xref: /btstack/src/hci.c (revision c97af5065baa1109a3d77cd7253aa3b61d5604e3)
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 ENABLE_BLE
57 #include "gap.h"
58 #include "ble/le_device_db.h"
59 #endif
60 
61 #include <stdarg.h>
62 #include <string.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "bluetooth_company_id.h"
70 #include "bluetooth_data_types.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 #include "ad_parser.h"
76 
77 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
78 #ifndef HCI_HOST_ACL_PACKET_NUM
79 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
80 #endif
81 #ifndef HCI_HOST_ACL_PACKET_LEN
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
83 #endif
84 #ifndef HCI_HOST_SCO_PACKET_NUM
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_LEN
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
89 #endif
90 #endif
91 
92 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
93 #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."
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
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 HAVE_SCO_TRANSPORT."
98 #endif
99 
100 #define HCI_CONNECTION_TIMEOUT_MS 10000
101 
102 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
103 #define HCI_RESET_RESEND_TIMEOUT_MS 200
104 #endif
105 
106 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
107 #ifndef GAP_INQUIRY_MAX_NAME_LEN
108 #define GAP_INQUIRY_MAX_NAME_LEN 32
109 #endif
110 
111 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
112 #define GAP_INQUIRY_DURATION_MIN       0x01
113 #define GAP_INQUIRY_DURATION_MAX       0x30
114 #define GAP_INQUIRY_STATE_IDLE         0x00
115 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
116 #define GAP_INQUIRY_STATE_ACTIVE       0x81
117 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
118 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
119 
120 // GAP Remote Name Request
121 #define GAP_REMOTE_NAME_STATE_IDLE 0
122 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
123 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
124 
125 // GAP Pairing
126 #define GAP_PAIRING_STATE_IDLE                       0
127 #define GAP_PAIRING_STATE_SEND_PIN                   1
128 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
129 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
130 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
131 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
132 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
133 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
134 
135 // prototypes
136 #ifdef ENABLE_CLASSIC
137 static void hci_update_scan_enable(void);
138 static void hci_emit_discoverable_enabled(uint8_t enabled);
139 static int  hci_local_ssp_activated(void);
140 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
141 static bool hci_ssp_supported(hci_connection_t * connection);
142 static void hci_notify_if_sco_can_send_now(void);
143 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
144 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
145 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
146 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
147 static void hci_connection_timestamp(hci_connection_t *connection);
148 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
149 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
150 #endif
151 
152 static int  hci_power_control_on(void);
153 static void hci_power_control_off(void);
154 static void hci_state_reset(void);
155 static void hci_emit_transport_packet_sent(void);
156 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
157 static void hci_emit_nr_connections_changed(void);
158 static void hci_emit_hci_open_failed(void);
159 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
160 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
161 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
162 static void hci_run(void);
163 static int  hci_is_le_connection(hci_connection_t * connection);
164 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 #endif
169 
170 #ifdef ENABLE_BLE
171 #ifdef ENABLE_LE_CENTRAL
172 // called from test/ble_client/advertising_data_parser.c
173 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
174 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
175 static hci_connection_t * gap_get_outgoing_connection(void);
176 #endif
177 #endif
178 
179 // the STACK is here
180 #ifndef HAVE_MALLOC
181 static hci_stack_t   hci_stack_static;
182 #endif
183 static hci_stack_t * hci_stack = NULL;
184 
185 #ifdef ENABLE_CLASSIC
186 // default name
187 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
188 
189 // test helper
190 static uint8_t disable_l2cap_timeouts = 0;
191 #endif
192 
193 // reset connection state on create and on reconnect
194 // don't overwrite addr, con handle, role
195 static void hci_connection_init(hci_connection_t * conn){
196     conn->authentication_flags = AUTH_FLAG_NONE;
197     conn->bonding_flags = 0;
198     conn->requested_security_level = LEVEL_0;
199 #ifdef ENABLE_CLASSIC
200     conn->request_role = HCI_ROLE_INVALID;
201     conn->sniff_subrating_max_latency = 0xffff;
202     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
203     conn->link_key_type = INVALID_LINK_KEY;
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219 #ifdef ENABLE_CLASSIC_PAIRING_OOB
220     conn->classic_oob_c_192 = NULL;
221     conn->classic_oob_r_192 = NULL;
222     conn->classic_oob_c_256 = NULL;
223     conn->classic_oob_r_256 = NULL;
224 #endif
225 }
226 
227 /**
228  * create connection for given address
229  *
230  * @return connection OR NULL, if no memory left
231  */
232 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
233     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
234 
235     hci_connection_t * conn = btstack_memory_hci_connection_get();
236     if (!conn) return NULL;
237     hci_connection_init(conn);
238 
239     bd_addr_copy(conn->address, addr);
240     conn->address_type = addr_type;
241     conn->con_handle = HCI_CON_HANDLE_INVALID;
242     conn->role = HCI_ROLE_INVALID;
243 
244     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
245 
246     return conn;
247 }
248 
249 
250 /**
251  * get le connection parameter range
252 *
253  * @return le connection parameter range struct
254  */
255 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
256     *range = hci_stack->le_connection_parameter_range;
257 }
258 
259 /**
260  * set le connection parameter range
261  *
262  */
263 
264 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
265     hci_stack->le_connection_parameter_range = *range;
266 }
267 
268 /**
269  * @brief Test if connection parameters are inside in existing rage
270  * @param conn_interval_min (unit: 1.25ms)
271  * @param conn_interval_max (unit: 1.25ms)
272  * @param conn_latency
273  * @param supervision_timeout (unit: 10ms)
274  * @returns 1 if included
275  */
276 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){
277     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
278     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
279 
280     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
281     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
282 
283     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
284     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
285 
286     return 1;
287 }
288 
289 /**
290  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
291  * @note: default: 1
292  * @param max_peripheral_connections
293  */
294 #ifdef ENABLE_LE_PERIPHERAL
295 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
296     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
297 }
298 #endif
299 
300 /**
301  * get hci connections iterator
302  *
303  * @return hci connections iterator
304  */
305 
306 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
307     btstack_linked_list_iterator_init(it, &hci_stack->connections);
308 }
309 
310 /**
311  * get connection for a given handle
312  *
313  * @return connection OR NULL, if not found
314  */
315 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
316     btstack_linked_list_iterator_t it;
317     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
318     while (btstack_linked_list_iterator_has_next(&it)){
319         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
320         if ( item->con_handle == con_handle ) {
321             return item;
322         }
323     }
324     return NULL;
325 }
326 
327 /**
328  * get connection for given address
329  *
330  * @return connection OR NULL, if not found
331  */
332 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != addr_type)  continue;
338         if (memcmp(addr, connection->address, 6) != 0) continue;
339         return connection;
340     }
341     return NULL;
342 }
343 
344 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
345     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
346 }
347 
348 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
349     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
350 }
351 
352 #ifdef ENABLE_CLASSIC
353 
354 #ifdef ENABLE_SCO_OVER_HCI
355 static int hci_number_sco_connections(void){
356     int connections = 0;
357     btstack_linked_list_iterator_t it;
358     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
359     while (btstack_linked_list_iterator_has_next(&it)){
360         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
361         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
362         connections++;
363     }
364     return connections;
365 }
366 #endif
367 
368 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
369     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
370 #ifdef HAVE_EMBEDDED_TICK
371     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
372         // connections might be timed out
373         hci_emit_l2cap_check_timeout(connection);
374     }
375 #else
376     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
377         // connections might be timed out
378         hci_emit_l2cap_check_timeout(connection);
379     }
380 #endif
381 }
382 
383 static void hci_connection_timestamp(hci_connection_t *connection){
384 #ifdef HAVE_EMBEDDED_TICK
385     connection->timestamp = btstack_run_loop_embedded_get_ticks();
386 #else
387     connection->timestamp = btstack_run_loop_get_time_ms();
388 #endif
389 }
390 
391 /**
392  * add authentication flags and reset timer
393  * @note: assumes classic connection
394  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
395  */
396 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
397     bd_addr_t addr;
398     reverse_bd_addr(bd_addr, addr);
399     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
400     if (conn) {
401         connectionSetAuthenticationFlags(conn, flags);
402         hci_connection_timestamp(conn);
403     }
404 }
405 
406 static bool hci_pairing_active(hci_connection_t * hci_connection){
407     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
408 }
409 
410 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
411     if (hci_pairing_active(hci_connection)) return;
412     if (ssp){
413         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
414     } else {
415         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
416     }
417     // if we are initiator, we have sent an HCI Authenticate Request
418     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
419 
420     // if we are responder, use minimal service security level as required level
421     if (!initiator){
422         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);
423     }
424 
425     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
426 
427     uint8_t event[12];
428     event[0] = GAP_EVENT_PAIRING_STARTED;
429     event[1] = 10;
430     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
431     reverse_bd_addr(hci_connection->address, &event[4]);
432     event[10] = (uint8_t) ssp;
433     event[11] = (uint8_t) initiator;
434     hci_emit_event(event, sizeof(event), 1);
435 }
436 
437 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
438     hci_connection->requested_security_level = LEVEL_0;
439     if (!hci_pairing_active(hci_connection)) return;
440     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
441 #ifdef ENABLE_CLASSIC_PAIRING_OOB
442     hci_connection->classic_oob_c_192 = NULL;
443     hci_connection->classic_oob_r_192 = NULL;
444     hci_connection->classic_oob_c_256 = NULL;
445     hci_connection->classic_oob_r_256 = NULL;
446 #endif
447     log_info("pairing complete, status %02x", status);
448 
449     uint8_t event[12];
450     event[0] = GAP_EVENT_PAIRING_COMPLETE;
451     event[1] = 9;
452     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
453     reverse_bd_addr(hci_connection->address, &event[4]);
454     event[10] = status;
455     hci_emit_event(event, sizeof(event), 1);
456 }
457 
458 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
459     hci_connection_t * conn = hci_connection_for_handle(handle);
460     if (!conn) return false;
461     return hci_pairing_active(conn);
462 }
463 
464 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
465     if (!hci_stack->link_key_db) return;
466     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
467     hci_stack->link_key_db->delete_link_key(addr);
468 }
469 
470 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
471     if (!hci_stack->link_key_db) return;
472     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
473     hci_stack->link_key_db->put_link_key(addr, link_key, type);
474 }
475 
476 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
477 	if (!hci_stack->link_key_db) return false;
478 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
479 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
480 	return result;
481 }
482 
483 void gap_delete_all_link_keys(void){
484     bd_addr_t  addr;
485     link_key_t link_key;
486     link_key_type_t type;
487     btstack_link_key_iterator_t it;
488     int ok = gap_link_key_iterator_init(&it);
489     if (!ok) {
490         log_error("could not initialize iterator");
491         return;
492     }
493     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
494         gap_drop_link_key_for_bd_addr(addr);
495     }
496     gap_link_key_iterator_done(&it);
497 }
498 
499 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
500     if (!hci_stack->link_key_db) return 0;
501     if (!hci_stack->link_key_db->iterator_init) return 0;
502     return hci_stack->link_key_db->iterator_init(it);
503 }
504 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){
505     if (!hci_stack->link_key_db) return 0;
506     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
507 }
508 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
509     if (!hci_stack->link_key_db) return;
510     hci_stack->link_key_db->iterator_done(it);
511 }
512 #endif
513 
514 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
515     switch (address_type){
516         case BD_ADDR_TYPE_LE_PUBLIC:
517         case BD_ADDR_TYPE_LE_RANDOM:
518         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
519         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
520             return true;
521         default:
522             return false;
523     }
524 }
525 
526 static int hci_is_le_connection(hci_connection_t * connection){
527     return hci_is_le_connection_type(connection->address_type);
528 }
529 
530 /**
531  * count connections
532  */
533 static int nr_hci_connections(void){
534     int count = 0;
535     btstack_linked_item_t *it;
536     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
537         count++;
538     }
539     return count;
540 }
541 
542 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
543 
544     unsigned int num_packets_sent_classic = 0;
545     unsigned int num_packets_sent_le = 0;
546 
547     btstack_linked_item_t *it;
548     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
549         hci_connection_t * connection = (hci_connection_t *) it;
550         if (hci_is_le_connection(connection)){
551             num_packets_sent_le += connection->num_packets_sent;
552         }
553         if (connection->address_type == BD_ADDR_TYPE_ACL){
554             num_packets_sent_classic += connection->num_packets_sent;
555         }
556     }
557     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
558     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
559     int free_slots_le = 0;
560 
561     if (free_slots_classic < 0){
562         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);
563         return 0;
564     }
565 
566     if (hci_stack->le_acl_packets_total_num){
567         // if we have LE slots, they are used
568         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
569         if (free_slots_le < 0){
570             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);
571             return 0;
572         }
573     } else {
574         // otherwise, classic slots are used for LE, too
575         free_slots_classic -= num_packets_sent_le;
576         if (free_slots_classic < 0){
577             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);
578             return 0;
579         }
580     }
581 
582     switch (address_type){
583         case BD_ADDR_TYPE_UNKNOWN:
584             log_error("hci_number_free_acl_slots: unknown address type");
585             return 0;
586 
587         case BD_ADDR_TYPE_ACL:
588             return free_slots_classic;
589 
590         default:
591            if (hci_stack->le_acl_packets_total_num){
592                return free_slots_le;
593            }
594            return free_slots_classic;
595     }
596 }
597 
598 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
599     // get connection type
600     hci_connection_t * connection = hci_connection_for_handle(con_handle);
601     if (!connection){
602         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
603         return 0;
604     }
605     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
606 }
607 
608 #ifdef ENABLE_CLASSIC
609 static int hci_number_free_sco_slots(void){
610     unsigned int num_sco_packets_sent  = 0;
611     btstack_linked_item_t *it;
612     if (hci_stack->synchronous_flow_control_enabled){
613         // explicit flow control
614         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
615             hci_connection_t * connection = (hci_connection_t *) it;
616             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
617             num_sco_packets_sent += connection->num_packets_sent;
618         }
619         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
620             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
621             return 0;
622         }
623         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
624     } else {
625         // implicit flow control -- TODO
626         int num_ready = 0;
627         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
628             hci_connection_t * connection = (hci_connection_t *) it;
629             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
630             if (connection->sco_tx_ready == 0) continue;
631             num_ready++;
632         }
633         return num_ready;
634     }
635 }
636 #endif
637 
638 // only used to send HCI Host Number Completed Packets
639 static int hci_can_send_comand_packet_transport(void){
640     if (hci_stack->hci_packet_buffer_reserved) return 0;
641 
642     // check for async hci transport implementations
643     if (hci_stack->hci_transport->can_send_packet_now){
644         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
645             return 0;
646         }
647     }
648     return 1;
649 }
650 
651 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
652 bool hci_can_send_command_packet_now(void){
653     if (hci_can_send_comand_packet_transport() == 0) return false;
654     return hci_stack->num_cmd_packets > 0u;
655 }
656 
657 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
658     // check for async hci transport implementations
659     if (!hci_stack->hci_transport->can_send_packet_now) return true;
660     return hci_stack->hci_transport->can_send_packet_now(packet_type);
661 }
662 
663 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
664     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
665     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
666 }
667 
668 bool hci_can_send_acl_le_packet_now(void){
669     if (hci_stack->hci_packet_buffer_reserved) return false;
670     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
671 }
672 
673 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
674     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
675     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
676 }
677 
678 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
679     if (hci_stack->hci_packet_buffer_reserved) return false;
680     return hci_can_send_prepared_acl_packet_now(con_handle);
681 }
682 
683 #ifdef ENABLE_CLASSIC
684 bool hci_can_send_acl_classic_packet_now(void){
685     if (hci_stack->hci_packet_buffer_reserved) return false;
686     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
687 }
688 
689 bool hci_can_send_prepared_sco_packet_now(void){
690     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
691     if (hci_have_usb_transport()){
692         return hci_stack->sco_can_send_now;
693     } else {
694         return hci_number_free_sco_slots() > 0;
695     }
696 }
697 
698 bool hci_can_send_sco_packet_now(void){
699     if (hci_stack->hci_packet_buffer_reserved) return false;
700     return hci_can_send_prepared_sco_packet_now();
701 }
702 
703 void hci_request_sco_can_send_now_event(void){
704     hci_stack->sco_waiting_for_can_send_now = 1;
705     hci_notify_if_sco_can_send_now();
706 }
707 #endif
708 
709 // used for internal checks in l2cap.c
710 bool hci_is_packet_buffer_reserved(void){
711     return hci_stack->hci_packet_buffer_reserved;
712 }
713 
714 // reserves outgoing packet buffer. @returns 1 if successful
715 bool hci_reserve_packet_buffer(void){
716     if (hci_stack->hci_packet_buffer_reserved) {
717         log_error("hci_reserve_packet_buffer called but buffer already reserved");
718         return false;
719     }
720     hci_stack->hci_packet_buffer_reserved = true;
721     return true;
722 }
723 
724 void hci_release_packet_buffer(void){
725     hci_stack->hci_packet_buffer_reserved = false;
726 }
727 
728 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
729 static int hci_transport_synchronous(void){
730     return hci_stack->hci_transport->can_send_packet_now == NULL;
731 }
732 
733 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
734 
735     // 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);
736 
737     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
738     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
739     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
740         max_acl_data_packet_length = hci_stack->le_data_packets_length;
741     }
742 
743 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
744     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
745         max_acl_data_packet_length = connection->le_max_tx_octets;
746     }
747 #endif
748 
749     log_debug("hci_send_acl_packet_fragments entered");
750 
751     uint8_t status = ERROR_CODE_SUCCESS;
752     // multiple packets could be send on a synchronous HCI transport
753     while (true){
754 
755         log_debug("hci_send_acl_packet_fragments loop entered");
756 
757         // get current data
758         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
759         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
760         bool more_fragments = false;
761 
762         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
763         if (current_acl_data_packet_length > max_acl_data_packet_length){
764             more_fragments = true;
765             current_acl_data_packet_length = max_acl_data_packet_length;
766         }
767 
768         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
769         if (acl_header_pos > 0u){
770             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
771             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
772             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
773         }
774 
775         // update header len
776         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
777 
778         // count packet
779         connection->num_packets_sent++;
780         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
781 
782         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
783         if (more_fragments){
784             // update start of next fragment to send
785             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
786         } else {
787             // done
788             hci_stack->acl_fragmentation_pos = 0;
789             hci_stack->acl_fragmentation_total_size = 0;
790         }
791 
792         // send packet
793         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
794         const int size = current_acl_data_packet_length + 4;
795         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
796         hci_stack->acl_fragmentation_tx_active = 1;
797         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
798         if (err != 0){
799             // no error from HCI Transport expected
800             status = ERROR_CODE_HARDWARE_FAILURE;
801         }
802 
803         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
804 
805         // done yet?
806         if (!more_fragments) break;
807 
808         // can send more?
809         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
810     }
811 
812     log_debug("hci_send_acl_packet_fragments loop over");
813 
814     // release buffer now for synchronous transport
815     if (hci_transport_synchronous()){
816         hci_stack->acl_fragmentation_tx_active = 0;
817         hci_release_packet_buffer();
818         hci_emit_transport_packet_sent();
819     }
820 
821     return status;
822 }
823 
824 // pre: caller has reserved the packet buffer
825 uint8_t hci_send_acl_packet_buffer(int size){
826     btstack_assert(hci_stack->hci_packet_buffer_reserved);
827 
828     uint8_t * packet = hci_stack->hci_packet_buffer;
829     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
830 
831     // check for free places on Bluetooth module
832     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
833         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
834         hci_release_packet_buffer();
835         hci_emit_transport_packet_sent();
836         return BTSTACK_ACL_BUFFERS_FULL;
837     }
838 
839     hci_connection_t *connection = hci_connection_for_handle( con_handle);
840     if (!connection) {
841         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
842         hci_release_packet_buffer();
843         hci_emit_transport_packet_sent();
844         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
845     }
846 
847 #ifdef ENABLE_CLASSIC
848     hci_connection_timestamp(connection);
849 #endif
850 
851     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
852 
853     // setup data
854     hci_stack->acl_fragmentation_total_size = size;
855     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
856 
857     return hci_send_acl_packet_fragments(connection);
858 }
859 
860 #ifdef ENABLE_CLASSIC
861 // pre: caller has reserved the packet buffer
862 uint8_t hci_send_sco_packet_buffer(int size){
863     btstack_assert(hci_stack->hci_packet_buffer_reserved);
864 
865     uint8_t * packet = hci_stack->hci_packet_buffer;
866 
867     // skip checks in loopback mode
868     if (!hci_stack->loopback_mode){
869         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
870 
871         // check for free places on Bluetooth module
872         if (!hci_can_send_prepared_sco_packet_now()) {
873             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
874             hci_release_packet_buffer();
875             hci_emit_transport_packet_sent();
876             return BTSTACK_ACL_BUFFERS_FULL;
877         }
878 
879         // track send packet in connection struct
880         hci_connection_t *connection = hci_connection_for_handle( con_handle);
881         if (!connection) {
882             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
883             hci_release_packet_buffer();
884             hci_emit_transport_packet_sent();
885             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
886         }
887 
888         if (hci_have_usb_transport()){
889             // token used
890             hci_stack->sco_can_send_now = false;
891         } else {
892             if (hci_stack->synchronous_flow_control_enabled){
893                 connection->num_packets_sent++;
894             } else {
895                 connection->sco_tx_ready--;
896             }
897         }
898     }
899 
900     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
901 
902 #ifdef HAVE_SCO_TRANSPORT
903     hci_stack->sco_transport->send_packet(packet, size);
904     hci_release_packet_buffer();
905     hci_emit_transport_packet_sent();
906 
907     return 0;
908 #else
909     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
910     if (hci_transport_synchronous()){
911         hci_release_packet_buffer();
912         hci_emit_transport_packet_sent();
913     }
914 
915     if (err != 0){
916         return ERROR_CODE_HARDWARE_FAILURE;
917     }
918     return ERROR_CODE_SUCCESS;
919 #endif
920 }
921 #endif
922 
923 static void acl_handler(uint8_t *packet, uint16_t size){
924 
925     // get info
926     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
927     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
928     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
929     uint16_t acl_length         = READ_ACL_LENGTH(packet);
930 
931     // ignore non-registered handle
932     if (!conn){
933         log_error("acl_handler called with non-registered handle %u!" , con_handle);
934         return;
935     }
936 
937     // assert packet is complete
938     if ((acl_length + 4u) != size){
939         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
940         return;
941     }
942 
943 #ifdef ENABLE_CLASSIC
944     // update idle timestamp
945     hci_connection_timestamp(conn);
946 #endif
947 
948 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
949     hci_stack->host_completed_packets = 1;
950     conn->num_packets_completed++;
951 #endif
952 
953     // handle different packet types
954     switch (acl_flags & 0x03u) {
955 
956         case 0x01: // continuation fragment
957 
958             // sanity checks
959             if (conn->acl_recombination_pos == 0u) {
960                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
961                 return;
962             }
963             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
964                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
965                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
966                 conn->acl_recombination_pos = 0;
967                 return;
968             }
969 
970             // append fragment payload (header already stored)
971             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
972                          &packet[4], acl_length);
973             conn->acl_recombination_pos += acl_length;
974 
975             // forward complete L2CAP packet if complete.
976             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
977                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
978                 // reset recombination buffer
979                 conn->acl_recombination_length = 0;
980                 conn->acl_recombination_pos = 0;
981             }
982             break;
983 
984         case 0x02: { // first fragment
985 
986             // sanity check
987             if (conn->acl_recombination_pos) {
988                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
989                 conn->acl_recombination_pos = 0;
990             }
991 
992             // peek into L2CAP packet!
993             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
994 
995             // compare fragment size to L2CAP packet size
996             if (acl_length >= (l2cap_length + 4u)){
997                 // forward fragment as L2CAP packet
998                 hci_emit_acl_packet(packet, acl_length + 4u);
999             } else {
1000 
1001                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1002                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1003                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1004                     return;
1005                 }
1006 
1007                 // store first fragment and tweak acl length for complete package
1008                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1009                              packet, acl_length + 4u);
1010                 conn->acl_recombination_pos    = acl_length + 4u;
1011                 conn->acl_recombination_length = l2cap_length;
1012                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1013             }
1014             break;
1015 
1016         }
1017         default:
1018             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1019             return;
1020     }
1021 
1022     // execute main loop
1023     hci_run();
1024 }
1025 
1026 static void hci_connection_stop_timer(hci_connection_t * conn){
1027     btstack_run_loop_remove_timer(&conn->timeout);
1028 #ifdef ENABLE_CLASSIC
1029     btstack_run_loop_remove_timer(&conn->timeout_sco);
1030 #endif
1031 }
1032 
1033 static void hci_shutdown_connection(hci_connection_t *conn){
1034     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1035 
1036 #ifdef ENABLE_CLASSIC
1037 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1038     bd_addr_type_t addr_type = conn->address_type;
1039 #endif
1040 #ifdef HAVE_SCO_TRANSPORT
1041     hci_con_handle_t con_handle = conn->con_handle;
1042 #endif
1043 #endif
1044 
1045     hci_connection_stop_timer(conn);
1046 
1047     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1048     btstack_memory_hci_connection_free( conn );
1049 
1050     // now it's gone
1051     hci_emit_nr_connections_changed();
1052 
1053 #ifdef ENABLE_CLASSIC
1054 #ifdef ENABLE_SCO_OVER_HCI
1055     // update SCO
1056     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1057         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1058     }
1059 #endif
1060 #ifdef HAVE_SCO_TRANSPORT
1061     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1062         hci_stack->sco_transport->close(con_handle);
1063     }
1064 #endif
1065 #endif
1066 }
1067 
1068 #ifdef ENABLE_CLASSIC
1069 
1070 static const uint16_t packet_type_sizes[] = {
1071     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1072     HCI_ACL_DH1_SIZE, 0, 0, 0,
1073     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1074     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1075 };
1076 static const uint8_t  packet_type_feature_requirement_bit[] = {
1077      0, // 3 slot packets
1078      1, // 5 slot packets
1079     25, // EDR 2 mpbs
1080     26, // EDR 3 mbps
1081     39, // 3 slot EDR packts
1082     40, // 5 slot EDR packet
1083 };
1084 static const uint16_t packet_type_feature_packet_mask[] = {
1085     0x0f00, // 3 slot packets
1086     0xf000, // 5 slot packets
1087     0x1102, // EDR 2 mpbs
1088     0x2204, // EDR 3 mbps
1089     0x0300, // 3 slot EDR packts
1090     0x3000, // 5 slot EDR packet
1091 };
1092 
1093 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1094     // enable packet types based on size
1095     uint16_t packet_types = 0;
1096     unsigned int i;
1097     for (i=0;i<16;i++){
1098         if (packet_type_sizes[i] == 0) continue;
1099         if (packet_type_sizes[i] <= buffer_size){
1100             packet_types |= 1 << i;
1101         }
1102     }
1103     // disable packet types due to missing local supported features
1104     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1105         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1106         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1107         if (feature_set) continue;
1108         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1109         packet_types &= ~packet_type_feature_packet_mask[i];
1110     }
1111     // flip bits for "may not be used"
1112     packet_types ^= 0x3306;
1113     return packet_types;
1114 }
1115 
1116 uint16_t hci_usable_acl_packet_types(void){
1117     return hci_stack->packet_types;
1118 }
1119 #endif
1120 
1121 uint8_t* hci_get_outgoing_packet_buffer(void){
1122     // hci packet buffer is >= acl data packet length
1123     return hci_stack->hci_packet_buffer;
1124 }
1125 
1126 uint16_t hci_max_acl_data_packet_length(void){
1127     return hci_stack->acl_data_packet_length;
1128 }
1129 
1130 #ifdef ENABLE_CLASSIC
1131 bool hci_extended_sco_link_supported(void){
1132     // No. 31, byte 3, bit 7
1133     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1134 }
1135 #endif
1136 
1137 bool hci_non_flushable_packet_boundary_flag_supported(void){
1138     // No. 54, byte 6, bit 6
1139     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1140 }
1141 
1142 static int gap_ssp_supported(void){
1143     // No. 51, byte 6, bit 3
1144     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1145 }
1146 
1147 static int hci_classic_supported(void){
1148 #ifdef ENABLE_CLASSIC
1149     // No. 37, byte 4, bit 5, = No BR/EDR Support
1150     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1151 #else
1152     return 0;
1153 #endif
1154 }
1155 
1156 static int hci_le_supported(void){
1157 #ifdef ENABLE_BLE
1158     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1159     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1160 #else
1161     return 0;
1162 #endif
1163 }
1164 
1165 #ifdef ENABLE_BLE
1166 
1167 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1168     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1169         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1170     } else {
1171         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1172     }
1173 }
1174 
1175 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1176     *addr_type = hci_stack->le_own_addr_type;
1177     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1178 }
1179 
1180 #ifdef ENABLE_LE_PERIPHERAL
1181 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1182     *addr_type = hci_stack->le_advertisements_own_addr_type;
1183     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1184 };
1185 #endif
1186 
1187 #ifdef ENABLE_LE_CENTRAL
1188 
1189 /**
1190  * @brief Get own addr type and address used for LE connections (Central)
1191  */
1192 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1193     *addr_type = hci_stack->le_connection_own_addr_type;
1194     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1195 }
1196 
1197 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1198 
1199     int offset = 3;
1200     int num_reports = packet[offset];
1201     offset += 1;
1202 
1203     int i;
1204     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1205     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1206     for (i=0; (i<num_reports) && (offset < size);i++){
1207         // sanity checks on data_length:
1208         uint8_t data_length = packet[offset + 8];
1209         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1210         if ((offset + 9u + data_length + 1u) > size)    return;
1211         // setup event
1212         uint8_t event_size = 10u + data_length;
1213         int pos = 0;
1214         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1215         event[pos++] = event_size;
1216         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1217         offset += 8;
1218         pos += 8;
1219         event[pos++] = packet[offset + 1 + data_length]; // rssi
1220         event[pos++] = data_length;
1221         offset++;
1222         (void)memcpy(&event[pos], &packet[offset], data_length);
1223         pos +=    data_length;
1224         offset += data_length + 1u; // rssi
1225         hci_emit_event(event, pos, 1);
1226     }
1227 }
1228 #endif
1229 #endif
1230 
1231 #ifdef ENABLE_BLE
1232 #ifdef ENABLE_LE_PERIPHERAL
1233 static void hci_update_advertisements_enabled_for_current_roles(void){
1234     if (hci_stack->le_advertisements_enabled){
1235         // get number of active le slave connections
1236         int num_slave_connections = 0;
1237         btstack_linked_list_iterator_t it;
1238         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1239         while (btstack_linked_list_iterator_has_next(&it)){
1240             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1241             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1242             if (con->state != OPEN) continue;
1243             if (con->role  != HCI_ROLE_SLAVE) continue;
1244             if (!hci_is_le_connection(con)) continue;
1245             num_slave_connections++;
1246         }
1247         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1248         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1249     } else {
1250         hci_stack->le_advertisements_enabled_for_current_roles = false;
1251     }
1252 }
1253 #endif
1254 #endif
1255 
1256 #ifdef ENABLE_CLASSIC
1257 static void gap_run_set_local_name(void){
1258     hci_reserve_packet_buffer();
1259     uint8_t * packet = hci_stack->hci_packet_buffer;
1260     // construct HCI Command and send
1261     uint16_t opcode = hci_write_local_name.opcode;
1262     hci_stack->last_cmd_opcode = opcode;
1263     packet[0] = opcode & 0xff;
1264     packet[1] = opcode >> 8;
1265     packet[2] = DEVICE_NAME_LEN;
1266     memset(&packet[3], 0, DEVICE_NAME_LEN);
1267     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1268     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1269     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1270     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1271     // expand '00:00:00:00:00:00' in name with bd_addr
1272     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1273     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1274 }
1275 
1276 static void gap_run_set_eir_data(void){
1277     hci_reserve_packet_buffer();
1278     uint8_t * packet = hci_stack->hci_packet_buffer;
1279     // construct HCI Command in-place and send
1280     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1281     hci_stack->last_cmd_opcode = opcode;
1282     uint16_t offset = 0;
1283     packet[offset++] = opcode & 0xff;
1284     packet[offset++] = opcode >> 8;
1285     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1286     packet[offset++] = 0;  // FEC not required
1287     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1288     if (hci_stack->eir_data){
1289         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1290         ad_context_t context;
1291         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1292             uint8_t data_type   = ad_iterator_get_data_type(&context);
1293             uint8_t size        = ad_iterator_get_data_len(&context);
1294             const uint8_t *data = ad_iterator_get_data(&context);
1295             // copy item
1296             packet[offset++] = size + 1;
1297             packet[offset++] = data_type;
1298             memcpy(&packet[offset], data, size);
1299             // update name item
1300             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1301                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1302             }
1303             offset += size;
1304         }
1305     } else {
1306         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1307         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1308         packet[offset++] = bytes_to_copy + 1;
1309         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1310         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1311         // expand '00:00:00:00:00:00' in name with bd_addr
1312         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1313     }
1314     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1315 }
1316 
1317 static void hci_run_gap_tasks_classic(void){
1318     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1319         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1320         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1321         return;
1322     }
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1325         gap_run_set_local_name();
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1330         gap_run_set_eir_data();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1335         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1336         return;
1337     }
1338     // write page scan activity
1339     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1340         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1341         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1342         return;
1343     }
1344     // write page scan type
1345     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1346         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1347         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1348         return;
1349     }
1350     // send scan enable
1351     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1352         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1353         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1354         return;
1355     }
1356 }
1357 #endif
1358 
1359 #ifndef HAVE_HOST_CONTROLLER_API
1360 
1361 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1362     if (!hci_stack->config) return 0;
1363     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1364     // Limit baud rate for Broadcom chipsets to 3 mbps
1365     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1366         baud_rate = 3000000;
1367     }
1368     return baud_rate;
1369 }
1370 
1371 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1372     UNUSED(ds);
1373 
1374     switch (hci_stack->substate){
1375         case HCI_INIT_W4_SEND_RESET:
1376             log_info("Resend HCI Reset");
1377             hci_stack->substate = HCI_INIT_SEND_RESET;
1378             hci_stack->num_cmd_packets = 1;
1379             hci_run();
1380             break;
1381         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1382             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1383             if (hci_stack->hci_transport->reset_link){
1384                 hci_stack->hci_transport->reset_link();
1385             }
1386 
1387             /* fall through */
1388 
1389         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1390             log_info("Resend HCI Reset - CSR Warm Boot");
1391             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1392             hci_stack->num_cmd_packets = 1;
1393             hci_run();
1394             break;
1395         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1396             if (hci_stack->hci_transport->set_baudrate){
1397                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1398                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1399                 hci_stack->hci_transport->set_baudrate(baud_rate);
1400             }
1401             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1402             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1403                 if (hci_stack->hci_transport->reset_link){
1404                     log_info("Link Reset");
1405                     hci_stack->hci_transport->reset_link();
1406                 }
1407                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1408                 hci_run();
1409             }
1410             break;
1411         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1412             // otherwise continue
1413             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1414             hci_send_cmd(&hci_read_local_supported_commands);
1415             break;
1416         default:
1417             break;
1418     }
1419 }
1420 #endif
1421 
1422 static void hci_initializing_next_state(void){
1423     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1424 }
1425 
1426 // assumption: hci_can_send_command_packet_now() == true
1427 static void hci_initializing_run(void){
1428     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1429 
1430     bool need_baud_change = false;
1431 
1432 #ifndef HAVE_HOST_CONTROLLER_API
1433     need_baud_change = hci_stack->config
1434             && hci_stack->chipset
1435             && hci_stack->chipset->set_baudrate_command
1436             && hci_stack->hci_transport->set_baudrate
1437             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1438 #endif
1439 
1440     switch (hci_stack->substate){
1441         case HCI_INIT_SEND_RESET:
1442             hci_state_reset();
1443 
1444 #ifndef HAVE_HOST_CONTROLLER_API
1445             // prepare reset if command complete not received in 100ms
1446             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1447             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1448             btstack_run_loop_add_timer(&hci_stack->timeout);
1449 #endif
1450             // send command
1451             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1452             hci_send_cmd(&hci_reset);
1453             break;
1454         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1455             hci_send_cmd(&hci_read_local_version_information);
1456             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1457             break;
1458         case HCI_INIT_SEND_READ_LOCAL_NAME:
1459             hci_send_cmd(&hci_read_local_name);
1460             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1461             break;
1462 
1463 #ifndef HAVE_HOST_CONTROLLER_API
1464         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1465             hci_state_reset();
1466             // prepare reset if command complete not received in 100ms
1467             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1468             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1469             btstack_run_loop_add_timer(&hci_stack->timeout);
1470             // send command
1471             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1472             hci_send_cmd(&hci_reset);
1473             break;
1474         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1475             hci_state_reset();
1476             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1477             hci_send_cmd(&hci_reset);
1478             break;
1479         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1480             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1481             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1482             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1483             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1484             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1485             break;
1486         }
1487         case HCI_INIT_SET_BD_ADDR:
1488             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1489             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1490             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1491             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1492             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1493             break;
1494         case HCI_INIT_SEND_BAUD_CHANGE:
1495             if (need_baud_change) {
1496                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1497                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1498                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1499                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1500                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1501                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1502                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1503                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1504                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1505                     btstack_run_loop_add_timer(&hci_stack->timeout);
1506                }
1507                break;
1508             }
1509 
1510             /* fall through */
1511 
1512         case HCI_INIT_CUSTOM_INIT:
1513             // Custom initialization
1514             if (hci_stack->chipset && hci_stack->chipset->next_command){
1515                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1516                 bool send_cmd = false;
1517                 switch (hci_stack->chipset_result){
1518                     case BTSTACK_CHIPSET_VALID_COMMAND:
1519                         send_cmd = true;
1520                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1521                         break;
1522                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1523                         send_cmd = true;
1524                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1525                         log_info("CSR Warm Boot");
1526                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1527                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1528                         btstack_run_loop_add_timer(&hci_stack->timeout);
1529                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1530                             && hci_stack->config
1531                             && hci_stack->chipset
1532                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1533                             && hci_stack->hci_transport->set_baudrate
1534                             && hci_transport_uart_get_main_baud_rate()){
1535                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1536                         } else {
1537                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1538                         }
1539                         break;
1540                     default:
1541                         break;
1542                 }
1543 
1544                 if (send_cmd){
1545                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1546                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1547                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1548                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1549                     break;
1550                 }
1551                 log_info("Init script done");
1552 
1553                 // Init script download on Broadcom chipsets causes:
1554                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1555                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1556                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1557 
1558                     // - baud rate to reset, restore UART baud rate if needed
1559                     if (need_baud_change) {
1560                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1561                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1562                         hci_stack->hci_transport->set_baudrate(baud_rate);
1563                     }
1564 
1565                     uint16_t bcm_delay_ms = 300;
1566                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1567                     //   -> Work around: wait here.
1568                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1569                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1570                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1571                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1572                     btstack_run_loop_add_timer(&hci_stack->timeout);
1573                     break;
1574                 }
1575             }
1576             /* fall through */
1577 #endif
1578 
1579         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1580             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1581             hci_send_cmd(&hci_read_local_supported_commands);
1582             break;
1583         case HCI_INIT_READ_BD_ADDR:
1584             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1585             hci_send_cmd(&hci_read_bd_addr);
1586             break;
1587         case HCI_INIT_READ_BUFFER_SIZE:
1588             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1589             hci_send_cmd(&hci_read_buffer_size);
1590             break;
1591         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1592             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1593             hci_send_cmd(&hci_read_local_supported_features);
1594             break;
1595 
1596 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1597         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1598             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1599             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1600             break;
1601         case HCI_INIT_HOST_BUFFER_SIZE:
1602             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1603             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1604                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1605             break;
1606 #endif
1607 
1608         case HCI_INIT_SET_EVENT_MASK:
1609             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1610             if (hci_le_supported()){
1611                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1612             } else {
1613                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1614                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1615             }
1616             break;
1617 
1618 #ifdef ENABLE_CLASSIC
1619         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1620             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1621             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1622             break;
1623         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1624             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1625             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1626             break;
1627         case HCI_INIT_WRITE_INQUIRY_MODE:
1628             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1629             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1630             break;
1631         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1632             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1633 			hci_stack->secure_connections_active = true;
1634             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1635             break;
1636         // only sent if ENABLE_SCO_OVER_HCI is defined
1637         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1638             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1639             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1640             break;
1641         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1642             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1643             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1644             break;
1645         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1646         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1647             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1648 #ifdef ENABLE_SCO_OVER_HCI
1649             log_info("BCM: Route SCO data via HCI transport");
1650             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1651 #endif
1652 #ifdef ENABLE_SCO_OVER_PCM
1653             log_info("BCM: Route SCO data via PCM interface");
1654 #ifdef ENABLE_BCM_PCM_WBS
1655             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1656             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1657 #else
1658             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1659             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1660 #endif
1661 #endif
1662             break;
1663 #ifdef ENABLE_SCO_OVER_PCM
1664         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1665             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1666             log_info("BCM: Config PCM interface for I2S");
1667 #ifdef ENABLE_BCM_PCM_WBS
1668             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1669             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1670 #else
1671             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1672             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1673 #endif
1674             break;
1675 #endif
1676 #endif
1677 
1678 #ifdef ENABLE_BLE
1679         // LE INIT
1680         case HCI_INIT_LE_READ_BUFFER_SIZE:
1681             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1682             hci_send_cmd(&hci_le_read_buffer_size);
1683             break;
1684         case HCI_INIT_LE_SET_EVENT_MASK:
1685             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1686             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1687             break;
1688         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1689             // LE Supported Host = 1, Simultaneous Host = 0
1690             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1691             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1692             break;
1693 #endif
1694 
1695 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1696         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1697             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1698             hci_send_cmd(&hci_le_read_maximum_data_length);
1699             break;
1700         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1701             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1702             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1703             break;
1704 #endif
1705 
1706 #ifdef ENABLE_LE_CENTRAL
1707         case HCI_INIT_READ_WHITE_LIST_SIZE:
1708             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1709             hci_send_cmd(&hci_le_read_white_list_size);
1710             break;
1711         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1712             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1713             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);
1714             break;
1715 #endif
1716         default:
1717             return;
1718     }
1719 }
1720 
1721 static void hci_init_done(void){
1722 #ifdef ENABLE_CLASSIC
1723     // init sequence complete, check if GAP Tasks are completed
1724     if (hci_stack->gap_tasks != 0) {
1725         hci_run_gap_tasks_classic();
1726         return;
1727     }
1728 #endif
1729 
1730     // done. tell the app
1731     log_info("hci_init_done -> HCI_STATE_WORKING");
1732     hci_stack->state = HCI_STATE_WORKING;
1733     hci_emit_state();
1734     hci_run();
1735 }
1736 
1737 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1738     bool command_completed = false;
1739     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1740         uint16_t opcode = little_endian_read_16(packet,3);
1741         if (opcode == hci_stack->last_cmd_opcode){
1742             command_completed = true;
1743             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1744         } else {
1745             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1746         }
1747     }
1748 
1749     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1750         uint8_t  status = packet[2];
1751         uint16_t opcode = little_endian_read_16(packet,4);
1752         if (opcode == hci_stack->last_cmd_opcode){
1753             if (status){
1754                 command_completed = true;
1755                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1756             } else {
1757                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1758             }
1759         } else {
1760             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1761         }
1762     }
1763 #ifndef HAVE_HOST_CONTROLLER_API
1764     // Vendor == CSR
1765     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1766         // TODO: track actual command
1767         command_completed = true;
1768     }
1769 
1770     // Vendor == Toshiba
1771     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1772         // TODO: track actual command
1773         command_completed = true;
1774         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1775         hci_stack->num_cmd_packets = 1;
1776     }
1777 #endif
1778 
1779     return command_completed;
1780 }
1781 
1782 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1783 
1784     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1785 
1786     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1787 
1788 #ifndef HAVE_HOST_CONTROLLER_API
1789 
1790     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1791     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1792     //
1793     // HCI Reset
1794     // Timeout 100 ms
1795     // HCI Reset
1796     // Command Complete Reset
1797     // HCI Read Local Version Information
1798     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1799     // hang...
1800     //
1801     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1802     if (!command_completed
1803             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1804             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1805 
1806         uint16_t opcode = little_endian_read_16(packet,3);
1807         if (opcode == hci_reset.opcode){
1808             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1809             return;
1810         }
1811     }
1812 
1813     // CSR & H5
1814     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1815     if (!command_completed
1816             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1817             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1818 
1819         uint16_t opcode = little_endian_read_16(packet,3);
1820         if (opcode == hci_reset.opcode){
1821             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1822             return;
1823         }
1824     }
1825 
1826     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1827     // fix: Correct substate and behave as command below
1828     if (command_completed){
1829         switch (hci_stack->substate){
1830             case HCI_INIT_SEND_RESET:
1831                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1832                 break;
1833             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1834                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1835                 break;
1836             default:
1837                 break;
1838         }
1839     }
1840 
1841 #endif
1842 
1843     if (!command_completed) return;
1844 
1845     bool need_baud_change = false;
1846     bool need_addr_change = false;
1847 
1848 #ifndef HAVE_HOST_CONTROLLER_API
1849     need_baud_change = hci_stack->config
1850                         && hci_stack->chipset
1851                         && hci_stack->chipset->set_baudrate_command
1852                         && hci_stack->hci_transport->set_baudrate
1853                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1854 
1855     need_addr_change = hci_stack->custom_bd_addr_set
1856                         && hci_stack->chipset
1857                         && hci_stack->chipset->set_bd_addr_command;
1858 #endif
1859 
1860     switch(hci_stack->substate){
1861 
1862 #ifndef HAVE_HOST_CONTROLLER_API
1863         case HCI_INIT_SEND_RESET:
1864             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1865             // fix: just correct substate and behave as command below
1866 
1867             /* fall through */
1868 #endif
1869 
1870         case HCI_INIT_W4_SEND_RESET:
1871             btstack_run_loop_remove_timer(&hci_stack->timeout);
1872             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1873             return;
1874 
1875 #ifndef HAVE_HOST_CONTROLLER_API
1876         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1877             // for STLC2500D, baud rate change already happened.
1878             // for others, baud rate gets changed now
1879             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1880                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1881                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1882                 hci_stack->hci_transport->set_baudrate(baud_rate);
1883             }
1884             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1885             return;
1886         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1887             btstack_run_loop_remove_timer(&hci_stack->timeout);
1888             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1889             return;
1890         case HCI_INIT_W4_CUSTOM_INIT:
1891             // repeat custom init
1892             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1893             return;
1894 #endif
1895 
1896         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1897             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1898               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1899                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1900                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1901                 return;
1902             }
1903             if (need_addr_change){
1904                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1905                 return;
1906             }
1907             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1908             return;
1909 #ifndef HAVE_HOST_CONTROLLER_API
1910         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1911             if (need_baud_change){
1912                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1913                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1914                 hci_stack->hci_transport->set_baudrate(baud_rate);
1915             }
1916             if (need_addr_change){
1917                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1918                 return;
1919             }
1920             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1921             return;
1922         case HCI_INIT_W4_SET_BD_ADDR:
1923             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1924             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1925             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1926                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1927                 return;
1928             }
1929             // skipping st warm boot
1930             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1931             return;
1932         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1933             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1934             return;
1935 #endif
1936         case HCI_INIT_W4_READ_BD_ADDR:
1937             // only read buffer size if supported
1938             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1939                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1940                 return;
1941             }
1942             // skipping read buffer size
1943             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1944             return;
1945         case HCI_INIT_W4_SET_EVENT_MASK:
1946             // skip Classic init commands for LE only chipsets
1947             if (!hci_classic_supported()){
1948 #ifdef ENABLE_BLE
1949                 if (hci_le_supported()){
1950                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1951                     return;
1952                 }
1953 #endif
1954                 log_error("Neither BR/EDR nor LE supported");
1955                 hci_init_done();
1956                 return;
1957             }
1958             if (!gap_ssp_supported()){
1959                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1960                 return;
1961             }
1962             break;
1963 #ifdef ENABLE_BLE
1964         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1965             // skip write le host if not supported (e.g. on LE only EM9301)
1966             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1967             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1968             return;
1969 
1970 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1971         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1972             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1973             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1974                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1975                 return;
1976             }
1977             // explicit fall through to reduce repetitions
1978 
1979 #ifdef ENABLE_LE_CENTRAL
1980             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1981 #else
1982             hci_init_done();
1983 #endif
1984             return;
1985 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1986 
1987 #endif  /* ENABLE_BLE */
1988 
1989         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1990             // skip write secure connections host support if not supported or disabled
1991             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1992                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1993                 return;
1994             }
1995             break;
1996 
1997 #ifdef ENABLE_SCO_OVER_HCI
1998         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1999             // skip write synchronous flow control if not supported
2000             if (hci_stack->local_supported_commands[0] & 0x04) break;
2001             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
2002 
2003             /* fall through */
2004 
2005         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2006             // skip write default erroneous data reporting if not supported
2007             if (hci_stack->local_supported_commands[0] & 0x08) break;
2008             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
2009 
2010             /* fall through */
2011 
2012         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
2013             // skip bcm set sco pcm config on non-Broadcom chipsets
2014             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
2015             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2016 
2017             /* fall through */
2018 
2019         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
2020             if (!hci_le_supported()){
2021                 // SKIP LE init for Classic only configuration
2022                 hci_init_done();
2023                 return;
2024             }
2025             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2026             break;
2027 
2028 #else /* !ENABLE_SCO_OVER_HCI */
2029 
2030         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2031 #ifdef ENABLE_SCO_OVER_PCM
2032             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
2033                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
2034                 return;
2035             }
2036 #endif
2037             /* fall through */
2038 
2039         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
2040 #ifdef ENABLE_BLE
2041             if (hci_le_supported()){
2042                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
2043                 return;
2044             }
2045 #endif
2046             // SKIP LE init for Classic only configuration
2047             hci_init_done();
2048             return;
2049 #endif /* ENABLE_SCO_OVER_HCI */
2050 
2051 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2052 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2053         // Response to command before init done state -> init done
2054         case (HCI_INIT_DONE-1):
2055             hci_init_done();
2056             return;
2057 #endif
2058 
2059         default:
2060             break;
2061     }
2062     hci_initializing_next_state();
2063 }
2064 
2065 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2066     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2067     bd_addr_t bd_address;
2068     (void)memcpy(&bd_address, conn->address, 6);
2069 
2070 #ifdef ENABLE_CLASSIC
2071     // cache needed data
2072     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2073 #endif
2074 
2075     // connection failed, remove entry
2076     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2077     btstack_memory_hci_connection_free( conn );
2078 
2079 #ifdef ENABLE_CLASSIC
2080     // notify client if dedicated bonding
2081     if (notify_dedicated_bonding_failed){
2082         log_info("hci notify_dedicated_bonding_failed");
2083         hci_emit_dedicated_bonding_result(bd_address, status);
2084     }
2085 
2086     // if authentication error, also delete link key
2087     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2088         gap_drop_link_key_for_bd_addr(bd_address);
2089     }
2090 #else
2091     UNUSED(status);
2092 #endif
2093 }
2094 
2095 #ifdef ENABLE_CLASSIC
2096 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2097     // SSP Controller
2098     if (features[6] & (1 << 3)){
2099         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2100     }
2101     // eSCO
2102     if (features[3] & (1<<7)){
2103         conn->remote_supported_features[0] |= 1;
2104     }
2105     // Extended features
2106     if (features[7] & (1<<7)){
2107         conn->remote_supported_features[0] |= 2;
2108     }
2109 }
2110 
2111 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2112     // SSP Host
2113     if (features[0] & (1 << 0)){
2114         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2115     }
2116     // SC Host
2117     if (features[0] & (1 << 3)){
2118         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2119     }
2120 }
2121 
2122 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2123     // SC Controller
2124     if (features[1] & (1 << 0)){
2125         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2126     }
2127 }
2128 
2129 static void hci_handle_remote_features_received(hci_connection_t * conn){
2130     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2131     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2132     if (conn->bonding_flags & BONDING_DEDICATED){
2133         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2134     }
2135 }
2136 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2137     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2138     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2139 }
2140 
2141 #endif
2142 
2143 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2144     // handle BT initialization
2145     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2146         hci_initializing_event_handler(packet, size);
2147     }
2148 
2149     // help with BT sleep
2150     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2151         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2152         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2153         hci_initializing_next_state();
2154     }
2155 }
2156 
2157 #ifdef ENABLE_CLASSIC
2158 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2159     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2160     conn->encryption_key_size = encryption_key_size;
2161 
2162     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2163         conn->requested_security_level = LEVEL_0;
2164         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2165         return;
2166     }
2167 
2168     // Request Authentication if not already done
2169     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2170     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2171 }
2172 #endif
2173 
2174 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2175     UNUSED(size);
2176 
2177     uint16_t manufacturer;
2178 #ifdef ENABLE_CLASSIC
2179     hci_con_handle_t handle;
2180     hci_connection_t * conn;
2181     uint8_t status;
2182 #endif
2183     // get num cmd packets - limit to 1 to reduce complexity
2184     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2185 
2186     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2187     switch (opcode){
2188         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2189             if (packet[5]) break;
2190             // terminate, name 248 chars
2191             packet[6+248] = 0;
2192             log_info("local name: %s", &packet[6]);
2193             break;
2194         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2195             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2196             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2197                 uint16_t acl_len = little_endian_read_16(packet, 6);
2198                 uint16_t sco_len = packet[8];
2199 
2200                 // determine usable ACL/SCO payload size
2201                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2202                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2203 
2204                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2205                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2206 
2207                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2208                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2209                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2210             }
2211             break;
2212         case HCI_OPCODE_HCI_READ_RSSI:
2213             if (packet[5] == ERROR_CODE_SUCCESS){
2214                 uint8_t event[5];
2215                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2216                 event[1] = 3;
2217                 (void)memcpy(&event[2], &packet[6], 3);
2218                 hci_emit_event(event, sizeof(event), 1);
2219             }
2220             break;
2221 #ifdef ENABLE_BLE
2222         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2223             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2224             hci_stack->le_acl_packets_total_num = packet[8];
2225             // determine usable ACL payload size
2226             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2227                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2228             }
2229             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2230             break;
2231 #endif
2232 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2233         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2234             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2235             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2236             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);
2237             break;
2238 #endif
2239 #ifdef ENABLE_LE_CENTRAL
2240         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2241             hci_stack->le_whitelist_capacity = packet[6];
2242             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2243             break;
2244 #endif
2245         case HCI_OPCODE_HCI_READ_BD_ADDR:
2246             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2247             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));
2248 #ifdef ENABLE_CLASSIC
2249             if (hci_stack->link_key_db){
2250                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2251             }
2252 #endif
2253             break;
2254 #ifdef ENABLE_CLASSIC
2255         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2256             hci_emit_discoverable_enabled(hci_stack->discoverable);
2257             break;
2258         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2259             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2260                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2261                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2262                 hci_emit_event(event, sizeof(event), 1);
2263             }
2264             break;
2265 #endif
2266         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2267             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2268 
2269 #ifdef ENABLE_CLASSIC
2270             // determine usable ACL packet types based on host buffer size and supported features
2271             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2272             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2273 #endif
2274             // Classic/LE
2275             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2276             break;
2277         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2278             manufacturer = little_endian_read_16(packet, 10);
2279             // map Cypress to Broadcom
2280             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2281                 log_info("Treat Cypress as Broadcom");
2282                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2283                 little_endian_store_16(packet, 10, manufacturer);
2284             }
2285             hci_stack->manufacturer = manufacturer;
2286             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2287             break;
2288         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2289             hci_stack->local_supported_commands[0] =
2290                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2291                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2292                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2293                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2294                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2295                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2296                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2297                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2298             hci_stack->local_supported_commands[1] =
2299                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2300                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2301                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2302                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2303                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2304             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2305             break;
2306 #ifdef ENABLE_CLASSIC
2307         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2308             if (packet[5]) return;
2309             hci_stack->synchronous_flow_control_enabled = 1;
2310             break;
2311         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2312             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2313             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2314             conn   = hci_connection_for_handle(handle);
2315             if (conn != NULL) {
2316                 uint8_t key_size = 0;
2317                 if (status == 0){
2318                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2319                     log_info("Handle %04x key Size: %u", handle, key_size);
2320                 } else {
2321                     key_size = 1;
2322                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2323                 }
2324                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2325             }
2326             break;
2327         // assert pairing complete event is emitted.
2328         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2329         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2330         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2331         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2332             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2333             // lookup connection by gap pairing addr
2334             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2335             if (conn == NULL) break;
2336             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2337             break;
2338 
2339 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2340         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2341         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2342             uint8_t event[67];
2343             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2344             event[1] = 65;
2345             (void)memset(&event[2], 0, 65);
2346             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2347                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2348                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2349                     event[2] = 3;
2350                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2351                 } else {
2352                     event[2] = 1;
2353                 }
2354             }
2355             hci_emit_event(event, sizeof(event), 0);
2356             break;
2357         }
2358 
2359         // note: only needed if user does not provide OOB data
2360         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2361             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2362             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2363             if (conn == NULL) break;
2364             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2365             break;
2366 #endif
2367 #endif
2368         default:
2369             break;
2370     }
2371 }
2372 
2373 #ifdef ENABLE_BLE
2374 static void event_handle_le_connection_complete(const uint8_t * packet){
2375 	bd_addr_t addr;
2376 	bd_addr_type_t addr_type;
2377 	hci_connection_t * conn;
2378 
2379 	// Connection management
2380 	reverse_bd_addr(&packet[8], addr);
2381 	addr_type = (bd_addr_type_t)packet[7];
2382 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2383 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2384 
2385 #ifdef ENABLE_LE_CENTRAL
2386 	// handle error: error is reported only to the initiator -> outgoing connection
2387 	if (packet[3]){
2388 
2389 		// handle cancelled outgoing connection
2390 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2391 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2392 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2393 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2394 		    // reset state
2395             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2396             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2397 			// get outgoing connection conn struct for direct connect
2398 			conn = gap_get_outgoing_connection();
2399 		}
2400 
2401 		// outgoing le connection establishment is done
2402 		if (conn){
2403 			// remove entry
2404 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2405 			btstack_memory_hci_connection_free( conn );
2406 		}
2407 		return;
2408 	}
2409 #endif
2410 
2411 	// on success, both hosts receive connection complete event
2412 	if (packet[6] == HCI_ROLE_MASTER){
2413 #ifdef ENABLE_LE_CENTRAL
2414 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2415 		// note: no hci_connection_t object exists yet for connect with whitelist
2416 		if (hci_is_le_connection_type(addr_type)){
2417 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2418 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2419 		}
2420 #endif
2421 	} else {
2422 #ifdef ENABLE_LE_PERIPHERAL
2423 		// if we're slave, it was an incoming connection, advertisements have stopped
2424 		hci_stack->le_advertisements_active = false;
2425 #endif
2426 	}
2427 
2428 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2429 	if (!conn){
2430 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2431 	}
2432 
2433 	// no memory, sorry.
2434 	if (!conn){
2435 		return;
2436 	}
2437 
2438 	conn->state = OPEN;
2439 	conn->role  = packet[6];
2440 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2441 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2442 
2443 #ifdef ENABLE_LE_PERIPHERAL
2444 	if (packet[6] == HCI_ROLE_SLAVE){
2445 		hci_update_advertisements_enabled_for_current_roles();
2446 	}
2447 #endif
2448 
2449     // init unenhanced att bearer mtu
2450     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2451     conn->att_connection.mtu_exchanged = false;
2452 
2453     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2454 
2455 	// restart timer
2456 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2457 	// btstack_run_loop_add_timer(&conn->timeout);
2458 
2459 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2460 
2461 	hci_emit_nr_connections_changed();
2462 }
2463 #endif
2464 
2465 #ifdef ENABLE_CLASSIC
2466 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){
2467     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2468     // LEVEL_4 is tested by l2cap
2469     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2470     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2471     if (level >= LEVEL_3){
2472         // MITM not possible without keyboard or display
2473         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2474         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2475 
2476         // MITM possible if one side has keyboard and the other has keyboard or display
2477         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2478         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2479 
2480         // MITM not possible if one side has only display and other side has no keyboard
2481         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2482         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2483     }
2484     // LEVEL 2 requires SSP, which is a given
2485     return true;
2486 }
2487 
2488 static bool btstack_is_null(uint8_t * data, uint16_t size){
2489     uint16_t i;
2490     for (i=0; i < size ; i++){
2491         if (data[i] != 0) {
2492             return false;
2493         }
2494     }
2495     return true;
2496 }
2497 
2498 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2499     // get requested security level
2500     gap_security_level_t requested_security_level = conn->requested_security_level;
2501     if (hci_stack->gap_secure_connections_only_mode){
2502         requested_security_level = LEVEL_4;
2503     }
2504 
2505     // assess security: LEVEL 4 requires SC
2506     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2507     if ((requested_security_level == LEVEL_4) &&
2508         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2509         !hci_remote_sc_enabled(conn)){
2510         log_info("Level 4 required, but SC not supported -> abort");
2511         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2512         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2513         return;
2514     }
2515 
2516     // assess security based on io capabilities
2517     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2518         // responder: fully validate io caps of both sides as well as OOB data
2519         bool security_possible = false;
2520         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2521 
2522 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2523         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2524         // so we merge the OOB data availability
2525         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2526         if (conn->classic_oob_c_192 != NULL){
2527             have_oob_data |= 1;
2528         }
2529         if (conn->classic_oob_c_256 != NULL){
2530             have_oob_data |= 2;
2531         }
2532         // for up to Level 3, either P-192 as well as P-256 will do
2533         // if we don't support SC, then a) conn->classic_oob_c_256 will be NULL and b) remote should not report P-256 available
2534         // if remote does not SC, we should not receive P-256 data either
2535         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2536             security_possible = true;
2537         }
2538         // for Level 4, P-256 is needed
2539         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2540             security_possible = true;
2541         }
2542 #endif
2543 
2544         if (security_possible == false){
2545             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2546             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2547             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2548             return;
2549         }
2550     } else {
2551         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2552 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2553 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2554         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2555             log_info("Level 3+ required, but no input/output -> abort");
2556             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2557             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2558             return;
2559         }
2560 #endif
2561 #endif
2562     }
2563 
2564 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2565     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2566         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2567     } else {
2568         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2569     }
2570 #endif
2571 }
2572 
2573 #endif
2574 
2575 static void event_handler(uint8_t *packet, uint16_t size){
2576 
2577     uint16_t event_length = packet[1];
2578 
2579     // assert packet is complete
2580     if (size != (event_length + 2u)){
2581         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2582         return;
2583     }
2584 
2585     bd_addr_type_t addr_type;
2586     hci_con_handle_t handle;
2587     hci_connection_t * conn;
2588     int i;
2589     int create_connection_cmd;
2590 
2591 #ifdef ENABLE_CLASSIC
2592     hci_link_type_t link_type;
2593     bd_addr_t addr;
2594 #endif
2595 
2596     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2597 
2598     switch (hci_event_packet_get_type(packet)) {
2599 
2600         case HCI_EVENT_COMMAND_COMPLETE:
2601             handle_command_complete_event(packet, size);
2602             break;
2603 
2604         case HCI_EVENT_COMMAND_STATUS:
2605             // get num cmd packets - limit to 1 to reduce complexity
2606             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2607 
2608             // check command status to detected failed outgoing connections
2609             create_connection_cmd = 0;
2610 #ifdef ENABLE_CLASSIC
2611             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2612                 create_connection_cmd = 1;
2613             }
2614 #endif
2615 #ifdef ENABLE_LE_CENTRAL
2616             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2617                 create_connection_cmd = 1;
2618             }
2619 #endif
2620             if (create_connection_cmd) {
2621                 uint8_t status = hci_event_command_status_get_status(packet);
2622                 addr_type = hci_stack->outgoing_addr_type;
2623                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2624                 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);
2625 
2626                 // reset outgoing address info
2627                 memset(hci_stack->outgoing_addr, 0, 6);
2628                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2629 
2630                 // on error
2631                 if (status != ERROR_CODE_SUCCESS){
2632 #ifdef ENABLE_LE_CENTRAL
2633                     if (hci_is_le_connection_type(addr_type)){
2634                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2635                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2636                     }
2637 #endif
2638                     // error => outgoing connection failed
2639                     if (conn != NULL){
2640                         hci_handle_connection_failed(conn, status);
2641                     }
2642                 }
2643             }
2644 
2645 #ifdef ENABLE_CLASSIC
2646             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2647                 uint8_t status = hci_event_command_status_get_status(packet);
2648                 log_info("command status (inquiry), status %x", status);
2649                 if (status == ERROR_CODE_SUCCESS) {
2650                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2651                 } else {
2652                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2653                 }
2654             }
2655 #endif
2656             break;
2657 
2658         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2659             if (size < 3) return;
2660             uint16_t num_handles = packet[2];
2661             if (size != (3u + num_handles * 4u)) return;
2662             uint16_t offset = 3;
2663             for (i=0; i<num_handles;i++){
2664                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2665                 offset += 2u;
2666                 uint16_t num_packets = little_endian_read_16(packet, offset);
2667                 offset += 2u;
2668 
2669                 conn = hci_connection_for_handle(handle);
2670                 if (!conn){
2671                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2672                     continue;
2673                 }
2674 
2675                 if (conn->num_packets_sent >= num_packets){
2676                     conn->num_packets_sent -= num_packets;
2677                 } else {
2678                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2679                     conn->num_packets_sent = 0;
2680                 }
2681                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2682 
2683 #ifdef ENABLE_CLASSIC
2684                 // For SCO, we do the can_send_now_check here
2685                 hci_notify_if_sco_can_send_now();
2686 #endif
2687             }
2688             break;
2689         }
2690 
2691 #ifdef ENABLE_CLASSIC
2692         case HCI_EVENT_INQUIRY_COMPLETE:
2693             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2694                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2695                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2696                 hci_emit_event(event, sizeof(event), 1);
2697             }
2698             break;
2699         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2700             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2701                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2702             }
2703             break;
2704         case HCI_EVENT_CONNECTION_REQUEST:
2705             reverse_bd_addr(&packet[2], addr);
2706             link_type = (hci_link_type_t) packet[11];
2707 
2708             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2709             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2710                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2711                 bd_addr_copy(hci_stack->decline_addr, addr);
2712                 break;
2713             }
2714 
2715             if (hci_stack->gap_classic_accept_callback != NULL){
2716                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2717                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2718                     bd_addr_copy(hci_stack->decline_addr, addr);
2719                     break;
2720                 }
2721             }
2722 
2723             // TODO: eval COD 8-10
2724             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2725             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2726             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2727             if (!conn) {
2728                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2729             }
2730             if (!conn) {
2731                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2732                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2733                 bd_addr_copy(hci_stack->decline_addr, addr);
2734                 break;
2735             }
2736             conn->role  = HCI_ROLE_SLAVE;
2737             conn->state = RECEIVED_CONNECTION_REQUEST;
2738             // store info about eSCO
2739             if (link_type == HCI_LINK_TYPE_ESCO){
2740                 conn->remote_supported_features[0] |= 1;
2741             }
2742             hci_run();
2743             break;
2744 
2745         case HCI_EVENT_CONNECTION_COMPLETE:
2746             // Connection management
2747             reverse_bd_addr(&packet[5], addr);
2748             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2749             addr_type = BD_ADDR_TYPE_ACL;
2750             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2751             if (conn) {
2752                 if (!packet[2]){
2753                     conn->state = OPEN;
2754                     conn->con_handle = little_endian_read_16(packet, 3);
2755 
2756                     // queue get remote feature
2757                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2758 
2759                     // queue set supervision timeout if we're master
2760                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2761                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2762                     }
2763 
2764                     // restart timer
2765                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2766                     btstack_run_loop_add_timer(&conn->timeout);
2767 
2768                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2769 
2770                     hci_emit_nr_connections_changed();
2771                 } else {
2772                     // connection failed
2773                     hci_handle_connection_failed(conn, packet[2]);
2774                 }
2775             }
2776             break;
2777 
2778         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2779             reverse_bd_addr(&packet[5], addr);
2780             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2781             if (packet[2]){
2782                 // connection failed
2783                 break;
2784             }
2785             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2786             if (!conn) {
2787                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2788             }
2789             if (!conn) {
2790                 break;
2791             }
2792             conn->state = OPEN;
2793             conn->con_handle = little_endian_read_16(packet, 3);
2794 
2795 #ifdef ENABLE_SCO_OVER_HCI
2796             // update SCO
2797             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2798                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2799             }
2800             // trigger can send now
2801             if (hci_have_usb_transport()){
2802                 hci_stack->sco_can_send_now = true;
2803             }
2804 #endif
2805 #ifdef HAVE_SCO_TRANSPORT
2806             // configure sco transport
2807             if (hci_stack->sco_transport != NULL){
2808                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2809                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2810             }
2811 #endif
2812             break;
2813 
2814         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2815             handle = little_endian_read_16(packet, 3);
2816             conn = hci_connection_for_handle(handle);
2817             if (!conn) break;
2818             if (!packet[2]){
2819                 const uint8_t * features = &packet[5];
2820                 hci_handle_remote_features_page_0(conn, features);
2821 
2822                 // read extended features if possible
2823                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2824                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2825                     break;
2826                 }
2827             }
2828             hci_handle_remote_features_received(conn);
2829             break;
2830 
2831         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2832             handle = little_endian_read_16(packet, 3);
2833             conn = hci_connection_for_handle(handle);
2834             if (!conn) break;
2835             // status = ok, page = 1
2836             if (!packet[2]) {
2837                 uint8_t page_number = packet[5];
2838                 uint8_t maximum_page_number = packet[6];
2839                 const uint8_t * features = &packet[7];
2840                 bool done = false;
2841                 switch (page_number){
2842                     case 1:
2843                         hci_handle_remote_features_page_1(conn, features);
2844                         if (maximum_page_number >= 2){
2845                             // get Secure Connections (Controller) from Page 2 if available
2846                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2847                         } else {
2848                             // otherwise, assume SC (Controller) == SC (Host)
2849                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2850                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2851                             }
2852                             done = true;
2853                         }
2854                         break;
2855                     case 2:
2856                         hci_handle_remote_features_page_2(conn, features);
2857                         done = true;
2858                         break;
2859                     default:
2860                         break;
2861                 }
2862                 if (!done) break;
2863             }
2864             hci_handle_remote_features_received(conn);
2865             break;
2866 
2867         case HCI_EVENT_LINK_KEY_REQUEST:
2868 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2869             hci_event_link_key_request_get_bd_addr(packet, addr);
2870             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2871             if (!conn) break;
2872 
2873             // lookup link key in db if not cached
2874             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2875                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2876             }
2877 
2878             // response sent by hci_run()
2879             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2880 #endif
2881             break;
2882 
2883         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2884             hci_event_link_key_request_get_bd_addr(packet, addr);
2885             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2886             if (!conn) break;
2887 
2888             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2889 
2890             // CVE-2020-26555: ignore NULL link key
2891             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2892             if (btstack_is_null(&packet[8], 16)) break;
2893 
2894             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2895             // Change Connection Encryption keeps link key type
2896             if (link_key_type != CHANGED_COMBINATION_KEY){
2897                 conn->link_key_type = link_key_type;
2898             }
2899 
2900             // cache link key. link keys stored in little-endian format for legacy reasons
2901             memcpy(&conn->link_key, &packet[8], 16);
2902 
2903             // only store link key:
2904             // - if bondable enabled
2905             if (hci_stack->bondable == false) break;
2906             // - if security level sufficient
2907             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2908             // - for SSP, also check if remote side requested bonding as well
2909             if (conn->link_key_type != COMBINATION_KEY){
2910                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2911                 if (!remote_bonding){
2912                     break;
2913                 }
2914             }
2915             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2916             break;
2917         }
2918 
2919         case HCI_EVENT_PIN_CODE_REQUEST:
2920             hci_event_pin_code_request_get_bd_addr(packet, addr);
2921             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2922             if (!conn) break;
2923 
2924             hci_pairing_started(conn, false);
2925             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2926             if (!hci_stack->bondable ){
2927                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2928                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2929                 hci_run();
2930                 return;
2931             }
2932             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2933             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2934                 log_info("Level 4 required, but SC not supported -> abort");
2935                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2936                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2937                 hci_run();
2938                 return;
2939             }
2940             break;
2941 
2942         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2943             hci_event_io_capability_response_get_bd_addr(packet, addr);
2944             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2945             if (!conn) break;
2946 
2947             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2948             hci_pairing_started(conn, true);
2949             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2950             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2951 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2952             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2953 #endif
2954             break;
2955 
2956         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2957             hci_event_io_capability_response_get_bd_addr(packet, addr);
2958             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2959             if (!conn) break;
2960 
2961             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2962             hci_connection_timestamp(conn);
2963             hci_pairing_started(conn, true);
2964             break;
2965 
2966 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2967         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2968             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2969             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2970             if (!conn) break;
2971 
2972             hci_connection_timestamp(conn);
2973 
2974             hci_pairing_started(conn, true);
2975 
2976             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2977             break;
2978 #endif
2979 
2980         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2981             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2982             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2983             if (!conn) break;
2984             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2985                 if (hci_stack->ssp_auto_accept){
2986                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2987                 };
2988             } else {
2989                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2990                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2991                 // don't forward event to app
2992                 hci_run();
2993                 return;
2994             }
2995             break;
2996 
2997         case HCI_EVENT_USER_PASSKEY_REQUEST:
2998             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2999             if (hci_stack->ssp_auto_accept){
3000                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
3001             };
3002             break;
3003 
3004         case HCI_EVENT_MODE_CHANGE:
3005             handle = hci_event_mode_change_get_handle(packet);
3006             conn = hci_connection_for_handle(handle);
3007             if (!conn) break;
3008             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3009             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3010             break;
3011 #endif
3012 
3013         case HCI_EVENT_ENCRYPTION_CHANGE:
3014             handle = hci_event_encryption_change_get_connection_handle(packet);
3015             conn = hci_connection_for_handle(handle);
3016             if (!conn) break;
3017             if (hci_event_encryption_change_get_status(packet) == 0u) {
3018                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3019                 if (encryption_enabled){
3020                     if (hci_is_le_connection(conn)){
3021                         // For LE, we accept connection as encrypted
3022                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3023                     }
3024 #ifdef ENABLE_CLASSIC
3025                     else {
3026 
3027                         // dedicated bonding: send result and disconnect
3028                         if (conn->bonding_flags & BONDING_DEDICATED){
3029                             conn->bonding_flags &= ~BONDING_DEDICATED;
3030                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3031                             conn->bonding_status = packet[2];
3032                             break;
3033                         }
3034 
3035                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3036                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3037                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3038                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3039                             log_info("SC during pairing, but only E0 now -> abort");
3040                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3041                             break;
3042                         }
3043 
3044                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3045                         if (connected_uses_aes_ccm){
3046                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3047                         }
3048 
3049 #ifdef ENABLE_TESTING_SUPPORT
3050                         // work around for issue with PTS dongle
3051                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3052 #endif
3053 
3054                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3055                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3056                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3057                         } else {
3058                             // if not, pretend everything is perfect
3059                             hci_handle_read_encryption_key_size_complete(conn, 16);
3060                         }
3061                     }
3062 #endif
3063                 } else {
3064                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3065                 }
3066             }
3067 
3068             break;
3069 
3070 #ifdef ENABLE_CLASSIC
3071         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3072             handle = hci_event_authentication_complete_get_connection_handle(packet);
3073             conn = hci_connection_for_handle(handle);
3074             if (!conn) break;
3075 
3076             // clear authentication active flag
3077             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3078             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3079 
3080             // authenticated only if auth status == 0
3081             if (hci_event_authentication_complete_get_status(packet) == 0){
3082                 // authenticated
3083                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3084 
3085                 // If not already encrypted, start encryption
3086                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3087                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3088                     break;
3089                 }
3090             }
3091 
3092             // emit updated security level
3093             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3094             break;
3095 
3096         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3097             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3098             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3099             if (!conn) break;
3100 
3101             // treat successfully paired connection as authenticated
3102             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3103                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3104             }
3105 
3106             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3107             break;
3108 #endif
3109 
3110         // HCI_EVENT_DISCONNECTION_COMPLETE
3111         // has been split, to first notify stack before shutting connection down
3112         // see end of function, too.
3113         case HCI_EVENT_DISCONNECTION_COMPLETE:
3114             if (packet[2]) break;   // status != 0
3115             handle = little_endian_read_16(packet, 3);
3116             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3117             if (hci_stack->acl_fragmentation_total_size > 0u) {
3118                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3119                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3120                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3121                     hci_stack->acl_fragmentation_total_size = 0;
3122                     hci_stack->acl_fragmentation_pos = 0;
3123                     if (release_buffer){
3124                         hci_release_packet_buffer();
3125                     }
3126                 }
3127             }
3128 
3129             conn = hci_connection_for_handle(handle);
3130             if (!conn) break;
3131 #ifdef ENABLE_CLASSIC
3132             // pairing failed if it was ongoing
3133             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3134 #endif
3135 
3136             // emit dedicatd bonding event
3137             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3138                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3139             }
3140 
3141             // mark connection for shutdown, stop timers, reset state
3142             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3143             hci_connection_stop_timer(conn);
3144             hci_connection_init(conn);
3145 
3146 #ifdef ENABLE_BLE
3147 #ifdef ENABLE_LE_PERIPHERAL
3148             // re-enable advertisements for le connections if active
3149             if (hci_is_le_connection(conn)){
3150                 hci_update_advertisements_enabled_for_current_roles();
3151             }
3152 #endif
3153 #endif
3154             break;
3155 
3156         case HCI_EVENT_HARDWARE_ERROR:
3157             log_error("Hardware Error: 0x%02x", packet[2]);
3158             if (hci_stack->hardware_error_callback){
3159                 (*hci_stack->hardware_error_callback)(packet[2]);
3160             } else {
3161                 // if no special requests, just reboot stack
3162                 hci_power_control_off();
3163                 hci_power_control_on();
3164             }
3165             break;
3166 
3167 #ifdef ENABLE_CLASSIC
3168         case HCI_EVENT_ROLE_CHANGE:
3169             if (packet[2]) break;   // status != 0
3170             reverse_bd_addr(&packet[3], addr);
3171             addr_type = BD_ADDR_TYPE_ACL;
3172             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3173             if (!conn) break;
3174             conn->role = packet[9];
3175             break;
3176 #endif
3177 
3178         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3179             // release packet buffer only for asynchronous transport and if there are not further fragements
3180             if (hci_transport_synchronous()) {
3181                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3182                 return; // instead of break: to avoid re-entering hci_run()
3183             }
3184             hci_stack->acl_fragmentation_tx_active = 0;
3185             if (hci_stack->acl_fragmentation_total_size) break;
3186             hci_release_packet_buffer();
3187 
3188             // L2CAP receives this event via the hci_emit_event below
3189 
3190 #ifdef ENABLE_CLASSIC
3191             // For SCO, we do the can_send_now_check here
3192             hci_notify_if_sco_can_send_now();
3193 #endif
3194             break;
3195 
3196 #ifdef ENABLE_CLASSIC
3197         case HCI_EVENT_SCO_CAN_SEND_NOW:
3198             // For SCO, we do the can_send_now_check here
3199             hci_stack->sco_can_send_now = true;
3200             hci_notify_if_sco_can_send_now();
3201             return;
3202 
3203         // explode inquriy results for easier consumption
3204         case HCI_EVENT_INQUIRY_RESULT:
3205         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3206         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3207             gap_inquiry_explode(packet, size);
3208             break;
3209 #endif
3210 
3211 #ifdef ENABLE_BLE
3212         case HCI_EVENT_LE_META:
3213             switch (packet[2]){
3214 #ifdef ENABLE_LE_CENTRAL
3215                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3216                     // log_info("advertising report received");
3217                     if (!hci_stack->le_scanning_enabled) break;
3218                     le_handle_advertisement_report(packet, size);
3219                     break;
3220 #endif
3221                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3222 					event_handle_le_connection_complete(packet);
3223                     break;
3224 
3225                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3226                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3227                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3228                     conn = hci_connection_for_handle(handle);
3229                     if (!conn) break;
3230                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3231                     break;
3232 
3233                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3234                     // connection
3235                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3236                     conn = hci_connection_for_handle(handle);
3237                     if (conn) {
3238                         // read arguments
3239                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3240                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3241                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3242                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3243 
3244                         // validate against current connection parameter range
3245                         le_connection_parameter_range_t existing_range;
3246                         gap_get_connection_parameter_range(&existing_range);
3247                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3248                         if (update_parameter){
3249                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3250                             conn->le_conn_interval_min = le_conn_interval_min;
3251                             conn->le_conn_interval_max = le_conn_interval_max;
3252                             conn->le_conn_latency = le_conn_latency;
3253                             conn->le_supervision_timeout = le_supervision_timeout;
3254                         } else {
3255                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3256                         }
3257                     }
3258                     break;
3259 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3260                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3261                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3262                     conn = hci_connection_for_handle(handle);
3263                     if (conn) {
3264                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3265                     }
3266                     break;
3267 #endif
3268                 default:
3269                     break;
3270             }
3271             break;
3272 #endif
3273         case HCI_EVENT_VENDOR_SPECIFIC:
3274             // Vendor specific commands often create vendor specific event instead of num completed packets
3275             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3276             switch (hci_stack->manufacturer){
3277                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3278                     hci_stack->num_cmd_packets = 1;
3279                     break;
3280                 default:
3281                     break;
3282             }
3283             break;
3284         default:
3285             break;
3286     }
3287 
3288     handle_event_for_current_stack_state(packet, size);
3289 
3290     // notify upper stack
3291 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3292 
3293     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3294     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3295 		handle = little_endian_read_16(packet, 3);
3296 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3297 		// discard connection if app did not trigger a reconnect in the event handler
3298 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3299 			hci_shutdown_connection(aConn);
3300 		}
3301     }
3302 
3303 	// execute main loop
3304 	hci_run();
3305 }
3306 
3307 #ifdef ENABLE_CLASSIC
3308 
3309 #ifdef ENABLE_SCO_OVER_HCI
3310 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3311 static void sco_schedule_tx(hci_connection_t * conn);
3312 
3313 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3314     log_debug("SCO TX Timeout");
3315     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3316     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3317     if (!conn) return;
3318 
3319     // trigger send
3320     conn->sco_tx_ready = 1;
3321     // extra packet if CVSD but SCO buffer is too short
3322     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3323         conn->sco_tx_ready++;
3324     }
3325     hci_notify_if_sco_can_send_now();
3326 }
3327 
3328 
3329 #define SCO_TX_AFTER_RX_MS (6)
3330 
3331 static void sco_schedule_tx(hci_connection_t * conn){
3332 
3333     uint32_t now = btstack_run_loop_get_time_ms();
3334     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3335     int time_delta_ms = sco_tx_ms - now;
3336 
3337     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3338 
3339     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3340     btstack_run_loop_remove_timer(timer);
3341     btstack_run_loop_set_timer(timer, time_delta_ms);
3342     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3343     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3344     btstack_run_loop_add_timer(timer);
3345 }
3346 #endif
3347 
3348 static void sco_handler(uint8_t * packet, uint16_t size){
3349     // lookup connection struct
3350     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3351     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3352     if (!conn) return;
3353 
3354 #ifdef ENABLE_SCO_OVER_HCI
3355     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3356     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3357         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3358             packet[2] = 0x3c;
3359             memmove(&packet[3], &packet[23], 63);
3360             size = 63;
3361         }
3362     }
3363 
3364     if (hci_have_usb_transport()){
3365         // Nothing to do
3366     } else {
3367         // 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);
3368         if (hci_stack->synchronous_flow_control_enabled == 0){
3369             uint32_t now = btstack_run_loop_get_time_ms();
3370 
3371             if (!conn->sco_rx_valid){
3372                 // ignore first 10 packets
3373                 conn->sco_rx_count++;
3374                 // log_debug("sco rx count %u", conn->sco_rx_count);
3375                 if (conn->sco_rx_count == 10) {
3376                     // use first timestamp as is and pretent it just started
3377                     conn->sco_rx_ms = now;
3378                     conn->sco_rx_valid = 1;
3379                     conn->sco_rx_count = 0;
3380                     sco_schedule_tx(conn);
3381                 }
3382             } else {
3383                 // track expected arrival timme
3384                 conn->sco_rx_count++;
3385                 conn->sco_rx_ms += 7;
3386                 int delta = (int32_t) (now - conn->sco_rx_ms);
3387                 if (delta > 0){
3388                     conn->sco_rx_ms++;
3389                 }
3390                 // log_debug("sco rx %u", conn->sco_rx_ms);
3391                 sco_schedule_tx(conn);
3392             }
3393         }
3394     }
3395 #endif
3396 
3397     // deliver to app
3398     if (hci_stack->sco_packet_handler) {
3399         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3400     }
3401 
3402 #ifdef HAVE_SCO_TRANSPORT
3403     // We can send one packet for each received packet
3404     conn->sco_tx_ready++;
3405     hci_notify_if_sco_can_send_now();
3406 #endif
3407 
3408 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3409     conn->num_packets_completed++;
3410     hci_stack->host_completed_packets = 1;
3411     hci_run();
3412 #endif
3413 }
3414 #endif
3415 
3416 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3417     hci_dump_packet(packet_type, 1, packet, size);
3418     switch (packet_type) {
3419         case HCI_EVENT_PACKET:
3420             event_handler(packet, size);
3421             break;
3422         case HCI_ACL_DATA_PACKET:
3423             acl_handler(packet, size);
3424             break;
3425 #ifdef ENABLE_CLASSIC
3426         case HCI_SCO_DATA_PACKET:
3427             sco_handler(packet, size);
3428             break;
3429 #endif
3430         default:
3431             break;
3432     }
3433 }
3434 
3435 /**
3436  * @brief Add event packet handler.
3437  */
3438 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3439     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3440 }
3441 
3442 
3443 /** Register HCI packet handlers */
3444 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3445     hci_stack->acl_packet_handler = handler;
3446 }
3447 
3448 #ifdef ENABLE_CLASSIC
3449 /**
3450  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3451  */
3452 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3453     hci_stack->sco_packet_handler = handler;
3454 }
3455 #endif
3456 
3457 static void hci_state_reset(void){
3458     // no connections yet
3459     hci_stack->connections = NULL;
3460 
3461     // keep discoverable/connectable as this has been requested by the client(s)
3462     // hci_stack->discoverable = 0;
3463     // hci_stack->connectable = 0;
3464     // hci_stack->bondable = 1;
3465     // hci_stack->own_addr_type = 0;
3466 
3467     // buffer is free
3468     hci_stack->hci_packet_buffer_reserved = false;
3469 
3470     // no pending cmds
3471     hci_stack->decline_reason = 0;
3472 
3473     hci_stack->secure_connections_active = false;
3474 
3475 #ifdef ENABLE_CLASSIC
3476     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3477     hci_stack->gap_tasks =
3478             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3479             GAP_TASK_SET_CLASS_OF_DEVICE |
3480             GAP_TASK_SET_LOCAL_NAME |
3481             GAP_TASK_SET_EIR_DATA |
3482             GAP_TASK_WRITE_SCAN_ENABLE;
3483 #endif
3484 
3485 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3486     hci_stack->classic_read_local_oob_data = true;
3487     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3488 #endif
3489 
3490     // LE
3491 #ifdef ENABLE_BLE
3492     memset(hci_stack->le_random_address, 0, 6);
3493     hci_stack->le_random_address_set = 0;
3494 #endif
3495 #ifdef ENABLE_LE_CENTRAL
3496     hci_stack->le_scanning_active  = false;
3497     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3498     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3499     hci_stack->le_whitelist_capacity = 0;
3500 #endif
3501 #ifdef ENABLE_LE_PERIPHERAL
3502     hci_stack->le_advertisements_active = false;
3503     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3504         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3505     }
3506     if (hci_stack->le_advertisements_data != NULL){
3507         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3508     }
3509 #endif
3510 }
3511 
3512 #ifdef ENABLE_CLASSIC
3513 /**
3514  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3515  */
3516 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3517     // store and open remote device db
3518     hci_stack->link_key_db = link_key_db;
3519     if (hci_stack->link_key_db) {
3520         hci_stack->link_key_db->open();
3521     }
3522 }
3523 #endif
3524 
3525 void hci_init(const hci_transport_t *transport, const void *config){
3526 
3527 #ifdef HAVE_MALLOC
3528     if (!hci_stack) {
3529         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3530     }
3531 #else
3532     hci_stack = &hci_stack_static;
3533 #endif
3534     memset(hci_stack, 0, sizeof(hci_stack_t));
3535 
3536     // reference to use transport layer implementation
3537     hci_stack->hci_transport = transport;
3538 
3539     // reference to used config
3540     hci_stack->config = config;
3541 
3542     // setup pointer for outgoing packet buffer
3543     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3544 
3545     // max acl payload size defined in config.h
3546     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3547 
3548     // register packet handlers with transport
3549     transport->register_packet_handler(&packet_handler);
3550 
3551     hci_stack->state = HCI_STATE_OFF;
3552 
3553     // class of device
3554     hci_stack->class_of_device = 0x007a020c; // Smartphone
3555 
3556     // bondable by default
3557     hci_stack->bondable = 1;
3558 
3559 #ifdef ENABLE_CLASSIC
3560     // classic name
3561     hci_stack->local_name = default_classic_name;
3562 
3563     // Master slave policy
3564     hci_stack->master_slave_policy = 1;
3565 
3566     // Allow Role Switch
3567     hci_stack->allow_role_switch = 1;
3568 
3569     // Default / minimum security level = 2
3570     hci_stack->gap_security_level = LEVEL_2;
3571 
3572     // Default Security Mode 4
3573     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3574 
3575     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3576     hci_stack->gap_required_encyrption_key_size = 7;
3577 
3578     // Link Supervision Timeout
3579     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3580 
3581 #endif
3582 
3583     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3584     hci_stack->ssp_enable = 1;
3585     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3586     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3587     hci_stack->ssp_auto_accept = 1;
3588 
3589     // Secure Connections: enable (requires support from Controller)
3590     hci_stack->secure_connections_enable = true;
3591 
3592     // voice setting - signed 16 bit pcm data with CVSD over the air
3593     hci_stack->sco_voice_setting = 0x60;
3594 
3595 #ifdef ENABLE_LE_CENTRAL
3596     // connection parameter to use for outgoing connections
3597     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3598     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3599     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3600     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3601     hci_stack->le_connection_latency      = 4;         // 4
3602     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3603     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3604     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3605 
3606     // default LE Scanning
3607     hci_stack->le_scan_type     =   0x1; // active
3608     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3609     hci_stack->le_scan_window   =  0x30; //  30 ms
3610 #endif
3611 
3612 #ifdef ENABLE_LE_PERIPHERAL
3613     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3614 #endif
3615 
3616     // connection parameter range used to answer connection parameter update requests in l2cap
3617     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3618     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3619     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3620     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3621     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3622     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3623 
3624     hci_state_reset();
3625 }
3626 
3627 void hci_deinit(void){
3628 #ifdef HAVE_MALLOC
3629     if (hci_stack) {
3630         free(hci_stack);
3631     }
3632 #endif
3633     hci_stack = NULL;
3634 
3635 #ifdef ENABLE_CLASSIC
3636     disable_l2cap_timeouts = 0;
3637 #endif
3638 }
3639 
3640 /**
3641  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3642  */
3643 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3644     hci_stack->chipset = chipset_driver;
3645 
3646     // reset chipset driver - init is also called on power_up
3647     if (hci_stack->chipset && hci_stack->chipset->init){
3648         hci_stack->chipset->init(hci_stack->config);
3649     }
3650 }
3651 
3652 /**
3653  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3654  */
3655 void hci_set_control(const btstack_control_t *hardware_control){
3656     // references to used control implementation
3657     hci_stack->control = hardware_control;
3658     // init with transport config
3659     hardware_control->init(hci_stack->config);
3660 }
3661 
3662 void hci_close(void){
3663 
3664 #ifdef ENABLE_CLASSIC
3665     // close remote device db
3666     if (hci_stack->link_key_db) {
3667         hci_stack->link_key_db->close();
3668     }
3669 #endif
3670 
3671     btstack_linked_list_iterator_t lit;
3672     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3673     while (btstack_linked_list_iterator_has_next(&lit)){
3674         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3675         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3676         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3677         hci_shutdown_connection(connection);
3678     }
3679 
3680     hci_power_control(HCI_POWER_OFF);
3681 
3682 #ifdef HAVE_MALLOC
3683     free(hci_stack);
3684 #endif
3685     hci_stack = NULL;
3686 }
3687 
3688 #ifdef HAVE_SCO_TRANSPORT
3689 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3690     hci_stack->sco_transport = sco_transport;
3691     sco_transport->register_packet_handler(&packet_handler);
3692 }
3693 #endif
3694 
3695 #ifdef ENABLE_CLASSIC
3696 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3697     // validate ranage and set
3698     if (encryption_key_size < 7)  return;
3699     if (encryption_key_size > 16) return;
3700     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3701 }
3702 
3703 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3704     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3705         hci_stack->gap_security_mode = security_mode;
3706         return ERROR_CODE_SUCCESS;
3707     } else {
3708         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3709     }
3710 }
3711 
3712 gap_security_mode_t gap_get_security_mode(void){
3713     return hci_stack->gap_security_mode;
3714 }
3715 
3716 void gap_set_security_level(gap_security_level_t security_level){
3717     hci_stack->gap_security_level = security_level;
3718 }
3719 
3720 gap_security_level_t gap_get_security_level(void){
3721     if (hci_stack->gap_secure_connections_only_mode){
3722         return LEVEL_4;
3723     }
3724     return hci_stack->gap_security_level;
3725 }
3726 
3727 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3728     hci_stack->gap_minimal_service_security_level = security_level;
3729 }
3730 
3731 void gap_set_secure_connections_only_mode(bool enable){
3732     hci_stack->gap_secure_connections_only_mode = enable;
3733 }
3734 
3735 bool gap_get_secure_connections_only_mode(void){
3736     return hci_stack->gap_secure_connections_only_mode;
3737 }
3738 #endif
3739 
3740 #ifdef ENABLE_CLASSIC
3741 void gap_set_class_of_device(uint32_t class_of_device){
3742     hci_stack->class_of_device = class_of_device;
3743     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3744     hci_run();
3745 }
3746 
3747 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3748     hci_stack->default_link_policy_settings = default_link_policy_settings;
3749     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3750     hci_run();
3751 }
3752 
3753 void gap_set_allow_role_switch(bool allow_role_switch){
3754     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3755 }
3756 
3757 uint8_t hci_get_allow_role_switch(void){
3758     return  hci_stack->allow_role_switch;
3759 }
3760 
3761 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3762     hci_stack->link_supervision_timeout = link_supervision_timeout;
3763 }
3764 
3765 void hci_disable_l2cap_timeout_check(void){
3766     disable_l2cap_timeouts = 1;
3767 }
3768 #endif
3769 
3770 #ifndef HAVE_HOST_CONTROLLER_API
3771 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3772 void hci_set_bd_addr(bd_addr_t addr){
3773     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3774     hci_stack->custom_bd_addr_set = 1;
3775 }
3776 #endif
3777 
3778 // State-Module-Driver overview
3779 // state                    module  low-level
3780 // HCI_STATE_OFF             off      close
3781 // HCI_STATE_INITIALIZING,   on       open
3782 // HCI_STATE_WORKING,        on       open
3783 // HCI_STATE_HALTING,        on       open
3784 // HCI_STATE_SLEEPING,    off/sleep   close
3785 // HCI_STATE_FALLING_ASLEEP  on       open
3786 
3787 static int hci_power_control_on(void){
3788 
3789     // power on
3790     int err = 0;
3791     if (hci_stack->control && hci_stack->control->on){
3792         err = (*hci_stack->control->on)();
3793     }
3794     if (err){
3795         log_error( "POWER_ON failed");
3796         hci_emit_hci_open_failed();
3797         return err;
3798     }
3799 
3800     // int chipset driver
3801     if (hci_stack->chipset && hci_stack->chipset->init){
3802         hci_stack->chipset->init(hci_stack->config);
3803     }
3804 
3805     // init transport
3806     if (hci_stack->hci_transport->init){
3807         hci_stack->hci_transport->init(hci_stack->config);
3808     }
3809 
3810     // open transport
3811     err = hci_stack->hci_transport->open();
3812     if (err){
3813         log_error( "HCI_INIT failed, turning Bluetooth off again");
3814         if (hci_stack->control && hci_stack->control->off){
3815             (*hci_stack->control->off)();
3816         }
3817         hci_emit_hci_open_failed();
3818         return err;
3819     }
3820     return 0;
3821 }
3822 
3823 static void hci_power_control_off(void){
3824 
3825     log_info("hci_power_control_off");
3826 
3827     // close low-level device
3828     hci_stack->hci_transport->close();
3829 
3830     log_info("hci_power_control_off - hci_transport closed");
3831 
3832     // power off
3833     if (hci_stack->control && hci_stack->control->off){
3834         (*hci_stack->control->off)();
3835     }
3836 
3837     log_info("hci_power_control_off - control closed");
3838 
3839     hci_stack->state = HCI_STATE_OFF;
3840 }
3841 
3842 static void hci_power_control_sleep(void){
3843 
3844     log_info("hci_power_control_sleep");
3845 
3846 #if 0
3847     // don't close serial port during sleep
3848 
3849     // close low-level device
3850     hci_stack->hci_transport->close(hci_stack->config);
3851 #endif
3852 
3853     // sleep mode
3854     if (hci_stack->control && hci_stack->control->sleep){
3855         (*hci_stack->control->sleep)();
3856     }
3857 
3858     hci_stack->state = HCI_STATE_SLEEPING;
3859 }
3860 
3861 static int hci_power_control_wake(void){
3862 
3863     log_info("hci_power_control_wake");
3864 
3865     // wake on
3866     if (hci_stack->control && hci_stack->control->wake){
3867         (*hci_stack->control->wake)();
3868     }
3869 
3870 #if 0
3871     // open low-level device
3872     int err = hci_stack->hci_transport->open(hci_stack->config);
3873     if (err){
3874         log_error( "HCI_INIT failed, turning Bluetooth off again");
3875         if (hci_stack->control && hci_stack->control->off){
3876             (*hci_stack->control->off)();
3877         }
3878         hci_emit_hci_open_failed();
3879         return err;
3880     }
3881 #endif
3882 
3883     return 0;
3884 }
3885 
3886 static void hci_power_transition_to_initializing(void){
3887     // set up state machine
3888     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3889     hci_stack->hci_packet_buffer_reserved = false;
3890     hci_stack->state = HCI_STATE_INITIALIZING;
3891     hci_stack->substate = HCI_INIT_SEND_RESET;
3892 }
3893 
3894 // returns error
3895 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3896     int err;
3897     switch (power_mode){
3898         case HCI_POWER_ON:
3899             err = hci_power_control_on();
3900             if (err != 0) {
3901                 log_error("hci_power_control_on() error %d", err);
3902                 return err;
3903             }
3904             hci_power_transition_to_initializing();
3905             break;
3906         case HCI_POWER_OFF:
3907             // do nothing
3908             break;
3909         case HCI_POWER_SLEEP:
3910             // do nothing (with SLEEP == OFF)
3911             break;
3912         default:
3913             btstack_assert(false);
3914             break;
3915     }
3916     return ERROR_CODE_SUCCESS;
3917 }
3918 
3919 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3920     switch (power_mode){
3921         case HCI_POWER_ON:
3922             // do nothing
3923             break;
3924         case HCI_POWER_OFF:
3925             // no connections yet, just turn it off
3926             hci_power_control_off();
3927             break;
3928         case HCI_POWER_SLEEP:
3929             // no connections yet, just turn it off
3930             hci_power_control_sleep();
3931             break;
3932         default:
3933             btstack_assert(false);
3934             break;
3935     }
3936     return ERROR_CODE_SUCCESS;
3937 }
3938 
3939 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3940     switch (power_mode){
3941         case HCI_POWER_ON:
3942             // do nothing
3943             break;
3944         case HCI_POWER_OFF:
3945             // see hci_run
3946             hci_stack->state = HCI_STATE_HALTING;
3947             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3948             break;
3949         case HCI_POWER_SLEEP:
3950             // see hci_run
3951             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3952             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3953             break;
3954         default:
3955             btstack_assert(false);
3956             break;
3957     }
3958     return ERROR_CODE_SUCCESS;
3959 }
3960 
3961 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3962     switch (power_mode){
3963         case HCI_POWER_ON:
3964             hci_power_transition_to_initializing();
3965             break;
3966         case HCI_POWER_OFF:
3967             // do nothing
3968             break;
3969         case HCI_POWER_SLEEP:
3970             // see hci_run
3971             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3972             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3973             break;
3974         default:
3975             btstack_assert(false);
3976             break;
3977     }
3978     return ERROR_CODE_SUCCESS;
3979 }
3980 
3981 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3982     switch (power_mode){
3983         case HCI_POWER_ON:
3984             hci_power_transition_to_initializing();
3985             break;
3986         case HCI_POWER_OFF:
3987             // see hci_run
3988             hci_stack->state = HCI_STATE_HALTING;
3989             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3990             break;
3991         case HCI_POWER_SLEEP:
3992             // do nothing
3993             break;
3994         default:
3995             btstack_assert(false);
3996             break;
3997     }
3998     return ERROR_CODE_SUCCESS;
3999 }
4000 
4001 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4002     int err;
4003     switch (power_mode){
4004         case HCI_POWER_ON:
4005             err = hci_power_control_wake();
4006             if (err) return err;
4007             hci_power_transition_to_initializing();
4008             break;
4009         case HCI_POWER_OFF:
4010             hci_stack->state = HCI_STATE_HALTING;
4011             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4012             break;
4013         case HCI_POWER_SLEEP:
4014             // do nothing
4015             break;
4016         default:
4017             btstack_assert(false);
4018             break;
4019     }
4020     return ERROR_CODE_SUCCESS;
4021 }
4022 
4023 int hci_power_control(HCI_POWER_MODE power_mode){
4024     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4025     int err = 0;
4026     switch (hci_stack->state){
4027         case HCI_STATE_OFF:
4028             err = hci_power_control_state_off(power_mode);
4029             break;
4030         case HCI_STATE_INITIALIZING:
4031             err = hci_power_control_state_initializing(power_mode);
4032             break;
4033         case HCI_STATE_WORKING:
4034             err = hci_power_control_state_working(power_mode);
4035             break;
4036         case HCI_STATE_HALTING:
4037             err = hci_power_control_state_halting(power_mode);
4038             break;
4039         case HCI_STATE_FALLING_ASLEEP:
4040             err = hci_power_control_state_falling_asleep(power_mode);
4041             break;
4042         case HCI_STATE_SLEEPING:
4043             err = hci_power_control_state_sleeping(power_mode);
4044             break;
4045         default:
4046             btstack_assert(false);
4047             break;
4048     }
4049     if (err != 0){
4050         return err;
4051     }
4052 
4053     // create internal event
4054 	hci_emit_state();
4055 
4056 	// trigger next/first action
4057 	hci_run();
4058 
4059     return 0;
4060 }
4061 
4062 
4063 #ifdef ENABLE_CLASSIC
4064 
4065 static void hci_update_scan_enable(void){
4066     // 2 = page scan, 1 = inq scan
4067     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4068     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4069     hci_run();
4070 }
4071 
4072 void gap_discoverable_control(uint8_t enable){
4073     if (enable) enable = 1; // normalize argument
4074 
4075     if (hci_stack->discoverable == enable){
4076         hci_emit_discoverable_enabled(hci_stack->discoverable);
4077         return;
4078     }
4079 
4080     hci_stack->discoverable = enable;
4081     hci_update_scan_enable();
4082 }
4083 
4084 void gap_connectable_control(uint8_t enable){
4085     if (enable) enable = 1; // normalize argument
4086 
4087     // don't emit event
4088     if (hci_stack->connectable == enable) return;
4089 
4090     hci_stack->connectable = enable;
4091     hci_update_scan_enable();
4092 }
4093 #endif
4094 
4095 void gap_local_bd_addr(bd_addr_t address_buffer){
4096     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4097 }
4098 
4099 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4100 static void hci_host_num_completed_packets(void){
4101 
4102     // create packet manually as arrays are not supported and num_commands should not get reduced
4103     hci_reserve_packet_buffer();
4104     uint8_t * packet = hci_get_outgoing_packet_buffer();
4105 
4106     uint16_t size = 0;
4107     uint16_t num_handles = 0;
4108     packet[size++] = 0x35;
4109     packet[size++] = 0x0c;
4110     size++;  // skip param len
4111     size++;  // skip num handles
4112 
4113     // add { handle, packets } entries
4114     btstack_linked_item_t * it;
4115     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4116         hci_connection_t * connection = (hci_connection_t *) it;
4117         if (connection->num_packets_completed){
4118             little_endian_store_16(packet, size, connection->con_handle);
4119             size += 2;
4120             little_endian_store_16(packet, size, connection->num_packets_completed);
4121             size += 2;
4122             //
4123             num_handles++;
4124             connection->num_packets_completed = 0;
4125         }
4126     }
4127 
4128     packet[2] = size - 3;
4129     packet[3] = num_handles;
4130 
4131     hci_stack->host_completed_packets = 0;
4132 
4133     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4134     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4135 
4136     // release packet buffer for synchronous transport implementations
4137     if (hci_transport_synchronous()){
4138         hci_release_packet_buffer();
4139         hci_emit_transport_packet_sent();
4140     }
4141 }
4142 #endif
4143 
4144 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4145     UNUSED(ds);
4146     hci_stack->substate = HCI_HALTING_CLOSE;
4147     // allow packet handlers to defer final shutdown
4148     hci_emit_state();
4149     hci_run();
4150 }
4151 
4152 static bool hci_run_acl_fragments(void){
4153     if (hci_stack->acl_fragmentation_total_size > 0u) {
4154         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4155         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4156         if (connection) {
4157             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4158                 hci_send_acl_packet_fragments(connection);
4159                 return true;
4160             }
4161         } else {
4162             // connection gone -> discard further fragments
4163             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4164             hci_stack->acl_fragmentation_total_size = 0;
4165             hci_stack->acl_fragmentation_pos = 0;
4166         }
4167     }
4168     return false;
4169 }
4170 
4171 #ifdef ENABLE_CLASSIC
4172 static bool hci_run_general_gap_classic(void){
4173 
4174     // assert stack is working and classic is active
4175     if (hci_classic_supported() == false)      return false;
4176     if (hci_stack->state != HCI_STATE_WORKING) return false;
4177 
4178     // decline incoming connections
4179     if (hci_stack->decline_reason){
4180         uint8_t reason = hci_stack->decline_reason;
4181         hci_stack->decline_reason = 0;
4182         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4183         return true;
4184     }
4185 
4186     if (hci_stack->gap_tasks != 0){
4187         hci_run_gap_tasks_classic();
4188         return true;
4189     }
4190 
4191     // start/stop inquiry
4192     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4193         uint8_t duration = hci_stack->inquiry_state;
4194         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4195         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4196         return true;
4197     }
4198     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4199         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4200         hci_send_cmd(&hci_inquiry_cancel);
4201         return true;
4202     }
4203     // remote name request
4204     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4205         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4206         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4207                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4208         return true;
4209     }
4210 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4211     // Local OOB data
4212     if (hci_stack->classic_read_local_oob_data){
4213         hci_stack->classic_read_local_oob_data = false;
4214         if (hci_stack->local_supported_commands[1] & 0x10u){
4215             hci_send_cmd(&hci_read_local_extended_oob_data);
4216         } else {
4217             hci_send_cmd(&hci_read_local_oob_data);
4218         }
4219     }
4220 #endif
4221     // pairing
4222     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4223         uint8_t state = hci_stack->gap_pairing_state;
4224         uint8_t pin_code[16];
4225         switch (state){
4226             case GAP_PAIRING_STATE_SEND_PIN:
4227                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4228                 memset(pin_code, 0, 16);
4229                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4230                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4231                 break;
4232             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4233                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4234                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4235                 break;
4236             case GAP_PAIRING_STATE_SEND_PASSKEY:
4237                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4238                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4239                 break;
4240             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4241                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4242                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4243                 break;
4244             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4245                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4246                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4247                 break;
4248             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4249                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4250                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4251                 break;
4252             default:
4253                 break;
4254         }
4255         return true;
4256     }
4257     return false;
4258 }
4259 #endif
4260 
4261 #ifdef ENABLE_BLE
4262 static bool hci_run_general_gap_le(void){
4263 
4264     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4265 
4266     if (hci_stack->state != HCI_STATE_WORKING) return false;
4267     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4268 
4269 
4270     // Phase 1: collect what to stop
4271 
4272     bool scanning_stop = false;
4273     bool connecting_stop = false;
4274     bool advertising_stop = false;
4275 
4276 #ifndef ENABLE_LE_CENTRAL
4277     UNUSED(scanning_stop);
4278     UNUSED(connecting_stop);
4279 #endif
4280 #ifndef ENABLE_LE_PERIPHERAL
4281     UNUSED(advertising_stop);
4282 #endif
4283 
4284     // check if whitelist needs modification
4285     bool whitelist_modification_pending = false;
4286     btstack_linked_list_iterator_t lit;
4287     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4288     while (btstack_linked_list_iterator_has_next(&lit)){
4289         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4290         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4291             whitelist_modification_pending = true;
4292             break;
4293         }
4294     }
4295     // check if resolving list needs modification
4296     bool resolving_list_modification_pending = false;
4297 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4298     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4299 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4300         resolving_list_modification_pending = true;
4301     }
4302 #endif
4303 
4304 #ifdef ENABLE_LE_CENTRAL
4305     // scanning control
4306     if (hci_stack->le_scanning_active) {
4307         // stop if:
4308         // - parameter change required
4309         // - it's disabled
4310         // - whitelist change required but used for scanning
4311         // - resolving list modified
4312         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4313         if ((hci_stack->le_scanning_param_update) ||
4314             !hci_stack->le_scanning_enabled ||
4315             scanning_uses_whitelist ||
4316             resolving_list_modification_pending){
4317 
4318             scanning_stop = true;
4319         }
4320     }
4321 #endif
4322 
4323 #ifdef ENABLE_LE_CENTRAL
4324     // connecting control
4325     bool connecting_with_whitelist;
4326     switch (hci_stack->le_connecting_state){
4327         case LE_CONNECTING_DIRECT:
4328         case LE_CONNECTING_WHITELIST:
4329             // stop connecting if:
4330             // - connecting uses white and whitelist modification pending
4331             // - if it got disabled
4332             // - resolving list modified
4333             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4334             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4335                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4336                 resolving_list_modification_pending) {
4337 
4338                 connecting_stop = true;
4339             }
4340             break;
4341         default:
4342             break;
4343     }
4344 #endif
4345 
4346 #ifdef ENABLE_LE_PERIPHERAL
4347     // le advertisement control
4348     if (hci_stack->le_advertisements_active){
4349         // stop if:
4350         // - parameter change required
4351         // - it's disabled
4352         // - whitelist change required but used for advertisement filter policy
4353         // - resolving list modified
4354         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4355         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4356         if (advertising_change ||
4357             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4358             (advertising_uses_whitelist & whitelist_modification_pending) ||
4359             resolving_list_modification_pending) {
4360 
4361             advertising_stop = true;
4362         }
4363     }
4364 #endif
4365 
4366 
4367     // Phase 2: stop everything that should be off during modifications
4368 
4369 #ifdef ENABLE_LE_CENTRAL
4370     if (scanning_stop){
4371         hci_stack->le_scanning_active = false;
4372         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4373         return true;
4374     }
4375 #endif
4376 
4377 #ifdef ENABLE_LE_CENTRAL
4378     if (connecting_stop){
4379         hci_send_cmd(&hci_le_create_connection_cancel);
4380         return true;
4381     }
4382 #endif
4383 
4384 #ifdef ENABLE_LE_PERIPHERAL
4385     if (advertising_stop){
4386         hci_stack->le_advertisements_active = false;
4387         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4388         return true;
4389     }
4390 #endif
4391 
4392     // Phase 3: modify
4393 
4394 #ifdef ENABLE_LE_CENTRAL
4395     if (hci_stack->le_scanning_param_update){
4396         hci_stack->le_scanning_param_update = false;
4397         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4398                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4399         return true;
4400     }
4401 #endif
4402 
4403 #ifdef ENABLE_LE_PERIPHERAL
4404     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4405         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4406         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4407         hci_send_cmd(&hci_le_set_advertising_parameters,
4408                      hci_stack->le_advertisements_interval_min,
4409                      hci_stack->le_advertisements_interval_max,
4410                      hci_stack->le_advertisements_type,
4411                      hci_stack->le_advertisements_own_addr_type,
4412                      hci_stack->le_advertisements_direct_address_type,
4413                      hci_stack->le_advertisements_direct_address,
4414                      hci_stack->le_advertisements_channel_map,
4415                      hci_stack->le_advertisements_filter_policy);
4416         return true;
4417     }
4418     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4419         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4420         uint8_t adv_data_clean[31];
4421         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4422         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4423                      hci_stack->le_advertisements_data_len);
4424         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4425         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4426         return true;
4427     }
4428     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4429         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4430         uint8_t scan_data_clean[31];
4431         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4432         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4433                      hci_stack->le_scan_response_data_len);
4434         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4435         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4436         return true;
4437     }
4438 #endif
4439 
4440 
4441 #ifdef ENABLE_LE_CENTRAL
4442     // if connect with whitelist was active and is not cancelled yet, wait until next time
4443     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4444 #endif
4445 
4446     // LE Whitelist Management
4447     if (whitelist_modification_pending){
4448         // add/remove entries
4449         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4450         while (btstack_linked_list_iterator_has_next(&lit)){
4451             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4452 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4453 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4454 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4455 				return true;
4456 			}
4457             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4458 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4459                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4460                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4461                 return true;
4462             }
4463             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4464 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4465 				btstack_memory_whitelist_entry_free(entry);
4466             }
4467         }
4468     }
4469 
4470 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4471     // LE Resolving List Management
4472     if (resolving_list_supported) {
4473 		uint16_t i;
4474 		switch (hci_stack->le_resolving_list_state) {
4475 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4476 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4477 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4478 				return true;
4479 			case LE_RESOLVING_LIST_READ_SIZE:
4480 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4481 				hci_send_cmd(&hci_le_read_resolving_list_size);
4482 				return true;
4483 			case LE_RESOLVING_LIST_SEND_CLEAR:
4484 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4485 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4486 							  sizeof(hci_stack->le_resolving_list_add_entries));
4487 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4488 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4489 				hci_send_cmd(&hci_le_clear_resolving_list);
4490 				return true;
4491 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4492 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4493 					uint8_t offset = i >> 3;
4494 					uint8_t mask = 1 << (i & 7);
4495 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4496 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4497 					bd_addr_t peer_identity_addreses;
4498 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4499 					sm_key_t peer_irk;
4500 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4501 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4502 
4503 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4504 					// trigger whitelist entry 'update' (work around for controller bug)
4505 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4506 					while (btstack_linked_list_iterator_has_next(&lit)) {
4507 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4508 						if (entry->address_type != peer_identity_addr_type) continue;
4509 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4510 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4511 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4512 					}
4513 #endif
4514 
4515 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4516 								 peer_identity_addreses);
4517 					return true;
4518 				}
4519 
4520 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4521 
4522 				/* fall through */
4523 
4524 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4525 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4526 					uint8_t offset = i >> 3;
4527 					uint8_t mask = 1 << (i & 7);
4528 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4529 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4530 					bd_addr_t peer_identity_addreses;
4531 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4532 					sm_key_t peer_irk;
4533 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4534 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4535 					const uint8_t *local_irk = gap_get_persistent_irk();
4536 					// command uses format specifier 'P' that stores 16-byte value without flip
4537 					uint8_t local_irk_flipped[16];
4538 					uint8_t peer_irk_flipped[16];
4539 					reverse_128(local_irk, local_irk_flipped);
4540 					reverse_128(peer_irk, peer_irk_flipped);
4541 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4542 								 peer_irk_flipped, local_irk_flipped);
4543 					return true;
4544 				}
4545 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4546 				break;
4547 
4548 			default:
4549 				break;
4550 		}
4551 	}
4552     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4553 #endif
4554 
4555     // Phase 4: restore state
4556 
4557 #ifdef ENABLE_LE_CENTRAL
4558     // re-start scanning
4559     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4560         hci_stack->le_scanning_active = true;
4561         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4562         return true;
4563     }
4564 #endif
4565 
4566 #ifdef ENABLE_LE_CENTRAL
4567     // re-start connecting
4568     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4569         bd_addr_t null_addr;
4570         memset(null_addr, 0, 6);
4571         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4572         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4573         hci_send_cmd(&hci_le_create_connection,
4574                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4575                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4576                      1,         // use whitelist
4577                      0,         // peer address type
4578                      null_addr, // peer bd addr
4579                      hci_stack->le_connection_own_addr_type,   // our addr type:
4580                      hci_stack->le_connection_interval_min,    // conn interval min
4581                      hci_stack->le_connection_interval_max,    // conn interval max
4582                      hci_stack->le_connection_latency,         // conn latency
4583                      hci_stack->le_supervision_timeout,        // conn latency
4584                      hci_stack->le_minimum_ce_length,          // min ce length
4585                      hci_stack->le_maximum_ce_length           // max ce length
4586         );
4587         return true;
4588     }
4589 #endif
4590 
4591 #ifdef ENABLE_LE_PERIPHERAL
4592     // re-start advertising
4593     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4594         // check if advertisements should be enabled given
4595         hci_stack->le_advertisements_active = true;
4596         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4597         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4598         return true;
4599     }
4600 #endif
4601 
4602     return false;
4603 }
4604 #endif
4605 
4606 static bool hci_run_general_pending_commands(void){
4607     btstack_linked_item_t * it;
4608     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4609         hci_connection_t * connection = (hci_connection_t *) it;
4610 
4611         switch(connection->state){
4612             case SEND_CREATE_CONNECTION:
4613                 switch(connection->address_type){
4614 #ifdef ENABLE_CLASSIC
4615                     case BD_ADDR_TYPE_ACL:
4616                         log_info("sending hci_create_connection");
4617                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4618                         break;
4619 #endif
4620                     default:
4621 #ifdef ENABLE_BLE
4622 #ifdef ENABLE_LE_CENTRAL
4623                         log_info("sending hci_le_create_connection");
4624                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4625                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4626                         hci_send_cmd(&hci_le_create_connection,
4627                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4628                                      hci_stack->le_connection_scan_window,      // conn scan windows
4629                                      0,         // don't use whitelist
4630                                      connection->address_type, // peer address type
4631                                      connection->address,      // peer bd addr
4632                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4633                                      hci_stack->le_connection_interval_min,    // conn interval min
4634                                      hci_stack->le_connection_interval_max,    // conn interval max
4635                                      hci_stack->le_connection_latency,         // conn latency
4636                                      hci_stack->le_supervision_timeout,        // conn latency
4637                                      hci_stack->le_minimum_ce_length,          // min ce length
4638                                      hci_stack->le_maximum_ce_length          // max ce length
4639                         );
4640                         connection->state = SENT_CREATE_CONNECTION;
4641 #endif
4642 #endif
4643                         break;
4644                 }
4645                 return true;
4646 
4647 #ifdef ENABLE_CLASSIC
4648             case RECEIVED_CONNECTION_REQUEST:
4649                 connection->role  = HCI_ROLE_SLAVE;
4650                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4651                     log_info("sending hci_accept_connection_request");
4652                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4653                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4654                 }
4655                 return true;
4656 #endif
4657 
4658 #ifdef ENABLE_BLE
4659 #ifdef ENABLE_LE_CENTRAL
4660             case SEND_CANCEL_CONNECTION:
4661                 connection->state = SENT_CANCEL_CONNECTION;
4662                 hci_send_cmd(&hci_le_create_connection_cancel);
4663                 return true;
4664 #endif
4665 #endif
4666             case SEND_DISCONNECT:
4667                 connection->state = SENT_DISCONNECT;
4668                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4669                 return true;
4670 
4671             default:
4672                 break;
4673         }
4674 
4675         // no further commands if connection is about to get shut down
4676         if (connection->state == SENT_DISCONNECT) continue;
4677 
4678         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4679             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4680             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4681             return true;
4682         }
4683 
4684 #ifdef ENABLE_CLASSIC
4685 
4686         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4687             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4688             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4689             return true;
4690         }
4691 
4692         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4693             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4694             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4695             return true;
4696         }
4697 
4698         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4699             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4700             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4701             return true;
4702         }
4703 
4704         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4705             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4706             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4707             return true;
4708         }
4709 
4710         // Handling link key request requires remote supported features
4711         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4712             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4713             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4714 
4715             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4716             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4717             if (have_link_key && security_level_sufficient){
4718                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4719             } else {
4720                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4721             }
4722             return true;
4723         }
4724 
4725         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4726             log_info("denying to pin request");
4727             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4728             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4729             return true;
4730         }
4731 
4732         // security assessment requires remote features
4733         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4734             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4735             hci_ssp_assess_security_on_io_cap_request(connection);
4736             // no return here as hci_ssp_assess_security_on_io_cap_request only sets AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY or AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY
4737         }
4738 
4739         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4740             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4741             // set authentication requirements:
4742             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4743             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4744             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4745             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4746                 authreq |= 1;
4747             }
4748             bool bonding = hci_stack->bondable;
4749             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4750                 // if we have received IO Cap Response, we're in responder role
4751                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4752                 if (bonding && !remote_bonding){
4753                     log_info("Remote not bonding, dropping local flag");
4754                     bonding = false;
4755                 }
4756             }
4757             if (bonding){
4758                 if (connection->bonding_flags & BONDING_DEDICATED){
4759                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4760                 } else {
4761                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4762                 }
4763             }
4764             uint8_t have_oob_data = 0;
4765 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4766             if (connection->classic_oob_c_192 != NULL){
4767                     have_oob_data |= 1;
4768             }
4769             if (connection->classic_oob_c_256 != NULL){
4770                 have_oob_data |= 2;
4771             }
4772 #endif
4773             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4774             return true;
4775         }
4776 
4777         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4778             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4779             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4780             return true;
4781         }
4782 
4783 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4784         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4785             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4786             const uint8_t zero[16] = { 0 };
4787             const uint8_t * r_192 = zero;
4788             const uint8_t * c_192 = zero;
4789             const uint8_t * r_256 = zero;
4790             const uint8_t * c_256 = zero;
4791             // verify P-256 OOB
4792             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4793                 c_256 = connection->classic_oob_c_256;
4794                 if (connection->classic_oob_r_256 != NULL) {
4795                     r_256 = connection->classic_oob_r_256;
4796                 }
4797             }
4798             // verify P-192 OOB
4799             if ((connection->classic_oob_c_192 != NULL)) {
4800                 c_192 = connection->classic_oob_c_192;
4801                 if (connection->classic_oob_r_192 != NULL) {
4802                     r_192 = connection->classic_oob_r_192;
4803                 }
4804             }
4805 
4806             // assess security
4807             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4808             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4809             if (need_level_4 && !can_reach_level_4){
4810                 log_info("Level 4 required, but not possible -> abort");
4811                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4812                 // send oob negative reply
4813                 c_256 = NULL;
4814                 c_192 = NULL;
4815             }
4816 
4817             // Reply
4818             if (c_256 != zero) {
4819                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4820             } else if (c_192 != zero){
4821                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4822             } else {
4823                 hci_stack->classic_oob_con_handle = connection->con_handle;
4824                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4825             }
4826             return true;
4827         }
4828 #endif
4829 
4830         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4831             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4832             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4833             return true;
4834         }
4835 
4836         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4837             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4838             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4839             return true;
4840         }
4841 
4842         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4843             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4844             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4845             return true;
4846         }
4847 
4848         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4849             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4850             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4851             connection->state = SENT_DISCONNECT;
4852             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4853             return true;
4854         }
4855 
4856         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4857             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4858             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4859             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4860             return true;
4861         }
4862 
4863         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4864             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4865             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4866             return true;
4867         }
4868         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4869             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4870             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4871             return true;
4872         }
4873 #endif
4874 
4875         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4876             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4877 #ifdef ENABLE_CLASSIC
4878             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4879 #endif
4880             if (connection->state != SENT_DISCONNECT){
4881                 connection->state = SENT_DISCONNECT;
4882                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4883                 return true;
4884             }
4885         }
4886 
4887 #ifdef ENABLE_CLASSIC
4888         uint16_t sniff_min_interval;
4889         switch (connection->sniff_min_interval){
4890             case 0:
4891                 break;
4892             case 0xffff:
4893                 connection->sniff_min_interval = 0;
4894                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4895                 return true;
4896             default:
4897                 sniff_min_interval = connection->sniff_min_interval;
4898                 connection->sniff_min_interval = 0;
4899                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4900                 return true;
4901         }
4902 
4903         if (connection->sniff_subrating_max_latency != 0xffff){
4904             uint16_t max_latency = connection->sniff_subrating_max_latency;
4905             connection->sniff_subrating_max_latency = 0;
4906             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4907             return true;
4908         }
4909 
4910         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4911             uint8_t service_type = (uint8_t) connection->qos_service_type;
4912             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4913             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);
4914             return true;
4915         }
4916 
4917         if (connection->request_role != HCI_ROLE_INVALID){
4918             hci_role_t role = connection->request_role;
4919             connection->request_role = HCI_ROLE_INVALID;
4920             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4921             return true;
4922         }
4923 #endif
4924 
4925 #ifdef ENABLE_BLE
4926         switch (connection->le_con_parameter_update_state){
4927             // response to L2CAP CON PARAMETER UPDATE REQUEST
4928             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4929                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4930                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4931                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4932                              0x0000, 0xffff);
4933                 return true;
4934             case CON_PARAMETER_UPDATE_REPLY:
4935                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4936                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4937                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4938                              0x0000, 0xffff);
4939                 return true;
4940             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4941                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4942                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4943                 return true;
4944             default:
4945                 break;
4946         }
4947         if (connection->le_phy_update_all_phys != 0xffu){
4948             uint8_t all_phys = connection->le_phy_update_all_phys;
4949             connection->le_phy_update_all_phys = 0xff;
4950             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);
4951             return true;
4952         }
4953 #endif
4954     }
4955     return false;
4956 }
4957 
4958 static void hci_run(void){
4959 
4960     bool done;
4961 
4962     // send continuation fragments first, as they block the prepared packet buffer
4963     done = hci_run_acl_fragments();
4964     if (done) return;
4965 
4966 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4967     // send host num completed packets next as they don't require num_cmd_packets > 0
4968     if (!hci_can_send_comand_packet_transport()) return;
4969     if (hci_stack->host_completed_packets){
4970         hci_host_num_completed_packets();
4971         return;
4972     }
4973 #endif
4974 
4975     if (!hci_can_send_command_packet_now()) return;
4976 
4977     // global/non-connection oriented commands
4978 
4979 
4980 #ifdef ENABLE_CLASSIC
4981     // general gap classic
4982     done = hci_run_general_gap_classic();
4983     if (done) return;
4984 #endif
4985 
4986 #ifdef ENABLE_BLE
4987     // general gap le
4988     done = hci_run_general_gap_le();
4989     if (done) return;
4990 #endif
4991 
4992     // send pending HCI commands
4993     done = hci_run_general_pending_commands();
4994     if (done) return;
4995 
4996     // stack state sub statemachines
4997     hci_connection_t * connection;
4998     switch (hci_stack->state){
4999         case HCI_STATE_INITIALIZING:
5000             hci_initializing_run();
5001             break;
5002 
5003         case HCI_STATE_HALTING:
5004 
5005             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5006             switch (hci_stack->substate){
5007                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5008                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5009 
5010 #ifdef ENABLE_BLE
5011 #ifdef ENABLE_LE_CENTRAL
5012                     // free whitelist entries
5013                     {
5014                         btstack_linked_list_iterator_t lit;
5015                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5016                         while (btstack_linked_list_iterator_has_next(&lit)){
5017                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5018                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5019                             btstack_memory_whitelist_entry_free(entry);
5020                         }
5021                     }
5022 #endif
5023 #endif
5024                     // close all open connections
5025                     connection =  (hci_connection_t *) hci_stack->connections;
5026                     if (connection){
5027                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5028                         if (!hci_can_send_command_packet_now()) return;
5029 
5030                         // check state
5031                         if (connection->state == SENT_DISCONNECT) return;
5032                         connection->state = SENT_DISCONNECT;
5033 
5034                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5035 
5036                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5037                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5038 
5039                         // ... which would be ignored anyway as we shutdown (free) the connection now
5040                         hci_shutdown_connection(connection);
5041 
5042                         // finally, send the disconnect command
5043                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5044                         return;
5045                     }
5046 
5047                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5048                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5049                         log_info("HCI_STATE_HALTING: wait 50 ms");
5050                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5051                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5052                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5053                         btstack_run_loop_add_timer(&hci_stack->timeout);
5054                         break;
5055                     }
5056 
5057                     /* fall through */
5058 
5059                 case HCI_HALTING_CLOSE:
5060                     log_info("HCI_STATE_HALTING, calling off");
5061 
5062                     // switch mode
5063                     hci_power_control_off();
5064 
5065                     log_info("HCI_STATE_HALTING, emitting state");
5066                     hci_emit_state();
5067                     log_info("HCI_STATE_HALTING, done");
5068                     break;
5069 
5070                 case HCI_HALTING_W4_TIMER:
5071                     // keep waiting
5072 
5073                     break;
5074                 default:
5075                     break;
5076             }
5077 
5078             break;
5079 
5080         case HCI_STATE_FALLING_ASLEEP:
5081             switch(hci_stack->substate) {
5082                 case HCI_FALLING_ASLEEP_DISCONNECT:
5083                     log_info("HCI_STATE_FALLING_ASLEEP");
5084                     // close all open connections
5085                     connection =  (hci_connection_t *) hci_stack->connections;
5086                     if (connection){
5087 
5088                         // send disconnect
5089                         if (!hci_can_send_command_packet_now()) return;
5090 
5091                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5092                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5093 
5094                         // send disconnected event right away - causes higher layer connections to get closed, too.
5095                         hci_shutdown_connection(connection);
5096                         return;
5097                     }
5098 
5099                     if (hci_classic_supported()){
5100                         // disable page and inquiry scan
5101                         if (!hci_can_send_command_packet_now()) return;
5102 
5103                         log_info("HCI_STATE_HALTING, disabling inq scans");
5104                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5105 
5106                         // continue in next sub state
5107                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5108                         break;
5109                     }
5110 
5111                     /* fall through */
5112 
5113                 case HCI_FALLING_ASLEEP_COMPLETE:
5114                     log_info("HCI_STATE_HALTING, calling sleep");
5115                     // switch mode
5116                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5117                     hci_emit_state();
5118                     break;
5119 
5120                 default:
5121                     break;
5122             }
5123             break;
5124 
5125         default:
5126             break;
5127     }
5128 }
5129 
5130 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5131     // house-keeping
5132 
5133 #ifdef ENABLE_CLASSIC
5134     bd_addr_t addr;
5135     hci_connection_t * conn;
5136 #endif
5137 #ifdef ENABLE_LE_CENTRAL
5138     uint8_t initiator_filter_policy;
5139 #endif
5140 
5141     uint16_t opcode = little_endian_read_16(packet, 0);
5142     switch (opcode) {
5143         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5144             hci_stack->loopback_mode = packet[3];
5145             break;
5146 
5147 #ifdef ENABLE_CLASSIC
5148         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5149             reverse_bd_addr(&packet[3], addr);
5150             log_info("Create_connection to %s", bd_addr_to_str(addr));
5151 
5152             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5153             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5154                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5155                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5156             }
5157 
5158             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5159             if (!conn) {
5160                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5161                 if (!conn) {
5162                     // notify client that alloc failed
5163                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5164                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5165                 }
5166                 conn->state = SEND_CREATE_CONNECTION;
5167                 conn->role  = HCI_ROLE_MASTER;
5168             }
5169 
5170             conn->con_handle = HCI_CON_HANDLE_INVALID;
5171             conn->role = HCI_ROLE_INVALID;
5172 
5173             log_info("conn state %u", conn->state);
5174             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5175             switch (conn->state) {
5176                 // if connection active exists
5177                 case OPEN:
5178                     // and OPEN, emit connection complete command
5179                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5180                     // packet not sent to controller
5181                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5182                 case RECEIVED_DISCONNECTION_COMPLETE:
5183                     // create connection triggered in disconnect complete event, let's do it now
5184                     break;
5185                 case SEND_CREATE_CONNECTION:
5186                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5187                     break;
5188                 default:
5189                     // otherwise, just ignore as it is already in the open process
5190                     // packet not sent to controller
5191                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5192             }
5193             conn->state = SENT_CREATE_CONNECTION;
5194 
5195             // track outgoing connection
5196             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5197             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5198             break;
5199         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5200             if (hci_stack->link_key_db) {
5201                 reverse_bd_addr(&packet[3], addr);
5202                 hci_stack->link_key_db->delete_link_key(addr);
5203             }
5204             break;
5205 
5206 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5207         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5208             // setup_synchronous_connection? Voice setting at offset 22
5209             // TODO: compare to current setting if sco connection already active
5210             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5211             break;
5212         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5213             // accept_synchronus_connection? Voice setting at offset 18
5214             // TODO: compare to current setting if sco connection already active
5215             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5216             break;
5217 #endif
5218 #endif
5219 
5220 #ifdef ENABLE_BLE
5221         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5222             hci_stack->le_random_address_set = 1;
5223             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5224             break;
5225 #ifdef ENABLE_LE_PERIPHERAL
5226         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5227             hci_stack->le_advertisements_active = packet[3] != 0;
5228             break;
5229 #endif
5230 #ifdef ENABLE_LE_CENTRAL
5231         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5232             // white list used?
5233             initiator_filter_policy = packet[7];
5234             switch (initiator_filter_policy) {
5235                 case 0:
5236                     // whitelist not used
5237                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5238                     break;
5239                 case 1:
5240                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5241                     break;
5242                 default:
5243                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5244                     break;
5245             }
5246             // track outgoing connection
5247             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5248             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5249             break;
5250         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5251             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5252             break;
5253 #endif
5254 #endif
5255         default:
5256             break;
5257     }
5258 
5259     hci_stack->num_cmd_packets--;
5260 
5261     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5262     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5263     if (err != 0){
5264         return ERROR_CODE_HARDWARE_FAILURE;
5265     }
5266     return ERROR_CODE_SUCCESS;
5267 }
5268 
5269 // disconnect because of security block
5270 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5271     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5272     if (!connection) return;
5273     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5274 }
5275 
5276 
5277 // Configure Secure Simple Pairing
5278 
5279 #ifdef ENABLE_CLASSIC
5280 
5281 // enable will enable SSP during init
5282 void gap_ssp_set_enable(int enable){
5283     hci_stack->ssp_enable = enable;
5284 }
5285 
5286 static int hci_local_ssp_activated(void){
5287     return gap_ssp_supported() && hci_stack->ssp_enable;
5288 }
5289 
5290 // if set, BTstack will respond to io capability request using authentication requirement
5291 void gap_ssp_set_io_capability(int io_capability){
5292     hci_stack->ssp_io_capability = io_capability;
5293 }
5294 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5295     hci_stack->ssp_authentication_requirement = authentication_requirement;
5296 }
5297 
5298 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5299 void gap_ssp_set_auto_accept(int auto_accept){
5300     hci_stack->ssp_auto_accept = auto_accept;
5301 }
5302 
5303 void gap_secure_connections_enable(bool enable){
5304     hci_stack->secure_connections_enable = enable;
5305 }
5306 
5307 #endif
5308 
5309 // va_list part of hci_send_cmd
5310 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5311     if (!hci_can_send_command_packet_now()){
5312         log_error("hci_send_cmd called but cannot send packet now");
5313         return ERROR_CODE_COMMAND_DISALLOWED;
5314     }
5315 
5316     // for HCI INITIALIZATION
5317     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5318     hci_stack->last_cmd_opcode = cmd->opcode;
5319 
5320     hci_reserve_packet_buffer();
5321     uint8_t * packet = hci_stack->hci_packet_buffer;
5322     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5323     uint8_t status = hci_send_cmd_packet(packet, size);
5324 
5325     // release packet buffer on error or for synchronous transport implementations
5326     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5327         hci_release_packet_buffer();
5328         hci_emit_transport_packet_sent();
5329     }
5330 
5331     return status;
5332 }
5333 
5334 /**
5335  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5336  */
5337 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5338     va_list argptr;
5339     va_start(argptr, cmd);
5340     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5341     va_end(argptr);
5342     return status;
5343 }
5344 
5345 // Create various non-HCI events.
5346 // TODO: generalize, use table similar to hci_create_command
5347 
5348 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5349     // dump packet
5350     if (dump) {
5351         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5352     }
5353 
5354     // dispatch to all event handlers
5355     btstack_linked_list_iterator_t it;
5356     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5357     while (btstack_linked_list_iterator_has_next(&it)){
5358         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5359         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5360     }
5361 }
5362 
5363 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5364     if (!hci_stack->acl_packet_handler) return;
5365     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5366 }
5367 
5368 #ifdef ENABLE_CLASSIC
5369 static void hci_notify_if_sco_can_send_now(void){
5370     // notify SCO sender if waiting
5371     if (!hci_stack->sco_waiting_for_can_send_now) return;
5372     if (hci_can_send_sco_packet_now()){
5373         hci_stack->sco_waiting_for_can_send_now = 0;
5374         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5375         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5376         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5377     }
5378 }
5379 
5380 // parsing end emitting has been merged to reduce code size
5381 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5382     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5383 
5384     uint8_t * eir_data;
5385     ad_context_t context;
5386     const uint8_t * name;
5387     uint8_t         name_len;
5388 
5389     if (size < 3) return;
5390 
5391     int event_type = hci_event_packet_get_type(packet);
5392     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5393     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5394 
5395     switch (event_type){
5396         case HCI_EVENT_INQUIRY_RESULT:
5397         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5398             if (size != (3 + (num_responses * 14))) return;
5399             break;
5400         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5401             if (size != 257) return;
5402             if (num_responses != 1) return;
5403             break;
5404         default:
5405             return;
5406     }
5407 
5408     // event[1] is set at the end
5409     int i;
5410     for (i=0; i<num_responses;i++){
5411         memset(event, 0, sizeof(event));
5412         event[0] = GAP_EVENT_INQUIRY_RESULT;
5413         uint8_t event_size = 27;    // if name is not set by EIR
5414 
5415         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5416         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5417         (void)memcpy(&event[9],
5418                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5419                      3); // class of device
5420         (void)memcpy(&event[12],
5421                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5422                      2); // clock offset
5423 
5424         switch (event_type){
5425             case HCI_EVENT_INQUIRY_RESULT:
5426                 // 14,15,16,17 = 0, size 18
5427                 break;
5428             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5429                 event[14] = 1;
5430                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5431                 // 16,17 = 0, size 18
5432                 break;
5433             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5434                 event[14] = 1;
5435                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5436                 // EIR packets only contain a single inquiry response
5437                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5438                 name = NULL;
5439                 // Iterate over EIR data
5440                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5441                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5442                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5443                     const uint8_t * data = ad_iterator_get_data(&context);
5444                     // Prefer Complete Local Name over Shortened Local Name
5445                     switch (data_type){
5446                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5447                             if (name) continue;
5448                             /* fall through */
5449                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5450                             name = data;
5451                             name_len = data_size;
5452                             break;
5453                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5454                             if (data_size != 8) break;
5455                             event[16] = 1;
5456                             memcpy(&event[17], data, 8);
5457                             break;
5458                         default:
5459                             break;
5460                     }
5461                 }
5462                 if (name){
5463                     event[25] = 1;
5464                     // truncate name if needed
5465                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5466                     event[26] = len;
5467                     (void)memcpy(&event[27], name, len);
5468                     event_size += len;
5469                 }
5470                 break;
5471             default:
5472                 return;
5473         }
5474         event[1] = event_size - 2;
5475         hci_emit_event(event, event_size, 1);
5476     }
5477 }
5478 #endif
5479 
5480 void hci_emit_state(void){
5481     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5482     uint8_t event[3];
5483     event[0] = BTSTACK_EVENT_STATE;
5484     event[1] = sizeof(event) - 2u;
5485     event[2] = hci_stack->state;
5486     hci_emit_event(event, sizeof(event), 1);
5487 }
5488 
5489 #ifdef ENABLE_CLASSIC
5490 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5491     uint8_t event[13];
5492     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5493     event[1] = sizeof(event) - 2;
5494     event[2] = status;
5495     little_endian_store_16(event, 3, con_handle);
5496     reverse_bd_addr(address, &event[5]);
5497     event[11] = 1; // ACL connection
5498     event[12] = 0; // encryption disabled
5499     hci_emit_event(event, sizeof(event), 1);
5500 }
5501 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5502     if (disable_l2cap_timeouts) return;
5503     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5504     uint8_t event[4];
5505     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5506     event[1] = sizeof(event) - 2;
5507     little_endian_store_16(event, 2, conn->con_handle);
5508     hci_emit_event(event, sizeof(event), 1);
5509 }
5510 #endif
5511 
5512 #ifdef ENABLE_BLE
5513 #ifdef ENABLE_LE_CENTRAL
5514 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){
5515     uint8_t event[21];
5516     event[0] = HCI_EVENT_LE_META;
5517     event[1] = sizeof(event) - 2u;
5518     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5519     event[3] = status;
5520     little_endian_store_16(event, 4, con_handle);
5521     event[6] = 0; // TODO: role
5522     event[7] = address_type;
5523     reverse_bd_addr(address, &event[8]);
5524     little_endian_store_16(event, 14, 0); // interval
5525     little_endian_store_16(event, 16, 0); // latency
5526     little_endian_store_16(event, 18, 0); // supervision timeout
5527     event[20] = 0; // master clock accuracy
5528     hci_emit_event(event, sizeof(event), 1);
5529 }
5530 #endif
5531 #endif
5532 
5533 static void hci_emit_transport_packet_sent(void){
5534     // notify upper stack that it might be possible to send again
5535     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5536     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5537 }
5538 
5539 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5540     uint8_t event[6];
5541     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5542     event[1] = sizeof(event) - 2u;
5543     event[2] = 0; // status = OK
5544     little_endian_store_16(event, 3, con_handle);
5545     event[5] = reason;
5546     hci_emit_event(event, sizeof(event), 1);
5547 }
5548 
5549 static void hci_emit_nr_connections_changed(void){
5550     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5551     uint8_t event[3];
5552     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5553     event[1] = sizeof(event) - 2u;
5554     event[2] = nr_hci_connections();
5555     hci_emit_event(event, sizeof(event), 1);
5556 }
5557 
5558 static void hci_emit_hci_open_failed(void){
5559     log_info("BTSTACK_EVENT_POWERON_FAILED");
5560     uint8_t event[2];
5561     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5562     event[1] = sizeof(event) - 2u;
5563     hci_emit_event(event, sizeof(event), 1);
5564 }
5565 
5566 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5567     log_info("hci_emit_dedicated_bonding_result %u ", status);
5568     uint8_t event[9];
5569     int pos = 0;
5570     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5571     event[pos++] = sizeof(event) - 2u;
5572     event[pos++] = status;
5573     reverse_bd_addr(address, &event[pos]);
5574     hci_emit_event(event, sizeof(event), 1);
5575 }
5576 
5577 
5578 #ifdef ENABLE_CLASSIC
5579 
5580 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5581     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5582     uint8_t event[5];
5583     int pos = 0;
5584     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5585     event[pos++] = sizeof(event) - 2;
5586     little_endian_store_16(event, 2, con_handle);
5587     pos += 2;
5588     event[pos++] = level;
5589     hci_emit_event(event, sizeof(event), 1);
5590 }
5591 
5592 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5593     if (!connection) return LEVEL_0;
5594     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5595     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5596     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5597     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5598     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5599     // LEVEL 4 always requires 128 bit encrytion key size
5600     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5601         security_level = LEVEL_3;
5602     }
5603     return security_level;
5604 }
5605 
5606 static void hci_emit_discoverable_enabled(uint8_t enabled){
5607     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5608     uint8_t event[3];
5609     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5610     event[1] = sizeof(event) - 2;
5611     event[2] = enabled;
5612     hci_emit_event(event, sizeof(event), 1);
5613 }
5614 
5615 // query if remote side supports eSCO
5616 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5617     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5618     if (!connection) return false;
5619     return (connection->remote_supported_features[0] & 1) != 0;
5620 }
5621 
5622 static bool hci_ssp_supported(hci_connection_t * connection){
5623     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5624     return (connection->bonding_flags & mask) == mask;
5625 }
5626 
5627 // query if remote side supports SSP
5628 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5629     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5630     if (!connection) return false;
5631     return hci_ssp_supported(connection) ? 1 : 0;
5632 }
5633 
5634 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5635     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5636 }
5637 
5638 // GAP API
5639 /**
5640  * @bbrief enable/disable bonding. default is enabled
5641  * @praram enabled
5642  */
5643 void gap_set_bondable_mode(int enable){
5644     hci_stack->bondable = enable ? 1 : 0;
5645 }
5646 /**
5647  * @brief Get bondable mode.
5648  * @return 1 if bondable
5649  */
5650 int gap_get_bondable_mode(void){
5651     return hci_stack->bondable;
5652 }
5653 
5654 /**
5655  * @brief map link keys to security levels
5656  */
5657 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5658     switch (link_key_type){
5659         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5660             return LEVEL_4;
5661         case COMBINATION_KEY:
5662         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5663             return LEVEL_3;
5664         default:
5665             return LEVEL_2;
5666     }
5667 }
5668 
5669 /**
5670  * @brief map link keys to secure connection yes/no
5671  */
5672 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5673     switch (link_key_type){
5674         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5675         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5676             return 1;
5677         default:
5678             return 0;
5679     }
5680 }
5681 
5682 /**
5683  * @brief map link keys to authenticated
5684  */
5685 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5686     switch (link_key_type){
5687         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5688         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5689             return 1;
5690         default:
5691             return 0;
5692     }
5693 }
5694 
5695 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5696     log_info("gap_mitm_protection_required_for_security_level %u", level);
5697     return level > LEVEL_2;
5698 }
5699 
5700 /**
5701  * @brief get current security level
5702  */
5703 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5704     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5705     if (!connection) return LEVEL_0;
5706     return gap_security_level_for_connection(connection);
5707 }
5708 
5709 /**
5710  * @brief request connection to device to
5711  * @result GAP_AUTHENTICATION_RESULT
5712  */
5713 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5714     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5715     if (!connection){
5716         hci_emit_security_level(con_handle, LEVEL_0);
5717         return;
5718     }
5719 
5720     btstack_assert(hci_is_le_connection(connection) == false);
5721 
5722     // 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)
5723     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5724     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5725         requested_level = LEVEL_4;
5726     }
5727 
5728     gap_security_level_t current_level = gap_security_level(con_handle);
5729     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5730         requested_level, connection->requested_security_level, current_level);
5731 
5732     // authentication active if authentication request was sent or planned level > 0
5733     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5734     if (authentication_active){
5735         // authentication already active
5736         if (connection->requested_security_level < requested_level){
5737             // increase requested level as new level is higher
5738             // TODO: handle re-authentication when done
5739             connection->requested_security_level = requested_level;
5740         }
5741     } else {
5742         // no request active, notify if security sufficient
5743         if (requested_level <= current_level){
5744             hci_emit_security_level(con_handle, current_level);
5745             return;
5746         }
5747 
5748         // store request
5749         connection->requested_security_level = requested_level;
5750 
5751         // start to authenticate connection
5752         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5753         hci_run();
5754     }
5755 }
5756 
5757 /**
5758  * @brief start dedicated bonding with device. disconnect after bonding
5759  * @param device
5760  * @param request MITM protection
5761  * @result GAP_DEDICATED_BONDING_COMPLETE
5762  */
5763 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5764 
5765     // create connection state machine
5766     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5767 
5768     if (!connection){
5769         return BTSTACK_MEMORY_ALLOC_FAILED;
5770     }
5771 
5772     // delete linkn key
5773     gap_drop_link_key_for_bd_addr(device);
5774 
5775     // configure LEVEL_2/3, dedicated bonding
5776     connection->state = SEND_CREATE_CONNECTION;
5777     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5778     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5779     connection->bonding_flags = BONDING_DEDICATED;
5780 
5781     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5782 
5783     // handle: connnection failure (connection complete != ok)
5784     // handle: authentication failure
5785     // handle: disconnect on done
5786 
5787     hci_run();
5788 
5789     return 0;
5790 }
5791 
5792 void gap_set_local_name(const char * local_name){
5793     hci_stack->local_name = local_name;
5794     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5795     // also update EIR if not set by user
5796     if (hci_stack->eir_data == NULL){
5797         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5798     }
5799     hci_run();
5800 }
5801 #endif
5802 
5803 
5804 #ifdef ENABLE_BLE
5805 
5806 #ifdef ENABLE_LE_CENTRAL
5807 void gap_start_scan(void){
5808     hci_stack->le_scanning_enabled = true;
5809     hci_run();
5810 }
5811 
5812 void gap_stop_scan(void){
5813     hci_stack->le_scanning_enabled = false;
5814     hci_run();
5815 }
5816 
5817 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5818     hci_stack->le_scan_type          = scan_type;
5819     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5820     hci_stack->le_scan_interval      = scan_interval;
5821     hci_stack->le_scan_window        = scan_window;
5822     hci_stack->le_scanning_param_update = true;
5823     hci_run();
5824 }
5825 
5826 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5827     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5828 }
5829 
5830 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5831     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5832     if (!conn){
5833         // disallow if le connection is already outgoing
5834         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5835             log_error("le connection already active");
5836             return ERROR_CODE_COMMAND_DISALLOWED;
5837         }
5838 
5839         log_info("gap_connect: no connection exists yet, creating context");
5840         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5841         if (!conn){
5842             // notify client that alloc failed
5843             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5844             log_info("gap_connect: failed to alloc hci_connection_t");
5845             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5846         }
5847 
5848         // set le connecting state
5849         if (hci_is_le_connection_type(addr_type)){
5850             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5851         }
5852 
5853         conn->state = SEND_CREATE_CONNECTION;
5854         log_info("gap_connect: send create connection next");
5855         hci_run();
5856         return ERROR_CODE_SUCCESS;
5857     }
5858 
5859     if (!hci_is_le_connection(conn) ||
5860         (conn->state == SEND_CREATE_CONNECTION) ||
5861         (conn->state == SENT_CREATE_CONNECTION)) {
5862         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5863         log_error("gap_connect: classic connection or connect is already being created");
5864         return GATT_CLIENT_IN_WRONG_STATE;
5865     }
5866 
5867     // check if connection was just disconnected
5868     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5869         log_info("gap_connect: send create connection (again)");
5870         conn->state = SEND_CREATE_CONNECTION;
5871         hci_run();
5872         return ERROR_CODE_SUCCESS;
5873     }
5874 
5875     log_info("gap_connect: context exists with state %u", conn->state);
5876     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5877     hci_run();
5878     return ERROR_CODE_SUCCESS;
5879 }
5880 
5881 // @assumption: only a single outgoing LE Connection exists
5882 static hci_connection_t * gap_get_outgoing_connection(void){
5883     btstack_linked_item_t *it;
5884     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5885         hci_connection_t * conn = (hci_connection_t *) it;
5886         if (!hci_is_le_connection(conn)) continue;
5887         switch (conn->state){
5888             case SEND_CREATE_CONNECTION:
5889             case SENT_CREATE_CONNECTION:
5890             case SENT_CANCEL_CONNECTION:
5891                 return conn;
5892             default:
5893                 break;
5894         };
5895     }
5896     return NULL;
5897 }
5898 
5899 uint8_t gap_connect_cancel(void){
5900     hci_connection_t * conn = gap_get_outgoing_connection();
5901     if (!conn) return 0;
5902     switch (conn->state){
5903         case SEND_CREATE_CONNECTION:
5904             // skip sending create connection and emit event instead
5905             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5906             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5907             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5908             btstack_memory_hci_connection_free( conn );
5909             break;
5910         case SENT_CREATE_CONNECTION:
5911             // request to send cancel connection
5912             conn->state = SEND_CANCEL_CONNECTION;
5913             hci_run();
5914             break;
5915         default:
5916             break;
5917     }
5918     return 0;
5919 }
5920 #endif
5921 
5922 #ifdef ENABLE_LE_CENTRAL
5923 /**
5924  * @brief Set connection parameters for outgoing connections
5925  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5926  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5927  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5928  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5929  * @param conn_latency, default: 4
5930  * @param supervision_timeout (unit: 10ms), default: 720 ms
5931  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5932  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5933  */
5934 
5935 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5936     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5937     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5938     hci_stack->le_connection_scan_interval = conn_scan_interval;
5939     hci_stack->le_connection_scan_window = conn_scan_window;
5940     hci_stack->le_connection_interval_min = conn_interval_min;
5941     hci_stack->le_connection_interval_max = conn_interval_max;
5942     hci_stack->le_connection_latency = conn_latency;
5943     hci_stack->le_supervision_timeout = supervision_timeout;
5944     hci_stack->le_minimum_ce_length = min_ce_length;
5945     hci_stack->le_maximum_ce_length = max_ce_length;
5946 }
5947 #endif
5948 
5949 /**
5950  * @brief Updates the connection parameters for a given LE connection
5951  * @param handle
5952  * @param conn_interval_min (unit: 1.25ms)
5953  * @param conn_interval_max (unit: 1.25ms)
5954  * @param conn_latency
5955  * @param supervision_timeout (unit: 10ms)
5956  * @returns 0 if ok
5957  */
5958 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5959     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5960     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5961     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5962     connection->le_conn_interval_min = conn_interval_min;
5963     connection->le_conn_interval_max = conn_interval_max;
5964     connection->le_conn_latency = conn_latency;
5965     connection->le_supervision_timeout = supervision_timeout;
5966     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5967     hci_run();
5968     return 0;
5969 }
5970 
5971 /**
5972  * @brief Request an update of the connection parameter for a given LE connection
5973  * @param handle
5974  * @param conn_interval_min (unit: 1.25ms)
5975  * @param conn_interval_max (unit: 1.25ms)
5976  * @param conn_latency
5977  * @param supervision_timeout (unit: 10ms)
5978  * @returns 0 if ok
5979  */
5980 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5981     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5982     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5983     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5984     connection->le_conn_interval_min = conn_interval_min;
5985     connection->le_conn_interval_max = conn_interval_max;
5986     connection->le_conn_latency = conn_latency;
5987     connection->le_supervision_timeout = supervision_timeout;
5988     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5989     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5990     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5991     return 0;
5992 }
5993 
5994 #ifdef ENABLE_LE_PERIPHERAL
5995 
5996 /**
5997  * @brief Set Advertisement Data
5998  * @param advertising_data_length
5999  * @param advertising_data (max 31 octets)
6000  * @note data is not copied, pointer has to stay valid
6001  */
6002 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6003     hci_stack->le_advertisements_data_len = advertising_data_length;
6004     hci_stack->le_advertisements_data = advertising_data;
6005     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6006     hci_run();
6007 }
6008 
6009 /**
6010  * @brief Set Scan Response Data
6011  * @param advertising_data_length
6012  * @param advertising_data (max 31 octets)
6013  * @note data is not copied, pointer has to stay valid
6014  */
6015 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6016     hci_stack->le_scan_response_data_len = scan_response_data_length;
6017     hci_stack->le_scan_response_data = scan_response_data;
6018     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6019     hci_run();
6020 }
6021 
6022 /**
6023  * @brief Set Advertisement Parameters
6024  * @param adv_int_min
6025  * @param adv_int_max
6026  * @param adv_type
6027  * @param direct_address_type
6028  * @param direct_address
6029  * @param channel_map
6030  * @param filter_policy
6031  *
6032  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6033  */
6034  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6035     uint8_t direct_address_typ, bd_addr_t direct_address,
6036     uint8_t channel_map, uint8_t filter_policy) {
6037 
6038     hci_stack->le_advertisements_interval_min = adv_int_min;
6039     hci_stack->le_advertisements_interval_max = adv_int_max;
6040     hci_stack->le_advertisements_type = adv_type;
6041     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6042     hci_stack->le_advertisements_channel_map = channel_map;
6043     hci_stack->le_advertisements_filter_policy = filter_policy;
6044     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6045                  6);
6046 
6047     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6048     hci_run();
6049  }
6050 
6051 /**
6052  * @brief Enable/Disable Advertisements
6053  * @param enabled
6054  */
6055 void gap_advertisements_enable(int enabled){
6056     hci_stack->le_advertisements_enabled = enabled != 0;
6057     hci_update_advertisements_enabled_for_current_roles();
6058     hci_run();
6059 }
6060 
6061 #endif
6062 
6063 void hci_le_set_own_address_type(uint8_t own_address_type){
6064     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6065     if (own_address_type == hci_stack->le_own_addr_type) return;
6066     hci_stack->le_own_addr_type = own_address_type;
6067 
6068 #ifdef ENABLE_LE_PERIPHERAL
6069     // update advertisement parameters, too
6070     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6071     hci_run();
6072 #endif
6073 #ifdef ENABLE_LE_CENTRAL
6074     // note: we don't update scan parameters or modify ongoing connection attempts
6075 #endif
6076 }
6077 
6078 #endif
6079 
6080 uint8_t gap_disconnect(hci_con_handle_t handle){
6081     hci_connection_t * conn = hci_connection_for_handle(handle);
6082     if (!conn){
6083         hci_emit_disconnection_complete(handle, 0);
6084         return 0;
6085     }
6086     // ignore if already disconnected
6087     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6088         return 0;
6089     }
6090     conn->state = SEND_DISCONNECT;
6091     hci_run();
6092     return 0;
6093 }
6094 
6095 int gap_read_rssi(hci_con_handle_t con_handle){
6096     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6097     if (hci_connection == NULL) return 0;
6098     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6099     hci_run();
6100     return 1;
6101 }
6102 
6103 /**
6104  * @brief Get connection type
6105  * @param con_handle
6106  * @result connection_type
6107  */
6108 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6109     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6110     if (!conn) return GAP_CONNECTION_INVALID;
6111     switch (conn->address_type){
6112         case BD_ADDR_TYPE_LE_PUBLIC:
6113         case BD_ADDR_TYPE_LE_RANDOM:
6114             return GAP_CONNECTION_LE;
6115         case BD_ADDR_TYPE_SCO:
6116             return GAP_CONNECTION_SCO;
6117         case BD_ADDR_TYPE_ACL:
6118             return GAP_CONNECTION_ACL;
6119         default:
6120             return GAP_CONNECTION_INVALID;
6121     }
6122 }
6123 
6124 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6125     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6126     if (!conn) return HCI_ROLE_INVALID;
6127     return (hci_role_t) conn->role;
6128 }
6129 
6130 
6131 #ifdef ENABLE_CLASSIC
6132 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6133     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6134     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6135     conn->request_role = role;
6136     hci_run();
6137     return ERROR_CODE_SUCCESS;
6138 }
6139 #endif
6140 
6141 #ifdef ENABLE_BLE
6142 
6143 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){
6144     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6145     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6146 
6147     conn->le_phy_update_all_phys    = all_phys;
6148     conn->le_phy_update_tx_phys     = tx_phys;
6149     conn->le_phy_update_rx_phys     = rx_phys;
6150     conn->le_phy_update_phy_options = phy_options;
6151 
6152     hci_run();
6153 
6154     return 0;
6155 }
6156 
6157 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6158     // check if already in list
6159     btstack_linked_list_iterator_t it;
6160     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6161     while (btstack_linked_list_iterator_has_next(&it)) {
6162         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6163         if (entry->address_type != address_type) {
6164             continue;
6165         }
6166         if (memcmp(entry->address, address, 6) != 0) {
6167             continue;
6168         }
6169 		// disallow if already scheduled to add
6170 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6171 			return ERROR_CODE_COMMAND_DISALLOWED;
6172 		}
6173 		// still on controller, but scheduled to remove -> re-add
6174 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6175 		return ERROR_CODE_SUCCESS;
6176     }
6177     // alloc and add to list
6178     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6179     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6180     entry->address_type = address_type;
6181     (void)memcpy(entry->address, address, 6);
6182     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6183     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6184     return ERROR_CODE_SUCCESS;
6185 }
6186 
6187 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6188     btstack_linked_list_iterator_t it;
6189     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6190     while (btstack_linked_list_iterator_has_next(&it)){
6191         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6192         if (entry->address_type != address_type) {
6193             continue;
6194         }
6195         if (memcmp(entry->address, address, 6) != 0) {
6196             continue;
6197         }
6198         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6199             // remove from controller if already present
6200             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6201         }  else {
6202             // directly remove entry from whitelist
6203             btstack_linked_list_iterator_remove(&it);
6204             btstack_memory_whitelist_entry_free(entry);
6205         }
6206         return ERROR_CODE_SUCCESS;
6207     }
6208     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6209 }
6210 
6211 static void hci_whitelist_clear(void){
6212     btstack_linked_list_iterator_t it;
6213     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6214     while (btstack_linked_list_iterator_has_next(&it)){
6215         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6216         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6217             // remove from controller if already present
6218             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6219             continue;
6220         }
6221         // directly remove entry from whitelist
6222         btstack_linked_list_iterator_remove(&it);
6223         btstack_memory_whitelist_entry_free(entry);
6224     }
6225 }
6226 
6227 /**
6228  * @brief Clear Whitelist
6229  * @returns 0 if ok
6230  */
6231 uint8_t gap_whitelist_clear(void){
6232     hci_whitelist_clear();
6233     hci_run();
6234     return ERROR_CODE_SUCCESS;
6235 }
6236 
6237 /**
6238  * @brief Add Device to Whitelist
6239  * @param address_typ
6240  * @param address
6241  * @returns 0 if ok
6242  */
6243 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6244     uint8_t status = hci_whitelist_add(address_type, address);
6245     if (status){
6246         return status;
6247     }
6248     hci_run();
6249     return ERROR_CODE_SUCCESS;
6250 }
6251 
6252 /**
6253  * @brief Remove Device from Whitelist
6254  * @param address_typ
6255  * @param address
6256  * @returns 0 if ok
6257  */
6258 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6259     uint8_t status = hci_whitelist_remove(address_type, address);
6260     if (status){
6261         return status;
6262     }
6263     hci_run();
6264     return ERROR_CODE_SUCCESS;
6265 }
6266 
6267 #ifdef ENABLE_LE_CENTRAL
6268 /**
6269  *  @brief Connect with Whitelist
6270  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6271  *  @returns - if ok
6272  */
6273 uint8_t gap_connect_with_whitelist(void){
6274     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6275         return ERROR_CODE_COMMAND_DISALLOWED;
6276     }
6277     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6278     hci_run();
6279     return ERROR_CODE_SUCCESS;
6280 }
6281 
6282 /**
6283  * @brief Auto Connection Establishment - Start Connecting to device
6284  * @param address_typ
6285  * @param address
6286  * @returns 0 if ok
6287  */
6288 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6289     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6290         return ERROR_CODE_COMMAND_DISALLOWED;
6291     }
6292 
6293     uint8_t status = hci_whitelist_add(address_type, address);
6294     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6295         return status;
6296     }
6297 
6298     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6299 
6300     hci_run();
6301     return ERROR_CODE_SUCCESS;
6302 }
6303 
6304 /**
6305  * @brief Auto Connection Establishment - Stop Connecting to device
6306  * @param address_typ
6307  * @param address
6308  * @returns 0 if ok
6309  */
6310 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6311     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6312         return ERROR_CODE_COMMAND_DISALLOWED;
6313     }
6314 
6315     hci_whitelist_remove(address_type, address);
6316     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6317         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6318     }
6319     hci_run();
6320     return 0;
6321 }
6322 
6323 /**
6324  * @brief Auto Connection Establishment - Stop everything
6325  * @note  Convenience function to stop all active auto connection attempts
6326  */
6327 uint8_t gap_auto_connection_stop_all(void){
6328     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6329         return ERROR_CODE_COMMAND_DISALLOWED;
6330     }
6331     hci_whitelist_clear();
6332     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6333     hci_run();
6334     return ERROR_CODE_SUCCESS;
6335 }
6336 
6337 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6338     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6339     if (!conn) return 0;
6340     return conn->le_connection_interval;
6341 }
6342 #endif
6343 #endif
6344 
6345 #ifdef ENABLE_CLASSIC
6346 /**
6347  * @brief Set Extended Inquiry Response data
6348  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6349  * @note has to be done before stack starts up
6350  */
6351 void gap_set_extended_inquiry_response(const uint8_t * data){
6352     hci_stack->eir_data = data;
6353     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6354     hci_run();
6355 }
6356 
6357 /**
6358  * @brief Start GAP Classic Inquiry
6359  * @param duration in 1.28s units
6360  * @return 0 if ok
6361  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6362  */
6363 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6364     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6365     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6366     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6367         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6368     }
6369     hci_stack->inquiry_state = duration_in_1280ms_units;
6370     hci_run();
6371     return 0;
6372 }
6373 
6374 /**
6375  * @brief Stop GAP Classic Inquiry
6376  * @returns 0 if ok
6377  */
6378 int gap_inquiry_stop(void){
6379     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6380         // emit inquiry complete event, before it even started
6381         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6382         hci_emit_event(event, sizeof(event), 1);
6383         return 0;
6384     }
6385     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6386     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6387     hci_run();
6388     return 0;
6389 }
6390 
6391 void gap_inquiry_set_lap(uint32_t lap){
6392     hci_stack->inquiry_lap = lap;
6393 }
6394 
6395 
6396 /**
6397  * @brief Remote Name Request
6398  * @param addr
6399  * @param page_scan_repetition_mode
6400  * @param clock_offset only used when bit 15 is set
6401  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6402  */
6403 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6404     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6405     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6406     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6407     hci_stack->remote_name_clock_offset = clock_offset;
6408     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6409     hci_run();
6410     return 0;
6411 }
6412 
6413 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6414     hci_stack->gap_pairing_state = state;
6415     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6416     hci_run();
6417     return 0;
6418 }
6419 
6420 /**
6421  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6422  * @param addr
6423  * @param pin_data
6424  * @param pin_len
6425  * @return 0 if ok
6426  */
6427 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6428     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6429     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6430     hci_stack->gap_pairing_pin_len = pin_len;
6431     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6432 }
6433 
6434 /**
6435  * @brief Legacy Pairing Pin Code Response
6436  * @param addr
6437  * @param pin
6438  * @return 0 if ok
6439  */
6440 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6441     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6442 }
6443 
6444 /**
6445  * @brief Abort Legacy Pairing
6446  * @param addr
6447  * @param pin
6448  * @return 0 if ok
6449  */
6450 int gap_pin_code_negative(bd_addr_t addr){
6451     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6452     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6453 }
6454 
6455 /**
6456  * @brief SSP Passkey Response
6457  * @param addr
6458  * @param passkey
6459  * @return 0 if ok
6460  */
6461 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6462     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6463     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6464     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6465 }
6466 
6467 /**
6468  * @brief Abort SSP Passkey Entry/Pairing
6469  * @param addr
6470  * @param pin
6471  * @return 0 if ok
6472  */
6473 int gap_ssp_passkey_negative(const bd_addr_t addr){
6474     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6475     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6476 }
6477 
6478 /**
6479  * @brief Accept SSP Numeric Comparison
6480  * @param addr
6481  * @param passkey
6482  * @return 0 if ok
6483  */
6484 int gap_ssp_confirmation_response(const bd_addr_t addr){
6485     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6486     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6487 }
6488 
6489 /**
6490  * @brief Abort SSP Numeric Comparison/Pairing
6491  * @param addr
6492  * @param pin
6493  * @return 0 if ok
6494  */
6495 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6496     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6497     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6498 }
6499 
6500 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6501 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6502     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6503     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6504     connectionSetAuthenticationFlags(conn, flag);
6505     hci_run();
6506     return ERROR_CODE_SUCCESS;
6507 }
6508 #endif
6509 
6510 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6511 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6512     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6513 }
6514 
6515 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6516     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6517 }
6518 #endif
6519 
6520 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6521 /**
6522  * @brief Report Remote OOB Data
6523  * @param bd_addr
6524  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6525  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6526  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6527  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6528  */
6529 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){
6530     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6531     if (connection == NULL) {
6532         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6533     }
6534     connection->classic_oob_c_192 = c_192;
6535     connection->classic_oob_r_192 = r_192;
6536 
6537     // ignore P-256 if not supported by us
6538     if (hci_stack->secure_connections_active){
6539         connection->classic_oob_c_256 = c_256;
6540         connection->classic_oob_r_256 = r_256;
6541     }
6542 
6543     return ERROR_CODE_SUCCESS;
6544 }
6545 /**
6546  * @brief Generate new OOB data
6547  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6548  */
6549 void gap_ssp_generate_oob_data(void){
6550     hci_stack->classic_read_local_oob_data = true;
6551     hci_run();
6552 }
6553 
6554 #endif
6555 
6556 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6557 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6558     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6559     if (connection == NULL) {
6560         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6561     }
6562 
6563     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6564     connection->link_key_type = type;
6565 
6566     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6567 }
6568 
6569 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6570 /**
6571  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6572  * @param inquiry_mode see bluetooth_defines.h
6573  */
6574 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6575     hci_stack->inquiry_mode = inquiry_mode;
6576 }
6577 
6578 /**
6579  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6580  */
6581 void hci_set_sco_voice_setting(uint16_t voice_setting){
6582     hci_stack->sco_voice_setting = voice_setting;
6583 }
6584 
6585 /**
6586  * @brief Get SCO Voice Setting
6587  * @return current voice setting
6588  */
6589 uint16_t hci_get_sco_voice_setting(void){
6590     return hci_stack->sco_voice_setting;
6591 }
6592 
6593 static int hci_have_usb_transport(void){
6594     if (!hci_stack->hci_transport) return 0;
6595     const char * transport_name = hci_stack->hci_transport->name;
6596     if (!transport_name) return 0;
6597     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6598 }
6599 
6600 /** @brief Get SCO packet length for current SCO Voice setting
6601  *  @note  Using SCO packets of the exact length is required for USB transfer
6602  *  @return Length of SCO packets in bytes (not audio frames)
6603  */
6604 uint16_t hci_get_sco_packet_length(void){
6605     uint16_t sco_packet_length = 0;
6606 
6607 #ifdef ENABLE_SCO_OVER_HCI
6608     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6609     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6610 
6611     if (hci_have_usb_transport()){
6612         // see Core Spec for H2 USB Transfer.
6613         // 3 byte SCO header + 24 bytes per connection
6614         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6615         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6616     } else {
6617         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6618         sco_packet_length = 3 + 60 * multiplier;
6619         // assert that it still fits inside an SCO buffer
6620         if (sco_packet_length > hci_stack->sco_data_packet_length){
6621             sco_packet_length = 3 + 60;
6622         }
6623     }
6624 #endif
6625 
6626 #ifdef HAVE_SCO_TRANSPORT
6627     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6628     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6629     sco_packet_length = 3 + 60 * multiplier;
6630 #endif
6631     return sco_packet_length;
6632 }
6633 
6634 /**
6635 * @brief Sets the master/slave policy
6636 * @param policy (0: attempt to become master, 1: let connecting device decide)
6637 */
6638 void hci_set_master_slave_policy(uint8_t policy){
6639     hci_stack->master_slave_policy = policy;
6640 }
6641 
6642 #endif
6643 
6644 HCI_STATE hci_get_state(void){
6645     return hci_stack->state;
6646 }
6647 
6648 #ifdef ENABLE_CLASSIC
6649 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6650     hci_stack->gap_classic_accept_callback = accept_callback;
6651 }
6652 #endif
6653 
6654 /**
6655  * @brief Set callback for Bluetooth Hardware Error
6656  */
6657 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6658     hci_stack->hardware_error_callback = fn;
6659 }
6660 
6661 void hci_disconnect_all(void){
6662     btstack_linked_list_iterator_t it;
6663     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6664     while (btstack_linked_list_iterator_has_next(&it)){
6665         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6666         if (con->state == SENT_DISCONNECT) continue;
6667         con->state = SEND_DISCONNECT;
6668     }
6669     hci_run();
6670 }
6671 
6672 uint16_t hci_get_manufacturer(void){
6673     return hci_stack->manufacturer;
6674 }
6675 
6676 #ifdef ENABLE_BLE
6677 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6678     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6679     if (!hci_con) return NULL;
6680     return &hci_con->sm_connection;
6681 }
6682 
6683 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6684 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6685 #endif
6686 
6687 int gap_encryption_key_size(hci_con_handle_t con_handle){
6688     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6689     if (hci_connection == NULL) return 0;
6690     if (hci_is_le_connection(hci_connection)){
6691 #ifdef ENABLE_BLE
6692         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6693         if (sm_conn->sm_connection_encrypted) {
6694             return sm_conn->sm_actual_encryption_key_size;
6695         }
6696 #endif
6697     } else {
6698 #ifdef ENABLE_CLASSIC
6699         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6700             return hci_connection->encryption_key_size;
6701         }
6702 #endif
6703     }
6704     return 0;
6705 }
6706 
6707 int gap_authenticated(hci_con_handle_t con_handle){
6708     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6709     if (hci_connection == NULL) return 0;
6710 
6711     switch (hci_connection->address_type){
6712 #ifdef ENABLE_BLE
6713         case BD_ADDR_TYPE_LE_PUBLIC:
6714         case BD_ADDR_TYPE_LE_RANDOM:
6715             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6716             return hci_connection->sm_connection.sm_connection_authenticated;
6717 #endif
6718 #ifdef ENABLE_CLASSIC
6719         case BD_ADDR_TYPE_SCO:
6720         case BD_ADDR_TYPE_ACL:
6721             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6722 #endif
6723         default:
6724             return 0;
6725     }
6726 }
6727 
6728 int gap_secure_connection(hci_con_handle_t con_handle){
6729     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6730     if (hci_connection == NULL) return 0;
6731 
6732     switch (hci_connection->address_type){
6733 #ifdef ENABLE_BLE
6734         case BD_ADDR_TYPE_LE_PUBLIC:
6735         case BD_ADDR_TYPE_LE_RANDOM:
6736             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6737             return hci_connection->sm_connection.sm_connection_sc;
6738 #endif
6739 #ifdef ENABLE_CLASSIC
6740         case BD_ADDR_TYPE_SCO:
6741         case BD_ADDR_TYPE_ACL:
6742             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6743 #endif
6744         default:
6745             return 0;
6746     }
6747 }
6748 
6749 bool gap_bonded(hci_con_handle_t con_handle){
6750 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6751 	if (hci_connection == NULL) return 0;
6752 
6753 #ifdef ENABLE_CLASSIC
6754 	link_key_t link_key;
6755 	link_key_type_t link_key_type;
6756 #endif
6757 	switch (hci_connection->address_type){
6758 #ifdef ENABLE_BLE
6759 		case BD_ADDR_TYPE_LE_PUBLIC:
6760 		case BD_ADDR_TYPE_LE_RANDOM:
6761 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6762 #endif
6763 #ifdef ENABLE_CLASSIC
6764 		case BD_ADDR_TYPE_SCO:
6765 		case BD_ADDR_TYPE_ACL:
6766 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6767 #endif
6768 		default:
6769 			return false;
6770 	}
6771 }
6772 
6773 #ifdef ENABLE_BLE
6774 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6775     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6776     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6777     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6778     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6779     return sm_conn->sm_connection_authorization_state;
6780 }
6781 #endif
6782 
6783 #ifdef ENABLE_CLASSIC
6784 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){
6785     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6786     if (!conn) return GAP_CONNECTION_INVALID;
6787     conn->sniff_min_interval = sniff_min_interval;
6788     conn->sniff_max_interval = sniff_max_interval;
6789     conn->sniff_attempt = sniff_attempt;
6790     conn->sniff_timeout = sniff_timeout;
6791     hci_run();
6792     return 0;
6793 }
6794 
6795 /**
6796  * @brief Exit Sniff mode
6797  * @param con_handle
6798  @ @return 0 if ok
6799  */
6800 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6801     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6802     if (!conn) return GAP_CONNECTION_INVALID;
6803     conn->sniff_min_interval = 0xffff;
6804     hci_run();
6805     return 0;
6806 }
6807 
6808 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){
6809     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6810     if (!conn) return GAP_CONNECTION_INVALID;
6811     conn->sniff_subrating_max_latency = max_latency;
6812     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6813     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6814     hci_run();
6815     return ERROR_CODE_SUCCESS;
6816 }
6817 
6818 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){
6819     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6820     if (!conn) return GAP_CONNECTION_INVALID;
6821     conn->qos_service_type = service_type;
6822     conn->qos_token_rate = token_rate;
6823     conn->qos_peak_bandwidth = peak_bandwidth;
6824     conn->qos_latency = latency;
6825     conn->qos_delay_variation = delay_variation;
6826     hci_run();
6827     return ERROR_CODE_SUCCESS;
6828 }
6829 
6830 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6831     hci_stack->new_page_scan_interval = page_scan_interval;
6832     hci_stack->new_page_scan_window = page_scan_window;
6833     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6834     hci_run();
6835 }
6836 
6837 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6838     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6839     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6840     hci_run();
6841 }
6842 
6843 #endif
6844 
6845 void hci_halting_defer(void){
6846     if (hci_stack->state != HCI_STATE_HALTING) return;
6847     switch (hci_stack->substate){
6848         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6849         case HCI_HALTING_CLOSE:
6850             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6851             break;
6852         default:
6853             break;
6854     }
6855 }
6856 
6857 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6858 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6859     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6860     if (le_device_db_index >= le_device_db_max_count()) return;
6861     uint8_t offset = le_device_db_index >> 3;
6862     uint8_t mask = 1 << (le_device_db_index & 7);
6863     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6864     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6865     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6866         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6867     }
6868 }
6869 
6870 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6871 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6872 	if (le_device_db_index >= le_device_db_max_count()) return;
6873 	uint8_t offset = le_device_db_index >> 3;
6874 	uint8_t mask = 1 << (le_device_db_index & 7);
6875 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6876 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6877 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6878 	}
6879 }
6880 
6881 uint8_t gap_load_resolving_list_from_le_device_db(void){
6882 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6883 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6884 	}
6885 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6886 		// restart le resolving list update
6887 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6888 	}
6889 	return ERROR_CODE_SUCCESS;
6890 }
6891 #endif
6892 
6893 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6894 void hci_setup_test_connections_fuzz(void){
6895     hci_connection_t * conn;
6896 
6897     // default address: 66:55:44:33:00:01
6898     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6899 
6900     // setup Controller info
6901     hci_stack->num_cmd_packets = 255;
6902     hci_stack->acl_packets_total_num = 255;
6903 
6904     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6905     addr[5] = 0x01;
6906     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6907     conn->con_handle = addr[5];
6908     conn->role  = HCI_ROLE_SLAVE;
6909     conn->state = RECEIVED_CONNECTION_REQUEST;
6910     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6911 
6912     // setup incoming Classic SCO connection with con handle 0x0002
6913     addr[5] = 0x02;
6914     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6915     conn->con_handle = addr[5];
6916     conn->role  = HCI_ROLE_SLAVE;
6917     conn->state = RECEIVED_CONNECTION_REQUEST;
6918     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6919 
6920     // setup ready Classic ACL connection with con handle 0x0003
6921     addr[5] = 0x03;
6922     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6923     conn->con_handle = addr[5];
6924     conn->role  = HCI_ROLE_SLAVE;
6925     conn->state = OPEN;
6926     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6927 
6928     // setup ready Classic SCO connection with con handle 0x0004
6929     addr[5] = 0x04;
6930     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6931     conn->con_handle = addr[5];
6932     conn->role  = HCI_ROLE_SLAVE;
6933     conn->state = OPEN;
6934     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6935 
6936     // setup ready LE ACL connection with con handle 0x005 and public address
6937     addr[5] = 0x05;
6938     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6939     conn->con_handle = addr[5];
6940     conn->role  = HCI_ROLE_SLAVE;
6941     conn->state = OPEN;
6942     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6943     conn->sm_connection.sm_connection_encrypted = 1;
6944 }
6945 
6946 void hci_free_connections_fuzz(void){
6947     btstack_linked_list_iterator_t it;
6948     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6949     while (btstack_linked_list_iterator_has_next(&it)){
6950         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6951         btstack_linked_list_iterator_remove(&it);
6952         btstack_memory_hci_connection_free(con);
6953     }
6954 }
6955 void hci_simulate_working_fuzz(void){
6956     hci_init_done();
6957     hci_stack->num_cmd_packets = 255;
6958 }
6959 #endif
6960