resolving list modified
3686         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3687         if ((connecting_uses_whitelist && whitelist_modification_pending) ||
3688             (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
3689             resolving_list_modification_pending) {
3690 
3691             connecting_stop = true;
3692         }
3693     }
3694 #endif
3695 
3696 #ifdef ENABLE_LE_PERIPHERAL
3697     // le advertisement control
3698     if (hci_stack->le_advertisements_active){
3699         // stop if:
3700         // - parameter change required
3701         // - it's disabled
3702         // - whitelist change required but used for advertisement filter policy
3703         // - resolving list modified
3704         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3705         if ((hci_stack->le_advertisements_todo != 0) ||
3706             !hci_stack->le_advertisements_enabled_for_current_roles ||
3707             (advertising_uses_whitelist & whitelist_modification_pending) ||
3708             resolving_list_modification_pending) {
3709 
3710             advertising_stop = true;
3711         }
3712     }
3713 #endif
3714 
3715 
3716     // Phase 2: stop everything that should be off during modifications
3717 
3718 #ifdef ENABLE_LE_CENTRAL
3719     if (scanning_stop){
3720         hci_stack->le_scanning_active = false;
3721         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3722         return true;
3723     }
3724 #endif
3725 
3726 #ifdef ENABLE_LE_CENTRAL
3727     if (connecting_stop){
3728         if (hci_stack->le_connecting_state != LE_CONNECTING_CANCEL){
3729             hci_send_cmd(&hci_le_create_connection_cancel);
3730             return true;
3731         }
3732     }
3733 #endif
3734 
3735 #ifdef ENABLE_LE_PERIPHERAL
3736     if (advertising_stop){
3737         hci_stack->le_advertisements_active = false;
3738         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3739         return true;
3740     }
3741 #endif
3742 
3743     // Phase 3: modify
3744 
3745 #ifdef ENABLE_LE_CENTRAL
3746     if (hci_stack->le_scanning_param_update){
3747         hci_stack->le_scanning_param_update = false;
3748         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3749                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3750         return true;
3751     }
3752 #endif
3753 
3754 #ifdef ENABLE_LE_PERIPHERAL
3755     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3756         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3757         hci_send_cmd(&hci_le_set_advertising_parameters,
3758                      hci_stack->le_advertisements_interval_min,
3759                      hci_stack->le_advertisements_interval_max,
3760                      hci_stack->le_advertisements_type,
3761                      hci_stack->le_own_addr_type,
3762                      hci_stack->le_advertisements_direct_address_type,
3763                      hci_stack->le_advertisements_direct_address,
3764                      hci_stack->le_advertisements_channel_map,
3765                      hci_stack->le_advertisements_filter_policy);
3766         return true;
3767     }
3768     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3769         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3770         uint8_t adv_data_clean[31];
3771         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3772         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3773                      hci_stack->le_advertisements_data_len);
3774         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3775         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3776         return true;
3777     }
3778     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3779         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3780         uint8_t scan_data_clean[31];
3781         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3782         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3783                      hci_stack->le_scan_response_data_len);
3784         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3785         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3786         return true;
3787     }
3788 #endif
3789 
3790 
3791 #ifdef ENABLE_LE_CENTRAL
3792     // if connect with whitelist was active and is not cancelled yet, wait until next time
3793     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
3794 #endif
3795 
3796     // LE Whitelist Management
3797     if (whitelist_modification_pending){
3798         // add/remove entries
3799         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3800         while (btstack_linked_list_iterator_has_next(&lit)){
3801             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3802 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3803 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3804 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
3805 				return true;
3806 			}
3807             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3808 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
3809                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
3810                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3811                 return true;
3812             }
3813             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
3814 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3815 				btstack_memory_whitelist_entry_free(entry);
3816             }
3817         }
3818     }
3819 
3820 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3821     // LE Resolving List Management
3822     uint16_t i;
3823     switch (hci_stack->le_resolving_list_state){
3824         case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
3825             // check if supported
3826             if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0){
3827                 log_info("LE Address Resolution not supported");
3828                 break;
3829             } else {
3830                 hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
3831                 hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
3832                 return true;
3833             }
3834             break;
3835         case LE_RESOLVING_LIST_READ_SIZE:
3836             hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
3837             hci_send_cmd(&hci_le_read_resolving_list_size);
3838             return true;
3839         case LE_RESOLVING_LIST_SEND_CLEAR:
3840             hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
3841             (void) memset(hci_stack->le_resolving_list_add_entries, 0xff, sizeof(hci_stack->le_resolving_list_add_entries));
3842 			(void) memset(hci_stack->le_resolving_list_remove_entries, 0, sizeof(hci_stack->le_resolving_list_remove_entries));
3843             hci_send_cmd(&hci_le_clear_resolving_list);
3844             return true;
3845 		case LE_RESOLVING_LIST_REMOVE_ENTRIES:
3846 			for (i = 0 ; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++){
3847 				uint8_t offset = i >> 3;
3848 				uint8_t mask = 1 << (i & 7);
3849 				if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
3850 				hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
3851 				bd_addr_t peer_identity_addreses;
3852 				int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3853 				sm_key_t peer_irk;
3854 				le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3855 				if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3856 
3857 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
3858 				// trigger whitelist entry 'update' (work around for controller bug)
3859 				btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3860 				while (btstack_linked_list_iterator_has_next(&lit)) {
3861 					whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
3862 					if (entry->address_type != peer_identity_addr_type) continue;
3863 					if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
3864 					log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
3865 					entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
3866 				}
3867 #endif
3868 
3869 				hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type, peer_identity_addreses);
3870 				return true;
3871 			}
3872 
3873 			hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
3874 
3875 			/* fall through */
3876 
3877 		case LE_RESOLVING_LIST_ADD_ENTRIES:
3878             for (i = 0 ; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++){
3879                 uint8_t offset = i >> 3;
3880                 uint8_t mask = 1 << (i & 7);
3881                 if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
3882                 hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
3883                 bd_addr_t peer_identity_addreses;
3884                 int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3885                 sm_key_t peer_irk;
3886                 le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3887                 if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3888                 const uint8_t * local_irk = gap_get_persistent_irk();
3889                 // command uses format specifier 'P' that stores 16-byte value without flip
3890                 uint8_t local_irk_flipped[16];
3891                 uint8_t peer_irk_flipped[16];
3892                 reverse_128(local_irk, local_irk_flipped);
3893                 reverse_128(peer_irk, peer_irk_flipped);
3894                 hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses, peer_irk_flipped, local_irk_flipped);
3895                 return true;
3896             }
3897 			hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3898 			break;
3899 
3900 		default:
3901             break;
3902     }
3903     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3904 #endif
3905 
3906     // Phase 4: restore state
3907 
3908 #ifdef ENABLE_LE_CENTRAL
3909     // re-start scanning
3910     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3911         hci_stack->le_scanning_active = true;
3912         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3913         return true;
3914     }
3915 #endif
3916 
3917 #ifdef ENABLE_LE_CENTRAL
3918     // re-start connecting
3919     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3920         bd_addr_t null_addr;
3921         memset(null_addr, 0, 6);
3922         hci_send_cmd(&hci_le_create_connection,
3923                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3924                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3925                      1,         // use whitelist
3926                      0,         // peer address type
3927                      null_addr, // peer bd addr
3928                      hci_stack->le_own_addr_type, // our addr type:
3929                      hci_stack->le_connection_interval_min,    // conn interval min
3930                      hci_stack->le_connection_interval_max,    // conn interval max
3931                      hci_stack->le_connection_latency,         // conn latency
3932                      hci_stack->le_supervision_timeout,        // conn latency
3933                      hci_stack->le_minimum_ce_length,          // min ce length
3934                      hci_stack->le_maximum_ce_length           // max ce length
3935         );
3936         return true;
3937     }
3938 #endif
3939 
3940 #ifdef ENABLE_LE_PERIPHERAL
3941     // re-start advertising
3942     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
3943         // check if advertisements should be enabled given
3944         hci_stack->le_advertisements_active = true;
3945         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3946         return true;
3947     }
3948 #endif
3949 
3950     return false;
3951 }
3952 #endif
3953 
3954 static bool hci_run_general_pending_commands(void){
3955     btstack_linked_item_t * it;
3956     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3957         hci_connection_t * connection = (hci_connection_t *) it;
3958 
3959         switch(connection->state){
3960             case SEND_CREATE_CONNECTION:
3961                 switch(connection->address_type){
3962 #ifdef ENABLE_CLASSIC
3963                     case BD_ADDR_TYPE_ACL:
3964                         log_info("sending hci_create_connection");
3965                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3966                         break;
3967 #endif
3968                     default:
3969 #ifdef ENABLE_BLE
3970 #ifdef ENABLE_LE_CENTRAL
3971                         log_info("sending hci_le_create_connection");
3972                         hci_send_cmd(&hci_le_create_connection,
3973                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3974                                      hci_stack->le_connection_scan_window,      // conn scan windows
3975                                      0,         // don't use whitelist
3976                                      connection->address_type, // peer address type
3977                                      connection->address,      // peer bd addr
3978                                      hci_stack->le_own_addr_type, // our addr type:
3979                                      hci_stack->le_connection_interval_min,    // conn interval min
3980                                      hci_stack->le_connection_interval_max,    // conn interval max
3981                                      hci_stack->le_connection_latency,         // conn latency
3982                                      hci_stack->le_supervision_timeout,        // conn latency
3983                                      hci_stack->le_minimum_ce_length,          // min ce length
3984                                      hci_stack->le_maximum_ce_length          // max ce length
3985                         );
3986                         connection->state = SENT_CREATE_CONNECTION;
3987 #endif
3988 #endif
3989                         break;
3990                 }
3991                 return true;
3992 
3993 #ifdef ENABLE_CLASSIC
3994             case RECEIVED_CONNECTION_REQUEST:
3995                 connection->role  = HCI_ROLE_SLAVE;
3996                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3997                     log_info("sending hci_accept_connection_request");
3998                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3999                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4000                 }
4001                 return true;
4002 #endif
4003 
4004 #ifdef ENABLE_BLE
4005 #ifdef ENABLE_LE_CENTRAL
4006             case SEND_CANCEL_CONNECTION:
4007                 connection->state = SENT_CANCEL_CONNECTION;
4008                 hci_send_cmd(&hci_le_create_connection_cancel);
4009                 return true;
4010 #endif
4011 #endif
4012             case SEND_DISCONNECT:
4013                 connection->state = SENT_DISCONNECT;
4014                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4015                 return true;
4016 
4017             default:
4018                 break;
4019         }
4020 
4021         // no further commands if connection is about to get shut down
4022         if (connection->state == SENT_DISCONNECT) continue;
4023 
4024         if (connection->authentication_flags & READ_RSSI){
4025             connectionClearAuthenticationFlags(connection, READ_RSSI);
4026             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4027             return true;
4028         }
4029 
4030 #ifdef ENABLE_CLASSIC
4031 
4032         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4033             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4034             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4035             return true;
4036         }
4037 
4038         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
4039             log_info("responding to link key request");
4040             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4041 
4042             link_key_t link_key;
4043             link_key_type_t link_key_type;
4044             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
4045 
4046             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4047             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4048             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
4049             if (sc_downgrade){
4050                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4051                 connection->state = SENT_DISCONNECT;
4052                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4053                 return true;
4054             }
4055 
4056             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
4057             if (have_link_key && security_level_sufficient){
4058                 connection->link_key_type = link_key_type;
4059                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
4060             } else {
4061                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4062             }
4063             return true;
4064         }
4065 
4066         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4067             log_info("denying to pin request");
4068             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4069             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4070             return true;
4071         }
4072 
4073         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4074             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4075             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
4076             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
4077                 // tweak authentication requirements
4078                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
4079                 if (connection->bonding_flags & BONDING_DEDICATED){
4080                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4081                 }
4082                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4083                     authreq |= 1;
4084                 }
4085                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
4086             } else {
4087                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4088             }
4089             return true;
4090         }
4091 
4092         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4093             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4094             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4095             return true;
4096         }
4097 
4098         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4099             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4100             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4101             return true;
4102         }
4103 
4104         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4105             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4106             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4107             return true;
4108         }
4109 
4110         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4111             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4112             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4113             return true;
4114         }
4115 
4116         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4117             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4118             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4119             return true;
4120         }
4121 
4122         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4123             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4124             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4125             connection->state = SENT_DISCONNECT;
4126             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4127             return true;
4128         }
4129 
4130         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4131             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4132             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4133             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4134             return true;
4135         }
4136 
4137         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4138             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4139             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4140             return true;
4141         }
4142         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4143             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4144             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4145             return true;
4146         }
4147 #endif
4148 
4149         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4150             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4151             if (connection->state != SENT_DISCONNECT){
4152                 connection->state = SENT_DISCONNECT;
4153                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4154                 return true;
4155             }
4156         }
4157 
4158 #ifdef ENABLE_CLASSIC
4159         uint16_t sniff_min_interval;
4160         switch (connection->sniff_min_interval){
4161             case 0:
4162                 break;
4163             case 0xffff:
4164                 connection->sniff_min_interval = 0;
4165                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4166                 return true;
4167             default:
4168                 sniff_min_interval = connection->sniff_min_interval;
4169                 connection->sniff_min_interval = 0;
4170                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4171                 return true;
4172         }
4173 
4174         if (connection->request_role != HCI_ROLE_INVALID){
4175             hci_role_t  role = connection->request_role;
4176             connection->request_role = HCI_ROLE_INVALID;
4177             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4178             return true;
4179         }
4180 #endif
4181 
4182 #ifdef ENABLE_BLE
4183         switch (connection->le_con_parameter_update_state){
4184             // response to L2CAP CON PARAMETER UPDATE REQUEST
4185             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4186                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4187                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4188                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4189                              0x0000, 0xffff);
4190                 return true;
4191             case CON_PARAMETER_UPDATE_REPLY:
4192                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4193                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4194                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4195                              0x0000, 0xffff);
4196                 return true;
4197             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4198                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4199                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4200                 return true;
4201             default:
4202                 break;
4203         }
4204         if (connection->le_phy_update_all_phys != 0xffu){
4205             uint8_t all_phys = connection->le_phy_update_all_phys;
4206             connection->le_phy_update_all_phys = 0xff;
4207             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);
4208             return true;
4209         }
4210 #endif
4211     }
4212     return false;
4213 }
4214 
4215 static void hci_run(void){
4216 
4217     bool done;
4218 
4219     // send continuation fragments first, as they block the prepared packet buffer
4220     done = hci_run_acl_fragments();
4221     if (done) return;
4222 
4223 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4224     // send host num completed packets next as they don't require num_cmd_packets > 0
4225     if (!hci_can_send_comand_packet_transport()) return;
4226     if (hci_stack->host_completed_packets){
4227         hci_host_num_completed_packets();
4228         return;
4229     }
4230 #endif
4231 
4232     if (!hci_can_send_command_packet_now()) return;
4233 
4234     // global/non-connection oriented commands
4235 
4236 
4237 #ifdef ENABLE_CLASSIC
4238     // general gap classic
4239     done = hci_run_general_gap_classic();
4240     if (done) return;
4241 #endif
4242 
4243 #ifdef ENABLE_BLE
4244     // general gap le
4245     done = hci_run_general_gap_le();
4246     if (done) return;
4247 #endif
4248 
4249     // send pending HCI commands
4250     done = hci_run_general_pending_commands();
4251     if (done) return;
4252 
4253     // stack state sub statemachines
4254     hci_connection_t * connection;
4255     switch (hci_stack->state){
4256         case HCI_STATE_INITIALIZING:
4257             hci_initializing_run();
4258             break;
4259 
4260         case HCI_STATE_HALTING:
4261 
4262             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4263             switch (hci_stack->substate){
4264                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4265                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4266 
4267 #ifdef ENABLE_BLE
4268 #ifdef ENABLE_LE_CENTRAL
4269                     // free whitelist entries
4270                     {
4271                         btstack_linked_list_iterator_t lit;
4272                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4273                         while (btstack_linked_list_iterator_has_next(&lit)){
4274                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4275                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4276                             btstack_memory_whitelist_entry_free(entry);
4277                         }
4278                     }
4279 #endif
4280 #endif
4281                     // close all open connections
4282                     connection =  (hci_connection_t *) hci_stack->connections;
4283                     if (connection){
4284                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4285                         if (!hci_can_send_command_packet_now()) return;
4286 
4287                         // check state
4288                         if (connection->state == SENT_DISCONNECT) return;
4289                         connection->state = SENT_DISCONNECT;
4290 
4291                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4292 
4293                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4294                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4295 
4296                         // ... which would be ignored anyway as we shutdown (free) the connection now
4297                         hci_shutdown_connection(connection);
4298 
4299                         // finally, send the disconnect command
4300                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4301                         return;
4302                     }
4303 
4304                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4305                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4306                         log_info("HCI_STATE_HALTING: wait 50 ms");
4307                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4308                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4309                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4310                         btstack_run_loop_add_timer(&hci_stack->timeout);
4311                         break;
4312                     }
4313 
4314                     /* fall through */
4315 
4316                 case HCI_HALTING_CLOSE:
4317                     log_info("HCI_STATE_HALTING, calling off");
4318 
4319                     // switch mode
4320                     hci_power_control_off();
4321 
4322                     log_info("HCI_STATE_HALTING, emitting state");
4323                     hci_emit_state();
4324                     log_info("HCI_STATE_HALTING, done");
4325                     break;
4326 
4327                 case HCI_HALTING_W4_TIMER:
4328                     // keep waiting
4329 
4330                     break;
4331                 default:
4332                     break;
4333             }
4334 
4335             break;
4336 
4337         case HCI_STATE_FALLING_ASLEEP:
4338             switch(hci_stack->substate) {
4339                 case HCI_FALLING_ASLEEP_DISCONNECT:
4340                     log_info("HCI_STATE_FALLING_ASLEEP");
4341                     // close all open connections
4342                     connection =  (hci_connection_t *) hci_stack->connections;
4343 
4344 #ifdef HAVE_PLATFORM_IPHONE_OS
4345                     // don't close connections, if H4 supports power management
4346                     if (btstack_control_iphone_power_management_enabled()){
4347                         connection = NULL;
4348                     }
4349 #endif
4350                     if (connection){
4351 
4352                         // send disconnect
4353                         if (!hci_can_send_command_packet_now()) return;
4354 
4355                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4356                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4357 
4358                         // send disconnected event right away - causes higher layer connections to get closed, too.
4359                         hci_shutdown_connection(connection);
4360                         return;
4361                     }
4362 
4363                     if (hci_classic_supported()){
4364                         // disable page and inquiry scan
4365                         if (!hci_can_send_command_packet_now()) return;
4366 
4367                         log_info("HCI_STATE_HALTING, disabling inq scans");
4368                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4369 
4370                         // continue in next sub state
4371                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4372                         break;
4373                     }
4374 
4375                     /* fall through */
4376 
4377                 case HCI_FALLING_ASLEEP_COMPLETE:
4378                     log_info("HCI_STATE_HALTING, calling sleep");
4379 #ifdef HAVE_PLATFORM_IPHONE_OS
4380                     // don't actually go to sleep, if H4 supports power management
4381                     if (btstack_control_iphone_power_management_enabled()){
4382                         // SLEEP MODE reached
4383                         hci_stack->state = HCI_STATE_SLEEPING;
4384                         hci_emit_state();
4385                         break;
4386                     }
4387 #endif
4388                     // switch mode
4389                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4390                     hci_emit_state();
4391                     break;
4392 
4393                 default:
4394                     break;
4395             }
4396             break;
4397 
4398         default:
4399             break;
4400     }
4401 }
4402 
4403 int hci_send_cmd_packet(uint8_t *packet, int size){
4404     // house-keeping
4405 
4406 #ifdef ENABLE_CLASSIC
4407     bd_addr_t addr;
4408     hci_connection_t * conn;
4409 #endif
4410 #ifdef ENABLE_LE_CENTRAL
4411     uint8_t initiator_filter_policy;
4412 #endif
4413 
4414     uint16_t opcode = little_endian_read_16(packet, 0);
4415     switch (opcode) {
4416         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4417             hci_stack->loopback_mode = packet[3];
4418             break;
4419 
4420 #ifdef ENABLE_CLASSIC
4421         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4422             reverse_bd_addr(&packet[3], addr);
4423             log_info("Create_connection to %s", bd_addr_to_str(addr));
4424 
4425             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4426             if (!conn) {
4427                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4428                 if (!conn) {
4429                     // notify client that alloc failed
4430                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4431                     return -1; // packet not sent to controller
4432                 }
4433                 conn->state = SEND_CREATE_CONNECTION;
4434                 conn->role  = HCI_ROLE_MASTER;
4435             }
4436             log_info("conn state %u", conn->state);
4437             switch (conn->state) {
4438                 // if connection active exists
4439                 case OPEN:
4440                     // and OPEN, emit connection complete command
4441                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4442                     return -1; // packet not sent to controller
4443                 case RECEIVED_DISCONNECTION_COMPLETE:
4444                     // create connection triggered in disconnect complete event, let's do it now
4445                     break;
4446                 case SEND_CREATE_CONNECTION:
4447                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4448                     break;
4449                 default:
4450                     // otherwise, just ignore as it is already in the open process
4451                     return -1; // packet not sent to controller
4452             }
4453             conn->state = SENT_CREATE_CONNECTION;
4454 
4455             // track outgoing connection
4456             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4457             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4458             break;
4459         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4460             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4461             break;
4462         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4463             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4464             break;
4465         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4466             if (hci_stack->link_key_db) {
4467                 reverse_bd_addr(&packet[3], addr);
4468                 hci_stack->link_key_db->delete_link_key(addr);
4469             }
4470             break;
4471         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4472         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4473             reverse_bd_addr(&packet[3], addr);
4474             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4475             if (conn) {
4476                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4477             }
4478             break;
4479         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4480         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4481         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4482         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4483             reverse_bd_addr(&packet[3], addr);
4484             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4485             if (conn) {
4486                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4487             }
4488             break;
4489 
4490 #ifdef ENABLE_SCO_OVER_HCI
4491         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4492             // setup_synchronous_connection? Voice setting at offset 22
4493             // TODO: compare to current setting if sco connection already active
4494             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4495             break;
4496         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4497             // accept_synchronus_connection? Voice setting at offset 18
4498             // TODO: compare to current setting if sco connection already active
4499             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4500             break;
4501 #endif
4502 #endif
4503 
4504 #ifdef ENABLE_BLE
4505         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4506             hci_stack->le_random_address_set = 1;
4507             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4508             break;
4509 #ifdef ENABLE_LE_PERIPHERAL
4510         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4511             hci_stack->le_advertisements_active = packet[3] != 0;
4512             break;
4513 #endif
4514 #ifdef ENABLE_LE_CENTRAL
4515         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4516             // white list used?
4517             initiator_filter_policy = packet[7];
4518             switch (initiator_filter_policy) {
4519                 case 0:
4520                     // whitelist not used
4521                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4522                     break;
4523                 case 1:
4524                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4525                     break;
4526                 default:
4527                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4528                     break;
4529             }
4530             // track outgoing connection
4531             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4532             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4533             break;
4534         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4535             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4536             break;
4537 #endif
4538 #endif
4539         default:
4540             break;
4541     }
4542 
4543     hci_stack->num_cmd_packets--;
4544 
4545     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4546     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4547 }
4548 
4549 // disconnect because of security block
4550 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4551     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4552     if (!connection) return;
4553     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4554 }
4555 
4556 
4557 // Configure Secure Simple Pairing
4558 
4559 #ifdef ENABLE_CLASSIC
4560 
4561 // enable will enable SSP during init
4562 void gap_ssp_set_enable(int enable){
4563     hci_stack->ssp_enable = enable;
4564 }
4565 
4566 static int hci_local_ssp_activated(void){
4567     return gap_ssp_supported() && hci_stack->ssp_enable;
4568 }
4569 
4570 // if set, BTstack will respond to io capability request using authentication requirement
4571 void gap_ssp_set_io_capability(int io_capability){
4572     hci_stack->ssp_io_capability = io_capability;
4573 }
4574 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4575     hci_stack->ssp_authentication_requirement = authentication_requirement;
4576 }
4577 
4578 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4579 void gap_ssp_set_auto_accept(int auto_accept){
4580     hci_stack->ssp_auto_accept = auto_accept;
4581 }
4582 
4583 void gap_secure_connections_enable(bool enable){
4584     hci_stack->secure_connections_enable = enable;
4585 }
4586 
4587 #endif
4588 
4589 // va_list part of hci_send_cmd
4590 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4591     if (!hci_can_send_command_packet_now()){
4592         log_error("hci_send_cmd called but cannot send packet now");
4593         return 0;
4594     }
4595 
4596     // for HCI INITIALIZATION
4597     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4598     hci_stack->last_cmd_opcode = cmd->opcode;
4599 
4600     hci_reserve_packet_buffer();
4601     uint8_t * packet = hci_stack->hci_packet_buffer;
4602     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4603     int err = hci_send_cmd_packet(packet, size);
4604 
4605     // release packet buffer on error or for synchronous transport implementations
4606     if ((err < 0) || hci_transport_synchronous()){
4607         hci_release_packet_buffer();
4608         hci_emit_transport_packet_sent();
4609     }
4610 
4611     return err;
4612 }
4613 
4614 /**
4615  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4616  */
4617 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4618     va_list argptr;
4619     va_start(argptr, cmd);
4620     int res = hci_send_cmd_va_arg(cmd, argptr);
4621     va_end(argptr);
4622     return res;
4623 }
4624 
4625 // Create various non-HCI events.
4626 // TODO: generalize, use table similar to hci_create_command
4627 
4628 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4629     // dump packet
4630     if (dump) {
4631         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4632     }
4633 
4634     // dispatch to all event handlers
4635     btstack_linked_list_iterator_t it;
4636     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4637     while (btstack_linked_list_iterator_has_next(&it)){
4638         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4639         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4640     }
4641 }
4642 
4643 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4644     if (!hci_stack->acl_packet_handler) return;
4645     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4646 }
4647 
4648 #ifdef ENABLE_CLASSIC
4649 static void hci_notify_if_sco_can_send_now(void){
4650     // notify SCO sender if waiting
4651     if (!hci_stack->sco_waiting_for_can_send_now) return;
4652     if (hci_can_send_sco_packet_now()){
4653         hci_stack->sco_waiting_for_can_send_now = 0;
4654         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4655         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4656         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4657     }
4658 }
4659 
4660 // parsing end emitting has been merged to reduce code size
4661 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4662     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4663 
4664     uint8_t * eir_data;
4665     ad_context_t context;
4666     const uint8_t * name;
4667     uint8_t         name_len;
4668 
4669     if (size < 3) return;
4670 
4671     int event_type = hci_event_packet_get_type(packet);
4672     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4673     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4674 
4675     switch (event_type){
4676         case HCI_EVENT_INQUIRY_RESULT:
4677         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4678             if (size != (3 + (num_responses * 14))) return;
4679             break;
4680         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4681             if (size != 257) return;
4682             if (num_responses != 1) return;
4683             break;
4684         default:
4685             return;
4686     }
4687 
4688     // event[1] is set at the end
4689     int i;
4690     for (i=0; i<num_responses;i++){
4691         memset(event, 0, sizeof(event));
4692         event[0] = GAP_EVENT_INQUIRY_RESULT;
4693         uint8_t event_size = 18;    // if name is not set by EIR
4694 
4695         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4696         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4697         (void)memcpy(&event[9],
4698                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4699                      3); // class of device
4700         (void)memcpy(&event[12],
4701                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4702                      2); // clock offset
4703 
4704         switch (event_type){
4705             case HCI_EVENT_INQUIRY_RESULT:
4706                 // 14,15,16,17 = 0, size 18
4707                 break;
4708             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4709                 event[14] = 1;
4710                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4711                 // 16,17 = 0, size 18
4712                 break;
4713             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4714                 event[14] = 1;
4715                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4716                 // EIR packets only contain a single inquiry response
4717                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4718                 name = NULL;
4719                 // Iterate over EIR data
4720                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4721                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4722                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4723                     const uint8_t * data = ad_iterator_get_data(&context);
4724                     // Prefer Complete Local Name over Shortend Local Name
4725                     switch (data_type){
4726                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4727                             if (name) continue;
4728                             /* fall through */
4729                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4730                             name = data;
4731                             name_len = data_size;
4732                             break;
4733                         default:
4734                             break;
4735                     }
4736                 }
4737                 if (name){
4738                     event[16] = 1;
4739                     // truncate name if needed
4740                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4741                     event[17] = len;
4742                     (void)memcpy(&event[18], name, len);
4743                     event_size += len;
4744                 }
4745                 break;
4746         }
4747         event[1] = event_size - 2;
4748         hci_emit_event(event, event_size, 1);
4749     }
4750 }
4751 #endif
4752 
4753 void hci_emit_state(void){
4754     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4755     uint8_t event[3];
4756     event[0] = BTSTACK_EVENT_STATE;
4757     event[1] = sizeof(event) - 2u;
4758     event[2] = hci_stack->state;
4759     hci_emit_event(event, sizeof(event), 1);
4760 }
4761 
4762 #ifdef ENABLE_CLASSIC
4763 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4764     uint8_t event[13];
4765     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4766     event[1] = sizeof(event) - 2;
4767     event[2] = status;
4768     little_endian_store_16(event, 3, con_handle);
4769     reverse_bd_addr(address, &event[5]);
4770     event[11] = 1; // ACL connection
4771     event[12] = 0; // encryption disabled
4772     hci_emit_event(event, sizeof(event), 1);
4773 }
4774 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4775     if (disable_l2cap_timeouts) return;
4776     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4777     uint8_t event[4];
4778     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4779     event[1] = sizeof(event) - 2;
4780     little_endian_store_16(event, 2, conn->con_handle);
4781     hci_emit_event(event, sizeof(event), 1);
4782 }
4783 #endif
4784 
4785 #ifdef ENABLE_BLE
4786 #ifdef ENABLE_LE_CENTRAL
4787 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){
4788     uint8_t event[21];
4789     event[0] = HCI_EVENT_LE_META;
4790     event[1] = sizeof(event) - 2u;
4791     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4792     event[3] = status;
4793     little_endian_store_16(event, 4, con_handle);
4794     event[6] = 0; // TODO: role
4795     event[7] = address_type;
4796     reverse_bd_addr(address, &event[8]);
4797     little_endian_store_16(event, 14, 0); // interval
4798     little_endian_store_16(event, 16, 0); // latency
4799     little_endian_store_16(event, 18, 0); // supervision timeout
4800     event[20] = 0; // master clock accuracy
4801     hci_emit_event(event, sizeof(event), 1);
4802 }
4803 #endif
4804 #endif
4805 
4806 static void hci_emit_transport_packet_sent(void){
4807     // notify upper stack that it might be possible to send again
4808     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4809     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4810 }
4811 
4812 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4813     uint8_t event[6];
4814     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4815     event[1] = sizeof(event) - 2u;
4816     event[2] = 0; // status = OK
4817     little_endian_store_16(event, 3, con_handle);
4818     event[5] = reason;
4819     hci_emit_event(event, sizeof(event), 1);
4820 }
4821 
4822 static void hci_emit_nr_connections_changed(void){
4823     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4824     uint8_t event[3];
4825     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4826     event[1] = sizeof(event) - 2u;
4827     event[2] = nr_hci_connections();
4828     hci_emit_event(event, sizeof(event), 1);
4829 }
4830 
4831 static void hci_emit_hci_open_failed(void){
4832     log_info("BTSTACK_EVENT_POWERON_FAILED");
4833     uint8_t event[2];
4834     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4835     event[1] = sizeof(event) - 2u;
4836     hci_emit_event(event, sizeof(event), 1);
4837 }
4838 
4839 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4840     log_info("hci_emit_dedicated_bonding_result %u ", status);
4841     uint8_t event[9];
4842     int pos = 0;
4843     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4844     event[pos++] = sizeof(event) - 2u;
4845     event[pos++] = status;
4846     reverse_bd_addr(address, &event[pos]);
4847     hci_emit_event(event, sizeof(event), 1);
4848 }
4849 
4850 
4851 #ifdef ENABLE_CLASSIC
4852 
4853 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4854     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4855     uint8_t event[5];
4856     int pos = 0;
4857     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4858     event[pos++] = sizeof(event) - 2;
4859     little_endian_store_16(event, 2, con_handle);
4860     pos += 2;
4861     event[pos++] = level;
4862     hci_emit_event(event, sizeof(event), 1);
4863 }
4864 
4865 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4866     if (!connection) return LEVEL_0;
4867     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4868     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4869     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4870     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4871     // LEVEL 4 always requires 128 bit encrytion key size
4872     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4873         security_level = LEVEL_3;
4874     }
4875     return security_level;
4876 }
4877 
4878 static void hci_emit_discoverable_enabled(uint8_t enabled){
4879     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4880     uint8_t event[3];
4881     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4882     event[1] = sizeof(event) - 2;
4883     event[2] = enabled;
4884     hci_emit_event(event, sizeof(event), 1);
4885 }
4886 
4887 // query if remote side supports eSCO
4888 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4889     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4890     if (!connection) return 0;
4891     return (connection->remote_supported_features[0] & 1) != 0;
4892 }
4893 
4894 static bool hci_ssp_supported(hci_connection_t * connection){
4895     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4896     return (connection->bonding_flags & mask) == mask;
4897 }
4898 
4899 // query if remote side supports SSP
4900 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4901     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4902     if (!connection) return 0;
4903     return hci_ssp_supported(connection) ? 1 : 0;
4904 }
4905 
4906 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4907     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4908 }
4909 
4910 // GAP API
4911 /**
4912  * @bbrief enable/disable bonding. default is enabled
4913  * @praram enabled
4914  */
4915 void gap_set_bondable_mode(int enable){
4916     hci_stack->bondable = enable ? 1 : 0;
4917 }
4918 /**
4919  * @brief Get bondable mode.
4920  * @return 1 if bondable
4921  */
4922 int gap_get_bondable_mode(void){
4923     return hci_stack->bondable;
4924 }
4925 
4926 /**
4927  * @brief map link keys to security levels
4928  */
4929 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4930     switch (link_key_type){
4931         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4932             return LEVEL_4;
4933         case COMBINATION_KEY:
4934         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4935             return LEVEL_3;
4936         default:
4937             return LEVEL_2;
4938     }
4939 }
4940 
4941 /**
4942  * @brief map link keys to secure connection yes/no
4943  */
4944 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4945     switch (link_key_type){
4946         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4947         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4948             return 1;
4949         default:
4950             return 0;
4951     }
4952 }
4953 
4954 /**
4955  * @brief map link keys to authenticated
4956  */
4957 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4958     switch (link_key_type){
4959         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4960         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4961             return 1;
4962         default:
4963             return 0;
4964     }
4965 }
4966 
4967 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4968     log_info("gap_mitm_protection_required_for_security_level %u", level);
4969     return level > LEVEL_2;
4970 }
4971 
4972 /**
4973  * @brief get current security level
4974  */
4975 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4976     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4977     if (!connection) return LEVEL_0;
4978     return gap_security_level_for_connection(connection);
4979 }
4980 
4981 /**
4982  * @brief request connection to device to
4983  * @result GAP_AUTHENTICATION_RESULT
4984  */
4985 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4986     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4987     if (!connection){
4988         hci_emit_security_level(con_handle, LEVEL_0);
4989         return;
4990     }
4991     gap_security_level_t current_level = gap_security_level(con_handle);
4992     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4993         requested_level, connection->requested_security_level, current_level);
4994 
4995     // assumption: earlier requested security higher than current level => security request is active
4996     if (current_level < connection->requested_security_level){
4997         if (connection->requested_security_level < requested_level){
4998             // increase requested level as new level is higher
4999 
5000             // TODO: handle re-authentication when done
5001 
5002             connection->requested_security_level = requested_level;
5003         }
5004         return;
5005     }
5006 
5007     // no request active, notify if security sufficient
5008     if (requested_level <= current_level){
5009         hci_emit_security_level(con_handle, current_level);
5010         return;
5011     }
5012 
5013     // start pairing to increase security level
5014     connection->requested_security_level = requested_level;
5015 
5016 #if 0
5017     // sending encryption request without a link key results in an error.
5018     // TODO: figure out how to use it properly
5019 
5020     // would enabling ecnryption suffice (>= LEVEL_2)?
5021     if (hci_stack->link_key_db){
5022         link_key_type_t link_key_type;
5023         link_key_t      link_key;
5024         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
5025             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
5026                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
5027                 return;
5028             }
5029         }
5030     }
5031 #endif
5032 
5033     // start to authenticate connection if not already active
5034     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
5035     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5036     hci_run();
5037 }
5038 
5039 /**
5040  * @brief start dedicated bonding with device. disconnect after bonding
5041  * @param device
5042  * @param request MITM protection
5043  * @result GAP_DEDICATED_BONDING_COMPLETE
5044  */
5045 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5046 
5047     // create connection state machine
5048     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5049 
5050     if (!connection){
5051         return BTSTACK_MEMORY_ALLOC_FAILED;
5052     }
5053 
5054     // delete linkn key
5055     gap_drop_link_key_for_bd_addr(device);
5056 
5057     // configure LEVEL_2/3, dedicated bonding
5058     connection->state = SEND_CREATE_CONNECTION;
5059     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5060     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5061     connection->bonding_flags = BONDING_DEDICATED;
5062 
5063     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5064 
5065     // handle: connnection failure (connection complete != ok)
5066     // handle: authentication failure
5067     // handle: disconnect on done
5068 
5069     hci_run();
5070 
5071     return 0;
5072 }
5073 #endif
5074 
5075 void gap_set_local_name(const char * local_name){
5076     hci_stack->local_name = local_name;
5077 }
5078 
5079 
5080 #ifdef ENABLE_BLE
5081 
5082 #ifdef ENABLE_LE_CENTRAL
5083 void gap_start_scan(void){
5084     hci_stack->le_scanning_enabled = true;
5085     hci_run();
5086 }
5087 
5088 void gap_stop_scan(void){
5089     hci_stack->le_scanning_enabled = false;
5090     hci_run();
5091 }
5092 
5093 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5094     hci_stack->le_scan_type          = scan_type;
5095     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5096     hci_stack->le_scan_interval      = scan_interval;
5097     hci_stack->le_scan_window        = scan_window;
5098     hci_stack->le_scanning_param_update = true;
5099     hci_run();
5100 }
5101 
5102 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5103     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5104 }
5105 
5106 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5107     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5108     if (!conn){
5109         // disallow if le connection is already outgoing
5110         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5111             log_error("le connection already active");
5112             return ERROR_CODE_COMMAND_DISALLOWED;
5113         }
5114 
5115         log_info("gap_connect: no connection exists yet, creating context");
5116         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5117         if (!conn){
5118             // notify client that alloc failed
5119             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5120             log_info("gap_connect: failed to alloc hci_connection_t");
5121             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5122         }
5123 
5124         // set le connecting state
5125         if (hci_is_le_connection_type(addr_type)){
5126             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5127         }
5128 
5129         conn->state = SEND_CREATE_CONNECTION;
5130         log_info("gap_connect: send create connection next");
5131         hci_run();
5132         return ERROR_CODE_SUCCESS;
5133     }
5134 
5135     if (!hci_is_le_connection(conn) ||
5136         (conn->state == SEND_CREATE_CONNECTION) ||
5137         (conn->state == SENT_CREATE_CONNECTION)) {
5138         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5139         log_error("gap_connect: classic connection or connect is already being created");
5140         return GATT_CLIENT_IN_WRONG_STATE;
5141     }
5142 
5143     // check if connection was just disconnected
5144     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5145         log_info("gap_connect: send create connection (again)");
5146         conn->state = SEND_CREATE_CONNECTION;
5147         hci_run();
5148         return ERROR_CODE_SUCCESS;
5149     }
5150 
5151     log_info("gap_connect: context exists with state %u", conn->state);
5152     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5153     hci_run();
5154     return ERROR_CODE_SUCCESS;
5155 }
5156 
5157 // @assumption: only a single outgoing LE Connection exists
5158 static hci_connection_t * gap_get_outgoing_connection(void){
5159     btstack_linked_item_t *it;
5160     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5161         hci_connection_t * conn = (hci_connection_t *) it;
5162         if (!hci_is_le_connection(conn)) continue;
5163         switch (conn->state){
5164             case SEND_CREATE_CONNECTION:
5165             case SENT_CREATE_CONNECTION:
5166             case SENT_CANCEL_CONNECTION:
5167                 return conn;
5168             default:
5169                 break;
5170         };
5171     }
5172     return NULL;
5173 }
5174 
5175 uint8_t gap_connect_cancel(void){
5176     hci_connection_t * conn = gap_get_outgoing_connection();
5177     if (!conn) return 0;
5178     switch (conn->state){
5179         case SEND_CREATE_CONNECTION:
5180             // skip sending create connection and emit event instead
5181             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5182             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5183             btstack_memory_hci_connection_free( conn );
5184             break;
5185         case SENT_CREATE_CONNECTION:
5186             // request to send cancel connection
5187             conn->state = SEND_CANCEL_CONNECTION;
5188             hci_run();
5189             break;
5190         default:
5191             break;
5192     }
5193     return 0;
5194 }
5195 #endif
5196 
5197 #ifdef ENABLE_LE_CENTRAL
5198 /**
5199  * @brief Set connection parameters for outgoing connections
5200  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5201  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5202  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5203  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5204  * @param conn_latency, default: 4
5205  * @param supervision_timeout (unit: 10ms), default: 720 ms
5206  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5207  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5208  */
5209 
5210 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5211     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5212     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5213     hci_stack->le_connection_scan_interval = conn_scan_interval;
5214     hci_stack->le_connection_scan_window = conn_scan_window;
5215     hci_stack->le_connection_interval_min = conn_interval_min;
5216     hci_stack->le_connection_interval_max = conn_interval_max;
5217     hci_stack->le_connection_latency = conn_latency;
5218     hci_stack->le_supervision_timeout = supervision_timeout;
5219     hci_stack->le_minimum_ce_length = min_ce_length;
5220     hci_stack->le_maximum_ce_length = max_ce_length;
5221 }
5222 #endif
5223 
5224 /**
5225  * @brief Updates the connection parameters for a given LE connection
5226  * @param handle
5227  * @param conn_interval_min (unit: 1.25ms)
5228  * @param conn_interval_max (unit: 1.25ms)
5229  * @param conn_latency
5230  * @param supervision_timeout (unit: 10ms)
5231  * @returns 0 if ok
5232  */
5233 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5234     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5235     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5236     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5237     connection->le_conn_interval_min = conn_interval_min;
5238     connection->le_conn_interval_max = conn_interval_max;
5239     connection->le_conn_latency = conn_latency;
5240     connection->le_supervision_timeout = supervision_timeout;
5241     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5242     hci_run();
5243     return 0;
5244 }
5245 
5246 /**
5247  * @brief Request an update of the connection parameter for a given LE connection
5248  * @param handle
5249  * @param conn_interval_min (unit: 1.25ms)
5250  * @param conn_interval_max (unit: 1.25ms)
5251  * @param conn_latency
5252  * @param supervision_timeout (unit: 10ms)
5253  * @returns 0 if ok
5254  */
5255 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5256     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5257     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5258     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5259     connection->le_conn_interval_min = conn_interval_min;
5260     connection->le_conn_interval_max = conn_interval_max;
5261     connection->le_conn_latency = conn_latency;
5262     connection->le_supervision_timeout = supervision_timeout;
5263     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5264     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5265     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5266     return 0;
5267 }
5268 
5269 #ifdef ENABLE_LE_PERIPHERAL
5270 
5271 /**
5272  * @brief Set Advertisement Data
5273  * @param advertising_data_length
5274  * @param advertising_data (max 31 octets)
5275  * @note data is not copied, pointer has to stay valid
5276  */
5277 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5278     hci_stack->le_advertisements_data_len = advertising_data_length;
5279     hci_stack->le_advertisements_data = advertising_data;
5280     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5281     hci_run();
5282 }
5283 
5284 /**
5285  * @brief Set Scan Response Data
5286  * @param advertising_data_length
5287  * @param advertising_data (max 31 octets)
5288  * @note data is not copied, pointer has to stay valid
5289  */
5290 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5291     hci_stack->le_scan_response_data_len = scan_response_data_length;
5292     hci_stack->le_scan_response_data = scan_response_data;
5293     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5294     hci_run();
5295 }
5296 
5297 /**
5298  * @brief Set Advertisement Parameters
5299  * @param adv_int_min
5300  * @param adv_int_max
5301  * @param adv_type
5302  * @param direct_address_type
5303  * @param direct_address
5304  * @param channel_map
5305  * @param filter_policy
5306  *
5307  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5308  */
5309  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5310     uint8_t direct_address_typ, bd_addr_t direct_address,
5311     uint8_t channel_map, uint8_t filter_policy) {
5312 
5313     hci_stack->le_advertisements_interval_min = adv_int_min;
5314     hci_stack->le_advertisements_interval_max = adv_int_max;
5315     hci_stack->le_advertisements_type = adv_type;
5316     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5317     hci_stack->le_advertisements_channel_map = channel_map;
5318     hci_stack->le_advertisements_filter_policy = filter_policy;
5319     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5320                  6);
5321 
5322     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5323     hci_run();
5324  }
5325 
5326 /**
5327  * @brief Enable/Disable Advertisements
5328  * @param enabled
5329  */
5330 void gap_advertisements_enable(int enabled){
5331     hci_stack->le_advertisements_enabled = enabled != 0;
5332     hci_update_advertisements_enabled_for_current_roles();
5333     hci_run();
5334 }
5335 
5336 #endif
5337 
5338 void hci_le_set_own_address_type(uint8_t own_address_type){
5339     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5340     if (own_address_type == hci_stack->le_own_addr_type) return;
5341     hci_stack->le_own_addr_type = own_address_type;
5342 
5343 #ifdef ENABLE_LE_PERIPHERAL
5344     // update advertisement parameters, too
5345     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5346     hci_run();
5347 #endif
5348 #ifdef ENABLE_LE_CENTRAL
5349     // note: we don't update scan parameters or modify ongoing connection attempts
5350 #endif
5351 }
5352 
5353 #endif
5354 
5355 uint8_t gap_disconnect(hci_con_handle_t handle){
5356     hci_connection_t * conn = hci_connection_for_handle(handle);
5357     if (!conn){
5358         hci_emit_disconnection_complete(handle, 0);
5359         return 0;
5360     }
5361     // ignore if already disconnected
5362     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5363         return 0;
5364     }
5365     conn->state = SEND_DISCONNECT;
5366     hci_run();
5367     return 0;
5368 }
5369 
5370 int gap_read_rssi(hci_con_handle_t con_handle){
5371     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5372     if (hci_connection == NULL) return 0;
5373     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5374     hci_run();
5375     return 1;
5376 }
5377 
5378 /**
5379  * @brief Get connection type
5380  * @param con_handle
5381  * @result connection_type
5382  */
5383 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5384     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5385     if (!conn) return GAP_CONNECTION_INVALID;
5386     switch (conn->address_type){
5387         case BD_ADDR_TYPE_LE_PUBLIC:
5388         case BD_ADDR_TYPE_LE_RANDOM:
5389             return GAP_CONNECTION_LE;
5390         case BD_ADDR_TYPE_SCO:
5391             return GAP_CONNECTION_SCO;
5392         case BD_ADDR_TYPE_ACL:
5393             return GAP_CONNECTION_ACL;
5394         default:
5395             return GAP_CONNECTION_INVALID;
5396     }
5397 }
5398 
5399 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5400     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5401     if (!conn) return HCI_ROLE_INVALID;
5402     return (hci_role_t) conn->role;
5403 }
5404 
5405 
5406 #ifdef ENABLE_CLASSIC
5407 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5408     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5409     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5410     conn->request_role = role;
5411     hci_run();
5412     return ERROR_CODE_SUCCESS;
5413 }
5414 #endif
5415 
5416 #ifdef ENABLE_BLE
5417 
5418 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){
5419     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5420     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5421 
5422     conn->le_phy_update_all_phys    = all_phys;
5423     conn->le_phy_update_tx_phys     = tx_phys;
5424     conn->le_phy_update_rx_phys     = rx_phys;
5425     conn->le_phy_update_phy_options = phy_options;
5426 
5427     hci_run();
5428 
5429     return 0;
5430 }
5431 
5432 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5433     // check if already in list
5434     btstack_linked_list_iterator_t it;
5435     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5436     while (btstack_linked_list_iterator_has_next(&it)) {
5437         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5438         if (entry->address_type != address_type) {
5439             continue;
5440         }
5441         if (memcmp(entry->address, address, 6) != 0) {
5442             continue;
5443         }
5444         // already in there
5445         return ERROR_CODE_COMMAND_DISALLOWED;
5446     }
5447     // alloc and add to list
5448     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5449     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5450     entry->address_type = address_type;
5451     (void)memcpy(entry->address, address, 6);
5452     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5453     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5454     return ERROR_CODE_SUCCESS;
5455 }
5456 
5457 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5458     btstack_linked_list_iterator_t it;
5459     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5460     while (btstack_linked_list_iterator_has_next(&it)){
5461         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5462         if (entry->address_type != address_type) {
5463             continue;
5464         }
5465         if (memcmp(entry->address, address, 6) != 0) {
5466             continue;
5467         }
5468         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5469             // remove from controller if already present
5470             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5471         }  else {
5472             // directly remove entry from whitelist
5473             btstack_linked_list_iterator_remove(&it);
5474             btstack_memory_whitelist_entry_free(entry);
5475         }
5476         return ERROR_CODE_SUCCESS;
5477     }
5478     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5479 }
5480 
5481 static void hci_whitelist_clear(void){
5482     btstack_linked_list_iterator_t it;
5483     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5484     while (btstack_linked_list_iterator_has_next(&it)){
5485         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5486         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5487             // remove from controller if already present
5488             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5489             continue;
5490         }
5491         // directly remove entry from whitelist
5492         btstack_linked_list_iterator_remove(&it);
5493         btstack_memory_whitelist_entry_free(entry);
5494     }
5495 }
5496 
5497 /**
5498  * @brief Clear Whitelist
5499  * @returns 0 if ok
5500  */
5501 uint8_t gap_whitelist_clear(void){
5502     hci_whitelist_clear();
5503     hci_run();
5504     return ERROR_CODE_SUCCESS;
5505 }
5506 
5507 /**
5508  * @brief Add Device to Whitelist
5509  * @param address_typ
5510  * @param address
5511  * @returns 0 if ok
5512  */
5513 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5514     uint8_t status = hci_whitelist_add(address_type, address);
5515     if (status){
5516         return status;
5517     }
5518     hci_run();
5519     return ERROR_CODE_SUCCESS;
5520 }
5521 
5522 /**
5523  * @brief Remove Device from Whitelist
5524  * @param address_typ
5525  * @param address
5526  * @returns 0 if ok
5527  */
5528 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5529     uint8_t status = hci_whitelist_remove(address_type, address);
5530     if (status){
5531         return status;
5532     }
5533     hci_run();
5534     return ERROR_CODE_SUCCESS;
5535 }
5536 
5537 #ifdef ENABLE_LE_CENTRAL
5538 /**
5539  *  @brief Connect with Whitelist
5540  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5541  *  @returns - if ok
5542  */
5543 uint8_t gap_connect_with_whitelist(void){
5544     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5545         return ERROR_CODE_COMMAND_DISALLOWED;
5546     }
5547     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5548     hci_run();
5549     return ERROR_CODE_SUCCESS;
5550 }
5551 
5552 /**
5553  * @brief Auto Connection Establishment - Start Connecting to device
5554  * @param address_typ
5555  * @param address
5556  * @returns 0 if ok
5557  */
5558 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
5559     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5560         return ERROR_CODE_COMMAND_DISALLOWED;
5561     }
5562 
5563     uint8_t status = hci_whitelist_add(address_type, address);
5564     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5565         return status;
5566     }
5567 
5568     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5569 
5570     hci_run();
5571     return ERROR_CODE_SUCCESS;
5572 }
5573 
5574 /**
5575  * @brief Auto Connection Establishment - Stop Connecting to device
5576  * @param address_typ
5577  * @param address
5578  * @returns 0 if ok
5579  */
5580 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
5581     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5582         return ERROR_CODE_COMMAND_DISALLOWED;
5583     }
5584 
5585     hci_whitelist_remove(address_type, address);
5586     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5587         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5588     }
5589     hci_run();
5590     return 0;
5591 }
5592 
5593 /**
5594  * @brief Auto Connection Establishment - Stop everything
5595  * @note  Convenience function to stop all active auto connection attempts
5596  */
5597 uint8_t gap_auto_connection_stop_all(void){
5598     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5599         return ERROR_CODE_COMMAND_DISALLOWED;
5600     }
5601     hci_whitelist_clear();
5602     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5603     hci_run();
5604     return ERROR_CODE_SUCCESS;
5605 }
5606 
5607 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5608     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5609     if (!conn) return 0;
5610     return conn->le_connection_interval;
5611 }
5612 #endif
5613 #endif
5614 
5615 #ifdef ENABLE_CLASSIC
5616 /**
5617  * @brief Set Extended Inquiry Response data
5618  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5619  * @note has to be done before stack starts up
5620  */
5621 void gap_set_extended_inquiry_response(const uint8_t * data){
5622     hci_stack->eir_data = data;
5623 }
5624 
5625 /**
5626  * @brief Start GAP Classic Inquiry
5627  * @param duration in 1.28s units
5628  * @return 0 if ok
5629  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5630  */
5631 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5632     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5633     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5634     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5635         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5636     }
5637     hci_stack->inquiry_state = duration_in_1280ms_units;
5638     hci_run();
5639     return 0;
5640 }
5641 
5642 /**
5643  * @brief Stop GAP Classic Inquiry
5644  * @returns 0 if ok
5645  */
5646 int gap_inquiry_stop(void){
5647     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5648         // emit inquiry complete event, before it even started
5649         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5650         hci_emit_event(event, sizeof(event), 1);
5651         return 0;
5652     }
5653     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5654     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5655     hci_run();
5656     return 0;
5657 }
5658 
5659 
5660 /**
5661  * @brief Remote Name Request
5662  * @param addr
5663  * @param page_scan_repetition_mode
5664  * @param clock_offset only used when bit 15 is set
5665  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5666  */
5667 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5668     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5669     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5670     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5671     hci_stack->remote_name_clock_offset = clock_offset;
5672     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5673     hci_run();
5674     return 0;
5675 }
5676 
5677 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
5678     hci_stack->gap_pairing_state = state;
5679     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5680     hci_run();
5681     return 0;
5682 }
5683 
5684 /**
5685  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5686  * @param addr
5687  * @param pin_data
5688  * @param pin_len
5689  * @return 0 if ok
5690  */
5691 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5692     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5693     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5694     hci_stack->gap_pairing_pin_len = pin_len;
5695     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5696 }
5697 
5698 /**
5699  * @brief Legacy Pairing Pin Code Response
5700  * @param addr
5701  * @param pin
5702  * @return 0 if ok
5703  */
5704 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
5705     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5706 }
5707 
5708 /**
5709  * @brief Abort Legacy Pairing
5710  * @param addr
5711  * @param pin
5712  * @return 0 if ok
5713  */
5714 int gap_pin_code_negative(bd_addr_t addr){
5715     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5716     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5717 }
5718 
5719 /**
5720  * @brief SSP Passkey Response
5721  * @param addr
5722  * @param passkey
5723  * @return 0 if ok
5724  */
5725 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
5726     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5727     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5728     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5729 }
5730 
5731 /**
5732  * @brief Abort SSP Passkey Entry/Pairing
5733  * @param addr
5734  * @param pin
5735  * @return 0 if ok
5736  */
5737 int gap_ssp_passkey_negative(const bd_addr_t addr){
5738     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5739     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5740 }
5741 
5742 /**
5743  * @brief Accept SSP Numeric Comparison
5744  * @param addr
5745  * @param passkey
5746  * @return 0 if ok
5747  */
5748 int gap_ssp_confirmation_response(const bd_addr_t addr){
5749     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5750     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5751 }
5752 
5753 /**
5754  * @brief Abort SSP Numeric Comparison/Pairing
5755  * @param addr
5756  * @param pin
5757  * @return 0 if ok
5758  */
5759 int gap_ssp_confirmation_negative(const bd_addr_t addr){
5760     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5761     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5762 }
5763 
5764 /**
5765  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5766  * @param inquiry_mode see bluetooth_defines.h
5767  */
5768 void hci_set_inquiry_mode(inquiry_mode_t mode){
5769     hci_stack->inquiry_mode = mode;
5770 }
5771 
5772 /**
5773  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5774  */
5775 void hci_set_sco_voice_setting(uint16_t voice_setting){
5776     hci_stack->sco_voice_setting = voice_setting;
5777 }
5778 
5779 /**
5780  * @brief Get SCO Voice Setting
5781  * @return current voice setting
5782  */
5783 uint16_t hci_get_sco_voice_setting(void){
5784     return hci_stack->sco_voice_setting;
5785 }
5786 
5787 static int hci_have_usb_transport(void){
5788     if (!hci_stack->hci_transport) return 0;
5789     const char * transport_name = hci_stack->hci_transport->name;
5790     if (!transport_name) return 0;
5791     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5792 }
5793 
5794 /** @brief Get SCO packet length for current SCO Voice setting
5795  *  @note  Using SCO packets of the exact length is required for USB transfer
5796  *  @return Length of SCO packets in bytes (not audio frames)
5797  */
5798 int hci_get_sco_packet_length(void){
5799     int sco_packet_length = 0;
5800 
5801 #ifdef ENABLE_SCO_OVER_HCI
5802 
5803     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5804     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5805 
5806     if (hci_have_usb_transport()){
5807         // see Core Spec for H2 USB Transfer.
5808         // 3 byte SCO header + 24 bytes per connection
5809         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5810         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5811     } else {
5812         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5813         sco_packet_length = 3 + 60 * multiplier;
5814         // assert that it still fits inside an SCO buffer
5815         if (sco_packet_length > hci_stack->sco_data_packet_length){
5816             sco_packet_length = 3 + 60;
5817         }
5818     }
5819 #endif
5820     return sco_packet_length;
5821 }
5822 
5823 /**
5824 * @brief Sets the master/slave policy
5825 * @param policy (0: attempt to become master, 1: let connecting device decide)
5826 */
5827 void hci_set_master_slave_policy(uint8_t policy){
5828     hci_stack->master_slave_policy = policy;
5829 }
5830 
5831 #endif
5832 
5833 HCI_STATE hci_get_state(void){
5834     return hci_stack->state;
5835 }
5836 
5837 #ifdef ENABLE_CLASSIC
5838 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5839     hci_stack->gap_classic_accept_callback = accept_callback;
5840 }
5841 #endif
5842 
5843 /**
5844  * @brief Set callback for Bluetooth Hardware Error
5845  */
5846 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5847     hci_stack->hardware_error_callback = fn;
5848 }
5849 
5850 void hci_disconnect_all(void){
5851     btstack_linked_list_iterator_t it;
5852     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5853     while (btstack_linked_list_iterator_has_next(&it)){
5854         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5855         if (con->state == SENT_DISCONNECT) continue;
5856         con->state = SEND_DISCONNECT;
5857     }
5858     hci_run();
5859 }
5860 
5861 uint16_t hci_get_manufacturer(void){
5862     return hci_stack->manufacturer;
5863 }
5864 
5865 #ifdef ENABLE_BLE
5866 
5867 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5868     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5869     if (!hci_con) return NULL;
5870     return &hci_con->sm_connection;
5871 }
5872 
5873 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5874 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5875 
5876 int gap_encryption_key_size(hci_con_handle_t con_handle){
5877     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5878     if (hci_connection == NULL) return 0;
5879     if (hci_is_le_connection(hci_connection)){
5880         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5881         if (sm_conn->sm_connection_encrypted) {
5882             return sm_conn->sm_actual_encryption_key_size;
5883         }
5884     }
5885 #ifdef ENABLE_CLASSIC
5886     else {
5887         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5888             return hci_connection->encryption_key_size;
5889         }
5890     }
5891 #endif
5892     return 0;
5893 }
5894 
5895 int gap_authenticated(hci_con_handle_t con_handle){
5896     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5897     if (hci_connection == NULL) return 0;
5898 
5899     switch (hci_connection->address_type){
5900         case BD_ADDR_TYPE_LE_PUBLIC:
5901         case BD_ADDR_TYPE_LE_RANDOM:
5902             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5903             return hci_connection->sm_connection.sm_connection_authenticated;
5904 #ifdef ENABLE_CLASSIC
5905         case BD_ADDR_TYPE_SCO:
5906         case BD_ADDR_TYPE_ACL:
5907             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5908 #endif
5909         default:
5910             return 0;
5911     }
5912 }
5913 
5914 int gap_secure_connection(hci_con_handle_t con_handle){
5915     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5916     if (hci_connection == NULL) return 0;
5917 
5918     switch (hci_connection->address_type){
5919         case BD_ADDR_TYPE_LE_PUBLIC:
5920         case BD_ADDR_TYPE_LE_RANDOM:
5921             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5922             return hci_connection->sm_connection.sm_connection_sc;
5923 #ifdef ENABLE_CLASSIC
5924         case BD_ADDR_TYPE_SCO:
5925         case BD_ADDR_TYPE_ACL:
5926             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5927 #endif
5928         default:
5929             return 0;
5930     }
5931 }
5932 
5933 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5934     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5935     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5936     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5937     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5938     return sm_conn->sm_connection_authorization_state;
5939 }
5940 #endif
5941 
5942 #ifdef ENABLE_CLASSIC
5943 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){
5944     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5945     if (!conn) return GAP_CONNECTION_INVALID;
5946     conn->sniff_min_interval = sniff_min_interval;
5947     conn->sniff_max_interval = sniff_max_interval;
5948     conn->sniff_attempt = sniff_attempt;
5949     conn->sniff_timeout = sniff_timeout;
5950     hci_run();
5951     return 0;
5952 }
5953 
5954 /**
5955  * @brief Exit Sniff mode
5956  * @param con_handle
5957  @ @return 0 if ok
5958  */
5959 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5960     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5961     if (!conn) return GAP_CONNECTION_INVALID;
5962     conn->sniff_min_interval = 0xffff;
5963     hci_run();
5964     return 0;
5965 }
5966 #endif
5967 
5968 void hci_halting_defer(void){
5969     if (hci_stack->state != HCI_STATE_HALTING) return;
5970     switch (hci_stack->substate){
5971         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5972         case HCI_HALTING_CLOSE:
5973             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5974             break;
5975         default:
5976             break;
5977     }
5978 }
5979 
5980 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
5981 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
5982     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
5983     if (le_device_db_index >= le_device_db_max_count()) return;
5984     uint8_t offset = le_device_db_index >> 3;
5985     uint8_t mask = 1 << (le_device_db_index & 7);
5986     hci_stack->le_resolving_list_add_entries[offset] |= mask;
5987     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
5988     	// note: go back to remove entries, otherwise, a remove + add will skip the add
5989         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
5990     }
5991 }
5992 
5993 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
5994 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
5995 	if (le_device_db_index >= le_device_db_max_count()) return;
5996 	uint8_t offset = le_device_db_index >> 3;
5997 	uint8_t mask = 1 << (le_device_db_index & 7);
5998 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
5999 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6000 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6001 	}
6002 }
6003 
6004 uint8_t gap_load_resolving_list_from_le_device_db(void){
6005 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6006 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6007 	}
6008 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6009 		// restart le resolving list update
6010 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6011 	}
6012 	return ERROR_CODE_SUCCESS;
6013 }
6014 #endif
6015 
6016 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6017 void hci_setup_test_connections_fuzz(void){
6018     hci_connection_t * conn;
6019 
6020     // default address: 66:55:44:33:00:01
6021     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6022 
6023     // setup Controller info
6024     hci_stack->num_cmd_packets = 255;
6025     hci_stack->acl_packets_total_num = 255;
6026 
6027     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6028     addr[5] = 0x01;
6029     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6030     conn->con_handle = addr[5];
6031     conn->role  = HCI_ROLE_SLAVE;
6032     conn->state = RECEIVED_CONNECTION_REQUEST;
6033     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6034 
6035     // setup incoming Classic SCO connection with con handle 0x0002
6036     addr[5] = 0x02;
6037     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6038     conn->con_handle = addr[5];
6039     conn->role  = HCI_ROLE_SLAVE;
6040     conn->state = RECEIVED_CONNECTION_REQUEST;
6041     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6042 
6043     // setup ready Classic ACL connection with con handle 0x0003
6044     addr[5] = 0x03;
6045     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6046     conn->con_handle = addr[5];
6047     conn->role  = HCI_ROLE_SLAVE;
6048     conn->state = OPEN;
6049     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6050 
6051     // setup ready Classic SCO connection with con handle 0x0004
6052     addr[5] = 0x04;
6053     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6054     conn->con_handle = addr[5];
6055     conn->role  = HCI_ROLE_SLAVE;
6056     conn->state = OPEN;
6057     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6058 
6059     // setup ready LE ACL connection with con handle 0x005 and public address
6060     addr[5] = 0x05;
6061     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6062     conn->con_handle = addr[5];
6063     conn->role  = HCI_ROLE_SLAVE;
6064     conn->state = OPEN;
6065     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6066 }
6067 
6068 void hci_free_connections_fuzz(void){
6069     btstack_linked_list_iterator_t it;
6070     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6071     while (btstack_linked_list_iterator_has_next(&it)){
6072         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6073         btstack_linked_list_iterator_remove(&it);
6074         btstack_memory_hci_connection_free(con);
6075     }
6076 }
6077 void hci_simulate_working_fuzz(void){
6078     hci_init_done();
6079     hci_stack->num_cmd_packets = 255;
6080 }
6081 #endif
6082