xref: /btstack/src/hci.c (revision 4688f21608d8de244d3b01fa5bef282cad7a41de)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->role = HCI_ROLE_INVALID;
199     conn->address_type = addr_type;
200     conn->con_handle = 0xffff;
201     conn->authentication_flags = AUTH_FLAGS_NONE;
202     conn->bonding_flags = 0;
203     conn->requested_security_level = LEVEL_0;
204 #ifdef ENABLE_CLASSIC
205     conn->request_role = HCI_ROLE_INVALID;
206     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
207     btstack_run_loop_set_timer_context(&conn->timeout, conn);
208     hci_connection_timestamp(conn);
209 #endif
210     conn->acl_recombination_length = 0;
211     conn->acl_recombination_pos = 0;
212     conn->num_packets_sent = 0;
213 
214     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
215 #ifdef ENABLE_BLE
216     conn->le_phy_update_all_phys = 0xff;
217 #endif
218 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
219     conn->le_max_tx_octets = 27;
220 #endif
221     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
222     return conn;
223 }
224 
225 
226 /**
227  * get le connection parameter range
228 *
229  * @return le connection parameter range struct
230  */
231 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
232     *range = hci_stack->le_connection_parameter_range;
233 }
234 
235 /**
236  * set le connection parameter range
237  *
238  */
239 
240 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
241     hci_stack->le_connection_parameter_range = *range;
242 }
243 
244 /**
245  * @brief Test if connection parameters are inside in existing rage
246  * @param conn_interval_min (unit: 1.25ms)
247  * @param conn_interval_max (unit: 1.25ms)
248  * @param conn_latency
249  * @param supervision_timeout (unit: 10ms)
250  * @returns 1 if included
251  */
252 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
253     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
254     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
255 
256     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
257     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
258 
259     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
260     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
261 
262     return 1;
263 }
264 
265 /**
266  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
267  * @note: default: 1
268  * @param max_peripheral_connections
269  */
270 #ifdef ENABLE_LE_PERIPHERAL
271 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
272     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
273 }
274 #endif
275 
276 /**
277  * get hci connections iterator
278  *
279  * @return hci connections iterator
280  */
281 
282 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
283     btstack_linked_list_iterator_init(it, &hci_stack->connections);
284 }
285 
286 /**
287  * get connection for a given handle
288  *
289  * @return connection OR NULL, if not found
290  */
291 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
292     btstack_linked_list_iterator_t it;
293     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
294     while (btstack_linked_list_iterator_has_next(&it)){
295         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
296         if ( item->con_handle == con_handle ) {
297             return item;
298         }
299     }
300     return NULL;
301 }
302 
303 /**
304  * get connection for given address
305  *
306  * @return connection OR NULL, if not found
307  */
308 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
309     btstack_linked_list_iterator_t it;
310     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
311     while (btstack_linked_list_iterator_has_next(&it)){
312         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
313         if (connection->address_type != addr_type)  continue;
314         if (memcmp(addr, connection->address, 6) != 0) continue;
315         return connection;
316     }
317     return NULL;
318 }
319 
320 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
321     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
322 }
323 
324 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
325     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
326 }
327 
328 #ifdef ENABLE_CLASSIC
329 
330 #ifdef ENABLE_SCO_OVER_HCI
331 static int hci_number_sco_connections(void){
332     int connections = 0;
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
338         connections++;
339     }
340     return connections;
341 }
342 #endif
343 
344 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
345     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
346 #ifdef HAVE_EMBEDDED_TICK
347     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
348         // connections might be timed out
349         hci_emit_l2cap_check_timeout(connection);
350     }
351 #else
352     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
353         // connections might be timed out
354         hci_emit_l2cap_check_timeout(connection);
355     }
356 #endif
357 }
358 
359 static void hci_connection_timestamp(hci_connection_t *connection){
360 #ifdef HAVE_EMBEDDED_TICK
361     connection->timestamp = btstack_run_loop_embedded_get_ticks();
362 #else
363     connection->timestamp = btstack_run_loop_get_time_ms();
364 #endif
365 }
366 
367 /**
368  * add authentication flags and reset timer
369  * @note: assumes classic connection
370  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
371  */
372 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
373     bd_addr_t addr;
374     reverse_bd_addr(bd_addr, addr);
375     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
376     if (conn) {
377         connectionSetAuthenticationFlags(conn, flags);
378         hci_connection_timestamp(conn);
379     }
380 }
381 
382 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
383     hci_connection_t * conn = hci_connection_for_handle(handle);
384     if (!conn) return 0;
385     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
386     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
387     return 0;
388 }
389 
390 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
391     if (!hci_stack->link_key_db) return;
392     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
393     hci_stack->link_key_db->delete_link_key(addr);
394 }
395 
396 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
397     if (!hci_stack->link_key_db) return;
398     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
399     hci_stack->link_key_db->put_link_key(addr, link_key, type);
400 }
401 
402 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
403 	if (!hci_stack->link_key_db) return false;
404 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
405 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
406 	return result;
407 }
408 
409 void gap_delete_all_link_keys(void){
410     bd_addr_t  addr;
411     link_key_t link_key;
412     link_key_type_t type;
413     btstack_link_key_iterator_t it;
414     int ok = gap_link_key_iterator_init(&it);
415     if (!ok) {
416         log_error("could not initialize iterator");
417         return;
418     }
419     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
420         gap_drop_link_key_for_bd_addr(addr);
421     }
422     gap_link_key_iterator_done(&it);
423 }
424 
425 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
426     if (!hci_stack->link_key_db) return 0;
427     if (!hci_stack->link_key_db->iterator_init) return 0;
428     return hci_stack->link_key_db->iterator_init(it);
429 }
430 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
431     if (!hci_stack->link_key_db) return 0;
432     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
433 }
434 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
435     if (!hci_stack->link_key_db) return;
436     hci_stack->link_key_db->iterator_done(it);
437 }
438 #endif
439 
440 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
441     switch (address_type){
442         case BD_ADDR_TYPE_LE_PUBLIC:
443         case BD_ADDR_TYPE_LE_RANDOM:
444         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
445         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
446             return true;
447         default:
448             return false;
449     }
450 }
451 
452 static int hci_is_le_connection(hci_connection_t * connection){
453     return hci_is_le_connection_type(connection->address_type);
454 }
455 
456 /**
457  * count connections
458  */
459 static int nr_hci_connections(void){
460     int count = 0;
461     btstack_linked_item_t *it;
462     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
463         count++;
464     }
465     return count;
466 }
467 
468 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
469 
470     unsigned int num_packets_sent_classic = 0;
471     unsigned int num_packets_sent_le = 0;
472 
473     btstack_linked_item_t *it;
474     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
475         hci_connection_t * connection = (hci_connection_t *) it;
476         if (hci_is_le_connection(connection)){
477             num_packets_sent_le += connection->num_packets_sent;
478         }
479         if (connection->address_type == BD_ADDR_TYPE_ACL){
480             num_packets_sent_classic += connection->num_packets_sent;
481         }
482     }
483     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
484     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
485     int free_slots_le = 0;
486 
487     if (free_slots_classic < 0){
488         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
489         return 0;
490     }
491 
492     if (hci_stack->le_acl_packets_total_num){
493         // if we have LE slots, they are used
494         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
495         if (free_slots_le < 0){
496             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
497             return 0;
498         }
499     } else {
500         // otherwise, classic slots are used for LE, too
501         free_slots_classic -= num_packets_sent_le;
502         if (free_slots_classic < 0){
503             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
504             return 0;
505         }
506     }
507 
508     switch (address_type){
509         case BD_ADDR_TYPE_UNKNOWN:
510             log_error("hci_number_free_acl_slots: unknown address type");
511             return 0;
512 
513         case BD_ADDR_TYPE_ACL:
514             return free_slots_classic;
515 
516         default:
517            if (hci_stack->le_acl_packets_total_num){
518                return free_slots_le;
519            }
520            return free_slots_classic;
521     }
522 }
523 
524 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
525     // get connection type
526     hci_connection_t * connection = hci_connection_for_handle(con_handle);
527     if (!connection){
528         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
529         return 0;
530     }
531     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
532 }
533 
534 #ifdef ENABLE_CLASSIC
535 static int hci_number_free_sco_slots(void){
536     unsigned int num_sco_packets_sent  = 0;
537     btstack_linked_item_t *it;
538     if (hci_stack->synchronous_flow_control_enabled){
539         // explicit flow control
540         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
541             hci_connection_t * connection = (hci_connection_t *) it;
542             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
543             num_sco_packets_sent += connection->num_packets_sent;
544         }
545         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
546             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
547             return 0;
548         }
549         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
550     } else {
551         // implicit flow control -- TODO
552         int num_ready = 0;
553         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
554             hci_connection_t * connection = (hci_connection_t *) it;
555             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
556             if (connection->sco_tx_ready == 0) continue;
557             num_ready++;
558         }
559         return num_ready;
560     }
561 }
562 #endif
563 
564 // only used to send HCI Host Number Completed Packets
565 static int hci_can_send_comand_packet_transport(void){
566     if (hci_stack->hci_packet_buffer_reserved) return 0;
567 
568     // check for async hci transport implementations
569     if (hci_stack->hci_transport->can_send_packet_now){
570         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
571             return 0;
572         }
573     }
574     return 1;
575 }
576 
577 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
578 int hci_can_send_command_packet_now(void){
579     if (hci_can_send_comand_packet_transport() == 0) return 0;
580     return hci_stack->num_cmd_packets > 0u;
581 }
582 
583 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
584     // check for async hci transport implementations
585     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
586     return hci_stack->hci_transport->can_send_packet_now(packet_type);
587 }
588 
589 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
590     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
591     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
592 }
593 
594 int hci_can_send_acl_le_packet_now(void){
595     if (hci_stack->hci_packet_buffer_reserved) return 0;
596     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
597 }
598 
599 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
600     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
601     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
602 }
603 
604 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
605     if (hci_stack->hci_packet_buffer_reserved) return 0;
606     return hci_can_send_prepared_acl_packet_now(con_handle);
607 }
608 
609 #ifdef ENABLE_CLASSIC
610 int hci_can_send_acl_classic_packet_now(void){
611     if (hci_stack->hci_packet_buffer_reserved) return 0;
612     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
613 }
614 
615 int hci_can_send_prepared_sco_packet_now(void){
616     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
617     if (hci_have_usb_transport()){
618         return hci_stack->sco_can_send_now;
619     } else {
620         return hci_number_free_sco_slots() > 0;
621     }
622 }
623 
624 int hci_can_send_sco_packet_now(void){
625     if (hci_stack->hci_packet_buffer_reserved) return 0;
626     return hci_can_send_prepared_sco_packet_now();
627 }
628 
629 void hci_request_sco_can_send_now_event(void){
630     hci_stack->sco_waiting_for_can_send_now = 1;
631     hci_notify_if_sco_can_send_now();
632 }
633 #endif
634 
635 // used for internal checks in l2cap.c
636 int hci_is_packet_buffer_reserved(void){
637     return hci_stack->hci_packet_buffer_reserved;
638 }
639 
640 // reserves outgoing packet buffer. @returns 1 if successful
641 int hci_reserve_packet_buffer(void){
642     if (hci_stack->hci_packet_buffer_reserved) {
643         log_error("hci_reserve_packet_buffer called but buffer already reserved");
644         return 0;
645     }
646     hci_stack->hci_packet_buffer_reserved = 1;
647     return 1;
648 }
649 
650 void hci_release_packet_buffer(void){
651     hci_stack->hci_packet_buffer_reserved = 0;
652 }
653 
654 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
655 static int hci_transport_synchronous(void){
656     return hci_stack->hci_transport->can_send_packet_now == NULL;
657 }
658 
659 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
660 
661     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
662 
663     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
664     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
665     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
666         max_acl_data_packet_length = hci_stack->le_data_packets_length;
667     }
668 
669 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
670     if (hci_is_le_connection(connection)){
671         max_acl_data_packet_length = connection->le_max_tx_octets;
672     }
673 #endif
674 
675     log_debug("hci_send_acl_packet_fragments entered");
676 
677     int err;
678     // multiple packets could be send on a synchronous HCI transport
679     while (true){
680 
681         log_debug("hci_send_acl_packet_fragments loop entered");
682 
683         // get current data
684         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
685         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
686         int more_fragments = 0;
687 
688         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
689         if (current_acl_data_packet_length > max_acl_data_packet_length){
690             more_fragments = 1;
691             current_acl_data_packet_length = max_acl_data_packet_length;
692         }
693 
694         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
695         if (acl_header_pos > 0u){
696             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
697             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
698             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
699         }
700 
701         // update header len
702         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
703 
704         // count packet
705         connection->num_packets_sent++;
706         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
707 
708         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
709         if (more_fragments){
710             // update start of next fragment to send
711             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
712         } else {
713             // done
714             hci_stack->acl_fragmentation_pos = 0;
715             hci_stack->acl_fragmentation_total_size = 0;
716         }
717 
718         // send packet
719         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
720         const int size = current_acl_data_packet_length + 4;
721         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
722         hci_stack->acl_fragmentation_tx_active = 1;
723         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
724 
725         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
726 
727         // done yet?
728         if (!more_fragments) break;
729 
730         // can send more?
731         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
732     }
733 
734     log_debug("hci_send_acl_packet_fragments loop over");
735 
736     // release buffer now for synchronous transport
737     if (hci_transport_synchronous()){
738         hci_stack->acl_fragmentation_tx_active = 0;
739         hci_release_packet_buffer();
740         hci_emit_transport_packet_sent();
741     }
742 
743     return err;
744 }
745 
746 // pre: caller has reserved the packet buffer
747 int hci_send_acl_packet_buffer(int size){
748 
749     // log_info("hci_send_acl_packet_buffer size %u", size);
750 
751     if (!hci_stack->hci_packet_buffer_reserved) {
752         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
753         return 0;
754     }
755 
756     uint8_t * packet = hci_stack->hci_packet_buffer;
757     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
758 
759     // check for free places on Bluetooth module
760     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
761         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
762         hci_release_packet_buffer();
763         hci_emit_transport_packet_sent();
764         return BTSTACK_ACL_BUFFERS_FULL;
765     }
766 
767     hci_connection_t *connection = hci_connection_for_handle( con_handle);
768     if (!connection) {
769         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
770         hci_release_packet_buffer();
771         hci_emit_transport_packet_sent();
772         return 0;
773     }
774 
775 #ifdef ENABLE_CLASSIC
776     hci_connection_timestamp(connection);
777 #endif
778 
779     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
780 
781     // setup data
782     hci_stack->acl_fragmentation_total_size = size;
783     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
784 
785     return hci_send_acl_packet_fragments(connection);
786 }
787 
788 #ifdef ENABLE_CLASSIC
789 // pre: caller has reserved the packet buffer
790 int hci_send_sco_packet_buffer(int size){
791 
792     // log_info("hci_send_acl_packet_buffer size %u", size);
793 
794     if (!hci_stack->hci_packet_buffer_reserved) {
795         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
796         return 0;
797     }
798 
799     uint8_t * packet = hci_stack->hci_packet_buffer;
800 
801     // skip checks in loopback mode
802     if (!hci_stack->loopback_mode){
803         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
804 
805         // check for free places on Bluetooth module
806         if (!hci_can_send_prepared_sco_packet_now()) {
807             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
808             hci_release_packet_buffer();
809             hci_emit_transport_packet_sent();
810             return BTSTACK_ACL_BUFFERS_FULL;
811         }
812 
813         // track send packet in connection struct
814         hci_connection_t *connection = hci_connection_for_handle( con_handle);
815         if (!connection) {
816             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
817             hci_release_packet_buffer();
818             hci_emit_transport_packet_sent();
819             return 0;
820         }
821 
822         if (hci_have_usb_transport()){
823             // token used
824             hci_stack->sco_can_send_now = 0;
825         } else {
826             if (hci_stack->synchronous_flow_control_enabled){
827                 connection->num_packets_sent++;
828             } else {
829                 connection->sco_tx_ready--;
830             }
831         }
832     }
833 
834     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
835     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
836 
837     if (hci_transport_synchronous()){
838         hci_release_packet_buffer();
839         hci_emit_transport_packet_sent();
840     }
841 
842     return err;
843 }
844 #endif
845 
846 static void acl_handler(uint8_t *packet, uint16_t size){
847 
848     // get info
849     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
850     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
851     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
852     uint16_t acl_length         = READ_ACL_LENGTH(packet);
853 
854     // ignore non-registered handle
855     if (!conn){
856         log_error("acl_handler called with non-registered handle %u!" , con_handle);
857         return;
858     }
859 
860     // assert packet is complete
861     if ((acl_length + 4u) != size){
862         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
863         return;
864     }
865 
866 #ifdef ENABLE_CLASSIC
867     // update idle timestamp
868     hci_connection_timestamp(conn);
869 #endif
870 
871 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
872     hci_stack->host_completed_packets = 1;
873     conn->num_packets_completed++;
874 #endif
875 
876     // handle different packet types
877     switch (acl_flags & 0x03u) {
878 
879         case 0x01: // continuation fragment
880 
881             // sanity checks
882             if (conn->acl_recombination_pos == 0u) {
883                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
884                 return;
885             }
886             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
887                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
888                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
889                 conn->acl_recombination_pos = 0;
890                 return;
891             }
892 
893             // append fragment payload (header already stored)
894             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
895                          &packet[4], acl_length);
896             conn->acl_recombination_pos += acl_length;
897 
898             // forward complete L2CAP packet if complete.
899             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
900                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
901                 // reset recombination buffer
902                 conn->acl_recombination_length = 0;
903                 conn->acl_recombination_pos = 0;
904             }
905             break;
906 
907         case 0x02: { // first fragment
908 
909             // sanity check
910             if (conn->acl_recombination_pos) {
911                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
912                 conn->acl_recombination_pos = 0;
913             }
914 
915             // peek into L2CAP packet!
916             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
917 
918             // compare fragment size to L2CAP packet size
919             if (acl_length >= (l2cap_length + 4u)){
920                 // forward fragment as L2CAP packet
921                 hci_emit_acl_packet(packet, acl_length + 4u);
922             } else {
923 
924                 if (acl_length > HCI_ACL_BUFFER_SIZE){
925                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
926                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
927                     return;
928                 }
929 
930                 // store first fragment and tweak acl length for complete package
931                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
932                              packet, acl_length + 4u);
933                 conn->acl_recombination_pos    = acl_length + 4u;
934                 conn->acl_recombination_length = l2cap_length;
935                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
936             }
937             break;
938 
939         }
940         default:
941             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
942             return;
943     }
944 
945     // execute main loop
946     hci_run();
947 }
948 
949 static void hci_shutdown_connection(hci_connection_t *conn){
950     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
951 
952 #ifdef ENABLE_CLASSIC
953 #ifdef ENABLE_SCO_OVER_HCI
954     int addr_type = conn->address_type;
955 #endif
956 #endif
957 
958     btstack_run_loop_remove_timer(&conn->timeout);
959 
960     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
961     btstack_memory_hci_connection_free( conn );
962 
963     // now it's gone
964     hci_emit_nr_connections_changed();
965 
966 #ifdef ENABLE_CLASSIC
967 #ifdef ENABLE_SCO_OVER_HCI
968     // update SCO
969     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
970         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
971     }
972 #endif
973 #endif
974 }
975 
976 #ifdef ENABLE_CLASSIC
977 
978 static const uint16_t packet_type_sizes[] = {
979     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
980     HCI_ACL_DH1_SIZE, 0, 0, 0,
981     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
982     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
983 };
984 static const uint8_t  packet_type_feature_requirement_bit[] = {
985      0, // 3 slot packets
986      1, // 5 slot packets
987     25, // EDR 2 mpbs
988     26, // EDR 3 mbps
989     39, // 3 slot EDR packts
990     40, // 5 slot EDR packet
991 };
992 static const uint16_t packet_type_feature_packet_mask[] = {
993     0x0f00, // 3 slot packets
994     0xf000, // 5 slot packets
995     0x1102, // EDR 2 mpbs
996     0x2204, // EDR 3 mbps
997     0x0300, // 3 slot EDR packts
998     0x3000, // 5 slot EDR packet
999 };
1000 
1001 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1002     // enable packet types based on size
1003     uint16_t packet_types = 0;
1004     unsigned int i;
1005     for (i=0;i<16;i++){
1006         if (packet_type_sizes[i] == 0) continue;
1007         if (packet_type_sizes[i] <= buffer_size){
1008             packet_types |= 1 << i;
1009         }
1010     }
1011     // disable packet types due to missing local supported features
1012     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1013         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1014         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1015         if (feature_set) continue;
1016         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1017         packet_types &= ~packet_type_feature_packet_mask[i];
1018     }
1019     // flip bits for "may not be used"
1020     packet_types ^= 0x3306;
1021     return packet_types;
1022 }
1023 
1024 uint16_t hci_usable_acl_packet_types(void){
1025     return hci_stack->packet_types;
1026 }
1027 #endif
1028 
1029 uint8_t* hci_get_outgoing_packet_buffer(void){
1030     // hci packet buffer is >= acl data packet length
1031     return hci_stack->hci_packet_buffer;
1032 }
1033 
1034 uint16_t hci_max_acl_data_packet_length(void){
1035     return hci_stack->acl_data_packet_length;
1036 }
1037 
1038 #ifdef ENABLE_CLASSIC
1039 int hci_extended_sco_link_supported(void){
1040     // No. 31, byte 3, bit 7
1041     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1042 }
1043 #endif
1044 
1045 int hci_non_flushable_packet_boundary_flag_supported(void){
1046     // No. 54, byte 6, bit 6
1047     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1048 }
1049 
1050 static int gap_ssp_supported(void){
1051     // No. 51, byte 6, bit 3
1052     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1053 }
1054 
1055 static int hci_classic_supported(void){
1056 #ifdef ENABLE_CLASSIC
1057     // No. 37, byte 4, bit 5, = No BR/EDR Support
1058     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1059 #else
1060     return 0;
1061 #endif
1062 }
1063 
1064 static int hci_le_supported(void){
1065 #ifdef ENABLE_BLE
1066     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1067     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1068 #else
1069     return 0;
1070 #endif
1071 }
1072 
1073 #ifdef ENABLE_BLE
1074 
1075 /**
1076  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1077  */
1078 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1079     *addr_type = hci_stack->le_own_addr_type;
1080     if (hci_stack->le_own_addr_type){
1081         (void)memcpy(addr, hci_stack->le_random_address, 6);
1082     } else {
1083         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1084     }
1085 }
1086 
1087 #ifdef ENABLE_LE_CENTRAL
1088 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1089 
1090     int offset = 3;
1091     int num_reports = packet[offset];
1092     offset += 1;
1093 
1094     int i;
1095     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1096     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1097     for (i=0; (i<num_reports) && (offset < size);i++){
1098         // sanity checks on data_length:
1099         uint8_t data_length = packet[offset + 8];
1100         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1101         if ((offset + 9u + data_length + 1u) > size)    return;
1102         // setup event
1103         uint8_t event_size = 10u + data_length;
1104         int pos = 0;
1105         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1106         event[pos++] = event_size;
1107         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1108         offset += 8;
1109         pos += 8;
1110         event[pos++] = packet[offset + 1 + data_length]; // rssi
1111         event[pos++] = data_length;
1112         offset++;
1113         (void)memcpy(&event[pos], &packet[offset], data_length);
1114         pos +=    data_length;
1115         offset += data_length + 1u; // rssi
1116         hci_emit_event(event, pos, 1);
1117     }
1118 }
1119 #endif
1120 #endif
1121 
1122 #ifdef ENABLE_BLE
1123 #ifdef ENABLE_LE_PERIPHERAL
1124 static void hci_update_advertisements_enabled_for_current_roles(void){
1125     if (hci_stack->le_advertisements_enabled){
1126         // get number of active le slave connections
1127         int num_slave_connections = 0;
1128         btstack_linked_list_iterator_t it;
1129         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1130         while (btstack_linked_list_iterator_has_next(&it)){
1131             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1132             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1133             if (con->state != OPEN) continue;
1134             if (con->role  != HCI_ROLE_SLAVE) continue;
1135             if (!hci_is_le_connection(con)) continue;
1136             num_slave_connections++;
1137         }
1138         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1139         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1140     } else {
1141         hci_stack->le_advertisements_enabled_for_current_roles = false;
1142     }
1143 }
1144 #endif
1145 #endif
1146 
1147 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1148 
1149 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1150     if (!hci_stack->config) return 0;
1151     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1152     // Limit baud rate for Broadcom chipsets to 3 mbps
1153     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1154         baud_rate = 3000000;
1155     }
1156     return baud_rate;
1157 }
1158 
1159 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1160     UNUSED(ds);
1161 
1162     switch (hci_stack->substate){
1163         case HCI_INIT_W4_SEND_RESET:
1164             log_info("Resend HCI Reset");
1165             hci_stack->substate = HCI_INIT_SEND_RESET;
1166             hci_stack->num_cmd_packets = 1;
1167             hci_run();
1168             break;
1169         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1170             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1171             if (hci_stack->hci_transport->reset_link){
1172                 hci_stack->hci_transport->reset_link();
1173             }
1174 
1175             /* fall through */
1176 
1177         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1178             log_info("Resend HCI Reset - CSR Warm Boot");
1179             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1180             hci_stack->num_cmd_packets = 1;
1181             hci_run();
1182             break;
1183         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1184             if (hci_stack->hci_transport->set_baudrate){
1185                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1186                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1187                 hci_stack->hci_transport->set_baudrate(baud_rate);
1188             }
1189             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1190             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1191                 if (hci_stack->hci_transport->reset_link){
1192                     log_info("Link Reset");
1193                     hci_stack->hci_transport->reset_link();
1194                 }
1195                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1196                 hci_run();
1197             }
1198             break;
1199         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1200             // otherwise continue
1201             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1202             hci_send_cmd(&hci_read_local_supported_commands);
1203             break;
1204         default:
1205             break;
1206     }
1207 }
1208 #endif
1209 
1210 static void hci_initializing_next_state(void){
1211     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1212 }
1213 
1214 // assumption: hci_can_send_command_packet_now() == true
1215 static void hci_initializing_run(void){
1216     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1217     switch (hci_stack->substate){
1218         case HCI_INIT_SEND_RESET:
1219             hci_state_reset();
1220 
1221 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1222             // prepare reset if command complete not received in 100ms
1223             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1224             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1225             btstack_run_loop_add_timer(&hci_stack->timeout);
1226 #endif
1227             // send command
1228             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1229             hci_send_cmd(&hci_reset);
1230             break;
1231         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1232             hci_send_cmd(&hci_read_local_version_information);
1233             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1234             break;
1235         case HCI_INIT_SEND_READ_LOCAL_NAME:
1236             hci_send_cmd(&hci_read_local_name);
1237             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1238             break;
1239 
1240 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1241         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1242             hci_state_reset();
1243             // prepare reset if command complete not received in 100ms
1244             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1245             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1246             btstack_run_loop_add_timer(&hci_stack->timeout);
1247             // send command
1248             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1249             hci_send_cmd(&hci_reset);
1250             break;
1251         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1252             hci_state_reset();
1253             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1254             hci_send_cmd(&hci_reset);
1255             break;
1256         case HCI_INIT_SEND_BAUD_CHANGE: {
1257             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1258             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1259             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1260             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1261             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1262             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1263             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1264             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1265                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1266                 btstack_run_loop_add_timer(&hci_stack->timeout);
1267             }
1268             break;
1269         }
1270         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1271             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1272             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1273             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1274             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1275             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1276             break;
1277         }
1278         case HCI_INIT_CUSTOM_INIT:
1279             // Custom initialization
1280             if (hci_stack->chipset && hci_stack->chipset->next_command){
1281                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1282                 int send_cmd = 0;
1283                 switch (hci_stack->chipset_result){
1284                     case BTSTACK_CHIPSET_VALID_COMMAND:
1285                         send_cmd = 1;
1286                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1287                         break;
1288                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1289                         send_cmd = 1;
1290                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1291                         log_info("CSR Warm Boot");
1292                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1293                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1294                         btstack_run_loop_add_timer(&hci_stack->timeout);
1295                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1296                             && hci_stack->config
1297                             && hci_stack->chipset
1298                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1299                             && hci_stack->hci_transport->set_baudrate
1300                             && hci_transport_uart_get_main_baud_rate()){
1301                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1302                         } else {
1303                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1304                         }
1305                         break;
1306                     default:
1307                         break;
1308                 }
1309 
1310                 if (send_cmd){
1311                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1312                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1313                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1314                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1315                     break;
1316                 }
1317                 log_info("Init script done");
1318 
1319                 // Init script download on Broadcom chipsets causes:
1320                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1321                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1322                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1323 
1324                     // - baud rate to reset, restore UART baud rate if needed
1325                     int need_baud_change = hci_stack->config
1326                         && hci_stack->chipset
1327                         && hci_stack->chipset->set_baudrate_command
1328                         && hci_stack->hci_transport->set_baudrate
1329                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1330                     if (need_baud_change) {
1331                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1332                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1333                         hci_stack->hci_transport->set_baudrate(baud_rate);
1334                     }
1335 
1336                     uint16_t bcm_delay_ms = 300;
1337                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1338                     //   -> Work around: wait here.
1339                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1340                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1341                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1342                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1343                     btstack_run_loop_add_timer(&hci_stack->timeout);
1344                     break;
1345                 }
1346             }
1347             // otherwise continue
1348             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1349             hci_send_cmd(&hci_read_local_supported_commands);
1350             break;
1351         case HCI_INIT_SET_BD_ADDR:
1352             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1353             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1354             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1355             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1356             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1357             break;
1358 #endif
1359 
1360         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1361             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1362             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1363             hci_send_cmd(&hci_read_local_supported_commands);
1364             break;
1365         case HCI_INIT_READ_BD_ADDR:
1366             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1367             hci_send_cmd(&hci_read_bd_addr);
1368             break;
1369         case HCI_INIT_READ_BUFFER_SIZE:
1370             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1371             hci_send_cmd(&hci_read_buffer_size);
1372             break;
1373         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1374             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1375             hci_send_cmd(&hci_read_local_supported_features);
1376             break;
1377 
1378 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1379         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1380             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1381             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1382             break;
1383         case HCI_INIT_HOST_BUFFER_SIZE:
1384             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1385             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1386                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1387             break;
1388 #endif
1389 
1390         case HCI_INIT_SET_EVENT_MASK:
1391             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1392             if (hci_le_supported()){
1393                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1394             } else {
1395                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1396                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1397             }
1398             break;
1399 
1400 #ifdef ENABLE_CLASSIC
1401         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1403             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1404             break;
1405         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1407             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1408             break;
1409         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1410             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1411             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1412             break;
1413         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1414             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1415             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1416             break;
1417         case HCI_INIT_WRITE_LOCAL_NAME: {
1418             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1419             hci_reserve_packet_buffer();
1420             uint8_t * packet = hci_stack->hci_packet_buffer;
1421             // construct HCI Command and send
1422             uint16_t opcode = hci_write_local_name.opcode;
1423             hci_stack->last_cmd_opcode = opcode;
1424             packet[0] = opcode & 0xff;
1425             packet[1] = opcode >> 8;
1426             packet[2] = DEVICE_NAME_LEN;
1427             memset(&packet[3], 0, DEVICE_NAME_LEN);
1428             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1429             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1430             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1431             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1432             // expand '00:00:00:00:00:00' in name with bd_addr
1433             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1434             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1435             break;
1436         }
1437         case HCI_INIT_WRITE_EIR_DATA: {
1438             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1439             hci_reserve_packet_buffer();
1440             uint8_t * packet = hci_stack->hci_packet_buffer;
1441             // construct HCI Command in-place and send
1442             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1443             hci_stack->last_cmd_opcode = opcode;
1444             uint16_t offset = 0;
1445             packet[offset++] = opcode & 0xff;
1446             packet[offset++] = opcode >> 8;
1447             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1448             packet[offset++] = 0;  // FEC not required
1449             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1450             if (hci_stack->eir_data){
1451                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1452                 ad_context_t context;
1453                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1454                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1455                     uint8_t size        = ad_iterator_get_data_len(&context);
1456                     const uint8_t *data = ad_iterator_get_data(&context);
1457                     // copy item
1458                     packet[offset++] = size + 1;
1459                     packet[offset++] = data_type;
1460                     memcpy(&packet[offset], data, size);
1461                     // update name item
1462                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1463                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1464                     }
1465                     offset += size;
1466                 }
1467             } else {
1468                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1469                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1470                 packet[offset++] = bytes_to_copy + 1;
1471                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1472                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1473                 // expand '00:00:00:00:00:00' in name with bd_addr
1474                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1475             }
1476             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1477             break;
1478         }
1479         case HCI_INIT_WRITE_INQUIRY_MODE:
1480             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1481             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1482             break;
1483         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1484             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1485 			hci_stack->secure_connections_active = true;
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1487             break;
1488         case HCI_INIT_WRITE_SCAN_ENABLE:
1489             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1490             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1491             break;
1492         // only sent if ENABLE_SCO_OVER_HCI is defined
1493         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1494             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1495             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1496             break;
1497         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1498             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1499             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1500             break;
1501         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1502         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1503             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1504 #ifdef ENABLE_SCO_OVER_HCI
1505             log_info("BCM: Route SCO data via HCI transport");
1506             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1507 #endif
1508 #ifdef ENABLE_SCO_OVER_PCM
1509             log_info("BCM: Route SCO data via PCM interface");
1510             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 4, 0, 1, 1);
1511 #endif
1512             break;
1513 
1514 #endif
1515 #ifdef ENABLE_BLE
1516         // LE INIT
1517         case HCI_INIT_LE_READ_BUFFER_SIZE:
1518             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1519             hci_send_cmd(&hci_le_read_buffer_size);
1520             break;
1521         case HCI_INIT_LE_SET_EVENT_MASK:
1522             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1523             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1524             break;
1525         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1526             // LE Supported Host = 1, Simultaneous Host = 0
1527             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1528             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1529             break;
1530 #endif
1531 
1532 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1533         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1534             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1535             hci_send_cmd(&hci_le_read_maximum_data_length);
1536             break;
1537         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1538             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1539             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1540             break;
1541 #endif
1542 
1543 #ifdef ENABLE_LE_CENTRAL
1544         case HCI_INIT_READ_WHITE_LIST_SIZE:
1545             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1546             hci_send_cmd(&hci_le_read_white_list_size);
1547             break;
1548         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1549             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1550             hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
1551             break;
1552 #endif
1553         default:
1554             return;
1555     }
1556 }
1557 
1558 static void hci_init_done(void){
1559     // done. tell the app
1560     log_info("hci_init_done -> HCI_STATE_WORKING");
1561     hci_stack->state = HCI_STATE_WORKING;
1562     hci_emit_state();
1563     hci_run();
1564 }
1565 
1566 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1567     bool command_completed = false;
1568     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1569         uint16_t opcode = little_endian_read_16(packet,3);
1570         if (opcode == hci_stack->last_cmd_opcode){
1571             command_completed = true;
1572             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1573         } else {
1574             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1575         }
1576     }
1577 
1578     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1579         uint8_t  status = packet[2];
1580         uint16_t opcode = little_endian_read_16(packet,4);
1581         if (opcode == hci_stack->last_cmd_opcode){
1582             if (status){
1583                 command_completed = true;
1584                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1585             } else {
1586                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1587             }
1588         } else {
1589             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1590         }
1591     }
1592 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1593     // Vendor == CSR
1594     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1595         // TODO: track actual command
1596         command_completed = true;
1597     }
1598 
1599     // Vendor == Toshiba
1600     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1601         // TODO: track actual command
1602         command_completed = true;
1603         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1604         hci_stack->num_cmd_packets = 1;
1605     }
1606 #endif
1607 
1608     return command_completed;
1609 }
1610 
1611 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1612 
1613     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1614 
1615     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1616 
1617 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1618 
1619     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1620     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1621     //
1622     // HCI Reset
1623     // Timeout 100 ms
1624     // HCI Reset
1625     // Command Complete Reset
1626     // HCI Read Local Version Information
1627     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1628     // hang...
1629     //
1630     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1631     if (!command_completed
1632             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1633             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1634 
1635         uint16_t opcode = little_endian_read_16(packet,3);
1636         if (opcode == hci_reset.opcode){
1637             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1638             return;
1639         }
1640     }
1641 
1642     // CSR & H5
1643     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1644     if (!command_completed
1645             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1646             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1647 
1648         uint16_t opcode = little_endian_read_16(packet,3);
1649         if (opcode == hci_reset.opcode){
1650             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1651             return;
1652         }
1653     }
1654 
1655     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1656     // fix: Correct substate and behave as command below
1657     if (command_completed){
1658         switch (hci_stack->substate){
1659             case HCI_INIT_SEND_RESET:
1660                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1661                 break;
1662             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1663                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1664                 break;
1665             default:
1666                 break;
1667         }
1668     }
1669 
1670 #endif
1671 
1672     if (!command_completed) return;
1673 
1674     bool need_baud_change = false;
1675     bool need_addr_change = false;
1676 
1677 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1678     need_baud_change = hci_stack->config
1679                         && hci_stack->chipset
1680                         && hci_stack->chipset->set_baudrate_command
1681                         && hci_stack->hci_transport->set_baudrate
1682                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1683 
1684     need_addr_change = hci_stack->custom_bd_addr_set
1685                         && hci_stack->chipset
1686                         && hci_stack->chipset->set_bd_addr_command;
1687 #endif
1688 
1689     switch(hci_stack->substate){
1690 
1691 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1692         case HCI_INIT_SEND_RESET:
1693             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1694             // fix: just correct substate and behave as command below
1695             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1696             btstack_run_loop_remove_timer(&hci_stack->timeout);
1697             break;
1698         case HCI_INIT_W4_SEND_RESET:
1699             btstack_run_loop_remove_timer(&hci_stack->timeout);
1700             break;
1701         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1702             log_info("Received local name, need baud change %d", (int) need_baud_change);
1703             if (need_baud_change){
1704                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1705                 return;
1706             }
1707             // skip baud change
1708             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1709             return;
1710         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1711             // for STLC2500D, baud rate change already happened.
1712             // for others, baud rate gets changed now
1713             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1714                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1715                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1716                 hci_stack->hci_transport->set_baudrate(baud_rate);
1717             }
1718             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1719             return;
1720         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1721             btstack_run_loop_remove_timer(&hci_stack->timeout);
1722             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1723             return;
1724         case HCI_INIT_W4_CUSTOM_INIT:
1725             // repeat custom init
1726             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1727             return;
1728 #else
1729         case HCI_INIT_W4_SEND_RESET:
1730             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1731             return ;
1732 #endif
1733 
1734         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1735             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1736               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1737                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1738                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1739                 return;
1740             }
1741             if (need_addr_change){
1742                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1743                 return;
1744             }
1745             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1746             return;
1747 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1748         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1749             if (need_baud_change){
1750                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1751                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1752                 hci_stack->hci_transport->set_baudrate(baud_rate);
1753             }
1754             if (need_addr_change){
1755                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1756                 return;
1757             }
1758             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1759             return;
1760         case HCI_INIT_W4_SET_BD_ADDR:
1761             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1762             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1763             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1764                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1765                 return;
1766             }
1767             // skipping st warm boot
1768             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1769             return;
1770         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1771             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1772             return;
1773 #endif
1774         case HCI_INIT_W4_READ_BD_ADDR:
1775             // only read buffer size if supported
1776             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1777                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1778                 return;
1779             }
1780             // skipping read buffer size
1781             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1782             return;
1783         case HCI_INIT_W4_SET_EVENT_MASK:
1784             // skip Classic init commands for LE only chipsets
1785             if (!hci_classic_supported()){
1786 #ifdef ENABLE_BLE
1787                 if (hci_le_supported()){
1788                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1789                     return;
1790                 }
1791 #endif
1792                 log_error("Neither BR/EDR nor LE supported");
1793                 hci_init_done();
1794                 return;
1795             }
1796             if (!gap_ssp_supported()){
1797                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1798                 return;
1799             }
1800             break;
1801 #ifdef ENABLE_BLE
1802         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1803             // skip write le host if not supported (e.g. on LE only EM9301)
1804             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1805             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1806             return;
1807 
1808 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1809         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1810             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1811             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1812                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1813                 return;
1814             }
1815             // explicit fall through to reduce repetitions
1816 
1817 #ifdef ENABLE_LE_CENTRAL
1818             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1819 #else
1820             hci_init_done();
1821 #endif
1822             return;
1823 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1824 
1825 #endif  /* ENABLE_BLE */
1826 
1827         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1828             // skip write secure connections host support if not supported or disabled
1829             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1830                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1831                 return;
1832             }
1833             break;
1834 
1835 #ifdef ENABLE_SCO_OVER_HCI
1836         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1837             // skip write synchronous flow control if not supported
1838             if (hci_stack->local_supported_commands[0] & 0x04) break;
1839             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1840 
1841             /* fall through */
1842 
1843         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1844             // skip write default erroneous data reporting if not supported
1845             if (hci_stack->local_supported_commands[0] & 0x08) break;
1846             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1847 
1848             /* fall through */
1849 
1850         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1851             // skip bcm set sco pcm config on non-Broadcom chipsets
1852             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1853             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1854 
1855             /* fall through */
1856 
1857         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1858             if (!hci_le_supported()){
1859                 // SKIP LE init for Classic only configuration
1860                 hci_init_done();
1861                 return;
1862             }
1863             break;
1864 
1865 #else /* !ENABLE_SCO_OVER_HCI */
1866 
1867         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1868 #ifdef ENABLE_SCO_OVER_PCM
1869             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1870                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1871                 return;
1872             }
1873 #endif
1874             /* fall through */
1875 
1876         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1877 #ifdef ENABLE_BLE
1878             if (hci_le_supported()){
1879                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1880                 return;
1881             }
1882 #endif
1883             // SKIP LE init for Classic only configuration
1884             hci_init_done();
1885             return;
1886 #endif /* ENABLE_SCO_OVER_HCI */
1887 
1888 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1889 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1890         // Response to command before init done state -> init done
1891         case (HCI_INIT_DONE-1):
1892             hci_init_done();
1893             return;
1894 #endif
1895 
1896         default:
1897             break;
1898     }
1899     hci_initializing_next_state();
1900 }
1901 
1902 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1903     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1904     bd_addr_t bd_address;
1905     (void)memcpy(&bd_address, conn->address, 6);
1906 
1907 #ifdef ENABLE_CLASSIC
1908     // cache needed data
1909     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1910 #endif
1911 
1912     // connection failed, remove entry
1913     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1914     btstack_memory_hci_connection_free( conn );
1915 
1916 #ifdef ENABLE_CLASSIC
1917     // notify client if dedicated bonding
1918     if (notify_dedicated_bonding_failed){
1919         log_info("hci notify_dedicated_bonding_failed");
1920         hci_emit_dedicated_bonding_result(bd_address, status);
1921     }
1922 
1923     // if authentication error, also delete link key
1924     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1925         gap_drop_link_key_for_bd_addr(bd_address);
1926     }
1927 #else
1928     UNUSED(status);
1929 #endif
1930 }
1931 
1932 #ifdef ENABLE_CLASSIC
1933 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1934     // SSP Controller
1935     if (features[6] & (1 << 3)){
1936         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1937     }
1938     // eSCO
1939     if (features[3] & (1<<7)){
1940         conn->remote_supported_features[0] |= 1;
1941     }
1942     // Extended features
1943     if (features[7] & (1<<7)){
1944         conn->remote_supported_features[0] |= 2;
1945     }
1946 }
1947 
1948 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1949     // SSP Host
1950     if (features[0] & (1 << 0)){
1951         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1952     }
1953     // SC Host
1954     if (features[0] & (1 << 3)){
1955         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1956     }
1957 }
1958 
1959 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1960     // SC Controller
1961     if (features[1] & (1 << 0)){
1962         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1963     }
1964 }
1965 
1966 static void hci_handle_remote_features_received(hci_connection_t * conn){
1967     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1968     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1969     if (conn->bonding_flags & BONDING_DEDICATED){
1970         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1971     }
1972 }
1973 #endif
1974 
1975 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1976     // handle BT initialization
1977     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1978         hci_initializing_event_handler(packet, size);
1979     }
1980 
1981     // help with BT sleep
1982     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1983         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1984         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1985         hci_initializing_next_state();
1986     }
1987 }
1988 
1989 #ifdef ENABLE_CLASSIC
1990 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1991     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1992     conn->encryption_key_size = encryption_key_size;
1993 
1994     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1995         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1996         return;
1997     }
1998 
1999     // Request Authentication if not already done
2000     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2001     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2002 }
2003 #endif
2004 
2005 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2006     UNUSED(size);
2007 
2008     uint16_t manufacturer;
2009 #ifdef ENABLE_CLASSIC
2010     hci_con_handle_t handle;
2011     hci_connection_t * conn;
2012     uint8_t status;
2013 #endif
2014     // get num cmd packets - limit to 1 to reduce complexity
2015     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2016 
2017     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2018     switch (opcode){
2019         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2020             if (packet[5]) break;
2021             // terminate, name 248 chars
2022             packet[6+248] = 0;
2023             log_info("local name: %s", &packet[6]);
2024             break;
2025         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2026             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2027             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2028                 uint16_t acl_len = little_endian_read_16(packet, 6);
2029                 uint16_t sco_len = packet[8];
2030 
2031                 // determine usable ACL/SCO payload size
2032                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2033                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2034 
2035                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2036                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2037 
2038                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2039                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2040                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2041             }
2042             break;
2043         case HCI_OPCODE_HCI_READ_RSSI:
2044             if (packet[5] == ERROR_CODE_SUCCESS){
2045                 uint8_t event[5];
2046                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2047                 event[1] = 3;
2048                 (void)memcpy(&event[2], &packet[6], 3);
2049                 hci_emit_event(event, sizeof(event), 1);
2050             }
2051             break;
2052 #ifdef ENABLE_BLE
2053         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2054             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2055             hci_stack->le_acl_packets_total_num = packet[8];
2056             // determine usable ACL payload size
2057             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2058                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2059             }
2060             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2061             break;
2062 #endif
2063 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2064         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2065             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2066             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2067             log_info("hci_le_read_maximum_data_length: tx octets %u, tx time %u us", hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
2068             break;
2069 #endif
2070 #ifdef ENABLE_LE_CENTRAL
2071         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2072             hci_stack->le_whitelist_capacity = packet[6];
2073             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2074             break;
2075 #endif
2076         case HCI_OPCODE_HCI_READ_BD_ADDR:
2077             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2078             log_info("Local Address, Status: 0x%02x: Addr: %s", packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2079 #ifdef ENABLE_CLASSIC
2080             if (hci_stack->link_key_db){
2081                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2082             }
2083 #endif
2084             break;
2085 #ifdef ENABLE_CLASSIC
2086         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2087             hci_emit_discoverable_enabled(hci_stack->discoverable);
2088             break;
2089         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2090             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2091                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2092                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2093                 hci_emit_event(event, sizeof(event), 1);
2094             }
2095             break;
2096 #endif
2097         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2098             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2099 
2100 #ifdef ENABLE_CLASSIC
2101             // determine usable ACL packet types based on host buffer size and supported features
2102             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2103             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2104 #endif
2105             // Classic/LE
2106             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2107             break;
2108         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2109             manufacturer = little_endian_read_16(packet, 10);
2110             // map Cypress to Broadcom
2111             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2112                 log_info("Treat Cypress as Broadcom");
2113                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2114                 little_endian_store_16(packet, 10, manufacturer);
2115             }
2116             hci_stack->manufacturer = manufacturer;
2117             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2118             break;
2119         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2120             hci_stack->local_supported_commands[0] =
2121                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2122                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2123                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2124                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2125                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2126                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2127                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2128                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2129             hci_stack->local_supported_commands[1] =
2130                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2131                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2132                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u);   // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2133             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2134             break;
2135 #ifdef ENABLE_CLASSIC
2136         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2137             if (packet[5]) return;
2138             hci_stack->synchronous_flow_control_enabled = 1;
2139             break;
2140         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2141             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2142             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2143             conn   = hci_connection_for_handle(handle);
2144             if (conn != NULL) {
2145                 uint8_t key_size = 0;
2146                 if (status == 0){
2147                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2148                     log_info("Handle %04x key Size: %u", handle, key_size);
2149                 } else {
2150                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2151                 }
2152                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2153             }
2154             break;
2155 #endif
2156         default:
2157             break;
2158     }
2159 }
2160 
2161 #ifdef ENABLE_BLE
2162 static void event_handle_le_connection_complete(const uint8_t * packet){
2163 	bd_addr_t addr;
2164 	bd_addr_type_t addr_type;
2165 	hci_connection_t * conn;
2166 
2167 	// Connection management
2168 	reverse_bd_addr(&packet[8], addr);
2169 	addr_type = (bd_addr_type_t)packet[7];
2170 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2171 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2172 
2173 #ifdef ENABLE_LE_CENTRAL
2174 	// handle error: error is reported only to the initiator -> outgoing connection
2175 	if (packet[3]){
2176 
2177 		// handle cancelled outgoing connection
2178 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2179 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2180 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2181 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2182 			// whitelist connect
2183 			if (hci_is_le_connection_type(addr_type)){
2184 				hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2185 				hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2186 			}
2187 			// get outgoing connection conn struct for direct connect
2188 			conn = gap_get_outgoing_connection();
2189 		}
2190 
2191 		// outgoing le connection establishment is done
2192 		if (conn){
2193 			// remove entry
2194 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2195 			btstack_memory_hci_connection_free( conn );
2196 		}
2197 		return;
2198 	}
2199 #endif
2200 
2201 	// on success, both hosts receive connection complete event
2202 	if (packet[6] == HCI_ROLE_MASTER){
2203 #ifdef ENABLE_LE_CENTRAL
2204 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2205 		// note: no hci_connection_t object exists yet for connect with whitelist
2206 		if (hci_is_le_connection_type(addr_type)){
2207 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2208 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2209 		}
2210 #endif
2211 	} else {
2212 #ifdef ENABLE_LE_PERIPHERAL
2213 		// if we're slave, it was an incoming connection, advertisements have stopped
2214 		hci_stack->le_advertisements_active = false;
2215 #endif
2216 	}
2217 
2218 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2219 	if (!conn){
2220 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2221 	}
2222 
2223 	// no memory, sorry.
2224 	if (!conn){
2225 		return;
2226 	}
2227 
2228 	conn->state = OPEN;
2229 	conn->role  = packet[6];
2230 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2231 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2232 
2233 #ifdef ENABLE_LE_PERIPHERAL
2234 	if (packet[6] == HCI_ROLE_SLAVE){
2235 		hci_update_advertisements_enabled_for_current_roles();
2236 	}
2237 #endif
2238 
2239     // init unenhanced att bearer mtu
2240     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2241     conn->att_connection.mtu_exchanged = false;
2242 
2243     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2244 
2245 	// restart timer
2246 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2247 	// btstack_run_loop_add_timer(&conn->timeout);
2248 
2249 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2250 
2251 	hci_emit_nr_connections_changed();
2252 }
2253 #endif
2254 
2255 static void event_handler(uint8_t *packet, uint16_t size){
2256 
2257     uint16_t event_length = packet[1];
2258 
2259     // assert packet is complete
2260     if (size != (event_length + 2u)){
2261         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2262         return;
2263     }
2264 
2265     bd_addr_type_t addr_type;
2266     hci_con_handle_t handle;
2267     hci_connection_t * conn;
2268     int i;
2269     int create_connection_cmd;
2270 
2271 #ifdef ENABLE_CLASSIC
2272     uint8_t link_type;
2273     bd_addr_t addr;
2274 #endif
2275 
2276     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2277 
2278     switch (hci_event_packet_get_type(packet)) {
2279 
2280         case HCI_EVENT_COMMAND_COMPLETE:
2281             handle_command_complete_event(packet, size);
2282             break;
2283 
2284         case HCI_EVENT_COMMAND_STATUS:
2285             // get num cmd packets - limit to 1 to reduce complexity
2286             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2287 
2288             // check command status to detected failed outgoing connections
2289             create_connection_cmd = 0;
2290 #ifdef ENABLE_CLASSIC
2291             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2292                 create_connection_cmd = 1;
2293             }
2294 #endif
2295 #ifdef ENABLE_LE_CENTRAL
2296             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2297                 create_connection_cmd = 1;
2298             }
2299 #endif
2300             if (create_connection_cmd) {
2301                 uint8_t status = hci_event_command_status_get_status(packet);
2302                 addr_type = hci_stack->outgoing_addr_type;
2303                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2304                 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);
2305 
2306                 // reset outgoing address info
2307                 memset(hci_stack->outgoing_addr, 0, 6);
2308                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2309 
2310                 // on error
2311                 if (status != ERROR_CODE_SUCCESS){
2312 #ifdef ENABLE_LE_CENTRAL
2313                     if (hci_is_le_connection_type(addr_type)){
2314                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2315                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2316                     }
2317 #endif
2318                     // error => outgoing connection failed
2319                     if (conn != NULL){
2320                         hci_handle_connection_failed(conn, status);
2321                     }
2322                 }
2323             }
2324             break;
2325 
2326         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2327             if (size < 3) return;
2328             uint16_t num_handles = packet[2];
2329             if (size != (3u + num_handles * 4u)) return;
2330             uint16_t offset = 3;
2331             for (i=0; i<num_handles;i++){
2332                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2333                 offset += 2u;
2334                 uint16_t num_packets = little_endian_read_16(packet, offset);
2335                 offset += 2u;
2336 
2337                 conn = hci_connection_for_handle(handle);
2338                 if (!conn){
2339                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2340                     continue;
2341                 }
2342 
2343                 if (conn->num_packets_sent >= num_packets){
2344                     conn->num_packets_sent -= num_packets;
2345                 } else {
2346                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2347                     conn->num_packets_sent = 0;
2348                 }
2349                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2350 
2351 #ifdef ENABLE_CLASSIC
2352                 // For SCO, we do the can_send_now_check here
2353                 hci_notify_if_sco_can_send_now();
2354 #endif
2355             }
2356             break;
2357         }
2358 
2359 #ifdef ENABLE_CLASSIC
2360         case HCI_EVENT_INQUIRY_COMPLETE:
2361             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2362                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2363                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2364                 hci_emit_event(event, sizeof(event), 1);
2365             }
2366             break;
2367         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2368             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2369                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2370             }
2371             break;
2372         case HCI_EVENT_CONNECTION_REQUEST:
2373             reverse_bd_addr(&packet[2], addr);
2374             if (hci_stack->gap_classic_accept_callback != NULL){
2375                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2376                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2377                     bd_addr_copy(hci_stack->decline_addr, addr);
2378                     break;
2379                 }
2380             }
2381 
2382             // TODO: eval COD 8-10
2383             link_type = packet[11];
2384             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2385             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2386             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2387             if (!conn) {
2388                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2389             }
2390             if (!conn) {
2391                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2392                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2393                 bd_addr_copy(hci_stack->decline_addr, addr);
2394                 break;
2395             }
2396             conn->role  = HCI_ROLE_SLAVE;
2397             conn->state = RECEIVED_CONNECTION_REQUEST;
2398             // store info about eSCO
2399             if (link_type == 0x02){
2400                 conn->remote_supported_features[0] |= 1;
2401             }
2402             hci_run();
2403             break;
2404 
2405         case HCI_EVENT_CONNECTION_COMPLETE:
2406             // Connection management
2407             reverse_bd_addr(&packet[5], addr);
2408             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2409             addr_type = BD_ADDR_TYPE_ACL;
2410             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2411             if (conn) {
2412                 if (!packet[2]){
2413                     conn->state = OPEN;
2414                     conn->con_handle = little_endian_read_16(packet, 3);
2415 
2416                     // queue get remote feature
2417                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2418 
2419                     // queue set supervision timeout if we're master
2420                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2421                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2422                     }
2423 
2424                     // restart timer
2425                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2426                     btstack_run_loop_add_timer(&conn->timeout);
2427 
2428                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2429 
2430                     hci_emit_nr_connections_changed();
2431                 } else {
2432                     // connection failed
2433                     hci_handle_connection_failed(conn, packet[2]);
2434                 }
2435             }
2436             break;
2437 
2438         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2439             reverse_bd_addr(&packet[5], addr);
2440             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2441             if (packet[2]){
2442                 // connection failed
2443                 break;
2444             }
2445             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2446             if (!conn) {
2447                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2448             }
2449             if (!conn) {
2450                 break;
2451             }
2452             conn->state = OPEN;
2453             conn->con_handle = little_endian_read_16(packet, 3);
2454 
2455 #ifdef ENABLE_SCO_OVER_HCI
2456             // update SCO
2457             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2458                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2459             }
2460             // trigger can send now
2461             if (hci_have_usb_transport()){
2462                 hci_stack->sco_can_send_now = 1;
2463             }
2464 #endif
2465             break;
2466 
2467         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2468             handle = little_endian_read_16(packet, 3);
2469             conn = hci_connection_for_handle(handle);
2470             if (!conn) break;
2471             if (!packet[2]){
2472                 const uint8_t * features = &packet[5];
2473                 hci_handle_remote_features_page_0(conn, features);
2474 
2475                 // read extended features if possible
2476                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2477                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2478                     break;
2479                 }
2480             }
2481             hci_handle_remote_features_received(conn);
2482             break;
2483 
2484         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2485             handle = little_endian_read_16(packet, 3);
2486             conn = hci_connection_for_handle(handle);
2487             if (!conn) break;
2488             // status = ok, page = 1
2489             if (!packet[2]) {
2490                 uint8_t page_number = packet[5];
2491                 uint8_t maximum_page_number = packet[6];
2492                 const uint8_t * features = &packet[7];
2493                 bool done = false;
2494                 switch (page_number){
2495                     case 1:
2496                         hci_handle_remote_features_page_1(conn, features);
2497                         if (maximum_page_number >= 2){
2498                             // get Secure Connections (Controller) from Page 2 if available
2499                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2500                         } else {
2501                             // otherwise, assume SC (Controller) == SC (Host)
2502                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2503                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2504                             }
2505                             done = true;
2506                         }
2507                         break;
2508                     case 2:
2509                         hci_handle_remote_features_page_2(conn, features);
2510                         done = true;
2511                         break;
2512                     default:
2513                         break;
2514                 }
2515                 if (!done) break;
2516             }
2517             hci_handle_remote_features_received(conn);
2518             break;
2519 
2520         case HCI_EVENT_LINK_KEY_REQUEST:
2521             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2522             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2523             // request handled by hci_run()
2524             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2525             break;
2526 
2527         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2528             reverse_bd_addr(&packet[2], addr);
2529             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2530             if (!conn) break;
2531             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2532             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2533             // Change Connection Encryption keeps link key type
2534             if (link_key_type != CHANGED_COMBINATION_KEY){
2535                 conn->link_key_type = link_key_type;
2536             }
2537             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2538             // still forward event to allow dismiss of pairing dialog
2539             break;
2540         }
2541 
2542         case HCI_EVENT_PIN_CODE_REQUEST:
2543             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2544             // non-bondable mode: pin code negative reply will be sent
2545             if (!hci_stack->bondable){
2546                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2547                 hci_run();
2548                 return;
2549             }
2550             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2551             if (!hci_stack->link_key_db) break;
2552             hci_event_pin_code_request_get_bd_addr(packet, addr);
2553             hci_stack->link_key_db->delete_link_key(addr);
2554             break;
2555 
2556         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2557             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2558             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2559             break;
2560 
2561         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2562             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2563             if (!hci_stack->ssp_auto_accept) break;
2564             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2565             break;
2566 
2567         case HCI_EVENT_USER_PASSKEY_REQUEST:
2568             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2569             if (!hci_stack->ssp_auto_accept) break;
2570             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2571             break;
2572         case HCI_EVENT_MODE_CHANGE:
2573             handle = hci_event_mode_change_get_handle(packet);
2574             conn = hci_connection_for_handle(handle);
2575             if (!conn) break;
2576             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2577             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2578             break;
2579 #endif
2580 
2581         case HCI_EVENT_ENCRYPTION_CHANGE:
2582             handle = hci_event_encryption_change_get_connection_handle(packet);
2583             conn = hci_connection_for_handle(handle);
2584             if (!conn) break;
2585             if (hci_event_encryption_change_get_status(packet) == 0u) {
2586                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2587                 if (encryption_enabled){
2588                     if (hci_is_le_connection(conn)){
2589                         // For LE, we accept connection as encrypted
2590                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2591                     }
2592 #ifdef ENABLE_CLASSIC
2593                     else {
2594                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2595                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2596                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2597                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2598                             log_info("SC during pairing, but only E0 now -> abort");
2599                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2600                             break;
2601                         }
2602 
2603                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2604                         if (connected_uses_aes_ccm){
2605                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2606                         }
2607 
2608                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2609                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2610                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2611                         } else {
2612                             // if not, pretend everything is perfect
2613                             hci_handle_read_encryption_key_size_complete(conn, 16);
2614                         }
2615                     }
2616 #endif
2617                 } else {
2618                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2619                 }
2620             }
2621 
2622             break;
2623 
2624 #ifdef ENABLE_CLASSIC
2625         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2626             handle = hci_event_authentication_complete_get_connection_handle(packet);
2627             conn = hci_connection_for_handle(handle);
2628             if (!conn) break;
2629 
2630             // ignore authentication event if we didn't request it
2631             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2632 
2633             // dedicated bonding: send result and disconnect
2634             if (conn->bonding_flags & BONDING_DEDICATED){
2635                 conn->bonding_flags &= ~BONDING_DEDICATED;
2636                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2637                 conn->bonding_status = packet[2];
2638                 break;
2639             }
2640 
2641             // authenticated only if auth status == 0
2642             if (hci_event_authentication_complete_get_status(packet) == 0){
2643                 // authenticated
2644                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2645 
2646                 // If link key sufficient for requested security and not already encrypted, start encryption
2647                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2648                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2649                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2650                     break;
2651                 }
2652             }
2653 
2654             // emit updated security level
2655             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2656             break;
2657 #endif
2658 
2659         // HCI_EVENT_DISCONNECTION_COMPLETE
2660         // has been split, to first notify stack before shutting connection down
2661         // see end of function, too.
2662         case HCI_EVENT_DISCONNECTION_COMPLETE:
2663             if (packet[2]) break;   // status != 0
2664             handle = little_endian_read_16(packet, 3);
2665             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2666             if (hci_stack->acl_fragmentation_total_size > 0u) {
2667                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2668                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2669                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2670                     hci_stack->acl_fragmentation_total_size = 0;
2671                     hci_stack->acl_fragmentation_pos = 0;
2672                     if (release_buffer){
2673                         hci_release_packet_buffer();
2674                     }
2675                 }
2676             }
2677 
2678             conn = hci_connection_for_handle(handle);
2679             if (!conn) break;
2680             // mark connection for shutdown
2681             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2682 
2683             // emit dedicatd bonding event
2684             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2685                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2686             }
2687 
2688 #ifdef ENABLE_BLE
2689 #ifdef ENABLE_LE_PERIPHERAL
2690             // re-enable advertisements for le connections if active
2691             if (hci_is_le_connection(conn)){
2692                 hci_update_advertisements_enabled_for_current_roles();
2693             }
2694 #endif
2695 #endif
2696             break;
2697 
2698         case HCI_EVENT_HARDWARE_ERROR:
2699             log_error("Hardware Error: 0x%02x", packet[2]);
2700             if (hci_stack->hardware_error_callback){
2701                 (*hci_stack->hardware_error_callback)(packet[2]);
2702             } else {
2703                 // if no special requests, just reboot stack
2704                 hci_power_control_off();
2705                 hci_power_control_on();
2706             }
2707             break;
2708 
2709 #ifdef ENABLE_CLASSIC
2710         case HCI_EVENT_ROLE_CHANGE:
2711             if (packet[2]) break;   // status != 0
2712             reverse_bd_addr(&packet[3], addr);
2713             addr_type = BD_ADDR_TYPE_ACL;
2714             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2715             if (!conn) break;
2716             conn->role = packet[9];
2717             break;
2718 #endif
2719 
2720         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2721             // release packet buffer only for asynchronous transport and if there are not further fragements
2722             if (hci_transport_synchronous()) {
2723                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2724                 return; // instead of break: to avoid re-entering hci_run()
2725             }
2726             hci_stack->acl_fragmentation_tx_active = 0;
2727             if (hci_stack->acl_fragmentation_total_size) break;
2728             hci_release_packet_buffer();
2729 
2730             // L2CAP receives this event via the hci_emit_event below
2731 
2732 #ifdef ENABLE_CLASSIC
2733             // For SCO, we do the can_send_now_check here
2734             hci_notify_if_sco_can_send_now();
2735 #endif
2736             break;
2737 
2738 #ifdef ENABLE_CLASSIC
2739         case HCI_EVENT_SCO_CAN_SEND_NOW:
2740             // For SCO, we do the can_send_now_check here
2741             hci_stack->sco_can_send_now = 1;
2742             hci_notify_if_sco_can_send_now();
2743             return;
2744 
2745         // explode inquriy results for easier consumption
2746         case HCI_EVENT_INQUIRY_RESULT:
2747         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2748         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2749             gap_inquiry_explode(packet, size);
2750             break;
2751 #endif
2752 
2753 #ifdef ENABLE_BLE
2754         case HCI_EVENT_LE_META:
2755             switch (packet[2]){
2756 #ifdef ENABLE_LE_CENTRAL
2757                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2758                     // log_info("advertising report received");
2759                     if (!hci_stack->le_scanning_enabled) break;
2760                     le_handle_advertisement_report(packet, size);
2761                     break;
2762 #endif
2763                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2764 					event_handle_le_connection_complete(packet);
2765                     break;
2766 
2767                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2768                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2769                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2770                     conn = hci_connection_for_handle(handle);
2771                     if (!conn) break;
2772                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2773                     break;
2774 
2775                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2776                     // connection
2777                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2778                     conn = hci_connection_for_handle(handle);
2779                     if (conn) {
2780                         // read arguments
2781                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2782                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2783                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2784                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2785 
2786                         // validate against current connection parameter range
2787                         le_connection_parameter_range_t existing_range;
2788                         gap_get_connection_parameter_range(&existing_range);
2789                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2790                         if (update_parameter){
2791                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2792                             conn->le_conn_interval_min = le_conn_interval_min;
2793                             conn->le_conn_interval_max = le_conn_interval_max;
2794                             conn->le_conn_latency = le_conn_latency;
2795                             conn->le_supervision_timeout = le_supervision_timeout;
2796                         } else {
2797                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
2798                         }
2799                     }
2800                     break;
2801 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2802                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2803                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2804                     conn = hci_connection_for_handle(handle);
2805                     if (conn) {
2806                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2807                     }
2808                     break;
2809 #endif
2810                 default:
2811                     break;
2812             }
2813             break;
2814 #endif
2815         case HCI_EVENT_VENDOR_SPECIFIC:
2816             // Vendor specific commands often create vendor specific event instead of num completed packets
2817             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2818             switch (hci_stack->manufacturer){
2819                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2820                     hci_stack->num_cmd_packets = 1;
2821                     break;
2822                 default:
2823                     break;
2824             }
2825             break;
2826         default:
2827             break;
2828     }
2829 
2830     handle_event_for_current_stack_state(packet, size);
2831 
2832     // notify upper stack
2833 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2834 
2835     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2836     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
2837 		handle = little_endian_read_16(packet, 3);
2838 		hci_connection_t * aConn = hci_connection_for_handle(handle);
2839 		// discard connection if app did not trigger a reconnect in the event handler
2840 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2841 			hci_shutdown_connection(aConn);
2842 		}
2843     }
2844 
2845 	// execute main loop
2846 	hci_run();
2847 }
2848 
2849 #ifdef ENABLE_CLASSIC
2850 
2851 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2852 static void sco_schedule_tx(hci_connection_t * conn);
2853 
2854 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2855     log_debug("SCO TX Timeout");
2856     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2857     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2858     if (!conn) return;
2859 
2860     // trigger send
2861     conn->sco_tx_ready = 1;
2862     // extra packet if CVSD but SCO buffer is too short
2863     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2864         conn->sco_tx_ready++;
2865     }
2866     hci_notify_if_sco_can_send_now();
2867 }
2868 
2869 
2870 #define SCO_TX_AFTER_RX_MS (6)
2871 
2872 static void sco_schedule_tx(hci_connection_t * conn){
2873 
2874     uint32_t now = btstack_run_loop_get_time_ms();
2875     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2876     int time_delta_ms = sco_tx_ms - now;
2877 
2878     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2879 
2880     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2881     btstack_run_loop_set_timer(timer, time_delta_ms);
2882     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2883     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2884     btstack_run_loop_add_timer(timer);
2885 }
2886 
2887 static void sco_handler(uint8_t * packet, uint16_t size){
2888     // lookup connection struct
2889     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2890     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2891     if (!conn) return;
2892 
2893     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2894     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2895         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2896             packet[2] = 0x3c;
2897             memmove(&packet[3], &packet[23], 63);
2898             size = 63;
2899         }
2900     }
2901 
2902     if (hci_have_usb_transport()){
2903         // Nothing to do
2904     } else {
2905         // 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);
2906         if (hci_stack->synchronous_flow_control_enabled == 0){
2907             uint32_t now = btstack_run_loop_get_time_ms();
2908 
2909             if (!conn->sco_rx_valid){
2910                 // ignore first 10 packets
2911                 conn->sco_rx_count++;
2912                 // log_debug("sco rx count %u", conn->sco_rx_count);
2913                 if (conn->sco_rx_count == 10) {
2914                     // use first timestamp as is and pretent it just started
2915                     conn->sco_rx_ms = now;
2916                     conn->sco_rx_valid = 1;
2917                     conn->sco_rx_count = 0;
2918                     sco_schedule_tx(conn);
2919                 }
2920             } else {
2921                 // track expected arrival timme
2922                 conn->sco_rx_count++;
2923                 conn->sco_rx_ms += 7;
2924                 int delta = (int32_t) (now - conn->sco_rx_ms);
2925                 if (delta > 0){
2926                     conn->sco_rx_ms++;
2927                 }
2928                 // log_debug("sco rx %u", conn->sco_rx_ms);
2929                 sco_schedule_tx(conn);
2930             }
2931         }
2932     }
2933     // deliver to app
2934     if (hci_stack->sco_packet_handler) {
2935         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2936     }
2937 
2938 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2939     conn->num_packets_completed++;
2940     hci_stack->host_completed_packets = 1;
2941     hci_run();
2942 #endif
2943 }
2944 #endif
2945 
2946 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2947     hci_dump_packet(packet_type, 1, packet, size);
2948     switch (packet_type) {
2949         case HCI_EVENT_PACKET:
2950             event_handler(packet, size);
2951             break;
2952         case HCI_ACL_DATA_PACKET:
2953             acl_handler(packet, size);
2954             break;
2955 #ifdef ENABLE_CLASSIC
2956         case HCI_SCO_DATA_PACKET:
2957             sco_handler(packet, size);
2958             break;
2959 #endif
2960         default:
2961             break;
2962     }
2963 }
2964 
2965 /**
2966  * @brief Add event packet handler.
2967  */
2968 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2969     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2970 }
2971 
2972 
2973 /** Register HCI packet handlers */
2974 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2975     hci_stack->acl_packet_handler = handler;
2976 }
2977 
2978 #ifdef ENABLE_CLASSIC
2979 /**
2980  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2981  */
2982 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2983     hci_stack->sco_packet_handler = handler;
2984 }
2985 #endif
2986 
2987 static void hci_state_reset(void){
2988     // no connections yet
2989     hci_stack->connections = NULL;
2990 
2991     // keep discoverable/connectable as this has been requested by the client(s)
2992     // hci_stack->discoverable = 0;
2993     // hci_stack->connectable = 0;
2994     // hci_stack->bondable = 1;
2995     // hci_stack->own_addr_type = 0;
2996 
2997     // buffer is free
2998     hci_stack->hci_packet_buffer_reserved = 0;
2999 
3000     // no pending cmds
3001     hci_stack->decline_reason = 0;
3002     hci_stack->new_scan_enable_value = 0xff;
3003 
3004     hci_stack->secure_connections_active = false;
3005 
3006     // LE
3007 #ifdef ENABLE_BLE
3008     memset(hci_stack->le_random_address, 0, 6);
3009     hci_stack->le_random_address_set = 0;
3010 #endif
3011 #ifdef ENABLE_LE_CENTRAL
3012     hci_stack->le_scanning_active  = 0;
3013     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3014     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3015     hci_stack->le_whitelist_capacity = 0;
3016 #endif
3017 }
3018 
3019 #ifdef ENABLE_CLASSIC
3020 /**
3021  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3022  */
3023 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3024     // store and open remote device db
3025     hci_stack->link_key_db = link_key_db;
3026     if (hci_stack->link_key_db) {
3027         hci_stack->link_key_db->open();
3028     }
3029 }
3030 #endif
3031 
3032 void hci_init(const hci_transport_t *transport, const void *config){
3033 
3034 #ifdef HAVE_MALLOC
3035     if (!hci_stack) {
3036         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3037     }
3038 #else
3039     hci_stack = &hci_stack_static;
3040 #endif
3041     memset(hci_stack, 0, sizeof(hci_stack_t));
3042 
3043     // reference to use transport layer implementation
3044     hci_stack->hci_transport = transport;
3045 
3046     // reference to used config
3047     hci_stack->config = config;
3048 
3049     // setup pointer for outgoing packet buffer
3050     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3051 
3052     // max acl payload size defined in config.h
3053     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3054 
3055     // register packet handlers with transport
3056     transport->register_packet_handler(&packet_handler);
3057 
3058     hci_stack->state = HCI_STATE_OFF;
3059 
3060     // class of device
3061     hci_stack->class_of_device = 0x007a020c; // Smartphone
3062 
3063     // bondable by default
3064     hci_stack->bondable = 1;
3065 
3066 #ifdef ENABLE_CLASSIC
3067     // classic name
3068     hci_stack->local_name = default_classic_name;
3069 
3070     // Master slave policy
3071     hci_stack->master_slave_policy = 1;
3072 
3073     // Allow Role Switch
3074     hci_stack->allow_role_switch = 1;
3075 
3076     // Default / minimum security level = 2
3077     hci_stack->gap_security_level = LEVEL_2;
3078 
3079     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3080     hci_stack->gap_required_encyrption_key_size = 7;
3081 #endif
3082 
3083     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3084     hci_stack->ssp_enable = 1;
3085     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3086     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3087     hci_stack->ssp_auto_accept = 1;
3088 
3089     // Secure Connections: enable (requires support from Controller)
3090     hci_stack->secure_connections_enable = true;
3091 
3092     // voice setting - signed 16 bit pcm data with CVSD over the air
3093     hci_stack->sco_voice_setting = 0x60;
3094 
3095 #ifdef ENABLE_LE_CENTRAL
3096     // connection parameter to use for outgoing connections
3097     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3098     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3099     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3100     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3101     hci_stack->le_connection_latency      = 4;         // 4
3102     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3103     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3104     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3105 
3106     // default LE Scanning
3107     hci_stack->le_scan_type     =   0x1; // active
3108     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3109     hci_stack->le_scan_window   =  0x30; //  30 ms
3110 #endif
3111 
3112 #ifdef ENABLE_LE_PERIPHERAL
3113     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3114 #endif
3115 
3116     // connection parameter range used to answer connection parameter update requests in l2cap
3117     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3118     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3119     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3120     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3121     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3122     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3123 
3124     hci_state_reset();
3125 }
3126 
3127 void hci_deinit(void){
3128 #ifdef HAVE_MALLOC
3129     if (hci_stack) {
3130         free(hci_stack);
3131     }
3132 #endif
3133     hci_stack = NULL;
3134     disable_l2cap_timeouts = 0;
3135 }
3136 
3137 /**
3138  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3139  */
3140 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3141     hci_stack->chipset = chipset_driver;
3142 
3143     // reset chipset driver - init is also called on power_up
3144     if (hci_stack->chipset && hci_stack->chipset->init){
3145         hci_stack->chipset->init(hci_stack->config);
3146     }
3147 }
3148 
3149 /**
3150  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3151  */
3152 void hci_set_control(const btstack_control_t *hardware_control){
3153     // references to used control implementation
3154     hci_stack->control = hardware_control;
3155     // init with transport config
3156     hardware_control->init(hci_stack->config);
3157 }
3158 
3159 void hci_close(void){
3160     // close remote device db
3161     if (hci_stack->link_key_db) {
3162         hci_stack->link_key_db->close();
3163     }
3164 
3165     btstack_linked_list_iterator_t lit;
3166     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3167     while (btstack_linked_list_iterator_has_next(&lit)){
3168         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3169         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3170         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3171         hci_shutdown_connection(connection);
3172     }
3173 
3174     hci_power_control(HCI_POWER_OFF);
3175 
3176 #ifdef HAVE_MALLOC
3177     free(hci_stack);
3178 #endif
3179     hci_stack = NULL;
3180 }
3181 
3182 #ifdef ENABLE_CLASSIC
3183 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3184     // validate ranage and set
3185     if (encryption_key_size < 7)  return;
3186     if (encryption_key_size > 16) return;
3187     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3188 }
3189 
3190 void gap_set_security_level(gap_security_level_t security_level){
3191     hci_stack->gap_security_level = security_level;
3192 }
3193 
3194 gap_security_level_t gap_get_security_level(void){
3195     return hci_stack->gap_security_level;
3196 }
3197 #endif
3198 
3199 #ifdef ENABLE_CLASSIC
3200 void gap_set_class_of_device(uint32_t class_of_device){
3201     hci_stack->class_of_device = class_of_device;
3202 }
3203 
3204 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3205     hci_stack->default_link_policy_settings = default_link_policy_settings;
3206 }
3207 
3208 void gap_set_allow_role_switch(bool allow_role_switch){
3209     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3210 }
3211 
3212 uint8_t hci_get_allow_role_switch(void){
3213     return  hci_stack->allow_role_switch;
3214 }
3215 
3216 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3217     hci_stack->link_supervision_timeout = link_supervision_timeout;
3218 }
3219 
3220 void hci_disable_l2cap_timeout_check(void){
3221     disable_l2cap_timeouts = 1;
3222 }
3223 #endif
3224 
3225 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3226 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3227 void hci_set_bd_addr(bd_addr_t addr){
3228     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3229     hci_stack->custom_bd_addr_set = 1;
3230 }
3231 #endif
3232 
3233 // State-Module-Driver overview
3234 // state                    module  low-level
3235 // HCI_STATE_OFF             off      close
3236 // HCI_STATE_INITIALIZING,   on       open
3237 // HCI_STATE_WORKING,        on       open
3238 // HCI_STATE_HALTING,        on       open
3239 // HCI_STATE_SLEEPING,    off/sleep   close
3240 // HCI_STATE_FALLING_ASLEEP  on       open
3241 
3242 static int hci_power_control_on(void){
3243 
3244     // power on
3245     int err = 0;
3246     if (hci_stack->control && hci_stack->control->on){
3247         err = (*hci_stack->control->on)();
3248     }
3249     if (err){
3250         log_error( "POWER_ON failed");
3251         hci_emit_hci_open_failed();
3252         return err;
3253     }
3254 
3255     // int chipset driver
3256     if (hci_stack->chipset && hci_stack->chipset->init){
3257         hci_stack->chipset->init(hci_stack->config);
3258     }
3259 
3260     // init transport
3261     if (hci_stack->hci_transport->init){
3262         hci_stack->hci_transport->init(hci_stack->config);
3263     }
3264 
3265     // open transport
3266     err = hci_stack->hci_transport->open();
3267     if (err){
3268         log_error( "HCI_INIT failed, turning Bluetooth off again");
3269         if (hci_stack->control && hci_stack->control->off){
3270             (*hci_stack->control->off)();
3271         }
3272         hci_emit_hci_open_failed();
3273         return err;
3274     }
3275     return 0;
3276 }
3277 
3278 static void hci_power_control_off(void){
3279 
3280     log_info("hci_power_control_off");
3281 
3282     // close low-level device
3283     hci_stack->hci_transport->close();
3284 
3285     log_info("hci_power_control_off - hci_transport closed");
3286 
3287     // power off
3288     if (hci_stack->control && hci_stack->control->off){
3289         (*hci_stack->control->off)();
3290     }
3291 
3292     log_info("hci_power_control_off - control closed");
3293 
3294     hci_stack->state = HCI_STATE_OFF;
3295 }
3296 
3297 static void hci_power_control_sleep(void){
3298 
3299     log_info("hci_power_control_sleep");
3300 
3301 #if 0
3302     // don't close serial port during sleep
3303 
3304     // close low-level device
3305     hci_stack->hci_transport->close(hci_stack->config);
3306 #endif
3307 
3308     // sleep mode
3309     if (hci_stack->control && hci_stack->control->sleep){
3310         (*hci_stack->control->sleep)();
3311     }
3312 
3313     hci_stack->state = HCI_STATE_SLEEPING;
3314 }
3315 
3316 static int hci_power_control_wake(void){
3317 
3318     log_info("hci_power_control_wake");
3319 
3320     // wake on
3321     if (hci_stack->control && hci_stack->control->wake){
3322         (*hci_stack->control->wake)();
3323     }
3324 
3325 #if 0
3326     // open low-level device
3327     int err = hci_stack->hci_transport->open(hci_stack->config);
3328     if (err){
3329         log_error( "HCI_INIT failed, turning Bluetooth off again");
3330         if (hci_stack->control && hci_stack->control->off){
3331             (*hci_stack->control->off)();
3332         }
3333         hci_emit_hci_open_failed();
3334         return err;
3335     }
3336 #endif
3337 
3338     return 0;
3339 }
3340 
3341 static void hci_power_transition_to_initializing(void){
3342     // set up state machine
3343     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3344     hci_stack->hci_packet_buffer_reserved = 0;
3345     hci_stack->state = HCI_STATE_INITIALIZING;
3346     hci_stack->substate = HCI_INIT_SEND_RESET;
3347 }
3348 
3349 int hci_power_control(HCI_POWER_MODE power_mode){
3350 
3351     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3352 
3353     int err = 0;
3354     switch (hci_stack->state){
3355 
3356         case HCI_STATE_OFF:
3357             switch (power_mode){
3358                 case HCI_POWER_ON:
3359                     err = hci_power_control_on();
3360                     if (err) {
3361                         log_error("hci_power_control_on() error %d", err);
3362                         return err;
3363                     }
3364                     hci_power_transition_to_initializing();
3365                     break;
3366                 case HCI_POWER_OFF:
3367                     // do nothing
3368                     break;
3369                 case HCI_POWER_SLEEP:
3370                     // do nothing (with SLEEP == OFF)
3371                     break;
3372                 default:
3373                     btstack_assert(false);
3374                     break;
3375             }
3376             break;
3377 
3378         case HCI_STATE_INITIALIZING:
3379             switch (power_mode){
3380                 case HCI_POWER_ON:
3381                     // do nothing
3382                     break;
3383                 case HCI_POWER_OFF:
3384                     // no connections yet, just turn it off
3385                     hci_power_control_off();
3386                     break;
3387                 case HCI_POWER_SLEEP:
3388                     // no connections yet, just turn it off
3389                     hci_power_control_sleep();
3390                     break;
3391                 default:
3392                     btstack_assert(false);
3393                     break;
3394             }
3395             break;
3396 
3397         case HCI_STATE_WORKING:
3398             switch (power_mode){
3399                 case HCI_POWER_ON:
3400                     // do nothing
3401                     break;
3402                 case HCI_POWER_OFF:
3403                     // see hci_run
3404                     hci_stack->state = HCI_STATE_HALTING;
3405                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3406                     break;
3407                 case HCI_POWER_SLEEP:
3408                     // see hci_run
3409                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3410                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3411                     break;
3412                 default:
3413                     btstack_assert(false);
3414                     break;
3415             }
3416             break;
3417 
3418         case HCI_STATE_HALTING:
3419             switch (power_mode){
3420                 case HCI_POWER_ON:
3421                     hci_power_transition_to_initializing();
3422                     break;
3423                 case HCI_POWER_OFF:
3424                     // do nothing
3425                     break;
3426                 case HCI_POWER_SLEEP:
3427                     // see hci_run
3428                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3429                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3430                     break;
3431                 default:
3432                     btstack_assert(false);
3433                     break;
3434             }
3435             break;
3436 
3437         case HCI_STATE_FALLING_ASLEEP:
3438             switch (power_mode){
3439                 case HCI_POWER_ON:
3440 
3441 #ifdef HAVE_PLATFORM_IPHONE_OS
3442                     // nothing to do, if H4 supports power management
3443                     if (btstack_control_iphone_power_management_enabled()){
3444                         hci_stack->state = HCI_STATE_INITIALIZING;
3445                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3446                         break;
3447                     }
3448 #endif
3449                     hci_power_transition_to_initializing();
3450                     break;
3451                 case HCI_POWER_OFF:
3452                     // see hci_run
3453                     hci_stack->state = HCI_STATE_HALTING;
3454                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3455                     break;
3456                 case HCI_POWER_SLEEP:
3457                     // do nothing
3458                     break;
3459                 default:
3460                     btstack_assert(false);
3461                     break;
3462             }
3463             break;
3464 
3465         case HCI_STATE_SLEEPING:
3466             switch (power_mode){
3467                 case HCI_POWER_ON:
3468 
3469 #ifdef HAVE_PLATFORM_IPHONE_OS
3470                     // nothing to do, if H4 supports power management
3471                     if (btstack_control_iphone_power_management_enabled()){
3472                         hci_stack->state = HCI_STATE_INITIALIZING;
3473                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3474                         hci_update_scan_enable();
3475                         break;
3476                     }
3477 #endif
3478                     err = hci_power_control_wake();
3479                     if (err) return err;
3480                     hci_power_transition_to_initializing();
3481                     break;
3482                 case HCI_POWER_OFF:
3483                     hci_stack->state = HCI_STATE_HALTING;
3484                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3485                     break;
3486                 case HCI_POWER_SLEEP:
3487                     // do nothing
3488                     break;
3489                 default:
3490                     btstack_assert(false);
3491                     break;
3492             }
3493             break;
3494 
3495         default:
3496             btstack_assert(false);
3497             break;
3498     }
3499 
3500     // create internal event
3501 	hci_emit_state();
3502 
3503 	// trigger next/first action
3504 	hci_run();
3505 
3506     return 0;
3507 }
3508 
3509 
3510 #ifdef ENABLE_CLASSIC
3511 
3512 static void hci_update_scan_enable(void){
3513     // 2 = page scan, 1 = inq scan
3514     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3515     hci_run();
3516 }
3517 
3518 void gap_discoverable_control(uint8_t enable){
3519     if (enable) enable = 1; // normalize argument
3520 
3521     if (hci_stack->discoverable == enable){
3522         hci_emit_discoverable_enabled(hci_stack->discoverable);
3523         return;
3524     }
3525 
3526     hci_stack->discoverable = enable;
3527     hci_update_scan_enable();
3528 }
3529 
3530 void gap_connectable_control(uint8_t enable){
3531     if (enable) enable = 1; // normalize argument
3532 
3533     // don't emit event
3534     if (hci_stack->connectable == enable) return;
3535 
3536     hci_stack->connectable = enable;
3537     hci_update_scan_enable();
3538 }
3539 #endif
3540 
3541 void gap_local_bd_addr(bd_addr_t address_buffer){
3542     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3543 }
3544 
3545 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3546 static void hci_host_num_completed_packets(void){
3547 
3548     // create packet manually as arrays are not supported and num_commands should not get reduced
3549     hci_reserve_packet_buffer();
3550     uint8_t * packet = hci_get_outgoing_packet_buffer();
3551 
3552     uint16_t size = 0;
3553     uint16_t num_handles = 0;
3554     packet[size++] = 0x35;
3555     packet[size++] = 0x0c;
3556     size++;  // skip param len
3557     size++;  // skip num handles
3558 
3559     // add { handle, packets } entries
3560     btstack_linked_item_t * it;
3561     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3562         hci_connection_t * connection = (hci_connection_t *) it;
3563         if (connection->num_packets_completed){
3564             little_endian_store_16(packet, size, connection->con_handle);
3565             size += 2;
3566             little_endian_store_16(packet, size, connection->num_packets_completed);
3567             size += 2;
3568             //
3569             num_handles++;
3570             connection->num_packets_completed = 0;
3571         }
3572     }
3573 
3574     packet[2] = size - 3;
3575     packet[3] = num_handles;
3576 
3577     hci_stack->host_completed_packets = 0;
3578 
3579     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3580     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3581 
3582     // release packet buffer for synchronous transport implementations
3583     if (hci_transport_synchronous()){
3584         hci_release_packet_buffer();
3585         hci_emit_transport_packet_sent();
3586     }
3587 }
3588 #endif
3589 
3590 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3591     UNUSED(ds);
3592     hci_stack->substate = HCI_HALTING_CLOSE;
3593     // allow packet handlers to defer final shutdown
3594     hci_emit_state();
3595     hci_run();
3596 }
3597 
3598 static bool hci_run_acl_fragments(void){
3599     if (hci_stack->acl_fragmentation_total_size > 0u) {
3600         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3601         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3602         if (connection) {
3603             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3604                 hci_send_acl_packet_fragments(connection);
3605                 return true;
3606             }
3607         } else {
3608             // connection gone -> discard further fragments
3609             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3610             hci_stack->acl_fragmentation_total_size = 0;
3611             hci_stack->acl_fragmentation_pos = 0;
3612         }
3613     }
3614     return false;
3615 }
3616 
3617 #ifdef ENABLE_CLASSIC
3618 static bool hci_run_general_gap_classic(void){
3619 
3620     // decline incoming connections
3621     if (hci_stack->decline_reason){
3622         uint8_t reason = hci_stack->decline_reason;
3623         hci_stack->decline_reason = 0;
3624         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3625         return true;
3626     }
3627     // send scan enable
3628     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3629         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3630         hci_stack->new_scan_enable_value = 0xff;
3631         return true;
3632     }
3633     // start/stop inquiry
3634     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3635         uint8_t duration = hci_stack->inquiry_state;
3636         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3637         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3638         return true;
3639     }
3640     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3641         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3642         hci_send_cmd(&hci_inquiry_cancel);
3643         return true;
3644     }
3645     // remote name request
3646     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3647         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3648         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3649                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3650         return true;
3651     }
3652     // pairing
3653     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3654         uint8_t state = hci_stack->gap_pairing_state;
3655         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3656         switch (state){
3657             case GAP_PAIRING_STATE_SEND_PIN:
3658                 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);
3659                 break;
3660             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3661                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3662                 break;
3663             case GAP_PAIRING_STATE_SEND_PASSKEY:
3664                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3665                 break;
3666             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3667                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3668                 break;
3669             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3670                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3671                 break;
3672             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3673                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3674                 break;
3675             default:
3676                 break;
3677         }
3678         return true;
3679     }
3680     return false;
3681 }
3682 #endif
3683 
3684 #ifdef ENABLE_BLE
3685 static bool hci_run_general_gap_le(void){
3686 
3687     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3688 
3689     if (hci_stack->state != HCI_STATE_WORKING) return false;
3690     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3691 
3692 
3693     // Phase 1: collect what to stop
3694 
3695     bool scanning_stop = false;
3696     bool connecting_stop = false;
3697     bool advertising_stop = false;
3698 
3699 #ifndef ENABLE_LE_CENTRAL
3700     UNUSED(scanning_stop);
3701     UNUSED(connecting_stop);
3702 #endif
3703 #ifndef ENABLE_LE_PERIPHERAL
3704     UNUSED(advertising_stop);
3705 #endif
3706 
3707     // check if whitelist needs modification
3708     bool whitelist_modification_pending = false;
3709     btstack_linked_list_iterator_t lit;
3710     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3711     while (btstack_linked_list_iterator_has_next(&lit)){
3712         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3713         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3714             whitelist_modification_pending = true;
3715             break;
3716         }
3717     }
3718     // check if resolving list needs modification
3719     bool resolving_list_modification_pending = false;
3720 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3721     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
3722 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
3723         resolving_list_modification_pending = true;
3724     }
3725 #endif
3726 
3727 #ifdef ENABLE_LE_CENTRAL
3728     // scanning control
3729     if (hci_stack->le_scanning_active) {
3730         // stop if:
3731         // - parameter change required
3732         // - it's disabled
3733         // - whitelist change required but used for scanning
3734         // - resolving list modified
3735         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3736         if ((hci_stack->le_scanning_param_update) ||
3737             !hci_stack->le_scanning_enabled ||
3738             scanning_uses_whitelist ||
3739             resolving_list_modification_pending){
3740 
3741             scanning_stop = true;
3742         }
3743     }
3744 #endif
3745 
3746 #ifdef ENABLE_LE_CENTRAL
3747     // connecting control
3748     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3749         // stop connecting if:
3750         // - connecting uses white and whitelist modification pending
3751         // - if it got disabled
3752         // - resolving list modified
3753         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3754         if ((connecting_uses_whitelist && whitelist_modification_pending) ||
3755             (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
3756             resolving_list_modification_pending) {
3757 
3758             connecting_stop = true;
3759         }
3760     }
3761 #endif
3762 
3763 #ifdef ENABLE_LE_PERIPHERAL
3764     // le advertisement control
3765     if (hci_stack->le_advertisements_active){
3766         // stop if:
3767         // - parameter change required
3768         // - it's disabled
3769         // - whitelist change required but used for advertisement filter policy
3770         // - resolving list modified
3771         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3772         if ((hci_stack->le_advertisements_todo != 0) ||
3773             !hci_stack->le_advertisements_enabled_for_current_roles ||
3774             (advertising_uses_whitelist & whitelist_modification_pending) ||
3775             resolving_list_modification_pending) {
3776 
3777             advertising_stop = true;
3778         }
3779     }
3780 #endif
3781 
3782 
3783     // Phase 2: stop everything that should be off during modifications
3784 
3785 #ifdef ENABLE_LE_CENTRAL
3786     if (scanning_stop){
3787         hci_stack->le_scanning_active = false;
3788         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3789         return true;
3790     }
3791 #endif
3792 
3793 #ifdef ENABLE_LE_CENTRAL
3794     if (connecting_stop){
3795         if (hci_stack->le_connecting_state != LE_CONNECTING_CANCEL){
3796             hci_send_cmd(&hci_le_create_connection_cancel);
3797             return true;
3798         }
3799     }
3800 #endif
3801 
3802 #ifdef ENABLE_LE_PERIPHERAL
3803     if (advertising_stop){
3804         hci_stack->le_advertisements_active = false;
3805         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3806         return true;
3807     }
3808 #endif
3809 
3810     // Phase 3: modify
3811 
3812 #ifdef ENABLE_LE_CENTRAL
3813     if (hci_stack->le_scanning_param_update){
3814         hci_stack->le_scanning_param_update = false;
3815         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3816                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3817         return true;
3818     }
3819 #endif
3820 
3821 #ifdef ENABLE_LE_PERIPHERAL
3822     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3823         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3824         hci_send_cmd(&hci_le_set_advertising_parameters,
3825                      hci_stack->le_advertisements_interval_min,
3826                      hci_stack->le_advertisements_interval_max,
3827                      hci_stack->le_advertisements_type,
3828                      hci_stack->le_own_addr_type,
3829                      hci_stack->le_advertisements_direct_address_type,
3830                      hci_stack->le_advertisements_direct_address,
3831                      hci_stack->le_advertisements_channel_map,
3832                      hci_stack->le_advertisements_filter_policy);
3833         return true;
3834     }
3835     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3836         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3837         uint8_t adv_data_clean[31];
3838         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3839         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3840                      hci_stack->le_advertisements_data_len);
3841         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3842         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3843         return true;
3844     }
3845     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3846         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3847         uint8_t scan_data_clean[31];
3848         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3849         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3850                      hci_stack->le_scan_response_data_len);
3851         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3852         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3853         return true;
3854     }
3855 #endif
3856 
3857 
3858 #ifdef ENABLE_LE_CENTRAL
3859     // if connect with whitelist was active and is not cancelled yet, wait until next time
3860     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
3861 #endif
3862 
3863     // LE Whitelist Management
3864     if (whitelist_modification_pending){
3865         // add/remove entries
3866         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3867         while (btstack_linked_list_iterator_has_next(&lit)){
3868             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3869 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3870 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3871 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
3872 				return true;
3873 			}
3874             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3875 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
3876                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
3877                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3878                 return true;
3879             }
3880             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
3881 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3882 				btstack_memory_whitelist_entry_free(entry);
3883             }
3884         }
3885     }
3886 
3887 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3888     // LE Resolving List Management
3889     if (resolving_list_supported) {
3890 		uint16_t i;
3891 		switch (hci_stack->le_resolving_list_state) {
3892 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
3893 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
3894 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
3895 				return true;
3896 			case LE_RESOLVING_LIST_READ_SIZE:
3897 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
3898 				hci_send_cmd(&hci_le_read_resolving_list_size);
3899 				return true;
3900 			case LE_RESOLVING_LIST_SEND_CLEAR:
3901 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
3902 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
3903 							  sizeof(hci_stack->le_resolving_list_add_entries));
3904 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
3905 							  sizeof(hci_stack->le_resolving_list_remove_entries));
3906 				hci_send_cmd(&hci_le_clear_resolving_list);
3907 				return true;
3908 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
3909 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3910 					uint8_t offset = i >> 3;
3911 					uint8_t mask = 1 << (i & 7);
3912 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
3913 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
3914 					bd_addr_t peer_identity_addreses;
3915 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3916 					sm_key_t peer_irk;
3917 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3918 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3919 
3920 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
3921 					// trigger whitelist entry 'update' (work around for controller bug)
3922 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3923 					while (btstack_linked_list_iterator_has_next(&lit)) {
3924 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
3925 						if (entry->address_type != peer_identity_addr_type) continue;
3926 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
3927 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
3928 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
3929 					}
3930 #endif
3931 
3932 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
3933 								 peer_identity_addreses);
3934 					return true;
3935 				}
3936 
3937 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
3938 
3939 				/* fall through */
3940 
3941 			case LE_RESOLVING_LIST_ADD_ENTRIES:
3942 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
3943 					uint8_t offset = i >> 3;
3944 					uint8_t mask = 1 << (i & 7);
3945 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
3946 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
3947 					bd_addr_t peer_identity_addreses;
3948 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3949 					sm_key_t peer_irk;
3950 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3951 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3952 					const uint8_t *local_irk = gap_get_persistent_irk();
3953 					// command uses format specifier 'P' that stores 16-byte value without flip
3954 					uint8_t local_irk_flipped[16];
3955 					uint8_t peer_irk_flipped[16];
3956 					reverse_128(local_irk, local_irk_flipped);
3957 					reverse_128(peer_irk, peer_irk_flipped);
3958 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
3959 								 peer_irk_flipped, local_irk_flipped);
3960 					return true;
3961 				}
3962 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3963 				break;
3964 
3965 			default:
3966 				break;
3967 		}
3968 	}
3969     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3970 #endif
3971 
3972     // Phase 4: restore state
3973 
3974 #ifdef ENABLE_LE_CENTRAL
3975     // re-start scanning
3976     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3977         hci_stack->le_scanning_active = true;
3978         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3979         return true;
3980     }
3981 #endif
3982 
3983 #ifdef ENABLE_LE_CENTRAL
3984     // re-start connecting
3985     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3986         bd_addr_t null_addr;
3987         memset(null_addr, 0, 6);
3988         hci_send_cmd(&hci_le_create_connection,
3989                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3990                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3991                      1,         // use whitelist
3992                      0,         // peer address type
3993                      null_addr, // peer bd addr
3994                      hci_stack->le_own_addr_type, // our addr type:
3995                      hci_stack->le_connection_interval_min,    // conn interval min
3996                      hci_stack->le_connection_interval_max,    // conn interval max
3997                      hci_stack->le_connection_latency,         // conn latency
3998                      hci_stack->le_supervision_timeout,        // conn latency
3999                      hci_stack->le_minimum_ce_length,          // min ce length
4000                      hci_stack->le_maximum_ce_length           // max ce length
4001         );
4002         return true;
4003     }
4004 #endif
4005 
4006 #ifdef ENABLE_LE_PERIPHERAL
4007     // re-start advertising
4008     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4009         // check if advertisements should be enabled given
4010         hci_stack->le_advertisements_active = true;
4011         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4012         return true;
4013     }
4014 #endif
4015 
4016     return false;
4017 }
4018 #endif
4019 
4020 static bool hci_run_general_pending_commands(void){
4021     btstack_linked_item_t * it;
4022     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4023         hci_connection_t * connection = (hci_connection_t *) it;
4024 
4025         switch(connection->state){
4026             case SEND_CREATE_CONNECTION:
4027                 switch(connection->address_type){
4028 #ifdef ENABLE_CLASSIC
4029                     case BD_ADDR_TYPE_ACL:
4030                         log_info("sending hci_create_connection");
4031                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4032                         break;
4033 #endif
4034                     default:
4035 #ifdef ENABLE_BLE
4036 #ifdef ENABLE_LE_CENTRAL
4037                         log_info("sending hci_le_create_connection");
4038                         hci_send_cmd(&hci_le_create_connection,
4039                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4040                                      hci_stack->le_connection_scan_window,      // conn scan windows
4041                                      0,         // don't use whitelist
4042                                      connection->address_type, // peer address type
4043                                      connection->address,      // peer bd addr
4044                                      hci_stack->le_own_addr_type, // our addr type:
4045                                      hci_stack->le_connection_interval_min,    // conn interval min
4046                                      hci_stack->le_connection_interval_max,    // conn interval max
4047                                      hci_stack->le_connection_latency,         // conn latency
4048                                      hci_stack->le_supervision_timeout,        // conn latency
4049                                      hci_stack->le_minimum_ce_length,          // min ce length
4050                                      hci_stack->le_maximum_ce_length          // max ce length
4051                         );
4052                         connection->state = SENT_CREATE_CONNECTION;
4053 #endif
4054 #endif
4055                         break;
4056                 }
4057                 return true;
4058 
4059 #ifdef ENABLE_CLASSIC
4060             case RECEIVED_CONNECTION_REQUEST:
4061                 connection->role  = HCI_ROLE_SLAVE;
4062                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4063                     log_info("sending hci_accept_connection_request");
4064                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4065                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4066                 }
4067                 return true;
4068 #endif
4069 
4070 #ifdef ENABLE_BLE
4071 #ifdef ENABLE_LE_CENTRAL
4072             case SEND_CANCEL_CONNECTION:
4073                 connection->state = SENT_CANCEL_CONNECTION;
4074                 hci_send_cmd(&hci_le_create_connection_cancel);
4075                 return true;
4076 #endif
4077 #endif
4078             case SEND_DISCONNECT:
4079                 connection->state = SENT_DISCONNECT;
4080                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4081                 return true;
4082 
4083             default:
4084                 break;
4085         }
4086 
4087         // no further commands if connection is about to get shut down
4088         if (connection->state == SENT_DISCONNECT) continue;
4089 
4090         if (connection->authentication_flags & READ_RSSI){
4091             connectionClearAuthenticationFlags(connection, READ_RSSI);
4092             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4093             return true;
4094         }
4095 
4096 #ifdef ENABLE_CLASSIC
4097 
4098         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4099             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4100             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4101             return true;
4102         }
4103 
4104         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
4105             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4106             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4107 
4108             link_key_t link_key;
4109             link_key_type_t link_key_type;
4110             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
4111 
4112             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4113             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4114             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
4115             if (sc_downgrade){
4116                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4117                 connection->state = SENT_DISCONNECT;
4118                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4119                 return true;
4120             }
4121 
4122             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
4123             if (have_link_key && security_level_sufficient){
4124                 connection->link_key_type = link_key_type;
4125                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
4126             } else {
4127                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4128             }
4129             return true;
4130         }
4131 
4132         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4133             log_info("denying to pin request");
4134             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4135             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4136             return true;
4137         }
4138 
4139         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4140             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4141             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
4142             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
4143                 // tweak authentication requirements
4144                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
4145                 if (connection->bonding_flags & BONDING_DEDICATED){
4146                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4147                 }
4148                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4149                     authreq |= 1;
4150                 }
4151                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
4152             } else {
4153                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4154             }
4155             return true;
4156         }
4157 
4158         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4159             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4160             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4161             return true;
4162         }
4163 
4164         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4165             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4166             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4167             return true;
4168         }
4169 
4170         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4171             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4172             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4173             return true;
4174         }
4175 
4176         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4177             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4178             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4179             return true;
4180         }
4181 
4182         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4183             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4184             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4185             return true;
4186         }
4187 
4188         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4189             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4190             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4191             connection->state = SENT_DISCONNECT;
4192             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4193             return true;
4194         }
4195 
4196         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4197             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4198             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4199             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4200             return true;
4201         }
4202 
4203         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4204             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4205             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4206             return true;
4207         }
4208         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4209             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4210             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4211             return true;
4212         }
4213 #endif
4214 
4215         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4216             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4217             if (connection->state != SENT_DISCONNECT){
4218                 connection->state = SENT_DISCONNECT;
4219                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4220                 return true;
4221             }
4222         }
4223 
4224 #ifdef ENABLE_CLASSIC
4225         uint16_t sniff_min_interval;
4226         switch (connection->sniff_min_interval){
4227             case 0:
4228                 break;
4229             case 0xffff:
4230                 connection->sniff_min_interval = 0;
4231                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4232                 return true;
4233             default:
4234                 sniff_min_interval = connection->sniff_min_interval;
4235                 connection->sniff_min_interval = 0;
4236                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4237                 return true;
4238         }
4239 
4240         if (connection->request_role != HCI_ROLE_INVALID){
4241             hci_role_t  role = connection->request_role;
4242             connection->request_role = HCI_ROLE_INVALID;
4243             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4244             return true;
4245         }
4246 #endif
4247 
4248 #ifdef ENABLE_BLE
4249         switch (connection->le_con_parameter_update_state){
4250             // response to L2CAP CON PARAMETER UPDATE REQUEST
4251             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4252                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4253                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4254                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4255                              0x0000, 0xffff);
4256                 return true;
4257             case CON_PARAMETER_UPDATE_REPLY:
4258                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4259                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4260                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4261                              0x0000, 0xffff);
4262                 return true;
4263             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4264                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4265                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4266                 return true;
4267             default:
4268                 break;
4269         }
4270         if (connection->le_phy_update_all_phys != 0xffu){
4271             uint8_t all_phys = connection->le_phy_update_all_phys;
4272             connection->le_phy_update_all_phys = 0xff;
4273             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);
4274             return true;
4275         }
4276 #endif
4277     }
4278     return false;
4279 }
4280 
4281 static void hci_run(void){
4282 
4283     bool done;
4284 
4285     // send continuation fragments first, as they block the prepared packet buffer
4286     done = hci_run_acl_fragments();
4287     if (done) return;
4288 
4289 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4290     // send host num completed packets next as they don't require num_cmd_packets > 0
4291     if (!hci_can_send_comand_packet_transport()) return;
4292     if (hci_stack->host_completed_packets){
4293         hci_host_num_completed_packets();
4294         return;
4295     }
4296 #endif
4297 
4298     if (!hci_can_send_command_packet_now()) return;
4299 
4300     // global/non-connection oriented commands
4301 
4302 
4303 #ifdef ENABLE_CLASSIC
4304     // general gap classic
4305     done = hci_run_general_gap_classic();
4306     if (done) return;
4307 #endif
4308 
4309 #ifdef ENABLE_BLE
4310     // general gap le
4311     done = hci_run_general_gap_le();
4312     if (done) return;
4313 #endif
4314 
4315     // send pending HCI commands
4316     done = hci_run_general_pending_commands();
4317     if (done) return;
4318 
4319     // stack state sub statemachines
4320     hci_connection_t * connection;
4321     switch (hci_stack->state){
4322         case HCI_STATE_INITIALIZING:
4323             hci_initializing_run();
4324             break;
4325 
4326         case HCI_STATE_HALTING:
4327 
4328             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4329             switch (hci_stack->substate){
4330                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4331                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4332 
4333 #ifdef ENABLE_BLE
4334 #ifdef ENABLE_LE_CENTRAL
4335                     // free whitelist entries
4336                     {
4337                         btstack_linked_list_iterator_t lit;
4338                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4339                         while (btstack_linked_list_iterator_has_next(&lit)){
4340                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4341                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4342                             btstack_memory_whitelist_entry_free(entry);
4343                         }
4344                     }
4345 #endif
4346 #endif
4347                     // close all open connections
4348                     connection =  (hci_connection_t *) hci_stack->connections;
4349                     if (connection){
4350                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4351                         if (!hci_can_send_command_packet_now()) return;
4352 
4353                         // check state
4354                         if (connection->state == SENT_DISCONNECT) return;
4355                         connection->state = SENT_DISCONNECT;
4356 
4357                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4358 
4359                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4360                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4361 
4362                         // ... which would be ignored anyway as we shutdown (free) the connection now
4363                         hci_shutdown_connection(connection);
4364 
4365                         // finally, send the disconnect command
4366                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4367                         return;
4368                     }
4369 
4370                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4371                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4372                         log_info("HCI_STATE_HALTING: wait 50 ms");
4373                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4374                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4375                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4376                         btstack_run_loop_add_timer(&hci_stack->timeout);
4377                         break;
4378                     }
4379 
4380                     /* fall through */
4381 
4382                 case HCI_HALTING_CLOSE:
4383                     log_info("HCI_STATE_HALTING, calling off");
4384 
4385                     // switch mode
4386                     hci_power_control_off();
4387 
4388                     log_info("HCI_STATE_HALTING, emitting state");
4389                     hci_emit_state();
4390                     log_info("HCI_STATE_HALTING, done");
4391                     break;
4392 
4393                 case HCI_HALTING_W4_TIMER:
4394                     // keep waiting
4395 
4396                     break;
4397                 default:
4398                     break;
4399             }
4400 
4401             break;
4402 
4403         case HCI_STATE_FALLING_ASLEEP:
4404             switch(hci_stack->substate) {
4405                 case HCI_FALLING_ASLEEP_DISCONNECT:
4406                     log_info("HCI_STATE_FALLING_ASLEEP");
4407                     // close all open connections
4408                     connection =  (hci_connection_t *) hci_stack->connections;
4409 
4410 #ifdef HAVE_PLATFORM_IPHONE_OS
4411                     // don't close connections, if H4 supports power management
4412                     if (btstack_control_iphone_power_management_enabled()){
4413                         connection = NULL;
4414                     }
4415 #endif
4416                     if (connection){
4417 
4418                         // send disconnect
4419                         if (!hci_can_send_command_packet_now()) return;
4420 
4421                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4422                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4423 
4424                         // send disconnected event right away - causes higher layer connections to get closed, too.
4425                         hci_shutdown_connection(connection);
4426                         return;
4427                     }
4428 
4429                     if (hci_classic_supported()){
4430                         // disable page and inquiry scan
4431                         if (!hci_can_send_command_packet_now()) return;
4432 
4433                         log_info("HCI_STATE_HALTING, disabling inq scans");
4434                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4435 
4436                         // continue in next sub state
4437                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4438                         break;
4439                     }
4440 
4441                     /* fall through */
4442 
4443                 case HCI_FALLING_ASLEEP_COMPLETE:
4444                     log_info("HCI_STATE_HALTING, calling sleep");
4445 #ifdef HAVE_PLATFORM_IPHONE_OS
4446                     // don't actually go to sleep, if H4 supports power management
4447                     if (btstack_control_iphone_power_management_enabled()){
4448                         // SLEEP MODE reached
4449                         hci_stack->state = HCI_STATE_SLEEPING;
4450                         hci_emit_state();
4451                         break;
4452                     }
4453 #endif
4454                     // switch mode
4455                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4456                     hci_emit_state();
4457                     break;
4458 
4459                 default:
4460                     break;
4461             }
4462             break;
4463 
4464         default:
4465             break;
4466     }
4467 }
4468 
4469 int hci_send_cmd_packet(uint8_t *packet, int size){
4470     // house-keeping
4471 
4472 #ifdef ENABLE_CLASSIC
4473     bd_addr_t addr;
4474     hci_connection_t * conn;
4475 #endif
4476 #ifdef ENABLE_LE_CENTRAL
4477     uint8_t initiator_filter_policy;
4478 #endif
4479 
4480     uint16_t opcode = little_endian_read_16(packet, 0);
4481     switch (opcode) {
4482         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4483             hci_stack->loopback_mode = packet[3];
4484             break;
4485 
4486 #ifdef ENABLE_CLASSIC
4487         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4488             reverse_bd_addr(&packet[3], addr);
4489             log_info("Create_connection to %s", bd_addr_to_str(addr));
4490 
4491             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4492             if (!conn) {
4493                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4494                 if (!conn) {
4495                     // notify client that alloc failed
4496                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4497                     return -1; // packet not sent to controller
4498                 }
4499                 conn->state = SEND_CREATE_CONNECTION;
4500                 conn->role  = HCI_ROLE_MASTER;
4501             }
4502             log_info("conn state %u", conn->state);
4503             switch (conn->state) {
4504                 // if connection active exists
4505                 case OPEN:
4506                     // and OPEN, emit connection complete command
4507                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4508                     return -1; // packet not sent to controller
4509                 case RECEIVED_DISCONNECTION_COMPLETE:
4510                     // create connection triggered in disconnect complete event, let's do it now
4511                     break;
4512                 case SEND_CREATE_CONNECTION:
4513                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4514                     break;
4515                 default:
4516                     // otherwise, just ignore as it is already in the open process
4517                     return -1; // packet not sent to controller
4518             }
4519             conn->state = SENT_CREATE_CONNECTION;
4520 
4521             // track outgoing connection
4522             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4523             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4524             break;
4525         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4526             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4527             break;
4528         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4529             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4530             break;
4531         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4532             if (hci_stack->link_key_db) {
4533                 reverse_bd_addr(&packet[3], addr);
4534                 hci_stack->link_key_db->delete_link_key(addr);
4535             }
4536             break;
4537         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4538         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4539             reverse_bd_addr(&packet[3], addr);
4540             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4541             if (conn) {
4542                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4543             }
4544             break;
4545         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4546         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4547         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4548         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4549             reverse_bd_addr(&packet[3], addr);
4550             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4551             if (conn) {
4552                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4553             }
4554             break;
4555 
4556 #ifdef ENABLE_SCO_OVER_HCI
4557         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4558             // setup_synchronous_connection? Voice setting at offset 22
4559             // TODO: compare to current setting if sco connection already active
4560             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4561             break;
4562         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4563             // accept_synchronus_connection? Voice setting at offset 18
4564             // TODO: compare to current setting if sco connection already active
4565             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4566             break;
4567 #endif
4568 #endif
4569 
4570 #ifdef ENABLE_BLE
4571         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4572             hci_stack->le_random_address_set = 1;
4573             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4574             break;
4575 #ifdef ENABLE_LE_PERIPHERAL
4576         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4577             hci_stack->le_advertisements_active = packet[3] != 0;
4578             break;
4579 #endif
4580 #ifdef ENABLE_LE_CENTRAL
4581         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4582             // white list used?
4583             initiator_filter_policy = packet[7];
4584             switch (initiator_filter_policy) {
4585                 case 0:
4586                     // whitelist not used
4587                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4588                     break;
4589                 case 1:
4590                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4591                     break;
4592                 default:
4593                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4594                     break;
4595             }
4596             // track outgoing connection
4597             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4598             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4599             break;
4600         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4601             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4602             break;
4603 #endif
4604 #endif
4605         default:
4606             break;
4607     }
4608 
4609     hci_stack->num_cmd_packets--;
4610 
4611     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4612     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4613 }
4614 
4615 // disconnect because of security block
4616 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4617     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4618     if (!connection) return;
4619     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4620 }
4621 
4622 
4623 // Configure Secure Simple Pairing
4624 
4625 #ifdef ENABLE_CLASSIC
4626 
4627 // enable will enable SSP during init
4628 void gap_ssp_set_enable(int enable){
4629     hci_stack->ssp_enable = enable;
4630 }
4631 
4632 static int hci_local_ssp_activated(void){
4633     return gap_ssp_supported() && hci_stack->ssp_enable;
4634 }
4635 
4636 // if set, BTstack will respond to io capability request using authentication requirement
4637 void gap_ssp_set_io_capability(int io_capability){
4638     hci_stack->ssp_io_capability = io_capability;
4639 }
4640 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4641     hci_stack->ssp_authentication_requirement = authentication_requirement;
4642 }
4643 
4644 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4645 void gap_ssp_set_auto_accept(int auto_accept){
4646     hci_stack->ssp_auto_accept = auto_accept;
4647 }
4648 
4649 void gap_secure_connections_enable(bool enable){
4650     hci_stack->secure_connections_enable = enable;
4651 }
4652 
4653 #endif
4654 
4655 // va_list part of hci_send_cmd
4656 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4657     if (!hci_can_send_command_packet_now()){
4658         log_error("hci_send_cmd called but cannot send packet now");
4659         return 0;
4660     }
4661 
4662     // for HCI INITIALIZATION
4663     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4664     hci_stack->last_cmd_opcode = cmd->opcode;
4665 
4666     hci_reserve_packet_buffer();
4667     uint8_t * packet = hci_stack->hci_packet_buffer;
4668     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4669     int err = hci_send_cmd_packet(packet, size);
4670 
4671     // release packet buffer on error or for synchronous transport implementations
4672     if ((err < 0) || hci_transport_synchronous()){
4673         hci_release_packet_buffer();
4674         hci_emit_transport_packet_sent();
4675     }
4676 
4677     return err;
4678 }
4679 
4680 /**
4681  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4682  */
4683 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4684     va_list argptr;
4685     va_start(argptr, cmd);
4686     int res = hci_send_cmd_va_arg(cmd, argptr);
4687     va_end(argptr);
4688     return res;
4689 }
4690 
4691 // Create various non-HCI events.
4692 // TODO: generalize, use table similar to hci_create_command
4693 
4694 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4695     // dump packet
4696     if (dump) {
4697         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4698     }
4699 
4700     // dispatch to all event handlers
4701     btstack_linked_list_iterator_t it;
4702     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4703     while (btstack_linked_list_iterator_has_next(&it)){
4704         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4705         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4706     }
4707 }
4708 
4709 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4710     if (!hci_stack->acl_packet_handler) return;
4711     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4712 }
4713 
4714 #ifdef ENABLE_CLASSIC
4715 static void hci_notify_if_sco_can_send_now(void){
4716     // notify SCO sender if waiting
4717     if (!hci_stack->sco_waiting_for_can_send_now) return;
4718     if (hci_can_send_sco_packet_now()){
4719         hci_stack->sco_waiting_for_can_send_now = 0;
4720         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4721         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4722         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4723     }
4724 }
4725 
4726 // parsing end emitting has been merged to reduce code size
4727 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4728     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4729 
4730     uint8_t * eir_data;
4731     ad_context_t context;
4732     const uint8_t * name;
4733     uint8_t         name_len;
4734 
4735     if (size < 3) return;
4736 
4737     int event_type = hci_event_packet_get_type(packet);
4738     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4739     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4740 
4741     switch (event_type){
4742         case HCI_EVENT_INQUIRY_RESULT:
4743         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4744             if (size != (3 + (num_responses * 14))) return;
4745             break;
4746         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4747             if (size != 257) return;
4748             if (num_responses != 1) return;
4749             break;
4750         default:
4751             return;
4752     }
4753 
4754     // event[1] is set at the end
4755     int i;
4756     for (i=0; i<num_responses;i++){
4757         memset(event, 0, sizeof(event));
4758         event[0] = GAP_EVENT_INQUIRY_RESULT;
4759         uint8_t event_size = 18;    // if name is not set by EIR
4760 
4761         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4762         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4763         (void)memcpy(&event[9],
4764                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4765                      3); // class of device
4766         (void)memcpy(&event[12],
4767                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4768                      2); // clock offset
4769 
4770         switch (event_type){
4771             case HCI_EVENT_INQUIRY_RESULT:
4772                 // 14,15,16,17 = 0, size 18
4773                 break;
4774             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4775                 event[14] = 1;
4776                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4777                 // 16,17 = 0, size 18
4778                 break;
4779             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4780                 event[14] = 1;
4781                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4782                 // EIR packets only contain a single inquiry response
4783                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4784                 name = NULL;
4785                 // Iterate over EIR data
4786                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4787                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4788                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4789                     const uint8_t * data = ad_iterator_get_data(&context);
4790                     // Prefer Complete Local Name over Shortend Local Name
4791                     switch (data_type){
4792                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4793                             if (name) continue;
4794                             /* fall through */
4795                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4796                             name = data;
4797                             name_len = data_size;
4798                             break;
4799                         default:
4800                             break;
4801                     }
4802                 }
4803                 if (name){
4804                     event[16] = 1;
4805                     // truncate name if needed
4806                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4807                     event[17] = len;
4808                     (void)memcpy(&event[18], name, len);
4809                     event_size += len;
4810                 }
4811                 break;
4812             default:
4813                 return;
4814         }
4815         event[1] = event_size - 2;
4816         hci_emit_event(event, event_size, 1);
4817     }
4818 }
4819 #endif
4820 
4821 void hci_emit_state(void){
4822     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4823     uint8_t event[3];
4824     event[0] = BTSTACK_EVENT_STATE;
4825     event[1] = sizeof(event) - 2u;
4826     event[2] = hci_stack->state;
4827     hci_emit_event(event, sizeof(event), 1);
4828 }
4829 
4830 #ifdef ENABLE_CLASSIC
4831 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4832     uint8_t event[13];
4833     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4834     event[1] = sizeof(event) - 2;
4835     event[2] = status;
4836     little_endian_store_16(event, 3, con_handle);
4837     reverse_bd_addr(address, &event[5]);
4838     event[11] = 1; // ACL connection
4839     event[12] = 0; // encryption disabled
4840     hci_emit_event(event, sizeof(event), 1);
4841 }
4842 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4843     if (disable_l2cap_timeouts) return;
4844     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4845     uint8_t event[4];
4846     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4847     event[1] = sizeof(event) - 2;
4848     little_endian_store_16(event, 2, conn->con_handle);
4849     hci_emit_event(event, sizeof(event), 1);
4850 }
4851 #endif
4852 
4853 #ifdef ENABLE_BLE
4854 #ifdef ENABLE_LE_CENTRAL
4855 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){
4856     uint8_t event[21];
4857     event[0] = HCI_EVENT_LE_META;
4858     event[1] = sizeof(event) - 2u;
4859     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4860     event[3] = status;
4861     little_endian_store_16(event, 4, con_handle);
4862     event[6] = 0; // TODO: role
4863     event[7] = address_type;
4864     reverse_bd_addr(address, &event[8]);
4865     little_endian_store_16(event, 14, 0); // interval
4866     little_endian_store_16(event, 16, 0); // latency
4867     little_endian_store_16(event, 18, 0); // supervision timeout
4868     event[20] = 0; // master clock accuracy
4869     hci_emit_event(event, sizeof(event), 1);
4870 }
4871 #endif
4872 #endif
4873 
4874 static void hci_emit_transport_packet_sent(void){
4875     // notify upper stack that it might be possible to send again
4876     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4877     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4878 }
4879 
4880 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4881     uint8_t event[6];
4882     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4883     event[1] = sizeof(event) - 2u;
4884     event[2] = 0; // status = OK
4885     little_endian_store_16(event, 3, con_handle);
4886     event[5] = reason;
4887     hci_emit_event(event, sizeof(event), 1);
4888 }
4889 
4890 static void hci_emit_nr_connections_changed(void){
4891     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4892     uint8_t event[3];
4893     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4894     event[1] = sizeof(event) - 2u;
4895     event[2] = nr_hci_connections();
4896     hci_emit_event(event, sizeof(event), 1);
4897 }
4898 
4899 static void hci_emit_hci_open_failed(void){
4900     log_info("BTSTACK_EVENT_POWERON_FAILED");
4901     uint8_t event[2];
4902     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4903     event[1] = sizeof(event) - 2u;
4904     hci_emit_event(event, sizeof(event), 1);
4905 }
4906 
4907 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4908     log_info("hci_emit_dedicated_bonding_result %u ", status);
4909     uint8_t event[9];
4910     int pos = 0;
4911     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4912     event[pos++] = sizeof(event) - 2u;
4913     event[pos++] = status;
4914     reverse_bd_addr(address, &event[pos]);
4915     hci_emit_event(event, sizeof(event), 1);
4916 }
4917 
4918 
4919 #ifdef ENABLE_CLASSIC
4920 
4921 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4922     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4923     uint8_t event[5];
4924     int pos = 0;
4925     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4926     event[pos++] = sizeof(event) - 2;
4927     little_endian_store_16(event, 2, con_handle);
4928     pos += 2;
4929     event[pos++] = level;
4930     hci_emit_event(event, sizeof(event), 1);
4931 }
4932 
4933 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4934     if (!connection) return LEVEL_0;
4935     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4936     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4937     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4938     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4939     // LEVEL 4 always requires 128 bit encrytion key size
4940     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4941         security_level = LEVEL_3;
4942     }
4943     return security_level;
4944 }
4945 
4946 static void hci_emit_discoverable_enabled(uint8_t enabled){
4947     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4948     uint8_t event[3];
4949     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4950     event[1] = sizeof(event) - 2;
4951     event[2] = enabled;
4952     hci_emit_event(event, sizeof(event), 1);
4953 }
4954 
4955 // query if remote side supports eSCO
4956 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4957     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4958     if (!connection) return 0;
4959     return (connection->remote_supported_features[0] & 1) != 0;
4960 }
4961 
4962 static bool hci_ssp_supported(hci_connection_t * connection){
4963     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4964     return (connection->bonding_flags & mask) == mask;
4965 }
4966 
4967 // query if remote side supports SSP
4968 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4969     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4970     if (!connection) return 0;
4971     return hci_ssp_supported(connection) ? 1 : 0;
4972 }
4973 
4974 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4975     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4976 }
4977 
4978 // GAP API
4979 /**
4980  * @bbrief enable/disable bonding. default is enabled
4981  * @praram enabled
4982  */
4983 void gap_set_bondable_mode(int enable){
4984     hci_stack->bondable = enable ? 1 : 0;
4985 }
4986 /**
4987  * @brief Get bondable mode.
4988  * @return 1 if bondable
4989  */
4990 int gap_get_bondable_mode(void){
4991     return hci_stack->bondable;
4992 }
4993 
4994 /**
4995  * @brief map link keys to security levels
4996  */
4997 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4998     switch (link_key_type){
4999         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5000             return LEVEL_4;
5001         case COMBINATION_KEY:
5002         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5003             return LEVEL_3;
5004         default:
5005             return LEVEL_2;
5006     }
5007 }
5008 
5009 /**
5010  * @brief map link keys to secure connection yes/no
5011  */
5012 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5013     switch (link_key_type){
5014         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5015         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5016             return 1;
5017         default:
5018             return 0;
5019     }
5020 }
5021 
5022 /**
5023  * @brief map link keys to authenticated
5024  */
5025 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5026     switch (link_key_type){
5027         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5028         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5029             return 1;
5030         default:
5031             return 0;
5032     }
5033 }
5034 
5035 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5036     log_info("gap_mitm_protection_required_for_security_level %u", level);
5037     return level > LEVEL_2;
5038 }
5039 
5040 /**
5041  * @brief get current security level
5042  */
5043 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5044     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5045     if (!connection) return LEVEL_0;
5046     return gap_security_level_for_connection(connection);
5047 }
5048 
5049 /**
5050  * @brief request connection to device to
5051  * @result GAP_AUTHENTICATION_RESULT
5052  */
5053 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5054     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5055     if (!connection){
5056         hci_emit_security_level(con_handle, LEVEL_0);
5057         return;
5058     }
5059 
5060     btstack_assert(hci_is_le_connection(connection) == false);
5061 
5062     gap_security_level_t current_level = gap_security_level(con_handle);
5063     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5064         requested_level, connection->requested_security_level, current_level);
5065 
5066     // assumption: earlier requested security higher than current level => security request is active
5067     if (current_level < connection->requested_security_level){
5068         if (connection->requested_security_level < requested_level){
5069             // increase requested level as new level is higher
5070 
5071             // TODO: handle re-authentication when done
5072 
5073             connection->requested_security_level = requested_level;
5074         }
5075         return;
5076     }
5077 
5078     // no request active, notify if security sufficient
5079     if (requested_level <= current_level){
5080         hci_emit_security_level(con_handle, current_level);
5081         return;
5082     }
5083 
5084     // store request
5085     connection->requested_security_level = requested_level;
5086 
5087     // start to authenticate connection if authentication not already active
5088     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
5089     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5090     hci_run();
5091 }
5092 
5093 /**
5094  * @brief start dedicated bonding with device. disconnect after bonding
5095  * @param device
5096  * @param request MITM protection
5097  * @result GAP_DEDICATED_BONDING_COMPLETE
5098  */
5099 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5100 
5101     // create connection state machine
5102     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5103 
5104     if (!connection){
5105         return BTSTACK_MEMORY_ALLOC_FAILED;
5106     }
5107 
5108     // delete linkn key
5109     gap_drop_link_key_for_bd_addr(device);
5110 
5111     // configure LEVEL_2/3, dedicated bonding
5112     connection->state = SEND_CREATE_CONNECTION;
5113     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5114     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5115     connection->bonding_flags = BONDING_DEDICATED;
5116 
5117     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5118 
5119     // handle: connnection failure (connection complete != ok)
5120     // handle: authentication failure
5121     // handle: disconnect on done
5122 
5123     hci_run();
5124 
5125     return 0;
5126 }
5127 #endif
5128 
5129 void gap_set_local_name(const char * local_name){
5130     hci_stack->local_name = local_name;
5131 }
5132 
5133 
5134 #ifdef ENABLE_BLE
5135 
5136 #ifdef ENABLE_LE_CENTRAL
5137 void gap_start_scan(void){
5138     hci_stack->le_scanning_enabled = true;
5139     hci_run();
5140 }
5141 
5142 void gap_stop_scan(void){
5143     hci_stack->le_scanning_enabled = false;
5144     hci_run();
5145 }
5146 
5147 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5148     hci_stack->le_scan_type          = scan_type;
5149     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5150     hci_stack->le_scan_interval      = scan_interval;
5151     hci_stack->le_scan_window        = scan_window;
5152     hci_stack->le_scanning_param_update = true;
5153     hci_run();
5154 }
5155 
5156 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5157     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5158 }
5159 
5160 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5161     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5162     if (!conn){
5163         // disallow if le connection is already outgoing
5164         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5165             log_error("le connection already active");
5166             return ERROR_CODE_COMMAND_DISALLOWED;
5167         }
5168 
5169         log_info("gap_connect: no connection exists yet, creating context");
5170         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5171         if (!conn){
5172             // notify client that alloc failed
5173             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5174             log_info("gap_connect: failed to alloc hci_connection_t");
5175             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5176         }
5177 
5178         // set le connecting state
5179         if (hci_is_le_connection_type(addr_type)){
5180             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5181         }
5182 
5183         conn->state = SEND_CREATE_CONNECTION;
5184         log_info("gap_connect: send create connection next");
5185         hci_run();
5186         return ERROR_CODE_SUCCESS;
5187     }
5188 
5189     if (!hci_is_le_connection(conn) ||
5190         (conn->state == SEND_CREATE_CONNECTION) ||
5191         (conn->state == SENT_CREATE_CONNECTION)) {
5192         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5193         log_error("gap_connect: classic connection or connect is already being created");
5194         return GATT_CLIENT_IN_WRONG_STATE;
5195     }
5196 
5197     // check if connection was just disconnected
5198     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5199         log_info("gap_connect: send create connection (again)");
5200         conn->state = SEND_CREATE_CONNECTION;
5201         hci_run();
5202         return ERROR_CODE_SUCCESS;
5203     }
5204 
5205     log_info("gap_connect: context exists with state %u", conn->state);
5206     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5207     hci_run();
5208     return ERROR_CODE_SUCCESS;
5209 }
5210 
5211 // @assumption: only a single outgoing LE Connection exists
5212 static hci_connection_t * gap_get_outgoing_connection(void){
5213     btstack_linked_item_t *it;
5214     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5215         hci_connection_t * conn = (hci_connection_t *) it;
5216         if (!hci_is_le_connection(conn)) continue;
5217         switch (conn->state){
5218             case SEND_CREATE_CONNECTION:
5219             case SENT_CREATE_CONNECTION:
5220             case SENT_CANCEL_CONNECTION:
5221                 return conn;
5222             default:
5223                 break;
5224         };
5225     }
5226     return NULL;
5227 }
5228 
5229 uint8_t gap_connect_cancel(void){
5230     hci_connection_t * conn = gap_get_outgoing_connection();
5231     if (!conn) return 0;
5232     switch (conn->state){
5233         case SEND_CREATE_CONNECTION:
5234             // skip sending create connection and emit event instead
5235             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5236             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5237             btstack_memory_hci_connection_free( conn );
5238             break;
5239         case SENT_CREATE_CONNECTION:
5240             // request to send cancel connection
5241             conn->state = SEND_CANCEL_CONNECTION;
5242             hci_run();
5243             break;
5244         default:
5245             break;
5246     }
5247     return 0;
5248 }
5249 #endif
5250 
5251 #ifdef ENABLE_LE_CENTRAL
5252 /**
5253  * @brief Set connection parameters for outgoing connections
5254  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5255  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5256  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5257  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5258  * @param conn_latency, default: 4
5259  * @param supervision_timeout (unit: 10ms), default: 720 ms
5260  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5261  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5262  */
5263 
5264 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5265     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5266     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5267     hci_stack->le_connection_scan_interval = conn_scan_interval;
5268     hci_stack->le_connection_scan_window = conn_scan_window;
5269     hci_stack->le_connection_interval_min = conn_interval_min;
5270     hci_stack->le_connection_interval_max = conn_interval_max;
5271     hci_stack->le_connection_latency = conn_latency;
5272     hci_stack->le_supervision_timeout = supervision_timeout;
5273     hci_stack->le_minimum_ce_length = min_ce_length;
5274     hci_stack->le_maximum_ce_length = max_ce_length;
5275 }
5276 #endif
5277 
5278 /**
5279  * @brief Updates the connection parameters for a given LE connection
5280  * @param handle
5281  * @param conn_interval_min (unit: 1.25ms)
5282  * @param conn_interval_max (unit: 1.25ms)
5283  * @param conn_latency
5284  * @param supervision_timeout (unit: 10ms)
5285  * @returns 0 if ok
5286  */
5287 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5288     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5289     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5290     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5291     connection->le_conn_interval_min = conn_interval_min;
5292     connection->le_conn_interval_max = conn_interval_max;
5293     connection->le_conn_latency = conn_latency;
5294     connection->le_supervision_timeout = supervision_timeout;
5295     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5296     hci_run();
5297     return 0;
5298 }
5299 
5300 /**
5301  * @brief Request an update of the connection parameter for a given LE connection
5302  * @param handle
5303  * @param conn_interval_min (unit: 1.25ms)
5304  * @param conn_interval_max (unit: 1.25ms)
5305  * @param conn_latency
5306  * @param supervision_timeout (unit: 10ms)
5307  * @returns 0 if ok
5308  */
5309 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5310     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5311     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5312     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5313     connection->le_conn_interval_min = conn_interval_min;
5314     connection->le_conn_interval_max = conn_interval_max;
5315     connection->le_conn_latency = conn_latency;
5316     connection->le_supervision_timeout = supervision_timeout;
5317     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5318     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5319     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5320     return 0;
5321 }
5322 
5323 #ifdef ENABLE_LE_PERIPHERAL
5324 
5325 /**
5326  * @brief Set Advertisement Data
5327  * @param advertising_data_length
5328  * @param advertising_data (max 31 octets)
5329  * @note data is not copied, pointer has to stay valid
5330  */
5331 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5332     hci_stack->le_advertisements_data_len = advertising_data_length;
5333     hci_stack->le_advertisements_data = advertising_data;
5334     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5335     hci_run();
5336 }
5337 
5338 /**
5339  * @brief Set Scan Response Data
5340  * @param advertising_data_length
5341  * @param advertising_data (max 31 octets)
5342  * @note data is not copied, pointer has to stay valid
5343  */
5344 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5345     hci_stack->le_scan_response_data_len = scan_response_data_length;
5346     hci_stack->le_scan_response_data = scan_response_data;
5347     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5348     hci_run();
5349 }
5350 
5351 /**
5352  * @brief Set Advertisement Parameters
5353  * @param adv_int_min
5354  * @param adv_int_max
5355  * @param adv_type
5356  * @param direct_address_type
5357  * @param direct_address
5358  * @param channel_map
5359  * @param filter_policy
5360  *
5361  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5362  */
5363  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5364     uint8_t direct_address_typ, bd_addr_t direct_address,
5365     uint8_t channel_map, uint8_t filter_policy) {
5366 
5367     hci_stack->le_advertisements_interval_min = adv_int_min;
5368     hci_stack->le_advertisements_interval_max = adv_int_max;
5369     hci_stack->le_advertisements_type = adv_type;
5370     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5371     hci_stack->le_advertisements_channel_map = channel_map;
5372     hci_stack->le_advertisements_filter_policy = filter_policy;
5373     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5374                  6);
5375 
5376     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5377     hci_run();
5378  }
5379 
5380 /**
5381  * @brief Enable/Disable Advertisements
5382  * @param enabled
5383  */
5384 void gap_advertisements_enable(int enabled){
5385     hci_stack->le_advertisements_enabled = enabled != 0;
5386     hci_update_advertisements_enabled_for_current_roles();
5387     hci_run();
5388 }
5389 
5390 #endif
5391 
5392 void hci_le_set_own_address_type(uint8_t own_address_type){
5393     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5394     if (own_address_type == hci_stack->le_own_addr_type) return;
5395     hci_stack->le_own_addr_type = own_address_type;
5396 
5397 #ifdef ENABLE_LE_PERIPHERAL
5398     // update advertisement parameters, too
5399     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5400     hci_run();
5401 #endif
5402 #ifdef ENABLE_LE_CENTRAL
5403     // note: we don't update scan parameters or modify ongoing connection attempts
5404 #endif
5405 }
5406 
5407 #endif
5408 
5409 uint8_t gap_disconnect(hci_con_handle_t handle){
5410     hci_connection_t * conn = hci_connection_for_handle(handle);
5411     if (!conn){
5412         hci_emit_disconnection_complete(handle, 0);
5413         return 0;
5414     }
5415     // ignore if already disconnected
5416     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5417         return 0;
5418     }
5419     conn->state = SEND_DISCONNECT;
5420     hci_run();
5421     return 0;
5422 }
5423 
5424 int gap_read_rssi(hci_con_handle_t con_handle){
5425     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5426     if (hci_connection == NULL) return 0;
5427     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5428     hci_run();
5429     return 1;
5430 }
5431 
5432 /**
5433  * @brief Get connection type
5434  * @param con_handle
5435  * @result connection_type
5436  */
5437 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5438     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5439     if (!conn) return GAP_CONNECTION_INVALID;
5440     switch (conn->address_type){
5441         case BD_ADDR_TYPE_LE_PUBLIC:
5442         case BD_ADDR_TYPE_LE_RANDOM:
5443             return GAP_CONNECTION_LE;
5444         case BD_ADDR_TYPE_SCO:
5445             return GAP_CONNECTION_SCO;
5446         case BD_ADDR_TYPE_ACL:
5447             return GAP_CONNECTION_ACL;
5448         default:
5449             return GAP_CONNECTION_INVALID;
5450     }
5451 }
5452 
5453 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5454     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5455     if (!conn) return HCI_ROLE_INVALID;
5456     return (hci_role_t) conn->role;
5457 }
5458 
5459 
5460 #ifdef ENABLE_CLASSIC
5461 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5462     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5463     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5464     conn->request_role = role;
5465     hci_run();
5466     return ERROR_CODE_SUCCESS;
5467 }
5468 #endif
5469 
5470 #ifdef ENABLE_BLE
5471 
5472 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){
5473     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5474     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5475 
5476     conn->le_phy_update_all_phys    = all_phys;
5477     conn->le_phy_update_tx_phys     = tx_phys;
5478     conn->le_phy_update_rx_phys     = rx_phys;
5479     conn->le_phy_update_phy_options = phy_options;
5480 
5481     hci_run();
5482 
5483     return 0;
5484 }
5485 
5486 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5487     // check if already in list
5488     btstack_linked_list_iterator_t it;
5489     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5490     while (btstack_linked_list_iterator_has_next(&it)) {
5491         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5492         if (entry->address_type != address_type) {
5493             continue;
5494         }
5495         if (memcmp(entry->address, address, 6) != 0) {
5496             continue;
5497         }
5498 		// disallow if already scheduled to add
5499 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
5500 			return ERROR_CODE_COMMAND_DISALLOWED;
5501 		}
5502 		// still on controller, but scheduled to remove -> re-add
5503 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
5504 		return ERROR_CODE_SUCCESS;
5505     }
5506     // alloc and add to list
5507     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5508     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5509     entry->address_type = address_type;
5510     (void)memcpy(entry->address, address, 6);
5511     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5512     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5513     return ERROR_CODE_SUCCESS;
5514 }
5515 
5516 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5517     btstack_linked_list_iterator_t it;
5518     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5519     while (btstack_linked_list_iterator_has_next(&it)){
5520         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5521         if (entry->address_type != address_type) {
5522             continue;
5523         }
5524         if (memcmp(entry->address, address, 6) != 0) {
5525             continue;
5526         }
5527         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5528             // remove from controller if already present
5529             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5530         }  else {
5531             // directly remove entry from whitelist
5532             btstack_linked_list_iterator_remove(&it);
5533             btstack_memory_whitelist_entry_free(entry);
5534         }
5535         return ERROR_CODE_SUCCESS;
5536     }
5537     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5538 }
5539 
5540 static void hci_whitelist_clear(void){
5541     btstack_linked_list_iterator_t it;
5542     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5543     while (btstack_linked_list_iterator_has_next(&it)){
5544         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5545         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5546             // remove from controller if already present
5547             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5548             continue;
5549         }
5550         // directly remove entry from whitelist
5551         btstack_linked_list_iterator_remove(&it);
5552         btstack_memory_whitelist_entry_free(entry);
5553     }
5554 }
5555 
5556 /**
5557  * @brief Clear Whitelist
5558  * @returns 0 if ok
5559  */
5560 uint8_t gap_whitelist_clear(void){
5561     hci_whitelist_clear();
5562     hci_run();
5563     return ERROR_CODE_SUCCESS;
5564 }
5565 
5566 /**
5567  * @brief Add Device to Whitelist
5568  * @param address_typ
5569  * @param address
5570  * @returns 0 if ok
5571  */
5572 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5573     uint8_t status = hci_whitelist_add(address_type, address);
5574     if (status){
5575         return status;
5576     }
5577     hci_run();
5578     return ERROR_CODE_SUCCESS;
5579 }
5580 
5581 /**
5582  * @brief Remove Device from Whitelist
5583  * @param address_typ
5584  * @param address
5585  * @returns 0 if ok
5586  */
5587 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5588     uint8_t status = hci_whitelist_remove(address_type, address);
5589     if (status){
5590         return status;
5591     }
5592     hci_run();
5593     return ERROR_CODE_SUCCESS;
5594 }
5595 
5596 #ifdef ENABLE_LE_CENTRAL
5597 /**
5598  *  @brief Connect with Whitelist
5599  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5600  *  @returns - if ok
5601  */
5602 uint8_t gap_connect_with_whitelist(void){
5603     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5604         return ERROR_CODE_COMMAND_DISALLOWED;
5605     }
5606     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5607     hci_run();
5608     return ERROR_CODE_SUCCESS;
5609 }
5610 
5611 /**
5612  * @brief Auto Connection Establishment - Start Connecting to device
5613  * @param address_typ
5614  * @param address
5615  * @returns 0 if ok
5616  */
5617 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
5618     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5619         return ERROR_CODE_COMMAND_DISALLOWED;
5620     }
5621 
5622     uint8_t status = hci_whitelist_add(address_type, address);
5623     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5624         return status;
5625     }
5626 
5627     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5628 
5629     hci_run();
5630     return ERROR_CODE_SUCCESS;
5631 }
5632 
5633 /**
5634  * @brief Auto Connection Establishment - Stop Connecting to device
5635  * @param address_typ
5636  * @param address
5637  * @returns 0 if ok
5638  */
5639 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
5640     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5641         return ERROR_CODE_COMMAND_DISALLOWED;
5642     }
5643 
5644     hci_whitelist_remove(address_type, address);
5645     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5646         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5647     }
5648     hci_run();
5649     return 0;
5650 }
5651 
5652 /**
5653  * @brief Auto Connection Establishment - Stop everything
5654  * @note  Convenience function to stop all active auto connection attempts
5655  */
5656 uint8_t gap_auto_connection_stop_all(void){
5657     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5658         return ERROR_CODE_COMMAND_DISALLOWED;
5659     }
5660     hci_whitelist_clear();
5661     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5662     hci_run();
5663     return ERROR_CODE_SUCCESS;
5664 }
5665 
5666 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5667     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5668     if (!conn) return 0;
5669     return conn->le_connection_interval;
5670 }
5671 #endif
5672 #endif
5673 
5674 #ifdef ENABLE_CLASSIC
5675 /**
5676  * @brief Set Extended Inquiry Response data
5677  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5678  * @note has to be done before stack starts up
5679  */
5680 void gap_set_extended_inquiry_response(const uint8_t * data){
5681     hci_stack->eir_data = data;
5682 }
5683 
5684 /**
5685  * @brief Start GAP Classic Inquiry
5686  * @param duration in 1.28s units
5687  * @return 0 if ok
5688  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5689  */
5690 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5691     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5692     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5693     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5694         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5695     }
5696     hci_stack->inquiry_state = duration_in_1280ms_units;
5697     hci_run();
5698     return 0;
5699 }
5700 
5701 /**
5702  * @brief Stop GAP Classic Inquiry
5703  * @returns 0 if ok
5704  */
5705 int gap_inquiry_stop(void){
5706     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5707         // emit inquiry complete event, before it even started
5708         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5709         hci_emit_event(event, sizeof(event), 1);
5710         return 0;
5711     }
5712     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5713     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5714     hci_run();
5715     return 0;
5716 }
5717 
5718 
5719 /**
5720  * @brief Remote Name Request
5721  * @param addr
5722  * @param page_scan_repetition_mode
5723  * @param clock_offset only used when bit 15 is set
5724  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5725  */
5726 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5727     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5728     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5729     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5730     hci_stack->remote_name_clock_offset = clock_offset;
5731     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5732     hci_run();
5733     return 0;
5734 }
5735 
5736 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
5737     hci_stack->gap_pairing_state = state;
5738     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5739     hci_run();
5740     return 0;
5741 }
5742 
5743 /**
5744  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5745  * @param addr
5746  * @param pin_data
5747  * @param pin_len
5748  * @return 0 if ok
5749  */
5750 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5751     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5752     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5753     hci_stack->gap_pairing_pin_len = pin_len;
5754     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5755 }
5756 
5757 /**
5758  * @brief Legacy Pairing Pin Code Response
5759  * @param addr
5760  * @param pin
5761  * @return 0 if ok
5762  */
5763 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
5764     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5765 }
5766 
5767 /**
5768  * @brief Abort Legacy Pairing
5769  * @param addr
5770  * @param pin
5771  * @return 0 if ok
5772  */
5773 int gap_pin_code_negative(bd_addr_t addr){
5774     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5775     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5776 }
5777 
5778 /**
5779  * @brief SSP Passkey Response
5780  * @param addr
5781  * @param passkey
5782  * @return 0 if ok
5783  */
5784 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
5785     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5786     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5787     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5788 }
5789 
5790 /**
5791  * @brief Abort SSP Passkey Entry/Pairing
5792  * @param addr
5793  * @param pin
5794  * @return 0 if ok
5795  */
5796 int gap_ssp_passkey_negative(const bd_addr_t addr){
5797     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5798     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5799 }
5800 
5801 /**
5802  * @brief Accept SSP Numeric Comparison
5803  * @param addr
5804  * @param passkey
5805  * @return 0 if ok
5806  */
5807 int gap_ssp_confirmation_response(const bd_addr_t addr){
5808     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5809     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5810 }
5811 
5812 /**
5813  * @brief Abort SSP Numeric Comparison/Pairing
5814  * @param addr
5815  * @param pin
5816  * @return 0 if ok
5817  */
5818 int gap_ssp_confirmation_negative(const bd_addr_t addr){
5819     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5820     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5821 }
5822 
5823 /**
5824  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5825  * @param inquiry_mode see bluetooth_defines.h
5826  */
5827 void hci_set_inquiry_mode(inquiry_mode_t mode){
5828     hci_stack->inquiry_mode = mode;
5829 }
5830 
5831 /**
5832  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5833  */
5834 void hci_set_sco_voice_setting(uint16_t voice_setting){
5835     hci_stack->sco_voice_setting = voice_setting;
5836 }
5837 
5838 /**
5839  * @brief Get SCO Voice Setting
5840  * @return current voice setting
5841  */
5842 uint16_t hci_get_sco_voice_setting(void){
5843     return hci_stack->sco_voice_setting;
5844 }
5845 
5846 static int hci_have_usb_transport(void){
5847     if (!hci_stack->hci_transport) return 0;
5848     const char * transport_name = hci_stack->hci_transport->name;
5849     if (!transport_name) return 0;
5850     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5851 }
5852 
5853 /** @brief Get SCO packet length for current SCO Voice setting
5854  *  @note  Using SCO packets of the exact length is required for USB transfer
5855  *  @return Length of SCO packets in bytes (not audio frames)
5856  */
5857 int hci_get_sco_packet_length(void){
5858     int sco_packet_length = 0;
5859 
5860 #ifdef ENABLE_SCO_OVER_HCI
5861 
5862     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5863     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5864 
5865     if (hci_have_usb_transport()){
5866         // see Core Spec for H2 USB Transfer.
5867         // 3 byte SCO header + 24 bytes per connection
5868         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5869         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5870     } else {
5871         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5872         sco_packet_length = 3 + 60 * multiplier;
5873         // assert that it still fits inside an SCO buffer
5874         if (sco_packet_length > hci_stack->sco_data_packet_length){
5875             sco_packet_length = 3 + 60;
5876         }
5877     }
5878 #endif
5879     return sco_packet_length;
5880 }
5881 
5882 /**
5883 * @brief Sets the master/slave policy
5884 * @param policy (0: attempt to become master, 1: let connecting device decide)
5885 */
5886 void hci_set_master_slave_policy(uint8_t policy){
5887     hci_stack->master_slave_policy = policy;
5888 }
5889 
5890 #endif
5891 
5892 HCI_STATE hci_get_state(void){
5893     return hci_stack->state;
5894 }
5895 
5896 #ifdef ENABLE_CLASSIC
5897 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5898     hci_stack->gap_classic_accept_callback = accept_callback;
5899 }
5900 #endif
5901 
5902 /**
5903  * @brief Set callback for Bluetooth Hardware Error
5904  */
5905 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5906     hci_stack->hardware_error_callback = fn;
5907 }
5908 
5909 void hci_disconnect_all(void){
5910     btstack_linked_list_iterator_t it;
5911     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5912     while (btstack_linked_list_iterator_has_next(&it)){
5913         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5914         if (con->state == SENT_DISCONNECT) continue;
5915         con->state = SEND_DISCONNECT;
5916     }
5917     hci_run();
5918 }
5919 
5920 uint16_t hci_get_manufacturer(void){
5921     return hci_stack->manufacturer;
5922 }
5923 
5924 #ifdef ENABLE_BLE
5925 
5926 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5927     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5928     if (!hci_con) return NULL;
5929     return &hci_con->sm_connection;
5930 }
5931 
5932 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5933 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5934 
5935 int gap_encryption_key_size(hci_con_handle_t con_handle){
5936     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5937     if (hci_connection == NULL) return 0;
5938     if (hci_is_le_connection(hci_connection)){
5939         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5940         if (sm_conn->sm_connection_encrypted) {
5941             return sm_conn->sm_actual_encryption_key_size;
5942         }
5943     }
5944 #ifdef ENABLE_CLASSIC
5945     else {
5946         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5947             return hci_connection->encryption_key_size;
5948         }
5949     }
5950 #endif
5951     return 0;
5952 }
5953 
5954 int gap_authenticated(hci_con_handle_t con_handle){
5955     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5956     if (hci_connection == NULL) return 0;
5957 
5958     switch (hci_connection->address_type){
5959         case BD_ADDR_TYPE_LE_PUBLIC:
5960         case BD_ADDR_TYPE_LE_RANDOM:
5961             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5962             return hci_connection->sm_connection.sm_connection_authenticated;
5963 #ifdef ENABLE_CLASSIC
5964         case BD_ADDR_TYPE_SCO:
5965         case BD_ADDR_TYPE_ACL:
5966             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5967 #endif
5968         default:
5969             return 0;
5970     }
5971 }
5972 
5973 int gap_secure_connection(hci_con_handle_t con_handle){
5974     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5975     if (hci_connection == NULL) return 0;
5976 
5977     switch (hci_connection->address_type){
5978         case BD_ADDR_TYPE_LE_PUBLIC:
5979         case BD_ADDR_TYPE_LE_RANDOM:
5980             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5981             return hci_connection->sm_connection.sm_connection_sc;
5982 #ifdef ENABLE_CLASSIC
5983         case BD_ADDR_TYPE_SCO:
5984         case BD_ADDR_TYPE_ACL:
5985             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5986 #endif
5987         default:
5988             return 0;
5989     }
5990 }
5991 
5992 bool gap_bonded(hci_con_handle_t con_handle){
5993 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5994 	if (hci_connection == NULL) return 0;
5995 
5996 #ifdef ENABLE_CLASSIC
5997 	link_key_t link_key;
5998 	link_key_type_t link_key_type;
5999 #endif
6000 	switch (hci_connection->address_type){
6001 		case BD_ADDR_TYPE_LE_PUBLIC:
6002 		case BD_ADDR_TYPE_LE_RANDOM:
6003 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6004 #ifdef ENABLE_CLASSIC
6005 		case BD_ADDR_TYPE_SCO:
6006 		case BD_ADDR_TYPE_ACL:
6007 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6008 #endif
6009 		default:
6010 			return false;
6011 	}
6012 }
6013 
6014 
6015 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6016     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6017     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6018     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6019     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6020     return sm_conn->sm_connection_authorization_state;
6021 }
6022 #endif
6023 
6024 #ifdef ENABLE_CLASSIC
6025 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){
6026     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6027     if (!conn) return GAP_CONNECTION_INVALID;
6028     conn->sniff_min_interval = sniff_min_interval;
6029     conn->sniff_max_interval = sniff_max_interval;
6030     conn->sniff_attempt = sniff_attempt;
6031     conn->sniff_timeout = sniff_timeout;
6032     hci_run();
6033     return 0;
6034 }
6035 
6036 /**
6037  * @brief Exit Sniff mode
6038  * @param con_handle
6039  @ @return 0 if ok
6040  */
6041 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6042     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6043     if (!conn) return GAP_CONNECTION_INVALID;
6044     conn->sniff_min_interval = 0xffff;
6045     hci_run();
6046     return 0;
6047 }
6048 #endif
6049 
6050 void hci_halting_defer(void){
6051     if (hci_stack->state != HCI_STATE_HALTING) return;
6052     switch (hci_stack->substate){
6053         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6054         case HCI_HALTING_CLOSE:
6055             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6056             break;
6057         default:
6058             break;
6059     }
6060 }
6061 
6062 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6063 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6064     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6065     if (le_device_db_index >= le_device_db_max_count()) return;
6066     uint8_t offset = le_device_db_index >> 3;
6067     uint8_t mask = 1 << (le_device_db_index & 7);
6068     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6069     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6070     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6071         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6072     }
6073 }
6074 
6075 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6076 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6077 	if (le_device_db_index >= le_device_db_max_count()) return;
6078 	uint8_t offset = le_device_db_index >> 3;
6079 	uint8_t mask = 1 << (le_device_db_index & 7);
6080 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6081 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6082 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6083 	}
6084 }
6085 
6086 uint8_t gap_load_resolving_list_from_le_device_db(void){
6087 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6088 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6089 	}
6090 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6091 		// restart le resolving list update
6092 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6093 	}
6094 	return ERROR_CODE_SUCCESS;
6095 }
6096 #endif
6097 
6098 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6099 void hci_setup_test_connections_fuzz(void){
6100     hci_connection_t * conn;
6101 
6102     // default address: 66:55:44:33:00:01
6103     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6104 
6105     // setup Controller info
6106     hci_stack->num_cmd_packets = 255;
6107     hci_stack->acl_packets_total_num = 255;
6108 
6109     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6110     addr[5] = 0x01;
6111     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6112     conn->con_handle = addr[5];
6113     conn->role  = HCI_ROLE_SLAVE;
6114     conn->state = RECEIVED_CONNECTION_REQUEST;
6115     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6116 
6117     // setup incoming Classic SCO connection with con handle 0x0002
6118     addr[5] = 0x02;
6119     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6120     conn->con_handle = addr[5];
6121     conn->role  = HCI_ROLE_SLAVE;
6122     conn->state = RECEIVED_CONNECTION_REQUEST;
6123     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6124 
6125     // setup ready Classic ACL connection with con handle 0x0003
6126     addr[5] = 0x03;
6127     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6128     conn->con_handle = addr[5];
6129     conn->role  = HCI_ROLE_SLAVE;
6130     conn->state = OPEN;
6131     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6132 
6133     // setup ready Classic SCO connection with con handle 0x0004
6134     addr[5] = 0x04;
6135     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6136     conn->con_handle = addr[5];
6137     conn->role  = HCI_ROLE_SLAVE;
6138     conn->state = OPEN;
6139     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6140 
6141     // setup ready LE ACL connection with con handle 0x005 and public address
6142     addr[5] = 0x05;
6143     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6144     conn->con_handle = addr[5];
6145     conn->role  = HCI_ROLE_SLAVE;
6146     conn->state = OPEN;
6147     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6148 }
6149 
6150 void hci_free_connections_fuzz(void){
6151     btstack_linked_list_iterator_t it;
6152     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6153     while (btstack_linked_list_iterator_has_next(&it)){
6154         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6155         btstack_linked_list_iterator_remove(&it);
6156         btstack_memory_hci_connection_free(con);
6157     }
6158 }
6159 void hci_simulate_working_fuzz(void){
6160     hci_init_done();
6161     hci_stack->num_cmd_packets = 255;
6162 }
6163 #endif
6164