xref: /btstack/src/hci.c (revision cc15bb2c5415056b7b426f7c819782dac2029acf)
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 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
98 #endif
99 
100 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
101 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
102 #endif
103 
104 #define HCI_CONNECTION_TIMEOUT_MS 10000
105 
106 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
107 #define HCI_RESET_RESEND_TIMEOUT_MS 200
108 #endif
109 
110 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
111 #ifndef GAP_INQUIRY_MAX_NAME_LEN
112 #define GAP_INQUIRY_MAX_NAME_LEN 32
113 #endif
114 
115 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
116 #define GAP_INQUIRY_DURATION_MIN       0x01
117 #define GAP_INQUIRY_DURATION_MAX       0x30
118 #define GAP_INQUIRY_STATE_IDLE         0x00
119 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
120 #define GAP_INQUIRY_STATE_ACTIVE       0x81
121 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
122 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
123 
124 // GAP Remote Name Request
125 #define GAP_REMOTE_NAME_STATE_IDLE 0
126 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
127 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
128 
129 // GAP Pairing
130 #define GAP_PAIRING_STATE_IDLE                       0
131 #define GAP_PAIRING_STATE_SEND_PIN                   1
132 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
133 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
134 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
135 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
136 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
137 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
138 
139 // prototypes
140 #ifdef ENABLE_CLASSIC
141 static void hci_update_scan_enable(void);
142 static void hci_emit_discoverable_enabled(uint8_t enabled);
143 static int  hci_local_ssp_activated(void);
144 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
145 static bool hci_ssp_supported(hci_connection_t * connection);
146 static void hci_notify_if_sco_can_send_now(void);
147 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
148 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
149 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
150 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
151 static void hci_connection_timestamp(hci_connection_t *connection);
152 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
153 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
154 #endif
155 
156 static int  hci_power_control_on(void);
157 static void hci_power_control_off(void);
158 static void hci_state_reset(void);
159 static void hci_emit_transport_packet_sent(void);
160 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
161 static void hci_emit_nr_connections_changed(void);
162 static void hci_emit_hci_open_failed(void);
163 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
164 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
165 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
166 static void hci_run(void);
167 static int  hci_is_le_connection(hci_connection_t * connection);
168 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
169 
170 #ifdef ENABLE_CLASSIC
171 static int hci_have_usb_transport(void);
172 #endif
173 
174 #ifdef ENABLE_BLE
175 #ifdef ENABLE_LE_CENTRAL
176 // called from test/ble_client/advertising_data_parser.c
177 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
178 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
179 static hci_connection_t * gap_get_outgoing_connection(void);
180 #endif
181 #endif
182 
183 // the STACK is here
184 #ifndef HAVE_MALLOC
185 static hci_stack_t   hci_stack_static;
186 #endif
187 static hci_stack_t * hci_stack = NULL;
188 
189 #ifdef ENABLE_CLASSIC
190 // default name
191 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
192 
193 // test helper
194 static uint8_t disable_l2cap_timeouts = 0;
195 #endif
196 
197 /**
198  * create connection for given address
199  *
200  * @return connection OR NULL, if no memory left
201  */
202 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
203     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
204     hci_connection_t * conn = btstack_memory_hci_connection_get();
205     if (!conn) return NULL;
206     bd_addr_copy(conn->address, addr);
207     conn->role = HCI_ROLE_INVALID;
208     conn->address_type = addr_type;
209     conn->con_handle = 0xffff;
210     conn->authentication_flags = AUTH_FLAG_NONE;
211     conn->bonding_flags = 0;
212     conn->requested_security_level = LEVEL_0;
213 #ifdef ENABLE_CLASSIC
214     conn->request_role = HCI_ROLE_INVALID;
215     conn->sniff_subrating_max_latency = 0xffff;
216     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
217     conn->link_key_type = INVALID_LINK_KEY;
218     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
219     btstack_run_loop_set_timer_context(&conn->timeout, conn);
220     hci_connection_timestamp(conn);
221 #endif
222     conn->acl_recombination_length = 0;
223     conn->acl_recombination_pos = 0;
224     conn->num_packets_sent = 0;
225 
226     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
227 #ifdef ENABLE_BLE
228     conn->le_phy_update_all_phys = 0xff;
229 #endif
230 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
231     conn->le_max_tx_octets = 27;
232 #endif
233     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
234     return conn;
235 }
236 
237 
238 /**
239  * get le connection parameter range
240 *
241  * @return le connection parameter range struct
242  */
243 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
244     *range = hci_stack->le_connection_parameter_range;
245 }
246 
247 /**
248  * set le connection parameter range
249  *
250  */
251 
252 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
253     hci_stack->le_connection_parameter_range = *range;
254 }
255 
256 /**
257  * @brief Test if connection parameters are inside in existing rage
258  * @param conn_interval_min (unit: 1.25ms)
259  * @param conn_interval_max (unit: 1.25ms)
260  * @param conn_latency
261  * @param supervision_timeout (unit: 10ms)
262  * @returns 1 if included
263  */
264 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){
265     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
266     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
267 
268     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
269     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
270 
271     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
272     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
273 
274     return 1;
275 }
276 
277 /**
278  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
279  * @note: default: 1
280  * @param max_peripheral_connections
281  */
282 #ifdef ENABLE_LE_PERIPHERAL
283 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
284     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
285 }
286 #endif
287 
288 /**
289  * get hci connections iterator
290  *
291  * @return hci connections iterator
292  */
293 
294 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
295     btstack_linked_list_iterator_init(it, &hci_stack->connections);
296 }
297 
298 /**
299  * get connection for a given handle
300  *
301  * @return connection OR NULL, if not found
302  */
303 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
304     btstack_linked_list_iterator_t it;
305     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
306     while (btstack_linked_list_iterator_has_next(&it)){
307         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
308         if ( item->con_handle == con_handle ) {
309             return item;
310         }
311     }
312     return NULL;
313 }
314 
315 /**
316  * get connection for given address
317  *
318  * @return connection OR NULL, if not found
319  */
320 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
321     btstack_linked_list_iterator_t it;
322     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
323     while (btstack_linked_list_iterator_has_next(&it)){
324         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
325         if (connection->address_type != addr_type)  continue;
326         if (memcmp(addr, connection->address, 6) != 0) continue;
327         return connection;
328     }
329     return NULL;
330 }
331 
332 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
333     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
334 }
335 
336 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
337     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
338 }
339 
340 #ifdef ENABLE_CLASSIC
341 
342 #ifdef ENABLE_SCO_OVER_HCI
343 static int hci_number_sco_connections(void){
344     int connections = 0;
345     btstack_linked_list_iterator_t it;
346     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
347     while (btstack_linked_list_iterator_has_next(&it)){
348         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
349         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
350         connections++;
351     }
352     return connections;
353 }
354 #endif
355 
356 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
357     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
358 #ifdef HAVE_EMBEDDED_TICK
359     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
360         // connections might be timed out
361         hci_emit_l2cap_check_timeout(connection);
362     }
363 #else
364     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
365         // connections might be timed out
366         hci_emit_l2cap_check_timeout(connection);
367     }
368 #endif
369 }
370 
371 static void hci_connection_timestamp(hci_connection_t *connection){
372 #ifdef HAVE_EMBEDDED_TICK
373     connection->timestamp = btstack_run_loop_embedded_get_ticks();
374 #else
375     connection->timestamp = btstack_run_loop_get_time_ms();
376 #endif
377 }
378 
379 /**
380  * add authentication flags and reset timer
381  * @note: assumes classic connection
382  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
383  */
384 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
385     bd_addr_t addr;
386     reverse_bd_addr(bd_addr, addr);
387     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
388     if (conn) {
389         connectionSetAuthenticationFlags(conn, flags);
390         hci_connection_timestamp(conn);
391     }
392 }
393 
394 static bool hci_pairing_active(hci_connection_t * hci_connection){
395     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
396 }
397 
398 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
399     if (hci_pairing_active(hci_connection)) return;
400     if (ssp){
401         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
402     } else {
403         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
404     }
405     // if we are initiator, we have sent an HCI Authenticate Request
406     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
407 
408     // if we are responder, use minimal service security level as required level
409     if (!initiator){
410         hci_connection->requested_security_level = (gap_security_level_t) btstack_max((uint32_t) hci_connection->requested_security_level, (uint32_t) hci_stack->gap_minimal_service_security_level);
411     }
412 
413     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
414 
415     uint8_t event[12];
416     event[0] = GAP_EVENT_PAIRING_STARTED;
417     event[1] = 10;
418     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
419     reverse_bd_addr(hci_connection->address, &event[4]);
420     event[10] = (uint8_t) ssp;
421     event[11] = (uint8_t) initiator;
422     hci_emit_event(event, sizeof(event), 1);
423 }
424 
425 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
426     hci_connection->requested_security_level = LEVEL_0;
427     if (!hci_pairing_active(hci_connection)) return;
428     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
429     log_info("pairing complete, status %02x", status);
430 
431     uint8_t event[12];
432     event[0] = GAP_EVENT_PAIRING_COMPLETE;
433     event[1] = 9;
434     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
435     reverse_bd_addr(hci_connection->address, &event[4]);
436     event[10] = status;
437     hci_emit_event(event, sizeof(event), 1);
438 }
439 
440 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
441     hci_connection_t * conn = hci_connection_for_handle(handle);
442     if (!conn) return 0;
443     return (int) hci_pairing_active(conn);
444 }
445 
446 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
447     if (!hci_stack->link_key_db) return;
448     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
449     hci_stack->link_key_db->delete_link_key(addr);
450 }
451 
452 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
453     if (!hci_stack->link_key_db) return;
454     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
455     hci_stack->link_key_db->put_link_key(addr, link_key, type);
456 }
457 
458 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
459 	if (!hci_stack->link_key_db) return false;
460 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
461 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
462 	return result;
463 }
464 
465 void gap_delete_all_link_keys(void){
466     bd_addr_t  addr;
467     link_key_t link_key;
468     link_key_type_t type;
469     btstack_link_key_iterator_t it;
470     int ok = gap_link_key_iterator_init(&it);
471     if (!ok) {
472         log_error("could not initialize iterator");
473         return;
474     }
475     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
476         gap_drop_link_key_for_bd_addr(addr);
477     }
478     gap_link_key_iterator_done(&it);
479 }
480 
481 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
482     if (!hci_stack->link_key_db) return 0;
483     if (!hci_stack->link_key_db->iterator_init) return 0;
484     return hci_stack->link_key_db->iterator_init(it);
485 }
486 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){
487     if (!hci_stack->link_key_db) return 0;
488     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
489 }
490 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
491     if (!hci_stack->link_key_db) return;
492     hci_stack->link_key_db->iterator_done(it);
493 }
494 #endif
495 
496 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
497     switch (address_type){
498         case BD_ADDR_TYPE_LE_PUBLIC:
499         case BD_ADDR_TYPE_LE_RANDOM:
500         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
501         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
502             return true;
503         default:
504             return false;
505     }
506 }
507 
508 static int hci_is_le_connection(hci_connection_t * connection){
509     return hci_is_le_connection_type(connection->address_type);
510 }
511 
512 /**
513  * count connections
514  */
515 static int nr_hci_connections(void){
516     int count = 0;
517     btstack_linked_item_t *it;
518     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
519         count++;
520     }
521     return count;
522 }
523 
524 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
525 
526     unsigned int num_packets_sent_classic = 0;
527     unsigned int num_packets_sent_le = 0;
528 
529     btstack_linked_item_t *it;
530     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
531         hci_connection_t * connection = (hci_connection_t *) it;
532         if (hci_is_le_connection(connection)){
533             num_packets_sent_le += connection->num_packets_sent;
534         }
535         if (connection->address_type == BD_ADDR_TYPE_ACL){
536             num_packets_sent_classic += connection->num_packets_sent;
537         }
538     }
539     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
540     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
541     int free_slots_le = 0;
542 
543     if (free_slots_classic < 0){
544         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);
545         return 0;
546     }
547 
548     if (hci_stack->le_acl_packets_total_num){
549         // if we have LE slots, they are used
550         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
551         if (free_slots_le < 0){
552             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);
553             return 0;
554         }
555     } else {
556         // otherwise, classic slots are used for LE, too
557         free_slots_classic -= num_packets_sent_le;
558         if (free_slots_classic < 0){
559             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);
560             return 0;
561         }
562     }
563 
564     switch (address_type){
565         case BD_ADDR_TYPE_UNKNOWN:
566             log_error("hci_number_free_acl_slots: unknown address type");
567             return 0;
568 
569         case BD_ADDR_TYPE_ACL:
570             return free_slots_classic;
571 
572         default:
573            if (hci_stack->le_acl_packets_total_num){
574                return free_slots_le;
575            }
576            return free_slots_classic;
577     }
578 }
579 
580 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
581     // get connection type
582     hci_connection_t * connection = hci_connection_for_handle(con_handle);
583     if (!connection){
584         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
585         return 0;
586     }
587     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
588 }
589 
590 #ifdef ENABLE_CLASSIC
591 static int hci_number_free_sco_slots(void){
592     unsigned int num_sco_packets_sent  = 0;
593     btstack_linked_item_t *it;
594     if (hci_stack->synchronous_flow_control_enabled){
595         // explicit flow control
596         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
597             hci_connection_t * connection = (hci_connection_t *) it;
598             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
599             num_sco_packets_sent += connection->num_packets_sent;
600         }
601         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
602             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
603             return 0;
604         }
605         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
606     } else {
607         // implicit flow control -- TODO
608         int num_ready = 0;
609         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
610             hci_connection_t * connection = (hci_connection_t *) it;
611             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
612             if (connection->sco_tx_ready == 0) continue;
613             num_ready++;
614         }
615         return num_ready;
616     }
617 }
618 #endif
619 
620 // only used to send HCI Host Number Completed Packets
621 static int hci_can_send_comand_packet_transport(void){
622     if (hci_stack->hci_packet_buffer_reserved) return 0;
623 
624     // check for async hci transport implementations
625     if (hci_stack->hci_transport->can_send_packet_now){
626         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
627             return 0;
628         }
629     }
630     return 1;
631 }
632 
633 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
634 int hci_can_send_command_packet_now(void){
635     if (hci_can_send_comand_packet_transport() == 0) return 0;
636     return hci_stack->num_cmd_packets > 0u;
637 }
638 
639 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
640     // check for async hci transport implementations
641     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
642     return hci_stack->hci_transport->can_send_packet_now(packet_type);
643 }
644 
645 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
646     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
647     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
648 }
649 
650 int hci_can_send_acl_le_packet_now(void){
651     if (hci_stack->hci_packet_buffer_reserved) return 0;
652     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
653 }
654 
655 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
656     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
657     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
658 }
659 
660 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
661     if (hci_stack->hci_packet_buffer_reserved) return 0;
662     return hci_can_send_prepared_acl_packet_now(con_handle);
663 }
664 
665 #ifdef ENABLE_CLASSIC
666 int hci_can_send_acl_classic_packet_now(void){
667     if (hci_stack->hci_packet_buffer_reserved) return 0;
668     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
669 }
670 
671 int hci_can_send_prepared_sco_packet_now(void){
672     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
673     if (hci_have_usb_transport()){
674         return hci_stack->sco_can_send_now;
675     } else {
676         return hci_number_free_sco_slots() > 0;
677     }
678 }
679 
680 int hci_can_send_sco_packet_now(void){
681     if (hci_stack->hci_packet_buffer_reserved) return 0;
682     return hci_can_send_prepared_sco_packet_now();
683 }
684 
685 void hci_request_sco_can_send_now_event(void){
686     hci_stack->sco_waiting_for_can_send_now = 1;
687     hci_notify_if_sco_can_send_now();
688 }
689 #endif
690 
691 // used for internal checks in l2cap.c
692 int hci_is_packet_buffer_reserved(void){
693     return hci_stack->hci_packet_buffer_reserved;
694 }
695 
696 // reserves outgoing packet buffer. @returns 1 if successful
697 int hci_reserve_packet_buffer(void){
698     if (hci_stack->hci_packet_buffer_reserved) {
699         log_error("hci_reserve_packet_buffer called but buffer already reserved");
700         return 0;
701     }
702     hci_stack->hci_packet_buffer_reserved = 1;
703     return 1;
704 }
705 
706 void hci_release_packet_buffer(void){
707     hci_stack->hci_packet_buffer_reserved = 0;
708 }
709 
710 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
711 static int hci_transport_synchronous(void){
712     return hci_stack->hci_transport->can_send_packet_now == NULL;
713 }
714 
715 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
716 
717     // 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);
718 
719     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
720     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
721     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
722         max_acl_data_packet_length = hci_stack->le_data_packets_length;
723     }
724 
725 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
726     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
727         max_acl_data_packet_length = connection->le_max_tx_octets;
728     }
729 #endif
730 
731     log_debug("hci_send_acl_packet_fragments entered");
732 
733     int err;
734     // multiple packets could be send on a synchronous HCI transport
735     while (true){
736 
737         log_debug("hci_send_acl_packet_fragments loop entered");
738 
739         // get current data
740         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
741         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
742         bool more_fragments = false;
743 
744         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
745         if (current_acl_data_packet_length > max_acl_data_packet_length){
746             more_fragments = true;
747             current_acl_data_packet_length = max_acl_data_packet_length;
748         }
749 
750         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
751         if (acl_header_pos > 0u){
752             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
753             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
754             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
755         }
756 
757         // update header len
758         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
759 
760         // count packet
761         connection->num_packets_sent++;
762         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
763 
764         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
765         if (more_fragments){
766             // update start of next fragment to send
767             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
768         } else {
769             // done
770             hci_stack->acl_fragmentation_pos = 0;
771             hci_stack->acl_fragmentation_total_size = 0;
772         }
773 
774         // send packet
775         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
776         const int size = current_acl_data_packet_length + 4;
777         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
778         hci_stack->acl_fragmentation_tx_active = 1;
779         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
780 
781         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
782 
783         // done yet?
784         if (!more_fragments) break;
785 
786         // can send more?
787         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
788     }
789 
790     log_debug("hci_send_acl_packet_fragments loop over");
791 
792     // release buffer now for synchronous transport
793     if (hci_transport_synchronous()){
794         hci_stack->acl_fragmentation_tx_active = 0;
795         hci_release_packet_buffer();
796         hci_emit_transport_packet_sent();
797     }
798 
799     return err;
800 }
801 
802 // pre: caller has reserved the packet buffer
803 int hci_send_acl_packet_buffer(int size){
804 
805     // log_info("hci_send_acl_packet_buffer size %u", size);
806 
807     if (!hci_stack->hci_packet_buffer_reserved) {
808         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
809         return 0;
810     }
811 
812     uint8_t * packet = hci_stack->hci_packet_buffer;
813     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
814 
815     // check for free places on Bluetooth module
816     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
817         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
818         hci_release_packet_buffer();
819         hci_emit_transport_packet_sent();
820         return BTSTACK_ACL_BUFFERS_FULL;
821     }
822 
823     hci_connection_t *connection = hci_connection_for_handle( con_handle);
824     if (!connection) {
825         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
826         hci_release_packet_buffer();
827         hci_emit_transport_packet_sent();
828         return 0;
829     }
830 
831 #ifdef ENABLE_CLASSIC
832     hci_connection_timestamp(connection);
833 #endif
834 
835     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
836 
837     // setup data
838     hci_stack->acl_fragmentation_total_size = size;
839     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
840 
841     return hci_send_acl_packet_fragments(connection);
842 }
843 
844 #ifdef ENABLE_CLASSIC
845 // pre: caller has reserved the packet buffer
846 int hci_send_sco_packet_buffer(int size){
847 
848     // log_info("hci_send_acl_packet_buffer size %u", size);
849 
850     if (!hci_stack->hci_packet_buffer_reserved) {
851         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
852         return 0;
853     }
854 
855     uint8_t * packet = hci_stack->hci_packet_buffer;
856 
857     // skip checks in loopback mode
858     if (!hci_stack->loopback_mode){
859         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
860 
861         // check for free places on Bluetooth module
862         if (!hci_can_send_prepared_sco_packet_now()) {
863             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
864             hci_release_packet_buffer();
865             hci_emit_transport_packet_sent();
866             return BTSTACK_ACL_BUFFERS_FULL;
867         }
868 
869         // track send packet in connection struct
870         hci_connection_t *connection = hci_connection_for_handle( con_handle);
871         if (!connection) {
872             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
873             hci_release_packet_buffer();
874             hci_emit_transport_packet_sent();
875             return 0;
876         }
877 
878         if (hci_have_usb_transport()){
879             // token used
880             hci_stack->sco_can_send_now = 0;
881         } else {
882             if (hci_stack->synchronous_flow_control_enabled){
883                 connection->num_packets_sent++;
884             } else {
885                 connection->sco_tx_ready--;
886             }
887         }
888     }
889 
890     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
891 
892 #ifdef HAVE_SCO_TRANSPORT
893     hci_stack->sco_transport->send_packet(packet, size);
894     hci_release_packet_buffer();
895     hci_emit_transport_packet_sent();
896 
897     return 0;
898 #else
899     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
900     if (hci_transport_synchronous()){
901         hci_release_packet_buffer();
902         hci_emit_transport_packet_sent();
903     }
904 
905     return err;
906 #endif
907 }
908 #endif
909 
910 static void acl_handler(uint8_t *packet, uint16_t size){
911 
912     // get info
913     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
914     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
915     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
916     uint16_t acl_length         = READ_ACL_LENGTH(packet);
917 
918     // ignore non-registered handle
919     if (!conn){
920         log_error("acl_handler called with non-registered handle %u!" , con_handle);
921         return;
922     }
923 
924     // assert packet is complete
925     if ((acl_length + 4u) != size){
926         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
927         return;
928     }
929 
930 #ifdef ENABLE_CLASSIC
931     // update idle timestamp
932     hci_connection_timestamp(conn);
933 #endif
934 
935 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
936     hci_stack->host_completed_packets = 1;
937     conn->num_packets_completed++;
938 #endif
939 
940     // handle different packet types
941     switch (acl_flags & 0x03u) {
942 
943         case 0x01: // continuation fragment
944 
945             // sanity checks
946             if (conn->acl_recombination_pos == 0u) {
947                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
948                 return;
949             }
950             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
951                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
952                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
953                 conn->acl_recombination_pos = 0;
954                 return;
955             }
956 
957             // append fragment payload (header already stored)
958             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
959                          &packet[4], acl_length);
960             conn->acl_recombination_pos += acl_length;
961 
962             // forward complete L2CAP packet if complete.
963             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
964                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
965                 // reset recombination buffer
966                 conn->acl_recombination_length = 0;
967                 conn->acl_recombination_pos = 0;
968             }
969             break;
970 
971         case 0x02: { // first fragment
972 
973             // sanity check
974             if (conn->acl_recombination_pos) {
975                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
976                 conn->acl_recombination_pos = 0;
977             }
978 
979             // peek into L2CAP packet!
980             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
981 
982             // compare fragment size to L2CAP packet size
983             if (acl_length >= (l2cap_length + 4u)){
984                 // forward fragment as L2CAP packet
985                 hci_emit_acl_packet(packet, acl_length + 4u);
986             } else {
987 
988                 if (acl_length > HCI_ACL_BUFFER_SIZE){
989                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
990                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
991                     return;
992                 }
993 
994                 // store first fragment and tweak acl length for complete package
995                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
996                              packet, acl_length + 4u);
997                 conn->acl_recombination_pos    = acl_length + 4u;
998                 conn->acl_recombination_length = l2cap_length;
999                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1000             }
1001             break;
1002 
1003         }
1004         default:
1005             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1006             return;
1007     }
1008 
1009     // execute main loop
1010     hci_run();
1011 }
1012 
1013 static void hci_shutdown_connection(hci_connection_t *conn){
1014     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1015 
1016 #ifdef ENABLE_CLASSIC
1017 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1018     bd_addr_type_t addr_type = conn->address_type;
1019 #endif
1020 #ifdef HAVE_SCO_TRANSPORT
1021     hci_con_handle_t con_handle = conn->con_handle;
1022 #endif
1023 #endif
1024 
1025     btstack_run_loop_remove_timer(&conn->timeout);
1026 
1027     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1028     btstack_memory_hci_connection_free( conn );
1029 
1030     // now it's gone
1031     hci_emit_nr_connections_changed();
1032 
1033 #ifdef ENABLE_CLASSIC
1034 #ifdef ENABLE_SCO_OVER_HCI
1035     // update SCO
1036     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1037         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1038     }
1039 #endif
1040 #ifdef HAVE_SCO_TRANSPORT
1041     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1042         hci_stack->sco_transport->close(con_handle);
1043     }
1044 #endif
1045 #endif
1046 }
1047 
1048 #ifdef ENABLE_CLASSIC
1049 
1050 static const uint16_t packet_type_sizes[] = {
1051     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1052     HCI_ACL_DH1_SIZE, 0, 0, 0,
1053     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1054     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1055 };
1056 static const uint8_t  packet_type_feature_requirement_bit[] = {
1057      0, // 3 slot packets
1058      1, // 5 slot packets
1059     25, // EDR 2 mpbs
1060     26, // EDR 3 mbps
1061     39, // 3 slot EDR packts
1062     40, // 5 slot EDR packet
1063 };
1064 static const uint16_t packet_type_feature_packet_mask[] = {
1065     0x0f00, // 3 slot packets
1066     0xf000, // 5 slot packets
1067     0x1102, // EDR 2 mpbs
1068     0x2204, // EDR 3 mbps
1069     0x0300, // 3 slot EDR packts
1070     0x3000, // 5 slot EDR packet
1071 };
1072 
1073 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1074     // enable packet types based on size
1075     uint16_t packet_types = 0;
1076     unsigned int i;
1077     for (i=0;i<16;i++){
1078         if (packet_type_sizes[i] == 0) continue;
1079         if (packet_type_sizes[i] <= buffer_size){
1080             packet_types |= 1 << i;
1081         }
1082     }
1083     // disable packet types due to missing local supported features
1084     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1085         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1086         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1087         if (feature_set) continue;
1088         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1089         packet_types &= ~packet_type_feature_packet_mask[i];
1090     }
1091     // flip bits for "may not be used"
1092     packet_types ^= 0x3306;
1093     return packet_types;
1094 }
1095 
1096 uint16_t hci_usable_acl_packet_types(void){
1097     return hci_stack->packet_types;
1098 }
1099 #endif
1100 
1101 uint8_t* hci_get_outgoing_packet_buffer(void){
1102     // hci packet buffer is >= acl data packet length
1103     return hci_stack->hci_packet_buffer;
1104 }
1105 
1106 uint16_t hci_max_acl_data_packet_length(void){
1107     return hci_stack->acl_data_packet_length;
1108 }
1109 
1110 #ifdef ENABLE_CLASSIC
1111 int hci_extended_sco_link_supported(void){
1112     // No. 31, byte 3, bit 7
1113     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1114 }
1115 #endif
1116 
1117 int hci_non_flushable_packet_boundary_flag_supported(void){
1118     // No. 54, byte 6, bit 6
1119     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1120 }
1121 
1122 static int gap_ssp_supported(void){
1123     // No. 51, byte 6, bit 3
1124     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1125 }
1126 
1127 static int hci_classic_supported(void){
1128 #ifdef ENABLE_CLASSIC
1129     // No. 37, byte 4, bit 5, = No BR/EDR Support
1130     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1131 #else
1132     return 0;
1133 #endif
1134 }
1135 
1136 static int hci_le_supported(void){
1137 #ifdef ENABLE_BLE
1138     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1139     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1140 #else
1141     return 0;
1142 #endif
1143 }
1144 
1145 #ifdef ENABLE_BLE
1146 
1147 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1148     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1149         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1150     } else {
1151         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1152     }
1153 }
1154 
1155 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1156     *addr_type = hci_stack->le_own_addr_type;
1157     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1158 }
1159 
1160 #ifdef ENABLE_LE_PERIPHERAL
1161 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1162     *addr_type = hci_stack->le_advertisements_own_addr_type;
1163     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1164 };
1165 #endif
1166 
1167 #ifdef ENABLE_LE_CENTRAL
1168 
1169 /**
1170  * @brief Get own addr type and address used for LE connections (Central)
1171  */
1172 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1173     *addr_type = hci_stack->le_connection_own_addr_type;
1174     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1175 }
1176 
1177 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1178 
1179     int offset = 3;
1180     int num_reports = packet[offset];
1181     offset += 1;
1182 
1183     int i;
1184     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1185     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1186     for (i=0; (i<num_reports) && (offset < size);i++){
1187         // sanity checks on data_length:
1188         uint8_t data_length = packet[offset + 8];
1189         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1190         if ((offset + 9u + data_length + 1u) > size)    return;
1191         // setup event
1192         uint8_t event_size = 10u + data_length;
1193         int pos = 0;
1194         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1195         event[pos++] = event_size;
1196         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1197         offset += 8;
1198         pos += 8;
1199         event[pos++] = packet[offset + 1 + data_length]; // rssi
1200         event[pos++] = data_length;
1201         offset++;
1202         (void)memcpy(&event[pos], &packet[offset], data_length);
1203         pos +=    data_length;
1204         offset += data_length + 1u; // rssi
1205         hci_emit_event(event, pos, 1);
1206     }
1207 }
1208 #endif
1209 #endif
1210 
1211 #ifdef ENABLE_BLE
1212 #ifdef ENABLE_LE_PERIPHERAL
1213 static void hci_update_advertisements_enabled_for_current_roles(void){
1214     if (hci_stack->le_advertisements_enabled){
1215         // get number of active le slave connections
1216         int num_slave_connections = 0;
1217         btstack_linked_list_iterator_t it;
1218         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1219         while (btstack_linked_list_iterator_has_next(&it)){
1220             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1221             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1222             if (con->state != OPEN) continue;
1223             if (con->role  != HCI_ROLE_SLAVE) continue;
1224             if (!hci_is_le_connection(con)) continue;
1225             num_slave_connections++;
1226         }
1227         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1228         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1229     } else {
1230         hci_stack->le_advertisements_enabled_for_current_roles = false;
1231     }
1232 }
1233 #endif
1234 #endif
1235 
1236 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1237 
1238 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1239     if (!hci_stack->config) return 0;
1240     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1241     // Limit baud rate for Broadcom chipsets to 3 mbps
1242     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1243         baud_rate = 3000000;
1244     }
1245     return baud_rate;
1246 }
1247 
1248 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1249     UNUSED(ds);
1250 
1251     switch (hci_stack->substate){
1252         case HCI_INIT_W4_SEND_RESET:
1253             log_info("Resend HCI Reset");
1254             hci_stack->substate = HCI_INIT_SEND_RESET;
1255             hci_stack->num_cmd_packets = 1;
1256             hci_run();
1257             break;
1258         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1259             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1260             if (hci_stack->hci_transport->reset_link){
1261                 hci_stack->hci_transport->reset_link();
1262             }
1263 
1264             /* fall through */
1265 
1266         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1267             log_info("Resend HCI Reset - CSR Warm Boot");
1268             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1269             hci_stack->num_cmd_packets = 1;
1270             hci_run();
1271             break;
1272         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1273             if (hci_stack->hci_transport->set_baudrate){
1274                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1275                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1276                 hci_stack->hci_transport->set_baudrate(baud_rate);
1277             }
1278             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1279             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1280                 if (hci_stack->hci_transport->reset_link){
1281                     log_info("Link Reset");
1282                     hci_stack->hci_transport->reset_link();
1283                 }
1284                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1285                 hci_run();
1286             }
1287             break;
1288         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1289             // otherwise continue
1290             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1291             hci_send_cmd(&hci_read_local_supported_commands);
1292             break;
1293         default:
1294             break;
1295     }
1296 }
1297 #endif
1298 
1299 static void hci_initializing_next_state(void){
1300     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1301 }
1302 
1303 // assumption: hci_can_send_command_packet_now() == true
1304 static void hci_initializing_run(void){
1305     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1306     switch (hci_stack->substate){
1307         case HCI_INIT_SEND_RESET:
1308             hci_state_reset();
1309 
1310 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1311             // prepare reset if command complete not received in 100ms
1312             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1313             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1314             btstack_run_loop_add_timer(&hci_stack->timeout);
1315 #endif
1316             // send command
1317             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1318             hci_send_cmd(&hci_reset);
1319             break;
1320         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1321             hci_send_cmd(&hci_read_local_version_information);
1322             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1323             break;
1324         case HCI_INIT_SEND_READ_LOCAL_NAME:
1325             hci_send_cmd(&hci_read_local_name);
1326             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1327             break;
1328 
1329 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1330         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1331             hci_state_reset();
1332             // prepare reset if command complete not received in 100ms
1333             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1334             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1335             btstack_run_loop_add_timer(&hci_stack->timeout);
1336             // send command
1337             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1338             hci_send_cmd(&hci_reset);
1339             break;
1340         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1341             hci_state_reset();
1342             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1343             hci_send_cmd(&hci_reset);
1344             break;
1345         case HCI_INIT_SEND_BAUD_CHANGE: {
1346             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1347             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1348             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1349             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1350             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1351             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1352             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1353             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1354                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1355                 btstack_run_loop_add_timer(&hci_stack->timeout);
1356             }
1357             break;
1358         }
1359         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1360             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1361             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1362             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1363             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1364             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1365             break;
1366         }
1367         case HCI_INIT_CUSTOM_INIT:
1368             // Custom initialization
1369             if (hci_stack->chipset && hci_stack->chipset->next_command){
1370                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1371                 bool send_cmd = false;
1372                 switch (hci_stack->chipset_result){
1373                     case BTSTACK_CHIPSET_VALID_COMMAND:
1374                         send_cmd = true;
1375                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1376                         break;
1377                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1378                         send_cmd = true;
1379                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1380                         log_info("CSR Warm Boot");
1381                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1382                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1383                         btstack_run_loop_add_timer(&hci_stack->timeout);
1384                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1385                             && hci_stack->config
1386                             && hci_stack->chipset
1387                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1388                             && hci_stack->hci_transport->set_baudrate
1389                             && hci_transport_uart_get_main_baud_rate()){
1390                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1391                         } else {
1392                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1393                         }
1394                         break;
1395                     default:
1396                         break;
1397                 }
1398 
1399                 if (send_cmd){
1400                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1401                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1402                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1403                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1404                     break;
1405                 }
1406                 log_info("Init script done");
1407 
1408                 // Init script download on Broadcom chipsets causes:
1409                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1410                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1411                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1412 
1413                     // - baud rate to reset, restore UART baud rate if needed
1414                     int need_baud_change = hci_stack->config
1415                         && hci_stack->chipset
1416                         && hci_stack->chipset->set_baudrate_command
1417                         && hci_stack->hci_transport->set_baudrate
1418                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1419                     if (need_baud_change) {
1420                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1421                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1422                         hci_stack->hci_transport->set_baudrate(baud_rate);
1423                     }
1424 
1425                     uint16_t bcm_delay_ms = 300;
1426                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1427                     //   -> Work around: wait here.
1428                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1429                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1430                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1431                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1432                     btstack_run_loop_add_timer(&hci_stack->timeout);
1433                     break;
1434                 }
1435             }
1436             // otherwise continue
1437             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1438             hci_send_cmd(&hci_read_local_supported_commands);
1439             break;
1440         case HCI_INIT_SET_BD_ADDR:
1441             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1442             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1443             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1444             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1445             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1446             break;
1447 #endif
1448 
1449         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1450             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1451             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1452             hci_send_cmd(&hci_read_local_supported_commands);
1453             break;
1454         case HCI_INIT_READ_BD_ADDR:
1455             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1456             hci_send_cmd(&hci_read_bd_addr);
1457             break;
1458         case HCI_INIT_READ_BUFFER_SIZE:
1459             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1460             hci_send_cmd(&hci_read_buffer_size);
1461             break;
1462         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1463             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1464             hci_send_cmd(&hci_read_local_supported_features);
1465             break;
1466 
1467 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1468         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1469             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1470             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1471             break;
1472         case HCI_INIT_HOST_BUFFER_SIZE:
1473             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1474             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1475                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1476             break;
1477 #endif
1478 
1479         case HCI_INIT_SET_EVENT_MASK:
1480             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1481             if (hci_le_supported()){
1482                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1483             } else {
1484                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1485                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1486             }
1487             break;
1488 
1489 #ifdef ENABLE_CLASSIC
1490         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1491             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1492             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1493             break;
1494         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1495             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1496             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1497             break;
1498         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1499             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1500             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1501             break;
1502         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1503             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1504             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1505             break;
1506         case HCI_INIT_WRITE_LOCAL_NAME: {
1507             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1508             hci_reserve_packet_buffer();
1509             uint8_t * packet = hci_stack->hci_packet_buffer;
1510             // construct HCI Command and send
1511             uint16_t opcode = hci_write_local_name.opcode;
1512             hci_stack->last_cmd_opcode = opcode;
1513             packet[0] = opcode & 0xff;
1514             packet[1] = opcode >> 8;
1515             packet[2] = DEVICE_NAME_LEN;
1516             memset(&packet[3], 0, DEVICE_NAME_LEN);
1517             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1518             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1519             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1520             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1521             // expand '00:00:00:00:00:00' in name with bd_addr
1522             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1523             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1524             break;
1525         }
1526         case HCI_INIT_WRITE_EIR_DATA: {
1527             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1528             hci_reserve_packet_buffer();
1529             uint8_t * packet = hci_stack->hci_packet_buffer;
1530             // construct HCI Command in-place and send
1531             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1532             hci_stack->last_cmd_opcode = opcode;
1533             uint16_t offset = 0;
1534             packet[offset++] = opcode & 0xff;
1535             packet[offset++] = opcode >> 8;
1536             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1537             packet[offset++] = 0;  // FEC not required
1538             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1539             if (hci_stack->eir_data){
1540                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1541                 ad_context_t context;
1542                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1543                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1544                     uint8_t size        = ad_iterator_get_data_len(&context);
1545                     const uint8_t *data = ad_iterator_get_data(&context);
1546                     // copy item
1547                     packet[offset++] = size + 1;
1548                     packet[offset++] = data_type;
1549                     memcpy(&packet[offset], data, size);
1550                     // update name item
1551                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1552                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1553                     }
1554                     offset += size;
1555                 }
1556             } else {
1557                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1558                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1559                 packet[offset++] = bytes_to_copy + 1;
1560                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1561                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1562                 // expand '00:00:00:00:00:00' in name with bd_addr
1563                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1564             }
1565             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1566             break;
1567         }
1568         case HCI_INIT_WRITE_INQUIRY_MODE:
1569             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1570             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1571             break;
1572         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1573             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1574 			hci_stack->secure_connections_active = true;
1575             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1576             break;
1577         case HCI_INIT_WRITE_SCAN_ENABLE:
1578             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1579             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1580             break;
1581         // only sent if ENABLE_SCO_OVER_HCI is defined
1582         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1583             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1584             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1585             break;
1586         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1587             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1588             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1589             break;
1590         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1591         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1592             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1593 #ifdef ENABLE_SCO_OVER_HCI
1594             log_info("BCM: Route SCO data via HCI transport");
1595             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1596 #endif
1597 #ifdef ENABLE_SCO_OVER_PCM
1598             log_info("BCM: Route SCO data via PCM interface");
1599 #ifdef ENABLE_BCM_PCM_WBS
1600             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1601             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1602 #else
1603             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1604             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1605 #endif
1606 #endif
1607             break;
1608 #ifdef ENABLE_SCO_OVER_PCM
1609         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1610             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1611             log_info("BCM: Config PCM interface for I2S");
1612 #ifdef ENABLE_BCM_PCM_WBS
1613             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1614             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1615 #else
1616             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1617             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1618 #endif
1619             break;
1620 #endif
1621 #endif
1622 
1623 #ifdef ENABLE_BLE
1624         // LE INIT
1625         case HCI_INIT_LE_READ_BUFFER_SIZE:
1626             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1627             hci_send_cmd(&hci_le_read_buffer_size);
1628             break;
1629         case HCI_INIT_LE_SET_EVENT_MASK:
1630             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1631             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1632             break;
1633         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1634             // LE Supported Host = 1, Simultaneous Host = 0
1635             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1636             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1637             break;
1638 #endif
1639 
1640 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1641         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1642             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1643             hci_send_cmd(&hci_le_read_maximum_data_length);
1644             break;
1645         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1646             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1647             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1648             break;
1649 #endif
1650 
1651 #ifdef ENABLE_LE_CENTRAL
1652         case HCI_INIT_READ_WHITE_LIST_SIZE:
1653             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1654             hci_send_cmd(&hci_le_read_white_list_size);
1655             break;
1656         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1657             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1658             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);
1659             break;
1660 #endif
1661         default:
1662             return;
1663     }
1664 }
1665 
1666 static void hci_init_done(void){
1667     // done. tell the app
1668     log_info("hci_init_done -> HCI_STATE_WORKING");
1669     hci_stack->state = HCI_STATE_WORKING;
1670     hci_emit_state();
1671     hci_run();
1672 }
1673 
1674 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1675     bool command_completed = false;
1676     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1677         uint16_t opcode = little_endian_read_16(packet,3);
1678         if (opcode == hci_stack->last_cmd_opcode){
1679             command_completed = true;
1680             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1681         } else {
1682             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1683         }
1684     }
1685 
1686     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1687         uint8_t  status = packet[2];
1688         uint16_t opcode = little_endian_read_16(packet,4);
1689         if (opcode == hci_stack->last_cmd_opcode){
1690             if (status){
1691                 command_completed = true;
1692                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1693             } else {
1694                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1695             }
1696         } else {
1697             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1698         }
1699     }
1700 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1701     // Vendor == CSR
1702     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1703         // TODO: track actual command
1704         command_completed = true;
1705     }
1706 
1707     // Vendor == Toshiba
1708     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1709         // TODO: track actual command
1710         command_completed = true;
1711         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1712         hci_stack->num_cmd_packets = 1;
1713     }
1714 #endif
1715 
1716     return command_completed;
1717 }
1718 
1719 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1720 
1721     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1722 
1723     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1724 
1725 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1726 
1727     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1728     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1729     //
1730     // HCI Reset
1731     // Timeout 100 ms
1732     // HCI Reset
1733     // Command Complete Reset
1734     // HCI Read Local Version Information
1735     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1736     // hang...
1737     //
1738     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1739     if (!command_completed
1740             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1741             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1742 
1743         uint16_t opcode = little_endian_read_16(packet,3);
1744         if (opcode == hci_reset.opcode){
1745             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1746             return;
1747         }
1748     }
1749 
1750     // CSR & H5
1751     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1752     if (!command_completed
1753             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1754             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1755 
1756         uint16_t opcode = little_endian_read_16(packet,3);
1757         if (opcode == hci_reset.opcode){
1758             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1759             return;
1760         }
1761     }
1762 
1763     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1764     // fix: Correct substate and behave as command below
1765     if (command_completed){
1766         switch (hci_stack->substate){
1767             case HCI_INIT_SEND_RESET:
1768                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1769                 break;
1770             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1771                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1772                 break;
1773             default:
1774                 break;
1775         }
1776     }
1777 
1778 #endif
1779 
1780     if (!command_completed) return;
1781 
1782     bool need_baud_change = false;
1783     bool need_addr_change = false;
1784 
1785 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1786     need_baud_change = hci_stack->config
1787                         && hci_stack->chipset
1788                         && hci_stack->chipset->set_baudrate_command
1789                         && hci_stack->hci_transport->set_baudrate
1790                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1791 
1792     need_addr_change = hci_stack->custom_bd_addr_set
1793                         && hci_stack->chipset
1794                         && hci_stack->chipset->set_bd_addr_command;
1795 #endif
1796 
1797     switch(hci_stack->substate){
1798 
1799 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1800         case HCI_INIT_SEND_RESET:
1801             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1802             // fix: just correct substate and behave as command below
1803             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1804             btstack_run_loop_remove_timer(&hci_stack->timeout);
1805             break;
1806         case HCI_INIT_W4_SEND_RESET:
1807             btstack_run_loop_remove_timer(&hci_stack->timeout);
1808             break;
1809         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1810             log_info("Received local name, need baud change %d", (int) need_baud_change);
1811             if (need_baud_change){
1812                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1813                 return;
1814             }
1815             // skip baud change
1816             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1817             return;
1818         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1819             // for STLC2500D, baud rate change already happened.
1820             // for others, baud rate gets changed now
1821             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1822                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1823                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1824                 hci_stack->hci_transport->set_baudrate(baud_rate);
1825             }
1826             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1827             return;
1828         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1829             btstack_run_loop_remove_timer(&hci_stack->timeout);
1830             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1831             return;
1832         case HCI_INIT_W4_CUSTOM_INIT:
1833             // repeat custom init
1834             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1835             return;
1836 #else
1837         case HCI_INIT_W4_SEND_RESET:
1838             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1839             return ;
1840 #endif
1841 
1842         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1843             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1844               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1845                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1846                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1847                 return;
1848             }
1849             if (need_addr_change){
1850                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1851                 return;
1852             }
1853             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1854             return;
1855 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1856         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1857             if (need_baud_change){
1858                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1859                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1860                 hci_stack->hci_transport->set_baudrate(baud_rate);
1861             }
1862             if (need_addr_change){
1863                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1864                 return;
1865             }
1866             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1867             return;
1868         case HCI_INIT_W4_SET_BD_ADDR:
1869             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1870             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1871             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1872                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1873                 return;
1874             }
1875             // skipping st warm boot
1876             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1877             return;
1878         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1879             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1880             return;
1881 #endif
1882         case HCI_INIT_W4_READ_BD_ADDR:
1883             // only read buffer size if supported
1884             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1885                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1886                 return;
1887             }
1888             // skipping read buffer size
1889             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1890             return;
1891         case HCI_INIT_W4_SET_EVENT_MASK:
1892             // skip Classic init commands for LE only chipsets
1893             if (!hci_classic_supported()){
1894 #ifdef ENABLE_BLE
1895                 if (hci_le_supported()){
1896                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1897                     return;
1898                 }
1899 #endif
1900                 log_error("Neither BR/EDR nor LE supported");
1901                 hci_init_done();
1902                 return;
1903             }
1904             if (!gap_ssp_supported()){
1905                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1906                 return;
1907             }
1908             break;
1909 #ifdef ENABLE_BLE
1910         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1911             // skip write le host if not supported (e.g. on LE only EM9301)
1912             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1913             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1914             return;
1915 
1916 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1917         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1918             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1919             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1920                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1921                 return;
1922             }
1923             // explicit fall through to reduce repetitions
1924 
1925 #ifdef ENABLE_LE_CENTRAL
1926             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1927 #else
1928             hci_init_done();
1929 #endif
1930             return;
1931 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1932 
1933 #endif  /* ENABLE_BLE */
1934 
1935         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1936             // skip write secure connections host support if not supported or disabled
1937             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1938                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1939                 return;
1940             }
1941             break;
1942 
1943 #ifdef ENABLE_SCO_OVER_HCI
1944         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1945             // skip write synchronous flow control if not supported
1946             if (hci_stack->local_supported_commands[0] & 0x04) break;
1947             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1948 
1949             /* fall through */
1950 
1951         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1952             // skip write default erroneous data reporting if not supported
1953             if (hci_stack->local_supported_commands[0] & 0x08) break;
1954             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1955 
1956             /* fall through */
1957 
1958         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1959             // skip bcm set sco pcm config on non-Broadcom chipsets
1960             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1961             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1962 
1963             /* fall through */
1964 
1965         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1966             if (!hci_le_supported()){
1967                 // SKIP LE init for Classic only configuration
1968                 hci_init_done();
1969                 return;
1970             }
1971             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1972             break;
1973 
1974 #else /* !ENABLE_SCO_OVER_HCI */
1975 
1976         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1977 #ifdef ENABLE_SCO_OVER_PCM
1978             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1979                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1980                 return;
1981             }
1982 #endif
1983             /* fall through */
1984 
1985         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1986 #ifdef ENABLE_BLE
1987             if (hci_le_supported()){
1988                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1989                 return;
1990             }
1991 #endif
1992             // SKIP LE init for Classic only configuration
1993             hci_init_done();
1994             return;
1995 #endif /* ENABLE_SCO_OVER_HCI */
1996 
1997 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1998 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1999         // Response to command before init done state -> init done
2000         case (HCI_INIT_DONE-1):
2001             hci_init_done();
2002             return;
2003 #endif
2004 
2005         default:
2006             break;
2007     }
2008     hci_initializing_next_state();
2009 }
2010 
2011 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2012     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2013     bd_addr_t bd_address;
2014     (void)memcpy(&bd_address, conn->address, 6);
2015 
2016 #ifdef ENABLE_CLASSIC
2017     // cache needed data
2018     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2019 #endif
2020 
2021     // connection failed, remove entry
2022     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2023     btstack_memory_hci_connection_free( conn );
2024 
2025 #ifdef ENABLE_CLASSIC
2026     // notify client if dedicated bonding
2027     if (notify_dedicated_bonding_failed){
2028         log_info("hci notify_dedicated_bonding_failed");
2029         hci_emit_dedicated_bonding_result(bd_address, status);
2030     }
2031 
2032     // if authentication error, also delete link key
2033     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2034         gap_drop_link_key_for_bd_addr(bd_address);
2035     }
2036 #else
2037     UNUSED(status);
2038 #endif
2039 }
2040 
2041 #ifdef ENABLE_CLASSIC
2042 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2043     // SSP Controller
2044     if (features[6] & (1 << 3)){
2045         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2046     }
2047     // eSCO
2048     if (features[3] & (1<<7)){
2049         conn->remote_supported_features[0] |= 1;
2050     }
2051     // Extended features
2052     if (features[7] & (1<<7)){
2053         conn->remote_supported_features[0] |= 2;
2054     }
2055 }
2056 
2057 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2058     // SSP Host
2059     if (features[0] & (1 << 0)){
2060         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2061     }
2062     // SC Host
2063     if (features[0] & (1 << 3)){
2064         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2065     }
2066 }
2067 
2068 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2069     // SC Controller
2070     if (features[1] & (1 << 0)){
2071         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2072     }
2073 }
2074 
2075 static void hci_handle_remote_features_received(hci_connection_t * conn){
2076     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2077     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2078     if (conn->bonding_flags & BONDING_DEDICATED){
2079         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2080     }
2081 }
2082 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2083     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2084     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2085 }
2086 
2087 #endif
2088 
2089 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2090     // handle BT initialization
2091     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2092         hci_initializing_event_handler(packet, size);
2093     }
2094 
2095     // help with BT sleep
2096     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2097         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2098         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2099         hci_initializing_next_state();
2100     }
2101 }
2102 
2103 #ifdef ENABLE_CLASSIC
2104 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2105     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2106     conn->encryption_key_size = encryption_key_size;
2107 
2108     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2109         conn->requested_security_level = LEVEL_0;
2110         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2111         return;
2112     }
2113 
2114     // Request Authentication if not already done
2115     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2116     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2117 }
2118 #endif
2119 
2120 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2121     UNUSED(size);
2122 
2123     uint16_t manufacturer;
2124 #ifdef ENABLE_CLASSIC
2125     hci_con_handle_t handle;
2126     hci_connection_t * conn;
2127     uint8_t status;
2128 #endif
2129     // get num cmd packets - limit to 1 to reduce complexity
2130     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2131 
2132     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2133     switch (opcode){
2134         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2135             if (packet[5]) break;
2136             // terminate, name 248 chars
2137             packet[6+248] = 0;
2138             log_info("local name: %s", &packet[6]);
2139             break;
2140         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2141             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2142             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2143                 uint16_t acl_len = little_endian_read_16(packet, 6);
2144                 uint16_t sco_len = packet[8];
2145 
2146                 // determine usable ACL/SCO payload size
2147                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2148                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2149 
2150                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2151                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2152 
2153                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2154                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2155                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2156             }
2157             break;
2158         case HCI_OPCODE_HCI_READ_RSSI:
2159             if (packet[5] == ERROR_CODE_SUCCESS){
2160                 uint8_t event[5];
2161                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2162                 event[1] = 3;
2163                 (void)memcpy(&event[2], &packet[6], 3);
2164                 hci_emit_event(event, sizeof(event), 1);
2165             }
2166             break;
2167 #ifdef ENABLE_BLE
2168         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2169             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2170             hci_stack->le_acl_packets_total_num = packet[8];
2171             // determine usable ACL payload size
2172             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2173                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2174             }
2175             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2176             break;
2177 #endif
2178 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2179         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2180             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2181             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2182             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);
2183             break;
2184 #endif
2185 #ifdef ENABLE_LE_CENTRAL
2186         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2187             hci_stack->le_whitelist_capacity = packet[6];
2188             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2189             break;
2190 #endif
2191         case HCI_OPCODE_HCI_READ_BD_ADDR:
2192             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2193             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));
2194 #ifdef ENABLE_CLASSIC
2195             if (hci_stack->link_key_db){
2196                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2197             }
2198 #endif
2199             break;
2200 #ifdef ENABLE_CLASSIC
2201         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2202             hci_emit_discoverable_enabled(hci_stack->discoverable);
2203             break;
2204         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2205             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2206                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2207                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2208                 hci_emit_event(event, sizeof(event), 1);
2209             }
2210             break;
2211 #endif
2212         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2213             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2214 
2215 #ifdef ENABLE_CLASSIC
2216             // determine usable ACL packet types based on host buffer size and supported features
2217             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2218             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2219 #endif
2220             // Classic/LE
2221             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2222             break;
2223         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2224             manufacturer = little_endian_read_16(packet, 10);
2225             // map Cypress to Broadcom
2226             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2227                 log_info("Treat Cypress as Broadcom");
2228                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2229                 little_endian_store_16(packet, 10, manufacturer);
2230             }
2231             hci_stack->manufacturer = manufacturer;
2232             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2233             break;
2234         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2235             hci_stack->local_supported_commands[0] =
2236                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2237                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2238                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2239                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2240                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2241                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2242                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2243                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2244             hci_stack->local_supported_commands[1] =
2245                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2246                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2247                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2248                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2249                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2250             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2251             break;
2252 #ifdef ENABLE_CLASSIC
2253         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2254             if (packet[5]) return;
2255             hci_stack->synchronous_flow_control_enabled = 1;
2256             break;
2257         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2258             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2259             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2260             conn   = hci_connection_for_handle(handle);
2261             if (conn != NULL) {
2262                 uint8_t key_size = 0;
2263                 if (status == 0){
2264                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2265                     log_info("Handle %04x key Size: %u", handle, key_size);
2266                 } else {
2267                     key_size = 1;
2268                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2269                 }
2270                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2271             }
2272             break;
2273         // assert pairing complete event is emitted.
2274         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2275         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2276         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2277         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2278             // lookup connection by gap pairing addr
2279             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2280             if (conn == NULL) break;
2281             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2282             break;
2283 
2284 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2285         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2286         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2287             uint8_t event[67];
2288             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2289             event[1] = 65;
2290             (void)memset(&event[2], 0, 65);
2291             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2292                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2293                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2294                     event[2] = 3;
2295                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2296                 } else {
2297                     event[2] = 1;
2298                 }
2299             }
2300             hci_emit_event(event, sizeof(event), 0);
2301             break;
2302         }
2303 #endif
2304 #endif
2305         default:
2306             break;
2307     }
2308 }
2309 
2310 #ifdef ENABLE_BLE
2311 static void event_handle_le_connection_complete(const uint8_t * packet){
2312 	bd_addr_t addr;
2313 	bd_addr_type_t addr_type;
2314 	hci_connection_t * conn;
2315 
2316 	// Connection management
2317 	reverse_bd_addr(&packet[8], addr);
2318 	addr_type = (bd_addr_type_t)packet[7];
2319 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2320 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2321 
2322 #ifdef ENABLE_LE_CENTRAL
2323 	// handle error: error is reported only to the initiator -> outgoing connection
2324 	if (packet[3]){
2325 
2326 		// handle cancelled outgoing connection
2327 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2328 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2329 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2330 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2331 		    // reset state
2332             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2333             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2334 			// get outgoing connection conn struct for direct connect
2335 			conn = gap_get_outgoing_connection();
2336 		}
2337 
2338 		// outgoing le connection establishment is done
2339 		if (conn){
2340 			// remove entry
2341 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2342 			btstack_memory_hci_connection_free( conn );
2343 		}
2344 		return;
2345 	}
2346 #endif
2347 
2348 	// on success, both hosts receive connection complete event
2349 	if (packet[6] == HCI_ROLE_MASTER){
2350 #ifdef ENABLE_LE_CENTRAL
2351 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2352 		// note: no hci_connection_t object exists yet for connect with whitelist
2353 		if (hci_is_le_connection_type(addr_type)){
2354 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2355 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2356 		}
2357 #endif
2358 	} else {
2359 #ifdef ENABLE_LE_PERIPHERAL
2360 		// if we're slave, it was an incoming connection, advertisements have stopped
2361 		hci_stack->le_advertisements_active = false;
2362 #endif
2363 	}
2364 
2365 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2366 	if (!conn){
2367 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2368 	}
2369 
2370 	// no memory, sorry.
2371 	if (!conn){
2372 		return;
2373 	}
2374 
2375 	conn->state = OPEN;
2376 	conn->role  = packet[6];
2377 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2378 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2379 
2380 #ifdef ENABLE_LE_PERIPHERAL
2381 	if (packet[6] == HCI_ROLE_SLAVE){
2382 		hci_update_advertisements_enabled_for_current_roles();
2383 	}
2384 #endif
2385 
2386     // init unenhanced att bearer mtu
2387     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2388     conn->att_connection.mtu_exchanged = false;
2389 
2390     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2391 
2392 	// restart timer
2393 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2394 	// btstack_run_loop_add_timer(&conn->timeout);
2395 
2396 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2397 
2398 	hci_emit_nr_connections_changed();
2399 }
2400 #endif
2401 
2402 #ifdef ENABLE_CLASSIC
2403 static bool hci_ssp_security_level_possible_for_io_cap(gap_security_level_t level, uint8_t io_cap_local, uint8_t io_cap_remote){
2404     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2405     // LEVEL_4 is tested by l2cap
2406     // LEVEL 3 requires MITM protection -> check io capabilities
2407     if (level >= LEVEL_3){
2408         if (io_cap_remote  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2409         if (io_cap_local   >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2410         if ((io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY) && (io_cap_local ==  SSP_IO_CAPABILITY_KEYBOARD_ONLY)) return false;
2411     }
2412     // LEVEL 2 requires SSP, which is a given
2413     return true;
2414 }
2415 
2416 static bool btstack_is_null(uint8_t * data, uint16_t size){
2417     uint16_t i;
2418     for (i=0; i < size ; i++){
2419         if (data[i] != 0) {
2420             return false;
2421         }
2422     }
2423     return true;
2424 }
2425 
2426 #endif
2427 
2428 static void event_handler(uint8_t *packet, uint16_t size){
2429 
2430     uint16_t event_length = packet[1];
2431 
2432     // assert packet is complete
2433     if (size != (event_length + 2u)){
2434         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2435         return;
2436     }
2437 
2438     bd_addr_type_t addr_type;
2439     hci_con_handle_t handle;
2440     hci_connection_t * conn;
2441     int i;
2442     int create_connection_cmd;
2443 
2444 #ifdef ENABLE_CLASSIC
2445     hci_link_type_t link_type;
2446     bd_addr_t addr;
2447 #endif
2448 
2449     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2450 
2451     switch (hci_event_packet_get_type(packet)) {
2452 
2453         case HCI_EVENT_COMMAND_COMPLETE:
2454             handle_command_complete_event(packet, size);
2455             break;
2456 
2457         case HCI_EVENT_COMMAND_STATUS:
2458             // get num cmd packets - limit to 1 to reduce complexity
2459             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2460 
2461             // check command status to detected failed outgoing connections
2462             create_connection_cmd = 0;
2463 #ifdef ENABLE_CLASSIC
2464             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2465                 create_connection_cmd = 1;
2466             }
2467 #endif
2468 #ifdef ENABLE_LE_CENTRAL
2469             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2470                 create_connection_cmd = 1;
2471             }
2472 #endif
2473             if (create_connection_cmd) {
2474                 uint8_t status = hci_event_command_status_get_status(packet);
2475                 addr_type = hci_stack->outgoing_addr_type;
2476                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2477                 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);
2478 
2479                 // reset outgoing address info
2480                 memset(hci_stack->outgoing_addr, 0, 6);
2481                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2482 
2483                 // on error
2484                 if (status != ERROR_CODE_SUCCESS){
2485 #ifdef ENABLE_LE_CENTRAL
2486                     if (hci_is_le_connection_type(addr_type)){
2487                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2488                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2489                     }
2490 #endif
2491                     // error => outgoing connection failed
2492                     if (conn != NULL){
2493                         hci_handle_connection_failed(conn, status);
2494                     }
2495                 }
2496             }
2497 
2498 #ifdef ENABLE_CLASSIC
2499             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2500                 uint8_t status = hci_event_command_status_get_status(packet);
2501                 log_info("command status (inquiry), status %x", status);
2502                 if (status == ERROR_CODE_SUCCESS) {
2503                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2504                 } else {
2505                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2506                 }
2507             }
2508 #endif
2509             break;
2510 
2511         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2512             if (size < 3) return;
2513             uint16_t num_handles = packet[2];
2514             if (size != (3u + num_handles * 4u)) return;
2515             uint16_t offset = 3;
2516             for (i=0; i<num_handles;i++){
2517                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2518                 offset += 2u;
2519                 uint16_t num_packets = little_endian_read_16(packet, offset);
2520                 offset += 2u;
2521 
2522                 conn = hci_connection_for_handle(handle);
2523                 if (!conn){
2524                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2525                     continue;
2526                 }
2527 
2528                 if (conn->num_packets_sent >= num_packets){
2529                     conn->num_packets_sent -= num_packets;
2530                 } else {
2531                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2532                     conn->num_packets_sent = 0;
2533                 }
2534                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2535 
2536 #ifdef ENABLE_CLASSIC
2537                 // For SCO, we do the can_send_now_check here
2538                 hci_notify_if_sco_can_send_now();
2539 #endif
2540             }
2541             break;
2542         }
2543 
2544 #ifdef ENABLE_CLASSIC
2545         case HCI_EVENT_INQUIRY_COMPLETE:
2546             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2547                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2548                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2549                 hci_emit_event(event, sizeof(event), 1);
2550             }
2551             break;
2552         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2553             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2554                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2555             }
2556             break;
2557         case HCI_EVENT_CONNECTION_REQUEST:
2558             reverse_bd_addr(&packet[2], addr);
2559             link_type = (hci_link_type_t) packet[11];
2560 
2561             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2562             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2563                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2564                 bd_addr_copy(hci_stack->decline_addr, addr);
2565                 break;
2566             }
2567 
2568             if (hci_stack->gap_classic_accept_callback != NULL){
2569                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2570                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2571                     bd_addr_copy(hci_stack->decline_addr, addr);
2572                     break;
2573                 }
2574             }
2575 
2576             // TODO: eval COD 8-10
2577             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2578             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2579             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2580             if (!conn) {
2581                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2582             }
2583             if (!conn) {
2584                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2585                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2586                 bd_addr_copy(hci_stack->decline_addr, addr);
2587                 break;
2588             }
2589             conn->role  = HCI_ROLE_SLAVE;
2590             conn->state = RECEIVED_CONNECTION_REQUEST;
2591             // store info about eSCO
2592             if (link_type == HCI_LINK_TYPE_ESCO){
2593                 conn->remote_supported_features[0] |= 1;
2594             }
2595             hci_run();
2596             break;
2597 
2598         case HCI_EVENT_CONNECTION_COMPLETE:
2599             // Connection management
2600             reverse_bd_addr(&packet[5], addr);
2601             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2602             addr_type = BD_ADDR_TYPE_ACL;
2603             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2604             if (conn) {
2605                 if (!packet[2]){
2606                     conn->state = OPEN;
2607                     conn->con_handle = little_endian_read_16(packet, 3);
2608 
2609                     // queue get remote feature
2610                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2611 
2612                     // queue set supervision timeout if we're master
2613                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2614                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2615                     }
2616 
2617                     // restart timer
2618                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2619                     btstack_run_loop_add_timer(&conn->timeout);
2620 
2621                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2622 
2623                     hci_emit_nr_connections_changed();
2624                 } else {
2625                     // connection failed
2626                     hci_handle_connection_failed(conn, packet[2]);
2627                 }
2628             }
2629             break;
2630 
2631         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2632             reverse_bd_addr(&packet[5], addr);
2633             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2634             if (packet[2]){
2635                 // connection failed
2636                 break;
2637             }
2638             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2639             if (!conn) {
2640                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2641             }
2642             if (!conn) {
2643                 break;
2644             }
2645             conn->state = OPEN;
2646             conn->con_handle = little_endian_read_16(packet, 3);
2647 
2648 #ifdef ENABLE_SCO_OVER_HCI
2649             // update SCO
2650             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2651                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2652             }
2653             // trigger can send now
2654             if (hci_have_usb_transport()){
2655                 hci_stack->sco_can_send_now = 1;
2656             }
2657 #endif
2658 #ifdef HAVE_SCO_TRANSPORT
2659             // configure sco transport
2660             if (hci_stack->sco_transport != NULL){
2661                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2662                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2663             }
2664 #endif
2665             break;
2666 
2667         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2668             handle = little_endian_read_16(packet, 3);
2669             conn = hci_connection_for_handle(handle);
2670             if (!conn) break;
2671             if (!packet[2]){
2672                 const uint8_t * features = &packet[5];
2673                 hci_handle_remote_features_page_0(conn, features);
2674 
2675                 // read extended features if possible
2676                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2677                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2678                     break;
2679                 }
2680             }
2681             hci_handle_remote_features_received(conn);
2682             break;
2683 
2684         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2685             handle = little_endian_read_16(packet, 3);
2686             conn = hci_connection_for_handle(handle);
2687             if (!conn) break;
2688             // status = ok, page = 1
2689             if (!packet[2]) {
2690                 uint8_t page_number = packet[5];
2691                 uint8_t maximum_page_number = packet[6];
2692                 const uint8_t * features = &packet[7];
2693                 bool done = false;
2694                 switch (page_number){
2695                     case 1:
2696                         hci_handle_remote_features_page_1(conn, features);
2697                         if (maximum_page_number >= 2){
2698                             // get Secure Connections (Controller) from Page 2 if available
2699                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2700                         } else {
2701                             // otherwise, assume SC (Controller) == SC (Host)
2702                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2703                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2704                             }
2705                             done = true;
2706                         }
2707                         break;
2708                     case 2:
2709                         hci_handle_remote_features_page_2(conn, features);
2710                         done = true;
2711                         break;
2712                     default:
2713                         break;
2714                 }
2715                 if (!done) break;
2716             }
2717             hci_handle_remote_features_received(conn);
2718             break;
2719 
2720         case HCI_EVENT_LINK_KEY_REQUEST:
2721             // request handled by hci_run()
2722             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
2723             break;
2724 
2725         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2726             hci_event_link_key_request_get_bd_addr(packet, addr);
2727             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2728             if (!conn) break;
2729 
2730             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2731 
2732             // CVE-2020-26555: ignore NULL link key
2733             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2734             if (btstack_is_null(&packet[8], 16)) break;
2735 
2736             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2737             // Change Connection Encryption keeps link key type
2738             if (link_key_type != CHANGED_COMBINATION_KEY){
2739                 conn->link_key_type = link_key_type;
2740             }
2741 
2742             // cache link key. link keys stored in little-endian format for legacy reasons
2743             memcpy(&conn->link_key, &packet[8], 16);
2744 
2745             // only store link key:
2746             // - if bondable enabled
2747             if (hci_stack->bondable == false) break;
2748             // - if security level sufficient
2749             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2750             // - for SSP, also check if remote side requested bonding as well
2751             if (conn->link_key_type != COMBINATION_KEY){
2752                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2753                 if (!remote_bonding){
2754                     break;
2755                 }
2756             }
2757             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2758             break;
2759         }
2760 
2761         case HCI_EVENT_PIN_CODE_REQUEST:
2762             hci_event_pin_code_request_get_bd_addr(packet, addr);
2763             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2764             if (!conn) break;
2765 
2766             hci_pairing_started(conn, false);
2767             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2768             if (!hci_stack->bondable ){
2769                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2770                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2771                 hci_run();
2772                 return;
2773             }
2774             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2775             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2776                 log_info("Level 4 required, but SC not supported -> abort");
2777                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2778                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2779                 hci_run();
2780                 return;
2781             }
2782             break;
2783 
2784         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2785             hci_event_io_capability_response_get_bd_addr(packet, addr);
2786             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2787             if (!conn) break;
2788 
2789             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2790             hci_pairing_started(conn, true);
2791             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2792             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2793             break;
2794 
2795         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2796             hci_event_io_capability_response_get_bd_addr(packet, addr);
2797             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2798             if (!conn) break;
2799 
2800             hci_connection_timestamp(conn);
2801 
2802             hci_pairing_started(conn, true);
2803 
2804             // assess security
2805             if ((hci_stack->gap_secure_connections_only_mode || (conn->requested_security_level == LEVEL_4)) && !hci_remote_sc_enabled(conn)){
2806                 log_info("Level 4 required, but SC not supported -> abort");
2807                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2808                 connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2809                 break;
2810             }
2811 
2812 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2813             if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2814                 connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2815             } else {
2816                 connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2817             }
2818 #endif
2819             break;
2820 
2821 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2822         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2823             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2824             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2825             if (!conn) break;
2826 
2827             hci_connection_timestamp(conn);
2828 
2829             hci_pairing_started(conn, true);
2830 
2831             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2832             break;
2833 #endif
2834 
2835         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2836             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2837             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2838             if (!conn) break;
2839             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2840                 if (hci_stack->ssp_auto_accept){
2841                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2842                 };
2843             } else {
2844                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2845                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2846                 // don't forward event to app
2847                 hci_run();
2848                 return;
2849             }
2850             break;
2851 
2852         case HCI_EVENT_USER_PASSKEY_REQUEST:
2853             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2854             if (hci_stack->ssp_auto_accept){
2855                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2856             };
2857             break;
2858 
2859         case HCI_EVENT_MODE_CHANGE:
2860             handle = hci_event_mode_change_get_handle(packet);
2861             conn = hci_connection_for_handle(handle);
2862             if (!conn) break;
2863             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2864             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2865             break;
2866 #endif
2867 
2868         case HCI_EVENT_ENCRYPTION_CHANGE:
2869             handle = hci_event_encryption_change_get_connection_handle(packet);
2870             conn = hci_connection_for_handle(handle);
2871             if (!conn) break;
2872             if (hci_event_encryption_change_get_status(packet) == 0u) {
2873                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2874                 if (encryption_enabled){
2875                     if (hci_is_le_connection(conn)){
2876                         // For LE, we accept connection as encrypted
2877                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2878                     }
2879 #ifdef ENABLE_CLASSIC
2880                     else {
2881 
2882                         // dedicated bonding: send result and disconnect
2883                         if (conn->bonding_flags & BONDING_DEDICATED){
2884                             conn->bonding_flags &= ~BONDING_DEDICATED;
2885                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2886                             conn->bonding_status = packet[2];
2887                             break;
2888                         }
2889 
2890                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2891                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2892                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2893                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2894                             log_info("SC during pairing, but only E0 now -> abort");
2895                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2896                             break;
2897                         }
2898 
2899                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2900                         if (connected_uses_aes_ccm){
2901                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
2902                         }
2903 
2904 #ifdef ENABLE_TESTING_SUPPORT
2905                         // work around for issue with PTS dongle
2906                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
2907 #endif
2908 
2909                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2910                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2911                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2912                         } else {
2913                             // if not, pretend everything is perfect
2914                             hci_handle_read_encryption_key_size_complete(conn, 16);
2915                         }
2916                     }
2917 #endif
2918                 } else {
2919                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
2920                 }
2921             }
2922 
2923             break;
2924 
2925 #ifdef ENABLE_CLASSIC
2926         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2927             handle = hci_event_authentication_complete_get_connection_handle(packet);
2928             conn = hci_connection_for_handle(handle);
2929             if (!conn) break;
2930 
2931             // clear authentication active flag
2932             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
2933             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
2934 
2935             // authenticated only if auth status == 0
2936             if (hci_event_authentication_complete_get_status(packet) == 0){
2937                 // authenticated
2938                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
2939 
2940                 // If not already encrypted, start encryption
2941                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
2942                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2943                     break;
2944                 }
2945             }
2946 
2947             // emit updated security level
2948             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2949             break;
2950 
2951         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
2952             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
2953             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2954             if (!conn) break;
2955 
2956             // treat successfully paired connection as authenticated
2957             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
2958                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
2959             }
2960 
2961             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
2962             break;
2963 #endif
2964 
2965         // HCI_EVENT_DISCONNECTION_COMPLETE
2966         // has been split, to first notify stack before shutting connection down
2967         // see end of function, too.
2968         case HCI_EVENT_DISCONNECTION_COMPLETE:
2969             if (packet[2]) break;   // status != 0
2970             handle = little_endian_read_16(packet, 3);
2971             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2972             if (hci_stack->acl_fragmentation_total_size > 0u) {
2973                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2974                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2975                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2976                     hci_stack->acl_fragmentation_total_size = 0;
2977                     hci_stack->acl_fragmentation_pos = 0;
2978                     if (release_buffer){
2979                         hci_release_packet_buffer();
2980                     }
2981                 }
2982             }
2983 
2984             conn = hci_connection_for_handle(handle);
2985             if (!conn) break;
2986 #ifdef ENABLE_CLASSIC
2987             // pairing failed if it was ongoing
2988             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
2989 #endif
2990             // mark connection for shutdown
2991             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2992 
2993             // emit dedicatd bonding event
2994             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2995                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2996             }
2997 
2998 #ifdef ENABLE_BLE
2999 #ifdef ENABLE_LE_PERIPHERAL
3000             // re-enable advertisements for le connections if active
3001             if (hci_is_le_connection(conn)){
3002                 hci_update_advertisements_enabled_for_current_roles();
3003             }
3004 #endif
3005 #endif
3006             break;
3007 
3008         case HCI_EVENT_HARDWARE_ERROR:
3009             log_error("Hardware Error: 0x%02x", packet[2]);
3010             if (hci_stack->hardware_error_callback){
3011                 (*hci_stack->hardware_error_callback)(packet[2]);
3012             } else {
3013                 // if no special requests, just reboot stack
3014                 hci_power_control_off();
3015                 hci_power_control_on();
3016             }
3017             break;
3018 
3019 #ifdef ENABLE_CLASSIC
3020         case HCI_EVENT_ROLE_CHANGE:
3021             if (packet[2]) break;   // status != 0
3022             reverse_bd_addr(&packet[3], addr);
3023             addr_type = BD_ADDR_TYPE_ACL;
3024             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3025             if (!conn) break;
3026             conn->role = packet[9];
3027             break;
3028 #endif
3029 
3030         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3031             // release packet buffer only for asynchronous transport and if there are not further fragements
3032             if (hci_transport_synchronous()) {
3033                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3034                 return; // instead of break: to avoid re-entering hci_run()
3035             }
3036             hci_stack->acl_fragmentation_tx_active = 0;
3037             if (hci_stack->acl_fragmentation_total_size) break;
3038             hci_release_packet_buffer();
3039 
3040             // L2CAP receives this event via the hci_emit_event below
3041 
3042 #ifdef ENABLE_CLASSIC
3043             // For SCO, we do the can_send_now_check here
3044             hci_notify_if_sco_can_send_now();
3045 #endif
3046             break;
3047 
3048 #ifdef ENABLE_CLASSIC
3049         case HCI_EVENT_SCO_CAN_SEND_NOW:
3050             // For SCO, we do the can_send_now_check here
3051             hci_stack->sco_can_send_now = 1;
3052             hci_notify_if_sco_can_send_now();
3053             return;
3054 
3055         // explode inquriy results for easier consumption
3056         case HCI_EVENT_INQUIRY_RESULT:
3057         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3058         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3059             gap_inquiry_explode(packet, size);
3060             break;
3061 #endif
3062 
3063 #ifdef ENABLE_BLE
3064         case HCI_EVENT_LE_META:
3065             switch (packet[2]){
3066 #ifdef ENABLE_LE_CENTRAL
3067                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3068                     // log_info("advertising report received");
3069                     if (!hci_stack->le_scanning_enabled) break;
3070                     le_handle_advertisement_report(packet, size);
3071                     break;
3072 #endif
3073                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3074 					event_handle_le_connection_complete(packet);
3075                     break;
3076 
3077                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3078                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3079                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3080                     conn = hci_connection_for_handle(handle);
3081                     if (!conn) break;
3082                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3083                     break;
3084 
3085                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3086                     // connection
3087                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3088                     conn = hci_connection_for_handle(handle);
3089                     if (conn) {
3090                         // read arguments
3091                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3092                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3093                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3094                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3095 
3096                         // validate against current connection parameter range
3097                         le_connection_parameter_range_t existing_range;
3098                         gap_get_connection_parameter_range(&existing_range);
3099                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3100                         if (update_parameter){
3101                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3102                             conn->le_conn_interval_min = le_conn_interval_min;
3103                             conn->le_conn_interval_max = le_conn_interval_max;
3104                             conn->le_conn_latency = le_conn_latency;
3105                             conn->le_supervision_timeout = le_supervision_timeout;
3106                         } else {
3107                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3108                         }
3109                     }
3110                     break;
3111 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3112                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3113                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3114                     conn = hci_connection_for_handle(handle);
3115                     if (conn) {
3116                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3117                     }
3118                     break;
3119 #endif
3120                 default:
3121                     break;
3122             }
3123             break;
3124 #endif
3125         case HCI_EVENT_VENDOR_SPECIFIC:
3126             // Vendor specific commands often create vendor specific event instead of num completed packets
3127             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3128             switch (hci_stack->manufacturer){
3129                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3130                     hci_stack->num_cmd_packets = 1;
3131                     break;
3132                 default:
3133                     break;
3134             }
3135             break;
3136         default:
3137             break;
3138     }
3139 
3140     handle_event_for_current_stack_state(packet, size);
3141 
3142     // notify upper stack
3143 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3144 
3145     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3146     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3147 		handle = little_endian_read_16(packet, 3);
3148 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3149 		// discard connection if app did not trigger a reconnect in the event handler
3150 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3151 			hci_shutdown_connection(aConn);
3152 		}
3153     }
3154 
3155 	// execute main loop
3156 	hci_run();
3157 }
3158 
3159 #ifdef ENABLE_CLASSIC
3160 
3161 #ifdef ENABLE_SCO_OVER_HCI
3162 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3163 static void sco_schedule_tx(hci_connection_t * conn);
3164 
3165 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3166     log_debug("SCO TX Timeout");
3167     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3168     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3169     if (!conn) return;
3170 
3171     // trigger send
3172     conn->sco_tx_ready = 1;
3173     // extra packet if CVSD but SCO buffer is too short
3174     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3175         conn->sco_tx_ready++;
3176     }
3177     hci_notify_if_sco_can_send_now();
3178 }
3179 
3180 
3181 #define SCO_TX_AFTER_RX_MS (6)
3182 
3183 static void sco_schedule_tx(hci_connection_t * conn){
3184 
3185     uint32_t now = btstack_run_loop_get_time_ms();
3186     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3187     int time_delta_ms = sco_tx_ms - now;
3188 
3189     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3190 
3191     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3192     btstack_run_loop_remove_timer(timer);
3193     btstack_run_loop_set_timer(timer, time_delta_ms);
3194     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3195     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3196     btstack_run_loop_add_timer(timer);
3197 }
3198 #endif
3199 
3200 static void sco_handler(uint8_t * packet, uint16_t size){
3201     // lookup connection struct
3202     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3203     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3204     if (!conn) return;
3205 
3206 #ifdef ENABLE_SCO_OVER_HCI
3207     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3208     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3209         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3210             packet[2] = 0x3c;
3211             memmove(&packet[3], &packet[23], 63);
3212             size = 63;
3213         }
3214     }
3215 
3216     if (hci_have_usb_transport()){
3217         // Nothing to do
3218     } else {
3219         // 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);
3220         if (hci_stack->synchronous_flow_control_enabled == 0){
3221             uint32_t now = btstack_run_loop_get_time_ms();
3222 
3223             if (!conn->sco_rx_valid){
3224                 // ignore first 10 packets
3225                 conn->sco_rx_count++;
3226                 // log_debug("sco rx count %u", conn->sco_rx_count);
3227                 if (conn->sco_rx_count == 10) {
3228                     // use first timestamp as is and pretent it just started
3229                     conn->sco_rx_ms = now;
3230                     conn->sco_rx_valid = 1;
3231                     conn->sco_rx_count = 0;
3232                     sco_schedule_tx(conn);
3233                 }
3234             } else {
3235                 // track expected arrival timme
3236                 conn->sco_rx_count++;
3237                 conn->sco_rx_ms += 7;
3238                 int delta = (int32_t) (now - conn->sco_rx_ms);
3239                 if (delta > 0){
3240                     conn->sco_rx_ms++;
3241                 }
3242                 // log_debug("sco rx %u", conn->sco_rx_ms);
3243                 sco_schedule_tx(conn);
3244             }
3245         }
3246     }
3247 #endif
3248 
3249     // deliver to app
3250     if (hci_stack->sco_packet_handler) {
3251         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3252     }
3253 
3254 #ifdef HAVE_SCO_TRANSPORT
3255     // We can send one packet for each received packet
3256     conn->sco_tx_ready++;
3257     hci_notify_if_sco_can_send_now();
3258 #endif
3259 
3260 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3261     conn->num_packets_completed++;
3262     hci_stack->host_completed_packets = 1;
3263     hci_run();
3264 #endif
3265 }
3266 #endif
3267 
3268 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3269     hci_dump_packet(packet_type, 1, packet, size);
3270     switch (packet_type) {
3271         case HCI_EVENT_PACKET:
3272             event_handler(packet, size);
3273             break;
3274         case HCI_ACL_DATA_PACKET:
3275             acl_handler(packet, size);
3276             break;
3277 #ifdef ENABLE_CLASSIC
3278         case HCI_SCO_DATA_PACKET:
3279             sco_handler(packet, size);
3280             break;
3281 #endif
3282         default:
3283             break;
3284     }
3285 }
3286 
3287 /**
3288  * @brief Add event packet handler.
3289  */
3290 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3291     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3292 }
3293 
3294 
3295 /** Register HCI packet handlers */
3296 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3297     hci_stack->acl_packet_handler = handler;
3298 }
3299 
3300 #ifdef ENABLE_CLASSIC
3301 /**
3302  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3303  */
3304 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3305     hci_stack->sco_packet_handler = handler;
3306 }
3307 #endif
3308 
3309 static void hci_state_reset(void){
3310     // no connections yet
3311     hci_stack->connections = NULL;
3312 
3313     // keep discoverable/connectable as this has been requested by the client(s)
3314     // hci_stack->discoverable = 0;
3315     // hci_stack->connectable = 0;
3316     // hci_stack->bondable = 1;
3317     // hci_stack->own_addr_type = 0;
3318 
3319     // buffer is free
3320     hci_stack->hci_packet_buffer_reserved = 0;
3321 
3322     // no pending cmds
3323     hci_stack->decline_reason = 0;
3324     hci_stack->new_scan_enable_value = 0xff;
3325 
3326     hci_stack->secure_connections_active = false;
3327 
3328 #ifdef ENABLE_CLASSIC
3329     hci_stack->new_page_scan_interval = 0xffff;
3330     hci_stack->new_page_scan_window = 0xffff;
3331     hci_stack->new_page_scan_type = 0xff;
3332     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3333 #endif
3334 
3335 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3336     hci_stack->classic_read_local_oob_data = true;
3337 #endif
3338 
3339     // LE
3340 #ifdef ENABLE_BLE
3341     memset(hci_stack->le_random_address, 0, 6);
3342     hci_stack->le_random_address_set = 0;
3343 #endif
3344 #ifdef ENABLE_LE_CENTRAL
3345     hci_stack->le_scanning_active  = false;
3346     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3347     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3348     hci_stack->le_whitelist_capacity = 0;
3349 #endif
3350 #ifdef ENABLE_LE_PERIPHERAL
3351     hci_stack->le_advertisements_active = false;
3352     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3353         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3354     }
3355     if (hci_stack->le_advertisements_data != NULL){
3356         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3357     }
3358 #endif
3359 }
3360 
3361 #ifdef ENABLE_CLASSIC
3362 /**
3363  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3364  */
3365 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3366     // store and open remote device db
3367     hci_stack->link_key_db = link_key_db;
3368     if (hci_stack->link_key_db) {
3369         hci_stack->link_key_db->open();
3370     }
3371 }
3372 #endif
3373 
3374 void hci_init(const hci_transport_t *transport, const void *config){
3375 
3376 #ifdef HAVE_MALLOC
3377     if (!hci_stack) {
3378         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3379     }
3380 #else
3381     hci_stack = &hci_stack_static;
3382 #endif
3383     memset(hci_stack, 0, sizeof(hci_stack_t));
3384 
3385     // reference to use transport layer implementation
3386     hci_stack->hci_transport = transport;
3387 
3388     // reference to used config
3389     hci_stack->config = config;
3390 
3391     // setup pointer for outgoing packet buffer
3392     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3393 
3394     // max acl payload size defined in config.h
3395     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3396 
3397     // register packet handlers with transport
3398     transport->register_packet_handler(&packet_handler);
3399 
3400     hci_stack->state = HCI_STATE_OFF;
3401 
3402     // class of device
3403     hci_stack->class_of_device = 0x007a020c; // Smartphone
3404 
3405     // bondable by default
3406     hci_stack->bondable = 1;
3407 
3408 #ifdef ENABLE_CLASSIC
3409     // classic name
3410     hci_stack->local_name = default_classic_name;
3411 
3412     // Master slave policy
3413     hci_stack->master_slave_policy = 1;
3414 
3415     // Allow Role Switch
3416     hci_stack->allow_role_switch = 1;
3417 
3418     // Default / minimum security level = 2
3419     hci_stack->gap_security_level = LEVEL_2;
3420 
3421     // Default Security Mode 4
3422     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3423 
3424     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3425     hci_stack->gap_required_encyrption_key_size = 7;
3426 
3427     // Link Supervision Timeout
3428     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3429 
3430 #endif
3431 
3432     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3433     hci_stack->ssp_enable = 1;
3434     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3435     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3436     hci_stack->ssp_auto_accept = 1;
3437 
3438     // Secure Connections: enable (requires support from Controller)
3439     hci_stack->secure_connections_enable = true;
3440 
3441     // voice setting - signed 16 bit pcm data with CVSD over the air
3442     hci_stack->sco_voice_setting = 0x60;
3443 
3444 #ifdef ENABLE_LE_CENTRAL
3445     // connection parameter to use for outgoing connections
3446     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3447     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3448     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3449     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3450     hci_stack->le_connection_latency      = 4;         // 4
3451     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3452     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3453     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3454 
3455     // default LE Scanning
3456     hci_stack->le_scan_type     =   0x1; // active
3457     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3458     hci_stack->le_scan_window   =  0x30; //  30 ms
3459 #endif
3460 
3461 #ifdef ENABLE_LE_PERIPHERAL
3462     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3463 #endif
3464 
3465     // connection parameter range used to answer connection parameter update requests in l2cap
3466     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3467     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3468     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3469     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3470     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3471     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3472 
3473     hci_state_reset();
3474 }
3475 
3476 void hci_deinit(void){
3477 #ifdef HAVE_MALLOC
3478     if (hci_stack) {
3479         free(hci_stack);
3480     }
3481 #endif
3482     hci_stack = NULL;
3483 
3484 #ifdef ENABLE_CLASSIC
3485     disable_l2cap_timeouts = 0;
3486 #endif
3487 }
3488 
3489 /**
3490  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3491  */
3492 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3493     hci_stack->chipset = chipset_driver;
3494 
3495     // reset chipset driver - init is also called on power_up
3496     if (hci_stack->chipset && hci_stack->chipset->init){
3497         hci_stack->chipset->init(hci_stack->config);
3498     }
3499 }
3500 
3501 /**
3502  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3503  */
3504 void hci_set_control(const btstack_control_t *hardware_control){
3505     // references to used control implementation
3506     hci_stack->control = hardware_control;
3507     // init with transport config
3508     hardware_control->init(hci_stack->config);
3509 }
3510 
3511 void hci_close(void){
3512 
3513 #ifdef ENABLE_CLASSIC
3514     // close remote device db
3515     if (hci_stack->link_key_db) {
3516         hci_stack->link_key_db->close();
3517     }
3518 #endif
3519 
3520     btstack_linked_list_iterator_t lit;
3521     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3522     while (btstack_linked_list_iterator_has_next(&lit)){
3523         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3524         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3525         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3526         hci_shutdown_connection(connection);
3527     }
3528 
3529     hci_power_control(HCI_POWER_OFF);
3530 
3531 #ifdef HAVE_MALLOC
3532     free(hci_stack);
3533 #endif
3534     hci_stack = NULL;
3535 }
3536 
3537 #ifdef HAVE_SCO_TRANSPORT
3538 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3539     hci_stack->sco_transport = sco_transport;
3540     sco_transport->register_packet_handler(&packet_handler);
3541 }
3542 #endif
3543 
3544 #ifdef ENABLE_CLASSIC
3545 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3546     // validate ranage and set
3547     if (encryption_key_size < 7)  return;
3548     if (encryption_key_size > 16) return;
3549     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3550 }
3551 
3552 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3553     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3554         hci_stack->gap_security_mode = security_mode;
3555         return ERROR_CODE_SUCCESS;
3556     } else {
3557         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3558     }
3559 }
3560 
3561 gap_security_mode_t gap_get_security_mode(void){
3562     return hci_stack->gap_security_mode;
3563 }
3564 
3565 void gap_set_security_level(gap_security_level_t security_level){
3566     hci_stack->gap_security_level = security_level;
3567 }
3568 
3569 gap_security_level_t gap_get_security_level(void){
3570     if (hci_stack->gap_secure_connections_only_mode){
3571         return LEVEL_4;
3572     }
3573     return hci_stack->gap_security_level;
3574 }
3575 
3576 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3577     hci_stack->gap_minimal_service_security_level = security_level;
3578 }
3579 
3580 void gap_set_secure_connections_only_mode(bool enable){
3581     hci_stack->gap_secure_connections_only_mode = enable;
3582 }
3583 
3584 bool gap_get_secure_connections_only_mode(void){
3585     return hci_stack->gap_secure_connections_only_mode;
3586 }
3587 #endif
3588 
3589 #ifdef ENABLE_CLASSIC
3590 void gap_set_class_of_device(uint32_t class_of_device){
3591     hci_stack->class_of_device = class_of_device;
3592 }
3593 
3594 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3595     hci_stack->default_link_policy_settings = default_link_policy_settings;
3596 }
3597 
3598 void gap_set_allow_role_switch(bool allow_role_switch){
3599     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3600 }
3601 
3602 uint8_t hci_get_allow_role_switch(void){
3603     return  hci_stack->allow_role_switch;
3604 }
3605 
3606 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3607     hci_stack->link_supervision_timeout = link_supervision_timeout;
3608 }
3609 
3610 void hci_disable_l2cap_timeout_check(void){
3611     disable_l2cap_timeouts = 1;
3612 }
3613 #endif
3614 
3615 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3616 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3617 void hci_set_bd_addr(bd_addr_t addr){
3618     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3619     hci_stack->custom_bd_addr_set = 1;
3620 }
3621 #endif
3622 
3623 // State-Module-Driver overview
3624 // state                    module  low-level
3625 // HCI_STATE_OFF             off      close
3626 // HCI_STATE_INITIALIZING,   on       open
3627 // HCI_STATE_WORKING,        on       open
3628 // HCI_STATE_HALTING,        on       open
3629 // HCI_STATE_SLEEPING,    off/sleep   close
3630 // HCI_STATE_FALLING_ASLEEP  on       open
3631 
3632 static int hci_power_control_on(void){
3633 
3634     // power on
3635     int err = 0;
3636     if (hci_stack->control && hci_stack->control->on){
3637         err = (*hci_stack->control->on)();
3638     }
3639     if (err){
3640         log_error( "POWER_ON failed");
3641         hci_emit_hci_open_failed();
3642         return err;
3643     }
3644 
3645     // int chipset driver
3646     if (hci_stack->chipset && hci_stack->chipset->init){
3647         hci_stack->chipset->init(hci_stack->config);
3648     }
3649 
3650     // init transport
3651     if (hci_stack->hci_transport->init){
3652         hci_stack->hci_transport->init(hci_stack->config);
3653     }
3654 
3655     // open transport
3656     err = hci_stack->hci_transport->open();
3657     if (err){
3658         log_error( "HCI_INIT failed, turning Bluetooth off again");
3659         if (hci_stack->control && hci_stack->control->off){
3660             (*hci_stack->control->off)();
3661         }
3662         hci_emit_hci_open_failed();
3663         return err;
3664     }
3665     return 0;
3666 }
3667 
3668 static void hci_power_control_off(void){
3669 
3670     log_info("hci_power_control_off");
3671 
3672     // close low-level device
3673     hci_stack->hci_transport->close();
3674 
3675     log_info("hci_power_control_off - hci_transport closed");
3676 
3677     // power off
3678     if (hci_stack->control && hci_stack->control->off){
3679         (*hci_stack->control->off)();
3680     }
3681 
3682     log_info("hci_power_control_off - control closed");
3683 
3684     hci_stack->state = HCI_STATE_OFF;
3685 }
3686 
3687 static void hci_power_control_sleep(void){
3688 
3689     log_info("hci_power_control_sleep");
3690 
3691 #if 0
3692     // don't close serial port during sleep
3693 
3694     // close low-level device
3695     hci_stack->hci_transport->close(hci_stack->config);
3696 #endif
3697 
3698     // sleep mode
3699     if (hci_stack->control && hci_stack->control->sleep){
3700         (*hci_stack->control->sleep)();
3701     }
3702 
3703     hci_stack->state = HCI_STATE_SLEEPING;
3704 }
3705 
3706 static int hci_power_control_wake(void){
3707 
3708     log_info("hci_power_control_wake");
3709 
3710     // wake on
3711     if (hci_stack->control && hci_stack->control->wake){
3712         (*hci_stack->control->wake)();
3713     }
3714 
3715 #if 0
3716     // open low-level device
3717     int err = hci_stack->hci_transport->open(hci_stack->config);
3718     if (err){
3719         log_error( "HCI_INIT failed, turning Bluetooth off again");
3720         if (hci_stack->control && hci_stack->control->off){
3721             (*hci_stack->control->off)();
3722         }
3723         hci_emit_hci_open_failed();
3724         return err;
3725     }
3726 #endif
3727 
3728     return 0;
3729 }
3730 
3731 static void hci_power_transition_to_initializing(void){
3732     // set up state machine
3733     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3734     hci_stack->hci_packet_buffer_reserved = 0;
3735     hci_stack->state = HCI_STATE_INITIALIZING;
3736     hci_stack->substate = HCI_INIT_SEND_RESET;
3737 }
3738 
3739 // returns error
3740 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3741     int err;
3742     switch (power_mode){
3743         case HCI_POWER_ON:
3744             err = hci_power_control_on();
3745             if (err != 0) {
3746                 log_error("hci_power_control_on() error %d", err);
3747                 return err;
3748             }
3749             hci_power_transition_to_initializing();
3750             break;
3751         case HCI_POWER_OFF:
3752             // do nothing
3753             break;
3754         case HCI_POWER_SLEEP:
3755             // do nothing (with SLEEP == OFF)
3756             break;
3757         default:
3758             btstack_assert(false);
3759             break;
3760     }
3761     return ERROR_CODE_SUCCESS;
3762 }
3763 
3764 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3765     switch (power_mode){
3766         case HCI_POWER_ON:
3767             // do nothing
3768             break;
3769         case HCI_POWER_OFF:
3770             // no connections yet, just turn it off
3771             hci_power_control_off();
3772             break;
3773         case HCI_POWER_SLEEP:
3774             // no connections yet, just turn it off
3775             hci_power_control_sleep();
3776             break;
3777         default:
3778             btstack_assert(false);
3779             break;
3780     }
3781     return ERROR_CODE_SUCCESS;
3782 }
3783 
3784 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3785     switch (power_mode){
3786         case HCI_POWER_ON:
3787             // do nothing
3788             break;
3789         case HCI_POWER_OFF:
3790             // see hci_run
3791             hci_stack->state = HCI_STATE_HALTING;
3792             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3793             break;
3794         case HCI_POWER_SLEEP:
3795             // see hci_run
3796             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3797             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3798             break;
3799         default:
3800             btstack_assert(false);
3801             break;
3802     }
3803     return ERROR_CODE_SUCCESS;
3804 }
3805 
3806 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3807     switch (power_mode){
3808         case HCI_POWER_ON:
3809             hci_power_transition_to_initializing();
3810             break;
3811         case HCI_POWER_OFF:
3812             // do nothing
3813             break;
3814         case HCI_POWER_SLEEP:
3815             // see hci_run
3816             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3817             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3818             break;
3819         default:
3820             btstack_assert(false);
3821             break;
3822     }
3823     return ERROR_CODE_SUCCESS;
3824 }
3825 
3826 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3827     switch (power_mode){
3828         case HCI_POWER_ON:
3829 
3830 #ifdef HAVE_PLATFORM_IPHONE_OS
3831             // nothing to do, if H4 supports power management
3832                     if (btstack_control_iphone_power_management_enabled()){
3833                         hci_stack->state = HCI_STATE_INITIALIZING;
3834                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3835                         break;
3836                     }
3837 #endif
3838             hci_power_transition_to_initializing();
3839             break;
3840         case HCI_POWER_OFF:
3841             // see hci_run
3842             hci_stack->state = HCI_STATE_HALTING;
3843             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3844             break;
3845         case HCI_POWER_SLEEP:
3846             // do nothing
3847             break;
3848         default:
3849             btstack_assert(false);
3850             break;
3851     }
3852     return ERROR_CODE_SUCCESS;
3853 }
3854 
3855 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3856     int err;
3857     switch (power_mode){
3858         case HCI_POWER_ON:
3859 #ifdef HAVE_PLATFORM_IPHONE_OS
3860             // nothing to do, if H4 supports power management
3861                     if (btstack_control_iphone_power_management_enabled()){
3862                         hci_stack->state = HCI_STATE_INITIALIZING;
3863                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3864                         hci_update_scan_enable();
3865                         break;
3866                     }
3867 #endif
3868             err = hci_power_control_wake();
3869             if (err) return err;
3870             hci_power_transition_to_initializing();
3871             break;
3872         case HCI_POWER_OFF:
3873             hci_stack->state = HCI_STATE_HALTING;
3874             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3875             break;
3876         case HCI_POWER_SLEEP:
3877             // do nothing
3878             break;
3879         default:
3880             btstack_assert(false);
3881             break;
3882     }
3883     return ERROR_CODE_SUCCESS;
3884 }
3885 
3886 int hci_power_control(HCI_POWER_MODE power_mode){
3887     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3888     int err = 0;
3889     switch (hci_stack->state){
3890         case HCI_STATE_OFF:
3891             err = hci_power_control_state_off(power_mode);
3892             break;
3893         case HCI_STATE_INITIALIZING:
3894             err = hci_power_control_state_initializing(power_mode);
3895             break;
3896         case HCI_STATE_WORKING:
3897             err = hci_power_control_state_working(power_mode);
3898             break;
3899         case HCI_STATE_HALTING:
3900             err = hci_power_control_state_halting(power_mode);
3901             break;
3902         case HCI_STATE_FALLING_ASLEEP:
3903             err = hci_power_control_state_falling_asleep(power_mode);
3904             break;
3905         case HCI_STATE_SLEEPING:
3906             err = hci_power_control_state_sleeping(power_mode);
3907             break;
3908         default:
3909             btstack_assert(false);
3910             break;
3911     }
3912     if (err != 0){
3913         return err;
3914     }
3915 
3916     // create internal event
3917 	hci_emit_state();
3918 
3919 	// trigger next/first action
3920 	hci_run();
3921 
3922     return 0;
3923 }
3924 
3925 
3926 #ifdef ENABLE_CLASSIC
3927 
3928 static void hci_update_scan_enable(void){
3929     // 2 = page scan, 1 = inq scan
3930     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3931     hci_run();
3932 }
3933 
3934 void gap_discoverable_control(uint8_t enable){
3935     if (enable) enable = 1; // normalize argument
3936 
3937     if (hci_stack->discoverable == enable){
3938         hci_emit_discoverable_enabled(hci_stack->discoverable);
3939         return;
3940     }
3941 
3942     hci_stack->discoverable = enable;
3943     hci_update_scan_enable();
3944 }
3945 
3946 void gap_connectable_control(uint8_t enable){
3947     if (enable) enable = 1; // normalize argument
3948 
3949     // don't emit event
3950     if (hci_stack->connectable == enable) return;
3951 
3952     hci_stack->connectable = enable;
3953     hci_update_scan_enable();
3954 }
3955 #endif
3956 
3957 void gap_local_bd_addr(bd_addr_t address_buffer){
3958     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3959 }
3960 
3961 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3962 static void hci_host_num_completed_packets(void){
3963 
3964     // create packet manually as arrays are not supported and num_commands should not get reduced
3965     hci_reserve_packet_buffer();
3966     uint8_t * packet = hci_get_outgoing_packet_buffer();
3967 
3968     uint16_t size = 0;
3969     uint16_t num_handles = 0;
3970     packet[size++] = 0x35;
3971     packet[size++] = 0x0c;
3972     size++;  // skip param len
3973     size++;  // skip num handles
3974 
3975     // add { handle, packets } entries
3976     btstack_linked_item_t * it;
3977     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3978         hci_connection_t * connection = (hci_connection_t *) it;
3979         if (connection->num_packets_completed){
3980             little_endian_store_16(packet, size, connection->con_handle);
3981             size += 2;
3982             little_endian_store_16(packet, size, connection->num_packets_completed);
3983             size += 2;
3984             //
3985             num_handles++;
3986             connection->num_packets_completed = 0;
3987         }
3988     }
3989 
3990     packet[2] = size - 3;
3991     packet[3] = num_handles;
3992 
3993     hci_stack->host_completed_packets = 0;
3994 
3995     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3996     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3997 
3998     // release packet buffer for synchronous transport implementations
3999     if (hci_transport_synchronous()){
4000         hci_release_packet_buffer();
4001         hci_emit_transport_packet_sent();
4002     }
4003 }
4004 #endif
4005 
4006 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4007     UNUSED(ds);
4008     hci_stack->substate = HCI_HALTING_CLOSE;
4009     // allow packet handlers to defer final shutdown
4010     hci_emit_state();
4011     hci_run();
4012 }
4013 
4014 static bool hci_run_acl_fragments(void){
4015     if (hci_stack->acl_fragmentation_total_size > 0u) {
4016         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4017         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4018         if (connection) {
4019             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4020                 hci_send_acl_packet_fragments(connection);
4021                 return true;
4022             }
4023         } else {
4024             // connection gone -> discard further fragments
4025             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4026             hci_stack->acl_fragmentation_total_size = 0;
4027             hci_stack->acl_fragmentation_pos = 0;
4028         }
4029     }
4030     return false;
4031 }
4032 
4033 #ifdef ENABLE_CLASSIC
4034 static bool hci_run_general_gap_classic(void){
4035 
4036     // decline incoming connections
4037     if (hci_stack->decline_reason){
4038         uint8_t reason = hci_stack->decline_reason;
4039         hci_stack->decline_reason = 0;
4040         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4041         return true;
4042     }
4043     // write page scan activity
4044     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_interval != 0xffff) && hci_classic_supported()){
4045         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
4046         hci_stack->new_page_scan_interval = 0xffff;
4047         hci_stack->new_page_scan_window = 0xffff;
4048         return true;
4049     }
4050     // write page scan type
4051     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_type != 0xff) && hci_classic_supported()){
4052         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
4053         hci_stack->new_page_scan_type = 0xff;
4054         return true;
4055     }
4056     // send scan enable
4057     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
4058         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
4059         hci_stack->new_scan_enable_value = 0xff;
4060         return true;
4061     }
4062     // start/stop inquiry
4063     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4064         uint8_t duration = hci_stack->inquiry_state;
4065         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4066         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4067         return true;
4068     }
4069     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4070         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4071         hci_send_cmd(&hci_inquiry_cancel);
4072         return true;
4073     }
4074     // remote name request
4075     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4076         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4077         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4078                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4079         return true;
4080     }
4081 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4082     // Local OOB data
4083     if ((hci_stack->state == HCI_STATE_WORKING) && hci_stack->classic_read_local_oob_data){
4084         hci_stack->classic_read_local_oob_data = false;
4085         if (hci_stack->local_supported_commands[1] & 0x10u){
4086             hci_send_cmd(&hci_read_local_extended_oob_data);
4087         } else {
4088             hci_send_cmd(&hci_read_local_oob_data);
4089         }
4090     }
4091 #endif
4092     // pairing
4093     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4094         uint8_t state = hci_stack->gap_pairing_state;
4095         uint8_t pin_code[16];
4096         switch (state){
4097             case GAP_PAIRING_STATE_SEND_PIN:
4098                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4099                 memset(pin_code, 0, 16);
4100                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4101                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4102                 break;
4103             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4104                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4105                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4106                 break;
4107             case GAP_PAIRING_STATE_SEND_PASSKEY:
4108                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4109                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4110                 break;
4111             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4112                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4113                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4114                 break;
4115             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4116                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4117                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4118                 break;
4119             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4120                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4121                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4122                 break;
4123             default:
4124                 break;
4125         }
4126         return true;
4127     }
4128     return false;
4129 }
4130 #endif
4131 
4132 #ifdef ENABLE_BLE
4133 static bool hci_run_general_gap_le(void){
4134 
4135     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4136 
4137     if (hci_stack->state != HCI_STATE_WORKING) return false;
4138     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4139 
4140 
4141     // Phase 1: collect what to stop
4142 
4143     bool scanning_stop = false;
4144     bool connecting_stop = false;
4145     bool advertising_stop = false;
4146 
4147 #ifndef ENABLE_LE_CENTRAL
4148     UNUSED(scanning_stop);
4149     UNUSED(connecting_stop);
4150 #endif
4151 #ifndef ENABLE_LE_PERIPHERAL
4152     UNUSED(advertising_stop);
4153 #endif
4154 
4155     // check if whitelist needs modification
4156     bool whitelist_modification_pending = false;
4157     btstack_linked_list_iterator_t lit;
4158     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4159     while (btstack_linked_list_iterator_has_next(&lit)){
4160         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4161         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4162             whitelist_modification_pending = true;
4163             break;
4164         }
4165     }
4166     // check if resolving list needs modification
4167     bool resolving_list_modification_pending = false;
4168 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4169     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4170 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4171         resolving_list_modification_pending = true;
4172     }
4173 #endif
4174 
4175 #ifdef ENABLE_LE_CENTRAL
4176     // scanning control
4177     if (hci_stack->le_scanning_active) {
4178         // stop if:
4179         // - parameter change required
4180         // - it's disabled
4181         // - whitelist change required but used for scanning
4182         // - resolving list modified
4183         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4184         if ((hci_stack->le_scanning_param_update) ||
4185             !hci_stack->le_scanning_enabled ||
4186             scanning_uses_whitelist ||
4187             resolving_list_modification_pending){
4188 
4189             scanning_stop = true;
4190         }
4191     }
4192 #endif
4193 
4194 #ifdef ENABLE_LE_CENTRAL
4195     // connecting control
4196     bool connecting_with_whitelist;
4197     switch (hci_stack->le_connecting_state){
4198         case LE_CONNECTING_DIRECT:
4199         case LE_CONNECTING_WHITELIST:
4200             // stop connecting if:
4201             // - connecting uses white and whitelist modification pending
4202             // - if it got disabled
4203             // - resolving list modified
4204             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4205             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4206                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4207                 resolving_list_modification_pending) {
4208 
4209                 connecting_stop = true;
4210             }
4211             break;
4212         default:
4213             break;
4214     }
4215 #endif
4216 
4217 #ifdef ENABLE_LE_PERIPHERAL
4218     // le advertisement control
4219     if (hci_stack->le_advertisements_active){
4220         // stop if:
4221         // - parameter change required
4222         // - it's disabled
4223         // - whitelist change required but used for advertisement filter policy
4224         // - resolving list modified
4225         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4226         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4227         if (advertising_change ||
4228             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4229             (advertising_uses_whitelist & whitelist_modification_pending) ||
4230             resolving_list_modification_pending) {
4231 
4232             advertising_stop = true;
4233         }
4234     }
4235 #endif
4236 
4237 
4238     // Phase 2: stop everything that should be off during modifications
4239 
4240 #ifdef ENABLE_LE_CENTRAL
4241     if (scanning_stop){
4242         hci_stack->le_scanning_active = false;
4243         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4244         return true;
4245     }
4246 #endif
4247 
4248 #ifdef ENABLE_LE_CENTRAL
4249     if (connecting_stop){
4250         hci_send_cmd(&hci_le_create_connection_cancel);
4251         return true;
4252     }
4253 #endif
4254 
4255 #ifdef ENABLE_LE_PERIPHERAL
4256     if (advertising_stop){
4257         hci_stack->le_advertisements_active = false;
4258         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4259         return true;
4260     }
4261 #endif
4262 
4263     // Phase 3: modify
4264 
4265 #ifdef ENABLE_LE_CENTRAL
4266     if (hci_stack->le_scanning_param_update){
4267         hci_stack->le_scanning_param_update = false;
4268         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4269                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4270         return true;
4271     }
4272 #endif
4273 
4274 #ifdef ENABLE_LE_PERIPHERAL
4275     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4276         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4277         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4278         hci_send_cmd(&hci_le_set_advertising_parameters,
4279                      hci_stack->le_advertisements_interval_min,
4280                      hci_stack->le_advertisements_interval_max,
4281                      hci_stack->le_advertisements_type,
4282                      hci_stack->le_advertisements_own_addr_type,
4283                      hci_stack->le_advertisements_direct_address_type,
4284                      hci_stack->le_advertisements_direct_address,
4285                      hci_stack->le_advertisements_channel_map,
4286                      hci_stack->le_advertisements_filter_policy);
4287         return true;
4288     }
4289     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4290         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4291         uint8_t adv_data_clean[31];
4292         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4293         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4294                      hci_stack->le_advertisements_data_len);
4295         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4296         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4297         return true;
4298     }
4299     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4300         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4301         uint8_t scan_data_clean[31];
4302         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4303         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4304                      hci_stack->le_scan_response_data_len);
4305         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4306         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4307         return true;
4308     }
4309 #endif
4310 
4311 
4312 #ifdef ENABLE_LE_CENTRAL
4313     // if connect with whitelist was active and is not cancelled yet, wait until next time
4314     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4315 #endif
4316 
4317     // LE Whitelist Management
4318     if (whitelist_modification_pending){
4319         // add/remove entries
4320         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4321         while (btstack_linked_list_iterator_has_next(&lit)){
4322             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4323 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4324 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4325 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4326 				return true;
4327 			}
4328             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4329 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4330                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4331                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4332                 return true;
4333             }
4334             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4335 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4336 				btstack_memory_whitelist_entry_free(entry);
4337             }
4338         }
4339     }
4340 
4341 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4342     // LE Resolving List Management
4343     if (resolving_list_supported) {
4344 		uint16_t i;
4345 		switch (hci_stack->le_resolving_list_state) {
4346 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4347 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4348 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4349 				return true;
4350 			case LE_RESOLVING_LIST_READ_SIZE:
4351 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4352 				hci_send_cmd(&hci_le_read_resolving_list_size);
4353 				return true;
4354 			case LE_RESOLVING_LIST_SEND_CLEAR:
4355 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4356 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4357 							  sizeof(hci_stack->le_resolving_list_add_entries));
4358 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4359 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4360 				hci_send_cmd(&hci_le_clear_resolving_list);
4361 				return true;
4362 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4363 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4364 					uint8_t offset = i >> 3;
4365 					uint8_t mask = 1 << (i & 7);
4366 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4367 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4368 					bd_addr_t peer_identity_addreses;
4369 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4370 					sm_key_t peer_irk;
4371 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4372 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4373 
4374 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4375 					// trigger whitelist entry 'update' (work around for controller bug)
4376 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4377 					while (btstack_linked_list_iterator_has_next(&lit)) {
4378 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4379 						if (entry->address_type != peer_identity_addr_type) continue;
4380 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4381 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4382 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4383 					}
4384 #endif
4385 
4386 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4387 								 peer_identity_addreses);
4388 					return true;
4389 				}
4390 
4391 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4392 
4393 				/* fall through */
4394 
4395 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4396 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4397 					uint8_t offset = i >> 3;
4398 					uint8_t mask = 1 << (i & 7);
4399 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4400 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4401 					bd_addr_t peer_identity_addreses;
4402 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4403 					sm_key_t peer_irk;
4404 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4405 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4406 					const uint8_t *local_irk = gap_get_persistent_irk();
4407 					// command uses format specifier 'P' that stores 16-byte value without flip
4408 					uint8_t local_irk_flipped[16];
4409 					uint8_t peer_irk_flipped[16];
4410 					reverse_128(local_irk, local_irk_flipped);
4411 					reverse_128(peer_irk, peer_irk_flipped);
4412 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4413 								 peer_irk_flipped, local_irk_flipped);
4414 					return true;
4415 				}
4416 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4417 				break;
4418 
4419 			default:
4420 				break;
4421 		}
4422 	}
4423     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4424 #endif
4425 
4426     // Phase 4: restore state
4427 
4428 #ifdef ENABLE_LE_CENTRAL
4429     // re-start scanning
4430     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4431         hci_stack->le_scanning_active = true;
4432         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4433         return true;
4434     }
4435 #endif
4436 
4437 #ifdef ENABLE_LE_CENTRAL
4438     // re-start connecting
4439     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4440         bd_addr_t null_addr;
4441         memset(null_addr, 0, 6);
4442         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4443         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4444         hci_send_cmd(&hci_le_create_connection,
4445                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4446                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4447                      1,         // use whitelist
4448                      0,         // peer address type
4449                      null_addr, // peer bd addr
4450                      hci_stack->le_connection_own_addr_type,   // our addr type:
4451                      hci_stack->le_connection_interval_min,    // conn interval min
4452                      hci_stack->le_connection_interval_max,    // conn interval max
4453                      hci_stack->le_connection_latency,         // conn latency
4454                      hci_stack->le_supervision_timeout,        // conn latency
4455                      hci_stack->le_minimum_ce_length,          // min ce length
4456                      hci_stack->le_maximum_ce_length           // max ce length
4457         );
4458         return true;
4459     }
4460 #endif
4461 
4462 #ifdef ENABLE_LE_PERIPHERAL
4463     // re-start advertising
4464     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4465         // check if advertisements should be enabled given
4466         hci_stack->le_advertisements_active = true;
4467         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_advertisements_own_address);
4468         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4469         return true;
4470     }
4471 #endif
4472 
4473     return false;
4474 }
4475 #endif
4476 
4477 static bool hci_run_general_pending_commands(void){
4478     btstack_linked_item_t * it;
4479     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4480         hci_connection_t * connection = (hci_connection_t *) it;
4481 
4482         switch(connection->state){
4483             case SEND_CREATE_CONNECTION:
4484                 switch(connection->address_type){
4485 #ifdef ENABLE_CLASSIC
4486                     case BD_ADDR_TYPE_ACL:
4487                         log_info("sending hci_create_connection");
4488                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4489                         break;
4490 #endif
4491                     default:
4492 #ifdef ENABLE_BLE
4493 #ifdef ENABLE_LE_CENTRAL
4494                         log_info("sending hci_le_create_connection");
4495                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4496                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4497                         hci_send_cmd(&hci_le_create_connection,
4498                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4499                                      hci_stack->le_connection_scan_window,      // conn scan windows
4500                                      0,         // don't use whitelist
4501                                      connection->address_type, // peer address type
4502                                      connection->address,      // peer bd addr
4503                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4504                                      hci_stack->le_connection_interval_min,    // conn interval min
4505                                      hci_stack->le_connection_interval_max,    // conn interval max
4506                                      hci_stack->le_connection_latency,         // conn latency
4507                                      hci_stack->le_supervision_timeout,        // conn latency
4508                                      hci_stack->le_minimum_ce_length,          // min ce length
4509                                      hci_stack->le_maximum_ce_length          // max ce length
4510                         );
4511                         connection->state = SENT_CREATE_CONNECTION;
4512 #endif
4513 #endif
4514                         break;
4515                 }
4516                 return true;
4517 
4518 #ifdef ENABLE_CLASSIC
4519             case RECEIVED_CONNECTION_REQUEST:
4520                 connection->role  = HCI_ROLE_SLAVE;
4521                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4522                     log_info("sending hci_accept_connection_request");
4523                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4524                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4525                 }
4526                 return true;
4527 #endif
4528 
4529 #ifdef ENABLE_BLE
4530 #ifdef ENABLE_LE_CENTRAL
4531             case SEND_CANCEL_CONNECTION:
4532                 connection->state = SENT_CANCEL_CONNECTION;
4533                 hci_send_cmd(&hci_le_create_connection_cancel);
4534                 return true;
4535 #endif
4536 #endif
4537             case SEND_DISCONNECT:
4538                 connection->state = SENT_DISCONNECT;
4539                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4540                 return true;
4541 
4542             default:
4543                 break;
4544         }
4545 
4546         // no further commands if connection is about to get shut down
4547         if (connection->state == SENT_DISCONNECT) continue;
4548 
4549         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4550             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4551             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4552             return true;
4553         }
4554 
4555 #ifdef ENABLE_CLASSIC
4556 
4557         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4558             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4559             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4560             return true;
4561         }
4562 
4563         // Handling link key request requires remote supported features
4564         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4565             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4566             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4567 
4568             // lookup link key using cached key first
4569             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4570             if (!have_link_key && (hci_stack->link_key_db != NULL)){
4571                 have_link_key = hci_stack->link_key_db->get_link_key(connection->address, connection->link_key, &connection->link_key_type);
4572             }
4573 
4574             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4575             if (have_link_key && security_level_sufficient){
4576                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4577             } else {
4578                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4579             }
4580             return true;
4581         }
4582 
4583         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4584             log_info("denying to pin request");
4585             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4586             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4587             return true;
4588         }
4589 
4590         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4591             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4592             // set authentication requirements:
4593             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4594             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4595             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4596             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4597                 authreq |= 1;
4598             }
4599             bool bonding = hci_stack->bondable;
4600             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4601                 // if we have received IO Cap Response, we're in responder role
4602                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4603                 if (bonding && !remote_bonding){
4604                     log_info("Remote not bonding, dropping local flag");
4605                     bonding = false;
4606                 }
4607             }
4608             if (bonding){
4609                 if (connection->bonding_flags & BONDING_DEDICATED){
4610                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4611                 } else {
4612                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4613                 }
4614             }
4615             uint8_t have_oob_data = 0;
4616 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4617             if (connection->classic_oob_c_192 != NULL){
4618                     have_oob_data |= 1;
4619             }
4620             if (connection->classic_oob_c_256 != NULL){
4621                 have_oob_data |= 2;
4622             }
4623 #endif
4624             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4625             return true;
4626         }
4627 
4628         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4629             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4630             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4631             return true;
4632         }
4633 
4634 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4635         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4636             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4637             const uint8_t zero[16] = { 0 };
4638             const uint8_t * r_192 = zero;
4639             const uint8_t * c_192 = zero;
4640             const uint8_t * r_256 = zero;
4641             const uint8_t * c_256 = zero;
4642             // verify P-256 OOB
4643             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4644                 c_256 = connection->classic_oob_c_256;
4645                 if (connection->classic_oob_r_256 != NULL) {
4646                     r_256 = connection->classic_oob_r_256;
4647                 }
4648             }
4649             // verify P-192 OOB
4650             if ((connection->classic_oob_c_192 != NULL)) {
4651                 c_192 = connection->classic_oob_c_192;
4652                 if (connection->classic_oob_r_192 != NULL) {
4653                     r_192 = connection->classic_oob_r_192;
4654                 }
4655             }
4656 
4657             // assess security
4658             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4659             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4660             if (need_level_4 && !can_reach_level_4){
4661                 log_info("Level 4 required, but not possible -> abort");
4662                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4663                 // send oob negative reply
4664                 c_256 = NULL;
4665                 c_192 = NULL;
4666             }
4667 
4668             // Reply
4669             if (c_256 != zero) {
4670                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4671             } else if (c_192 != zero){
4672                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4673             } else {
4674                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4675             }
4676             return true;
4677         }
4678 #endif
4679 
4680         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4681             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4682             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4683             return true;
4684         }
4685 
4686         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4687             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4688             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4689             return true;
4690         }
4691 
4692         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4693             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4694             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4695             return true;
4696         }
4697 
4698         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4699             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4700             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4701             return true;
4702         }
4703 
4704         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4705             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4706             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4707             return true;
4708         }
4709 
4710         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4711             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4712             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4713             return true;
4714         }
4715 
4716         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4717             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4718             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4719             connection->state = SENT_DISCONNECT;
4720             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4721             return true;
4722         }
4723 
4724         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4725             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4726             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4727             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4728             return true;
4729         }
4730 
4731         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4732             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4733             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4734             return true;
4735         }
4736         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4737             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4738             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4739             return true;
4740         }
4741 #endif
4742 
4743         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4744             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4745 #ifdef ENABLE_CLASSIC
4746             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4747 #endif
4748             if (connection->state != SENT_DISCONNECT){
4749                 connection->state = SENT_DISCONNECT;
4750                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4751                 return true;
4752             }
4753         }
4754 
4755 #ifdef ENABLE_CLASSIC
4756         uint16_t sniff_min_interval;
4757         switch (connection->sniff_min_interval){
4758             case 0:
4759                 break;
4760             case 0xffff:
4761                 connection->sniff_min_interval = 0;
4762                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4763                 return true;
4764             default:
4765                 sniff_min_interval = connection->sniff_min_interval;
4766                 connection->sniff_min_interval = 0;
4767                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4768                 return true;
4769         }
4770 
4771         if (connection->sniff_subrating_max_latency != 0xffff){
4772             uint16_t max_latency = connection->sniff_subrating_max_latency;
4773             connection->sniff_subrating_max_latency = 0;
4774             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4775             return true;
4776         }
4777 
4778         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4779             uint8_t service_type = (uint8_t) connection->qos_service_type;
4780             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4781             hci_send_cmd(&hci_qos_setup, connection->con_handle, 0, service_type, connection->qos_token_rate, connection->qos_peak_bandwidth, connection->qos_latency, connection->qos_delay_variation);
4782             return true;
4783         }
4784 
4785         if (connection->request_role != HCI_ROLE_INVALID){
4786             hci_role_t role = connection->request_role;
4787             connection->request_role = HCI_ROLE_INVALID;
4788             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4789             return true;
4790         }
4791 #endif
4792 
4793 #ifdef ENABLE_BLE
4794         switch (connection->le_con_parameter_update_state){
4795             // response to L2CAP CON PARAMETER UPDATE REQUEST
4796             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4797                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4798                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4799                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4800                              0x0000, 0xffff);
4801                 return true;
4802             case CON_PARAMETER_UPDATE_REPLY:
4803                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4804                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4805                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4806                              0x0000, 0xffff);
4807                 return true;
4808             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4809                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4810                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4811                 return true;
4812             default:
4813                 break;
4814         }
4815         if (connection->le_phy_update_all_phys != 0xffu){
4816             uint8_t all_phys = connection->le_phy_update_all_phys;
4817             connection->le_phy_update_all_phys = 0xff;
4818             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);
4819             return true;
4820         }
4821 #endif
4822     }
4823     return false;
4824 }
4825 
4826 static void hci_run(void){
4827 
4828     bool done;
4829 
4830     // send continuation fragments first, as they block the prepared packet buffer
4831     done = hci_run_acl_fragments();
4832     if (done) return;
4833 
4834 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4835     // send host num completed packets next as they don't require num_cmd_packets > 0
4836     if (!hci_can_send_comand_packet_transport()) return;
4837     if (hci_stack->host_completed_packets){
4838         hci_host_num_completed_packets();
4839         return;
4840     }
4841 #endif
4842 
4843     if (!hci_can_send_command_packet_now()) return;
4844 
4845     // global/non-connection oriented commands
4846 
4847 
4848 #ifdef ENABLE_CLASSIC
4849     // general gap classic
4850     done = hci_run_general_gap_classic();
4851     if (done) return;
4852 #endif
4853 
4854 #ifdef ENABLE_BLE
4855     // general gap le
4856     done = hci_run_general_gap_le();
4857     if (done) return;
4858 #endif
4859 
4860     // send pending HCI commands
4861     done = hci_run_general_pending_commands();
4862     if (done) return;
4863 
4864     // stack state sub statemachines
4865     hci_connection_t * connection;
4866     switch (hci_stack->state){
4867         case HCI_STATE_INITIALIZING:
4868             hci_initializing_run();
4869             break;
4870 
4871         case HCI_STATE_HALTING:
4872 
4873             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4874             switch (hci_stack->substate){
4875                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4876                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4877 
4878 #ifdef ENABLE_BLE
4879 #ifdef ENABLE_LE_CENTRAL
4880                     // free whitelist entries
4881                     {
4882                         btstack_linked_list_iterator_t lit;
4883                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4884                         while (btstack_linked_list_iterator_has_next(&lit)){
4885                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4886                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4887                             btstack_memory_whitelist_entry_free(entry);
4888                         }
4889                     }
4890 #endif
4891 #endif
4892                     // close all open connections
4893                     connection =  (hci_connection_t *) hci_stack->connections;
4894                     if (connection){
4895                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4896                         if (!hci_can_send_command_packet_now()) return;
4897 
4898                         // check state
4899                         if (connection->state == SENT_DISCONNECT) return;
4900                         connection->state = SENT_DISCONNECT;
4901 
4902                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4903 
4904                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4905                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4906 
4907                         // ... which would be ignored anyway as we shutdown (free) the connection now
4908                         hci_shutdown_connection(connection);
4909 
4910                         // finally, send the disconnect command
4911                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4912                         return;
4913                     }
4914 
4915                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4916                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4917                         log_info("HCI_STATE_HALTING: wait 50 ms");
4918                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4919                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4920                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4921                         btstack_run_loop_add_timer(&hci_stack->timeout);
4922                         break;
4923                     }
4924 
4925                     /* fall through */
4926 
4927                 case HCI_HALTING_CLOSE:
4928                     log_info("HCI_STATE_HALTING, calling off");
4929 
4930                     // switch mode
4931                     hci_power_control_off();
4932 
4933                     log_info("HCI_STATE_HALTING, emitting state");
4934                     hci_emit_state();
4935                     log_info("HCI_STATE_HALTING, done");
4936                     break;
4937 
4938                 case HCI_HALTING_W4_TIMER:
4939                     // keep waiting
4940 
4941                     break;
4942                 default:
4943                     break;
4944             }
4945 
4946             break;
4947 
4948         case HCI_STATE_FALLING_ASLEEP:
4949             switch(hci_stack->substate) {
4950                 case HCI_FALLING_ASLEEP_DISCONNECT:
4951                     log_info("HCI_STATE_FALLING_ASLEEP");
4952                     // close all open connections
4953                     connection =  (hci_connection_t *) hci_stack->connections;
4954 
4955 #ifdef HAVE_PLATFORM_IPHONE_OS
4956                     // don't close connections, if H4 supports power management
4957                     if (btstack_control_iphone_power_management_enabled()){
4958                         connection = NULL;
4959                     }
4960 #endif
4961                     if (connection){
4962 
4963                         // send disconnect
4964                         if (!hci_can_send_command_packet_now()) return;
4965 
4966                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4967                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4968 
4969                         // send disconnected event right away - causes higher layer connections to get closed, too.
4970                         hci_shutdown_connection(connection);
4971                         return;
4972                     }
4973 
4974                     if (hci_classic_supported()){
4975                         // disable page and inquiry scan
4976                         if (!hci_can_send_command_packet_now()) return;
4977 
4978                         log_info("HCI_STATE_HALTING, disabling inq scans");
4979                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4980 
4981                         // continue in next sub state
4982                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4983                         break;
4984                     }
4985 
4986                     /* fall through */
4987 
4988                 case HCI_FALLING_ASLEEP_COMPLETE:
4989                     log_info("HCI_STATE_HALTING, calling sleep");
4990 #ifdef HAVE_PLATFORM_IPHONE_OS
4991                     // don't actually go to sleep, if H4 supports power management
4992                     if (btstack_control_iphone_power_management_enabled()){
4993                         // SLEEP MODE reached
4994                         hci_stack->state = HCI_STATE_SLEEPING;
4995                         hci_emit_state();
4996                         break;
4997                     }
4998 #endif
4999                     // switch mode
5000                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5001                     hci_emit_state();
5002                     break;
5003 
5004                 default:
5005                     break;
5006             }
5007             break;
5008 
5009         default:
5010             break;
5011     }
5012 }
5013 
5014 int hci_send_cmd_packet(uint8_t *packet, int size){
5015     // house-keeping
5016 
5017 #ifdef ENABLE_CLASSIC
5018     bd_addr_t addr;
5019     hci_connection_t * conn;
5020 #endif
5021 #ifdef ENABLE_LE_CENTRAL
5022     uint8_t initiator_filter_policy;
5023 #endif
5024 
5025     uint16_t opcode = little_endian_read_16(packet, 0);
5026     switch (opcode) {
5027         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5028             hci_stack->loopback_mode = packet[3];
5029             break;
5030 
5031 #ifdef ENABLE_CLASSIC
5032         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5033             reverse_bd_addr(&packet[3], addr);
5034             log_info("Create_connection to %s", bd_addr_to_str(addr));
5035 
5036             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5037             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5038                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5039                 return -1;
5040             }
5041 
5042             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5043             if (!conn) {
5044                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5045                 if (!conn) {
5046                     // notify client that alloc failed
5047                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5048                     return -1; // packet not sent to controller
5049                 }
5050                 conn->state = SEND_CREATE_CONNECTION;
5051                 conn->role  = HCI_ROLE_MASTER;
5052             }
5053             log_info("conn state %u", conn->state);
5054             switch (conn->state) {
5055                 // if connection active exists
5056                 case OPEN:
5057                     // and OPEN, emit connection complete command
5058                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5059                     return -1; // packet not sent to controller
5060                 case RECEIVED_DISCONNECTION_COMPLETE:
5061                     // create connection triggered in disconnect complete event, let's do it now
5062                     break;
5063                 case SEND_CREATE_CONNECTION:
5064                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5065                     break;
5066                 default:
5067                     // otherwise, just ignore as it is already in the open process
5068                     return -1; // packet not sent to controller
5069             }
5070             conn->state = SENT_CREATE_CONNECTION;
5071 
5072             // track outgoing connection
5073             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5074             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5075             break;
5076         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5077             if (hci_stack->link_key_db) {
5078                 reverse_bd_addr(&packet[3], addr);
5079                 hci_stack->link_key_db->delete_link_key(addr);
5080             }
5081             break;
5082 
5083 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5084         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5085             // setup_synchronous_connection? Voice setting at offset 22
5086             // TODO: compare to current setting if sco connection already active
5087             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5088             break;
5089         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5090             // accept_synchronus_connection? Voice setting at offset 18
5091             // TODO: compare to current setting if sco connection already active
5092             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5093             break;
5094 #endif
5095 #endif
5096 
5097 #ifdef ENABLE_BLE
5098         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5099             hci_stack->le_random_address_set = 1;
5100             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5101             break;
5102 #ifdef ENABLE_LE_PERIPHERAL
5103         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5104             hci_stack->le_advertisements_active = packet[3] != 0;
5105             break;
5106 #endif
5107 #ifdef ENABLE_LE_CENTRAL
5108         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5109             // white list used?
5110             initiator_filter_policy = packet[7];
5111             switch (initiator_filter_policy) {
5112                 case 0:
5113                     // whitelist not used
5114                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5115                     break;
5116                 case 1:
5117                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5118                     break;
5119                 default:
5120                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5121                     break;
5122             }
5123             // track outgoing connection
5124             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5125             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5126             break;
5127         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5128             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5129             break;
5130 #endif
5131 #endif
5132         default:
5133             break;
5134     }
5135 
5136     hci_stack->num_cmd_packets--;
5137 
5138     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5139     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5140 }
5141 
5142 // disconnect because of security block
5143 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5144     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5145     if (!connection) return;
5146     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5147 }
5148 
5149 
5150 // Configure Secure Simple Pairing
5151 
5152 #ifdef ENABLE_CLASSIC
5153 
5154 // enable will enable SSP during init
5155 void gap_ssp_set_enable(int enable){
5156     hci_stack->ssp_enable = enable;
5157 }
5158 
5159 static int hci_local_ssp_activated(void){
5160     return gap_ssp_supported() && hci_stack->ssp_enable;
5161 }
5162 
5163 // if set, BTstack will respond to io capability request using authentication requirement
5164 void gap_ssp_set_io_capability(int io_capability){
5165     hci_stack->ssp_io_capability = io_capability;
5166 }
5167 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5168     hci_stack->ssp_authentication_requirement = authentication_requirement;
5169 }
5170 
5171 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5172 void gap_ssp_set_auto_accept(int auto_accept){
5173     hci_stack->ssp_auto_accept = auto_accept;
5174 }
5175 
5176 void gap_secure_connections_enable(bool enable){
5177     hci_stack->secure_connections_enable = enable;
5178 }
5179 
5180 #endif
5181 
5182 // va_list part of hci_send_cmd
5183 int hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5184     if (!hci_can_send_command_packet_now()){
5185         log_error("hci_send_cmd called but cannot send packet now");
5186         return 0;
5187     }
5188 
5189     // for HCI INITIALIZATION
5190     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5191     hci_stack->last_cmd_opcode = cmd->opcode;
5192 
5193     hci_reserve_packet_buffer();
5194     uint8_t * packet = hci_stack->hci_packet_buffer;
5195     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5196     int err = hci_send_cmd_packet(packet, size);
5197 
5198     // release packet buffer on error or for synchronous transport implementations
5199     if ((err < 0) || hci_transport_synchronous()){
5200         hci_release_packet_buffer();
5201         hci_emit_transport_packet_sent();
5202     }
5203 
5204     return err;
5205 }
5206 
5207 /**
5208  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5209  */
5210 int hci_send_cmd(const hci_cmd_t * cmd, ...){
5211     va_list argptr;
5212     va_start(argptr, cmd);
5213     int res = hci_send_cmd_va_arg(cmd, argptr);
5214     va_end(argptr);
5215     return res;
5216 }
5217 
5218 // Create various non-HCI events.
5219 // TODO: generalize, use table similar to hci_create_command
5220 
5221 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5222     // dump packet
5223     if (dump) {
5224         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5225     }
5226 
5227     // dispatch to all event handlers
5228     btstack_linked_list_iterator_t it;
5229     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5230     while (btstack_linked_list_iterator_has_next(&it)){
5231         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5232         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5233     }
5234 }
5235 
5236 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5237     if (!hci_stack->acl_packet_handler) return;
5238     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5239 }
5240 
5241 #ifdef ENABLE_CLASSIC
5242 static void hci_notify_if_sco_can_send_now(void){
5243     // notify SCO sender if waiting
5244     if (!hci_stack->sco_waiting_for_can_send_now) return;
5245     if (hci_can_send_sco_packet_now()){
5246         hci_stack->sco_waiting_for_can_send_now = 0;
5247         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5248         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5249         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5250     }
5251 }
5252 
5253 // parsing end emitting has been merged to reduce code size
5254 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5255     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5256 
5257     uint8_t * eir_data;
5258     ad_context_t context;
5259     const uint8_t * name;
5260     uint8_t         name_len;
5261 
5262     if (size < 3) return;
5263 
5264     int event_type = hci_event_packet_get_type(packet);
5265     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5266     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5267 
5268     switch (event_type){
5269         case HCI_EVENT_INQUIRY_RESULT:
5270         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5271             if (size != (3 + (num_responses * 14))) return;
5272             break;
5273         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5274             if (size != 257) return;
5275             if (num_responses != 1) return;
5276             break;
5277         default:
5278             return;
5279     }
5280 
5281     // event[1] is set at the end
5282     int i;
5283     for (i=0; i<num_responses;i++){
5284         memset(event, 0, sizeof(event));
5285         event[0] = GAP_EVENT_INQUIRY_RESULT;
5286         uint8_t event_size = 27;    // if name is not set by EIR
5287 
5288         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5289         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5290         (void)memcpy(&event[9],
5291                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5292                      3); // class of device
5293         (void)memcpy(&event[12],
5294                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5295                      2); // clock offset
5296 
5297         switch (event_type){
5298             case HCI_EVENT_INQUIRY_RESULT:
5299                 // 14,15,16,17 = 0, size 18
5300                 break;
5301             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5302                 event[14] = 1;
5303                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5304                 // 16,17 = 0, size 18
5305                 break;
5306             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5307                 event[14] = 1;
5308                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5309                 // EIR packets only contain a single inquiry response
5310                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5311                 name = NULL;
5312                 // Iterate over EIR data
5313                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5314                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5315                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5316                     const uint8_t * data = ad_iterator_get_data(&context);
5317                     // Prefer Complete Local Name over Shortened Local Name
5318                     switch (data_type){
5319                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5320                             if (name) continue;
5321                             /* fall through */
5322                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5323                             name = data;
5324                             name_len = data_size;
5325                             break;
5326                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5327                             if (data_size != 8) break;
5328                             event[16] = 1;
5329                             memcpy(&event[17], data, 8);
5330                             break;
5331                         default:
5332                             break;
5333                     }
5334                 }
5335                 if (name){
5336                     event[25] = 1;
5337                     // truncate name if needed
5338                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5339                     event[26] = len;
5340                     (void)memcpy(&event[27], name, len);
5341                     event_size += len;
5342                 }
5343                 break;
5344             default:
5345                 return;
5346         }
5347         event[1] = event_size - 2;
5348         hci_emit_event(event, event_size, 1);
5349     }
5350 }
5351 #endif
5352 
5353 void hci_emit_state(void){
5354     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5355     uint8_t event[3];
5356     event[0] = BTSTACK_EVENT_STATE;
5357     event[1] = sizeof(event) - 2u;
5358     event[2] = hci_stack->state;
5359     hci_emit_event(event, sizeof(event), 1);
5360 }
5361 
5362 #ifdef ENABLE_CLASSIC
5363 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5364     uint8_t event[13];
5365     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5366     event[1] = sizeof(event) - 2;
5367     event[2] = status;
5368     little_endian_store_16(event, 3, con_handle);
5369     reverse_bd_addr(address, &event[5]);
5370     event[11] = 1; // ACL connection
5371     event[12] = 0; // encryption disabled
5372     hci_emit_event(event, sizeof(event), 1);
5373 }
5374 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5375     if (disable_l2cap_timeouts) return;
5376     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5377     uint8_t event[4];
5378     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5379     event[1] = sizeof(event) - 2;
5380     little_endian_store_16(event, 2, conn->con_handle);
5381     hci_emit_event(event, sizeof(event), 1);
5382 }
5383 #endif
5384 
5385 #ifdef ENABLE_BLE
5386 #ifdef ENABLE_LE_CENTRAL
5387 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){
5388     uint8_t event[21];
5389     event[0] = HCI_EVENT_LE_META;
5390     event[1] = sizeof(event) - 2u;
5391     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5392     event[3] = status;
5393     little_endian_store_16(event, 4, con_handle);
5394     event[6] = 0; // TODO: role
5395     event[7] = address_type;
5396     reverse_bd_addr(address, &event[8]);
5397     little_endian_store_16(event, 14, 0); // interval
5398     little_endian_store_16(event, 16, 0); // latency
5399     little_endian_store_16(event, 18, 0); // supervision timeout
5400     event[20] = 0; // master clock accuracy
5401     hci_emit_event(event, sizeof(event), 1);
5402 }
5403 #endif
5404 #endif
5405 
5406 static void hci_emit_transport_packet_sent(void){
5407     // notify upper stack that it might be possible to send again
5408     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5409     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5410 }
5411 
5412 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5413     uint8_t event[6];
5414     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5415     event[1] = sizeof(event) - 2u;
5416     event[2] = 0; // status = OK
5417     little_endian_store_16(event, 3, con_handle);
5418     event[5] = reason;
5419     hci_emit_event(event, sizeof(event), 1);
5420 }
5421 
5422 static void hci_emit_nr_connections_changed(void){
5423     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5424     uint8_t event[3];
5425     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5426     event[1] = sizeof(event) - 2u;
5427     event[2] = nr_hci_connections();
5428     hci_emit_event(event, sizeof(event), 1);
5429 }
5430 
5431 static void hci_emit_hci_open_failed(void){
5432     log_info("BTSTACK_EVENT_POWERON_FAILED");
5433     uint8_t event[2];
5434     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5435     event[1] = sizeof(event) - 2u;
5436     hci_emit_event(event, sizeof(event), 1);
5437 }
5438 
5439 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5440     log_info("hci_emit_dedicated_bonding_result %u ", status);
5441     uint8_t event[9];
5442     int pos = 0;
5443     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5444     event[pos++] = sizeof(event) - 2u;
5445     event[pos++] = status;
5446     reverse_bd_addr(address, &event[pos]);
5447     hci_emit_event(event, sizeof(event), 1);
5448 }
5449 
5450 
5451 #ifdef ENABLE_CLASSIC
5452 
5453 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5454     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5455     uint8_t event[5];
5456     int pos = 0;
5457     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5458     event[pos++] = sizeof(event) - 2;
5459     little_endian_store_16(event, 2, con_handle);
5460     pos += 2;
5461     event[pos++] = level;
5462     hci_emit_event(event, sizeof(event), 1);
5463 }
5464 
5465 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5466     if (!connection) return LEVEL_0;
5467     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5468     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5469     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5470     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5471     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5472     // LEVEL 4 always requires 128 bit encrytion key size
5473     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5474         security_level = LEVEL_3;
5475     }
5476     return security_level;
5477 }
5478 
5479 static void hci_emit_discoverable_enabled(uint8_t enabled){
5480     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5481     uint8_t event[3];
5482     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5483     event[1] = sizeof(event) - 2;
5484     event[2] = enabled;
5485     hci_emit_event(event, sizeof(event), 1);
5486 }
5487 
5488 // query if remote side supports eSCO
5489 int hci_remote_esco_supported(hci_con_handle_t con_handle){
5490     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5491     if (!connection) return 0;
5492     return (connection->remote_supported_features[0] & 1) != 0;
5493 }
5494 
5495 static bool hci_ssp_supported(hci_connection_t * connection){
5496     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5497     return (connection->bonding_flags & mask) == mask;
5498 }
5499 
5500 // query if remote side supports SSP
5501 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
5502     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5503     if (!connection) return 0;
5504     return hci_ssp_supported(connection) ? 1 : 0;
5505 }
5506 
5507 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5508     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5509 }
5510 
5511 // GAP API
5512 /**
5513  * @bbrief enable/disable bonding. default is enabled
5514  * @praram enabled
5515  */
5516 void gap_set_bondable_mode(int enable){
5517     hci_stack->bondable = enable ? 1 : 0;
5518 }
5519 /**
5520  * @brief Get bondable mode.
5521  * @return 1 if bondable
5522  */
5523 int gap_get_bondable_mode(void){
5524     return hci_stack->bondable;
5525 }
5526 
5527 /**
5528  * @brief map link keys to security levels
5529  */
5530 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5531     switch (link_key_type){
5532         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5533             return LEVEL_4;
5534         case COMBINATION_KEY:
5535         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5536             return LEVEL_3;
5537         default:
5538             return LEVEL_2;
5539     }
5540 }
5541 
5542 /**
5543  * @brief map link keys to secure connection yes/no
5544  */
5545 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5546     switch (link_key_type){
5547         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5548         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5549             return 1;
5550         default:
5551             return 0;
5552     }
5553 }
5554 
5555 /**
5556  * @brief map link keys to authenticated
5557  */
5558 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5559     switch (link_key_type){
5560         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5561         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5562             return 1;
5563         default:
5564             return 0;
5565     }
5566 }
5567 
5568 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5569     log_info("gap_mitm_protection_required_for_security_level %u", level);
5570     return level > LEVEL_2;
5571 }
5572 
5573 /**
5574  * @brief get current security level
5575  */
5576 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5577     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5578     if (!connection) return LEVEL_0;
5579     return gap_security_level_for_connection(connection);
5580 }
5581 
5582 /**
5583  * @brief request connection to device to
5584  * @result GAP_AUTHENTICATION_RESULT
5585  */
5586 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5587     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5588     if (!connection){
5589         hci_emit_security_level(con_handle, LEVEL_0);
5590         return;
5591     }
5592 
5593     btstack_assert(hci_is_le_connection(connection) == false);
5594 
5595     // Core Spec 5.2, GAP 5.2.2: "When in Secure Connections Only mode, all services (except those allowed to have Security Mode 4, Level 0)
5596     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5597     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5598         requested_level = LEVEL_4;
5599     }
5600 
5601     gap_security_level_t current_level = gap_security_level(con_handle);
5602     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5603         requested_level, connection->requested_security_level, current_level);
5604 
5605     // authentication active if authentication request was sent or planned level > 0
5606     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5607     if (authentication_active){
5608         // authentication already active
5609         if (connection->requested_security_level < requested_level){
5610             // increase requested level as new level is higher
5611             // TODO: handle re-authentication when done
5612             connection->requested_security_level = requested_level;
5613         }
5614     } else {
5615         // no request active, notify if security sufficient
5616         if (requested_level <= current_level){
5617             hci_emit_security_level(con_handle, current_level);
5618             return;
5619         }
5620 
5621         // store request
5622         connection->requested_security_level = requested_level;
5623 
5624         // start to authenticate connection
5625         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5626         hci_run();
5627     }
5628 }
5629 
5630 /**
5631  * @brief start dedicated bonding with device. disconnect after bonding
5632  * @param device
5633  * @param request MITM protection
5634  * @result GAP_DEDICATED_BONDING_COMPLETE
5635  */
5636 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5637 
5638     // create connection state machine
5639     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5640 
5641     if (!connection){
5642         return BTSTACK_MEMORY_ALLOC_FAILED;
5643     }
5644 
5645     // delete linkn key
5646     gap_drop_link_key_for_bd_addr(device);
5647 
5648     // configure LEVEL_2/3, dedicated bonding
5649     connection->state = SEND_CREATE_CONNECTION;
5650     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5651     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5652     connection->bonding_flags = BONDING_DEDICATED;
5653 
5654     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5655 
5656     // handle: connnection failure (connection complete != ok)
5657     // handle: authentication failure
5658     // handle: disconnect on done
5659 
5660     hci_run();
5661 
5662     return 0;
5663 }
5664 #endif
5665 
5666 void gap_set_local_name(const char * local_name){
5667     hci_stack->local_name = local_name;
5668 }
5669 
5670 
5671 #ifdef ENABLE_BLE
5672 
5673 #ifdef ENABLE_LE_CENTRAL
5674 void gap_start_scan(void){
5675     hci_stack->le_scanning_enabled = true;
5676     hci_run();
5677 }
5678 
5679 void gap_stop_scan(void){
5680     hci_stack->le_scanning_enabled = false;
5681     hci_run();
5682 }
5683 
5684 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5685     hci_stack->le_scan_type          = scan_type;
5686     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5687     hci_stack->le_scan_interval      = scan_interval;
5688     hci_stack->le_scan_window        = scan_window;
5689     hci_stack->le_scanning_param_update = true;
5690     hci_run();
5691 }
5692 
5693 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5694     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5695 }
5696 
5697 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5698     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5699     if (!conn){
5700         // disallow if le connection is already outgoing
5701         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5702             log_error("le connection already active");
5703             return ERROR_CODE_COMMAND_DISALLOWED;
5704         }
5705 
5706         log_info("gap_connect: no connection exists yet, creating context");
5707         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5708         if (!conn){
5709             // notify client that alloc failed
5710             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5711             log_info("gap_connect: failed to alloc hci_connection_t");
5712             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5713         }
5714 
5715         // set le connecting state
5716         if (hci_is_le_connection_type(addr_type)){
5717             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5718         }
5719 
5720         conn->state = SEND_CREATE_CONNECTION;
5721         log_info("gap_connect: send create connection next");
5722         hci_run();
5723         return ERROR_CODE_SUCCESS;
5724     }
5725 
5726     if (!hci_is_le_connection(conn) ||
5727         (conn->state == SEND_CREATE_CONNECTION) ||
5728         (conn->state == SENT_CREATE_CONNECTION)) {
5729         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5730         log_error("gap_connect: classic connection or connect is already being created");
5731         return GATT_CLIENT_IN_WRONG_STATE;
5732     }
5733 
5734     // check if connection was just disconnected
5735     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5736         log_info("gap_connect: send create connection (again)");
5737         conn->state = SEND_CREATE_CONNECTION;
5738         hci_run();
5739         return ERROR_CODE_SUCCESS;
5740     }
5741 
5742     log_info("gap_connect: context exists with state %u", conn->state);
5743     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5744     hci_run();
5745     return ERROR_CODE_SUCCESS;
5746 }
5747 
5748 // @assumption: only a single outgoing LE Connection exists
5749 static hci_connection_t * gap_get_outgoing_connection(void){
5750     btstack_linked_item_t *it;
5751     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5752         hci_connection_t * conn = (hci_connection_t *) it;
5753         if (!hci_is_le_connection(conn)) continue;
5754         switch (conn->state){
5755             case SEND_CREATE_CONNECTION:
5756             case SENT_CREATE_CONNECTION:
5757             case SENT_CANCEL_CONNECTION:
5758                 return conn;
5759             default:
5760                 break;
5761         };
5762     }
5763     return NULL;
5764 }
5765 
5766 uint8_t gap_connect_cancel(void){
5767     hci_connection_t * conn = gap_get_outgoing_connection();
5768     if (!conn) return 0;
5769     switch (conn->state){
5770         case SEND_CREATE_CONNECTION:
5771             // skip sending create connection and emit event instead
5772             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5773             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5774             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5775             btstack_memory_hci_connection_free( conn );
5776             break;
5777         case SENT_CREATE_CONNECTION:
5778             // request to send cancel connection
5779             conn->state = SEND_CANCEL_CONNECTION;
5780             hci_run();
5781             break;
5782         default:
5783             break;
5784     }
5785     return 0;
5786 }
5787 #endif
5788 
5789 #ifdef ENABLE_LE_CENTRAL
5790 /**
5791  * @brief Set connection parameters for outgoing connections
5792  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5793  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5794  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5795  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5796  * @param conn_latency, default: 4
5797  * @param supervision_timeout (unit: 10ms), default: 720 ms
5798  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5799  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5800  */
5801 
5802 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5803     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5804     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5805     hci_stack->le_connection_scan_interval = conn_scan_interval;
5806     hci_stack->le_connection_scan_window = conn_scan_window;
5807     hci_stack->le_connection_interval_min = conn_interval_min;
5808     hci_stack->le_connection_interval_max = conn_interval_max;
5809     hci_stack->le_connection_latency = conn_latency;
5810     hci_stack->le_supervision_timeout = supervision_timeout;
5811     hci_stack->le_minimum_ce_length = min_ce_length;
5812     hci_stack->le_maximum_ce_length = max_ce_length;
5813 }
5814 #endif
5815 
5816 /**
5817  * @brief Updates the connection parameters for a given LE connection
5818  * @param handle
5819  * @param conn_interval_min (unit: 1.25ms)
5820  * @param conn_interval_max (unit: 1.25ms)
5821  * @param conn_latency
5822  * @param supervision_timeout (unit: 10ms)
5823  * @returns 0 if ok
5824  */
5825 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5826     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5827     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5828     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5829     connection->le_conn_interval_min = conn_interval_min;
5830     connection->le_conn_interval_max = conn_interval_max;
5831     connection->le_conn_latency = conn_latency;
5832     connection->le_supervision_timeout = supervision_timeout;
5833     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5834     hci_run();
5835     return 0;
5836 }
5837 
5838 /**
5839  * @brief Request an update of the connection parameter for a given LE connection
5840  * @param handle
5841  * @param conn_interval_min (unit: 1.25ms)
5842  * @param conn_interval_max (unit: 1.25ms)
5843  * @param conn_latency
5844  * @param supervision_timeout (unit: 10ms)
5845  * @returns 0 if ok
5846  */
5847 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5848     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5849     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5850     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5851     connection->le_conn_interval_min = conn_interval_min;
5852     connection->le_conn_interval_max = conn_interval_max;
5853     connection->le_conn_latency = conn_latency;
5854     connection->le_supervision_timeout = supervision_timeout;
5855     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5856     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5857     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5858     return 0;
5859 }
5860 
5861 #ifdef ENABLE_LE_PERIPHERAL
5862 
5863 /**
5864  * @brief Set Advertisement Data
5865  * @param advertising_data_length
5866  * @param advertising_data (max 31 octets)
5867  * @note data is not copied, pointer has to stay valid
5868  */
5869 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5870     hci_stack->le_advertisements_data_len = advertising_data_length;
5871     hci_stack->le_advertisements_data = advertising_data;
5872     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5873     hci_run();
5874 }
5875 
5876 /**
5877  * @brief Set Scan Response Data
5878  * @param advertising_data_length
5879  * @param advertising_data (max 31 octets)
5880  * @note data is not copied, pointer has to stay valid
5881  */
5882 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5883     hci_stack->le_scan_response_data_len = scan_response_data_length;
5884     hci_stack->le_scan_response_data = scan_response_data;
5885     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5886     hci_run();
5887 }
5888 
5889 /**
5890  * @brief Set Advertisement Parameters
5891  * @param adv_int_min
5892  * @param adv_int_max
5893  * @param adv_type
5894  * @param direct_address_type
5895  * @param direct_address
5896  * @param channel_map
5897  * @param filter_policy
5898  *
5899  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5900  */
5901  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5902     uint8_t direct_address_typ, bd_addr_t direct_address,
5903     uint8_t channel_map, uint8_t filter_policy) {
5904 
5905     hci_stack->le_advertisements_interval_min = adv_int_min;
5906     hci_stack->le_advertisements_interval_max = adv_int_max;
5907     hci_stack->le_advertisements_type = adv_type;
5908     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5909     hci_stack->le_advertisements_channel_map = channel_map;
5910     hci_stack->le_advertisements_filter_policy = filter_policy;
5911     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5912                  6);
5913 
5914     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
5915     hci_run();
5916  }
5917 
5918 /**
5919  * @brief Enable/Disable Advertisements
5920  * @param enabled
5921  */
5922 void gap_advertisements_enable(int enabled){
5923     hci_stack->le_advertisements_enabled = enabled != 0;
5924     hci_update_advertisements_enabled_for_current_roles();
5925     hci_run();
5926 }
5927 
5928 #endif
5929 
5930 void hci_le_set_own_address_type(uint8_t own_address_type){
5931     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5932     if (own_address_type == hci_stack->le_own_addr_type) return;
5933     hci_stack->le_own_addr_type = own_address_type;
5934 
5935 #ifdef ENABLE_LE_PERIPHERAL
5936     // update advertisement parameters, too
5937     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5938     hci_run();
5939 #endif
5940 #ifdef ENABLE_LE_CENTRAL
5941     // note: we don't update scan parameters or modify ongoing connection attempts
5942 #endif
5943 }
5944 
5945 #endif
5946 
5947 uint8_t gap_disconnect(hci_con_handle_t handle){
5948     hci_connection_t * conn = hci_connection_for_handle(handle);
5949     if (!conn){
5950         hci_emit_disconnection_complete(handle, 0);
5951         return 0;
5952     }
5953     // ignore if already disconnected
5954     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5955         return 0;
5956     }
5957     conn->state = SEND_DISCONNECT;
5958     hci_run();
5959     return 0;
5960 }
5961 
5962 int gap_read_rssi(hci_con_handle_t con_handle){
5963     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5964     if (hci_connection == NULL) return 0;
5965     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
5966     hci_run();
5967     return 1;
5968 }
5969 
5970 /**
5971  * @brief Get connection type
5972  * @param con_handle
5973  * @result connection_type
5974  */
5975 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5976     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5977     if (!conn) return GAP_CONNECTION_INVALID;
5978     switch (conn->address_type){
5979         case BD_ADDR_TYPE_LE_PUBLIC:
5980         case BD_ADDR_TYPE_LE_RANDOM:
5981             return GAP_CONNECTION_LE;
5982         case BD_ADDR_TYPE_SCO:
5983             return GAP_CONNECTION_SCO;
5984         case BD_ADDR_TYPE_ACL:
5985             return GAP_CONNECTION_ACL;
5986         default:
5987             return GAP_CONNECTION_INVALID;
5988     }
5989 }
5990 
5991 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5992     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5993     if (!conn) return HCI_ROLE_INVALID;
5994     return (hci_role_t) conn->role;
5995 }
5996 
5997 
5998 #ifdef ENABLE_CLASSIC
5999 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6000     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6001     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6002     conn->request_role = role;
6003     hci_run();
6004     return ERROR_CODE_SUCCESS;
6005 }
6006 #endif
6007 
6008 #ifdef ENABLE_BLE
6009 
6010 uint8_t gap_le_set_phy(hci_con_handle_t con_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
6011     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6012     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6013 
6014     conn->le_phy_update_all_phys    = all_phys;
6015     conn->le_phy_update_tx_phys     = tx_phys;
6016     conn->le_phy_update_rx_phys     = rx_phys;
6017     conn->le_phy_update_phy_options = phy_options;
6018 
6019     hci_run();
6020 
6021     return 0;
6022 }
6023 
6024 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6025     // check if already in list
6026     btstack_linked_list_iterator_t it;
6027     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6028     while (btstack_linked_list_iterator_has_next(&it)) {
6029         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6030         if (entry->address_type != address_type) {
6031             continue;
6032         }
6033         if (memcmp(entry->address, address, 6) != 0) {
6034             continue;
6035         }
6036 		// disallow if already scheduled to add
6037 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6038 			return ERROR_CODE_COMMAND_DISALLOWED;
6039 		}
6040 		// still on controller, but scheduled to remove -> re-add
6041 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6042 		return ERROR_CODE_SUCCESS;
6043     }
6044     // alloc and add to list
6045     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6046     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6047     entry->address_type = address_type;
6048     (void)memcpy(entry->address, address, 6);
6049     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6050     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6051     return ERROR_CODE_SUCCESS;
6052 }
6053 
6054 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6055     btstack_linked_list_iterator_t it;
6056     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6057     while (btstack_linked_list_iterator_has_next(&it)){
6058         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6059         if (entry->address_type != address_type) {
6060             continue;
6061         }
6062         if (memcmp(entry->address, address, 6) != 0) {
6063             continue;
6064         }
6065         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6066             // remove from controller if already present
6067             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6068         }  else {
6069             // directly remove entry from whitelist
6070             btstack_linked_list_iterator_remove(&it);
6071             btstack_memory_whitelist_entry_free(entry);
6072         }
6073         return ERROR_CODE_SUCCESS;
6074     }
6075     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6076 }
6077 
6078 static void hci_whitelist_clear(void){
6079     btstack_linked_list_iterator_t it;
6080     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6081     while (btstack_linked_list_iterator_has_next(&it)){
6082         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6083         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6084             // remove from controller if already present
6085             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6086             continue;
6087         }
6088         // directly remove entry from whitelist
6089         btstack_linked_list_iterator_remove(&it);
6090         btstack_memory_whitelist_entry_free(entry);
6091     }
6092 }
6093 
6094 /**
6095  * @brief Clear Whitelist
6096  * @returns 0 if ok
6097  */
6098 uint8_t gap_whitelist_clear(void){
6099     hci_whitelist_clear();
6100     hci_run();
6101     return ERROR_CODE_SUCCESS;
6102 }
6103 
6104 /**
6105  * @brief Add Device to Whitelist
6106  * @param address_typ
6107  * @param address
6108  * @returns 0 if ok
6109  */
6110 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6111     uint8_t status = hci_whitelist_add(address_type, address);
6112     if (status){
6113         return status;
6114     }
6115     hci_run();
6116     return ERROR_CODE_SUCCESS;
6117 }
6118 
6119 /**
6120  * @brief Remove Device from Whitelist
6121  * @param address_typ
6122  * @param address
6123  * @returns 0 if ok
6124  */
6125 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6126     uint8_t status = hci_whitelist_remove(address_type, address);
6127     if (status){
6128         return status;
6129     }
6130     hci_run();
6131     return ERROR_CODE_SUCCESS;
6132 }
6133 
6134 #ifdef ENABLE_LE_CENTRAL
6135 /**
6136  *  @brief Connect with Whitelist
6137  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6138  *  @returns - if ok
6139  */
6140 uint8_t gap_connect_with_whitelist(void){
6141     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6142         return ERROR_CODE_COMMAND_DISALLOWED;
6143     }
6144     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6145     hci_run();
6146     return ERROR_CODE_SUCCESS;
6147 }
6148 
6149 /**
6150  * @brief Auto Connection Establishment - Start Connecting to device
6151  * @param address_typ
6152  * @param address
6153  * @returns 0 if ok
6154  */
6155 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6156     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6157         return ERROR_CODE_COMMAND_DISALLOWED;
6158     }
6159 
6160     uint8_t status = hci_whitelist_add(address_type, address);
6161     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6162         return status;
6163     }
6164 
6165     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6166 
6167     hci_run();
6168     return ERROR_CODE_SUCCESS;
6169 }
6170 
6171 /**
6172  * @brief Auto Connection Establishment - Stop Connecting to device
6173  * @param address_typ
6174  * @param address
6175  * @returns 0 if ok
6176  */
6177 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6178     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6179         return ERROR_CODE_COMMAND_DISALLOWED;
6180     }
6181 
6182     hci_whitelist_remove(address_type, address);
6183     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6184         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6185     }
6186     hci_run();
6187     return 0;
6188 }
6189 
6190 /**
6191  * @brief Auto Connection Establishment - Stop everything
6192  * @note  Convenience function to stop all active auto connection attempts
6193  */
6194 uint8_t gap_auto_connection_stop_all(void){
6195     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6196         return ERROR_CODE_COMMAND_DISALLOWED;
6197     }
6198     hci_whitelist_clear();
6199     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6200     hci_run();
6201     return ERROR_CODE_SUCCESS;
6202 }
6203 
6204 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6205     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6206     if (!conn) return 0;
6207     return conn->le_connection_interval;
6208 }
6209 #endif
6210 #endif
6211 
6212 #ifdef ENABLE_CLASSIC
6213 /**
6214  * @brief Set Extended Inquiry Response data
6215  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6216  * @note has to be done before stack starts up
6217  */
6218 void gap_set_extended_inquiry_response(const uint8_t * data){
6219     hci_stack->eir_data = data;
6220 }
6221 
6222 /**
6223  * @brief Start GAP Classic Inquiry
6224  * @param duration in 1.28s units
6225  * @return 0 if ok
6226  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6227  */
6228 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6229     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6230     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6231     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6232         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6233     }
6234     hci_stack->inquiry_state = duration_in_1280ms_units;
6235     hci_run();
6236     return 0;
6237 }
6238 
6239 /**
6240  * @brief Stop GAP Classic Inquiry
6241  * @returns 0 if ok
6242  */
6243 int gap_inquiry_stop(void){
6244     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6245         // emit inquiry complete event, before it even started
6246         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6247         hci_emit_event(event, sizeof(event), 1);
6248         return 0;
6249     }
6250     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6251     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6252     hci_run();
6253     return 0;
6254 }
6255 
6256 void gap_inquiry_set_lap(uint32_t lap){
6257     hci_stack->inquiry_lap = lap;
6258 }
6259 
6260 
6261 /**
6262  * @brief Remote Name Request
6263  * @param addr
6264  * @param page_scan_repetition_mode
6265  * @param clock_offset only used when bit 15 is set
6266  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6267  */
6268 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6269     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6270     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6271     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6272     hci_stack->remote_name_clock_offset = clock_offset;
6273     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6274     hci_run();
6275     return 0;
6276 }
6277 
6278 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6279     hci_stack->gap_pairing_state = state;
6280     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6281     hci_run();
6282     return 0;
6283 }
6284 
6285 /**
6286  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6287  * @param addr
6288  * @param pin_data
6289  * @param pin_len
6290  * @return 0 if ok
6291  */
6292 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6293     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6294     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6295     hci_stack->gap_pairing_pin_len = pin_len;
6296     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6297 }
6298 
6299 /**
6300  * @brief Legacy Pairing Pin Code Response
6301  * @param addr
6302  * @param pin
6303  * @return 0 if ok
6304  */
6305 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6306     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6307 }
6308 
6309 /**
6310  * @brief Abort Legacy Pairing
6311  * @param addr
6312  * @param pin
6313  * @return 0 if ok
6314  */
6315 int gap_pin_code_negative(bd_addr_t addr){
6316     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6317     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6318 }
6319 
6320 /**
6321  * @brief SSP Passkey Response
6322  * @param addr
6323  * @param passkey
6324  * @return 0 if ok
6325  */
6326 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6327     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6328     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6329     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6330 }
6331 
6332 /**
6333  * @brief Abort SSP Passkey Entry/Pairing
6334  * @param addr
6335  * @param pin
6336  * @return 0 if ok
6337  */
6338 int gap_ssp_passkey_negative(const bd_addr_t addr){
6339     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6340     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6341 }
6342 
6343 /**
6344  * @brief Accept SSP Numeric Comparison
6345  * @param addr
6346  * @param passkey
6347  * @return 0 if ok
6348  */
6349 int gap_ssp_confirmation_response(const bd_addr_t addr){
6350     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6351     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6352 }
6353 
6354 /**
6355  * @brief Abort SSP Numeric Comparison/Pairing
6356  * @param addr
6357  * @param pin
6358  * @return 0 if ok
6359  */
6360 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6361     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6362     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6363 }
6364 
6365 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6366 
6367 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6368     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6369     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6370     connectionSetAuthenticationFlags(conn, flag);
6371     hci_run();
6372     return ERROR_CODE_SUCCESS;
6373 }
6374 
6375 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6376     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6377 }
6378 
6379 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6380     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6381 }
6382 #endif
6383 
6384 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6385 /**
6386  * @brief Report Remote OOB Data
6387  * @param bd_addr
6388  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6389  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6390  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6391  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6392  */
6393 uint8_t gap_ssp_remote_oob_data(const bd_addr_t addr, const uint8_t * c_192, const uint8_t * r_192, const uint8_t * c_256, const uint8_t * r_256){
6394     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6395     if (connection == NULL) {
6396         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6397     }
6398     connection->classic_oob_c_192 = c_192;
6399     connection->classic_oob_r_192 = r_192;
6400     connection->classic_oob_c_256 = c_256;
6401     connection->classic_oob_r_256 = r_256;
6402     return ERROR_CODE_SUCCESS;
6403 }
6404 /**
6405  * @brief Generate new OOB data
6406  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6407  */
6408 void gap_ssp_generate_oob_data(void){
6409     hci_stack->classic_read_local_oob_data = true;
6410     hci_run();
6411 }
6412 
6413 #endif
6414 
6415 /**
6416  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6417  * @param inquiry_mode see bluetooth_defines.h
6418  */
6419 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6420     hci_stack->inquiry_mode = inquiry_mode;
6421 }
6422 
6423 /**
6424  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6425  */
6426 void hci_set_sco_voice_setting(uint16_t voice_setting){
6427     hci_stack->sco_voice_setting = voice_setting;
6428 }
6429 
6430 /**
6431  * @brief Get SCO Voice Setting
6432  * @return current voice setting
6433  */
6434 uint16_t hci_get_sco_voice_setting(void){
6435     return hci_stack->sco_voice_setting;
6436 }
6437 
6438 static int hci_have_usb_transport(void){
6439     if (!hci_stack->hci_transport) return 0;
6440     const char * transport_name = hci_stack->hci_transport->name;
6441     if (!transport_name) return 0;
6442     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6443 }
6444 
6445 /** @brief Get SCO packet length for current SCO Voice setting
6446  *  @note  Using SCO packets of the exact length is required for USB transfer
6447  *  @return Length of SCO packets in bytes (not audio frames)
6448  */
6449 int hci_get_sco_packet_length(void){
6450     int sco_packet_length = 0;
6451 
6452 #ifdef ENABLE_SCO_OVER_HCI
6453     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6454     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6455 
6456     if (hci_have_usb_transport()){
6457         // see Core Spec for H2 USB Transfer.
6458         // 3 byte SCO header + 24 bytes per connection
6459         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6460         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6461     } else {
6462         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6463         sco_packet_length = 3 + 60 * multiplier;
6464         // assert that it still fits inside an SCO buffer
6465         if (sco_packet_length > hci_stack->sco_data_packet_length){
6466             sco_packet_length = 3 + 60;
6467         }
6468     }
6469 #endif
6470 
6471 #ifdef HAVE_SCO_TRANSPORT
6472     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6473     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6474     sco_packet_length = 3 + 60 * multiplier;
6475 #endif
6476     return sco_packet_length;
6477 }
6478 
6479 /**
6480 * @brief Sets the master/slave policy
6481 * @param policy (0: attempt to become master, 1: let connecting device decide)
6482 */
6483 void hci_set_master_slave_policy(uint8_t policy){
6484     hci_stack->master_slave_policy = policy;
6485 }
6486 
6487 #endif
6488 
6489 HCI_STATE hci_get_state(void){
6490     return hci_stack->state;
6491 }
6492 
6493 #ifdef ENABLE_CLASSIC
6494 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6495     hci_stack->gap_classic_accept_callback = accept_callback;
6496 }
6497 #endif
6498 
6499 /**
6500  * @brief Set callback for Bluetooth Hardware Error
6501  */
6502 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6503     hci_stack->hardware_error_callback = fn;
6504 }
6505 
6506 void hci_disconnect_all(void){
6507     btstack_linked_list_iterator_t it;
6508     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6509     while (btstack_linked_list_iterator_has_next(&it)){
6510         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6511         if (con->state == SENT_DISCONNECT) continue;
6512         con->state = SEND_DISCONNECT;
6513     }
6514     hci_run();
6515 }
6516 
6517 uint16_t hci_get_manufacturer(void){
6518     return hci_stack->manufacturer;
6519 }
6520 
6521 #ifdef ENABLE_BLE
6522 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6523     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6524     if (!hci_con) return NULL;
6525     return &hci_con->sm_connection;
6526 }
6527 
6528 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6529 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6530 #endif
6531 
6532 int gap_encryption_key_size(hci_con_handle_t con_handle){
6533     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6534     if (hci_connection == NULL) return 0;
6535     if (hci_is_le_connection(hci_connection)){
6536 #ifdef ENABLE_BLE
6537         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6538         if (sm_conn->sm_connection_encrypted) {
6539             return sm_conn->sm_actual_encryption_key_size;
6540         }
6541 #endif
6542     } else {
6543 #ifdef ENABLE_CLASSIC
6544         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6545             return hci_connection->encryption_key_size;
6546         }
6547 #endif
6548     }
6549     return 0;
6550 }
6551 
6552 int gap_authenticated(hci_con_handle_t con_handle){
6553     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6554     if (hci_connection == NULL) return 0;
6555 
6556     switch (hci_connection->address_type){
6557 #ifdef ENABLE_BLE
6558         case BD_ADDR_TYPE_LE_PUBLIC:
6559         case BD_ADDR_TYPE_LE_RANDOM:
6560             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6561             return hci_connection->sm_connection.sm_connection_authenticated;
6562 #endif
6563 #ifdef ENABLE_CLASSIC
6564         case BD_ADDR_TYPE_SCO:
6565         case BD_ADDR_TYPE_ACL:
6566             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6567 #endif
6568         default:
6569             return 0;
6570     }
6571 }
6572 
6573 int gap_secure_connection(hci_con_handle_t con_handle){
6574     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6575     if (hci_connection == NULL) return 0;
6576 
6577     switch (hci_connection->address_type){
6578 #ifdef ENABLE_BLE
6579         case BD_ADDR_TYPE_LE_PUBLIC:
6580         case BD_ADDR_TYPE_LE_RANDOM:
6581             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6582             return hci_connection->sm_connection.sm_connection_sc;
6583 #endif
6584 #ifdef ENABLE_CLASSIC
6585         case BD_ADDR_TYPE_SCO:
6586         case BD_ADDR_TYPE_ACL:
6587             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6588 #endif
6589         default:
6590             return 0;
6591     }
6592 }
6593 
6594 bool gap_bonded(hci_con_handle_t con_handle){
6595 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6596 	if (hci_connection == NULL) return 0;
6597 
6598 #ifdef ENABLE_CLASSIC
6599 	link_key_t link_key;
6600 	link_key_type_t link_key_type;
6601 #endif
6602 	switch (hci_connection->address_type){
6603 #ifdef ENABLE_BLE
6604 		case BD_ADDR_TYPE_LE_PUBLIC:
6605 		case BD_ADDR_TYPE_LE_RANDOM:
6606 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6607 #endif
6608 #ifdef ENABLE_CLASSIC
6609 		case BD_ADDR_TYPE_SCO:
6610 		case BD_ADDR_TYPE_ACL:
6611 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6612 #endif
6613 		default:
6614 			return false;
6615 	}
6616 }
6617 
6618 #ifdef ENABLE_BLE
6619 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6620     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6621     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6622     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6623     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6624     return sm_conn->sm_connection_authorization_state;
6625 }
6626 #endif
6627 
6628 #ifdef ENABLE_CLASSIC
6629 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){
6630     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6631     if (!conn) return GAP_CONNECTION_INVALID;
6632     conn->sniff_min_interval = sniff_min_interval;
6633     conn->sniff_max_interval = sniff_max_interval;
6634     conn->sniff_attempt = sniff_attempt;
6635     conn->sniff_timeout = sniff_timeout;
6636     hci_run();
6637     return 0;
6638 }
6639 
6640 /**
6641  * @brief Exit Sniff mode
6642  * @param con_handle
6643  @ @return 0 if ok
6644  */
6645 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6646     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6647     if (!conn) return GAP_CONNECTION_INVALID;
6648     conn->sniff_min_interval = 0xffff;
6649     hci_run();
6650     return 0;
6651 }
6652 
6653 uint8_t gap_sniff_subrating_configure(hci_con_handle_t con_handle, uint16_t max_latency, uint16_t min_remote_timeout, uint16_t min_local_timeout){
6654     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6655     if (!conn) return GAP_CONNECTION_INVALID;
6656     conn->sniff_subrating_max_latency = max_latency;
6657     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6658     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6659     hci_run();
6660     return ERROR_CODE_SUCCESS;
6661 }
6662 
6663 uint8_t gap_qos_set(hci_con_handle_t con_handle, hci_service_type_t service_type, uint32_t token_rate, uint32_t peak_bandwidth, uint32_t latency, uint32_t delay_variation){
6664     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6665     if (!conn) return GAP_CONNECTION_INVALID;
6666     conn->qos_service_type = service_type;
6667     conn->qos_token_rate = token_rate;
6668     conn->qos_peak_bandwidth = peak_bandwidth;
6669     conn->qos_latency = latency;
6670     conn->qos_delay_variation = delay_variation;
6671     hci_run();
6672     return ERROR_CODE_SUCCESS;
6673 }
6674 
6675 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6676     hci_stack->new_page_scan_interval = page_scan_interval;
6677     hci_stack->new_page_scan_window = page_scan_window;
6678     hci_run();
6679 }
6680 
6681 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6682     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6683     hci_run();
6684 }
6685 
6686 #endif
6687 
6688 void hci_halting_defer(void){
6689     if (hci_stack->state != HCI_STATE_HALTING) return;
6690     switch (hci_stack->substate){
6691         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6692         case HCI_HALTING_CLOSE:
6693             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6694             break;
6695         default:
6696             break;
6697     }
6698 }
6699 
6700 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6701 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6702     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6703     if (le_device_db_index >= le_device_db_max_count()) return;
6704     uint8_t offset = le_device_db_index >> 3;
6705     uint8_t mask = 1 << (le_device_db_index & 7);
6706     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6707     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6708     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6709         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6710     }
6711 }
6712 
6713 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6714 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6715 	if (le_device_db_index >= le_device_db_max_count()) return;
6716 	uint8_t offset = le_device_db_index >> 3;
6717 	uint8_t mask = 1 << (le_device_db_index & 7);
6718 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6719 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6720 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6721 	}
6722 }
6723 
6724 uint8_t gap_load_resolving_list_from_le_device_db(void){
6725 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6726 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6727 	}
6728 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6729 		// restart le resolving list update
6730 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6731 	}
6732 	return ERROR_CODE_SUCCESS;
6733 }
6734 #endif
6735 
6736 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6737 void hci_setup_test_connections_fuzz(void){
6738     hci_connection_t * conn;
6739 
6740     // default address: 66:55:44:33:00:01
6741     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6742 
6743     // setup Controller info
6744     hci_stack->num_cmd_packets = 255;
6745     hci_stack->acl_packets_total_num = 255;
6746 
6747     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6748     addr[5] = 0x01;
6749     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6750     conn->con_handle = addr[5];
6751     conn->role  = HCI_ROLE_SLAVE;
6752     conn->state = RECEIVED_CONNECTION_REQUEST;
6753     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6754 
6755     // setup incoming Classic SCO connection with con handle 0x0002
6756     addr[5] = 0x02;
6757     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6758     conn->con_handle = addr[5];
6759     conn->role  = HCI_ROLE_SLAVE;
6760     conn->state = RECEIVED_CONNECTION_REQUEST;
6761     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6762 
6763     // setup ready Classic ACL connection with con handle 0x0003
6764     addr[5] = 0x03;
6765     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6766     conn->con_handle = addr[5];
6767     conn->role  = HCI_ROLE_SLAVE;
6768     conn->state = OPEN;
6769     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6770 
6771     // setup ready Classic SCO connection with con handle 0x0004
6772     addr[5] = 0x04;
6773     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6774     conn->con_handle = addr[5];
6775     conn->role  = HCI_ROLE_SLAVE;
6776     conn->state = OPEN;
6777     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6778 
6779     // setup ready LE ACL connection with con handle 0x005 and public address
6780     addr[5] = 0x05;
6781     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6782     conn->con_handle = addr[5];
6783     conn->role  = HCI_ROLE_SLAVE;
6784     conn->state = OPEN;
6785     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6786     conn->sm_connection.sm_connection_encrypted = 1;
6787 }
6788 
6789 void hci_free_connections_fuzz(void){
6790     btstack_linked_list_iterator_t it;
6791     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6792     while (btstack_linked_list_iterator_has_next(&it)){
6793         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6794         btstack_linked_list_iterator_remove(&it);
6795         btstack_memory_hci_connection_free(con);
6796     }
6797 }
6798 void hci_simulate_working_fuzz(void){
6799     hci_init_done();
6800     hci_stack->num_cmd_packets = 255;
6801 }
6802 #endif
6803