xref: /btstack/src/hci.c (revision a8d51f092f1b660d0f6921369ad2bc3f9368296c)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->role = HCI_ROLE_INVALID;
199     conn->address_type = addr_type;
200     conn->con_handle = 0xffff;
201     conn->authentication_flags = AUTH_FLAGS_NONE;
202     conn->bonding_flags = 0;
203     conn->requested_security_level = LEVEL_0;
204 #ifdef ENABLE_CLASSIC
205     conn->request_role = HCI_ROLE_INVALID;
206     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
207     btstack_run_loop_set_timer_context(&conn->timeout, conn);
208     hci_connection_timestamp(conn);
209 #endif
210     conn->acl_recombination_length = 0;
211     conn->acl_recombination_pos = 0;
212     conn->num_packets_sent = 0;
213 
214     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
215 #ifdef ENABLE_BLE
216     conn->le_phy_update_all_phys = 0xff;
217 #endif
218 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
219     conn->le_max_tx_octets = 27;
220 #endif
221     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
222     return conn;
223 }
224 
225 
226 /**
227  * get le connection parameter range
228 *
229  * @return le connection parameter range struct
230  */
231 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
232     *range = hci_stack->le_connection_parameter_range;
233 }
234 
235 /**
236  * set le connection parameter range
237  *
238  */
239 
240 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
241     hci_stack->le_connection_parameter_range = *range;
242 }
243 
244 /**
245  * @brief Test if connection parameters are inside in existing rage
246  * @param conn_interval_min (unit: 1.25ms)
247  * @param conn_interval_max (unit: 1.25ms)
248  * @param conn_latency
249  * @param supervision_timeout (unit: 10ms)
250  * @returns 1 if included
251  */
252 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
253     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
254     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
255 
256     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
257     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
258 
259     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
260     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
261 
262     return 1;
263 }
264 
265 /**
266  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
267  * @note: default: 1
268  * @param max_peripheral_connections
269  */
270 #ifdef ENABLE_LE_PERIPHERAL
271 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
272     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
273 }
274 #endif
275 
276 /**
277  * get hci connections iterator
278  *
279  * @return hci connections iterator
280  */
281 
282 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
283     btstack_linked_list_iterator_init(it, &hci_stack->connections);
284 }
285 
286 /**
287  * get connection for a given handle
288  *
289  * @return connection OR NULL, if not found
290  */
291 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
292     btstack_linked_list_iterator_t it;
293     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
294     while (btstack_linked_list_iterator_has_next(&it)){
295         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
296         if ( item->con_handle == con_handle ) {
297             return item;
298         }
299     }
300     return NULL;
301 }
302 
303 /**
304  * get connection for given address
305  *
306  * @return connection OR NULL, if not found
307  */
308 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
309     btstack_linked_list_iterator_t it;
310     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
311     while (btstack_linked_list_iterator_has_next(&it)){
312         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
313         if (connection->address_type != addr_type)  continue;
314         if (memcmp(addr, connection->address, 6) != 0) continue;
315         return connection;
316     }
317     return NULL;
318 }
319 
320 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
321     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
322 }
323 
324 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
325     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
326 }
327 
328 #ifdef ENABLE_CLASSIC
329 
330 #ifdef ENABLE_SCO_OVER_HCI
331 static int hci_number_sco_connections(void){
332     int connections = 0;
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
338         connections++;
339     }
340     return connections;
341 }
342 #endif
343 
344 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
345     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
346 #ifdef HAVE_EMBEDDED_TICK
347     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
348         // connections might be timed out
349         hci_emit_l2cap_check_timeout(connection);
350     }
351 #else
352     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
353         // connections might be timed out
354         hci_emit_l2cap_check_timeout(connection);
355     }
356 #endif
357 }
358 
359 static void hci_connection_timestamp(hci_connection_t *connection){
360 #ifdef HAVE_EMBEDDED_TICK
361     connection->timestamp = btstack_run_loop_embedded_get_ticks();
362 #else
363     connection->timestamp = btstack_run_loop_get_time_ms();
364 #endif
365 }
366 
367 /**
368  * add authentication flags and reset timer
369  * @note: assumes classic connection
370  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
371  */
372 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
373     bd_addr_t addr;
374     reverse_bd_addr(bd_addr, addr);
375     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
376     if (conn) {
377         connectionSetAuthenticationFlags(conn, flags);
378         hci_connection_timestamp(conn);
379     }
380 }
381 
382 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
383     hci_connection_t * conn = hci_connection_for_handle(handle);
384     if (!conn) return 0;
385     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
386     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
387     return 0;
388 }
389 
390 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
391     if (!hci_stack->link_key_db) return;
392     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
393     hci_stack->link_key_db->delete_link_key(addr);
394 }
395 
396 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
397     if (!hci_stack->link_key_db) return;
398     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
399     hci_stack->link_key_db->put_link_key(addr, link_key, type);
400 }
401 
402 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
403 	if (!hci_stack->link_key_db) return false;
404 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
405 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
406 	return result;
407 }
408 
409 void gap_delete_all_link_keys(void){
410     bd_addr_t  addr;
411     link_key_t link_key;
412     link_key_type_t type;
413     btstack_link_key_iterator_t it;
414     int ok = gap_link_key_iterator_init(&it);
415     if (!ok) {
416         log_error("could not initialize iterator");
417         return;
418     }
419     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
420         gap_drop_link_key_for_bd_addr(addr);
421     }
422     gap_link_key_iterator_done(&it);
423 }
424 
425 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
426     if (!hci_stack->link_key_db) return 0;
427     if (!hci_stack->link_key_db->iterator_init) return 0;
428     return hci_stack->link_key_db->iterator_init(it);
429 }
430 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
431     if (!hci_stack->link_key_db) return 0;
432     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
433 }
434 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
435     if (!hci_stack->link_key_db) return;
436     hci_stack->link_key_db->iterator_done(it);
437 }
438 #endif
439 
440 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
441     switch (address_type){
442         case BD_ADDR_TYPE_LE_PUBLIC:
443         case BD_ADDR_TYPE_LE_RANDOM:
444         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
445         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
446             return true;
447         default:
448             return false;
449     }
450 }
451 
452 static int hci_is_le_connection(hci_connection_t * connection){
453     return hci_is_le_connection_type(connection->address_type);
454 }
455 
456 /**
457  * count connections
458  */
459 static int nr_hci_connections(void){
460     int count = 0;
461     btstack_linked_item_t *it;
462     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
463         count++;
464     }
465     return count;
466 }
467 
468 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
469 
470     unsigned int num_packets_sent_classic = 0;
471     unsigned int num_packets_sent_le = 0;
472 
473     btstack_linked_item_t *it;
474     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
475         hci_connection_t * connection = (hci_connection_t *) it;
476         if (hci_is_le_connection(connection)){
477             num_packets_sent_le += connection->num_packets_sent;
478         }
479         if (connection->address_type == BD_ADDR_TYPE_ACL){
480             num_packets_sent_classic += connection->num_packets_sent;
481         }
482     }
483     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
484     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
485     int free_slots_le = 0;
486 
487     if (free_slots_classic < 0){
488         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
489         return 0;
490     }
491 
492     if (hci_stack->le_acl_packets_total_num){
493         // if we have LE slots, they are used
494         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
495         if (free_slots_le < 0){
496             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
497             return 0;
498         }
499     } else {
500         // otherwise, classic slots are used for LE, too
501         free_slots_classic -= num_packets_sent_le;
502         if (free_slots_classic < 0){
503             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
504             return 0;
505         }
506     }
507 
508     switch (address_type){
509         case BD_ADDR_TYPE_UNKNOWN:
510             log_error("hci_number_free_acl_slots: unknown address type");
511             return 0;
512 
513         case BD_ADDR_TYPE_ACL:
514             return free_slots_classic;
515 
516         default:
517            if (hci_stack->le_acl_packets_total_num){
518                return free_slots_le;
519            }
520            return free_slots_classic;
521     }
522 }
523 
524 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
525     // get connection type
526     hci_connection_t * connection = hci_connection_for_handle(con_handle);
527     if (!connection){
528         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
529         return 0;
530     }
531     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
532 }
533 
534 #ifdef ENABLE_CLASSIC
535 static int hci_number_free_sco_slots(void){
536     unsigned int num_sco_packets_sent  = 0;
537     btstack_linked_item_t *it;
538     if (hci_stack->synchronous_flow_control_enabled){
539         // explicit flow control
540         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
541             hci_connection_t * connection = (hci_connection_t *) it;
542             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
543             num_sco_packets_sent += connection->num_packets_sent;
544         }
545         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
546             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
547             return 0;
548         }
549         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
550     } else {
551         // implicit flow control -- TODO
552         int num_ready = 0;
553         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
554             hci_connection_t * connection = (hci_connection_t *) it;
555             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
556             if (connection->sco_tx_ready == 0) continue;
557             num_ready++;
558         }
559         return num_ready;
560     }
561 }
562 #endif
563 
564 // only used to send HCI Host Number Completed Packets
565 static int hci_can_send_comand_packet_transport(void){
566     if (hci_stack->hci_packet_buffer_reserved) return 0;
567 
568     // check for async hci transport implementations
569     if (hci_stack->hci_transport->can_send_packet_now){
570         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
571             return 0;
572         }
573     }
574     return 1;
575 }
576 
577 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
578 int hci_can_send_command_packet_now(void){
579     if (hci_can_send_comand_packet_transport() == 0) return 0;
580     return hci_stack->num_cmd_packets > 0u;
581 }
582 
583 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
584     // check for async hci transport implementations
585     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
586     return hci_stack->hci_transport->can_send_packet_now(packet_type);
587 }
588 
589 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
590     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
591     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
592 }
593 
594 int hci_can_send_acl_le_packet_now(void){
595     if (hci_stack->hci_packet_buffer_reserved) return 0;
596     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
597 }
598 
599 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
600     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
601     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
602 }
603 
604 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
605     if (hci_stack->hci_packet_buffer_reserved) return 0;
606     return hci_can_send_prepared_acl_packet_now(con_handle);
607 }
608 
609 #ifdef ENABLE_CLASSIC
610 int hci_can_send_acl_classic_packet_now(void){
611     if (hci_stack->hci_packet_buffer_reserved) return 0;
612     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
613 }
614 
615 int hci_can_send_prepared_sco_packet_now(void){
616     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
617     if (hci_have_usb_transport()){
618         return hci_stack->sco_can_send_now;
619     } else {
620         return hci_number_free_sco_slots() > 0;
621     }
622 }
623 
624 int hci_can_send_sco_packet_now(void){
625     if (hci_stack->hci_packet_buffer_reserved) return 0;
626     return hci_can_send_prepared_sco_packet_now();
627 }
628 
629 void hci_request_sco_can_send_now_event(void){
630     hci_stack->sco_waiting_for_can_send_now = 1;
631     hci_notify_if_sco_can_send_now();
632 }
633 #endif
634 
635 // used for internal checks in l2cap.c
636 int hci_is_packet_buffer_reserved(void){
637     return hci_stack->hci_packet_buffer_reserved;
638 }
639 
640 // reserves outgoing packet buffer. @returns 1 if successful
641 int hci_reserve_packet_buffer(void){
642     if (hci_stack->hci_packet_buffer_reserved) {
643         log_error("hci_reserve_packet_buffer called but buffer already reserved");
644         return 0;
645     }
646     hci_stack->hci_packet_buffer_reserved = 1;
647     return 1;
648 }
649 
650 void hci_release_packet_buffer(void){
651     hci_stack->hci_packet_buffer_reserved = 0;
652 }
653 
654 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
655 static int hci_transport_synchronous(void){
656     return hci_stack->hci_transport->can_send_packet_now == NULL;
657 }
658 
659 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
660 
661     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
662 
663     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
664     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
665     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
666         max_acl_data_packet_length = hci_stack->le_data_packets_length;
667     }
668 
669 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
670     if (hci_is_le_connection(connection)){
671         max_acl_data_packet_length = connection->le_max_tx_octets;
672     }
673 #endif
674 
675     log_debug("hci_send_acl_packet_fragments entered");
676 
677     int err;
678     // multiple packets could be send on a synchronous HCI transport
679     while (true){
680 
681         log_debug("hci_send_acl_packet_fragments loop entered");
682 
683         // get current data
684         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
685         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
686         int more_fragments = 0;
687 
688         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
689         if (current_acl_data_packet_length > max_acl_data_packet_length){
690             more_fragments = 1;
691             current_acl_data_packet_length = max_acl_data_packet_length;
692         }
693 
694         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
695         if (acl_header_pos > 0u){
696             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
697             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
698             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
699         }
700 
701         // update header len
702         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
703 
704         // count packet
705         connection->num_packets_sent++;
706         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
707 
708         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
709         if (more_fragments){
710             // update start of next fragment to send
711             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
712         } else {
713             // done
714             hci_stack->acl_fragmentation_pos = 0;
715             hci_stack->acl_fragmentation_total_size = 0;
716         }
717 
718         // send packet
719         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
720         const int size = current_acl_data_packet_length + 4;
721         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
722         hci_stack->acl_fragmentation_tx_active = 1;
723         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
724 
725         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
726 
727         // done yet?
728         if (!more_fragments) break;
729 
730         // can send more?
731         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
732     }
733 
734     log_debug("hci_send_acl_packet_fragments loop over");
735 
736     // release buffer now for synchronous transport
737     if (hci_transport_synchronous()){
738         hci_stack->acl_fragmentation_tx_active = 0;
739         hci_release_packet_buffer();
740         hci_emit_transport_packet_sent();
741     }
742 
743     return err;
744 }
745 
746 // pre: caller has reserved the packet buffer
747 int hci_send_acl_packet_buffer(int size){
748 
749     // log_info("hci_send_acl_packet_buffer size %u", size);
750 
751     if (!hci_stack->hci_packet_buffer_reserved) {
752         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
753         return 0;
754     }
755 
756     uint8_t * packet = hci_stack->hci_packet_buffer;
757     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
758 
759     // check for free places on Bluetooth module
760     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
761         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
762         hci_release_packet_buffer();
763         hci_emit_transport_packet_sent();
764         return BTSTACK_ACL_BUFFERS_FULL;
765     }
766 
767     hci_connection_t *connection = hci_connection_for_handle( con_handle);
768     if (!connection) {
769         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
770         hci_release_packet_buffer();
771         hci_emit_transport_packet_sent();
772         return 0;
773     }
774 
775 #ifdef ENABLE_CLASSIC
776     hci_connection_timestamp(connection);
777 #endif
778 
779     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
780 
781     // setup data
782     hci_stack->acl_fragmentation_total_size = size;
783     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
784 
785     return hci_send_acl_packet_fragments(connection);
786 }
787 
788 #ifdef ENABLE_CLASSIC
789 // pre: caller has reserved the packet buffer
790 int hci_send_sco_packet_buffer(int size){
791 
792     // log_info("hci_send_acl_packet_buffer size %u", size);
793 
794     if (!hci_stack->hci_packet_buffer_reserved) {
795         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
796         return 0;
797     }
798 
799     uint8_t * packet = hci_stack->hci_packet_buffer;
800 
801     // skip checks in loopback mode
802     if (!hci_stack->loopback_mode){
803         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
804 
805         // check for free places on Bluetooth module
806         if (!hci_can_send_prepared_sco_packet_now()) {
807             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
808             hci_release_packet_buffer();
809             hci_emit_transport_packet_sent();
810             return BTSTACK_ACL_BUFFERS_FULL;
811         }
812 
813         // track send packet in connection struct
814         hci_connection_t *connection = hci_connection_for_handle( con_handle);
815         if (!connection) {
816             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
817             hci_release_packet_buffer();
818             hci_emit_transport_packet_sent();
819             return 0;
820         }
821 
822         if (hci_have_usb_transport()){
823             // token used
824             hci_stack->sco_can_send_now = 0;
825         } else {
826             if (hci_stack->synchronous_flow_control_enabled){
827                 connection->num_packets_sent++;
828             } else {
829                 connection->sco_tx_ready--;
830             }
831         }
832     }
833 
834     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
835     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
836 
837     if (hci_transport_synchronous()){
838         hci_release_packet_buffer();
839         hci_emit_transport_packet_sent();
840     }
841 
842     return err;
843 }
844 #endif
845 
846 static void acl_handler(uint8_t *packet, uint16_t size){
847 
848     // get info
849     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
850     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
851     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
852     uint16_t acl_length         = READ_ACL_LENGTH(packet);
853 
854     // ignore non-registered handle
855     if (!conn){
856         log_error("acl_handler called with non-registered handle %u!" , con_handle);
857         return;
858     }
859 
860     // assert packet is complete
861     if ((acl_length + 4u) != size){
862         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
863         return;
864     }
865 
866 #ifdef ENABLE_CLASSIC
867     // update idle timestamp
868     hci_connection_timestamp(conn);
869 #endif
870 
871 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
872     hci_stack->host_completed_packets = 1;
873     conn->num_packets_completed++;
874 #endif
875 
876     // handle different packet types
877     switch (acl_flags & 0x03u) {
878 
879         case 0x01: // continuation fragment
880 
881             // sanity checks
882             if (conn->acl_recombination_pos == 0u) {
883                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
884                 return;
885             }
886             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
887                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
888                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
889                 conn->acl_recombination_pos = 0;
890                 return;
891             }
892 
893             // append fragment payload (header already stored)
894             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
895                          &packet[4], acl_length);
896             conn->acl_recombination_pos += acl_length;
897 
898             // forward complete L2CAP packet if complete.
899             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
900                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
901                 // reset recombination buffer
902                 conn->acl_recombination_length = 0;
903                 conn->acl_recombination_pos = 0;
904             }
905             break;
906 
907         case 0x02: { // first fragment
908 
909             // sanity check
910             if (conn->acl_recombination_pos) {
911                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
912                 conn->acl_recombination_pos = 0;
913             }
914 
915             // peek into L2CAP packet!
916             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
917 
918             // compare fragment size to L2CAP packet size
919             if (acl_length >= (l2cap_length + 4u)){
920                 // forward fragment as L2CAP packet
921                 hci_emit_acl_packet(packet, acl_length + 4u);
922             } else {
923 
924                 if (acl_length > HCI_ACL_BUFFER_SIZE){
925                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
926                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
927                     return;
928                 }
929 
930                 // store first fragment and tweak acl length for complete package
931                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
932                              packet, acl_length + 4u);
933                 conn->acl_recombination_pos    = acl_length + 4u;
934                 conn->acl_recombination_length = l2cap_length;
935                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
936             }
937             break;
938 
939         }
940         default:
941             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
942             return;
943     }
944 
945     // execute main loop
946     hci_run();
947 }
948 
949 static void hci_shutdown_connection(hci_connection_t *conn){
950     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
951 
952 #ifdef ENABLE_CLASSIC
953 #ifdef ENABLE_SCO_OVER_HCI
954     int addr_type = conn->address_type;
955 #endif
956 #endif
957 
958     btstack_run_loop_remove_timer(&conn->timeout);
959 
960     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
961     btstack_memory_hci_connection_free( conn );
962 
963     // now it's gone
964     hci_emit_nr_connections_changed();
965 
966 #ifdef ENABLE_CLASSIC
967 #ifdef ENABLE_SCO_OVER_HCI
968     // update SCO
969     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
970         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
971     }
972 #endif
973 #endif
974 }
975 
976 #ifdef ENABLE_CLASSIC
977 
978 static const uint16_t packet_type_sizes[] = {
979     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
980     HCI_ACL_DH1_SIZE, 0, 0, 0,
981     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
982     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
983 };
984 static const uint8_t  packet_type_feature_requirement_bit[] = {
985      0, // 3 slot packets
986      1, // 5 slot packets
987     25, // EDR 2 mpbs
988     26, // EDR 3 mbps
989     39, // 3 slot EDR packts
990     40, // 5 slot EDR packet
991 };
992 static const uint16_t packet_type_feature_packet_mask[] = {
993     0x0f00, // 3 slot packets
994     0xf000, // 5 slot packets
995     0x1102, // EDR 2 mpbs
996     0x2204, // EDR 3 mbps
997     0x0300, // 3 slot EDR packts
998     0x3000, // 5 slot EDR packet
999 };
1000 
1001 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1002     // enable packet types based on size
1003     uint16_t packet_types = 0;
1004     unsigned int i;
1005     for (i=0;i<16;i++){
1006         if (packet_type_sizes[i] == 0) continue;
1007         if (packet_type_sizes[i] <= buffer_size){
1008             packet_types |= 1 << i;
1009         }
1010     }
1011     // disable packet types due to missing local supported features
1012     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1013         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1014         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1015         if (feature_set) continue;
1016         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1017         packet_types &= ~packet_type_feature_packet_mask[i];
1018     }
1019     // flip bits for "may not be used"
1020     packet_types ^= 0x3306;
1021     return packet_types;
1022 }
1023 
1024 uint16_t hci_usable_acl_packet_types(void){
1025     return hci_stack->packet_types;
1026 }
1027 #endif
1028 
1029 uint8_t* hci_get_outgoing_packet_buffer(void){
1030     // hci packet buffer is >= acl data packet length
1031     return hci_stack->hci_packet_buffer;
1032 }
1033 
1034 uint16_t hci_max_acl_data_packet_length(void){
1035     return hci_stack->acl_data_packet_length;
1036 }
1037 
1038 #ifdef ENABLE_CLASSIC
1039 int hci_extended_sco_link_supported(void){
1040     // No. 31, byte 3, bit 7
1041     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1042 }
1043 #endif
1044 
1045 int hci_non_flushable_packet_boundary_flag_supported(void){
1046     // No. 54, byte 6, bit 6
1047     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1048 }
1049 
1050 static int gap_ssp_supported(void){
1051     // No. 51, byte 6, bit 3
1052     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1053 }
1054 
1055 static int hci_classic_supported(void){
1056 #ifdef ENABLE_CLASSIC
1057     // No. 37, byte 4, bit 5, = No BR/EDR Support
1058     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1059 #else
1060     return 0;
1061 #endif
1062 }
1063 
1064 static int hci_le_supported(void){
1065 #ifdef ENABLE_BLE
1066     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1067     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1068 #else
1069     return 0;
1070 #endif
1071 }
1072 
1073 #ifdef ENABLE_BLE
1074 
1075 /**
1076  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1077  */
1078 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1079     *addr_type = hci_stack->le_own_addr_type;
1080     if (hci_stack->le_own_addr_type){
1081         (void)memcpy(addr, hci_stack->le_random_address, 6);
1082     } else {
1083         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1084     }
1085 }
1086 
1087 #ifdef ENABLE_LE_CENTRAL
1088 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1089 
1090     int offset = 3;
1091     int num_reports = packet[offset];
1092     offset += 1;
1093 
1094     int i;
1095     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1096     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1097     for (i=0; (i<num_reports) && (offset < size);i++){
1098         // sanity checks on data_length:
1099         uint8_t data_length = packet[offset + 8];
1100         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1101         if ((offset + 9u + data_length + 1u) > size)    return;
1102         // setup event
1103         uint8_t event_size = 10u + data_length;
1104         int pos = 0;
1105         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1106         event[pos++] = event_size;
1107         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1108         offset += 8;
1109         pos += 8;
1110         event[pos++] = packet[offset + 1 + data_length]; // rssi
1111         event[pos++] = data_length;
1112         offset++;
1113         (void)memcpy(&event[pos], &packet[offset], data_length);
1114         pos +=    data_length;
1115         offset += data_length + 1u; // rssi
1116         hci_emit_event(event, pos, 1);
1117     }
1118 }
1119 #endif
1120 #endif
1121 
1122 #ifdef ENABLE_BLE
1123 #ifdef ENABLE_LE_PERIPHERAL
1124 static void hci_update_advertisements_enabled_for_current_roles(void){
1125     if (hci_stack->le_advertisements_enabled){
1126         // get number of active le slave connections
1127         int num_slave_connections = 0;
1128         btstack_linked_list_iterator_t it;
1129         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1130         while (btstack_linked_list_iterator_has_next(&it)){
1131             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1132             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1133             if (con->state != OPEN) continue;
1134             if (con->role  != HCI_ROLE_SLAVE) continue;
1135             if (!hci_is_le_connection(con)) continue;
1136             num_slave_connections++;
1137         }
1138         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1139         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1140     } else {
1141         hci_stack->le_advertisements_enabled_for_current_roles = false;
1142     }
1143 }
1144 #endif
1145 #endif
1146 
1147 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1148 
1149 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1150     if (!hci_stack->config) return 0;
1151     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1152     // Limit baud rate for Broadcom chipsets to 3 mbps
1153     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1154         baud_rate = 3000000;
1155     }
1156     return baud_rate;
1157 }
1158 
1159 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1160     UNUSED(ds);
1161 
1162     switch (hci_stack->substate){
1163         case HCI_INIT_W4_SEND_RESET:
1164             log_info("Resend HCI Reset");
1165             hci_stack->substate = HCI_INIT_SEND_RESET;
1166             hci_stack->num_cmd_packets = 1;
1167             hci_run();
1168             break;
1169         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1170             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1171             if (hci_stack->hci_transport->reset_link){
1172                 hci_stack->hci_transport->reset_link();
1173             }
1174 
1175             /* fall through */
1176 
1177         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1178             log_info("Resend HCI Reset - CSR Warm Boot");
1179             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1180             hci_stack->num_cmd_packets = 1;
1181             hci_run();
1182             break;
1183         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1184             if (hci_stack->hci_transport->set_baudrate){
1185                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1186                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1187                 hci_stack->hci_transport->set_baudrate(baud_rate);
1188             }
1189             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1190             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1191                 if (hci_stack->hci_transport->reset_link){
1192                     log_info("Link Reset");
1193                     hci_stack->hci_transport->reset_link();
1194                 }
1195                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1196                 hci_run();
1197             }
1198             break;
1199         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1200             // otherwise continue
1201             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1202             hci_send_cmd(&hci_read_local_supported_commands);
1203             break;
1204         default:
1205             break;
1206     }
1207 }
1208 #endif
1209 
1210 static void hci_initializing_next_state(void){
1211     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1212 }
1213 
1214 // assumption: hci_can_send_command_packet_now() == true
1215 static void hci_initializing_run(void){
1216     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1217     switch (hci_stack->substate){
1218         case HCI_INIT_SEND_RESET:
1219             hci_state_reset();
1220 
1221 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1222             // prepare reset if command complete not received in 100ms
1223             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1224             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1225             btstack_run_loop_add_timer(&hci_stack->timeout);
1226 #endif
1227             // send command
1228             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1229             hci_send_cmd(&hci_reset);
1230             break;
1231         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1232             hci_send_cmd(&hci_read_local_version_information);
1233             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1234             break;
1235         case HCI_INIT_SEND_READ_LOCAL_NAME:
1236             hci_send_cmd(&hci_read_local_name);
1237             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1238             break;
1239 
1240 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1241         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1242             hci_state_reset();
1243             // prepare reset if command complete not received in 100ms
1244             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1245             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1246             btstack_run_loop_add_timer(&hci_stack->timeout);
1247             // send command
1248             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1249             hci_send_cmd(&hci_reset);
1250             break;
1251         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1252             hci_state_reset();
1253             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1254             hci_send_cmd(&hci_reset);
1255             break;
1256         case HCI_INIT_SEND_BAUD_CHANGE: {
1257             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1258             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1259             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1260             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1261             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1262             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1263             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1264             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1265                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1266                 btstack_run_loop_add_timer(&hci_stack->timeout);
1267             }
1268             break;
1269         }
1270         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1271             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1272             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1273             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1274             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1275             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1276             break;
1277         }
1278         case HCI_INIT_CUSTOM_INIT:
1279             // Custom initialization
1280             if (hci_stack->chipset && hci_stack->chipset->next_command){
1281                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1282                 int send_cmd = 0;
1283                 switch (hci_stack->chipset_result){
1284                     case BTSTACK_CHIPSET_VALID_COMMAND:
1285                         send_cmd = 1;
1286                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1287                         break;
1288                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1289                         send_cmd = 1;
1290                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1291                         log_info("CSR Warm Boot");
1292                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1293                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1294                         btstack_run_loop_add_timer(&hci_stack->timeout);
1295                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1296                             && hci_stack->config
1297                             && hci_stack->chipset
1298                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1299                             && hci_stack->hci_transport->set_baudrate
1300                             && hci_transport_uart_get_main_baud_rate()){
1301                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1302                         } else {
1303                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1304                         }
1305                         break;
1306                     default:
1307                         break;
1308                 }
1309 
1310                 if (send_cmd){
1311                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1312                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1313                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1314                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1315                     break;
1316                 }
1317                 log_info("Init script done");
1318 
1319                 // Init script download on Broadcom chipsets causes:
1320                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1321                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1322                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1323 
1324                     // - baud rate to reset, restore UART baud rate if needed
1325                     int need_baud_change = hci_stack->config
1326                         && hci_stack->chipset
1327                         && hci_stack->chipset->set_baudrate_command
1328                         && hci_stack->hci_transport->set_baudrate
1329                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1330                     if (need_baud_change) {
1331                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1332                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1333                         hci_stack->hci_transport->set_baudrate(baud_rate);
1334                     }
1335 
1336                     uint16_t bcm_delay_ms = 300;
1337                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1338                     //   -> Work around: wait here.
1339                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1340                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1341                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1342                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1343                     btstack_run_loop_add_timer(&hci_stack->timeout);
1344                     break;
1345                 }
1346             }
1347             // otherwise continue
1348             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1349             hci_send_cmd(&hci_read_local_supported_commands);
1350             break;
1351         case HCI_INIT_SET_BD_ADDR:
1352             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1353             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1354             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1355             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1356             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1357             break;
1358 #endif
1359 
1360         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1361             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1362             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1363             hci_send_cmd(&hci_read_local_supported_commands);
1364             break;
1365         case HCI_INIT_READ_BD_ADDR:
1366             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1367             hci_send_cmd(&hci_read_bd_addr);
1368             break;
1369         case HCI_INIT_READ_BUFFER_SIZE:
1370             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1371             hci_send_cmd(&hci_read_buffer_size);
1372             break;
1373         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1374             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1375             hci_send_cmd(&hci_read_local_supported_features);
1376             break;
1377 
1378 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1379         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1380             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1381             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1382             break;
1383         case HCI_INIT_HOST_BUFFER_SIZE:
1384             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1385             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1386                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1387             break;
1388 #endif
1389 
1390         case HCI_INIT_SET_EVENT_MASK:
1391             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1392             if (hci_le_supported()){
1393                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1394             } else {
1395                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1396                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1397             }
1398             break;
1399 
1400 #ifdef ENABLE_CLASSIC
1401         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1403             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1404             break;
1405         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1407             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1408             break;
1409         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1410             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1411             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1412             break;
1413         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1414             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1415             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1416             break;
1417         case HCI_INIT_WRITE_LOCAL_NAME: {
1418             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1419             hci_reserve_packet_buffer();
1420             uint8_t * packet = hci_stack->hci_packet_buffer;
1421             // construct HCI Command and send
1422             uint16_t opcode = hci_write_local_name.opcode;
1423             hci_stack->last_cmd_opcode = opcode;
1424             packet[0] = opcode & 0xff;
1425             packet[1] = opcode >> 8;
1426             packet[2] = DEVICE_NAME_LEN;
1427             memset(&packet[3], 0, DEVICE_NAME_LEN);
1428             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1429             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1430             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1431             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1432             // expand '00:00:00:00:00:00' in name with bd_addr
1433             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1434             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1435             break;
1436         }
1437         case HCI_INIT_WRITE_EIR_DATA: {
1438             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1439             hci_reserve_packet_buffer();
1440             uint8_t * packet = hci_stack->hci_packet_buffer;
1441             // construct HCI Command in-place and send
1442             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1443             hci_stack->last_cmd_opcode = opcode;
1444             uint16_t offset = 0;
1445             packet[offset++] = opcode & 0xff;
1446             packet[offset++] = opcode >> 8;
1447             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1448             packet[offset++] = 0;  // FEC not required
1449             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1450             if (hci_stack->eir_data){
1451                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1452                 ad_context_t context;
1453                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1454                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1455                     uint8_t size        = ad_iterator_get_data_len(&context);
1456                     const uint8_t *data = ad_iterator_get_data(&context);
1457                     // copy item
1458                     packet[offset++] = size + 1;
1459                     packet[offset++] = data_type;
1460                     memcpy(&packet[offset], data, size);
1461                     // update name item
1462                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1463                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1464                     }
1465                     offset += size;
1466                 }
1467             } else {
1468                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1469                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1470                 packet[offset++] = bytes_to_copy + 1;
1471                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1472                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1473                 // expand '00:00:00:00:00:00' in name with bd_addr
1474                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1475             }
1476             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1477             break;
1478         }
1479         case HCI_INIT_WRITE_INQUIRY_MODE:
1480             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1481             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1482             break;
1483         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1484             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1485 			hci_stack->secure_connections_active = true;
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1487             break;
1488         case HCI_INIT_WRITE_SCAN_ENABLE:
1489             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1490             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1491             break;
1492         // only sent if ENABLE_SCO_OVER_HCI is defined
1493         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1494             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1495             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1496             break;
1497         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1498             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1499             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1500             break;
1501         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1502         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1503             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1504             log_info("BCM: Route SCO data via HCI transport");
1505             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1506             break;
1507 
1508 #endif
1509 #ifdef ENABLE_BLE
1510         // LE INIT
1511         case HCI_INIT_LE_READ_BUFFER_SIZE:
1512             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1513             hci_send_cmd(&hci_le_read_buffer_size);
1514             break;
1515         case HCI_INIT_LE_SET_EVENT_MASK:
1516             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1517             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1518             break;
1519         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1520             // LE Supported Host = 1, Simultaneous Host = 0
1521             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1522             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1523             break;
1524 #endif
1525 
1526 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1527         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1528             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1529             hci_send_cmd(&hci_le_read_maximum_data_length);
1530             break;
1531         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1532             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1533             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1534             break;
1535 #endif
1536 
1537 #ifdef ENABLE_LE_CENTRAL
1538         case HCI_INIT_READ_WHITE_LIST_SIZE:
1539             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1540             hci_send_cmd(&hci_le_read_white_list_size);
1541             break;
1542         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1543             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1544             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);
1545             break;
1546 #endif
1547         default:
1548             return;
1549     }
1550 }
1551 
1552 static void hci_init_done(void){
1553     // done. tell the app
1554     log_info("hci_init_done -> HCI_STATE_WORKING");
1555     hci_stack->state = HCI_STATE_WORKING;
1556     hci_emit_state();
1557     hci_run();
1558 }
1559 
1560 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1561     bool command_completed = false;
1562     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1563         uint16_t opcode = little_endian_read_16(packet,3);
1564         if (opcode == hci_stack->last_cmd_opcode){
1565             command_completed = true;
1566             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1567         } else {
1568             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1569         }
1570     }
1571 
1572     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1573         uint8_t  status = packet[2];
1574         uint16_t opcode = little_endian_read_16(packet,4);
1575         if (opcode == hci_stack->last_cmd_opcode){
1576             if (status){
1577                 command_completed = true;
1578                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1579             } else {
1580                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1581             }
1582         } else {
1583             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1584         }
1585     }
1586 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1587     // Vendor == CSR
1588     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1589         // TODO: track actual command
1590         command_completed = true;
1591     }
1592 
1593     // Vendor == Toshiba
1594     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1595         // TODO: track actual command
1596         command_completed = true;
1597         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1598         hci_stack->num_cmd_packets = 1;
1599     }
1600 #endif
1601 
1602     return command_completed;
1603 }
1604 
1605 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1606 
1607     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1608 
1609     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1610 
1611 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1612 
1613     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1614     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1615     //
1616     // HCI Reset
1617     // Timeout 100 ms
1618     // HCI Reset
1619     // Command Complete Reset
1620     // HCI Read Local Version Information
1621     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1622     // hang...
1623     //
1624     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1625     if (!command_completed
1626             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1627             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1628 
1629         uint16_t opcode = little_endian_read_16(packet,3);
1630         if (opcode == hci_reset.opcode){
1631             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1632             return;
1633         }
1634     }
1635 
1636     // CSR & H5
1637     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1638     if (!command_completed
1639             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1640             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1641 
1642         uint16_t opcode = little_endian_read_16(packet,3);
1643         if (opcode == hci_reset.opcode){
1644             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1645             return;
1646         }
1647     }
1648 
1649     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1650     // fix: Correct substate and behave as command below
1651     if (command_completed){
1652         switch (hci_stack->substate){
1653             case HCI_INIT_SEND_RESET:
1654                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1655                 break;
1656             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1657                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1658                 break;
1659             default:
1660                 break;
1661         }
1662     }
1663 
1664 #endif
1665 
1666     if (!command_completed) return;
1667 
1668     bool need_baud_change = false;
1669     bool need_addr_change = false;
1670 
1671 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1672     need_baud_change = hci_stack->config
1673                         && hci_stack->chipset
1674                         && hci_stack->chipset->set_baudrate_command
1675                         && hci_stack->hci_transport->set_baudrate
1676                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1677 
1678     need_addr_change = hci_stack->custom_bd_addr_set
1679                         && hci_stack->chipset
1680                         && hci_stack->chipset->set_bd_addr_command;
1681 #endif
1682 
1683     switch(hci_stack->substate){
1684 
1685 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1686         case HCI_INIT_SEND_RESET:
1687             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1688             // fix: just correct substate and behave as command below
1689             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1690             btstack_run_loop_remove_timer(&hci_stack->timeout);
1691             break;
1692         case HCI_INIT_W4_SEND_RESET:
1693             btstack_run_loop_remove_timer(&hci_stack->timeout);
1694             break;
1695         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1696             log_info("Received local name, need baud change %d", (int) need_baud_change);
1697             if (need_baud_change){
1698                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1699                 return;
1700             }
1701             // skip baud change
1702             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1703             return;
1704         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1705             // for STLC2500D, baud rate change already happened.
1706             // for others, baud rate gets changed now
1707             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1708                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1709                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1710                 hci_stack->hci_transport->set_baudrate(baud_rate);
1711             }
1712             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1713             return;
1714         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1715             btstack_run_loop_remove_timer(&hci_stack->timeout);
1716             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1717             return;
1718         case HCI_INIT_W4_CUSTOM_INIT:
1719             // repeat custom init
1720             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1721             return;
1722 #else
1723         case HCI_INIT_W4_SEND_RESET:
1724             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1725             return ;
1726 #endif
1727 
1728         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1729             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1730               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1731                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1732                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1733                 return;
1734             }
1735             if (need_addr_change){
1736                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1737                 return;
1738             }
1739             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1740             return;
1741 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1742         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1743             if (need_baud_change){
1744                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1745                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1746                 hci_stack->hci_transport->set_baudrate(baud_rate);
1747             }
1748             if (need_addr_change){
1749                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1750                 return;
1751             }
1752             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1753             return;
1754         case HCI_INIT_W4_SET_BD_ADDR:
1755             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1756             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1757             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1758                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1759                 return;
1760             }
1761             // skipping st warm boot
1762             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1763             return;
1764         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1765             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1766             return;
1767 #endif
1768         case HCI_INIT_W4_READ_BD_ADDR:
1769             // only read buffer size if supported
1770             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1771                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1772                 return;
1773             }
1774             // skipping read buffer size
1775             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1776             return;
1777         case HCI_INIT_W4_SET_EVENT_MASK:
1778             // skip Classic init commands for LE only chipsets
1779             if (!hci_classic_supported()){
1780 #ifdef ENABLE_BLE
1781                 if (hci_le_supported()){
1782                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1783                     return;
1784                 }
1785 #endif
1786                 log_error("Neither BR/EDR nor LE supported");
1787                 hci_init_done();
1788                 return;
1789             }
1790             if (!gap_ssp_supported()){
1791                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1792                 return;
1793             }
1794             break;
1795 #ifdef ENABLE_BLE
1796         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1797             // skip write le host if not supported (e.g. on LE only EM9301)
1798             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1799             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1800             return;
1801 
1802 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1803         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1804             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1805             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1806                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1807                 return;
1808             }
1809             // explicit fall through to reduce repetitions
1810 
1811 #ifdef ENABLE_LE_CENTRAL
1812             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1813 #else
1814             hci_init_done();
1815 #endif
1816             return;
1817 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1818 
1819 #endif  /* ENABLE_BLE */
1820 
1821         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1822             // skip write secure connections host support if not supported or disabled
1823             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1824                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1825                 return;
1826             }
1827             break;
1828 
1829 #ifdef ENABLE_SCO_OVER_HCI
1830         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1831             // skip write synchronous flow control if not supported
1832             if (hci_stack->local_supported_commands[0] & 0x04) break;
1833             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1834 
1835             /* fall through */
1836 
1837         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1838             // skip write default erroneous data reporting if not supported
1839             if (hci_stack->local_supported_commands[0] & 0x08) break;
1840             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1841 
1842             /* fall through */
1843 
1844         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1845             // skip bcm set sco pcm config on non-Broadcom chipsets
1846             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1847             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1848 
1849             /* fall through */
1850 
1851         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1852             if (!hci_le_supported()){
1853                 // SKIP LE init for Classic only configuration
1854                 hci_init_done();
1855                 return;
1856             }
1857             break;
1858 
1859 #else /* !ENABLE_SCO_OVER_HCI */
1860 
1861         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1862 #ifdef ENABLE_BLE
1863             if (hci_le_supported()){
1864                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1865                 return;
1866             }
1867 #endif
1868             // SKIP LE init for Classic only configuration
1869             hci_init_done();
1870             return;
1871 #endif /* ENABLE_SCO_OVER_HCI */
1872 
1873 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1874 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1875         // Response to command before init done state -> init done
1876         case (HCI_INIT_DONE-1):
1877             hci_init_done();
1878             return;
1879 #endif
1880 
1881         default:
1882             break;
1883     }
1884     hci_initializing_next_state();
1885 }
1886 
1887 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1888     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1889     bd_addr_t bd_address;
1890     (void)memcpy(&bd_address, conn->address, 6);
1891 
1892 #ifdef ENABLE_CLASSIC
1893     // cache needed data
1894     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1895 #endif
1896 
1897     // connection failed, remove entry
1898     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1899     btstack_memory_hci_connection_free( conn );
1900 
1901 #ifdef ENABLE_CLASSIC
1902     // notify client if dedicated bonding
1903     if (notify_dedicated_bonding_failed){
1904         log_info("hci notify_dedicated_bonding_failed");
1905         hci_emit_dedicated_bonding_result(bd_address, status);
1906     }
1907 
1908     // if authentication error, also delete link key
1909     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1910         gap_drop_link_key_for_bd_addr(bd_address);
1911     }
1912 #else
1913     UNUSED(status);
1914 #endif
1915 }
1916 
1917 #ifdef ENABLE_CLASSIC
1918 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1919     // SSP Controller
1920     if (features[6] & (1 << 3)){
1921         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1922     }
1923     // eSCO
1924     if (features[3] & (1<<7)){
1925         conn->remote_supported_features[0] |= 1;
1926     }
1927     // Extended features
1928     if (features[7] & (1<<7)){
1929         conn->remote_supported_features[0] |= 2;
1930     }
1931 }
1932 
1933 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1934     // SSP Host
1935     if (features[0] & (1 << 0)){
1936         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1937     }
1938     // SC Host
1939     if (features[0] & (1 << 3)){
1940         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1941     }
1942 }
1943 
1944 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1945     // SC Controller
1946     if (features[1] & (1 << 0)){
1947         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1948     }
1949 }
1950 
1951 static void hci_handle_remote_features_received(hci_connection_t * conn){
1952     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1953     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1954     if (conn->bonding_flags & BONDING_DEDICATED){
1955         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1956     }
1957 }
1958 #endif
1959 
1960 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1961     // handle BT initialization
1962     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1963         hci_initializing_event_handler(packet, size);
1964     }
1965 
1966     // help with BT sleep
1967     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1968         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1969         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1970         hci_initializing_next_state();
1971     }
1972 }
1973 
1974 #ifdef ENABLE_CLASSIC
1975 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1976     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1977     conn->encryption_key_size = encryption_key_size;
1978 
1979     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1980         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1981         return;
1982     }
1983 
1984     // Request Authentication if not already done
1985     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1986     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1987 }
1988 #endif
1989 
1990 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1991     UNUSED(size);
1992 
1993     uint16_t manufacturer;
1994 #ifdef ENABLE_CLASSIC
1995     hci_con_handle_t handle;
1996     hci_connection_t * conn;
1997     uint8_t status;
1998 #endif
1999     // get num cmd packets - limit to 1 to reduce complexity
2000     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2001 
2002     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2003     switch (opcode){
2004         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2005             if (packet[5]) break;
2006             // terminate, name 248 chars
2007             packet[6+248] = 0;
2008             log_info("local name: %s", &packet[6]);
2009             break;
2010         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2011             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2012             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2013                 uint16_t acl_len = little_endian_read_16(packet, 6);
2014                 uint16_t sco_len = packet[8];
2015 
2016                 // determine usable ACL/SCO payload size
2017                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2018                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2019 
2020                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2021                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2022 
2023                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2024                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2025                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2026             }
2027             break;
2028         case HCI_OPCODE_HCI_READ_RSSI:
2029             if (packet[5] == ERROR_CODE_SUCCESS){
2030                 uint8_t event[5];
2031                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2032                 event[1] = 3;
2033                 (void)memcpy(&event[2], &packet[6], 3);
2034                 hci_emit_event(event, sizeof(event), 1);
2035             }
2036             break;
2037 #ifdef ENABLE_BLE
2038         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2039             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2040             hci_stack->le_acl_packets_total_num = packet[8];
2041             // determine usable ACL payload size
2042             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2043                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2044             }
2045             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2046             break;
2047 #endif
2048 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2049         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2050             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2051             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2052             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);
2053             break;
2054 #endif
2055 #ifdef ENABLE_LE_CENTRAL
2056         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2057             hci_stack->le_whitelist_capacity = packet[6];
2058             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2059             break;
2060 #endif
2061         case HCI_OPCODE_HCI_READ_BD_ADDR:
2062             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2063             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));
2064 #ifdef ENABLE_CLASSIC
2065             if (hci_stack->link_key_db){
2066                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2067             }
2068 #endif
2069             break;
2070 #ifdef ENABLE_CLASSIC
2071         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2072             hci_emit_discoverable_enabled(hci_stack->discoverable);
2073             break;
2074         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2075             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2076                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2077                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2078                 hci_emit_event(event, sizeof(event), 1);
2079             }
2080             break;
2081 #endif
2082         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2083             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2084 
2085 #ifdef ENABLE_CLASSIC
2086             // determine usable ACL packet types based on host buffer size and supported features
2087             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2088             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2089 #endif
2090             // Classic/LE
2091             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2092             break;
2093         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2094             manufacturer = little_endian_read_16(packet, 10);
2095             // map Cypress to Broadcom
2096             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2097                 log_info("Treat Cypress as Broadcom");
2098                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2099                 little_endian_store_16(packet, 10, manufacturer);
2100             }
2101             hci_stack->manufacturer = manufacturer;
2102             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2103             break;
2104         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2105             hci_stack->local_supported_commands[0] =
2106                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2107                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2108                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2109                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2110                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2111                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2112                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2113                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2114             hci_stack->local_supported_commands[1] =
2115                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2116                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2117                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u);   // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2118             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2119             break;
2120 #ifdef ENABLE_CLASSIC
2121         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2122             if (packet[5]) return;
2123             hci_stack->synchronous_flow_control_enabled = 1;
2124             break;
2125         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2126             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2127             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2128             conn   = hci_connection_for_handle(handle);
2129             if (conn != NULL) {
2130                 uint8_t key_size = 0;
2131                 if (status == 0){
2132                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2133                     log_info("Handle %04x key Size: %u", handle, key_size);
2134                 } else {
2135                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2136                 }
2137                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2138             }
2139             break;
2140 #endif
2141         default:
2142             break;
2143     }
2144 }
2145 
2146 #ifdef ENABLE_BLE
2147 static void event_handle_le_connection_complete(const uint8_t * packet){
2148 	bd_addr_t addr;
2149 	bd_addr_type_t addr_type;
2150 	hci_connection_t * conn;
2151 
2152 	// Connection management
2153 	reverse_bd_addr(&packet[8], addr);
2154 	addr_type = (bd_addr_type_t)packet[7];
2155 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2156 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2157 
2158 #ifdef ENABLE_LE_CENTRAL
2159 	// handle error: error is reported only to the initiator -> outgoing connection
2160 	if (packet[3]){
2161 
2162 		// handle cancelled outgoing connection
2163 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2164 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2165 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2166 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2167 			// whitelist connect
2168 			if (hci_is_le_connection_type(addr_type)){
2169 				hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2170 				hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2171 			}
2172 			// get outgoing connection conn struct for direct connect
2173 			conn = gap_get_outgoing_connection();
2174 		}
2175 
2176 		// outgoing le connection establishment is done
2177 		if (conn){
2178 			// remove entry
2179 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2180 			btstack_memory_hci_connection_free( conn );
2181 		}
2182 		return;
2183 	}
2184 #endif
2185 
2186 	// on success, both hosts receive connection complete event
2187 	if (packet[6] == HCI_ROLE_MASTER){
2188 #ifdef ENABLE_LE_CENTRAL
2189 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2190 		// note: no hci_connection_t object exists yet for connect with whitelist
2191 		if (hci_is_le_connection_type(addr_type)){
2192 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2193 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2194 		}
2195 #endif
2196 	} else {
2197 #ifdef ENABLE_LE_PERIPHERAL
2198 		// if we're slave, it was an incoming connection, advertisements have stopped
2199 		hci_stack->le_advertisements_active = false;
2200 #endif
2201 	}
2202 
2203 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2204 	if (!conn){
2205 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2206 	}
2207 
2208 	// no memory, sorry.
2209 	if (!conn){
2210 		return;
2211 	}
2212 
2213 	conn->state = OPEN;
2214 	conn->role  = packet[6];
2215 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2216 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2217 
2218 #ifdef ENABLE_LE_PERIPHERAL
2219 	if (packet[6] == HCI_ROLE_SLAVE){
2220 		hci_update_advertisements_enabled_for_current_roles();
2221 	}
2222 #endif
2223 
2224 	// TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2225 
2226 	// restart timer
2227 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2228 	// btstack_run_loop_add_timer(&conn->timeout);
2229 
2230 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2231 
2232 	hci_emit_nr_connections_changed();
2233 }
2234 #endif
2235 
2236 static void event_handler(uint8_t *packet, uint16_t size){
2237 
2238     uint16_t event_length = packet[1];
2239 
2240     // assert packet is complete
2241     if (size != (event_length + 2u)){
2242         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2243         return;
2244     }
2245 
2246     bd_addr_t addr;
2247     bd_addr_type_t addr_type;
2248     hci_con_handle_t handle;
2249     hci_connection_t * conn;
2250     int i;
2251     int create_connection_cmd;
2252 
2253 #ifdef ENABLE_CLASSIC
2254     uint8_t link_type;
2255 #endif
2256 
2257     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2258 
2259     switch (hci_event_packet_get_type(packet)) {
2260 
2261         case HCI_EVENT_COMMAND_COMPLETE:
2262             handle_command_complete_event(packet, size);
2263             break;
2264 
2265         case HCI_EVENT_COMMAND_STATUS:
2266             // get num cmd packets - limit to 1 to reduce complexity
2267             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2268 
2269             // check command status to detected failed outgoing connections
2270             create_connection_cmd = 0;
2271 #ifdef ENABLE_CLASSIC
2272             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2273                 create_connection_cmd = 1;
2274             }
2275 #endif
2276 #ifdef ENABLE_LE_CENTRAL
2277             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2278                 create_connection_cmd = 1;
2279             }
2280 #endif
2281             if (create_connection_cmd) {
2282                 uint8_t status = hci_event_command_status_get_status(packet);
2283                 addr_type = hci_stack->outgoing_addr_type;
2284                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2285                 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);
2286 
2287                 // reset outgoing address info
2288                 memset(hci_stack->outgoing_addr, 0, 6);
2289                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2290 
2291                 // on error
2292                 if (status != ERROR_CODE_SUCCESS){
2293 #ifdef ENABLE_LE_CENTRAL
2294                     if (hci_is_le_connection_type(addr_type)){
2295                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2296                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2297                     }
2298 #endif
2299                     // error => outgoing connection failed
2300                     if (conn != NULL){
2301                         hci_handle_connection_failed(conn, status);
2302                     }
2303                 }
2304             }
2305             break;
2306 
2307         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2308             if (size < 3) return;
2309             uint16_t num_handles = packet[2];
2310             if (size != (3u + num_handles * 4u)) return;
2311             uint16_t offset = 3;
2312             for (i=0; i<num_handles;i++){
2313                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2314                 offset += 2u;
2315                 uint16_t num_packets = little_endian_read_16(packet, offset);
2316                 offset += 2u;
2317 
2318                 conn = hci_connection_for_handle(handle);
2319                 if (!conn){
2320                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2321                     continue;
2322                 }
2323 
2324                 if (conn->num_packets_sent >= num_packets){
2325                     conn->num_packets_sent -= num_packets;
2326                 } else {
2327                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2328                     conn->num_packets_sent = 0;
2329                 }
2330                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2331 
2332 #ifdef ENABLE_CLASSIC
2333                 // For SCO, we do the can_send_now_check here
2334                 hci_notify_if_sco_can_send_now();
2335 #endif
2336             }
2337             break;
2338         }
2339 
2340 #ifdef ENABLE_CLASSIC
2341         case HCI_EVENT_INQUIRY_COMPLETE:
2342             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2343                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2344                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2345                 hci_emit_event(event, sizeof(event), 1);
2346             }
2347             break;
2348         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2349             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2350                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2351             }
2352             break;
2353         case HCI_EVENT_CONNECTION_REQUEST:
2354             reverse_bd_addr(&packet[2], addr);
2355             if (hci_stack->gap_classic_accept_callback != NULL){
2356                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2357                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2358                     bd_addr_copy(hci_stack->decline_addr, addr);
2359                     break;
2360                 }
2361             }
2362 
2363             // TODO: eval COD 8-10
2364             link_type = packet[11];
2365             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2366             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2367             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2368             if (!conn) {
2369                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2370             }
2371             if (!conn) {
2372                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2373                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2374                 bd_addr_copy(hci_stack->decline_addr, addr);
2375                 break;
2376             }
2377             conn->role  = HCI_ROLE_SLAVE;
2378             conn->state = RECEIVED_CONNECTION_REQUEST;
2379             // store info about eSCO
2380             if (link_type == 0x02){
2381                 conn->remote_supported_features[0] |= 1;
2382             }
2383             hci_run();
2384             break;
2385 
2386         case HCI_EVENT_CONNECTION_COMPLETE:
2387             // Connection management
2388             reverse_bd_addr(&packet[5], addr);
2389             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2390             addr_type = BD_ADDR_TYPE_ACL;
2391             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2392             if (conn) {
2393                 if (!packet[2]){
2394                     conn->state = OPEN;
2395                     conn->con_handle = little_endian_read_16(packet, 3);
2396 
2397                     // queue get remote feature
2398                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2399 
2400                     // queue set supervision timeout if we're master
2401                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2402                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2403                     }
2404 
2405                     // restart timer
2406                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2407                     btstack_run_loop_add_timer(&conn->timeout);
2408 
2409                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2410 
2411                     hci_emit_nr_connections_changed();
2412                 } else {
2413                     // connection failed
2414                     hci_handle_connection_failed(conn, packet[2]);
2415                 }
2416             }
2417             break;
2418 
2419         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2420             reverse_bd_addr(&packet[5], addr);
2421             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2422             if (packet[2]){
2423                 // connection failed
2424                 break;
2425             }
2426             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2427             if (!conn) {
2428                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2429             }
2430             if (!conn) {
2431                 break;
2432             }
2433             conn->state = OPEN;
2434             conn->con_handle = little_endian_read_16(packet, 3);
2435 
2436 #ifdef ENABLE_SCO_OVER_HCI
2437             // update SCO
2438             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2439                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2440             }
2441             // trigger can send now
2442             if (hci_have_usb_transport()){
2443                 hci_stack->sco_can_send_now = 1;
2444             }
2445 #endif
2446             break;
2447 
2448         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2449             handle = little_endian_read_16(packet, 3);
2450             conn = hci_connection_for_handle(handle);
2451             if (!conn) break;
2452             if (!packet[2]){
2453                 const uint8_t * features = &packet[5];
2454                 hci_handle_remote_features_page_0(conn, features);
2455 
2456                 // read extended features if possible
2457                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2458                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2459                     break;
2460                 }
2461             }
2462             hci_handle_remote_features_received(conn);
2463             break;
2464 
2465         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2466             handle = little_endian_read_16(packet, 3);
2467             conn = hci_connection_for_handle(handle);
2468             if (!conn) break;
2469             // status = ok, page = 1
2470             if (!packet[2]) {
2471                 uint8_t page_number = packet[5];
2472                 uint8_t maximum_page_number = packet[6];
2473                 const uint8_t * features = &packet[7];
2474                 bool done = false;
2475                 switch (page_number){
2476                     case 1:
2477                         hci_handle_remote_features_page_1(conn, features);
2478                         if (maximum_page_number >= 2){
2479                             // get Secure Connections (Controller) from Page 2 if available
2480                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2481                         } else {
2482                             // otherwise, assume SC (Controller) == SC (Host)
2483                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2484                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2485                             }
2486                             done = true;
2487                         }
2488                         break;
2489                     case 2:
2490                         hci_handle_remote_features_page_2(conn, features);
2491                         done = true;
2492                         break;
2493                     default:
2494                         break;
2495                 }
2496                 if (!done) break;
2497             }
2498             hci_handle_remote_features_received(conn);
2499             break;
2500 
2501         case HCI_EVENT_LINK_KEY_REQUEST:
2502             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2503             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2504             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2505             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2506             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2507             hci_run();
2508             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2509             return;
2510 
2511         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2512             reverse_bd_addr(&packet[2], addr);
2513             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2514             if (!conn) break;
2515             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2516             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2517             // Change Connection Encryption keeps link key type
2518             if (link_key_type != CHANGED_COMBINATION_KEY){
2519                 conn->link_key_type = link_key_type;
2520             }
2521             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2522             // still forward event to allow dismiss of pairing dialog
2523             break;
2524         }
2525 
2526         case HCI_EVENT_PIN_CODE_REQUEST:
2527             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2528             // non-bondable mode: pin code negative reply will be sent
2529             if (!hci_stack->bondable){
2530                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2531                 hci_run();
2532                 return;
2533             }
2534             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2535             if (!hci_stack->link_key_db) break;
2536             hci_event_pin_code_request_get_bd_addr(packet, addr);
2537             hci_stack->link_key_db->delete_link_key(addr);
2538             break;
2539 
2540         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2541             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2542             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2543             break;
2544 
2545         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2546             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2547             if (!hci_stack->ssp_auto_accept) break;
2548             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2549             break;
2550 
2551         case HCI_EVENT_USER_PASSKEY_REQUEST:
2552             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2553             if (!hci_stack->ssp_auto_accept) break;
2554             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2555             break;
2556         case HCI_EVENT_MODE_CHANGE:
2557             handle = hci_event_mode_change_get_handle(packet);
2558             conn = hci_connection_for_handle(handle);
2559             if (!conn) break;
2560             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2561             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2562             break;
2563 #endif
2564 
2565         case HCI_EVENT_ENCRYPTION_CHANGE:
2566             handle = hci_event_encryption_change_get_connection_handle(packet);
2567             conn = hci_connection_for_handle(handle);
2568             if (!conn) break;
2569             if (hci_event_encryption_change_get_status(packet) == 0u) {
2570                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2571                 if (encryption_enabled){
2572                     if (hci_is_le_connection(conn)){
2573                         // For LE, we accept connection as encrypted
2574                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2575                     }
2576 #ifdef ENABLE_CLASSIC
2577                     else {
2578                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2579                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2580                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2581                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2582                             log_info("SC during pairing, but only E0 now -> abort");
2583                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2584                             break;
2585                         }
2586 
2587                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2588                         if (connected_uses_aes_ccm){
2589                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2590                         }
2591 
2592                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2593                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2594                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2595                         } else {
2596                             // if not, pretend everything is perfect
2597                             hci_handle_read_encryption_key_size_complete(conn, 16);
2598                         }
2599                     }
2600 #endif
2601                 } else {
2602                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2603                 }
2604             }
2605 
2606             break;
2607 
2608 #ifdef ENABLE_CLASSIC
2609         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2610             handle = hci_event_authentication_complete_get_connection_handle(packet);
2611             conn = hci_connection_for_handle(handle);
2612             if (!conn) break;
2613 
2614             // ignore authentication event if we didn't request it
2615             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2616 
2617             // dedicated bonding: send result and disconnect
2618             if (conn->bonding_flags & BONDING_DEDICATED){
2619                 conn->bonding_flags &= ~BONDING_DEDICATED;
2620                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2621                 conn->bonding_status = packet[2];
2622                 break;
2623             }
2624 
2625             // authenticated only if auth status == 0
2626             if (hci_event_authentication_complete_get_status(packet) == 0){
2627                 // authenticated
2628                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2629 
2630                 // If link key sufficient for requested security and not already encrypted, start encryption
2631                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2632                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2633                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2634                     break;
2635                 }
2636             }
2637 
2638             // emit updated security level
2639             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2640             break;
2641 #endif
2642 
2643         // HCI_EVENT_DISCONNECTION_COMPLETE
2644         // has been split, to first notify stack before shutting connection down
2645         // see end of function, too.
2646         case HCI_EVENT_DISCONNECTION_COMPLETE:
2647             if (packet[2]) break;   // status != 0
2648             handle = little_endian_read_16(packet, 3);
2649             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2650             if (hci_stack->acl_fragmentation_total_size > 0u) {
2651                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2652                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2653                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2654                     hci_stack->acl_fragmentation_total_size = 0;
2655                     hci_stack->acl_fragmentation_pos = 0;
2656                     if (release_buffer){
2657                         hci_release_packet_buffer();
2658                     }
2659                 }
2660             }
2661 
2662             conn = hci_connection_for_handle(handle);
2663             if (!conn) break;
2664             // mark connection for shutdown
2665             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2666 
2667             // emit dedicatd bonding event
2668             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2669                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2670             }
2671 
2672 #ifdef ENABLE_BLE
2673 #ifdef ENABLE_LE_PERIPHERAL
2674             // re-enable advertisements for le connections if active
2675             if (hci_is_le_connection(conn)){
2676                 hci_update_advertisements_enabled_for_current_roles();
2677             }
2678 #endif
2679 #endif
2680             break;
2681 
2682         case HCI_EVENT_HARDWARE_ERROR:
2683             log_error("Hardware Error: 0x%02x", packet[2]);
2684             if (hci_stack->hardware_error_callback){
2685                 (*hci_stack->hardware_error_callback)(packet[2]);
2686             } else {
2687                 // if no special requests, just reboot stack
2688                 hci_power_control_off();
2689                 hci_power_control_on();
2690             }
2691             break;
2692 
2693 #ifdef ENABLE_CLASSIC
2694         case HCI_EVENT_ROLE_CHANGE:
2695             if (packet[2]) break;   // status != 0
2696             reverse_bd_addr(&packet[3], addr);
2697             addr_type = BD_ADDR_TYPE_ACL;
2698             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2699             if (!conn) break;
2700             conn->role = packet[9];
2701             break;
2702 #endif
2703 
2704         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2705             // release packet buffer only for asynchronous transport and if there are not further fragements
2706             if (hci_transport_synchronous()) {
2707                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2708                 return; // instead of break: to avoid re-entering hci_run()
2709             }
2710             hci_stack->acl_fragmentation_tx_active = 0;
2711             if (hci_stack->acl_fragmentation_total_size) break;
2712             hci_release_packet_buffer();
2713 
2714             // L2CAP receives this event via the hci_emit_event below
2715 
2716 #ifdef ENABLE_CLASSIC
2717             // For SCO, we do the can_send_now_check here
2718             hci_notify_if_sco_can_send_now();
2719 #endif
2720             break;
2721 
2722 #ifdef ENABLE_CLASSIC
2723         case HCI_EVENT_SCO_CAN_SEND_NOW:
2724             // For SCO, we do the can_send_now_check here
2725             hci_stack->sco_can_send_now = 1;
2726             hci_notify_if_sco_can_send_now();
2727             return;
2728 
2729         // explode inquriy results for easier consumption
2730         case HCI_EVENT_INQUIRY_RESULT:
2731         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2732         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2733             gap_inquiry_explode(packet, size);
2734             break;
2735 #endif
2736 
2737 #ifdef ENABLE_BLE
2738         case HCI_EVENT_LE_META:
2739             switch (packet[2]){
2740 #ifdef ENABLE_LE_CENTRAL
2741                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2742                     // log_info("advertising report received");
2743                     if (!hci_stack->le_scanning_enabled) break;
2744                     le_handle_advertisement_report(packet, size);
2745                     break;
2746 #endif
2747                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2748 					event_handle_le_connection_complete(packet);
2749                     break;
2750 
2751                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2752                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2753                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2754                     conn = hci_connection_for_handle(handle);
2755                     if (!conn) break;
2756                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2757                     break;
2758 
2759                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2760                     // connection
2761                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2762                     conn = hci_connection_for_handle(handle);
2763                     if (conn) {
2764                         // read arguments
2765                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2766                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2767                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2768                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2769 
2770                         // validate against current connection parameter range
2771                         le_connection_parameter_range_t existing_range;
2772                         gap_get_connection_parameter_range(&existing_range);
2773                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2774                         if (update_parameter){
2775                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2776                             conn->le_conn_interval_min = le_conn_interval_min;
2777                             conn->le_conn_interval_max = le_conn_interval_max;
2778                             conn->le_conn_latency = le_conn_latency;
2779                             conn->le_supervision_timeout = le_supervision_timeout;
2780                         } else {
2781                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
2782                         }
2783                     }
2784                     break;
2785 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2786                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2787                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2788                     conn = hci_connection_for_handle(handle);
2789                     if (conn) {
2790                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2791                     }
2792                     break;
2793 #endif
2794                 default:
2795                     break;
2796             }
2797             break;
2798 #endif
2799         case HCI_EVENT_VENDOR_SPECIFIC:
2800             // Vendor specific commands often create vendor specific event instead of num completed packets
2801             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2802             switch (hci_stack->manufacturer){
2803                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2804                     hci_stack->num_cmd_packets = 1;
2805                     break;
2806                 default:
2807                     break;
2808             }
2809             break;
2810         default:
2811             break;
2812     }
2813 
2814     handle_event_for_current_stack_state(packet, size);
2815 
2816     // notify upper stack
2817 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2818 
2819     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2820     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
2821 		handle = little_endian_read_16(packet, 3);
2822 		hci_connection_t * aConn = hci_connection_for_handle(handle);
2823 		// discard connection if app did not trigger a reconnect in the event handler
2824 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2825 			hci_shutdown_connection(aConn);
2826 		}
2827     }
2828 
2829 	// execute main loop
2830 	hci_run();
2831 }
2832 
2833 #ifdef ENABLE_CLASSIC
2834 
2835 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2836 static void sco_schedule_tx(hci_connection_t * conn);
2837 
2838 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2839     log_debug("SCO TX Timeout");
2840     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2841     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2842     if (!conn) return;
2843 
2844     // trigger send
2845     conn->sco_tx_ready = 1;
2846     // extra packet if CVSD but SCO buffer is too short
2847     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2848         conn->sco_tx_ready++;
2849     }
2850     hci_notify_if_sco_can_send_now();
2851 }
2852 
2853 
2854 #define SCO_TX_AFTER_RX_MS (6)
2855 
2856 static void sco_schedule_tx(hci_connection_t * conn){
2857 
2858     uint32_t now = btstack_run_loop_get_time_ms();
2859     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2860     int time_delta_ms = sco_tx_ms - now;
2861 
2862     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2863 
2864     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2865     btstack_run_loop_set_timer(timer, time_delta_ms);
2866     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2867     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2868     btstack_run_loop_add_timer(timer);
2869 }
2870 
2871 static void sco_handler(uint8_t * packet, uint16_t size){
2872     // lookup connection struct
2873     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2874     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2875     if (!conn) return;
2876 
2877     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2878     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2879         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2880             packet[2] = 0x3c;
2881             memmove(&packet[3], &packet[23], 63);
2882             size = 63;
2883         }
2884     }
2885 
2886     if (hci_have_usb_transport()){
2887         // Nothing to do
2888     } else {
2889         // 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);
2890         if (hci_stack->synchronous_flow_control_enabled == 0){
2891             uint32_t now = btstack_run_loop_get_time_ms();
2892 
2893             if (!conn->sco_rx_valid){
2894                 // ignore first 10 packets
2895                 conn->sco_rx_count++;
2896                 // log_debug("sco rx count %u", conn->sco_rx_count);
2897                 if (conn->sco_rx_count == 10) {
2898                     // use first timestamp as is and pretent it just started
2899                     conn->sco_rx_ms = now;
2900                     conn->sco_rx_valid = 1;
2901                     conn->sco_rx_count = 0;
2902                     sco_schedule_tx(conn);
2903                 }
2904             } else {
2905                 // track expected arrival timme
2906                 conn->sco_rx_count++;
2907                 conn->sco_rx_ms += 7;
2908                 int delta = (int32_t) (now - conn->sco_rx_ms);
2909                 if (delta > 0){
2910                     conn->sco_rx_ms++;
2911                 }
2912                 // log_debug("sco rx %u", conn->sco_rx_ms);
2913                 sco_schedule_tx(conn);
2914             }
2915         }
2916     }
2917     // deliver to app
2918     if (hci_stack->sco_packet_handler) {
2919         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2920     }
2921 
2922 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2923     conn->num_packets_completed++;
2924     hci_stack->host_completed_packets = 1;
2925     hci_run();
2926 #endif
2927 }
2928 #endif
2929 
2930 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2931     hci_dump_packet(packet_type, 1, packet, size);
2932     switch (packet_type) {
2933         case HCI_EVENT_PACKET:
2934             event_handler(packet, size);
2935             break;
2936         case HCI_ACL_DATA_PACKET:
2937             acl_handler(packet, size);
2938             break;
2939 #ifdef ENABLE_CLASSIC
2940         case HCI_SCO_DATA_PACKET:
2941             sco_handler(packet, size);
2942             break;
2943 #endif
2944         default:
2945             break;
2946     }
2947 }
2948 
2949 /**
2950  * @brief Add event packet handler.
2951  */
2952 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2953     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2954 }
2955 
2956 
2957 /** Register HCI packet handlers */
2958 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2959     hci_stack->acl_packet_handler = handler;
2960 }
2961 
2962 #ifdef ENABLE_CLASSIC
2963 /**
2964  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2965  */
2966 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2967     hci_stack->sco_packet_handler = handler;
2968 }
2969 #endif
2970 
2971 static void hci_state_reset(void){
2972     // no connections yet
2973     hci_stack->connections = NULL;
2974 
2975     // keep discoverable/connectable as this has been requested by the client(s)
2976     // hci_stack->discoverable = 0;
2977     // hci_stack->connectable = 0;
2978     // hci_stack->bondable = 1;
2979     // hci_stack->own_addr_type = 0;
2980 
2981     // buffer is free
2982     hci_stack->hci_packet_buffer_reserved = 0;
2983 
2984     // no pending cmds
2985     hci_stack->decline_reason = 0;
2986     hci_stack->new_scan_enable_value = 0xff;
2987 
2988     hci_stack->secure_connections_active = false;
2989 
2990     // LE
2991 #ifdef ENABLE_BLE
2992     memset(hci_stack->le_random_address, 0, 6);
2993     hci_stack->le_random_address_set = 0;
2994 #endif
2995 #ifdef ENABLE_LE_CENTRAL
2996     hci_stack->le_scanning_active  = 0;
2997     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2998     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2999     hci_stack->le_whitelist_capacity = 0;
3000 #endif
3001 }
3002 
3003 #ifdef ENABLE_CLASSIC
3004 /**
3005  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3006  */
3007 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3008     // store and open remote device db
3009     hci_stack->link_key_db = link_key_db;
3010     if (hci_stack->link_key_db) {
3011         hci_stack->link_key_db->open();
3012     }
3013 }
3014 #endif
3015 
3016 void hci_init(const hci_transport_t *transport, const void *config){
3017 
3018 #ifdef HAVE_MALLOC
3019     if (!hci_stack) {
3020         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3021     }
3022 #else
3023     hci_stack = &hci_stack_static;
3024 #endif
3025     memset(hci_stack, 0, sizeof(hci_stack_t));
3026 
3027     // reference to use transport layer implementation
3028     hci_stack->hci_transport = transport;
3029 
3030     // reference to used config
3031     hci_stack->config = config;
3032 
3033     // setup pointer for outgoing packet buffer
3034     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3035 
3036     // max acl payload size defined in config.h
3037     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3038 
3039     // register packet handlers with transport
3040     transport->register_packet_handler(&packet_handler);
3041 
3042     hci_stack->state = HCI_STATE_OFF;
3043 
3044     // class of device
3045     hci_stack->class_of_device = 0x007a020c; // Smartphone
3046 
3047     // bondable by default
3048     hci_stack->bondable = 1;
3049 
3050 #ifdef ENABLE_CLASSIC
3051     // classic name
3052     hci_stack->local_name = default_classic_name;
3053 
3054     // Master slave policy
3055     hci_stack->master_slave_policy = 1;
3056 
3057     // Allow Role Switch
3058     hci_stack->allow_role_switch = 1;
3059 
3060     // Default / minimum security level = 2
3061     hci_stack->gap_security_level = LEVEL_2;
3062 
3063     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3064     hci_stack->gap_required_encyrption_key_size = 7;
3065 #endif
3066 
3067     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3068     hci_stack->ssp_enable = 1;
3069     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3070     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3071     hci_stack->ssp_auto_accept = 1;
3072 
3073     // Secure Connections: enable (requires support from Controller)
3074     hci_stack->secure_connections_enable = true;
3075 
3076     // voice setting - signed 16 bit pcm data with CVSD over the air
3077     hci_stack->sco_voice_setting = 0x60;
3078 
3079 #ifdef ENABLE_LE_CENTRAL
3080     // connection parameter to use for outgoing connections
3081     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3082     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3083     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3084     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3085     hci_stack->le_connection_latency      = 4;         // 4
3086     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3087     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3088     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3089 
3090     // default LE Scanning
3091     hci_stack->le_scan_type     =   0x1; // active
3092     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3093     hci_stack->le_scan_window   =  0x30; //  30 ms
3094 #endif
3095 
3096 #ifdef ENABLE_LE_PERIPHERAL
3097     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3098 #endif
3099 
3100     // connection parameter range used to answer connection parameter update requests in l2cap
3101     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3102     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3103     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3104     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3105     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3106     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3107 
3108     hci_state_reset();
3109 }
3110 
3111 /**
3112  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3113  */
3114 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3115     hci_stack->chipset = chipset_driver;
3116 
3117     // reset chipset driver - init is also called on power_up
3118     if (hci_stack->chipset && hci_stack->chipset->init){
3119         hci_stack->chipset->init(hci_stack->config);
3120     }
3121 }
3122 
3123 /**
3124  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3125  */
3126 void hci_set_control(const btstack_control_t *hardware_control){
3127     // references to used control implementation
3128     hci_stack->control = hardware_control;
3129     // init with transport config
3130     hardware_control->init(hci_stack->config);
3131 }
3132 
3133 void hci_close(void){
3134     // close remote device db
3135     if (hci_stack->link_key_db) {
3136         hci_stack->link_key_db->close();
3137     }
3138 
3139     btstack_linked_list_iterator_t lit;
3140     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3141     while (btstack_linked_list_iterator_has_next(&lit)){
3142         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3143         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3144         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3145         hci_shutdown_connection(connection);
3146     }
3147 
3148     hci_power_control(HCI_POWER_OFF);
3149 
3150 #ifdef HAVE_MALLOC
3151     free(hci_stack);
3152 #endif
3153     hci_stack = NULL;
3154 }
3155 
3156 #ifdef ENABLE_CLASSIC
3157 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3158     // validate ranage and set
3159     if (encryption_key_size < 7)  return;
3160     if (encryption_key_size > 16) return;
3161     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3162 }
3163 
3164 void gap_set_security_level(gap_security_level_t security_level){
3165     hci_stack->gap_security_level = security_level;
3166 }
3167 
3168 gap_security_level_t gap_get_security_level(void){
3169     return hci_stack->gap_security_level;
3170 }
3171 #endif
3172 
3173 #ifdef ENABLE_CLASSIC
3174 void gap_set_class_of_device(uint32_t class_of_device){
3175     hci_stack->class_of_device = class_of_device;
3176 }
3177 
3178 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3179     hci_stack->default_link_policy_settings = default_link_policy_settings;
3180 }
3181 
3182 void gap_set_allow_role_switch(bool allow_role_switch){
3183     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3184 }
3185 
3186 uint8_t hci_get_allow_role_switch(void){
3187     return  hci_stack->allow_role_switch;
3188 }
3189 
3190 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3191     hci_stack->link_supervision_timeout = link_supervision_timeout;
3192 }
3193 
3194 void hci_disable_l2cap_timeout_check(void){
3195     disable_l2cap_timeouts = 1;
3196 }
3197 #endif
3198 
3199 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3200 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3201 void hci_set_bd_addr(bd_addr_t addr){
3202     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3203     hci_stack->custom_bd_addr_set = 1;
3204 }
3205 #endif
3206 
3207 // State-Module-Driver overview
3208 // state                    module  low-level
3209 // HCI_STATE_OFF             off      close
3210 // HCI_STATE_INITIALIZING,   on       open
3211 // HCI_STATE_WORKING,        on       open
3212 // HCI_STATE_HALTING,        on       open
3213 // HCI_STATE_SLEEPING,    off/sleep   close
3214 // HCI_STATE_FALLING_ASLEEP  on       open
3215 
3216 static int hci_power_control_on(void){
3217 
3218     // power on
3219     int err = 0;
3220     if (hci_stack->control && hci_stack->control->on){
3221         err = (*hci_stack->control->on)();
3222     }
3223     if (err){
3224         log_error( "POWER_ON failed");
3225         hci_emit_hci_open_failed();
3226         return err;
3227     }
3228 
3229     // int chipset driver
3230     if (hci_stack->chipset && hci_stack->chipset->init){
3231         hci_stack->chipset->init(hci_stack->config);
3232     }
3233 
3234     // init transport
3235     if (hci_stack->hci_transport->init){
3236         hci_stack->hci_transport->init(hci_stack->config);
3237     }
3238 
3239     // open transport
3240     err = hci_stack->hci_transport->open();
3241     if (err){
3242         log_error( "HCI_INIT failed, turning Bluetooth off again");
3243         if (hci_stack->control && hci_stack->control->off){
3244             (*hci_stack->control->off)();
3245         }
3246         hci_emit_hci_open_failed();
3247         return err;
3248     }
3249     return 0;
3250 }
3251 
3252 static void hci_power_control_off(void){
3253 
3254     log_info("hci_power_control_off");
3255 
3256     // close low-level device
3257     hci_stack->hci_transport->close();
3258 
3259     log_info("hci_power_control_off - hci_transport closed");
3260 
3261     // power off
3262     if (hci_stack->control && hci_stack->control->off){
3263         (*hci_stack->control->off)();
3264     }
3265 
3266     log_info("hci_power_control_off - control closed");
3267 
3268     hci_stack->state = HCI_STATE_OFF;
3269 }
3270 
3271 static void hci_power_control_sleep(void){
3272 
3273     log_info("hci_power_control_sleep");
3274 
3275 #if 0
3276     // don't close serial port during sleep
3277 
3278     // close low-level device
3279     hci_stack->hci_transport->close(hci_stack->config);
3280 #endif
3281 
3282     // sleep mode
3283     if (hci_stack->control && hci_stack->control->sleep){
3284         (*hci_stack->control->sleep)();
3285     }
3286 
3287     hci_stack->state = HCI_STATE_SLEEPING;
3288 }
3289 
3290 static int hci_power_control_wake(void){
3291 
3292     log_info("hci_power_control_wake");
3293 
3294     // wake on
3295     if (hci_stack->control && hci_stack->control->wake){
3296         (*hci_stack->control->wake)();
3297     }
3298 
3299 #if 0
3300     // open low-level device
3301     int err = hci_stack->hci_transport->open(hci_stack->config);
3302     if (err){
3303         log_error( "HCI_INIT failed, turning Bluetooth off again");
3304         if (hci_stack->control && hci_stack->control->off){
3305             (*hci_stack->control->off)();
3306         }
3307         hci_emit_hci_open_failed();
3308         return err;
3309     }
3310 #endif
3311 
3312     return 0;
3313 }
3314 
3315 static void hci_power_transition_to_initializing(void){
3316     // set up state machine
3317     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3318     hci_stack->hci_packet_buffer_reserved = 0;
3319     hci_stack->state = HCI_STATE_INITIALIZING;
3320     hci_stack->substate = HCI_INIT_SEND_RESET;
3321 }
3322 
3323 int hci_power_control(HCI_POWER_MODE power_mode){
3324 
3325     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3326 
3327     int err = 0;
3328     switch (hci_stack->state){
3329 
3330         case HCI_STATE_OFF:
3331             switch (power_mode){
3332                 case HCI_POWER_ON:
3333                     err = hci_power_control_on();
3334                     if (err) {
3335                         log_error("hci_power_control_on() error %d", err);
3336                         return err;
3337                     }
3338                     hci_power_transition_to_initializing();
3339                     break;
3340                 case HCI_POWER_OFF:
3341                     // do nothing
3342                     break;
3343                 case HCI_POWER_SLEEP:
3344                     // do nothing (with SLEEP == OFF)
3345                     break;
3346                 default:
3347                     btstack_assert(false);
3348                     break;
3349             }
3350             break;
3351 
3352         case HCI_STATE_INITIALIZING:
3353             switch (power_mode){
3354                 case HCI_POWER_ON:
3355                     // do nothing
3356                     break;
3357                 case HCI_POWER_OFF:
3358                     // no connections yet, just turn it off
3359                     hci_power_control_off();
3360                     break;
3361                 case HCI_POWER_SLEEP:
3362                     // no connections yet, just turn it off
3363                     hci_power_control_sleep();
3364                     break;
3365                 default:
3366                     btstack_assert(false);
3367                     break;
3368             }
3369             break;
3370 
3371         case HCI_STATE_WORKING:
3372             switch (power_mode){
3373                 case HCI_POWER_ON:
3374                     // do nothing
3375                     break;
3376                 case HCI_POWER_OFF:
3377                     // see hci_run
3378                     hci_stack->state = HCI_STATE_HALTING;
3379                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3380                     break;
3381                 case HCI_POWER_SLEEP:
3382                     // see hci_run
3383                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3384                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3385                     break;
3386                 default:
3387                     btstack_assert(false);
3388                     break;
3389             }
3390             break;
3391 
3392         case HCI_STATE_HALTING:
3393             switch (power_mode){
3394                 case HCI_POWER_ON:
3395                     hci_power_transition_to_initializing();
3396                     break;
3397                 case HCI_POWER_OFF:
3398                     // do nothing
3399                     break;
3400                 case HCI_POWER_SLEEP:
3401                     // see hci_run
3402                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3403                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3404                     break;
3405                 default:
3406                     btstack_assert(false);
3407                     break;
3408             }
3409             break;
3410 
3411         case HCI_STATE_FALLING_ASLEEP:
3412             switch (power_mode){
3413                 case HCI_POWER_ON:
3414 
3415 #ifdef HAVE_PLATFORM_IPHONE_OS
3416                     // nothing to do, if H4 supports power management
3417                     if (btstack_control_iphone_power_management_enabled()){
3418                         hci_stack->state = HCI_STATE_INITIALIZING;
3419                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3420                         break;
3421                     }
3422 #endif
3423                     hci_power_transition_to_initializing();
3424                     break;
3425                 case HCI_POWER_OFF:
3426                     // see hci_run
3427                     hci_stack->state = HCI_STATE_HALTING;
3428                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3429                     break;
3430                 case HCI_POWER_SLEEP:
3431                     // do nothing
3432                     break;
3433                 default:
3434                     btstack_assert(false);
3435                     break;
3436             }
3437             break;
3438 
3439         case HCI_STATE_SLEEPING:
3440             switch (power_mode){
3441                 case HCI_POWER_ON:
3442 
3443 #ifdef HAVE_PLATFORM_IPHONE_OS
3444                     // nothing to do, if H4 supports power management
3445                     if (btstack_control_iphone_power_management_enabled()){
3446                         hci_stack->state = HCI_STATE_INITIALIZING;
3447                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3448                         hci_update_scan_enable();
3449                         break;
3450                     }
3451 #endif
3452                     err = hci_power_control_wake();
3453                     if (err) return err;
3454                     hci_power_transition_to_initializing();
3455                     break;
3456                 case HCI_POWER_OFF:
3457                     hci_stack->state = HCI_STATE_HALTING;
3458                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3459                     break;
3460                 case HCI_POWER_SLEEP:
3461                     // do nothing
3462                     break;
3463                 default:
3464                     btstack_assert(false);
3465                     break;
3466             }
3467             break;
3468 
3469         default:
3470             btstack_assert(false);
3471             break;
3472     }
3473 
3474     // create internal event
3475 	hci_emit_state();
3476 
3477 	// trigger next/first action
3478 	hci_run();
3479 
3480     return 0;
3481 }
3482 
3483 
3484 #ifdef ENABLE_CLASSIC
3485 
3486 static void hci_update_scan_enable(void){
3487     // 2 = page scan, 1 = inq scan
3488     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3489     hci_run();
3490 }
3491 
3492 void gap_discoverable_control(uint8_t enable){
3493     if (enable) enable = 1; // normalize argument
3494 
3495     if (hci_stack->discoverable == enable){
3496         hci_emit_discoverable_enabled(hci_stack->discoverable);
3497         return;
3498     }
3499 
3500     hci_stack->discoverable = enable;
3501     hci_update_scan_enable();
3502 }
3503 
3504 void gap_connectable_control(uint8_t enable){
3505     if (enable) enable = 1; // normalize argument
3506 
3507     // don't emit event
3508     if (hci_stack->connectable == enable) return;
3509 
3510     hci_stack->connectable = enable;
3511     hci_update_scan_enable();
3512 }
3513 #endif
3514 
3515 void gap_local_bd_addr(bd_addr_t address_buffer){
3516     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3517 }
3518 
3519 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3520 static void hci_host_num_completed_packets(void){
3521 
3522     // create packet manually as arrays are not supported and num_commands should not get reduced
3523     hci_reserve_packet_buffer();
3524     uint8_t * packet = hci_get_outgoing_packet_buffer();
3525 
3526     uint16_t size = 0;
3527     uint16_t num_handles = 0;
3528     packet[size++] = 0x35;
3529     packet[size++] = 0x0c;
3530     size++;  // skip param len
3531     size++;  // skip num handles
3532 
3533     // add { handle, packets } entries
3534     btstack_linked_item_t * it;
3535     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3536         hci_connection_t * connection = (hci_connection_t *) it;
3537         if (connection->num_packets_completed){
3538             little_endian_store_16(packet, size, connection->con_handle);
3539             size += 2;
3540             little_endian_store_16(packet, size, connection->num_packets_completed);
3541             size += 2;
3542             //
3543             num_handles++;
3544             connection->num_packets_completed = 0;
3545         }
3546     }
3547 
3548     packet[2] = size - 3;
3549     packet[3] = num_handles;
3550 
3551     hci_stack->host_completed_packets = 0;
3552 
3553     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3554     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3555 
3556     // release packet buffer for synchronous transport implementations
3557     if (hci_transport_synchronous()){
3558         hci_release_packet_buffer();
3559         hci_emit_transport_packet_sent();
3560     }
3561 }
3562 #endif
3563 
3564 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3565     UNUSED(ds);
3566     hci_stack->substate = HCI_HALTING_CLOSE;
3567     // allow packet handlers to defer final shutdown
3568     hci_emit_state();
3569     hci_run();
3570 }
3571 
3572 static bool hci_run_acl_fragments(void){
3573     if (hci_stack->acl_fragmentation_total_size > 0u) {
3574         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3575         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3576         if (connection) {
3577             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3578                 hci_send_acl_packet_fragments(connection);
3579                 return true;
3580             }
3581         } else {
3582             // connection gone -> discard further fragments
3583             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3584             hci_stack->acl_fragmentation_total_size = 0;
3585             hci_stack->acl_fragmentation_pos = 0;
3586         }
3587     }
3588     return false;
3589 }
3590 
3591 #ifdef ENABLE_CLASSIC
3592 static bool hci_run_general_gap_classic(void){
3593 
3594     // decline incoming connections
3595     if (hci_stack->decline_reason){
3596         uint8_t reason = hci_stack->decline_reason;
3597         hci_stack->decline_reason = 0;
3598         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3599         return true;
3600     }
3601     // send scan enable
3602     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3603         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3604         hci_stack->new_scan_enable_value = 0xff;
3605         return true;
3606     }
3607     // start/stop inquiry
3608     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3609         uint8_t duration = hci_stack->inquiry_state;
3610         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3611         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3612         return true;
3613     }
3614     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3615         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3616         hci_send_cmd(&hci_inquiry_cancel);
3617         return true;
3618     }
3619     // remote name request
3620     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3621         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3622         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3623                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3624         return true;
3625     }
3626     // pairing
3627     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3628         uint8_t state = hci_stack->gap_pairing_state;
3629         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3630         switch (state){
3631             case GAP_PAIRING_STATE_SEND_PIN:
3632                 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);
3633                 break;
3634             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3635                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3636                 break;
3637             case GAP_PAIRING_STATE_SEND_PASSKEY:
3638                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3639                 break;
3640             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3641                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3642                 break;
3643             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3644                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3645                 break;
3646             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3647                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3648                 break;
3649             default:
3650                 break;
3651         }
3652         return true;
3653     }
3654     return false;
3655 }
3656 #endif
3657 
3658 #ifdef ENABLE_BLE
3659 static bool hci_run_general_gap_le(void){
3660 
3661     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3662 
3663     if (hci_stack->state != HCI_STATE_WORKING) return false;
3664     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3665 
3666 
3667     // Phase 1: collect what to stop
3668 
3669     bool scanning_stop = false;
3670     bool connecting_stop = false;
3671     bool advertising_stop = false;
3672 
3673 #ifndef ENABLE_LE_CENTRAL
3674     UNUSED(scanning_stop);
3675     UNUSED(connecting_stop);
3676 #endif
3677 #ifndef ENABLE_LE_PERIPHERAL
3678     UNUSED(advertising_stop);
3679 #endif
3680 
3681     // check if whitelist needs modification
3682     bool whitelist_modification_pending = false;
3683     btstack_linked_list_iterator_t lit;
3684     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3685     while (btstack_linked_list_iterator_has_next(&lit)){
3686         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3687         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3688             whitelist_modification_pending = true;
3689             break;
3690         }
3691     }
3692     // check if resolving list needs modification
3693     bool resolving_list_modification_pending = false;
3694 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3695     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
3696 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
3697         resolving_list_modification_pending = true;
3698     }
3699 #endif
3700 
3701 #ifdef ENABLE_LE_CENTRAL
3702     // scanning control
3703     if (hci_stack->le_scanning_active) {
3704         // stop if:
3705         // - parameter change required
3706         // - it's disabled
3707         // - whitelist change required but used for scanning
3708         // - resolving list modified
3709         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3710         if ((hci_stack->le_scanning_param_update) ||
3711             !hci_stack->le_scanning_enabled ||
3712             scanning_uses_whitelist ||
3713             resolving_list_modification_pending){
3714 
3715             scanning_stop = true;
3716         }
3717     }
3718 #endif
3719 
3720 #ifdef ENABLE_LE_CENTRAL
3721     // connecting control
3722     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3723         // stop connecting if:
3724         // - connecting uses white and whitelist modification pending
3725         // - if it got disabled
3726         // - resolving list modified
3727         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3728         if ((connecting_uses_whitelist && whitelist_modification_pending) ||
3729             (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
3730             resolving_list_modification_pending) {
3731 
3732             connecting_stop = true;
3733         }
3734     }
3735 #endif
3736 
3737 #ifdef ENABLE_LE_PERIPHERAL
3738     // le advertisement control
3739     if (hci_stack->le_advertisements_active){
3740         // stop if:
3741         // - parameter change required
3742         // - it's disabled
3743         // - whitelist change required but used for advertisement filter policy
3744         // - resolving list modified
3745         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3746         if ((hci_stack->le_advertisements_todo != 0) ||
3747             !hci_stack->le_advertisements_enabled_for_current_roles ||
3748             (advertising_uses_whitelist & whitelist_modification_pending) ||
3749             resolving_list_modification_pending) {
3750 
3751             advertising_stop = true;
3752         }
3753     }
3754 #endif
3755 
3756 
3757     // Phase 2: stop everything that should be off during modifications
3758 
3759 #ifdef ENABLE_LE_CENTRAL
3760     if (scanning_stop){
3761         hci_stack->le_scanning_active = false;
3762         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3763         return true;
3764     }
3765 #endif
3766 
3767 #ifdef ENABLE_LE_CENTRAL
3768     if (connecting_stop){
3769         if (hci_stack->le_connecting_state != LE_CONNECTING_CANCEL){
3770             hci_send_cmd(&hci_le_create_connection_cancel);
3771             return true;
3772         }
3773     }
3774 #endif
3775 
3776 #ifdef ENABLE_LE_PERIPHERAL
3777     if (advertising_stop){
3778         hci_stack->le_advertisements_active = false;
3779         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3780         return true;
3781     }
3782 #endif
3783 
3784     // Phase 3: modify
3785 
3786 #ifdef ENABLE_LE_CENTRAL
3787     if (hci_stack->le_scanning_param_update){
3788         hci_stack->le_scanning_param_update = false;
3789         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3790                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3791         return true;
3792     }
3793 #endif
3794 
3795 #ifdef ENABLE_LE_PERIPHERAL
3796     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3797         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3798         hci_send_cmd(&hci_le_set_advertising_parameters,
3799                      hci_stack->le_advertisements_interval_min,
3800                      hci_stack->le_advertisements_interval_max,
3801                      hci_stack->le_advertisements_type,
3802                      hci_stack->le_own_addr_type,
3803                      hci_stack->le_advertisements_direct_address_type,
3804                      hci_stack->le_advertisements_direct_address,
3805                      hci_stack->le_advertisements_channel_map,
3806                      hci_stack->le_advertisements_filter_policy);
3807         return true;
3808     }
3809     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3810         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3811         uint8_t adv_data_clean[31];
3812         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3813         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3814                      hci_stack->le_advertisements_data_len);
3815         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3816         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3817         return true;
3818     }
3819     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3820         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3821         uint8_t scan_data_clean[31];
3822         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3823         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3824                      hci_stack->le_scan_response_data_len);
3825         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3826         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3827         return true;
3828     }
3829 #endif
3830 
3831 
3832 #ifdef ENABLE_LE_CENTRAL
3833     // if connect with whitelist was active and is not cancelled yet, wait until next time
3834     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
3835 #endif
3836 
3837     // LE Whitelist Management
3838     if (whitelist_modification_pending){
3839         // add/remove entries
3840         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3841         while (btstack_linked_list_iterator_has_next(&lit)){
3842             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3843 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3844 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3845 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
3846 				return true;
3847 			}
3848             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3849 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
3850                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
3851                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3852                 return true;
3853             }
3854             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
3855 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3856 				btstack_memory_whitelist_entry_free(entry);
3857             }
3858         }
3859     }
3860 
3861 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3862     // LE Resolving List Management
3863     if (resolving_list_supported) {
3864 		uint16_t i;
3865 		switch (hci_stack->le_resolving_list_state) {
3866 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
3867 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
3868 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
3869 				return true;
3870 			case LE_RESOLVING_LIST_READ_SIZE:
3871 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
3872 				hci_send_cmd(&hci_le_read_resolving_list_size);
3873 				return true;
3874 			case LE_RESOLVING_LIST_SEND_CLEAR:
3875 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
3876 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
3877 							  sizeof(hci_stack->le_resolving_list_add_entries));
3878 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
3879 							  sizeof(hci_stack->le_resolving_list_remove_entries));
3880 				hci_send_cmd(&hci_le_clear_resolving_list);
3881 				return true;
3882 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
3883 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3884 					uint8_t offset = i >> 3;
3885 					uint8_t mask = 1 << (i & 7);
3886 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
3887 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
3888 					bd_addr_t peer_identity_addreses;
3889 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3890 					sm_key_t peer_irk;
3891 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3892 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3893 
3894 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
3895 					// trigger whitelist entry 'update' (work around for controller bug)
3896 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3897 					while (btstack_linked_list_iterator_has_next(&lit)) {
3898 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
3899 						if (entry->address_type != peer_identity_addr_type) continue;
3900 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
3901 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
3902 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
3903 					}
3904 #endif
3905 
3906 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
3907 								 peer_identity_addreses);
3908 					return true;
3909 				}
3910 
3911 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
3912 
3913 				/* fall through */
3914 
3915 			case LE_RESOLVING_LIST_ADD_ENTRIES:
3916 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3917 					uint8_t offset = i >> 3;
3918 					uint8_t mask = 1 << (i & 7);
3919 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
3920 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
3921 					bd_addr_t peer_identity_addreses;
3922 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3923 					sm_key_t peer_irk;
3924 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3925 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3926 					const uint8_t *local_irk = gap_get_persistent_irk();
3927 					// command uses format specifier 'P' that stores 16-byte value without flip
3928 					uint8_t local_irk_flipped[16];
3929 					uint8_t peer_irk_flipped[16];
3930 					reverse_128(local_irk, local_irk_flipped);
3931 					reverse_128(peer_irk, peer_irk_flipped);
3932 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
3933 								 peer_irk_flipped, local_irk_flipped);
3934 					return true;
3935 				}
3936 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3937 				break;
3938 
3939 			default:
3940 				break;
3941 		}
3942 	}
3943     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3944 #endif
3945 
3946     // Phase 4: restore state
3947 
3948 #ifdef ENABLE_LE_CENTRAL
3949     // re-start scanning
3950     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3951         hci_stack->le_scanning_active = true;
3952         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3953         return true;
3954     }
3955 #endif
3956 
3957 #ifdef ENABLE_LE_CENTRAL
3958     // re-start connecting
3959     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3960         bd_addr_t null_addr;
3961         memset(null_addr, 0, 6);
3962         hci_send_cmd(&hci_le_create_connection,
3963                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3964                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3965                      1,         // use whitelist
3966                      0,         // peer address type
3967                      null_addr, // peer bd addr
3968                      hci_stack->le_own_addr_type, // our addr type:
3969                      hci_stack->le_connection_interval_min,    // conn interval min
3970                      hci_stack->le_connection_interval_max,    // conn interval max
3971                      hci_stack->le_connection_latency,         // conn latency
3972                      hci_stack->le_supervision_timeout,        // conn latency
3973                      hci_stack->le_minimum_ce_length,          // min ce length
3974                      hci_stack->le_maximum_ce_length           // max ce length
3975         );
3976         return true;
3977     }
3978 #endif
3979 
3980 #ifdef ENABLE_LE_PERIPHERAL
3981     // re-start advertising
3982     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
3983         // check if advertisements should be enabled given
3984         hci_stack->le_advertisements_active = true;
3985         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3986         return true;
3987     }
3988 #endif
3989 
3990     return false;
3991 }
3992 #endif
3993 
3994 static bool hci_run_general_pending_commands(void){
3995     btstack_linked_item_t * it;
3996     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3997         hci_connection_t * connection = (hci_connection_t *) it;
3998 
3999         switch(connection->state){
4000             case SEND_CREATE_CONNECTION:
4001                 switch(connection->address_type){
4002 #ifdef ENABLE_CLASSIC
4003                     case BD_ADDR_TYPE_ACL:
4004                         log_info("sending hci_create_connection");
4005                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4006                         break;
4007 #endif
4008                     default:
4009 #ifdef ENABLE_BLE
4010 #ifdef ENABLE_LE_CENTRAL
4011                         log_info("sending hci_le_create_connection");
4012                         hci_send_cmd(&hci_le_create_connection,
4013                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4014                                      hci_stack->le_connection_scan_window,      // conn scan windows
4015                                      0,         // don't use whitelist
4016                                      connection->address_type, // peer address type
4017                                      connection->address,      // peer bd addr
4018                                      hci_stack->le_own_addr_type, // our addr type:
4019                                      hci_stack->le_connection_interval_min,    // conn interval min
4020                                      hci_stack->le_connection_interval_max,    // conn interval max
4021                                      hci_stack->le_connection_latency,         // conn latency
4022                                      hci_stack->le_supervision_timeout,        // conn latency
4023                                      hci_stack->le_minimum_ce_length,          // min ce length
4024                                      hci_stack->le_maximum_ce_length          // max ce length
4025                         );
4026                         connection->state = SENT_CREATE_CONNECTION;
4027 #endif
4028 #endif
4029                         break;
4030                 }
4031                 return true;
4032 
4033 #ifdef ENABLE_CLASSIC
4034             case RECEIVED_CONNECTION_REQUEST:
4035                 connection->role  = HCI_ROLE_SLAVE;
4036                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4037                     log_info("sending hci_accept_connection_request");
4038                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4039                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4040                 }
4041                 return true;
4042 #endif
4043 
4044 #ifdef ENABLE_BLE
4045 #ifdef ENABLE_LE_CENTRAL
4046             case SEND_CANCEL_CONNECTION:
4047                 connection->state = SENT_CANCEL_CONNECTION;
4048                 hci_send_cmd(&hci_le_create_connection_cancel);
4049                 return true;
4050 #endif
4051 #endif
4052             case SEND_DISCONNECT:
4053                 connection->state = SENT_DISCONNECT;
4054                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4055                 return true;
4056 
4057             default:
4058                 break;
4059         }
4060 
4061         // no further commands if connection is about to get shut down
4062         if (connection->state == SENT_DISCONNECT) continue;
4063 
4064         if (connection->authentication_flags & READ_RSSI){
4065             connectionClearAuthenticationFlags(connection, READ_RSSI);
4066             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4067             return true;
4068         }
4069 
4070 #ifdef ENABLE_CLASSIC
4071 
4072         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4073             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4074             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4075             return true;
4076         }
4077 
4078         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
4079             log_info("responding to link key request");
4080             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4081 
4082             link_key_t link_key;
4083             link_key_type_t link_key_type;
4084             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
4085 
4086             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4087             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4088             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
4089             if (sc_downgrade){
4090                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4091                 connection->state = SENT_DISCONNECT;
4092                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4093                 return true;
4094             }
4095 
4096             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
4097             if (have_link_key && security_level_sufficient){
4098                 connection->link_key_type = link_key_type;
4099                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
4100             } else {
4101                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4102             }
4103             return true;
4104         }
4105 
4106         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4107             log_info("denying to pin request");
4108             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4109             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4110             return true;
4111         }
4112 
4113         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4114             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4115             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
4116             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
4117                 // tweak authentication requirements
4118                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
4119                 if (connection->bonding_flags & BONDING_DEDICATED){
4120                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4121                 }
4122                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4123                     authreq |= 1;
4124                 }
4125                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
4126             } else {
4127                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4128             }
4129             return true;
4130         }
4131 
4132         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4133             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4134             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4135             return true;
4136         }
4137 
4138         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4139             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4140             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4141             return true;
4142         }
4143 
4144         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4145             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4146             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4147             return true;
4148         }
4149 
4150         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4151             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4152             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4153             return true;
4154         }
4155 
4156         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4157             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4158             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4159             return true;
4160         }
4161 
4162         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4163             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4164             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4165             connection->state = SENT_DISCONNECT;
4166             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4167             return true;
4168         }
4169 
4170         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4171             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4172             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4173             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4174             return true;
4175         }
4176 
4177         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4178             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4179             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4180             return true;
4181         }
4182         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4183             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4184             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4185             return true;
4186         }
4187 #endif
4188 
4189         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4190             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4191             if (connection->state != SENT_DISCONNECT){
4192                 connection->state = SENT_DISCONNECT;
4193                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4194                 return true;
4195             }
4196         }
4197 
4198 #ifdef ENABLE_CLASSIC
4199         uint16_t sniff_min_interval;
4200         switch (connection->sniff_min_interval){
4201             case 0:
4202                 break;
4203             case 0xffff:
4204                 connection->sniff_min_interval = 0;
4205                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4206                 return true;
4207             default:
4208                 sniff_min_interval = connection->sniff_min_interval;
4209                 connection->sniff_min_interval = 0;
4210                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4211                 return true;
4212         }
4213 
4214         if (connection->request_role != HCI_ROLE_INVALID){
4215             hci_role_t  role = connection->request_role;
4216             connection->request_role = HCI_ROLE_INVALID;
4217             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4218             return true;
4219         }
4220 #endif
4221 
4222 #ifdef ENABLE_BLE
4223         switch (connection->le_con_parameter_update_state){
4224             // response to L2CAP CON PARAMETER UPDATE REQUEST
4225             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4226                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4227                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4228                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4229                              0x0000, 0xffff);
4230                 return true;
4231             case CON_PARAMETER_UPDATE_REPLY:
4232                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4233                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4234                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4235                              0x0000, 0xffff);
4236                 return true;
4237             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4238                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4239                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4240                 return true;
4241             default:
4242                 break;
4243         }
4244         if (connection->le_phy_update_all_phys != 0xffu){
4245             uint8_t all_phys = connection->le_phy_update_all_phys;
4246             connection->le_phy_update_all_phys = 0xff;
4247             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);
4248             return true;
4249         }
4250 #endif
4251     }
4252     return false;
4253 }
4254 
4255 static void hci_run(void){
4256 
4257     bool done;
4258 
4259     // send continuation fragments first, as they block the prepared packet buffer
4260     done = hci_run_acl_fragments();
4261     if (done) return;
4262 
4263 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4264     // send host num completed packets next as they don't require num_cmd_packets > 0
4265     if (!hci_can_send_comand_packet_transport()) return;
4266     if (hci_stack->host_completed_packets){
4267         hci_host_num_completed_packets();
4268         return;
4269     }
4270 #endif
4271 
4272     if (!hci_can_send_command_packet_now()) return;
4273 
4274     // global/non-connection oriented commands
4275 
4276 
4277 #ifdef ENABLE_CLASSIC
4278     // general gap classic
4279     done = hci_run_general_gap_classic();
4280     if (done) return;
4281 #endif
4282 
4283 #ifdef ENABLE_BLE
4284     // general gap le
4285     done = hci_run_general_gap_le();
4286     if (done) return;
4287 #endif
4288 
4289     // send pending HCI commands
4290     done = hci_run_general_pending_commands();
4291     if (done) return;
4292 
4293     // stack state sub statemachines
4294     hci_connection_t * connection;
4295     switch (hci_stack->state){
4296         case HCI_STATE_INITIALIZING:
4297             hci_initializing_run();
4298             break;
4299 
4300         case HCI_STATE_HALTING:
4301 
4302             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4303             switch (hci_stack->substate){
4304                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4305                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4306 
4307 #ifdef ENABLE_BLE
4308 #ifdef ENABLE_LE_CENTRAL
4309                     // free whitelist entries
4310                     {
4311                         btstack_linked_list_iterator_t lit;
4312                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4313                         while (btstack_linked_list_iterator_has_next(&lit)){
4314                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4315                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4316                             btstack_memory_whitelist_entry_free(entry);
4317                         }
4318                     }
4319 #endif
4320 #endif
4321                     // close all open connections
4322                     connection =  (hci_connection_t *) hci_stack->connections;
4323                     if (connection){
4324                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4325                         if (!hci_can_send_command_packet_now()) return;
4326 
4327                         // check state
4328                         if (connection->state == SENT_DISCONNECT) return;
4329                         connection->state = SENT_DISCONNECT;
4330 
4331                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4332 
4333                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4334                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4335 
4336                         // ... which would be ignored anyway as we shutdown (free) the connection now
4337                         hci_shutdown_connection(connection);
4338 
4339                         // finally, send the disconnect command
4340                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4341                         return;
4342                     }
4343 
4344                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4345                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4346                         log_info("HCI_STATE_HALTING: wait 50 ms");
4347                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4348                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4349                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4350                         btstack_run_loop_add_timer(&hci_stack->timeout);
4351                         break;
4352                     }
4353 
4354                     /* fall through */
4355 
4356                 case HCI_HALTING_CLOSE:
4357                     log_info("HCI_STATE_HALTING, calling off");
4358 
4359                     // switch mode
4360                     hci_power_control_off();
4361 
4362                     log_info("HCI_STATE_HALTING, emitting state");
4363                     hci_emit_state();
4364                     log_info("HCI_STATE_HALTING, done");
4365                     break;
4366 
4367                 case HCI_HALTING_W4_TIMER:
4368                     // keep waiting
4369 
4370                     break;
4371                 default:
4372                     break;
4373             }
4374 
4375             break;
4376 
4377         case HCI_STATE_FALLING_ASLEEP:
4378             switch(hci_stack->substate) {
4379                 case HCI_FALLING_ASLEEP_DISCONNECT:
4380                     log_info("HCI_STATE_FALLING_ASLEEP");
4381                     // close all open connections
4382                     connection =  (hci_connection_t *) hci_stack->connections;
4383 
4384 #ifdef HAVE_PLATFORM_IPHONE_OS
4385                     // don't close connections, if H4 supports power management
4386                     if (btstack_control_iphone_power_management_enabled()){
4387                         connection = NULL;
4388                     }
4389 #endif
4390                     if (connection){
4391 
4392                         // send disconnect
4393                         if (!hci_can_send_command_packet_now()) return;
4394 
4395                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4396                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4397 
4398                         // send disconnected event right away - causes higher layer connections to get closed, too.
4399                         hci_shutdown_connection(connection);
4400                         return;
4401                     }
4402 
4403                     if (hci_classic_supported()){
4404                         // disable page and inquiry scan
4405                         if (!hci_can_send_command_packet_now()) return;
4406 
4407                         log_info("HCI_STATE_HALTING, disabling inq scans");
4408                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4409 
4410                         // continue in next sub state
4411                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4412                         break;
4413                     }
4414 
4415                     /* fall through */
4416 
4417                 case HCI_FALLING_ASLEEP_COMPLETE:
4418                     log_info("HCI_STATE_HALTING, calling sleep");
4419 #ifdef HAVE_PLATFORM_IPHONE_OS
4420                     // don't actually go to sleep, if H4 supports power management
4421                     if (btstack_control_iphone_power_management_enabled()){
4422                         // SLEEP MODE reached
4423                         hci_stack->state = HCI_STATE_SLEEPING;
4424                         hci_emit_state();
4425                         break;
4426                     }
4427 #endif
4428                     // switch mode
4429                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4430                     hci_emit_state();
4431                     break;
4432 
4433                 default:
4434                     break;
4435             }
4436             break;
4437 
4438         default:
4439             break;
4440     }
4441 }
4442 
4443 int hci_send_cmd_packet(uint8_t *packet, int size){
4444     // house-keeping
4445 
4446 #ifdef ENABLE_CLASSIC
4447     bd_addr_t addr;
4448     hci_connection_t * conn;
4449 #endif
4450 #ifdef ENABLE_LE_CENTRAL
4451     uint8_t initiator_filter_policy;
4452 #endif
4453 
4454     uint16_t opcode = little_endian_read_16(packet, 0);
4455     switch (opcode) {
4456         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4457             hci_stack->loopback_mode = packet[3];
4458             break;
4459 
4460 #ifdef ENABLE_CLASSIC
4461         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4462             reverse_bd_addr(&packet[3], addr);
4463             log_info("Create_connection to %s", bd_addr_to_str(addr));
4464 
4465             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4466             if (!conn) {
4467                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4468                 if (!conn) {
4469                     // notify client that alloc failed
4470                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4471                     return -1; // packet not sent to controller
4472                 }
4473                 conn->state = SEND_CREATE_CONNECTION;
4474                 conn->role  = HCI_ROLE_MASTER;
4475             }
4476             log_info("conn state %u", conn->state);
4477             switch (conn->state) {
4478                 // if connection active exists
4479                 case OPEN:
4480                     // and OPEN, emit connection complete command
4481                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4482                     return -1; // packet not sent to controller
4483                 case RECEIVED_DISCONNECTION_COMPLETE:
4484                     // create connection triggered in disconnect complete event, let's do it now
4485                     break;
4486                 case SEND_CREATE_CONNECTION:
4487                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4488                     break;
4489                 default:
4490                     // otherwise, just ignore as it is already in the open process
4491                     return -1; // packet not sent to controller
4492             }
4493             conn->state = SENT_CREATE_CONNECTION;
4494 
4495             // track outgoing connection
4496             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4497             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4498             break;
4499         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4500             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4501             break;
4502         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4503             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4504             break;
4505         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4506             if (hci_stack->link_key_db) {
4507                 reverse_bd_addr(&packet[3], addr);
4508                 hci_stack->link_key_db->delete_link_key(addr);
4509             }
4510             break;
4511         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4512         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4513             reverse_bd_addr(&packet[3], addr);
4514             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4515             if (conn) {
4516                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4517             }
4518             break;
4519         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4520         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4521         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4522         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4523             reverse_bd_addr(&packet[3], addr);
4524             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4525             if (conn) {
4526                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4527             }
4528             break;
4529 
4530 #ifdef ENABLE_SCO_OVER_HCI
4531         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4532             // setup_synchronous_connection? Voice setting at offset 22
4533             // TODO: compare to current setting if sco connection already active
4534             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4535             break;
4536         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4537             // accept_synchronus_connection? Voice setting at offset 18
4538             // TODO: compare to current setting if sco connection already active
4539             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4540             break;
4541 #endif
4542 #endif
4543 
4544 #ifdef ENABLE_BLE
4545         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4546             hci_stack->le_random_address_set = 1;
4547             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4548             break;
4549 #ifdef ENABLE_LE_PERIPHERAL
4550         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4551             hci_stack->le_advertisements_active = packet[3] != 0;
4552             break;
4553 #endif
4554 #ifdef ENABLE_LE_CENTRAL
4555         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4556             // white list used?
4557             initiator_filter_policy = packet[7];
4558             switch (initiator_filter_policy) {
4559                 case 0:
4560                     // whitelist not used
4561                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4562                     break;
4563                 case 1:
4564                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4565                     break;
4566                 default:
4567                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4568                     break;
4569             }
4570             // track outgoing connection
4571             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4572             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4573             break;
4574         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4575             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4576             break;
4577 #endif
4578 #endif
4579         default:
4580             break;
4581     }
4582 
4583     hci_stack->num_cmd_packets--;
4584 
4585     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4586     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4587 }
4588 
4589 // disconnect because of security block
4590 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4591     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4592     if (!connection) return;
4593     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4594 }
4595 
4596 
4597 // Configure Secure Simple Pairing
4598 
4599 #ifdef ENABLE_CLASSIC
4600 
4601 // enable will enable SSP during init
4602 void gap_ssp_set_enable(int enable){
4603     hci_stack->ssp_enable = enable;
4604 }
4605 
4606 static int hci_local_ssp_activated(void){
4607     return gap_ssp_supported() && hci_stack->ssp_enable;
4608 }
4609 
4610 // if set, BTstack will respond to io capability request using authentication requirement
4611 void gap_ssp_set_io_capability(int io_capability){
4612     hci_stack->ssp_io_capability = io_capability;
4613 }
4614 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4615     hci_stack->ssp_authentication_requirement = authentication_requirement;
4616 }
4617 
4618 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4619 void gap_ssp_set_auto_accept(int auto_accept){
4620     hci_stack->ssp_auto_accept = auto_accept;
4621 }
4622 
4623 void gap_secure_connections_enable(bool enable){
4624     hci_stack->secure_connections_enable = enable;
4625 }
4626 
4627 #endif
4628 
4629 // va_list part of hci_send_cmd
4630 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4631     if (!hci_can_send_command_packet_now()){
4632         log_error("hci_send_cmd called but cannot send packet now");
4633         return 0;
4634     }
4635 
4636     // for HCI INITIALIZATION
4637     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4638     hci_stack->last_cmd_opcode = cmd->opcode;
4639 
4640     hci_reserve_packet_buffer();
4641     uint8_t * packet = hci_stack->hci_packet_buffer;
4642     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4643     int err = hci_send_cmd_packet(packet, size);
4644 
4645     // release packet buffer on error or for synchronous transport implementations
4646     if ((err < 0) || hci_transport_synchronous()){
4647         hci_release_packet_buffer();
4648         hci_emit_transport_packet_sent();
4649     }
4650 
4651     return err;
4652 }
4653 
4654 /**
4655  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4656  */
4657 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4658     va_list argptr;
4659     va_start(argptr, cmd);
4660     int res = hci_send_cmd_va_arg(cmd, argptr);
4661     va_end(argptr);
4662     return res;
4663 }
4664 
4665 // Create various non-HCI events.
4666 // TODO: generalize, use table similar to hci_create_command
4667 
4668 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4669     // dump packet
4670     if (dump) {
4671         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4672     }
4673 
4674     // dispatch to all event handlers
4675     btstack_linked_list_iterator_t it;
4676     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4677     while (btstack_linked_list_iterator_has_next(&it)){
4678         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4679         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4680     }
4681 }
4682 
4683 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4684     if (!hci_stack->acl_packet_handler) return;
4685     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4686 }
4687 
4688 #ifdef ENABLE_CLASSIC
4689 static void hci_notify_if_sco_can_send_now(void){
4690     // notify SCO sender if waiting
4691     if (!hci_stack->sco_waiting_for_can_send_now) return;
4692     if (hci_can_send_sco_packet_now()){
4693         hci_stack->sco_waiting_for_can_send_now = 0;
4694         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4695         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4696         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4697     }
4698 }
4699 
4700 // parsing end emitting has been merged to reduce code size
4701 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4702     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4703 
4704     uint8_t * eir_data;
4705     ad_context_t context;
4706     const uint8_t * name;
4707     uint8_t         name_len;
4708 
4709     if (size < 3) return;
4710 
4711     int event_type = hci_event_packet_get_type(packet);
4712     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4713     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4714 
4715     switch (event_type){
4716         case HCI_EVENT_INQUIRY_RESULT:
4717         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4718             if (size != (3 + (num_responses * 14))) return;
4719             break;
4720         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4721             if (size != 257) return;
4722             if (num_responses != 1) return;
4723             break;
4724         default:
4725             return;
4726     }
4727 
4728     // event[1] is set at the end
4729     int i;
4730     for (i=0; i<num_responses;i++){
4731         memset(event, 0, sizeof(event));
4732         event[0] = GAP_EVENT_INQUIRY_RESULT;
4733         uint8_t event_size = 18;    // if name is not set by EIR
4734 
4735         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4736         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4737         (void)memcpy(&event[9],
4738                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4739                      3); // class of device
4740         (void)memcpy(&event[12],
4741                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4742                      2); // clock offset
4743 
4744         switch (event_type){
4745             case HCI_EVENT_INQUIRY_RESULT:
4746                 // 14,15,16,17 = 0, size 18
4747                 break;
4748             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4749                 event[14] = 1;
4750                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4751                 // 16,17 = 0, size 18
4752                 break;
4753             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4754                 event[14] = 1;
4755                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4756                 // EIR packets only contain a single inquiry response
4757                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4758                 name = NULL;
4759                 // Iterate over EIR data
4760                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4761                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4762                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4763                     const uint8_t * data = ad_iterator_get_data(&context);
4764                     // Prefer Complete Local Name over Shortend Local Name
4765                     switch (data_type){
4766                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4767                             if (name) continue;
4768                             /* fall through */
4769                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4770                             name = data;
4771                             name_len = data_size;
4772                             break;
4773                         default:
4774                             break;
4775                     }
4776                 }
4777                 if (name){
4778                     event[16] = 1;
4779                     // truncate name if needed
4780                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4781                     event[17] = len;
4782                     (void)memcpy(&event[18], name, len);
4783                     event_size += len;
4784                 }
4785                 break;
4786             default:
4787                 return;
4788         }
4789         event[1] = event_size - 2;
4790         hci_emit_event(event, event_size, 1);
4791     }
4792 }
4793 #endif
4794 
4795 void hci_emit_state(void){
4796     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4797     uint8_t event[3];
4798     event[0] = BTSTACK_EVENT_STATE;
4799     event[1] = sizeof(event) - 2u;
4800     event[2] = hci_stack->state;
4801     hci_emit_event(event, sizeof(event), 1);
4802 }
4803 
4804 #ifdef ENABLE_CLASSIC
4805 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4806     uint8_t event[13];
4807     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4808     event[1] = sizeof(event) - 2;
4809     event[2] = status;
4810     little_endian_store_16(event, 3, con_handle);
4811     reverse_bd_addr(address, &event[5]);
4812     event[11] = 1; // ACL connection
4813     event[12] = 0; // encryption disabled
4814     hci_emit_event(event, sizeof(event), 1);
4815 }
4816 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4817     if (disable_l2cap_timeouts) return;
4818     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4819     uint8_t event[4];
4820     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4821     event[1] = sizeof(event) - 2;
4822     little_endian_store_16(event, 2, conn->con_handle);
4823     hci_emit_event(event, sizeof(event), 1);
4824 }
4825 #endif
4826 
4827 #ifdef ENABLE_BLE
4828 #ifdef ENABLE_LE_CENTRAL
4829 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){
4830     uint8_t event[21];
4831     event[0] = HCI_EVENT_LE_META;
4832     event[1] = sizeof(event) - 2u;
4833     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4834     event[3] = status;
4835     little_endian_store_16(event, 4, con_handle);
4836     event[6] = 0; // TODO: role
4837     event[7] = address_type;
4838     reverse_bd_addr(address, &event[8]);
4839     little_endian_store_16(event, 14, 0); // interval
4840     little_endian_store_16(event, 16, 0); // latency
4841     little_endian_store_16(event, 18, 0); // supervision timeout
4842     event[20] = 0; // master clock accuracy
4843     hci_emit_event(event, sizeof(event), 1);
4844 }
4845 #endif
4846 #endif
4847 
4848 static void hci_emit_transport_packet_sent(void){
4849     // notify upper stack that it might be possible to send again
4850     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4851     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4852 }
4853 
4854 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4855     uint8_t event[6];
4856     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4857     event[1] = sizeof(event) - 2u;
4858     event[2] = 0; // status = OK
4859     little_endian_store_16(event, 3, con_handle);
4860     event[5] = reason;
4861     hci_emit_event(event, sizeof(event), 1);
4862 }
4863 
4864 static void hci_emit_nr_connections_changed(void){
4865     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4866     uint8_t event[3];
4867     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4868     event[1] = sizeof(event) - 2u;
4869     event[2] = nr_hci_connections();
4870     hci_emit_event(event, sizeof(event), 1);
4871 }
4872 
4873 static void hci_emit_hci_open_failed(void){
4874     log_info("BTSTACK_EVENT_POWERON_FAILED");
4875     uint8_t event[2];
4876     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4877     event[1] = sizeof(event) - 2u;
4878     hci_emit_event(event, sizeof(event), 1);
4879 }
4880 
4881 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4882     log_info("hci_emit_dedicated_bonding_result %u ", status);
4883     uint8_t event[9];
4884     int pos = 0;
4885     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4886     event[pos++] = sizeof(event) - 2u;
4887     event[pos++] = status;
4888     reverse_bd_addr(address, &event[pos]);
4889     hci_emit_event(event, sizeof(event), 1);
4890 }
4891 
4892 
4893 #ifdef ENABLE_CLASSIC
4894 
4895 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4896     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4897     uint8_t event[5];
4898     int pos = 0;
4899     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4900     event[pos++] = sizeof(event) - 2;
4901     little_endian_store_16(event, 2, con_handle);
4902     pos += 2;
4903     event[pos++] = level;
4904     hci_emit_event(event, sizeof(event), 1);
4905 }
4906 
4907 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4908     if (!connection) return LEVEL_0;
4909     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4910     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4911     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4912     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4913     // LEVEL 4 always requires 128 bit encrytion key size
4914     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4915         security_level = LEVEL_3;
4916     }
4917     return security_level;
4918 }
4919 
4920 static void hci_emit_discoverable_enabled(uint8_t enabled){
4921     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4922     uint8_t event[3];
4923     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4924     event[1] = sizeof(event) - 2;
4925     event[2] = enabled;
4926     hci_emit_event(event, sizeof(event), 1);
4927 }
4928 
4929 // query if remote side supports eSCO
4930 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4931     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4932     if (!connection) return 0;
4933     return (connection->remote_supported_features[0] & 1) != 0;
4934 }
4935 
4936 static bool hci_ssp_supported(hci_connection_t * connection){
4937     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4938     return (connection->bonding_flags & mask) == mask;
4939 }
4940 
4941 // query if remote side supports SSP
4942 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4943     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4944     if (!connection) return 0;
4945     return hci_ssp_supported(connection) ? 1 : 0;
4946 }
4947 
4948 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4949     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4950 }
4951 
4952 // GAP API
4953 /**
4954  * @bbrief enable/disable bonding. default is enabled
4955  * @praram enabled
4956  */
4957 void gap_set_bondable_mode(int enable){
4958     hci_stack->bondable = enable ? 1 : 0;
4959 }
4960 /**
4961  * @brief Get bondable mode.
4962  * @return 1 if bondable
4963  */
4964 int gap_get_bondable_mode(void){
4965     return hci_stack->bondable;
4966 }
4967 
4968 /**
4969  * @brief map link keys to security levels
4970  */
4971 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4972     switch (link_key_type){
4973         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4974             return LEVEL_4;
4975         case COMBINATION_KEY:
4976         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4977             return LEVEL_3;
4978         default:
4979             return LEVEL_2;
4980     }
4981 }
4982 
4983 /**
4984  * @brief map link keys to secure connection yes/no
4985  */
4986 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4987     switch (link_key_type){
4988         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4989         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4990             return 1;
4991         default:
4992             return 0;
4993     }
4994 }
4995 
4996 /**
4997  * @brief map link keys to authenticated
4998  */
4999 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5000     switch (link_key_type){
5001         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5002         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5003             return 1;
5004         default:
5005             return 0;
5006     }
5007 }
5008 
5009 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5010     log_info("gap_mitm_protection_required_for_security_level %u", level);
5011     return level > LEVEL_2;
5012 }
5013 
5014 /**
5015  * @brief get current security level
5016  */
5017 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5018     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5019     if (!connection) return LEVEL_0;
5020     return gap_security_level_for_connection(connection);
5021 }
5022 
5023 /**
5024  * @brief request connection to device to
5025  * @result GAP_AUTHENTICATION_RESULT
5026  */
5027 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5028     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5029     if (!connection){
5030         hci_emit_security_level(con_handle, LEVEL_0);
5031         return;
5032     }
5033     gap_security_level_t current_level = gap_security_level(con_handle);
5034     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5035         requested_level, connection->requested_security_level, current_level);
5036 
5037     // assumption: earlier requested security higher than current level => security request is active
5038     if (current_level < connection->requested_security_level){
5039         if (connection->requested_security_level < requested_level){
5040             // increase requested level as new level is higher
5041 
5042             // TODO: handle re-authentication when done
5043 
5044             connection->requested_security_level = requested_level;
5045         }
5046         return;
5047     }
5048 
5049     // no request active, notify if security sufficient
5050     if (requested_level <= current_level){
5051         hci_emit_security_level(con_handle, current_level);
5052         return;
5053     }
5054 
5055     // start pairing to increase security level
5056     connection->requested_security_level = requested_level;
5057 
5058 #if 0
5059     // sending encryption request without a link key results in an error.
5060     // TODO: figure out how to use it properly
5061 
5062     // would enabling ecnryption suffice (>= LEVEL_2)?
5063     if (hci_stack->link_key_db){
5064         link_key_type_t link_key_type;
5065         link_key_t      link_key;
5066         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
5067             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
5068                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
5069                 return;
5070             }
5071         }
5072     }
5073 #endif
5074 
5075     // start to authenticate connection if not already active
5076     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
5077     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5078     hci_run();
5079 }
5080 
5081 /**
5082  * @brief start dedicated bonding with device. disconnect after bonding
5083  * @param device
5084  * @param request MITM protection
5085  * @result GAP_DEDICATED_BONDING_COMPLETE
5086  */
5087 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5088 
5089     // create connection state machine
5090     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5091 
5092     if (!connection){
5093         return BTSTACK_MEMORY_ALLOC_FAILED;
5094     }
5095 
5096     // delete linkn key
5097     gap_drop_link_key_for_bd_addr(device);
5098 
5099     // configure LEVEL_2/3, dedicated bonding
5100     connection->state = SEND_CREATE_CONNECTION;
5101     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5102     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5103     connection->bonding_flags = BONDING_DEDICATED;
5104 
5105     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5106 
5107     // handle: connnection failure (connection complete != ok)
5108     // handle: authentication failure
5109     // handle: disconnect on done
5110 
5111     hci_run();
5112 
5113     return 0;
5114 }
5115 #endif
5116 
5117 void gap_set_local_name(const char * local_name){
5118     hci_stack->local_name = local_name;
5119 }
5120 
5121 
5122 #ifdef ENABLE_BLE
5123 
5124 #ifdef ENABLE_LE_CENTRAL
5125 void gap_start_scan(void){
5126     hci_stack->le_scanning_enabled = true;
5127     hci_run();
5128 }
5129 
5130 void gap_stop_scan(void){
5131     hci_stack->le_scanning_enabled = false;
5132     hci_run();
5133 }
5134 
5135 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5136     hci_stack->le_scan_type          = scan_type;
5137     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5138     hci_stack->le_scan_interval      = scan_interval;
5139     hci_stack->le_scan_window        = scan_window;
5140     hci_stack->le_scanning_param_update = true;
5141     hci_run();
5142 }
5143 
5144 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5145     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5146 }
5147 
5148 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5149     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5150     if (!conn){
5151         // disallow if le connection is already outgoing
5152         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5153             log_error("le connection already active");
5154             return ERROR_CODE_COMMAND_DISALLOWED;
5155         }
5156 
5157         log_info("gap_connect: no connection exists yet, creating context");
5158         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5159         if (!conn){
5160             // notify client that alloc failed
5161             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5162             log_info("gap_connect: failed to alloc hci_connection_t");
5163             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5164         }
5165 
5166         // set le connecting state
5167         if (hci_is_le_connection_type(addr_type)){
5168             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5169         }
5170 
5171         conn->state = SEND_CREATE_CONNECTION;
5172         log_info("gap_connect: send create connection next");
5173         hci_run();
5174         return ERROR_CODE_SUCCESS;
5175     }
5176 
5177     if (!hci_is_le_connection(conn) ||
5178         (conn->state == SEND_CREATE_CONNECTION) ||
5179         (conn->state == SENT_CREATE_CONNECTION)) {
5180         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5181         log_error("gap_connect: classic connection or connect is already being created");
5182         return GATT_CLIENT_IN_WRONG_STATE;
5183     }
5184 
5185     // check if connection was just disconnected
5186     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5187         log_info("gap_connect: send create connection (again)");
5188         conn->state = SEND_CREATE_CONNECTION;
5189         hci_run();
5190         return ERROR_CODE_SUCCESS;
5191     }
5192 
5193     log_info("gap_connect: context exists with state %u", conn->state);
5194     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5195     hci_run();
5196     return ERROR_CODE_SUCCESS;
5197 }
5198 
5199 // @assumption: only a single outgoing LE Connection exists
5200 static hci_connection_t * gap_get_outgoing_connection(void){
5201     btstack_linked_item_t *it;
5202     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5203         hci_connection_t * conn = (hci_connection_t *) it;
5204         if (!hci_is_le_connection(conn)) continue;
5205         switch (conn->state){
5206             case SEND_CREATE_CONNECTION:
5207             case SENT_CREATE_CONNECTION:
5208             case SENT_CANCEL_CONNECTION:
5209                 return conn;
5210             default:
5211                 break;
5212         };
5213     }
5214     return NULL;
5215 }
5216 
5217 uint8_t gap_connect_cancel(void){
5218     hci_connection_t * conn = gap_get_outgoing_connection();
5219     if (!conn) return 0;
5220     switch (conn->state){
5221         case SEND_CREATE_CONNECTION:
5222             // skip sending create connection and emit event instead
5223             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5224             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5225             btstack_memory_hci_connection_free( conn );
5226             break;
5227         case SENT_CREATE_CONNECTION:
5228             // request to send cancel connection
5229             conn->state = SEND_CANCEL_CONNECTION;
5230             hci_run();
5231             break;
5232         default:
5233             break;
5234     }
5235     return 0;
5236 }
5237 #endif
5238 
5239 #ifdef ENABLE_LE_CENTRAL
5240 /**
5241  * @brief Set connection parameters for outgoing connections
5242  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5243  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5244  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5245  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5246  * @param conn_latency, default: 4
5247  * @param supervision_timeout (unit: 10ms), default: 720 ms
5248  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5249  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5250  */
5251 
5252 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5253     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5254     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5255     hci_stack->le_connection_scan_interval = conn_scan_interval;
5256     hci_stack->le_connection_scan_window = conn_scan_window;
5257     hci_stack->le_connection_interval_min = conn_interval_min;
5258     hci_stack->le_connection_interval_max = conn_interval_max;
5259     hci_stack->le_connection_latency = conn_latency;
5260     hci_stack->le_supervision_timeout = supervision_timeout;
5261     hci_stack->le_minimum_ce_length = min_ce_length;
5262     hci_stack->le_maximum_ce_length = max_ce_length;
5263 }
5264 #endif
5265 
5266 /**
5267  * @brief Updates the connection parameters for a given LE connection
5268  * @param handle
5269  * @param conn_interval_min (unit: 1.25ms)
5270  * @param conn_interval_max (unit: 1.25ms)
5271  * @param conn_latency
5272  * @param supervision_timeout (unit: 10ms)
5273  * @returns 0 if ok
5274  */
5275 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5276     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5277     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5278     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5279     connection->le_conn_interval_min = conn_interval_min;
5280     connection->le_conn_interval_max = conn_interval_max;
5281     connection->le_conn_latency = conn_latency;
5282     connection->le_supervision_timeout = supervision_timeout;
5283     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5284     hci_run();
5285     return 0;
5286 }
5287 
5288 /**
5289  * @brief Request an update of the connection parameter for a given LE connection
5290  * @param handle
5291  * @param conn_interval_min (unit: 1.25ms)
5292  * @param conn_interval_max (unit: 1.25ms)
5293  * @param conn_latency
5294  * @param supervision_timeout (unit: 10ms)
5295  * @returns 0 if ok
5296  */
5297 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5298     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5299     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5300     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5301     connection->le_conn_interval_min = conn_interval_min;
5302     connection->le_conn_interval_max = conn_interval_max;
5303     connection->le_conn_latency = conn_latency;
5304     connection->le_supervision_timeout = supervision_timeout;
5305     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5306     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5307     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5308     return 0;
5309 }
5310 
5311 #ifdef ENABLE_LE_PERIPHERAL
5312 
5313 /**
5314  * @brief Set Advertisement Data
5315  * @param advertising_data_length
5316  * @param advertising_data (max 31 octets)
5317  * @note data is not copied, pointer has to stay valid
5318  */
5319 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5320     hci_stack->le_advertisements_data_len = advertising_data_length;
5321     hci_stack->le_advertisements_data = advertising_data;
5322     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5323     hci_run();
5324 }
5325 
5326 /**
5327  * @brief Set Scan Response Data
5328  * @param advertising_data_length
5329  * @param advertising_data (max 31 octets)
5330  * @note data is not copied, pointer has to stay valid
5331  */
5332 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5333     hci_stack->le_scan_response_data_len = scan_response_data_length;
5334     hci_stack->le_scan_response_data = scan_response_data;
5335     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5336     hci_run();
5337 }
5338 
5339 /**
5340  * @brief Set Advertisement Parameters
5341  * @param adv_int_min
5342  * @param adv_int_max
5343  * @param adv_type
5344  * @param direct_address_type
5345  * @param direct_address
5346  * @param channel_map
5347  * @param filter_policy
5348  *
5349  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5350  */
5351  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5352     uint8_t direct_address_typ, bd_addr_t direct_address,
5353     uint8_t channel_map, uint8_t filter_policy) {
5354 
5355     hci_stack->le_advertisements_interval_min = adv_int_min;
5356     hci_stack->le_advertisements_interval_max = adv_int_max;
5357     hci_stack->le_advertisements_type = adv_type;
5358     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5359     hci_stack->le_advertisements_channel_map = channel_map;
5360     hci_stack->le_advertisements_filter_policy = filter_policy;
5361     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5362                  6);
5363 
5364     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5365     hci_run();
5366  }
5367 
5368 /**
5369  * @brief Enable/Disable Advertisements
5370  * @param enabled
5371  */
5372 void gap_advertisements_enable(int enabled){
5373     hci_stack->le_advertisements_enabled = enabled != 0;
5374     hci_update_advertisements_enabled_for_current_roles();
5375     hci_run();
5376 }
5377 
5378 #endif
5379 
5380 void hci_le_set_own_address_type(uint8_t own_address_type){
5381     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5382     if (own_address_type == hci_stack->le_own_addr_type) return;
5383     hci_stack->le_own_addr_type = own_address_type;
5384 
5385 #ifdef ENABLE_LE_PERIPHERAL
5386     // update advertisement parameters, too
5387     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5388     hci_run();
5389 #endif
5390 #ifdef ENABLE_LE_CENTRAL
5391     // note: we don't update scan parameters or modify ongoing connection attempts
5392 #endif
5393 }
5394 
5395 #endif
5396 
5397 uint8_t gap_disconnect(hci_con_handle_t handle){
5398     hci_connection_t * conn = hci_connection_for_handle(handle);
5399     if (!conn){
5400         hci_emit_disconnection_complete(handle, 0);
5401         return 0;
5402     }
5403     // ignore if already disconnected
5404     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5405         return 0;
5406     }
5407     conn->state = SEND_DISCONNECT;
5408     hci_run();
5409     return 0;
5410 }
5411 
5412 int gap_read_rssi(hci_con_handle_t con_handle){
5413     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5414     if (hci_connection == NULL) return 0;
5415     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5416     hci_run();
5417     return 1;
5418 }
5419 
5420 /**
5421  * @brief Get connection type
5422  * @param con_handle
5423  * @result connection_type
5424  */
5425 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5426     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5427     if (!conn) return GAP_CONNECTION_INVALID;
5428     switch (conn->address_type){
5429         case BD_ADDR_TYPE_LE_PUBLIC:
5430         case BD_ADDR_TYPE_LE_RANDOM:
5431             return GAP_CONNECTION_LE;
5432         case BD_ADDR_TYPE_SCO:
5433             return GAP_CONNECTION_SCO;
5434         case BD_ADDR_TYPE_ACL:
5435             return GAP_CONNECTION_ACL;
5436         default:
5437             return GAP_CONNECTION_INVALID;
5438     }
5439 }
5440 
5441 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5442     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5443     if (!conn) return HCI_ROLE_INVALID;
5444     return (hci_role_t) conn->role;
5445 }
5446 
5447 
5448 #ifdef ENABLE_CLASSIC
5449 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5450     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5451     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5452     conn->request_role = role;
5453     hci_run();
5454     return ERROR_CODE_SUCCESS;
5455 }
5456 #endif
5457 
5458 #ifdef ENABLE_BLE
5459 
5460 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){
5461     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5462     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5463 
5464     conn->le_phy_update_all_phys    = all_phys;
5465     conn->le_phy_update_tx_phys     = tx_phys;
5466     conn->le_phy_update_rx_phys     = rx_phys;
5467     conn->le_phy_update_phy_options = phy_options;
5468 
5469     hci_run();
5470 
5471     return 0;
5472 }
5473 
5474 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5475     // check if already in list
5476     btstack_linked_list_iterator_t it;
5477     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5478     while (btstack_linked_list_iterator_has_next(&it)) {
5479         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5480         if (entry->address_type != address_type) {
5481             continue;
5482         }
5483         if (memcmp(entry->address, address, 6) != 0) {
5484             continue;
5485         }
5486 		// disallow if already scheduled to add
5487 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
5488 			return ERROR_CODE_COMMAND_DISALLOWED;
5489 		}
5490 		// still on controller, but scheduled to remove -> re-add
5491 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
5492 		return ERROR_CODE_SUCCESS;
5493     }
5494     // alloc and add to list
5495     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5496     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5497     entry->address_type = address_type;
5498     (void)memcpy(entry->address, address, 6);
5499     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5500     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5501     return ERROR_CODE_SUCCESS;
5502 }
5503 
5504 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5505     btstack_linked_list_iterator_t it;
5506     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5507     while (btstack_linked_list_iterator_has_next(&it)){
5508         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5509         if (entry->address_type != address_type) {
5510             continue;
5511         }
5512         if (memcmp(entry->address, address, 6) != 0) {
5513             continue;
5514         }
5515         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5516             // remove from controller if already present
5517             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5518         }  else {
5519             // directly remove entry from whitelist
5520             btstack_linked_list_iterator_remove(&it);
5521             btstack_memory_whitelist_entry_free(entry);
5522         }
5523         return ERROR_CODE_SUCCESS;
5524     }
5525     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5526 }
5527 
5528 static void hci_whitelist_clear(void){
5529     btstack_linked_list_iterator_t it;
5530     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5531     while (btstack_linked_list_iterator_has_next(&it)){
5532         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5533         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5534             // remove from controller if already present
5535             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5536             continue;
5537         }
5538         // directly remove entry from whitelist
5539         btstack_linked_list_iterator_remove(&it);
5540         btstack_memory_whitelist_entry_free(entry);
5541     }
5542 }
5543 
5544 /**
5545  * @brief Clear Whitelist
5546  * @returns 0 if ok
5547  */
5548 uint8_t gap_whitelist_clear(void){
5549     hci_whitelist_clear();
5550     hci_run();
5551     return ERROR_CODE_SUCCESS;
5552 }
5553 
5554 /**
5555  * @brief Add Device to Whitelist
5556  * @param address_typ
5557  * @param address
5558  * @returns 0 if ok
5559  */
5560 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5561     uint8_t status = hci_whitelist_add(address_type, address);
5562     if (status){
5563         return status;
5564     }
5565     hci_run();
5566     return ERROR_CODE_SUCCESS;
5567 }
5568 
5569 /**
5570  * @brief Remove Device from Whitelist
5571  * @param address_typ
5572  * @param address
5573  * @returns 0 if ok
5574  */
5575 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5576     uint8_t status = hci_whitelist_remove(address_type, address);
5577     if (status){
5578         return status;
5579     }
5580     hci_run();
5581     return ERROR_CODE_SUCCESS;
5582 }
5583 
5584 #ifdef ENABLE_LE_CENTRAL
5585 /**
5586  *  @brief Connect with Whitelist
5587  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5588  *  @returns - if ok
5589  */
5590 uint8_t gap_connect_with_whitelist(void){
5591     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5592         return ERROR_CODE_COMMAND_DISALLOWED;
5593     }
5594     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5595     hci_run();
5596     return ERROR_CODE_SUCCESS;
5597 }
5598 
5599 /**
5600  * @brief Auto Connection Establishment - Start Connecting to device
5601  * @param address_typ
5602  * @param address
5603  * @returns 0 if ok
5604  */
5605 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
5606     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5607         return ERROR_CODE_COMMAND_DISALLOWED;
5608     }
5609 
5610     uint8_t status = hci_whitelist_add(address_type, address);
5611     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5612         return status;
5613     }
5614 
5615     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5616 
5617     hci_run();
5618     return ERROR_CODE_SUCCESS;
5619 }
5620 
5621 /**
5622  * @brief Auto Connection Establishment - Stop Connecting to device
5623  * @param address_typ
5624  * @param address
5625  * @returns 0 if ok
5626  */
5627 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
5628     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5629         return ERROR_CODE_COMMAND_DISALLOWED;
5630     }
5631 
5632     hci_whitelist_remove(address_type, address);
5633     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5634         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5635     }
5636     hci_run();
5637     return 0;
5638 }
5639 
5640 /**
5641  * @brief Auto Connection Establishment - Stop everything
5642  * @note  Convenience function to stop all active auto connection attempts
5643  */
5644 uint8_t gap_auto_connection_stop_all(void){
5645     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5646         return ERROR_CODE_COMMAND_DISALLOWED;
5647     }
5648     hci_whitelist_clear();
5649     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5650     hci_run();
5651     return ERROR_CODE_SUCCESS;
5652 }
5653 
5654 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5655     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5656     if (!conn) return 0;
5657     return conn->le_connection_interval;
5658 }
5659 #endif
5660 #endif
5661 
5662 #ifdef ENABLE_CLASSIC
5663 /**
5664  * @brief Set Extended Inquiry Response data
5665  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5666  * @note has to be done before stack starts up
5667  */
5668 void gap_set_extended_inquiry_response(const uint8_t * data){
5669     hci_stack->eir_data = data;
5670 }
5671 
5672 /**
5673  * @brief Start GAP Classic Inquiry
5674  * @param duration in 1.28s units
5675  * @return 0 if ok
5676  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5677  */
5678 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5679     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5680     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5681     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5682         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5683     }
5684     hci_stack->inquiry_state = duration_in_1280ms_units;
5685     hci_run();
5686     return 0;
5687 }
5688 
5689 /**
5690  * @brief Stop GAP Classic Inquiry
5691  * @returns 0 if ok
5692  */
5693 int gap_inquiry_stop(void){
5694     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5695         // emit inquiry complete event, before it even started
5696         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5697         hci_emit_event(event, sizeof(event), 1);
5698         return 0;
5699     }
5700     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5701     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5702     hci_run();
5703     return 0;
5704 }
5705 
5706 
5707 /**
5708  * @brief Remote Name Request
5709  * @param addr
5710  * @param page_scan_repetition_mode
5711  * @param clock_offset only used when bit 15 is set
5712  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5713  */
5714 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5715     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5716     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5717     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5718     hci_stack->remote_name_clock_offset = clock_offset;
5719     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5720     hci_run();
5721     return 0;
5722 }
5723 
5724 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
5725     hci_stack->gap_pairing_state = state;
5726     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5727     hci_run();
5728     return 0;
5729 }
5730 
5731 /**
5732  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5733  * @param addr
5734  * @param pin_data
5735  * @param pin_len
5736  * @return 0 if ok
5737  */
5738 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5739     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5740     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5741     hci_stack->gap_pairing_pin_len = pin_len;
5742     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5743 }
5744 
5745 /**
5746  * @brief Legacy Pairing Pin Code Response
5747  * @param addr
5748  * @param pin
5749  * @return 0 if ok
5750  */
5751 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
5752     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5753 }
5754 
5755 /**
5756  * @brief Abort Legacy Pairing
5757  * @param addr
5758  * @param pin
5759  * @return 0 if ok
5760  */
5761 int gap_pin_code_negative(bd_addr_t addr){
5762     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5763     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5764 }
5765 
5766 /**
5767  * @brief SSP Passkey Response
5768  * @param addr
5769  * @param passkey
5770  * @return 0 if ok
5771  */
5772 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
5773     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5774     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5775     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5776 }
5777 
5778 /**
5779  * @brief Abort SSP Passkey Entry/Pairing
5780  * @param addr
5781  * @param pin
5782  * @return 0 if ok
5783  */
5784 int gap_ssp_passkey_negative(const bd_addr_t addr){
5785     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5786     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5787 }
5788 
5789 /**
5790  * @brief Accept SSP Numeric Comparison
5791  * @param addr
5792  * @param passkey
5793  * @return 0 if ok
5794  */
5795 int gap_ssp_confirmation_response(const bd_addr_t addr){
5796     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5797     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5798 }
5799 
5800 /**
5801  * @brief Abort SSP Numeric Comparison/Pairing
5802  * @param addr
5803  * @param pin
5804  * @return 0 if ok
5805  */
5806 int gap_ssp_confirmation_negative(const bd_addr_t addr){
5807     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5808     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5809 }
5810 
5811 /**
5812  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5813  * @param inquiry_mode see bluetooth_defines.h
5814  */
5815 void hci_set_inquiry_mode(inquiry_mode_t mode){
5816     hci_stack->inquiry_mode = mode;
5817 }
5818 
5819 /**
5820  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5821  */
5822 void hci_set_sco_voice_setting(uint16_t voice_setting){
5823     hci_stack->sco_voice_setting = voice_setting;
5824 }
5825 
5826 /**
5827  * @brief Get SCO Voice Setting
5828  * @return current voice setting
5829  */
5830 uint16_t hci_get_sco_voice_setting(void){
5831     return hci_stack->sco_voice_setting;
5832 }
5833 
5834 static int hci_have_usb_transport(void){
5835     if (!hci_stack->hci_transport) return 0;
5836     const char * transport_name = hci_stack->hci_transport->name;
5837     if (!transport_name) return 0;
5838     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5839 }
5840 
5841 /** @brief Get SCO packet length for current SCO Voice setting
5842  *  @note  Using SCO packets of the exact length is required for USB transfer
5843  *  @return Length of SCO packets in bytes (not audio frames)
5844  */
5845 int hci_get_sco_packet_length(void){
5846     int sco_packet_length = 0;
5847 
5848 #ifdef ENABLE_SCO_OVER_HCI
5849 
5850     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5851     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5852 
5853     if (hci_have_usb_transport()){
5854         // see Core Spec for H2 USB Transfer.
5855         // 3 byte SCO header + 24 bytes per connection
5856         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5857         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5858     } else {
5859         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5860         sco_packet_length = 3 + 60 * multiplier;
5861         // assert that it still fits inside an SCO buffer
5862         if (sco_packet_length > hci_stack->sco_data_packet_length){
5863             sco_packet_length = 3 + 60;
5864         }
5865     }
5866 #endif
5867     return sco_packet_length;
5868 }
5869 
5870 /**
5871 * @brief Sets the master/slave policy
5872 * @param policy (0: attempt to become master, 1: let connecting device decide)
5873 */
5874 void hci_set_master_slave_policy(uint8_t policy){
5875     hci_stack->master_slave_policy = policy;
5876 }
5877 
5878 #endif
5879 
5880 HCI_STATE hci_get_state(void){
5881     return hci_stack->state;
5882 }
5883 
5884 #ifdef ENABLE_CLASSIC
5885 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5886     hci_stack->gap_classic_accept_callback = accept_callback;
5887 }
5888 #endif
5889 
5890 /**
5891  * @brief Set callback for Bluetooth Hardware Error
5892  */
5893 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5894     hci_stack->hardware_error_callback = fn;
5895 }
5896 
5897 void hci_disconnect_all(void){
5898     btstack_linked_list_iterator_t it;
5899     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5900     while (btstack_linked_list_iterator_has_next(&it)){
5901         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5902         if (con->state == SENT_DISCONNECT) continue;
5903         con->state = SEND_DISCONNECT;
5904     }
5905     hci_run();
5906 }
5907 
5908 uint16_t hci_get_manufacturer(void){
5909     return hci_stack->manufacturer;
5910 }
5911 
5912 #ifdef ENABLE_BLE
5913 
5914 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5915     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5916     if (!hci_con) return NULL;
5917     return &hci_con->sm_connection;
5918 }
5919 
5920 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5921 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5922 
5923 int gap_encryption_key_size(hci_con_handle_t con_handle){
5924     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5925     if (hci_connection == NULL) return 0;
5926     if (hci_is_le_connection(hci_connection)){
5927         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5928         if (sm_conn->sm_connection_encrypted) {
5929             return sm_conn->sm_actual_encryption_key_size;
5930         }
5931     }
5932 #ifdef ENABLE_CLASSIC
5933     else {
5934         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5935             return hci_connection->encryption_key_size;
5936         }
5937     }
5938 #endif
5939     return 0;
5940 }
5941 
5942 int gap_authenticated(hci_con_handle_t con_handle){
5943     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5944     if (hci_connection == NULL) return 0;
5945 
5946     switch (hci_connection->address_type){
5947         case BD_ADDR_TYPE_LE_PUBLIC:
5948         case BD_ADDR_TYPE_LE_RANDOM:
5949             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5950             return hci_connection->sm_connection.sm_connection_authenticated;
5951 #ifdef ENABLE_CLASSIC
5952         case BD_ADDR_TYPE_SCO:
5953         case BD_ADDR_TYPE_ACL:
5954             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5955 #endif
5956         default:
5957             return 0;
5958     }
5959 }
5960 
5961 int gap_secure_connection(hci_con_handle_t con_handle){
5962     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5963     if (hci_connection == NULL) return 0;
5964 
5965     switch (hci_connection->address_type){
5966         case BD_ADDR_TYPE_LE_PUBLIC:
5967         case BD_ADDR_TYPE_LE_RANDOM:
5968             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5969             return hci_connection->sm_connection.sm_connection_sc;
5970 #ifdef ENABLE_CLASSIC
5971         case BD_ADDR_TYPE_SCO:
5972         case BD_ADDR_TYPE_ACL:
5973             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5974 #endif
5975         default:
5976             return 0;
5977     }
5978 }
5979 
5980 bool gap_bonded(hci_con_handle_t con_handle){
5981 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5982 	if (hci_connection == NULL) return 0;
5983 
5984 	link_key_t link_key;
5985 	link_key_type_t link_key_type;
5986 	switch (hci_connection->address_type){
5987 		case BD_ADDR_TYPE_LE_PUBLIC:
5988 		case BD_ADDR_TYPE_LE_RANDOM:
5989 			return hci_connection->sm_connection.sm_le_db_index >= 0;
5990 #ifdef ENABLE_CLASSIC
5991 		case BD_ADDR_TYPE_SCO:
5992 		case BD_ADDR_TYPE_ACL:
5993 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
5994 #endif
5995 		default:
5996 			return false;
5997 	}
5998 }
5999 
6000 
6001 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6002     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6003     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6004     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6005     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6006     return sm_conn->sm_connection_authorization_state;
6007 }
6008 #endif
6009 
6010 #ifdef ENABLE_CLASSIC
6011 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){
6012     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6013     if (!conn) return GAP_CONNECTION_INVALID;
6014     conn->sniff_min_interval = sniff_min_interval;
6015     conn->sniff_max_interval = sniff_max_interval;
6016     conn->sniff_attempt = sniff_attempt;
6017     conn->sniff_timeout = sniff_timeout;
6018     hci_run();
6019     return 0;
6020 }
6021 
6022 /**
6023  * @brief Exit Sniff mode
6024  * @param con_handle
6025  @ @return 0 if ok
6026  */
6027 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6028     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6029     if (!conn) return GAP_CONNECTION_INVALID;
6030     conn->sniff_min_interval = 0xffff;
6031     hci_run();
6032     return 0;
6033 }
6034 #endif
6035 
6036 void hci_halting_defer(void){
6037     if (hci_stack->state != HCI_STATE_HALTING) return;
6038     switch (hci_stack->substate){
6039         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6040         case HCI_HALTING_CLOSE:
6041             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6042             break;
6043         default:
6044             break;
6045     }
6046 }
6047 
6048 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6049 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6050     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6051     if (le_device_db_index >= le_device_db_max_count()) return;
6052     uint8_t offset = le_device_db_index >> 3;
6053     uint8_t mask = 1 << (le_device_db_index & 7);
6054     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6055     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6056     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6057         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6058     }
6059 }
6060 
6061 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6062 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6063 	if (le_device_db_index >= le_device_db_max_count()) return;
6064 	uint8_t offset = le_device_db_index >> 3;
6065 	uint8_t mask = 1 << (le_device_db_index & 7);
6066 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6067 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6068 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6069 	}
6070 }
6071 
6072 uint8_t gap_load_resolving_list_from_le_device_db(void){
6073 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6074 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6075 	}
6076 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6077 		// restart le resolving list update
6078 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6079 	}
6080 	return ERROR_CODE_SUCCESS;
6081 }
6082 #endif
6083 
6084 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6085 void hci_setup_test_connections_fuzz(void){
6086     hci_connection_t * conn;
6087 
6088     // default address: 66:55:44:33:00:01
6089     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6090 
6091     // setup Controller info
6092     hci_stack->num_cmd_packets = 255;
6093     hci_stack->acl_packets_total_num = 255;
6094 
6095     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6096     addr[5] = 0x01;
6097     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6098     conn->con_handle = addr[5];
6099     conn->role  = HCI_ROLE_SLAVE;
6100     conn->state = RECEIVED_CONNECTION_REQUEST;
6101     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6102 
6103     // setup incoming Classic SCO connection with con handle 0x0002
6104     addr[5] = 0x02;
6105     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6106     conn->con_handle = addr[5];
6107     conn->role  = HCI_ROLE_SLAVE;
6108     conn->state = RECEIVED_CONNECTION_REQUEST;
6109     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6110 
6111     // setup ready Classic ACL connection with con handle 0x0003
6112     addr[5] = 0x03;
6113     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6114     conn->con_handle = addr[5];
6115     conn->role  = HCI_ROLE_SLAVE;
6116     conn->state = OPEN;
6117     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6118 
6119     // setup ready Classic SCO connection with con handle 0x0004
6120     addr[5] = 0x04;
6121     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6122     conn->con_handle = addr[5];
6123     conn->role  = HCI_ROLE_SLAVE;
6124     conn->state = OPEN;
6125     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6126 
6127     // setup ready LE ACL connection with con handle 0x005 and public address
6128     addr[5] = 0x05;
6129     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6130     conn->con_handle = addr[5];
6131     conn->role  = HCI_ROLE_SLAVE;
6132     conn->state = OPEN;
6133     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6134 }
6135 
6136 void hci_free_connections_fuzz(void){
6137     btstack_linked_list_iterator_t it;
6138     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6139     while (btstack_linked_list_iterator_has_next(&it)){
6140         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6141         btstack_linked_list_iterator_remove(&it);
6142         btstack_memory_hci_connection_free(con);
6143     }
6144 }
6145 void hci_simulate_working_fuzz(void){
6146     hci_init_done();
6147     hci_stack->num_cmd_packets = 255;
6148 }
6149 #endif
6150