xref: /btstack/src/hci.c (revision 284d66bc610cd8551d4dce75d1f6cc77a02d16f0)
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 BLUEKITCHEN
24  * GMBH 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_halting_timeout_handler(btstack_timer_source_t * ds);
156 static void hci_emit_transport_packet_sent(void);
157 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
158 static void hci_emit_nr_connections_changed(void);
159 static void hci_emit_hci_open_failed(void);
160 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
161 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
162 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
163 static void hci_run(void);
164 static int  hci_is_le_connection(hci_connection_t * connection);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection);
169 #endif
170 
171 #ifdef ENABLE_BLE
172 #ifdef ENABLE_LE_CENTRAL
173 // called from test/ble_client/advertising_data_parser.c
174 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
175 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
176 static void hci_whitelist_free(void);
177 static hci_connection_t * gap_get_outgoing_connection(void);
178 #endif
179 #endif
180 
181 // the STACK is here
182 #ifndef HAVE_MALLOC
183 static hci_stack_t   hci_stack_static;
184 #endif
185 static hci_stack_t * hci_stack = NULL;
186 
187 #ifdef ENABLE_CLASSIC
188 // default name
189 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
190 
191 // test helper
192 static uint8_t disable_l2cap_timeouts = 0;
193 #endif
194 
195 // reset connection state on create and on reconnect
196 // don't overwrite addr, con handle, role
197 static void hci_connection_init(hci_connection_t * conn){
198     conn->authentication_flags = AUTH_FLAG_NONE;
199     conn->bonding_flags = 0;
200     conn->requested_security_level = LEVEL_0;
201 #ifdef ENABLE_CLASSIC
202     conn->request_role = HCI_ROLE_INVALID;
203     conn->sniff_subrating_max_latency = 0xffff;
204     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
205     conn->link_key_type = INVALID_LINK_KEY;
206     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
207     btstack_run_loop_set_timer_context(&conn->timeout, conn);
208     hci_connection_timestamp(conn);
209 #endif
210     conn->acl_recombination_length = 0;
211     conn->acl_recombination_pos = 0;
212     conn->num_packets_sent = 0;
213 
214     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
215 #ifdef ENABLE_BLE
216     conn->le_phy_update_all_phys = 0xff;
217 #endif
218 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
219     conn->le_max_tx_octets = 27;
220 #endif
221 #ifdef ENABLE_CLASSIC_PAIRING_OOB
222     conn->classic_oob_c_192 = NULL;
223     conn->classic_oob_r_192 = NULL;
224     conn->classic_oob_c_256 = NULL;
225     conn->classic_oob_r_256 = NULL;
226 #endif
227 }
228 
229 /**
230  * create connection for given address
231  *
232  * @return connection OR NULL, if no memory left
233  */
234 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
235     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
236 
237     hci_connection_t * conn = btstack_memory_hci_connection_get();
238     if (!conn) return NULL;
239     hci_connection_init(conn);
240 
241     bd_addr_copy(conn->address, addr);
242     conn->address_type = addr_type;
243     conn->con_handle = HCI_CON_HANDLE_INVALID;
244     conn->role = HCI_ROLE_INVALID;
245 
246     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
247 
248     return conn;
249 }
250 
251 
252 /**
253  * get le connection parameter range
254 *
255  * @return le connection parameter range struct
256  */
257 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
258     *range = hci_stack->le_connection_parameter_range;
259 }
260 
261 /**
262  * set le connection parameter range
263  *
264  */
265 
266 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
267     hci_stack->le_connection_parameter_range = *range;
268 }
269 
270 /**
271  * @brief Test if connection parameters are inside in existing rage
272  * @param conn_interval_min (unit: 1.25ms)
273  * @param conn_interval_max (unit: 1.25ms)
274  * @param conn_latency
275  * @param supervision_timeout (unit: 10ms)
276  * @return 1 if included
277  */
278 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){
279     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
280     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
281 
282     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
283     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
284 
285     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
286     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
287 
288     return 1;
289 }
290 
291 /**
292  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
293  * @note: default: 1
294  * @param max_peripheral_connections
295  */
296 #ifdef ENABLE_LE_PERIPHERAL
297 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
298     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
299 }
300 #endif
301 
302 /**
303  * get hci connections iterator
304  *
305  * @return hci connections iterator
306  */
307 
308 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
309     btstack_linked_list_iterator_init(it, &hci_stack->connections);
310 }
311 
312 /**
313  * get connection for a given handle
314  *
315  * @return connection OR NULL, if not found
316  */
317 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
318     btstack_linked_list_iterator_t it;
319     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
320     while (btstack_linked_list_iterator_has_next(&it)){
321         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
322         if ( item->con_handle == con_handle ) {
323             return item;
324         }
325     }
326     return NULL;
327 }
328 
329 /**
330  * get connection for given address
331  *
332  * @return connection OR NULL, if not found
333  */
334 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
335     btstack_linked_list_iterator_t it;
336     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
337     while (btstack_linked_list_iterator_has_next(&it)){
338         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
339         if (connection->address_type != addr_type)  continue;
340         if (memcmp(addr, connection->address, 6) != 0) continue;
341         return connection;
342     }
343     return NULL;
344 }
345 
346 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
347     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
348 }
349 
350 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
351     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
352 }
353 
354 #ifdef ENABLE_CLASSIC
355 
356 #ifdef ENABLE_SCO_OVER_HCI
357 static int hci_number_sco_connections(void){
358     int connections = 0;
359     btstack_linked_list_iterator_t it;
360     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
361     while (btstack_linked_list_iterator_has_next(&it)){
362         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
363         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
364         connections++;
365     }
366     return connections;
367 }
368 #endif
369 
370 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
371     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
372 #ifdef HAVE_EMBEDDED_TICK
373     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
374         // connections might be timed out
375         hci_emit_l2cap_check_timeout(connection);
376     }
377 #else
378     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
379         // connections might be timed out
380         hci_emit_l2cap_check_timeout(connection);
381     }
382 #endif
383 }
384 
385 static void hci_connection_timestamp(hci_connection_t *connection){
386 #ifdef HAVE_EMBEDDED_TICK
387     connection->timestamp = btstack_run_loop_embedded_get_ticks();
388 #else
389     connection->timestamp = btstack_run_loop_get_time_ms();
390 #endif
391 }
392 
393 /**
394  * add authentication flags and reset timer
395  * @note: assumes classic connection
396  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
397  */
398 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
399     bd_addr_t addr;
400     reverse_bd_addr(bd_addr, addr);
401     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
402     if (conn) {
403         connectionSetAuthenticationFlags(conn, flags);
404         hci_connection_timestamp(conn);
405     }
406 }
407 
408 static bool hci_pairing_active(hci_connection_t * hci_connection){
409     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
410 }
411 
412 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
413     if (hci_pairing_active(hci_connection)) return;
414     if (ssp){
415         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
416     } else {
417         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
418     }
419     // if we are initiator, we have sent an HCI Authenticate Request
420     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
421 
422     // if we are responder, use minimal service security level as required level
423     if (!initiator){
424         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);
425     }
426 
427     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
428 
429     uint8_t event[12];
430     event[0] = GAP_EVENT_PAIRING_STARTED;
431     event[1] = 10;
432     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
433     reverse_bd_addr(hci_connection->address, &event[4]);
434     event[10] = (uint8_t) ssp;
435     event[11] = (uint8_t) initiator;
436     hci_emit_event(event, sizeof(event), 1);
437 }
438 
439 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
440     hci_connection->requested_security_level = LEVEL_0;
441     if (!hci_pairing_active(hci_connection)) return;
442     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
443 #ifdef ENABLE_CLASSIC_PAIRING_OOB
444     hci_connection->classic_oob_c_192 = NULL;
445     hci_connection->classic_oob_r_192 = NULL;
446     hci_connection->classic_oob_c_256 = NULL;
447     hci_connection->classic_oob_r_256 = NULL;
448 #endif
449     log_info("pairing complete, status %02x", status);
450 
451     uint8_t event[11];
452     event[0] = GAP_EVENT_PAIRING_COMPLETE;
453     event[1] = 9;
454     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
455     reverse_bd_addr(hci_connection->address, &event[4]);
456     event[10] = status;
457     hci_emit_event(event, sizeof(event), 1);
458 }
459 
460 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
461     hci_connection_t * conn = hci_connection_for_handle(handle);
462     if (!conn) return false;
463     return hci_pairing_active(conn);
464 }
465 
466 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
467     if (!hci_stack->link_key_db) return;
468     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
469     hci_stack->link_key_db->delete_link_key(addr);
470 }
471 
472 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
473     if (!hci_stack->link_key_db) return;
474     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
475     hci_stack->link_key_db->put_link_key(addr, link_key, type);
476 }
477 
478 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
479 	if (!hci_stack->link_key_db) return false;
480 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
481 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
482 	return result;
483 }
484 
485 void gap_delete_all_link_keys(void){
486     bd_addr_t  addr;
487     link_key_t link_key;
488     link_key_type_t type;
489     btstack_link_key_iterator_t it;
490     int ok = gap_link_key_iterator_init(&it);
491     if (!ok) {
492         log_error("could not initialize iterator");
493         return;
494     }
495     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
496         gap_drop_link_key_for_bd_addr(addr);
497     }
498     gap_link_key_iterator_done(&it);
499 }
500 
501 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
502     if (!hci_stack->link_key_db) return 0;
503     if (!hci_stack->link_key_db->iterator_init) return 0;
504     return hci_stack->link_key_db->iterator_init(it);
505 }
506 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){
507     if (!hci_stack->link_key_db) return 0;
508     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
509 }
510 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
511     if (!hci_stack->link_key_db) return;
512     hci_stack->link_key_db->iterator_done(it);
513 }
514 #endif
515 
516 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
517     switch (address_type){
518         case BD_ADDR_TYPE_LE_PUBLIC:
519         case BD_ADDR_TYPE_LE_RANDOM:
520         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
521         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
522             return true;
523         default:
524             return false;
525     }
526 }
527 
528 static int hci_is_le_connection(hci_connection_t * connection){
529     return hci_is_le_connection_type(connection->address_type);
530 }
531 
532 /**
533  * count connections
534  */
535 static int nr_hci_connections(void){
536     int count = 0;
537     btstack_linked_item_t *it;
538     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
539         count++;
540     }
541     return count;
542 }
543 
544 uint16_t hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
545 
546     unsigned int num_packets_sent_classic = 0;
547     unsigned int num_packets_sent_le = 0;
548 
549     btstack_linked_item_t *it;
550     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
551         hci_connection_t * connection = (hci_connection_t *) it;
552         if (hci_is_le_connection(connection)){
553             num_packets_sent_le += connection->num_packets_sent;
554         }
555         if (connection->address_type == BD_ADDR_TYPE_ACL){
556             num_packets_sent_classic += connection->num_packets_sent;
557         }
558     }
559     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
560     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
561     int free_slots_le = 0;
562 
563     if (free_slots_classic < 0){
564         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);
565         return 0;
566     }
567 
568     if (hci_stack->le_acl_packets_total_num){
569         // if we have LE slots, they are used
570         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
571         if (free_slots_le < 0){
572             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);
573             return 0;
574         }
575     } else {
576         // otherwise, classic slots are used for LE, too
577         free_slots_classic -= num_packets_sent_le;
578         if (free_slots_classic < 0){
579             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);
580             return 0;
581         }
582     }
583 
584     switch (address_type){
585         case BD_ADDR_TYPE_UNKNOWN:
586             log_error("hci_number_free_acl_slots: unknown address type");
587             return 0;
588 
589         case BD_ADDR_TYPE_ACL:
590             return (uint16_t) free_slots_classic;
591 
592         default:
593            if (hci_stack->le_acl_packets_total_num > 0){
594                return (uint16_t) free_slots_le;
595            }
596            return (uint16_t) free_slots_classic;
597     }
598 }
599 
600 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
601     // get connection type
602     hci_connection_t * connection = hci_connection_for_handle(con_handle);
603     if (!connection){
604         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
605         return 0;
606     }
607     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
608 }
609 
610 #ifdef ENABLE_CLASSIC
611 static int hci_number_free_sco_slots(void){
612     unsigned int num_sco_packets_sent  = 0;
613     btstack_linked_item_t *it;
614     if (hci_stack->synchronous_flow_control_enabled){
615         // explicit flow control
616         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
617             hci_connection_t * connection = (hci_connection_t *) it;
618             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
619             num_sco_packets_sent += connection->num_packets_sent;
620         }
621         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
622             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
623             return 0;
624         }
625         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
626     } else {
627         // implicit flow control -- TODO
628         int num_ready = 0;
629         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
630             hci_connection_t * connection = (hci_connection_t *) it;
631             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
632             if (connection->sco_tx_ready == 0) continue;
633             num_ready++;
634         }
635         return num_ready;
636     }
637 }
638 #endif
639 
640 // only used to send HCI Host Number Completed Packets
641 static int hci_can_send_comand_packet_transport(void){
642     if (hci_stack->hci_packet_buffer_reserved) return 0;
643 
644     // check for async hci transport implementations
645     if (hci_stack->hci_transport->can_send_packet_now){
646         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
647             return 0;
648         }
649     }
650     return 1;
651 }
652 
653 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
654 bool hci_can_send_command_packet_now(void){
655     if (hci_can_send_comand_packet_transport() == 0) return false;
656     return hci_stack->num_cmd_packets > 0u;
657 }
658 
659 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
660     // check for async hci transport implementations
661     if (!hci_stack->hci_transport->can_send_packet_now) return true;
662     return hci_stack->hci_transport->can_send_packet_now(packet_type);
663 }
664 
665 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
666     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
667     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
668 }
669 
670 bool hci_can_send_acl_le_packet_now(void){
671     if (hci_stack->hci_packet_buffer_reserved) return false;
672     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
673 }
674 
675 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
676     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
677     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
678 }
679 
680 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
681     if (hci_stack->hci_packet_buffer_reserved) return false;
682     return hci_can_send_prepared_acl_packet_now(con_handle);
683 }
684 
685 #ifdef ENABLE_CLASSIC
686 bool hci_can_send_acl_classic_packet_now(void){
687     if (hci_stack->hci_packet_buffer_reserved) return false;
688     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
689 }
690 
691 bool hci_can_send_prepared_sco_packet_now(void){
692     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
693     if (hci_have_usb_transport()){
694         return hci_stack->sco_can_send_now;
695     } else {
696         return hci_number_free_sco_slots() > 0;
697     }
698 }
699 
700 bool hci_can_send_sco_packet_now(void){
701     if (hci_stack->hci_packet_buffer_reserved) return false;
702     return hci_can_send_prepared_sco_packet_now();
703 }
704 
705 void hci_request_sco_can_send_now_event(void){
706     hci_stack->sco_waiting_for_can_send_now = 1;
707     hci_notify_if_sco_can_send_now();
708 }
709 #endif
710 
711 // used for internal checks in l2cap.c
712 bool hci_is_packet_buffer_reserved(void){
713     return hci_stack->hci_packet_buffer_reserved;
714 }
715 
716 // reserves outgoing packet buffer.
717 // @return 1 if successful
718 bool hci_reserve_packet_buffer(void){
719     if (hci_stack->hci_packet_buffer_reserved) {
720         log_error("hci_reserve_packet_buffer called but buffer already reserved");
721         return false;
722     }
723     hci_stack->hci_packet_buffer_reserved = true;
724     return true;
725 }
726 
727 void hci_release_packet_buffer(void){
728     hci_stack->hci_packet_buffer_reserved = false;
729 }
730 
731 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
732 static int hci_transport_synchronous(void){
733     return hci_stack->hci_transport->can_send_packet_now == NULL;
734 }
735 
736 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
737 
738     // 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);
739 
740     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
741     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
742     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
743         max_acl_data_packet_length = hci_stack->le_data_packets_length;
744     }
745 
746 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
747     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
748         max_acl_data_packet_length = connection->le_max_tx_octets;
749     }
750 #endif
751 
752     log_debug("hci_send_acl_packet_fragments entered");
753 
754     uint8_t status = ERROR_CODE_SUCCESS;
755     // multiple packets could be send on a synchronous HCI transport
756     while (true){
757 
758         log_debug("hci_send_acl_packet_fragments loop entered");
759 
760         // get current data
761         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
762         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
763         bool more_fragments = false;
764 
765         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
766         if (current_acl_data_packet_length > max_acl_data_packet_length){
767             more_fragments = true;
768             current_acl_data_packet_length = max_acl_data_packet_length;
769         }
770 
771         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
772         if (acl_header_pos > 0u){
773             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
774             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
775             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
776         }
777 
778         // update header len
779         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
780 
781         // count packet
782         connection->num_packets_sent++;
783         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
784 
785         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
786         if (more_fragments){
787             // update start of next fragment to send
788             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
789         } else {
790             // done
791             hci_stack->acl_fragmentation_pos = 0;
792             hci_stack->acl_fragmentation_total_size = 0;
793         }
794 
795         // send packet
796         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
797         const int size = current_acl_data_packet_length + 4;
798         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
799         hci_stack->acl_fragmentation_tx_active = 1;
800         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
801         if (err != 0){
802             // no error from HCI Transport expected
803             status = ERROR_CODE_HARDWARE_FAILURE;
804         }
805 
806         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
807 
808         // done yet?
809         if (!more_fragments) break;
810 
811         // can send more?
812         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
813     }
814 
815     log_debug("hci_send_acl_packet_fragments loop over");
816 
817     // release buffer now for synchronous transport
818     if (hci_transport_synchronous()){
819         hci_stack->acl_fragmentation_tx_active = 0;
820         hci_release_packet_buffer();
821         hci_emit_transport_packet_sent();
822     }
823 
824     return status;
825 }
826 
827 // pre: caller has reserved the packet buffer
828 uint8_t hci_send_acl_packet_buffer(int size){
829     btstack_assert(hci_stack->hci_packet_buffer_reserved);
830 
831     uint8_t * packet = hci_stack->hci_packet_buffer;
832     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
833 
834     // check for free places on Bluetooth module
835     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
836         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
837         hci_release_packet_buffer();
838         hci_emit_transport_packet_sent();
839         return BTSTACK_ACL_BUFFERS_FULL;
840     }
841 
842     hci_connection_t *connection = hci_connection_for_handle( con_handle);
843     if (!connection) {
844         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
845         hci_release_packet_buffer();
846         hci_emit_transport_packet_sent();
847         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
848     }
849 
850 #ifdef ENABLE_CLASSIC
851     hci_connection_timestamp(connection);
852 #endif
853 
854     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
855 
856     // setup data
857     hci_stack->acl_fragmentation_total_size = size;
858     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
859 
860     return hci_send_acl_packet_fragments(connection);
861 }
862 
863 #ifdef ENABLE_CLASSIC
864 // pre: caller has reserved the packet buffer
865 uint8_t hci_send_sco_packet_buffer(int size){
866     btstack_assert(hci_stack->hci_packet_buffer_reserved);
867 
868     uint8_t * packet = hci_stack->hci_packet_buffer;
869 
870     // skip checks in loopback mode
871     if (!hci_stack->loopback_mode){
872         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
873 
874         // check for free places on Bluetooth module
875         if (!hci_can_send_prepared_sco_packet_now()) {
876             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
877             hci_release_packet_buffer();
878             hci_emit_transport_packet_sent();
879             return BTSTACK_ACL_BUFFERS_FULL;
880         }
881 
882         // track send packet in connection struct
883         hci_connection_t *connection = hci_connection_for_handle( con_handle);
884         if (!connection) {
885             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
886             hci_release_packet_buffer();
887             hci_emit_transport_packet_sent();
888             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
889         }
890 
891         if (hci_have_usb_transport()){
892             // token used
893             hci_stack->sco_can_send_now = false;
894         } else {
895             if (hci_stack->synchronous_flow_control_enabled){
896                 connection->num_packets_sent++;
897             } else {
898                 connection->sco_tx_ready--;
899             }
900         }
901     }
902 
903     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
904 
905 #ifdef HAVE_SCO_TRANSPORT
906     hci_stack->sco_transport->send_packet(packet, size);
907     hci_release_packet_buffer();
908     hci_emit_transport_packet_sent();
909 
910     return 0;
911 #else
912     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
913     if (hci_transport_synchronous()){
914         hci_release_packet_buffer();
915         hci_emit_transport_packet_sent();
916     }
917 
918     if (err != 0){
919         return ERROR_CODE_HARDWARE_FAILURE;
920     }
921     return ERROR_CODE_SUCCESS;
922 #endif
923 }
924 #endif
925 
926 static void acl_handler(uint8_t *packet, uint16_t size){
927 
928     // get info
929     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
930     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
931     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
932     uint16_t acl_length         = READ_ACL_LENGTH(packet);
933 
934     // ignore non-registered handle
935     if (!conn){
936         log_error("acl_handler called with non-registered handle %u!" , con_handle);
937         return;
938     }
939 
940     // assert packet is complete
941     if ((acl_length + 4u) != size){
942         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
943         return;
944     }
945 
946 #ifdef ENABLE_CLASSIC
947     // update idle timestamp
948     hci_connection_timestamp(conn);
949 #endif
950 
951 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
952     hci_stack->host_completed_packets = 1;
953     conn->num_packets_completed++;
954 #endif
955 
956     // handle different packet types
957     switch (acl_flags & 0x03u) {
958 
959         case 0x01: // continuation fragment
960 
961             // sanity checks
962             if (conn->acl_recombination_pos == 0u) {
963                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
964                 return;
965             }
966             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
967                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
968                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
969                 conn->acl_recombination_pos = 0;
970                 return;
971             }
972 
973             // append fragment payload (header already stored)
974             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
975                          &packet[4], acl_length);
976             conn->acl_recombination_pos += acl_length;
977 
978             // forward complete L2CAP packet if complete.
979             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
980                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
981                 // reset recombination buffer
982                 conn->acl_recombination_length = 0;
983                 conn->acl_recombination_pos = 0;
984             }
985             break;
986 
987         case 0x02: { // first fragment
988 
989             // sanity check
990             if (conn->acl_recombination_pos) {
991                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
992                 conn->acl_recombination_pos = 0;
993             }
994 
995             // peek into L2CAP packet!
996             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
997 
998             // compare fragment size to L2CAP packet size
999             if (acl_length >= (l2cap_length + 4u)){
1000                 // forward fragment as L2CAP packet
1001                 hci_emit_acl_packet(packet, acl_length + 4u);
1002             } else {
1003 
1004                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1005                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1006                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1007                     return;
1008                 }
1009 
1010                 // store first fragment and tweak acl length for complete package
1011                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1012                              packet, acl_length + 4u);
1013                 conn->acl_recombination_pos    = acl_length + 4u;
1014                 conn->acl_recombination_length = l2cap_length;
1015                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1016             }
1017             break;
1018 
1019         }
1020         default:
1021             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1022             return;
1023     }
1024 
1025     // execute main loop
1026     hci_run();
1027 }
1028 
1029 static void hci_connection_stop_timer(hci_connection_t * conn){
1030     btstack_run_loop_remove_timer(&conn->timeout);
1031 #ifdef ENABLE_CLASSIC
1032     btstack_run_loop_remove_timer(&conn->timeout_sco);
1033 #endif
1034 }
1035 
1036 static void hci_shutdown_connection(hci_connection_t *conn){
1037     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1038 
1039 #ifdef ENABLE_CLASSIC
1040 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1041     bd_addr_type_t addr_type = conn->address_type;
1042 #endif
1043 #ifdef HAVE_SCO_TRANSPORT
1044     hci_con_handle_t con_handle = conn->con_handle;
1045 #endif
1046 #endif
1047 
1048     hci_connection_stop_timer(conn);
1049 
1050     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1051     btstack_memory_hci_connection_free( conn );
1052 
1053     // now it's gone
1054     hci_emit_nr_connections_changed();
1055 
1056 #ifdef ENABLE_CLASSIC
1057 #ifdef ENABLE_SCO_OVER_HCI
1058     // update SCO
1059     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1060         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1061     }
1062 #endif
1063 #ifdef HAVE_SCO_TRANSPORT
1064     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1065         hci_stack->sco_transport->close(con_handle);
1066     }
1067 #endif
1068 #endif
1069 }
1070 
1071 #ifdef ENABLE_CLASSIC
1072 
1073 static const uint16_t packet_type_sizes[] = {
1074     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1075     HCI_ACL_DH1_SIZE, 0, 0, 0,
1076     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1077     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1078 };
1079 static const uint8_t  packet_type_feature_requirement_bit[] = {
1080      0, // 3 slot packets
1081      1, // 5 slot packets
1082     25, // EDR 2 mpbs
1083     26, // EDR 3 mbps
1084     39, // 3 slot EDR packts
1085     40, // 5 slot EDR packet
1086 };
1087 static const uint16_t packet_type_feature_packet_mask[] = {
1088     0x0f00, // 3 slot packets
1089     0xf000, // 5 slot packets
1090     0x1102, // EDR 2 mpbs
1091     0x2204, // EDR 3 mbps
1092     0x0300, // 3 slot EDR packts
1093     0x3000, // 5 slot EDR packet
1094 };
1095 
1096 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1097     // enable packet types based on size
1098     uint16_t packet_types = 0;
1099     unsigned int i;
1100     for (i=0;i<16;i++){
1101         if (packet_type_sizes[i] == 0) continue;
1102         if (packet_type_sizes[i] <= buffer_size){
1103             packet_types |= 1 << i;
1104         }
1105     }
1106     // disable packet types due to missing local supported features
1107     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1108         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1109         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1110         if (feature_set) continue;
1111         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1112         packet_types &= ~packet_type_feature_packet_mask[i];
1113     }
1114     // flip bits for "may not be used"
1115     packet_types ^= 0x3306;
1116     return packet_types;
1117 }
1118 
1119 uint16_t hci_usable_acl_packet_types(void){
1120     return hci_stack->packet_types;
1121 }
1122 #endif
1123 
1124 uint8_t* hci_get_outgoing_packet_buffer(void){
1125     // hci packet buffer is >= acl data packet length
1126     return hci_stack->hci_packet_buffer;
1127 }
1128 
1129 uint16_t hci_max_acl_data_packet_length(void){
1130     return hci_stack->acl_data_packet_length;
1131 }
1132 
1133 #ifdef ENABLE_CLASSIC
1134 bool hci_extended_sco_link_supported(void){
1135     // No. 31, byte 3, bit 7
1136     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1137 }
1138 #endif
1139 
1140 bool hci_non_flushable_packet_boundary_flag_supported(void){
1141     // No. 54, byte 6, bit 6
1142     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1143 }
1144 
1145 #ifdef ENABLE_CLASSIC
1146 static int gap_ssp_supported(void){
1147     // No. 51, byte 6, bit 3
1148     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1149 }
1150 #endif
1151 
1152 static int hci_classic_supported(void){
1153 #ifdef ENABLE_CLASSIC
1154     // No. 37, byte 4, bit 5, = No BR/EDR Support
1155     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1156 #else
1157     return 0;
1158 #endif
1159 }
1160 
1161 static int hci_le_supported(void){
1162 #ifdef ENABLE_BLE
1163     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1164     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1165 #else
1166     return 0;
1167 #endif
1168 }
1169 
1170 #ifdef ENABLE_BLE
1171 
1172 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1173     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1174         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1175     } else {
1176         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1177     }
1178 }
1179 
1180 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1181     *addr_type = hci_stack->le_own_addr_type;
1182     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1183 }
1184 
1185 #ifdef ENABLE_LE_PERIPHERAL
1186 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1187     *addr_type = hci_stack->le_advertisements_own_addr_type;
1188     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1189 };
1190 #endif
1191 
1192 #ifdef ENABLE_LE_CENTRAL
1193 
1194 /**
1195  * @brief Get own addr type and address used for LE connections (Central)
1196  */
1197 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1198     *addr_type = hci_stack->le_connection_own_addr_type;
1199     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1200 }
1201 
1202 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1203 
1204     int offset = 3;
1205     int num_reports = packet[offset];
1206     offset += 1;
1207 
1208     int i;
1209     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1210     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1211     for (i=0; (i<num_reports) && (offset < size);i++){
1212         // sanity checks on data_length:
1213         uint8_t data_length = packet[offset + 8];
1214         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1215         if ((offset + 9u + data_length + 1u) > size)    return;
1216         // setup event
1217         uint8_t event_size = 10u + data_length;
1218         int pos = 0;
1219         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1220         event[pos++] = event_size;
1221         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1222         offset += 8;
1223         pos += 8;
1224         event[pos++] = packet[offset + 1 + data_length]; // rssi
1225         event[pos++] = data_length;
1226         offset++;
1227         (void)memcpy(&event[pos], &packet[offset], data_length);
1228         pos +=    data_length;
1229         offset += data_length + 1u; // rssi
1230         hci_emit_event(event, pos, 1);
1231     }
1232 }
1233 #endif
1234 #endif
1235 
1236 #ifdef ENABLE_BLE
1237 #ifdef ENABLE_LE_PERIPHERAL
1238 static void hci_update_advertisements_enabled_for_current_roles(void){
1239     if (hci_stack->le_advertisements_enabled){
1240         // get number of active le slave connections
1241         int num_slave_connections = 0;
1242         btstack_linked_list_iterator_t it;
1243         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1244         while (btstack_linked_list_iterator_has_next(&it)){
1245             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1246             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1247             if (con->state != OPEN) continue;
1248             if (con->role  != HCI_ROLE_SLAVE) continue;
1249             if (!hci_is_le_connection(con)) continue;
1250             num_slave_connections++;
1251         }
1252         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1253         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1254     } else {
1255         hci_stack->le_advertisements_enabled_for_current_roles = false;
1256     }
1257 }
1258 #endif
1259 #endif
1260 
1261 #ifdef ENABLE_CLASSIC
1262 static void gap_run_set_local_name(void){
1263     hci_reserve_packet_buffer();
1264     uint8_t * packet = hci_stack->hci_packet_buffer;
1265     // construct HCI Command and send
1266     uint16_t opcode = hci_write_local_name.opcode;
1267     hci_stack->last_cmd_opcode = opcode;
1268     packet[0] = opcode & 0xff;
1269     packet[1] = opcode >> 8;
1270     packet[2] = DEVICE_NAME_LEN;
1271     memset(&packet[3], 0, DEVICE_NAME_LEN);
1272     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1273     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1274     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1275     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1276     // expand '00:00:00:00:00:00' in name with bd_addr
1277     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1278     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1279 }
1280 
1281 static void gap_run_set_eir_data(void){
1282     hci_reserve_packet_buffer();
1283     uint8_t * packet = hci_stack->hci_packet_buffer;
1284     // construct HCI Command in-place and send
1285     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1286     hci_stack->last_cmd_opcode = opcode;
1287     uint16_t offset = 0;
1288     packet[offset++] = opcode & 0xff;
1289     packet[offset++] = opcode >> 8;
1290     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1291     packet[offset++] = 0;  // FEC not required
1292     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1293     if (hci_stack->eir_data){
1294         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1295         ad_context_t context;
1296         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1297             uint8_t data_type   = ad_iterator_get_data_type(&context);
1298             uint8_t size        = ad_iterator_get_data_len(&context);
1299             const uint8_t *data = ad_iterator_get_data(&context);
1300             // copy item
1301             packet[offset++] = size + 1;
1302             packet[offset++] = data_type;
1303             memcpy(&packet[offset], data, size);
1304             // update name item
1305             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1306                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1307             }
1308             offset += size;
1309         }
1310     } else {
1311         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1312         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1313         packet[offset++] = bytes_to_copy + 1;
1314         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1315         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1316         // expand '00:00:00:00:00:00' in name with bd_addr
1317         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1318     }
1319     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1320 }
1321 
1322 static void hci_run_gap_tasks_classic(void){
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1325         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1330         gap_run_set_local_name();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1335         gap_run_set_eir_data();
1336         return;
1337     }
1338     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1339         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1340         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1341         return;
1342     }
1343     // write page scan activity
1344     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1345         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1346         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1347         return;
1348     }
1349     // write page scan type
1350     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1351         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1352         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1353         return;
1354     }
1355     // write page timeout
1356     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_TIMEOUT) != 0) {
1357         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_TIMEOUT;
1358         hci_send_cmd(&hci_write_page_timeout, hci_stack->page_timeout);
1359         return;
1360     }
1361     // send scan enable
1362     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1363         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1364         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1365         return;
1366     }
1367     // send write scan activity
1368     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY) != 0) {
1369         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
1370         hci_send_cmd(&hci_write_inquiry_scan_activity, hci_stack->inquiry_scan_interval, hci_stack->inquiry_scan_window);
1371         return;
1372     }
1373 }
1374 #endif
1375 
1376 #ifndef HAVE_HOST_CONTROLLER_API
1377 
1378 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1379     if (!hci_stack->config) return 0;
1380     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1381     // Limit baud rate for Broadcom chipsets to 3 mbps
1382     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1383         baud_rate = 3000000;
1384     }
1385     return baud_rate;
1386 }
1387 
1388 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1389     UNUSED(ds);
1390 
1391     switch (hci_stack->substate){
1392         case HCI_INIT_W4_SEND_RESET:
1393             log_info("Resend HCI Reset");
1394             hci_stack->substate = HCI_INIT_SEND_RESET;
1395             hci_stack->num_cmd_packets = 1;
1396             hci_run();
1397             break;
1398         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1399             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1400             if (hci_stack->hci_transport->reset_link){
1401                 hci_stack->hci_transport->reset_link();
1402             }
1403 
1404             /* fall through */
1405 
1406         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1407             log_info("Resend HCI Reset - CSR Warm Boot");
1408             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1409             hci_stack->num_cmd_packets = 1;
1410             hci_run();
1411             break;
1412         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1413             if (hci_stack->hci_transport->set_baudrate){
1414                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1415                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1416                 hci_stack->hci_transport->set_baudrate(baud_rate);
1417             }
1418             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1419             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1420                 if (hci_stack->hci_transport->reset_link){
1421                     log_info("Link Reset");
1422                     hci_stack->hci_transport->reset_link();
1423                 }
1424                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1425                 hci_run();
1426             }
1427             break;
1428         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1429             // otherwise continue
1430             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1431             hci_send_cmd(&hci_read_local_supported_commands);
1432             break;
1433         default:
1434             break;
1435     }
1436 }
1437 #endif
1438 
1439 static void hci_initializing_next_state(void){
1440     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1441 }
1442 
1443 static void hci_init_done(void){
1444     // done. tell the app
1445     log_info("hci_init_done -> HCI_STATE_WORKING");
1446     hci_stack->state = HCI_STATE_WORKING;
1447     hci_emit_state();
1448 }
1449 
1450 // assumption: hci_can_send_command_packet_now() == true
1451 static void hci_initializing_run(void){
1452     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1453 
1454     if (!hci_can_send_command_packet_now()) return;
1455 
1456 #ifndef HAVE_HOST_CONTROLLER_API
1457     bool need_baud_change = hci_stack->config
1458             && hci_stack->chipset
1459             && hci_stack->chipset->set_baudrate_command
1460             && hci_stack->hci_transport->set_baudrate
1461             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1462 #endif
1463 
1464     switch (hci_stack->substate){
1465         case HCI_INIT_SEND_RESET:
1466             hci_state_reset();
1467 
1468 #ifndef HAVE_HOST_CONTROLLER_API
1469             // prepare reset if command complete not received in 100ms
1470             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1471             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1472             btstack_run_loop_add_timer(&hci_stack->timeout);
1473 #endif
1474             // send command
1475             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1476             hci_send_cmd(&hci_reset);
1477             break;
1478         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1479             hci_send_cmd(&hci_read_local_version_information);
1480             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1481             break;
1482 
1483 #ifndef HAVE_HOST_CONTROLLER_API
1484         case HCI_INIT_SEND_READ_LOCAL_NAME:
1485             hci_send_cmd(&hci_read_local_name);
1486             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1487             break;
1488         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1489             hci_state_reset();
1490             // prepare reset if command complete not received in 100ms
1491             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1492             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1493             btstack_run_loop_add_timer(&hci_stack->timeout);
1494             // send command
1495             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1496             hci_send_cmd(&hci_reset);
1497             break;
1498         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1499             hci_state_reset();
1500             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1501             hci_send_cmd(&hci_reset);
1502             break;
1503         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1504             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1505             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1506             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1507             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1508             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1509             break;
1510         }
1511         case HCI_INIT_SET_BD_ADDR:
1512             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1513             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1514             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1515             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1516             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1517             break;
1518         case HCI_INIT_SEND_BAUD_CHANGE:
1519             if (need_baud_change) {
1520                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1521                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1522                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1523                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1524                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1525                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1526                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1527                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1528                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1529                     btstack_run_loop_add_timer(&hci_stack->timeout);
1530                }
1531                break;
1532             }
1533 
1534             /* fall through */
1535 
1536         case HCI_INIT_CUSTOM_INIT:
1537             // Custom initialization
1538             if (hci_stack->chipset && hci_stack->chipset->next_command){
1539                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1540                 bool send_cmd = false;
1541                 switch (hci_stack->chipset_result){
1542                     case BTSTACK_CHIPSET_VALID_COMMAND:
1543                         send_cmd = true;
1544                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1545                         break;
1546                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1547                         send_cmd = true;
1548                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1549                         log_info("CSR Warm Boot");
1550                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1551                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1552                         btstack_run_loop_add_timer(&hci_stack->timeout);
1553                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1554                             && hci_stack->config
1555                             && hci_stack->chipset
1556                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1557                             && hci_stack->hci_transport->set_baudrate
1558                             && hci_transport_uart_get_main_baud_rate()){
1559                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1560                         } else {
1561                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1562                         }
1563                         break;
1564                     default:
1565                         break;
1566                 }
1567 
1568                 if (send_cmd){
1569                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1570                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1571                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1572                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1573                     break;
1574                 }
1575                 log_info("Init script done");
1576 
1577                 // Init script download on Broadcom chipsets causes:
1578                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1579                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1580                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1581 
1582                     // - baud rate to reset, restore UART baud rate if needed
1583                     if (need_baud_change) {
1584                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1585                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1586                         hci_stack->hci_transport->set_baudrate(baud_rate);
1587                     }
1588 
1589                     uint16_t bcm_delay_ms = 300;
1590                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1591                     //   -> Work around: wait here.
1592                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1593                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1594                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1595                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1596                     btstack_run_loop_add_timer(&hci_stack->timeout);
1597                     break;
1598                 }
1599             }
1600 #endif
1601             /* fall through */
1602 
1603         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1604             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1605             hci_send_cmd(&hci_read_local_supported_commands);
1606             break;
1607         case HCI_INIT_READ_BD_ADDR:
1608             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1609             hci_send_cmd(&hci_read_bd_addr);
1610             break;
1611         case HCI_INIT_READ_BUFFER_SIZE:
1612             // only read buffer size if supported
1613             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1614                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1615                 hci_send_cmd(&hci_read_buffer_size);
1616                 break;
1617             }
1618 
1619             /* fall through */
1620 
1621         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1622             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1623             hci_send_cmd(&hci_read_local_supported_features);
1624             break;
1625 
1626 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1627         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1628             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1629             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1630             break;
1631         case HCI_INIT_HOST_BUFFER_SIZE:
1632             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1633             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1634                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1635             break;
1636 #endif
1637 
1638         case HCI_INIT_SET_EVENT_MASK:
1639             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1640             if (hci_le_supported()){
1641                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1642             } else {
1643                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1644                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1645             }
1646             break;
1647 
1648 #ifdef ENABLE_CLASSIC
1649         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1650             if (hci_classic_supported() && gap_ssp_supported()){
1651                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1652                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1653                 break;
1654             }
1655 
1656             /* fall through */
1657 
1658         case HCI_INIT_WRITE_INQUIRY_MODE:
1659             if (hci_classic_supported()){
1660                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1661                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1662                 break;
1663             }
1664 
1665             /* fall through */
1666 
1667         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1668             // skip write secure connections host support if not supported or disabled
1669             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1670                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1671                 hci_stack->secure_connections_active = true;
1672                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1673                 break;
1674             }
1675 
1676 #ifdef ENABLE_SCO_OVER_HCI
1677             /* fall through */
1678 
1679         // only sent if ENABLE_SCO_OVER_HCI is defined
1680         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1681             // skip write synchronous flow control if not supported
1682             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1683                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1684                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1685                 break;
1686             }
1687             /* fall through */
1688 
1689         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1690             // skip write default erroneous data reporting if not supported
1691             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1692                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1693                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1694                 break;
1695             }
1696 #endif
1697 
1698 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1699             /* fall through */
1700 
1701         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1702         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1703             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1704                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1705 #ifdef ENABLE_SCO_OVER_HCI
1706                 log_info("BCM: Route SCO data via HCI transport");
1707                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1708 #endif
1709 #ifdef ENABLE_SCO_OVER_PCM
1710                 log_info("BCM: Route SCO data via PCM interface");
1711 #ifdef ENABLE_BCM_PCM_WBS
1712                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1713                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1714 #else
1715                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1716                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1717 #endif
1718 #endif
1719                 break;
1720             }
1721 #endif
1722 
1723 #ifdef ENABLE_SCO_OVER_PCM
1724             /* fall through */
1725 
1726         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1727             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1728                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1729                 log_info("BCM: Config PCM interface for I2S");
1730 #ifdef ENABLE_BCM_PCM_WBS
1731                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1732                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1733 #else
1734                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1735                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1736 #endif
1737                 break;
1738             }
1739 #endif
1740 #endif
1741 
1742 #ifdef ENABLE_BLE
1743             /* fall through */
1744 
1745         // LE INIT
1746         case HCI_INIT_LE_READ_BUFFER_SIZE:
1747             if (hci_le_supported()){
1748                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1749                 hci_send_cmd(&hci_le_read_buffer_size);
1750                 break;
1751             }
1752 
1753             /* fall through */
1754 
1755         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1756             // skip write le host if not supported (e.g. on LE only EM9301)
1757             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1758                 // LE Supported Host = 1, Simultaneous Host = 0
1759                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1760                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1761                 break;
1762             }
1763 
1764             /* fall through */
1765 
1766         case HCI_INIT_LE_SET_EVENT_MASK:
1767             if (hci_le_supported()){
1768                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1769                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1770                 break;
1771             }
1772 #endif
1773 
1774 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1775             /* fall through */
1776 
1777         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1778             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1779                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1780                 hci_send_cmd(&hci_le_read_maximum_data_length);
1781                 break;
1782             }
1783 
1784             /* fall through */
1785 
1786         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1787             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1788                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1789                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1790                 break;
1791             }
1792 #endif
1793 
1794 #ifdef ENABLE_LE_CENTRAL
1795             /* fall through */
1796 
1797         case HCI_INIT_READ_WHITE_LIST_SIZE:
1798             if (hci_le_supported()){
1799                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1800                 hci_send_cmd(&hci_le_read_white_list_size);
1801                 break;
1802             }
1803 
1804             /* fall through */
1805 
1806         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1807             if (hci_le_supported()){
1808                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1809                 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);
1810                 break;
1811             }
1812 #endif
1813 
1814             /* fall through */
1815 
1816         case HCI_INIT_DONE:
1817             hci_stack->substate = HCI_INIT_DONE;
1818 #ifdef ENABLE_CLASSIC
1819             // init sequence complete, check if GAP Tasks are completed
1820             if (hci_stack->gap_tasks != 0) {
1821                 hci_run_gap_tasks_classic();
1822                 break;
1823             }
1824 #endif
1825             hci_init_done();
1826             break;
1827 
1828         default:
1829             return;
1830     }
1831 }
1832 
1833 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1834     bool command_completed = false;
1835     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1836         uint16_t opcode = little_endian_read_16(packet,3);
1837         if (opcode == hci_stack->last_cmd_opcode){
1838             command_completed = true;
1839             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1840         } else {
1841             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1842         }
1843     }
1844 
1845     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1846         uint8_t  status = packet[2];
1847         uint16_t opcode = little_endian_read_16(packet,4);
1848         if (opcode == hci_stack->last_cmd_opcode){
1849             if (status){
1850                 command_completed = true;
1851                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1852             } else {
1853                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1854             }
1855         } else {
1856             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1857         }
1858     }
1859 #ifndef HAVE_HOST_CONTROLLER_API
1860     // Vendor == CSR
1861     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1862         // TODO: track actual command
1863         command_completed = true;
1864     }
1865 
1866     // Vendor == Toshiba
1867     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1868         // TODO: track actual command
1869         command_completed = true;
1870         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1871         hci_stack->num_cmd_packets = 1;
1872     }
1873 #endif
1874 
1875     return command_completed;
1876 }
1877 
1878 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1879 
1880     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1881 
1882     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1883 
1884 #ifndef HAVE_HOST_CONTROLLER_API
1885 
1886     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1887     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1888     //
1889     // HCI Reset
1890     // Timeout 100 ms
1891     // HCI Reset
1892     // Command Complete Reset
1893     // HCI Read Local Version Information
1894     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1895     // hang...
1896     //
1897     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1898     if (!command_completed
1899             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1900             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1901 
1902         uint16_t opcode = little_endian_read_16(packet,3);
1903         if (opcode == hci_reset.opcode){
1904             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1905             return;
1906         }
1907     }
1908 
1909     // CSR & H5
1910     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1911     if (!command_completed
1912             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1913             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1914 
1915         uint16_t opcode = little_endian_read_16(packet,3);
1916         if (opcode == hci_reset.opcode){
1917             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1918             return;
1919         }
1920     }
1921 
1922     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1923     // fix: Correct substate and behave as command below
1924     if (command_completed){
1925         switch (hci_stack->substate){
1926             case HCI_INIT_SEND_RESET:
1927                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1928                 break;
1929             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1930                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1931                 break;
1932             default:
1933                 break;
1934         }
1935     }
1936 
1937 #endif
1938 
1939     if (!command_completed) return;
1940 
1941     bool need_baud_change = false;
1942     bool need_addr_change = false;
1943 
1944 #ifndef HAVE_HOST_CONTROLLER_API
1945     need_baud_change = hci_stack->config
1946                         && hci_stack->chipset
1947                         && hci_stack->chipset->set_baudrate_command
1948                         && hci_stack->hci_transport->set_baudrate
1949                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1950 
1951     need_addr_change = hci_stack->custom_bd_addr_set
1952                         && hci_stack->chipset
1953                         && hci_stack->chipset->set_bd_addr_command;
1954 #endif
1955 
1956     switch(hci_stack->substate){
1957 
1958 #ifndef HAVE_HOST_CONTROLLER_API
1959         case HCI_INIT_SEND_RESET:
1960             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1961             // fix: just correct substate and behave as command below
1962 
1963             /* fall through */
1964 #endif
1965 
1966         case HCI_INIT_W4_SEND_RESET:
1967             btstack_run_loop_remove_timer(&hci_stack->timeout);
1968             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1969             return;
1970 
1971 #ifndef HAVE_HOST_CONTROLLER_API
1972         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1973             // for STLC2500D, baud rate change already happened.
1974             // for others, baud rate gets changed now
1975             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1976                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1977                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1978                 hci_stack->hci_transport->set_baudrate(baud_rate);
1979             }
1980             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1981             return;
1982         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1983             btstack_run_loop_remove_timer(&hci_stack->timeout);
1984             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1985             return;
1986         case HCI_INIT_W4_CUSTOM_INIT:
1987             // repeat custom init
1988             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1989             return;
1990 #endif
1991 
1992         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1993             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1994               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1995                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1996                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1997                 return;
1998             }
1999             if (need_addr_change){
2000                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2001                 return;
2002             }
2003             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2004             return;
2005 #ifndef HAVE_HOST_CONTROLLER_API
2006         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
2007             if (need_baud_change){
2008                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
2009                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
2010                 hci_stack->hci_transport->set_baudrate(baud_rate);
2011             }
2012             if (need_addr_change){
2013                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2014                 return;
2015             }
2016             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2017             return;
2018         case HCI_INIT_W4_SET_BD_ADDR:
2019             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
2020             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
2021             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2022                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2023                 return;
2024             }
2025             // skipping st warm boot
2026             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2027             return;
2028         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2029             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2030             return;
2031 #endif
2032 
2033         case HCI_INIT_DONE:
2034             // set state if we came here by fall through
2035             hci_stack->substate = HCI_INIT_DONE;
2036             return;
2037 
2038         default:
2039             break;
2040     }
2041     hci_initializing_next_state();
2042 }
2043 
2044 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2045     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2046     bd_addr_t bd_address;
2047     (void)memcpy(&bd_address, conn->address, 6);
2048 
2049 #ifdef ENABLE_CLASSIC
2050     // cache needed data
2051     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2052 #endif
2053 
2054     // connection failed, remove entry
2055     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2056     btstack_memory_hci_connection_free( conn );
2057 
2058 #ifdef ENABLE_CLASSIC
2059     // notify client if dedicated bonding
2060     if (notify_dedicated_bonding_failed){
2061         log_info("hci notify_dedicated_bonding_failed");
2062         hci_emit_dedicated_bonding_result(bd_address, status);
2063     }
2064 
2065     // if authentication error, also delete link key
2066     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2067         gap_drop_link_key_for_bd_addr(bd_address);
2068     }
2069 #else
2070     UNUSED(status);
2071 #endif
2072 }
2073 
2074 #ifdef ENABLE_CLASSIC
2075 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2076     // SSP Controller
2077     if (features[6] & (1 << 3)){
2078         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2079     }
2080     // eSCO
2081     if (features[3] & (1<<7)){
2082         conn->remote_supported_features[0] |= 1;
2083     }
2084     // Extended features
2085     if (features[7] & (1<<7)){
2086         conn->remote_supported_features[0] |= 2;
2087     }
2088 }
2089 
2090 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2091     // SSP Host
2092     if (features[0] & (1 << 0)){
2093         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2094     }
2095     // SC Host
2096     if (features[0] & (1 << 3)){
2097         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2098     }
2099 }
2100 
2101 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2102     // SC Controller
2103     if (features[1] & (1 << 0)){
2104         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2105     }
2106 }
2107 
2108 static void hci_handle_remote_features_received(hci_connection_t * conn){
2109     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2110     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2111     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2112     if (conn->bonding_flags & BONDING_DEDICATED){
2113         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2114     }
2115 }
2116 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2117     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2118     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2119 }
2120 
2121 #endif
2122 
2123 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2124     // handle BT initialization
2125     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2126         hci_initializing_event_handler(packet, size);
2127     }
2128 
2129     // help with BT sleep
2130     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2131         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2132         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2133         hci_initializing_next_state();
2134     }
2135 }
2136 
2137 #ifdef ENABLE_CLASSIC
2138 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2139     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2140     conn->encryption_key_size = encryption_key_size;
2141 
2142     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2143         conn->requested_security_level = LEVEL_0;
2144         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2145         return;
2146     }
2147 
2148     // Request remote features if not already done
2149     hci_trigger_remote_features_for_connection(conn);
2150 
2151     // Request Authentication if not already done
2152     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2153     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2154 }
2155 #endif
2156 
2157 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2158     UNUSED(size);
2159 
2160     uint16_t manufacturer;
2161 #ifdef ENABLE_CLASSIC
2162     hci_con_handle_t handle;
2163     hci_connection_t * conn;
2164     uint8_t status;
2165 #endif
2166     // get num cmd packets - limit to 1 to reduce complexity
2167     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2168 
2169     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2170     switch (opcode){
2171         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2172             if (packet[5]) break;
2173             // terminate, name 248 chars
2174             packet[6+248] = 0;
2175             log_info("local name: %s", &packet[6]);
2176             break;
2177         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2178             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2179             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2180                 uint16_t acl_len = little_endian_read_16(packet, 6);
2181                 uint16_t sco_len = packet[8];
2182 
2183                 // determine usable ACL/SCO payload size
2184                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2185                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2186 
2187                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2188                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2189 
2190                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2191                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2192                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2193             }
2194             break;
2195         case HCI_OPCODE_HCI_READ_RSSI:
2196             if (packet[5] == ERROR_CODE_SUCCESS){
2197                 uint8_t event[5];
2198                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2199                 event[1] = 3;
2200                 (void)memcpy(&event[2], &packet[6], 3);
2201                 hci_emit_event(event, sizeof(event), 1);
2202             }
2203             break;
2204 #ifdef ENABLE_BLE
2205         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2206             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2207             hci_stack->le_acl_packets_total_num = packet[8];
2208             // determine usable ACL payload size
2209             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2210                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2211             }
2212             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2213             break;
2214 #endif
2215 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2216         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2217             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2218             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2219             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);
2220             break;
2221 #endif
2222 #ifdef ENABLE_LE_CENTRAL
2223         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2224             hci_stack->le_whitelist_capacity = packet[6];
2225             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2226             break;
2227 #endif
2228         case HCI_OPCODE_HCI_READ_BD_ADDR:
2229             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2230             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));
2231 #ifdef ENABLE_CLASSIC
2232             if (hci_stack->link_key_db){
2233                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2234             }
2235 #endif
2236             break;
2237 #ifdef ENABLE_CLASSIC
2238         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2239             hci_emit_discoverable_enabled(hci_stack->discoverable);
2240             break;
2241         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2242             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2243                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2244                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2245                 hci_emit_event(event, sizeof(event), 1);
2246             }
2247             break;
2248 #endif
2249         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2250             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2251 
2252 #ifdef ENABLE_CLASSIC
2253             // determine usable ACL packet types based on host buffer size and supported features
2254             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2255             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2256 #endif
2257             // Classic/LE
2258             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2259             break;
2260         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2261             manufacturer = little_endian_read_16(packet, 10);
2262             // map Cypress to Broadcom
2263             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2264                 log_info("Treat Cypress as Broadcom");
2265                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2266                 little_endian_store_16(packet, 10, manufacturer);
2267             }
2268             hci_stack->manufacturer = manufacturer;
2269             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2270             break;
2271         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2272             hci_stack->local_supported_commands[0] =
2273                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2274                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2275                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2276                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2277                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2278                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2279                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2280                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2281             hci_stack->local_supported_commands[1] =
2282                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2283                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2284                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2285                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2286                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2287             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2288             break;
2289 #ifdef ENABLE_CLASSIC
2290         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2291             if (packet[5]) return;
2292             hci_stack->synchronous_flow_control_enabled = 1;
2293             break;
2294         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2295             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2296             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2297             conn   = hci_connection_for_handle(handle);
2298             if (conn != NULL) {
2299                 uint8_t key_size = 0;
2300                 if (status == 0){
2301                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2302                     log_info("Handle %04x key Size: %u", handle, key_size);
2303                 } else {
2304                     key_size = 1;
2305                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2306                 }
2307                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2308             }
2309             break;
2310         // assert pairing complete event is emitted.
2311         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2312         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2313         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2314         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2315             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2316             // lookup connection by gap pairing addr
2317             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2318             if (conn == NULL) break;
2319             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2320             break;
2321 
2322 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2323         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2324         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2325             uint8_t event[67];
2326             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2327             event[1] = 65;
2328             (void)memset(&event[2], 0, 65);
2329             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2330                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2331                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2332                     event[2] = 3;
2333                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2334                 } else {
2335                     event[2] = 1;
2336                 }
2337             }
2338             hci_emit_event(event, sizeof(event), 0);
2339             break;
2340         }
2341 
2342         // note: only needed if user does not provide OOB data
2343         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2344             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2345             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2346             if (conn == NULL) break;
2347             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2348             break;
2349 #endif
2350 #endif
2351         default:
2352             break;
2353     }
2354 }
2355 
2356 #ifdef ENABLE_BLE
2357 static void event_handle_le_connection_complete(const uint8_t * packet){
2358 	bd_addr_t addr;
2359 	bd_addr_type_t addr_type;
2360 	hci_connection_t * conn;
2361 
2362 	// Connection management
2363 	reverse_bd_addr(&packet[8], addr);
2364 	addr_type = (bd_addr_type_t)packet[7];
2365 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2366 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2367 
2368 #ifdef ENABLE_LE_CENTRAL
2369 	// handle error: error is reported only to the initiator -> outgoing connection
2370 	if (packet[3]){
2371 
2372 		// handle cancelled outgoing connection
2373 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2374 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2375 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2376 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2377 		    // reset state
2378             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2379             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2380 			// get outgoing connection conn struct for direct connect
2381 			conn = gap_get_outgoing_connection();
2382 		}
2383 
2384 		// outgoing le connection establishment is done
2385 		if (conn){
2386 			// remove entry
2387 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2388 			btstack_memory_hci_connection_free( conn );
2389 		}
2390 		return;
2391 	}
2392 #endif
2393 
2394 	// on success, both hosts receive connection complete event
2395 	if (packet[6] == HCI_ROLE_MASTER){
2396 #ifdef ENABLE_LE_CENTRAL
2397 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2398 		// note: no hci_connection_t object exists yet for connect with whitelist
2399 		if (hci_is_le_connection_type(addr_type)){
2400 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2401 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2402 		}
2403 #endif
2404 	} else {
2405 #ifdef ENABLE_LE_PERIPHERAL
2406 		// if we're slave, it was an incoming connection, advertisements have stopped
2407 		hci_stack->le_advertisements_active = false;
2408 #endif
2409 	}
2410 
2411 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2412 	if (!conn){
2413 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2414 	}
2415 
2416 	// no memory, sorry.
2417 	if (!conn){
2418 		return;
2419 	}
2420 
2421 	conn->state = OPEN;
2422 	conn->role  = packet[6];
2423 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2424 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2425 
2426 #ifdef ENABLE_LE_PERIPHERAL
2427 	if (packet[6] == HCI_ROLE_SLAVE){
2428 		hci_update_advertisements_enabled_for_current_roles();
2429 	}
2430 #endif
2431 
2432     // init unenhanced att bearer mtu
2433     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2434     conn->att_connection.mtu_exchanged = false;
2435 
2436     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2437 
2438 	// restart timer
2439 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2440 	// btstack_run_loop_add_timer(&conn->timeout);
2441 
2442 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2443 
2444 	hci_emit_nr_connections_changed();
2445 }
2446 #endif
2447 
2448 #ifdef ENABLE_CLASSIC
2449 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){
2450     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2451     // LEVEL_4 is tested by l2cap
2452     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2453     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2454     if (level >= LEVEL_3){
2455         // MITM not possible without keyboard or display
2456         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2457         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2458 
2459         // MITM possible if one side has keyboard and the other has keyboard or display
2460         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2461         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2462 
2463         // MITM not possible if one side has only display and other side has no keyboard
2464         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2465         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2466     }
2467     // LEVEL 2 requires SSP, which is a given
2468     return true;
2469 }
2470 
2471 static bool btstack_is_null(uint8_t * data, uint16_t size){
2472     uint16_t i;
2473     for (i=0; i < size ; i++){
2474         if (data[i] != 0) {
2475             return false;
2476         }
2477     }
2478     return true;
2479 }
2480 
2481 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2482     // get requested security level
2483     gap_security_level_t requested_security_level = conn->requested_security_level;
2484     if (hci_stack->gap_secure_connections_only_mode){
2485         requested_security_level = LEVEL_4;
2486     }
2487 
2488     // assess security: LEVEL 4 requires SC
2489     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2490     if ((requested_security_level == LEVEL_4) &&
2491         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2492         !hci_remote_sc_enabled(conn)){
2493         log_info("Level 4 required, but SC not supported -> abort");
2494         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2495         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2496         return;
2497     }
2498 
2499     // assess security based on io capabilities
2500     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2501         // responder: fully validate io caps of both sides as well as OOB data
2502         bool security_possible = false;
2503         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2504 
2505 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2506         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2507         // so we merge the OOB data availability
2508         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2509         if (conn->classic_oob_c_192 != NULL){
2510             have_oob_data |= 1;
2511         }
2512         if (conn->classic_oob_c_256 != NULL){
2513             have_oob_data |= 2;
2514         }
2515         // for up to Level 3, either P-192 as well as P-256 will do
2516         // 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
2517         // if remote does not SC, we should not receive P-256 data either
2518         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2519             security_possible = true;
2520         }
2521         // for Level 4, P-256 is needed
2522         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2523             security_possible = true;
2524         }
2525 #endif
2526 
2527         if (security_possible == false){
2528             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2529             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2530             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2531             return;
2532         }
2533     } else {
2534         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2535 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2536 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2537         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2538             log_info("Level 3+ required, but no input/output -> abort");
2539             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2540             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2541             return;
2542         }
2543 #endif
2544 #endif
2545     }
2546 
2547 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2548     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2549         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2550     } else {
2551         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2552     }
2553 #endif
2554 }
2555 
2556 #endif
2557 
2558 static void event_handler(uint8_t *packet, uint16_t size){
2559 
2560     uint16_t event_length = packet[1];
2561 
2562     // assert packet is complete
2563     if (size != (event_length + 2u)){
2564         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2565         return;
2566     }
2567 
2568     bd_addr_type_t addr_type;
2569     hci_con_handle_t handle;
2570     hci_connection_t * conn;
2571     int i;
2572     int create_connection_cmd;
2573 
2574 #ifdef ENABLE_CLASSIC
2575     hci_link_type_t link_type;
2576     bd_addr_t addr;
2577 #endif
2578 
2579     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2580 
2581     switch (hci_event_packet_get_type(packet)) {
2582 
2583         case HCI_EVENT_COMMAND_COMPLETE:
2584             handle_command_complete_event(packet, size);
2585             break;
2586 
2587         case HCI_EVENT_COMMAND_STATUS:
2588             // get num cmd packets - limit to 1 to reduce complexity
2589             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2590 
2591             // check command status to detected failed outgoing connections
2592             create_connection_cmd = 0;
2593 #ifdef ENABLE_CLASSIC
2594             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2595                 create_connection_cmd = 1;
2596             }
2597 #endif
2598 #ifdef ENABLE_LE_CENTRAL
2599             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2600                 create_connection_cmd = 1;
2601             }
2602 #endif
2603             if (create_connection_cmd) {
2604                 uint8_t status = hci_event_command_status_get_status(packet);
2605                 addr_type = hci_stack->outgoing_addr_type;
2606                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2607                 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);
2608 
2609                 // reset outgoing address info
2610                 memset(hci_stack->outgoing_addr, 0, 6);
2611                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2612 
2613                 // on error
2614                 if (status != ERROR_CODE_SUCCESS){
2615 #ifdef ENABLE_LE_CENTRAL
2616                     if (hci_is_le_connection_type(addr_type)){
2617                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2618                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2619                     }
2620 #endif
2621                     // error => outgoing connection failed
2622                     if (conn != NULL){
2623                         hci_handle_connection_failed(conn, status);
2624                     }
2625                 }
2626             }
2627 
2628 #ifdef ENABLE_CLASSIC
2629             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2630                 uint8_t status = hci_event_command_status_get_status(packet);
2631                 log_info("command status (inquiry), status %x", status);
2632                 if (status == ERROR_CODE_SUCCESS) {
2633                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2634                 } else {
2635                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2636                 }
2637             }
2638 #endif
2639             break;
2640 
2641         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2642             if (size < 3) return;
2643             uint16_t num_handles = packet[2];
2644             if (size != (3u + num_handles * 4u)) return;
2645             uint16_t offset = 3;
2646             for (i=0; i<num_handles;i++){
2647                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2648                 offset += 2u;
2649                 uint16_t num_packets = little_endian_read_16(packet, offset);
2650                 offset += 2u;
2651 
2652                 conn = hci_connection_for_handle(handle);
2653                 if (!conn){
2654                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2655                     continue;
2656                 }
2657 
2658                 if (conn->num_packets_sent >= num_packets){
2659                     conn->num_packets_sent -= num_packets;
2660                 } else {
2661                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2662                     conn->num_packets_sent = 0;
2663                 }
2664                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2665 
2666 #ifdef ENABLE_CLASSIC
2667                 // For SCO, we do the can_send_now_check here
2668                 hci_notify_if_sco_can_send_now();
2669 #endif
2670             }
2671             break;
2672         }
2673 
2674 #ifdef ENABLE_CLASSIC
2675         case HCI_EVENT_INQUIRY_COMPLETE:
2676             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2677                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2678                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2679                 hci_emit_event(event, sizeof(event), 1);
2680             }
2681             break;
2682         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2683             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2684                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2685             }
2686             break;
2687         case HCI_EVENT_CONNECTION_REQUEST:
2688             reverse_bd_addr(&packet[2], addr);
2689             link_type = (hci_link_type_t) packet[11];
2690 
2691             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2692             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2693                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2694                 bd_addr_copy(hci_stack->decline_addr, addr);
2695                 break;
2696             }
2697 
2698             if (hci_stack->gap_classic_accept_callback != NULL){
2699                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2700                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2701                     bd_addr_copy(hci_stack->decline_addr, addr);
2702                     break;
2703                 }
2704             }
2705 
2706             // TODO: eval COD 8-10
2707             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2708             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2709             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2710             if (!conn) {
2711                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2712             }
2713             if (!conn) {
2714                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2715                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2716                 bd_addr_copy(hci_stack->decline_addr, addr);
2717                 break;
2718             }
2719             conn->role  = HCI_ROLE_SLAVE;
2720             conn->state = RECEIVED_CONNECTION_REQUEST;
2721             // store info about eSCO
2722             if (link_type == HCI_LINK_TYPE_ESCO){
2723                 conn->remote_supported_features[0] |= 1;
2724             }
2725             hci_run();
2726             break;
2727 
2728         case HCI_EVENT_CONNECTION_COMPLETE:
2729             // Connection management
2730             reverse_bd_addr(&packet[5], addr);
2731             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2732             addr_type = BD_ADDR_TYPE_ACL;
2733             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2734             if (conn) {
2735                 if (!packet[2]){
2736                     conn->state = OPEN;
2737                     conn->con_handle = little_endian_read_16(packet, 3);
2738 
2739                     // queue set supervision timeout if we're master
2740                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2741                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2742                     }
2743 
2744                     // restart timer
2745                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2746                     btstack_run_loop_add_timer(&conn->timeout);
2747 
2748                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2749 
2750                     hci_emit_nr_connections_changed();
2751                 } else {
2752                     // connection failed
2753                     hci_handle_connection_failed(conn, packet[2]);
2754                 }
2755             }
2756             break;
2757 
2758         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2759             reverse_bd_addr(&packet[5], addr);
2760             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2761             if (packet[2]){
2762                 // connection failed
2763                 break;
2764             }
2765             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2766             if (!conn) {
2767                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2768             }
2769             if (!conn) {
2770                 break;
2771             }
2772             conn->state = OPEN;
2773             conn->con_handle = little_endian_read_16(packet, 3);
2774 
2775 #ifdef ENABLE_SCO_OVER_HCI
2776             // update SCO
2777             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2778                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2779             }
2780             // trigger can send now
2781             if (hci_have_usb_transport()){
2782                 hci_stack->sco_can_send_now = true;
2783             }
2784 #endif
2785 #ifdef HAVE_SCO_TRANSPORT
2786             // configure sco transport
2787             if (hci_stack->sco_transport != NULL){
2788                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2789                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2790             }
2791 #endif
2792             break;
2793 
2794         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2795             handle = little_endian_read_16(packet, 3);
2796             conn = hci_connection_for_handle(handle);
2797             if (!conn) break;
2798             if (!packet[2]){
2799                 const uint8_t * features = &packet[5];
2800                 hci_handle_remote_features_page_0(conn, features);
2801 
2802                 // read extended features if possible
2803                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2804                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2805                     break;
2806                 }
2807             }
2808             hci_handle_remote_features_received(conn);
2809             break;
2810 
2811         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2812             handle = little_endian_read_16(packet, 3);
2813             conn = hci_connection_for_handle(handle);
2814             if (!conn) break;
2815             // status = ok, page = 1
2816             if (!packet[2]) {
2817                 uint8_t page_number = packet[5];
2818                 uint8_t maximum_page_number = packet[6];
2819                 const uint8_t * features = &packet[7];
2820                 bool done = false;
2821                 switch (page_number){
2822                     case 1:
2823                         hci_handle_remote_features_page_1(conn, features);
2824                         if (maximum_page_number >= 2){
2825                             // get Secure Connections (Controller) from Page 2 if available
2826                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2827                         } else {
2828                             // otherwise, assume SC (Controller) == SC (Host)
2829                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2830                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2831                             }
2832                             done = true;
2833                         }
2834                         break;
2835                     case 2:
2836                         hci_handle_remote_features_page_2(conn, features);
2837                         done = true;
2838                         break;
2839                     default:
2840                         break;
2841                 }
2842                 if (!done) break;
2843             }
2844             hci_handle_remote_features_received(conn);
2845             break;
2846 
2847         case HCI_EVENT_LINK_KEY_REQUEST:
2848 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2849             hci_event_link_key_request_get_bd_addr(packet, addr);
2850             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2851             if (!conn) break;
2852 
2853             // lookup link key in db if not cached
2854             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2855                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2856             }
2857 
2858             // response sent by hci_run()
2859             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2860 #endif
2861             break;
2862 
2863         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2864             hci_event_link_key_request_get_bd_addr(packet, addr);
2865             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2866             if (!conn) break;
2867 
2868             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2869 
2870             // CVE-2020-26555: ignore NULL link key
2871             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2872             if (btstack_is_null(&packet[8], 16)) break;
2873 
2874             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2875             // Change Connection Encryption keeps link key type
2876             if (link_key_type != CHANGED_COMBINATION_KEY){
2877                 conn->link_key_type = link_key_type;
2878             }
2879 
2880             // cache link key. link keys stored in little-endian format for legacy reasons
2881             memcpy(&conn->link_key, &packet[8], 16);
2882 
2883             // only store link key:
2884             // - if bondable enabled
2885             if (hci_stack->bondable == false) break;
2886             // - if security level sufficient
2887             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2888             // - for SSP, also check if remote side requested bonding as well
2889             if (conn->link_key_type != COMBINATION_KEY){
2890                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2891                 if (!remote_bonding){
2892                     break;
2893                 }
2894             }
2895             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2896             break;
2897         }
2898 
2899         case HCI_EVENT_PIN_CODE_REQUEST:
2900             hci_event_pin_code_request_get_bd_addr(packet, addr);
2901             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2902             if (!conn) break;
2903 
2904             hci_pairing_started(conn, false);
2905             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2906             if (!hci_stack->bondable ){
2907                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2908                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2909                 hci_run();
2910                 return;
2911             }
2912             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2913             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2914                 log_info("Level 4 required, but SC not supported -> abort");
2915                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2916                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2917                 hci_run();
2918                 return;
2919             }
2920             break;
2921 
2922         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2923             hci_event_io_capability_response_get_bd_addr(packet, addr);
2924             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2925             if (!conn) break;
2926 
2927             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2928             hci_pairing_started(conn, true);
2929             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2930             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2931 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2932             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2933 #endif
2934             break;
2935 
2936         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2937             hci_event_io_capability_response_get_bd_addr(packet, addr);
2938             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2939             if (!conn) break;
2940 
2941             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2942             hci_connection_timestamp(conn);
2943             hci_pairing_started(conn, true);
2944             break;
2945 
2946 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2947         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2948             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2949             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2950             if (!conn) break;
2951 
2952             hci_connection_timestamp(conn);
2953 
2954             hci_pairing_started(conn, true);
2955 
2956             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2957             break;
2958 #endif
2959 
2960         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2961             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2962             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2963             if (!conn) break;
2964             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2965                 if (hci_stack->ssp_auto_accept){
2966                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2967                 };
2968             } else {
2969                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2970                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2971                 // don't forward event to app
2972                 hci_run();
2973                 return;
2974             }
2975             break;
2976 
2977         case HCI_EVENT_USER_PASSKEY_REQUEST:
2978             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2979             if (hci_stack->ssp_auto_accept){
2980                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2981             };
2982             break;
2983 
2984         case HCI_EVENT_MODE_CHANGE:
2985             handle = hci_event_mode_change_get_handle(packet);
2986             conn = hci_connection_for_handle(handle);
2987             if (!conn) break;
2988             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2989             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2990             break;
2991 #endif
2992 
2993         case HCI_EVENT_ENCRYPTION_CHANGE:
2994             handle = hci_event_encryption_change_get_connection_handle(packet);
2995             conn = hci_connection_for_handle(handle);
2996             if (!conn) break;
2997             if (hci_event_encryption_change_get_status(packet) == 0u) {
2998                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2999                 if (encryption_enabled){
3000                     if (hci_is_le_connection(conn)){
3001                         // For LE, we accept connection as encrypted
3002                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3003                     }
3004 #ifdef ENABLE_CLASSIC
3005                     else {
3006 
3007                         // dedicated bonding: send result and disconnect
3008                         if (conn->bonding_flags & BONDING_DEDICATED){
3009                             conn->bonding_flags &= ~BONDING_DEDICATED;
3010                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3011                             conn->bonding_status = packet[2];
3012                             break;
3013                         }
3014 
3015                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3016                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3017                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3018                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3019                             log_info("SC during pairing, but only E0 now -> abort");
3020                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3021                             break;
3022                         }
3023 
3024                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3025                         if (connected_uses_aes_ccm){
3026                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3027                         }
3028 
3029 #ifdef ENABLE_TESTING_SUPPORT
3030                         // work around for issue with PTS dongle
3031                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3032 #endif
3033 
3034                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3035                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3036                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3037                         } else {
3038                             // if not, pretend everything is perfect
3039                             hci_handle_read_encryption_key_size_complete(conn, 16);
3040                         }
3041                     }
3042 #endif
3043                 } else {
3044                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3045                 }
3046             }
3047 
3048             break;
3049 
3050 #ifdef ENABLE_CLASSIC
3051         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3052             handle = hci_event_authentication_complete_get_connection_handle(packet);
3053             conn = hci_connection_for_handle(handle);
3054             if (!conn) break;
3055 
3056             // clear authentication active flag
3057             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3058             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3059 
3060             // authenticated only if auth status == 0
3061             if (hci_event_authentication_complete_get_status(packet) == 0){
3062                 // authenticated
3063                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3064 
3065                 // If not already encrypted, start encryption
3066                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3067                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3068                     break;
3069                 }
3070             }
3071 
3072             // emit updated security level
3073             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3074             break;
3075 
3076         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3077             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3078             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3079             if (!conn) break;
3080 
3081             // treat successfully paired connection as authenticated
3082             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3083                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3084             }
3085 
3086             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3087             break;
3088 #endif
3089 
3090         // HCI_EVENT_DISCONNECTION_COMPLETE
3091         // has been split, to first notify stack before shutting connection down
3092         // see end of function, too.
3093         case HCI_EVENT_DISCONNECTION_COMPLETE:
3094             if (packet[2]) break;   // status != 0
3095             handle = little_endian_read_16(packet, 3);
3096             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3097             if (hci_stack->acl_fragmentation_total_size > 0u) {
3098                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3099                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3100                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3101                     hci_stack->acl_fragmentation_total_size = 0;
3102                     hci_stack->acl_fragmentation_pos = 0;
3103                     if (release_buffer){
3104                         hci_release_packet_buffer();
3105                     }
3106                 }
3107             }
3108 
3109             conn = hci_connection_for_handle(handle);
3110             if (!conn) break;
3111 #ifdef ENABLE_CLASSIC
3112             // pairing failed if it was ongoing
3113             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3114 #endif
3115 
3116             // emit dedicatd bonding event
3117             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3118                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3119             }
3120 
3121             // mark connection for shutdown, stop timers, reset state
3122             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3123             hci_connection_stop_timer(conn);
3124             hci_connection_init(conn);
3125 
3126 #ifdef ENABLE_BLE
3127 #ifdef ENABLE_LE_PERIPHERAL
3128             // re-enable advertisements for le connections if active
3129             if (hci_is_le_connection(conn)){
3130                 hci_update_advertisements_enabled_for_current_roles();
3131             }
3132 #endif
3133 #endif
3134             break;
3135 
3136         case HCI_EVENT_HARDWARE_ERROR:
3137             log_error("Hardware Error: 0x%02x", packet[2]);
3138             if (hci_stack->hardware_error_callback){
3139                 (*hci_stack->hardware_error_callback)(packet[2]);
3140             } else {
3141                 // if no special requests, just reboot stack
3142                 hci_power_control_off();
3143                 hci_power_control_on();
3144             }
3145             break;
3146 
3147 #ifdef ENABLE_CLASSIC
3148         case HCI_EVENT_ROLE_CHANGE:
3149             if (packet[2]) break;   // status != 0
3150             reverse_bd_addr(&packet[3], addr);
3151             addr_type = BD_ADDR_TYPE_ACL;
3152             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3153             if (!conn) break;
3154             conn->role = packet[9];
3155             break;
3156 #endif
3157 
3158         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3159             // release packet buffer only for asynchronous transport and if there are not further fragements
3160             if (hci_transport_synchronous()) {
3161                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3162                 return; // instead of break: to avoid re-entering hci_run()
3163             }
3164             hci_stack->acl_fragmentation_tx_active = 0;
3165             if (hci_stack->acl_fragmentation_total_size) break;
3166             hci_release_packet_buffer();
3167 
3168             // L2CAP receives this event via the hci_emit_event below
3169 
3170 #ifdef ENABLE_CLASSIC
3171             // For SCO, we do the can_send_now_check here
3172             hci_notify_if_sco_can_send_now();
3173 #endif
3174             break;
3175 
3176 #ifdef ENABLE_CLASSIC
3177         case HCI_EVENT_SCO_CAN_SEND_NOW:
3178             // For SCO, we do the can_send_now_check here
3179             hci_stack->sco_can_send_now = true;
3180             hci_notify_if_sco_can_send_now();
3181             return;
3182 
3183         // explode inquriy results for easier consumption
3184         case HCI_EVENT_INQUIRY_RESULT:
3185         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3186         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3187             gap_inquiry_explode(packet, size);
3188             break;
3189 #endif
3190 
3191 #ifdef ENABLE_BLE
3192         case HCI_EVENT_LE_META:
3193             switch (packet[2]){
3194 #ifdef ENABLE_LE_CENTRAL
3195                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3196                     // log_info("advertising report received");
3197                     if (!hci_stack->le_scanning_enabled) break;
3198                     le_handle_advertisement_report(packet, size);
3199                     break;
3200 #endif
3201                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3202 					event_handle_le_connection_complete(packet);
3203                     break;
3204 
3205                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3206                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3207                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3208                     conn = hci_connection_for_handle(handle);
3209                     if (!conn) break;
3210                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3211                     break;
3212 
3213                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3214                     // connection
3215                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3216                     conn = hci_connection_for_handle(handle);
3217                     if (conn) {
3218                         // read arguments
3219                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3220                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3221                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3222                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3223 
3224                         // validate against current connection parameter range
3225                         le_connection_parameter_range_t existing_range;
3226                         gap_get_connection_parameter_range(&existing_range);
3227                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3228                         if (update_parameter){
3229                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3230                             conn->le_conn_interval_min = le_conn_interval_min;
3231                             conn->le_conn_interval_max = le_conn_interval_max;
3232                             conn->le_conn_latency = le_conn_latency;
3233                             conn->le_supervision_timeout = le_supervision_timeout;
3234                         } else {
3235                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3236                         }
3237                     }
3238                     break;
3239 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3240                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3241                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3242                     conn = hci_connection_for_handle(handle);
3243                     if (conn) {
3244                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3245                     }
3246                     break;
3247 #endif
3248                 default:
3249                     break;
3250             }
3251             break;
3252 #endif
3253         case HCI_EVENT_VENDOR_SPECIFIC:
3254             // Vendor specific commands often create vendor specific event instead of num completed packets
3255             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3256             switch (hci_stack->manufacturer){
3257                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3258                     hci_stack->num_cmd_packets = 1;
3259                     break;
3260                 default:
3261                     break;
3262             }
3263             break;
3264         default:
3265             break;
3266     }
3267 
3268     handle_event_for_current_stack_state(packet, size);
3269 
3270     // notify upper stack
3271 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3272 
3273     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3274     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3275 		handle = little_endian_read_16(packet, 3);
3276 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3277 		// discard connection if app did not trigger a reconnect in the event handler
3278 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3279 			hci_shutdown_connection(aConn);
3280 		}
3281     }
3282 
3283 	// execute main loop
3284 	hci_run();
3285 }
3286 
3287 #ifdef ENABLE_CLASSIC
3288 
3289 #ifdef ENABLE_SCO_OVER_HCI
3290 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3291 static void sco_schedule_tx(hci_connection_t * conn);
3292 
3293 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3294     log_debug("SCO TX Timeout");
3295     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3296     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3297     if (!conn) return;
3298 
3299     // trigger send
3300     conn->sco_tx_ready = 1;
3301     // extra packet if CVSD but SCO buffer is too short
3302     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3303         conn->sco_tx_ready++;
3304     }
3305     hci_notify_if_sco_can_send_now();
3306 }
3307 
3308 
3309 #define SCO_TX_AFTER_RX_MS (6)
3310 
3311 static void sco_schedule_tx(hci_connection_t * conn){
3312 
3313     uint32_t now = btstack_run_loop_get_time_ms();
3314     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3315     int time_delta_ms = sco_tx_ms - now;
3316 
3317     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3318 
3319     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3320     btstack_run_loop_remove_timer(timer);
3321     btstack_run_loop_set_timer(timer, time_delta_ms);
3322     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3323     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3324     btstack_run_loop_add_timer(timer);
3325 }
3326 #endif
3327 
3328 static void sco_handler(uint8_t * packet, uint16_t size){
3329     // lookup connection struct
3330     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3331     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3332     if (!conn) return;
3333 
3334 #ifdef ENABLE_SCO_OVER_HCI
3335     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3336     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3337         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3338             packet[2] = 0x3c;
3339             memmove(&packet[3], &packet[23], 63);
3340             size = 63;
3341         }
3342     }
3343 
3344     if (hci_have_usb_transport()){
3345         // Nothing to do
3346     } else {
3347         // 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);
3348         if (hci_stack->synchronous_flow_control_enabled == 0){
3349             uint32_t now = btstack_run_loop_get_time_ms();
3350 
3351             if (!conn->sco_rx_valid){
3352                 // ignore first 10 packets
3353                 conn->sco_rx_count++;
3354                 // log_debug("sco rx count %u", conn->sco_rx_count);
3355                 if (conn->sco_rx_count == 10) {
3356                     // use first timestamp as is and pretent it just started
3357                     conn->sco_rx_ms = now;
3358                     conn->sco_rx_valid = 1;
3359                     conn->sco_rx_count = 0;
3360                     sco_schedule_tx(conn);
3361                 }
3362             } else {
3363                 // track expected arrival timme
3364                 conn->sco_rx_count++;
3365                 conn->sco_rx_ms += 7;
3366                 int delta = (int32_t) (now - conn->sco_rx_ms);
3367                 if (delta > 0){
3368                     conn->sco_rx_ms++;
3369                 }
3370                 // log_debug("sco rx %u", conn->sco_rx_ms);
3371                 sco_schedule_tx(conn);
3372             }
3373         }
3374     }
3375 #endif
3376 
3377     // deliver to app
3378     if (hci_stack->sco_packet_handler) {
3379         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3380     }
3381 
3382 #ifdef HAVE_SCO_TRANSPORT
3383     // We can send one packet for each received packet
3384     conn->sco_tx_ready++;
3385     hci_notify_if_sco_can_send_now();
3386 #endif
3387 
3388 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3389     conn->num_packets_completed++;
3390     hci_stack->host_completed_packets = 1;
3391     hci_run();
3392 #endif
3393 }
3394 #endif
3395 
3396 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3397     hci_dump_packet(packet_type, 1, packet, size);
3398     switch (packet_type) {
3399         case HCI_EVENT_PACKET:
3400             event_handler(packet, size);
3401             break;
3402         case HCI_ACL_DATA_PACKET:
3403             acl_handler(packet, size);
3404             break;
3405 #ifdef ENABLE_CLASSIC
3406         case HCI_SCO_DATA_PACKET:
3407             sco_handler(packet, size);
3408             break;
3409 #endif
3410         default:
3411             break;
3412     }
3413 }
3414 
3415 /**
3416  * @brief Add event packet handler.
3417  */
3418 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3419     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3420 }
3421 
3422 /**
3423  * @brief Remove event packet handler.
3424  */
3425 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3426     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3427 }
3428 
3429 /** Register HCI packet handlers */
3430 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3431     hci_stack->acl_packet_handler = handler;
3432 }
3433 
3434 #ifdef ENABLE_CLASSIC
3435 /**
3436  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3437  */
3438 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3439     hci_stack->sco_packet_handler = handler;
3440 }
3441 #endif
3442 
3443 static void hci_state_reset(void){
3444     // no connections yet
3445     hci_stack->connections = NULL;
3446 
3447     // keep discoverable/connectable as this has been requested by the client(s)
3448     // hci_stack->discoverable = 0;
3449     // hci_stack->connectable = 0;
3450     // hci_stack->bondable = 1;
3451     // hci_stack->own_addr_type = 0;
3452 
3453     // buffer is free
3454     hci_stack->hci_packet_buffer_reserved = false;
3455 
3456     // no pending cmds
3457     hci_stack->decline_reason = 0;
3458 
3459     hci_stack->secure_connections_active = false;
3460 
3461 #ifdef ENABLE_CLASSIC
3462     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3463     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3464 
3465     hci_stack->gap_tasks =
3466             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3467             GAP_TASK_SET_CLASS_OF_DEVICE |
3468             GAP_TASK_SET_LOCAL_NAME |
3469             GAP_TASK_SET_EIR_DATA |
3470             GAP_TASK_WRITE_SCAN_ENABLE |
3471             GAP_TASK_WRITE_PAGE_TIMEOUT;
3472 #endif
3473 
3474 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3475     hci_stack->classic_read_local_oob_data = false;
3476     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3477 #endif
3478 
3479     // LE
3480 #ifdef ENABLE_BLE
3481     memset(hci_stack->le_random_address, 0, 6);
3482     hci_stack->le_random_address_set = 0;
3483 #endif
3484 #ifdef ENABLE_LE_CENTRAL
3485     hci_stack->le_scanning_active  = false;
3486     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3487     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3488     hci_stack->le_whitelist_capacity = 0;
3489 #endif
3490 #ifdef ENABLE_LE_PERIPHERAL
3491     hci_stack->le_advertisements_active = false;
3492     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3493         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3494     }
3495     if (hci_stack->le_advertisements_data != NULL){
3496         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3497     }
3498 #endif
3499 }
3500 
3501 #ifdef ENABLE_CLASSIC
3502 /**
3503  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3504  */
3505 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3506     // store and open remote device db
3507     hci_stack->link_key_db = link_key_db;
3508     if (hci_stack->link_key_db) {
3509         hci_stack->link_key_db->open();
3510     }
3511 }
3512 #endif
3513 
3514 void hci_init(const hci_transport_t *transport, const void *config){
3515 
3516 #ifdef HAVE_MALLOC
3517     if (!hci_stack) {
3518         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3519     }
3520 #else
3521     hci_stack = &hci_stack_static;
3522 #endif
3523     memset(hci_stack, 0, sizeof(hci_stack_t));
3524 
3525     // reference to use transport layer implementation
3526     hci_stack->hci_transport = transport;
3527 
3528     // reference to used config
3529     hci_stack->config = config;
3530 
3531     // setup pointer for outgoing packet buffer
3532     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3533 
3534     // max acl payload size defined in config.h
3535     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3536 
3537     // register packet handlers with transport
3538     transport->register_packet_handler(&packet_handler);
3539 
3540     hci_stack->state = HCI_STATE_OFF;
3541 
3542     // class of device
3543     hci_stack->class_of_device = 0x007a020c; // Smartphone
3544 
3545     // bondable by default
3546     hci_stack->bondable = 1;
3547 
3548 #ifdef ENABLE_CLASSIC
3549     // classic name
3550     hci_stack->local_name = default_classic_name;
3551 
3552     // Master slave policy
3553     hci_stack->master_slave_policy = 1;
3554 
3555     // Allow Role Switch
3556     hci_stack->allow_role_switch = 1;
3557 
3558     // Default / minimum security level = 2
3559     hci_stack->gap_security_level = LEVEL_2;
3560 
3561     // Default Security Mode 4
3562     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3563 
3564     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3565     hci_stack->gap_required_encyrption_key_size = 7;
3566 
3567     // Link Supervision Timeout
3568     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3569 
3570 #endif
3571 
3572     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3573     hci_stack->ssp_enable = 1;
3574     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3575     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3576     hci_stack->ssp_auto_accept = 1;
3577 
3578     // Secure Connections: enable (requires support from Controller)
3579     hci_stack->secure_connections_enable = true;
3580 
3581     // voice setting - signed 16 bit pcm data with CVSD over the air
3582     hci_stack->sco_voice_setting = 0x60;
3583 
3584 #ifdef ENABLE_LE_CENTRAL
3585     // connection parameter to use for outgoing connections
3586     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3587     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3588     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3589     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3590     hci_stack->le_connection_latency      = 4;         // 4
3591     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3592     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3593     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3594 
3595     // default LE Scanning
3596     hci_stack->le_scan_type     =   0x1; // active
3597     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3598     hci_stack->le_scan_window   =  0x30; //  30 ms
3599 #endif
3600 
3601 #ifdef ENABLE_LE_PERIPHERAL
3602     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3603 #endif
3604 
3605     // connection parameter range used to answer connection parameter update requests in l2cap
3606     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3607     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3608     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3609     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3610     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3611     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3612 
3613     hci_state_reset();
3614 }
3615 
3616 void hci_deinit(void){
3617 #ifdef HAVE_MALLOC
3618     if (hci_stack) {
3619         free(hci_stack);
3620     }
3621 #endif
3622     hci_stack = NULL;
3623 
3624 #ifdef ENABLE_CLASSIC
3625     disable_l2cap_timeouts = 0;
3626 #endif
3627 }
3628 
3629 /**
3630  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3631  */
3632 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3633     hci_stack->chipset = chipset_driver;
3634 
3635     // reset chipset driver - init is also called on power_up
3636     if (hci_stack->chipset && hci_stack->chipset->init){
3637         hci_stack->chipset->init(hci_stack->config);
3638     }
3639 }
3640 
3641 /**
3642  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3643  */
3644 void hci_set_control(const btstack_control_t *hardware_control){
3645     // references to used control implementation
3646     hci_stack->control = hardware_control;
3647     // init with transport config
3648     hardware_control->init(hci_stack->config);
3649 }
3650 
3651 static void hci_discard_connections(void){
3652     btstack_linked_list_iterator_t lit;
3653     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3654     while (btstack_linked_list_iterator_has_next(&lit)){
3655         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3656         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3657         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3658         hci_shutdown_connection(connection);
3659     }
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     hci_discard_connections();
3672 
3673     hci_power_control(HCI_POWER_OFF);
3674 
3675 #ifdef HAVE_MALLOC
3676     free(hci_stack);
3677 #endif
3678     hci_stack = NULL;
3679 }
3680 
3681 #ifdef HAVE_SCO_TRANSPORT
3682 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3683     hci_stack->sco_transport = sco_transport;
3684     sco_transport->register_packet_handler(&packet_handler);
3685 }
3686 #endif
3687 
3688 #ifdef ENABLE_CLASSIC
3689 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3690     // validate ranage and set
3691     if (encryption_key_size < 7)  return;
3692     if (encryption_key_size > 16) return;
3693     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3694 }
3695 
3696 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3697     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3698         hci_stack->gap_security_mode = security_mode;
3699         return ERROR_CODE_SUCCESS;
3700     } else {
3701         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3702     }
3703 }
3704 
3705 gap_security_mode_t gap_get_security_mode(void){
3706     return hci_stack->gap_security_mode;
3707 }
3708 
3709 void gap_set_security_level(gap_security_level_t security_level){
3710     hci_stack->gap_security_level = security_level;
3711 }
3712 
3713 gap_security_level_t gap_get_security_level(void){
3714     if (hci_stack->gap_secure_connections_only_mode){
3715         return LEVEL_4;
3716     }
3717     return hci_stack->gap_security_level;
3718 }
3719 
3720 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3721     hci_stack->gap_minimal_service_security_level = security_level;
3722 }
3723 
3724 void gap_set_secure_connections_only_mode(bool enable){
3725     hci_stack->gap_secure_connections_only_mode = enable;
3726 }
3727 
3728 bool gap_get_secure_connections_only_mode(void){
3729     return hci_stack->gap_secure_connections_only_mode;
3730 }
3731 #endif
3732 
3733 #ifdef ENABLE_CLASSIC
3734 void gap_set_class_of_device(uint32_t class_of_device){
3735     hci_stack->class_of_device = class_of_device;
3736     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3737     hci_run();
3738 }
3739 
3740 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3741     hci_stack->default_link_policy_settings = default_link_policy_settings;
3742     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3743     hci_run();
3744 }
3745 
3746 void gap_set_allow_role_switch(bool allow_role_switch){
3747     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3748 }
3749 
3750 uint8_t hci_get_allow_role_switch(void){
3751     return  hci_stack->allow_role_switch;
3752 }
3753 
3754 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3755     hci_stack->link_supervision_timeout = link_supervision_timeout;
3756 }
3757 
3758 void hci_disable_l2cap_timeout_check(void){
3759     disable_l2cap_timeouts = 1;
3760 }
3761 #endif
3762 
3763 #ifndef HAVE_HOST_CONTROLLER_API
3764 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3765 void hci_set_bd_addr(bd_addr_t addr){
3766     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3767     hci_stack->custom_bd_addr_set = 1;
3768 }
3769 #endif
3770 
3771 // State-Module-Driver overview
3772 // state                    module  low-level
3773 // HCI_STATE_OFF             off      close
3774 // HCI_STATE_INITIALIZING,   on       open
3775 // HCI_STATE_WORKING,        on       open
3776 // HCI_STATE_HALTING,        on       open
3777 // HCI_STATE_SLEEPING,    off/sleep   close
3778 // HCI_STATE_FALLING_ASLEEP  on       open
3779 
3780 static int hci_power_control_on(void){
3781 
3782     // power on
3783     int err = 0;
3784     if (hci_stack->control && hci_stack->control->on){
3785         err = (*hci_stack->control->on)();
3786     }
3787     if (err){
3788         log_error( "POWER_ON failed");
3789         hci_emit_hci_open_failed();
3790         return err;
3791     }
3792 
3793     // int chipset driver
3794     if (hci_stack->chipset && hci_stack->chipset->init){
3795         hci_stack->chipset->init(hci_stack->config);
3796     }
3797 
3798     // init transport
3799     if (hci_stack->hci_transport->init){
3800         hci_stack->hci_transport->init(hci_stack->config);
3801     }
3802 
3803     // open transport
3804     err = hci_stack->hci_transport->open();
3805     if (err){
3806         log_error( "HCI_INIT failed, turning Bluetooth off again");
3807         if (hci_stack->control && hci_stack->control->off){
3808             (*hci_stack->control->off)();
3809         }
3810         hci_emit_hci_open_failed();
3811         return err;
3812     }
3813     return 0;
3814 }
3815 
3816 static void hci_power_control_off(void){
3817 
3818     log_info("hci_power_control_off");
3819 
3820     // close low-level device
3821     hci_stack->hci_transport->close();
3822 
3823     log_info("hci_power_control_off - hci_transport closed");
3824 
3825     // power off
3826     if (hci_stack->control && hci_stack->control->off){
3827         (*hci_stack->control->off)();
3828     }
3829 
3830     log_info("hci_power_control_off - control closed");
3831 
3832     hci_stack->state = HCI_STATE_OFF;
3833 }
3834 
3835 static void hci_power_control_sleep(void){
3836 
3837     log_info("hci_power_control_sleep");
3838 
3839 #if 0
3840     // don't close serial port during sleep
3841 
3842     // close low-level device
3843     hci_stack->hci_transport->close(hci_stack->config);
3844 #endif
3845 
3846     // sleep mode
3847     if (hci_stack->control && hci_stack->control->sleep){
3848         (*hci_stack->control->sleep)();
3849     }
3850 
3851     hci_stack->state = HCI_STATE_SLEEPING;
3852 }
3853 
3854 static int hci_power_control_wake(void){
3855 
3856     log_info("hci_power_control_wake");
3857 
3858     // wake on
3859     if (hci_stack->control && hci_stack->control->wake){
3860         (*hci_stack->control->wake)();
3861     }
3862 
3863 #if 0
3864     // open low-level device
3865     int err = hci_stack->hci_transport->open(hci_stack->config);
3866     if (err){
3867         log_error( "HCI_INIT failed, turning Bluetooth off again");
3868         if (hci_stack->control && hci_stack->control->off){
3869             (*hci_stack->control->off)();
3870         }
3871         hci_emit_hci_open_failed();
3872         return err;
3873     }
3874 #endif
3875 
3876     return 0;
3877 }
3878 
3879 static void hci_power_transition_to_initializing(void){
3880     // set up state machine
3881     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3882     hci_stack->hci_packet_buffer_reserved = false;
3883     hci_stack->state = HCI_STATE_INITIALIZING;
3884     hci_stack->substate = HCI_INIT_SEND_RESET;
3885 }
3886 
3887 // returns error
3888 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3889     int err;
3890     switch (power_mode){
3891         case HCI_POWER_ON:
3892             err = hci_power_control_on();
3893             if (err != 0) {
3894                 log_error("hci_power_control_on() error %d", err);
3895                 return err;
3896             }
3897             hci_power_transition_to_initializing();
3898             break;
3899         case HCI_POWER_OFF:
3900             // do nothing
3901             break;
3902         case HCI_POWER_SLEEP:
3903             // do nothing (with SLEEP == OFF)
3904             break;
3905         default:
3906             btstack_assert(false);
3907             break;
3908     }
3909     return ERROR_CODE_SUCCESS;
3910 }
3911 
3912 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3913     switch (power_mode){
3914         case HCI_POWER_ON:
3915             // do nothing
3916             break;
3917         case HCI_POWER_OFF:
3918             // no connections yet, just turn it off
3919             hci_power_control_off();
3920             break;
3921         case HCI_POWER_SLEEP:
3922             // no connections yet, just turn it off
3923             hci_power_control_sleep();
3924             break;
3925         default:
3926             btstack_assert(false);
3927             break;
3928     }
3929     return ERROR_CODE_SUCCESS;
3930 }
3931 
3932 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3933     switch (power_mode){
3934         case HCI_POWER_ON:
3935             // do nothing
3936             break;
3937         case HCI_POWER_OFF:
3938             // see hci_run
3939             hci_stack->state = HCI_STATE_HALTING;
3940             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3941             // setup watchdog timer for disconnect - only triggers if Controller does not respond anymore
3942             btstack_run_loop_set_timer(&hci_stack->timeout, 1000);
3943             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3944             btstack_run_loop_add_timer(&hci_stack->timeout);
3945             break;
3946         case HCI_POWER_SLEEP:
3947             // see hci_run
3948             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3949             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3950             break;
3951         default:
3952             btstack_assert(false);
3953             break;
3954     }
3955     return ERROR_CODE_SUCCESS;
3956 }
3957 
3958 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3959     switch (power_mode){
3960         case HCI_POWER_ON:
3961             hci_power_transition_to_initializing();
3962             break;
3963         case HCI_POWER_OFF:
3964             // do nothing
3965             break;
3966         case HCI_POWER_SLEEP:
3967             // see hci_run
3968             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3969             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3970             break;
3971         default:
3972             btstack_assert(false);
3973             break;
3974     }
3975     return ERROR_CODE_SUCCESS;
3976 }
3977 
3978 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3979     switch (power_mode){
3980         case HCI_POWER_ON:
3981             hci_power_transition_to_initializing();
3982             break;
3983         case HCI_POWER_OFF:
3984             // see hci_run
3985             hci_stack->state = HCI_STATE_HALTING;
3986             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3987             break;
3988         case HCI_POWER_SLEEP:
3989             // do nothing
3990             break;
3991         default:
3992             btstack_assert(false);
3993             break;
3994     }
3995     return ERROR_CODE_SUCCESS;
3996 }
3997 
3998 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3999     int err;
4000     switch (power_mode){
4001         case HCI_POWER_ON:
4002             err = hci_power_control_wake();
4003             if (err) return err;
4004             hci_power_transition_to_initializing();
4005             break;
4006         case HCI_POWER_OFF:
4007             hci_stack->state = HCI_STATE_HALTING;
4008             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4009             break;
4010         case HCI_POWER_SLEEP:
4011             // do nothing
4012             break;
4013         default:
4014             btstack_assert(false);
4015             break;
4016     }
4017     return ERROR_CODE_SUCCESS;
4018 }
4019 
4020 int hci_power_control(HCI_POWER_MODE power_mode){
4021     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4022     int err = 0;
4023     switch (hci_stack->state){
4024         case HCI_STATE_OFF:
4025             err = hci_power_control_state_off(power_mode);
4026             break;
4027         case HCI_STATE_INITIALIZING:
4028             err = hci_power_control_state_initializing(power_mode);
4029             break;
4030         case HCI_STATE_WORKING:
4031             err = hci_power_control_state_working(power_mode);
4032             break;
4033         case HCI_STATE_HALTING:
4034             err = hci_power_control_state_halting(power_mode);
4035             break;
4036         case HCI_STATE_FALLING_ASLEEP:
4037             err = hci_power_control_state_falling_asleep(power_mode);
4038             break;
4039         case HCI_STATE_SLEEPING:
4040             err = hci_power_control_state_sleeping(power_mode);
4041             break;
4042         default:
4043             btstack_assert(false);
4044             break;
4045     }
4046     if (err != 0){
4047         return err;
4048     }
4049 
4050     // create internal event
4051 	hci_emit_state();
4052 
4053 	// trigger next/first action
4054 	hci_run();
4055 
4056     return 0;
4057 }
4058 
4059 
4060 static void hci_halting_run(void){
4061 
4062     log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4063 
4064     hci_connection_t * connection;
4065 
4066     switch (hci_stack->substate) {
4067         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4068             case HCI_HALTING_DISCONNECT_ALL_TIMER:
4069 
4070 #ifdef ENABLE_BLE
4071 #ifdef ENABLE_LE_CENTRAL
4072     hci_whitelist_free();
4073 #endif
4074 #endif
4075     // close all open connections
4076     connection = (hci_connection_t *) hci_stack->connections;
4077     if (connection) {
4078         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4079         if (!hci_can_send_command_packet_now()) return;
4080 
4081         // check state
4082         if (connection->state == SENT_DISCONNECT) return;
4083         connection->state = SENT_DISCONNECT;
4084 
4085         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4086 
4087         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4088         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4089 
4090         // ... which would be ignored anyway as we shutdown (free) the connection now
4091         hci_shutdown_connection(connection);
4092 
4093         // finally, send the disconnect command
4094         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4095         return;
4096     }
4097 
4098     btstack_run_loop_remove_timer(&hci_stack->timeout);
4099 
4100     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER) {
4101         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4102         log_info("HCI_STATE_HALTING: wait 50 ms");
4103         hci_stack->substate = HCI_HALTING_W4_TIMER;
4104         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4105         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4106         btstack_run_loop_add_timer(&hci_stack->timeout);
4107         break;
4108     }
4109 
4110     /* fall through */
4111 
4112     case HCI_HALTING_CLOSE:
4113         // close left over connections (that had not been properly closed before)
4114         hci_discard_connections();
4115 
4116         log_info("HCI_STATE_HALTING, calling off");
4117 
4118         // switch mode
4119         hci_power_control_off();
4120 
4121         log_info("HCI_STATE_HALTING, emitting state");
4122         hci_emit_state();
4123         log_info("HCI_STATE_HALTING, done");
4124         break;
4125 
4126         case HCI_HALTING_W4_TIMER:
4127             // keep waiting
4128 
4129             break;
4130         default:
4131             break;
4132     }
4133 };
4134 
4135 static void hci_falling_asleep_run(void){
4136     hci_connection_t * connection;
4137     switch(hci_stack->substate) {
4138         case HCI_FALLING_ASLEEP_DISCONNECT:
4139             log_info("HCI_STATE_FALLING_ASLEEP");
4140             // close all open connections
4141             connection =  (hci_connection_t *) hci_stack->connections;
4142             if (connection){
4143 
4144                 // send disconnect
4145                 if (!hci_can_send_command_packet_now()) return;
4146 
4147                 log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4148                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4149 
4150                 // send disconnected event right away - causes higher layer connections to get closed, too.
4151                 hci_shutdown_connection(connection);
4152                 return;
4153             }
4154 
4155             if (hci_classic_supported()){
4156                 // disable page and inquiry scan
4157                 if (!hci_can_send_command_packet_now()) return;
4158 
4159                 log_info("HCI_STATE_HALTING, disabling inq scans");
4160                 hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4161 
4162                 // continue in next sub state
4163                 hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4164                 break;
4165             }
4166 
4167             /* fall through */
4168 
4169             case HCI_FALLING_ASLEEP_COMPLETE:
4170                 log_info("HCI_STATE_HALTING, calling sleep");
4171                 // switch mode
4172                 hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4173                 hci_emit_state();
4174                 break;
4175 
4176                 default:
4177                     break;
4178     }
4179 }
4180 
4181 #ifdef ENABLE_CLASSIC
4182 
4183 static void hci_update_scan_enable(void){
4184     // 2 = page scan, 1 = inq scan
4185     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4186     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4187     hci_run();
4188 }
4189 
4190 void gap_discoverable_control(uint8_t enable){
4191     if (enable) enable = 1; // normalize argument
4192 
4193     if (hci_stack->discoverable == enable){
4194         hci_emit_discoverable_enabled(hci_stack->discoverable);
4195         return;
4196     }
4197 
4198     hci_stack->discoverable = enable;
4199     hci_update_scan_enable();
4200 }
4201 
4202 void gap_connectable_control(uint8_t enable){
4203     if (enable) enable = 1; // normalize argument
4204 
4205     // don't emit event
4206     if (hci_stack->connectable == enable) return;
4207 
4208     hci_stack->connectable = enable;
4209     hci_update_scan_enable();
4210 }
4211 #endif
4212 
4213 void gap_local_bd_addr(bd_addr_t address_buffer){
4214     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4215 }
4216 
4217 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4218 static void hci_host_num_completed_packets(void){
4219 
4220     // create packet manually as arrays are not supported and num_commands should not get reduced
4221     hci_reserve_packet_buffer();
4222     uint8_t * packet = hci_get_outgoing_packet_buffer();
4223 
4224     uint16_t size = 0;
4225     uint16_t num_handles = 0;
4226     packet[size++] = 0x35;
4227     packet[size++] = 0x0c;
4228     size++;  // skip param len
4229     size++;  // skip num handles
4230 
4231     // add { handle, packets } entries
4232     btstack_linked_item_t * it;
4233     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4234         hci_connection_t * connection = (hci_connection_t *) it;
4235         if (connection->num_packets_completed){
4236             little_endian_store_16(packet, size, connection->con_handle);
4237             size += 2;
4238             little_endian_store_16(packet, size, connection->num_packets_completed);
4239             size += 2;
4240             //
4241             num_handles++;
4242             connection->num_packets_completed = 0;
4243         }
4244     }
4245 
4246     packet[2] = size - 3;
4247     packet[3] = num_handles;
4248 
4249     hci_stack->host_completed_packets = 0;
4250 
4251     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4252     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4253 
4254     // release packet buffer for synchronous transport implementations
4255     if (hci_transport_synchronous()){
4256         hci_release_packet_buffer();
4257         hci_emit_transport_packet_sent();
4258     }
4259 }
4260 #endif
4261 
4262 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4263     UNUSED(ds);
4264     hci_stack->substate = HCI_HALTING_CLOSE;
4265     // allow packet handlers to defer final shutdown
4266     hci_emit_state();
4267     hci_run();
4268 }
4269 
4270 static bool hci_run_acl_fragments(void){
4271     if (hci_stack->acl_fragmentation_total_size > 0u) {
4272         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4273         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4274         if (connection) {
4275             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4276                 hci_send_acl_packet_fragments(connection);
4277                 return true;
4278             }
4279         } else {
4280             // connection gone -> discard further fragments
4281             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4282             hci_stack->acl_fragmentation_total_size = 0;
4283             hci_stack->acl_fragmentation_pos = 0;
4284         }
4285     }
4286     return false;
4287 }
4288 
4289 #ifdef ENABLE_CLASSIC
4290 static bool hci_run_general_gap_classic(void){
4291 
4292     // assert stack is working and classic is active
4293     if (hci_classic_supported() == false)      return false;
4294     if (hci_stack->state != HCI_STATE_WORKING) return false;
4295 
4296     // decline incoming connections
4297     if (hci_stack->decline_reason){
4298         uint8_t reason = hci_stack->decline_reason;
4299         hci_stack->decline_reason = 0;
4300         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4301         return true;
4302     }
4303 
4304     if (hci_stack->gap_tasks != 0){
4305         hci_run_gap_tasks_classic();
4306         return true;
4307     }
4308 
4309     // start/stop inquiry
4310     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4311         uint8_t duration = hci_stack->inquiry_state;
4312         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4313         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4314         return true;
4315     }
4316     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4317         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4318         hci_send_cmd(&hci_inquiry_cancel);
4319         return true;
4320     }
4321     // remote name request
4322     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4323         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4324         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4325                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4326         return true;
4327     }
4328 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4329     // Local OOB data
4330     if (hci_stack->classic_read_local_oob_data){
4331         hci_stack->classic_read_local_oob_data = false;
4332         if (hci_stack->local_supported_commands[1] & 0x10u){
4333             hci_send_cmd(&hci_read_local_extended_oob_data);
4334         } else {
4335             hci_send_cmd(&hci_read_local_oob_data);
4336         }
4337     }
4338 #endif
4339     // pairing
4340     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4341         uint8_t state = hci_stack->gap_pairing_state;
4342         uint8_t pin_code[16];
4343         switch (state){
4344             case GAP_PAIRING_STATE_SEND_PIN:
4345                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4346                 memset(pin_code, 0, 16);
4347                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4348                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4349                 break;
4350             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4351                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4352                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4353                 break;
4354             case GAP_PAIRING_STATE_SEND_PASSKEY:
4355                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4356                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4357                 break;
4358             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4359                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4360                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4361                 break;
4362             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4363                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4364                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4365                 break;
4366             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4367                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4368                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4369                 break;
4370             default:
4371                 break;
4372         }
4373         return true;
4374     }
4375     return false;
4376 }
4377 #endif
4378 
4379 #ifdef ENABLE_BLE
4380 static bool hci_run_general_gap_le(void){
4381 
4382     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4383 
4384     if (hci_stack->state != HCI_STATE_WORKING) return false;
4385     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4386 
4387 
4388     // Phase 1: collect what to stop
4389 
4390     bool scanning_stop = false;
4391     bool connecting_stop = false;
4392     bool advertising_stop = false;
4393 
4394 #ifndef ENABLE_LE_CENTRAL
4395     UNUSED(scanning_stop);
4396     UNUSED(connecting_stop);
4397 #endif
4398 #ifndef ENABLE_LE_PERIPHERAL
4399     UNUSED(advertising_stop);
4400 #endif
4401 
4402     // check if own address changes
4403     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4404 
4405     // check if whitelist needs modification
4406     bool whitelist_modification_pending = false;
4407     btstack_linked_list_iterator_t lit;
4408     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4409     while (btstack_linked_list_iterator_has_next(&lit)){
4410         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4411         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4412             whitelist_modification_pending = true;
4413             break;
4414         }
4415     }
4416     // check if resolving list needs modification
4417     bool resolving_list_modification_pending = false;
4418 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4419     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4420 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4421         resolving_list_modification_pending = true;
4422     }
4423 #endif
4424 
4425 #ifdef ENABLE_LE_CENTRAL
4426     // scanning control
4427     if (hci_stack->le_scanning_active) {
4428         // stop if:
4429         // - parameter change required
4430         // - it's disabled
4431         // - whitelist change required but used for scanning
4432         // - resolving list modified
4433         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4434         if ((hci_stack->le_scanning_param_update) ||
4435             !hci_stack->le_scanning_enabled ||
4436             scanning_uses_whitelist ||
4437             resolving_list_modification_pending){
4438 
4439             scanning_stop = true;
4440         }
4441     }
4442 #endif
4443 
4444 #ifdef ENABLE_LE_CENTRAL
4445     // connecting control
4446     bool connecting_with_whitelist;
4447     switch (hci_stack->le_connecting_state){
4448         case LE_CONNECTING_DIRECT:
4449         case LE_CONNECTING_WHITELIST:
4450             // stop connecting if:
4451             // - connecting uses white and whitelist modification pending
4452             // - if it got disabled
4453             // - resolving list modified
4454             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4455             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4456                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4457                 resolving_list_modification_pending) {
4458 
4459                 connecting_stop = true;
4460             }
4461             break;
4462         default:
4463             break;
4464     }
4465 #endif
4466 
4467 #ifdef ENABLE_LE_PERIPHERAL
4468     // le advertisement control
4469     if (hci_stack->le_advertisements_active){
4470         // stop if:
4471         // - parameter change required
4472         // - random address used in advertising and changes
4473         // - it's disabled
4474         // - whitelist change required but used for advertisement filter policy
4475         // - resolving list modified
4476         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4477         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4478         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4479         if (advertising_change ||
4480             (advertising_uses_random_address && random_address_change) ||
4481             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4482             (advertising_uses_whitelist && whitelist_modification_pending) ||
4483             resolving_list_modification_pending) {
4484 
4485             advertising_stop = true;
4486         }
4487     }
4488 #endif
4489 
4490 
4491     // Phase 2: stop everything that should be off during modifications
4492 
4493 #ifdef ENABLE_LE_CENTRAL
4494     if (scanning_stop){
4495         hci_stack->le_scanning_active = false;
4496         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4497         return true;
4498     }
4499 #endif
4500 
4501 #ifdef ENABLE_LE_CENTRAL
4502     if (connecting_stop){
4503         hci_send_cmd(&hci_le_create_connection_cancel);
4504         return true;
4505     }
4506 #endif
4507 
4508 #ifdef ENABLE_LE_PERIPHERAL
4509     if (advertising_stop){
4510         hci_stack->le_advertisements_active = false;
4511         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4512         return true;
4513     }
4514 #endif
4515 
4516     // Phase 3: modify
4517 
4518     if (random_address_change){
4519         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4520         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4521         return true;
4522     }
4523 
4524 #ifdef ENABLE_LE_CENTRAL
4525     if (hci_stack->le_scanning_param_update){
4526         hci_stack->le_scanning_param_update = false;
4527         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4528                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4529         return true;
4530     }
4531 #endif
4532 
4533 #ifdef ENABLE_LE_PERIPHERAL
4534     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4535         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4536         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4537         hci_send_cmd(&hci_le_set_advertising_parameters,
4538                      hci_stack->le_advertisements_interval_min,
4539                      hci_stack->le_advertisements_interval_max,
4540                      hci_stack->le_advertisements_type,
4541                      hci_stack->le_advertisements_own_addr_type,
4542                      hci_stack->le_advertisements_direct_address_type,
4543                      hci_stack->le_advertisements_direct_address,
4544                      hci_stack->le_advertisements_channel_map,
4545                      hci_stack->le_advertisements_filter_policy);
4546         return true;
4547     }
4548     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4549         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4550         uint8_t adv_data_clean[31];
4551         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4552         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4553                      hci_stack->le_advertisements_data_len);
4554         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4555         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4556         return true;
4557     }
4558     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4559         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4560         uint8_t scan_data_clean[31];
4561         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4562         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4563                      hci_stack->le_scan_response_data_len);
4564         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4565         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4566         return true;
4567     }
4568 #endif
4569 
4570 
4571 #ifdef ENABLE_LE_CENTRAL
4572     // if connect with whitelist was active and is not cancelled yet, wait until next time
4573     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4574 #endif
4575 
4576     // LE Whitelist Management
4577     if (whitelist_modification_pending){
4578         // add/remove entries
4579         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4580         while (btstack_linked_list_iterator_has_next(&lit)){
4581             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4582 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4583 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4584 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4585 				return true;
4586 			}
4587             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4588 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4589                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4590                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4591                 return true;
4592             }
4593             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4594 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4595 				btstack_memory_whitelist_entry_free(entry);
4596             }
4597         }
4598     }
4599 
4600 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4601     // LE Resolving List Management
4602     if (resolving_list_supported) {
4603 		uint16_t i;
4604 		switch (hci_stack->le_resolving_list_state) {
4605 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4606 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4607 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4608 				return true;
4609 			case LE_RESOLVING_LIST_READ_SIZE:
4610 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4611 				hci_send_cmd(&hci_le_read_resolving_list_size);
4612 				return true;
4613 			case LE_RESOLVING_LIST_SEND_CLEAR:
4614 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4615 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4616 							  sizeof(hci_stack->le_resolving_list_add_entries));
4617 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4618 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4619 				hci_send_cmd(&hci_le_clear_resolving_list);
4620 				return true;
4621 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4622 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4623 					uint8_t offset = i >> 3;
4624 					uint8_t mask = 1 << (i & 7);
4625 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4626 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4627 					bd_addr_t peer_identity_addreses;
4628 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4629 					sm_key_t peer_irk;
4630 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4631 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4632 
4633 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4634 					// trigger whitelist entry 'update' (work around for controller bug)
4635 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4636 					while (btstack_linked_list_iterator_has_next(&lit)) {
4637 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4638 						if (entry->address_type != peer_identity_addr_type) continue;
4639 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4640 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4641 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4642 					}
4643 #endif
4644 
4645 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4646 								 peer_identity_addreses);
4647 					return true;
4648 				}
4649 
4650 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4651 
4652 				/* fall through */
4653 
4654 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4655 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4656 					uint8_t offset = i >> 3;
4657 					uint8_t mask = 1 << (i & 7);
4658 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4659 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4660 					bd_addr_t peer_identity_addreses;
4661 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4662 					sm_key_t peer_irk;
4663 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4664 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4665 					const uint8_t *local_irk = gap_get_persistent_irk();
4666 					// command uses format specifier 'P' that stores 16-byte value without flip
4667 					uint8_t local_irk_flipped[16];
4668 					uint8_t peer_irk_flipped[16];
4669 					reverse_128(local_irk, local_irk_flipped);
4670 					reverse_128(peer_irk, peer_irk_flipped);
4671 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4672 								 peer_irk_flipped, local_irk_flipped);
4673 					return true;
4674 				}
4675 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4676 				break;
4677 
4678 			default:
4679 				break;
4680 		}
4681 	}
4682     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4683 #endif
4684 
4685     // Phase 4: restore state
4686 
4687 #ifdef ENABLE_LE_CENTRAL
4688     // re-start scanning
4689     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4690         hci_stack->le_scanning_active = true;
4691         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4692         return true;
4693     }
4694 #endif
4695 
4696 #ifdef ENABLE_LE_CENTRAL
4697     // re-start connecting
4698     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4699         bd_addr_t null_addr;
4700         memset(null_addr, 0, 6);
4701         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4702         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4703         hci_send_cmd(&hci_le_create_connection,
4704                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4705                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4706                      1,         // use whitelist
4707                      0,         // peer address type
4708                      null_addr, // peer bd addr
4709                      hci_stack->le_connection_own_addr_type,   // our addr type:
4710                      hci_stack->le_connection_interval_min,    // conn interval min
4711                      hci_stack->le_connection_interval_max,    // conn interval max
4712                      hci_stack->le_connection_latency,         // conn latency
4713                      hci_stack->le_supervision_timeout,        // conn latency
4714                      hci_stack->le_minimum_ce_length,          // min ce length
4715                      hci_stack->le_maximum_ce_length           // max ce length
4716         );
4717         return true;
4718     }
4719 #endif
4720 
4721 #ifdef ENABLE_LE_PERIPHERAL
4722     // re-start advertising
4723     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4724         // check if advertisements should be enabled given
4725         hci_stack->le_advertisements_active = true;
4726         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4727         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4728         return true;
4729     }
4730 #endif
4731 
4732     return false;
4733 }
4734 #endif
4735 
4736 static bool hci_run_general_pending_commands(void){
4737     btstack_linked_item_t * it;
4738     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4739         hci_connection_t * connection = (hci_connection_t *) it;
4740 
4741         switch(connection->state){
4742             case SEND_CREATE_CONNECTION:
4743                 switch(connection->address_type){
4744 #ifdef ENABLE_CLASSIC
4745                     case BD_ADDR_TYPE_ACL:
4746                         log_info("sending hci_create_connection");
4747                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4748                         break;
4749 #endif
4750                     default:
4751 #ifdef ENABLE_BLE
4752 #ifdef ENABLE_LE_CENTRAL
4753                         log_info("sending hci_le_create_connection");
4754                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4755                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4756                         hci_send_cmd(&hci_le_create_connection,
4757                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4758                                      hci_stack->le_connection_scan_window,      // conn scan windows
4759                                      0,         // don't use whitelist
4760                                      connection->address_type, // peer address type
4761                                      connection->address,      // peer bd addr
4762                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4763                                      hci_stack->le_connection_interval_min,    // conn interval min
4764                                      hci_stack->le_connection_interval_max,    // conn interval max
4765                                      hci_stack->le_connection_latency,         // conn latency
4766                                      hci_stack->le_supervision_timeout,        // conn latency
4767                                      hci_stack->le_minimum_ce_length,          // min ce length
4768                                      hci_stack->le_maximum_ce_length          // max ce length
4769                         );
4770                         connection->state = SENT_CREATE_CONNECTION;
4771 #endif
4772 #endif
4773                         break;
4774                 }
4775                 return true;
4776 
4777 #ifdef ENABLE_CLASSIC
4778             case RECEIVED_CONNECTION_REQUEST:
4779                 connection->role  = HCI_ROLE_SLAVE;
4780                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4781                     log_info("sending hci_accept_connection_request");
4782                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4783                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4784                 }
4785                 return true;
4786 #endif
4787 
4788 #ifdef ENABLE_BLE
4789 #ifdef ENABLE_LE_CENTRAL
4790             case SEND_CANCEL_CONNECTION:
4791                 connection->state = SENT_CANCEL_CONNECTION;
4792                 hci_send_cmd(&hci_le_create_connection_cancel);
4793                 return true;
4794 #endif
4795 #endif
4796             case SEND_DISCONNECT:
4797                 connection->state = SENT_DISCONNECT;
4798                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4799                 return true;
4800 
4801             default:
4802                 break;
4803         }
4804 
4805         // no further commands if connection is about to get shut down
4806         if (connection->state == SENT_DISCONNECT) continue;
4807 
4808         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4809             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4810             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4811             return true;
4812         }
4813 
4814 #ifdef ENABLE_CLASSIC
4815 
4816         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4817             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4818             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4819             return true;
4820         }
4821 
4822         // Handling link key request requires remote supported features
4823         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4824             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4825             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4826 
4827             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4828             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4829             if (have_link_key && security_level_sufficient){
4830                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4831             } else {
4832                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4833             }
4834             return true;
4835         }
4836 
4837         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4838             log_info("denying to pin request");
4839             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4840             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4841             return true;
4842         }
4843 
4844         // security assessment requires remote features
4845         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4846             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4847             hci_ssp_assess_security_on_io_cap_request(connection);
4848             // 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
4849         }
4850 
4851         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4852             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4853             // set authentication requirements:
4854             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4855             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4856             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4857             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4858                 authreq |= 1;
4859             }
4860             bool bonding = hci_stack->bondable;
4861             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4862                 // if we have received IO Cap Response, we're in responder role
4863                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4864                 if (bonding && !remote_bonding){
4865                     log_info("Remote not bonding, dropping local flag");
4866                     bonding = false;
4867                 }
4868             }
4869             if (bonding){
4870                 if (connection->bonding_flags & BONDING_DEDICATED){
4871                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4872                 } else {
4873                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4874                 }
4875             }
4876             uint8_t have_oob_data = 0;
4877 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4878             if (connection->classic_oob_c_192 != NULL){
4879                     have_oob_data |= 1;
4880             }
4881             if (connection->classic_oob_c_256 != NULL){
4882                 have_oob_data |= 2;
4883             }
4884 #endif
4885             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4886             return true;
4887         }
4888 
4889         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4890             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4891             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4892             return true;
4893         }
4894 
4895 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4896         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4897             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4898             const uint8_t zero[16] = { 0 };
4899             const uint8_t * r_192 = zero;
4900             const uint8_t * c_192 = zero;
4901             const uint8_t * r_256 = zero;
4902             const uint8_t * c_256 = zero;
4903             // verify P-256 OOB
4904             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4905                 c_256 = connection->classic_oob_c_256;
4906                 if (connection->classic_oob_r_256 != NULL) {
4907                     r_256 = connection->classic_oob_r_256;
4908                 }
4909             }
4910             // verify P-192 OOB
4911             if ((connection->classic_oob_c_192 != NULL)) {
4912                 c_192 = connection->classic_oob_c_192;
4913                 if (connection->classic_oob_r_192 != NULL) {
4914                     r_192 = connection->classic_oob_r_192;
4915                 }
4916             }
4917 
4918             // assess security
4919             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4920             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4921             if (need_level_4 && !can_reach_level_4){
4922                 log_info("Level 4 required, but not possible -> abort");
4923                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4924                 // send oob negative reply
4925                 c_256 = NULL;
4926                 c_192 = NULL;
4927             }
4928 
4929             // Reply
4930             if (c_256 != zero) {
4931                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4932             } else if (c_192 != zero){
4933                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4934             } else {
4935                 hci_stack->classic_oob_con_handle = connection->con_handle;
4936                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4937             }
4938             return true;
4939         }
4940 #endif
4941 
4942         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4943             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4944             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4945             return true;
4946         }
4947 
4948         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4949             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4950             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4951             return true;
4952         }
4953 
4954         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4955             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4956             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4957             return true;
4958         }
4959 
4960         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4961             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4962             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4963             connection->state = SENT_DISCONNECT;
4964             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4965             return true;
4966         }
4967 
4968         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4969             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4970             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4971             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4972             return true;
4973         }
4974 
4975         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4976             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4977             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4978             return true;
4979         }
4980 
4981         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4982             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4983             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4984             return true;
4985         }
4986 
4987         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4988             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4989             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4990             return true;
4991         }
4992 
4993         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4994             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4995             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4996             return true;
4997         }
4998 
4999         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
5000             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
5001             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
5002             return true;
5003         }
5004 #endif
5005 
5006         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
5007             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
5008 #ifdef ENABLE_CLASSIC
5009             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
5010 #endif
5011             if (connection->state != SENT_DISCONNECT){
5012                 connection->state = SENT_DISCONNECT;
5013                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
5014                 return true;
5015             }
5016         }
5017 
5018 #ifdef ENABLE_CLASSIC
5019         uint16_t sniff_min_interval;
5020         switch (connection->sniff_min_interval){
5021             case 0:
5022                 break;
5023             case 0xffff:
5024                 connection->sniff_min_interval = 0;
5025                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
5026                 return true;
5027             default:
5028                 sniff_min_interval = connection->sniff_min_interval;
5029                 connection->sniff_min_interval = 0;
5030                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
5031                 return true;
5032         }
5033 
5034         if (connection->sniff_subrating_max_latency != 0xffff){
5035             uint16_t max_latency = connection->sniff_subrating_max_latency;
5036             connection->sniff_subrating_max_latency = 0;
5037             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
5038             return true;
5039         }
5040 
5041         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
5042             uint8_t service_type = (uint8_t) connection->qos_service_type;
5043             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
5044             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);
5045             return true;
5046         }
5047 
5048         if (connection->request_role != HCI_ROLE_INVALID){
5049             hci_role_t role = connection->request_role;
5050             connection->request_role = HCI_ROLE_INVALID;
5051             hci_send_cmd(&hci_switch_role_command, connection->address, role);
5052             return true;
5053         }
5054 #endif
5055 
5056 #ifdef ENABLE_BLE
5057         switch (connection->le_con_parameter_update_state){
5058             // response to L2CAP CON PARAMETER UPDATE REQUEST
5059             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
5060                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5061                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
5062                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5063                              0x0000, 0xffff);
5064                 return true;
5065             case CON_PARAMETER_UPDATE_REPLY:
5066                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5067                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
5068                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5069                              0x0000, 0xffff);
5070                 return true;
5071             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
5072                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5073                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
5074                 return true;
5075             default:
5076                 break;
5077         }
5078         if (connection->le_phy_update_all_phys != 0xffu){
5079             uint8_t all_phys = connection->le_phy_update_all_phys;
5080             connection->le_phy_update_all_phys = 0xff;
5081             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);
5082             return true;
5083         }
5084 #endif
5085     }
5086     return false;
5087 }
5088 
5089 static void hci_run(void){
5090 
5091     // stack state sub statemachines
5092     // halting needs to be called even if we cannot send command packet now
5093     switch (hci_stack->state) {
5094         case HCI_STATE_INITIALIZING:
5095             hci_initializing_run();
5096             break;
5097         case HCI_STATE_HALTING:
5098             hci_halting_run();
5099             break;
5100         case HCI_STATE_FALLING_ASLEEP:
5101             hci_falling_asleep_run();
5102             break;
5103         default:
5104             break;
5105     }
5106 
5107     bool done;
5108 
5109     // send continuation fragments first, as they block the prepared packet buffer
5110     done = hci_run_acl_fragments();
5111     if (done) return;
5112 
5113 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
5114     // send host num completed packets next as they don't require num_cmd_packets > 0
5115     if (!hci_can_send_comand_packet_transport()) return;
5116     if (hci_stack->host_completed_packets){
5117         hci_host_num_completed_packets();
5118         return;
5119     }
5120 #endif
5121 
5122     if (!hci_can_send_command_packet_now()) return;
5123 
5124     // global/non-connection oriented commands
5125 
5126 
5127 #ifdef ENABLE_CLASSIC
5128     // general gap classic
5129     done = hci_run_general_gap_classic();
5130     if (done) return;
5131 #endif
5132 
5133 #ifdef ENABLE_BLE
5134     // general gap le
5135     done = hci_run_general_gap_le();
5136     if (done) return;
5137 #endif
5138 
5139     // send pending HCI commands
5140     hci_run_general_pending_commands();
5141 }
5142 
5143 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5144     // house-keeping
5145 
5146 #ifdef ENABLE_CLASSIC
5147     bd_addr_t addr;
5148     hci_connection_t * conn;
5149 #endif
5150 #ifdef ENABLE_LE_CENTRAL
5151     uint8_t initiator_filter_policy;
5152 #endif
5153 
5154     uint16_t opcode = little_endian_read_16(packet, 0);
5155     switch (opcode) {
5156         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5157             hci_stack->loopback_mode = packet[3];
5158             break;
5159 
5160 #ifdef ENABLE_CLASSIC
5161         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5162             reverse_bd_addr(&packet[3], addr);
5163             log_info("Create_connection to %s", bd_addr_to_str(addr));
5164 
5165             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5166             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5167                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5168                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5169             }
5170 
5171             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5172             if (!conn) {
5173                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5174                 if (!conn) {
5175                     // notify client that alloc failed
5176                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5177                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5178                 }
5179                 conn->state = SEND_CREATE_CONNECTION;
5180                 conn->role  = HCI_ROLE_MASTER;
5181             }
5182 
5183             conn->con_handle = HCI_CON_HANDLE_INVALID;
5184             conn->role = HCI_ROLE_INVALID;
5185 
5186             log_info("conn state %u", conn->state);
5187             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5188             switch (conn->state) {
5189                 // if connection active exists
5190                 case OPEN:
5191                     // and OPEN, emit connection complete command
5192                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5193                     // packet not sent to controller
5194                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5195                 case RECEIVED_DISCONNECTION_COMPLETE:
5196                     // create connection triggered in disconnect complete event, let's do it now
5197                     break;
5198                 case SEND_CREATE_CONNECTION:
5199                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5200                     break;
5201                 default:
5202                     // otherwise, just ignore as it is already in the open process
5203                     // packet not sent to controller
5204                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5205             }
5206             conn->state = SENT_CREATE_CONNECTION;
5207 
5208             // track outgoing connection
5209             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5210             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5211             break;
5212 
5213 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5214         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5215             // setup_synchronous_connection? Voice setting at offset 22
5216             // TODO: compare to current setting if sco connection already active
5217             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5218             break;
5219         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5220             // accept_synchronous_connection? Voice setting at offset 18
5221             // TODO: compare to current setting if sco connection already active
5222             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5223             break;
5224 #endif
5225 #endif
5226 
5227 #ifdef ENABLE_BLE
5228 #ifdef ENABLE_LE_CENTRAL
5229         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5230             // white list used?
5231             initiator_filter_policy = packet[7];
5232             switch (initiator_filter_policy) {
5233                 case 0:
5234                     // whitelist not used
5235                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5236                     break;
5237                 case 1:
5238                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5239                     break;
5240                 default:
5241                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5242                     break;
5243             }
5244             // track outgoing connection
5245             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5246             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5247             break;
5248         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5249             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5250             break;
5251 #endif
5252 #endif
5253         default:
5254             break;
5255     }
5256 
5257     hci_stack->num_cmd_packets--;
5258 
5259     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5260     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5261     if (err != 0){
5262         return ERROR_CODE_HARDWARE_FAILURE;
5263     }
5264     return ERROR_CODE_SUCCESS;
5265 }
5266 
5267 // disconnect because of security block
5268 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5269     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5270     if (!connection) return;
5271     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5272 }
5273 
5274 
5275 // Configure Secure Simple Pairing
5276 
5277 #ifdef ENABLE_CLASSIC
5278 
5279 // enable will enable SSP during init
5280 void gap_ssp_set_enable(int enable){
5281     hci_stack->ssp_enable = enable;
5282 }
5283 
5284 static int hci_local_ssp_activated(void){
5285     return gap_ssp_supported() && hci_stack->ssp_enable;
5286 }
5287 
5288 // if set, BTstack will respond to io capability request using authentication requirement
5289 void gap_ssp_set_io_capability(int io_capability){
5290     hci_stack->ssp_io_capability = io_capability;
5291 }
5292 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5293     hci_stack->ssp_authentication_requirement = authentication_requirement;
5294 }
5295 
5296 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5297 void gap_ssp_set_auto_accept(int auto_accept){
5298     hci_stack->ssp_auto_accept = auto_accept;
5299 }
5300 
5301 void gap_secure_connections_enable(bool enable){
5302     hci_stack->secure_connections_enable = enable;
5303 }
5304 
5305 #endif
5306 
5307 // va_list part of hci_send_cmd
5308 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5309     if (!hci_can_send_command_packet_now()){
5310         log_error("hci_send_cmd called but cannot send packet now");
5311         return ERROR_CODE_COMMAND_DISALLOWED;
5312     }
5313 
5314     // for HCI INITIALIZATION
5315     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5316     hci_stack->last_cmd_opcode = cmd->opcode;
5317 
5318     hci_reserve_packet_buffer();
5319     uint8_t * packet = hci_stack->hci_packet_buffer;
5320     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5321     uint8_t status = hci_send_cmd_packet(packet, size);
5322 
5323     // release packet buffer on error or for synchronous transport implementations
5324     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5325         hci_release_packet_buffer();
5326         hci_emit_transport_packet_sent();
5327     }
5328 
5329     return status;
5330 }
5331 
5332 /**
5333  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5334  */
5335 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5336     va_list argptr;
5337     va_start(argptr, cmd);
5338     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5339     va_end(argptr);
5340     return status;
5341 }
5342 
5343 // Create various non-HCI events.
5344 // TODO: generalize, use table similar to hci_create_command
5345 
5346 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5347     // dump packet
5348     if (dump) {
5349         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5350     }
5351 
5352     // dispatch to all event handlers
5353     btstack_linked_list_iterator_t it;
5354     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5355     while (btstack_linked_list_iterator_has_next(&it)){
5356         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5357         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5358     }
5359 }
5360 
5361 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5362     if (!hci_stack->acl_packet_handler) return;
5363     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5364 }
5365 
5366 #ifdef ENABLE_CLASSIC
5367 static void hci_notify_if_sco_can_send_now(void){
5368     // notify SCO sender if waiting
5369     if (!hci_stack->sco_waiting_for_can_send_now) return;
5370     if (hci_can_send_sco_packet_now()){
5371         hci_stack->sco_waiting_for_can_send_now = 0;
5372         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5373         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5374         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5375     }
5376 }
5377 
5378 // parsing end emitting has been merged to reduce code size
5379 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5380     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5381 
5382     uint8_t * eir_data;
5383     ad_context_t context;
5384     const uint8_t * name;
5385     uint8_t         name_len;
5386 
5387     if (size < 3) return;
5388 
5389     int event_type = hci_event_packet_get_type(packet);
5390     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5391     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5392 
5393     switch (event_type){
5394         case HCI_EVENT_INQUIRY_RESULT:
5395         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5396             if (size != (3 + (num_responses * 14))) return;
5397             break;
5398         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5399             if (size != 257) return;
5400             if (num_responses != 1) return;
5401             break;
5402         default:
5403             return;
5404     }
5405 
5406     // event[1] is set at the end
5407     int i;
5408     for (i=0; i<num_responses;i++){
5409         memset(event, 0, sizeof(event));
5410         event[0] = GAP_EVENT_INQUIRY_RESULT;
5411         uint8_t event_size = 27;    // if name is not set by EIR
5412 
5413         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5414         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5415         (void)memcpy(&event[9],
5416                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5417                      3); // class of device
5418         (void)memcpy(&event[12],
5419                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5420                      2); // clock offset
5421 
5422         switch (event_type){
5423             case HCI_EVENT_INQUIRY_RESULT:
5424                 // 14,15,16,17 = 0, size 18
5425                 break;
5426             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5427                 event[14] = 1;
5428                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5429                 // 16,17 = 0, size 18
5430                 break;
5431             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5432                 event[14] = 1;
5433                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5434                 // EIR packets only contain a single inquiry response
5435                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5436                 name = NULL;
5437                 // Iterate over EIR data
5438                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5439                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5440                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5441                     const uint8_t * data = ad_iterator_get_data(&context);
5442                     // Prefer Complete Local Name over Shortened Local Name
5443                     switch (data_type){
5444                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5445                             if (name) continue;
5446                             /* fall through */
5447                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5448                             name = data;
5449                             name_len = data_size;
5450                             break;
5451                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5452                             if (data_size != 8) break;
5453                             event[16] = 1;
5454                             memcpy(&event[17], data, 8);
5455                             break;
5456                         default:
5457                             break;
5458                     }
5459                 }
5460                 if (name){
5461                     event[25] = 1;
5462                     // truncate name if needed
5463                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5464                     event[26] = len;
5465                     (void)memcpy(&event[27], name, len);
5466                     event_size += len;
5467                 }
5468                 break;
5469             default:
5470                 return;
5471         }
5472         event[1] = event_size - 2;
5473         hci_emit_event(event, event_size, 1);
5474     }
5475 }
5476 #endif
5477 
5478 void hci_emit_state(void){
5479     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5480     uint8_t event[3];
5481     event[0] = BTSTACK_EVENT_STATE;
5482     event[1] = sizeof(event) - 2u;
5483     event[2] = hci_stack->state;
5484     hci_emit_event(event, sizeof(event), 1);
5485 }
5486 
5487 #ifdef ENABLE_CLASSIC
5488 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5489     uint8_t event[13];
5490     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5491     event[1] = sizeof(event) - 2;
5492     event[2] = status;
5493     little_endian_store_16(event, 3, con_handle);
5494     reverse_bd_addr(address, &event[5]);
5495     event[11] = 1; // ACL connection
5496     event[12] = 0; // encryption disabled
5497     hci_emit_event(event, sizeof(event), 1);
5498 }
5499 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5500     if (disable_l2cap_timeouts) return;
5501     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5502     uint8_t event[4];
5503     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5504     event[1] = sizeof(event) - 2;
5505     little_endian_store_16(event, 2, conn->con_handle);
5506     hci_emit_event(event, sizeof(event), 1);
5507 }
5508 #endif
5509 
5510 #ifdef ENABLE_BLE
5511 #ifdef ENABLE_LE_CENTRAL
5512 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){
5513     uint8_t event[21];
5514     event[0] = HCI_EVENT_LE_META;
5515     event[1] = sizeof(event) - 2u;
5516     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5517     event[3] = status;
5518     little_endian_store_16(event, 4, con_handle);
5519     event[6] = 0; // TODO: role
5520     event[7] = address_type;
5521     reverse_bd_addr(address, &event[8]);
5522     little_endian_store_16(event, 14, 0); // interval
5523     little_endian_store_16(event, 16, 0); // latency
5524     little_endian_store_16(event, 18, 0); // supervision timeout
5525     event[20] = 0; // master clock accuracy
5526     hci_emit_event(event, sizeof(event), 1);
5527 }
5528 #endif
5529 #endif
5530 
5531 static void hci_emit_transport_packet_sent(void){
5532     // notify upper stack that it might be possible to send again
5533     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5534     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5535 }
5536 
5537 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5538     uint8_t event[6];
5539     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5540     event[1] = sizeof(event) - 2u;
5541     event[2] = 0; // status = OK
5542     little_endian_store_16(event, 3, con_handle);
5543     event[5] = reason;
5544     hci_emit_event(event, sizeof(event), 1);
5545 }
5546 
5547 static void hci_emit_nr_connections_changed(void){
5548     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5549     uint8_t event[3];
5550     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5551     event[1] = sizeof(event) - 2u;
5552     event[2] = nr_hci_connections();
5553     hci_emit_event(event, sizeof(event), 1);
5554 }
5555 
5556 static void hci_emit_hci_open_failed(void){
5557     log_info("BTSTACK_EVENT_POWERON_FAILED");
5558     uint8_t event[2];
5559     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5560     event[1] = sizeof(event) - 2u;
5561     hci_emit_event(event, sizeof(event), 1);
5562 }
5563 
5564 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5565     log_info("hci_emit_dedicated_bonding_result %u ", status);
5566     uint8_t event[9];
5567     int pos = 0;
5568     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5569     event[pos++] = sizeof(event) - 2u;
5570     event[pos++] = status;
5571     reverse_bd_addr(address, &event[pos]);
5572     hci_emit_event(event, sizeof(event), 1);
5573 }
5574 
5575 
5576 #ifdef ENABLE_CLASSIC
5577 
5578 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5579     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5580     uint8_t event[5];
5581     int pos = 0;
5582     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5583     event[pos++] = sizeof(event) - 2;
5584     little_endian_store_16(event, 2, con_handle);
5585     pos += 2;
5586     event[pos++] = level;
5587     hci_emit_event(event, sizeof(event), 1);
5588 }
5589 
5590 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5591     if (!connection) return LEVEL_0;
5592     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5593     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5594     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5595     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5596     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5597     // LEVEL 4 always requires 128 bit encrytion key size
5598     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5599         security_level = LEVEL_3;
5600     }
5601     return security_level;
5602 }
5603 
5604 static void hci_emit_discoverable_enabled(uint8_t enabled){
5605     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5606     uint8_t event[3];
5607     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5608     event[1] = sizeof(event) - 2;
5609     event[2] = enabled;
5610     hci_emit_event(event, sizeof(event), 1);
5611 }
5612 
5613 // query if remote side supports eSCO
5614 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5615     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5616     if (!connection) return false;
5617     return (connection->remote_supported_features[0] & 1) != 0;
5618 }
5619 
5620 static bool hci_ssp_supported(hci_connection_t * connection){
5621     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5622     return (connection->bonding_flags & mask) == mask;
5623 }
5624 
5625 // query if remote side supports SSP
5626 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5627     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5628     if (!connection) return false;
5629     return hci_ssp_supported(connection) ? 1 : 0;
5630 }
5631 
5632 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5633     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5634 }
5635 
5636 /**
5637  * Check if remote supported features query has completed
5638  */
5639 bool hci_remote_features_available(hci_con_handle_t handle){
5640     hci_connection_t * connection = hci_connection_for_handle(handle);
5641     if (!connection) return false;
5642     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5643 }
5644 
5645 /**
5646  * Trigger remote supported features query
5647  */
5648 
5649 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection){
5650     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) == 0){
5651         connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5652     }
5653 }
5654 
5655 void hci_remote_features_query(hci_con_handle_t con_handle){
5656     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5657     if (!connection) return;
5658     hci_trigger_remote_features_for_connection(connection);
5659     hci_run();
5660 }
5661 
5662 // GAP API
5663 /**
5664  * @bbrief enable/disable bonding. default is enabled
5665  * @praram enabled
5666  */
5667 void gap_set_bondable_mode(int enable){
5668     hci_stack->bondable = enable ? 1 : 0;
5669 }
5670 /**
5671  * @brief Get bondable mode.
5672  * @return 1 if bondable
5673  */
5674 int gap_get_bondable_mode(void){
5675     return hci_stack->bondable;
5676 }
5677 
5678 /**
5679  * @brief map link keys to security levels
5680  */
5681 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5682     switch (link_key_type){
5683         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5684             return LEVEL_4;
5685         case COMBINATION_KEY:
5686         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5687             return LEVEL_3;
5688         default:
5689             return LEVEL_2;
5690     }
5691 }
5692 
5693 /**
5694  * @brief map link keys to secure connection yes/no
5695  */
5696 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5697     switch (link_key_type){
5698         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5699         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5700             return 1;
5701         default:
5702             return 0;
5703     }
5704 }
5705 
5706 /**
5707  * @brief map link keys to authenticated
5708  */
5709 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5710     switch (link_key_type){
5711         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5712         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5713             return 1;
5714         default:
5715             return 0;
5716     }
5717 }
5718 
5719 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5720     log_info("gap_mitm_protection_required_for_security_level %u", level);
5721     return level > LEVEL_2;
5722 }
5723 
5724 /**
5725  * @brief get current security level
5726  */
5727 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5728     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5729     if (!connection) return LEVEL_0;
5730     return gap_security_level_for_connection(connection);
5731 }
5732 
5733 /**
5734  * @brief request connection to device to
5735  * @result GAP_AUTHENTICATION_RESULT
5736  */
5737 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5738     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5739     if (!connection){
5740         hci_emit_security_level(con_handle, LEVEL_0);
5741         return;
5742     }
5743 
5744     btstack_assert(hci_is_le_connection(connection) == false);
5745 
5746     // 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)
5747     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5748     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5749         requested_level = LEVEL_4;
5750     }
5751 
5752     gap_security_level_t current_level = gap_security_level(con_handle);
5753     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5754         requested_level, connection->requested_security_level, current_level);
5755 
5756     // authentication active if authentication request was sent or planned level > 0
5757     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5758     if (authentication_active){
5759         // authentication already active
5760         if (connection->requested_security_level < requested_level){
5761             // increase requested level as new level is higher
5762             // TODO: handle re-authentication when done
5763             connection->requested_security_level = requested_level;
5764         }
5765     } else {
5766         // no request active, notify if security sufficient
5767         if (requested_level <= current_level){
5768             hci_emit_security_level(con_handle, current_level);
5769             return;
5770         }
5771 
5772         // store request
5773         connection->requested_security_level = requested_level;
5774 
5775         // request remote features if not already active
5776         hci_remote_features_query(con_handle);
5777 
5778         // start to authenticate connection
5779         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5780         hci_run();
5781     }
5782 }
5783 
5784 /**
5785  * @brief start dedicated bonding with device. disconnect after bonding
5786  * @param device
5787  * @param request MITM protection
5788  * @result GAP_DEDICATED_BONDING_COMPLETE
5789  */
5790 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5791 
5792     // create connection state machine
5793     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5794 
5795     if (!connection){
5796         return BTSTACK_MEMORY_ALLOC_FAILED;
5797     }
5798 
5799     // delete linkn key
5800     gap_drop_link_key_for_bd_addr(device);
5801 
5802     // configure LEVEL_2/3, dedicated bonding
5803     connection->state = SEND_CREATE_CONNECTION;
5804     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5805     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5806     connection->bonding_flags = BONDING_DEDICATED;
5807 
5808     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5809 
5810     // handle: connnection failure (connection complete != ok)
5811     // handle: authentication failure
5812     // handle: disconnect on done
5813 
5814     hci_run();
5815 
5816     return 0;
5817 }
5818 
5819 void gap_set_local_name(const char * local_name){
5820     hci_stack->local_name = local_name;
5821     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5822     // also update EIR if not set by user
5823     if (hci_stack->eir_data == NULL){
5824         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5825     }
5826     hci_run();
5827 }
5828 #endif
5829 
5830 
5831 #ifdef ENABLE_BLE
5832 
5833 #ifdef ENABLE_LE_CENTRAL
5834 void gap_start_scan(void){
5835     hci_stack->le_scanning_enabled = true;
5836     hci_run();
5837 }
5838 
5839 void gap_stop_scan(void){
5840     hci_stack->le_scanning_enabled = false;
5841     hci_run();
5842 }
5843 
5844 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5845     hci_stack->le_scan_type          = scan_type;
5846     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5847     hci_stack->le_scan_interval      = scan_interval;
5848     hci_stack->le_scan_window        = scan_window;
5849     hci_stack->le_scanning_param_update = true;
5850     hci_run();
5851 }
5852 
5853 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5854     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5855 }
5856 
5857 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5858     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5859     if (!conn){
5860         // disallow if le connection is already outgoing
5861         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5862             log_error("le connection already active");
5863             return ERROR_CODE_COMMAND_DISALLOWED;
5864         }
5865 
5866         log_info("gap_connect: no connection exists yet, creating context");
5867         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5868         if (!conn){
5869             // notify client that alloc failed
5870             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5871             log_info("gap_connect: failed to alloc hci_connection_t");
5872             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5873         }
5874 
5875         // set le connecting state
5876         if (hci_is_le_connection_type(addr_type)){
5877             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5878         }
5879 
5880         conn->state = SEND_CREATE_CONNECTION;
5881         log_info("gap_connect: send create connection next");
5882         hci_run();
5883         return ERROR_CODE_SUCCESS;
5884     }
5885 
5886     if (!hci_is_le_connection(conn) ||
5887         (conn->state == SEND_CREATE_CONNECTION) ||
5888         (conn->state == SENT_CREATE_CONNECTION)) {
5889         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5890         log_error("gap_connect: classic connection or connect is already being created");
5891         return GATT_CLIENT_IN_WRONG_STATE;
5892     }
5893 
5894     // check if connection was just disconnected
5895     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5896         log_info("gap_connect: send create connection (again)");
5897         conn->state = SEND_CREATE_CONNECTION;
5898         hci_run();
5899         return ERROR_CODE_SUCCESS;
5900     }
5901 
5902     log_info("gap_connect: context exists with state %u", conn->state);
5903     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5904     hci_run();
5905     return ERROR_CODE_SUCCESS;
5906 }
5907 
5908 // @assumption: only a single outgoing LE Connection exists
5909 static hci_connection_t * gap_get_outgoing_connection(void){
5910     btstack_linked_item_t *it;
5911     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5912         hci_connection_t * conn = (hci_connection_t *) it;
5913         if (!hci_is_le_connection(conn)) continue;
5914         switch (conn->state){
5915             case SEND_CREATE_CONNECTION:
5916             case SENT_CREATE_CONNECTION:
5917             case SENT_CANCEL_CONNECTION:
5918                 return conn;
5919             default:
5920                 break;
5921         };
5922     }
5923     return NULL;
5924 }
5925 
5926 uint8_t gap_connect_cancel(void){
5927     hci_connection_t * conn = gap_get_outgoing_connection();
5928     if (!conn) return 0;
5929     switch (conn->state){
5930         case SEND_CREATE_CONNECTION:
5931             // skip sending create connection and emit event instead
5932             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5933             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5934             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5935             btstack_memory_hci_connection_free( conn );
5936             break;
5937         case SENT_CREATE_CONNECTION:
5938             // request to send cancel connection
5939             conn->state = SEND_CANCEL_CONNECTION;
5940             hci_run();
5941             break;
5942         default:
5943             break;
5944     }
5945     return 0;
5946 }
5947 #endif
5948 
5949 #ifdef ENABLE_LE_CENTRAL
5950 /**
5951  * @brief Set connection parameters for outgoing connections
5952  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5953  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5954  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5955  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5956  * @param conn_latency, default: 4
5957  * @param supervision_timeout (unit: 10ms), default: 720 ms
5958  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5959  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5960  */
5961 
5962 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5963     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5964     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5965     hci_stack->le_connection_scan_interval = conn_scan_interval;
5966     hci_stack->le_connection_scan_window = conn_scan_window;
5967     hci_stack->le_connection_interval_min = conn_interval_min;
5968     hci_stack->le_connection_interval_max = conn_interval_max;
5969     hci_stack->le_connection_latency = conn_latency;
5970     hci_stack->le_supervision_timeout = supervision_timeout;
5971     hci_stack->le_minimum_ce_length = min_ce_length;
5972     hci_stack->le_maximum_ce_length = max_ce_length;
5973 }
5974 #endif
5975 
5976 /**
5977  * @brief Updates the connection parameters for a given LE connection
5978  * @param handle
5979  * @param conn_interval_min (unit: 1.25ms)
5980  * @param conn_interval_max (unit: 1.25ms)
5981  * @param conn_latency
5982  * @param supervision_timeout (unit: 10ms)
5983  * @return 0 if ok
5984  */
5985 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5986     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5987     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5988     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5989     connection->le_conn_interval_min = conn_interval_min;
5990     connection->le_conn_interval_max = conn_interval_max;
5991     connection->le_conn_latency = conn_latency;
5992     connection->le_supervision_timeout = supervision_timeout;
5993     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5994     hci_run();
5995     return 0;
5996 }
5997 
5998 /**
5999  * @brief Request an update of the connection parameter for a given LE connection
6000  * @param handle
6001  * @param conn_interval_min (unit: 1.25ms)
6002  * @param conn_interval_max (unit: 1.25ms)
6003  * @param conn_latency
6004  * @param supervision_timeout (unit: 10ms)
6005  * @return 0 if ok
6006  */
6007 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
6008     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
6009     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6010     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6011     connection->le_conn_interval_min = conn_interval_min;
6012     connection->le_conn_interval_max = conn_interval_max;
6013     connection->le_conn_latency = conn_latency;
6014     connection->le_supervision_timeout = supervision_timeout;
6015     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
6016     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
6017     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
6018     return 0;
6019 }
6020 
6021 #ifdef ENABLE_LE_PERIPHERAL
6022 
6023 /**
6024  * @brief Set Advertisement Data
6025  * @param advertising_data_length
6026  * @param advertising_data (max 31 octets)
6027  * @note data is not copied, pointer has to stay valid
6028  */
6029 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6030     hci_stack->le_advertisements_data_len = advertising_data_length;
6031     hci_stack->le_advertisements_data = advertising_data;
6032     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6033     hci_run();
6034 }
6035 
6036 /**
6037  * @brief Set Scan Response Data
6038  * @param advertising_data_length
6039  * @param advertising_data (max 31 octets)
6040  * @note data is not copied, pointer has to stay valid
6041  */
6042 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6043     hci_stack->le_scan_response_data_len = scan_response_data_length;
6044     hci_stack->le_scan_response_data = scan_response_data;
6045     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6046     hci_run();
6047 }
6048 
6049 /**
6050  * @brief Set Advertisement Parameters
6051  * @param adv_int_min
6052  * @param adv_int_max
6053  * @param adv_type
6054  * @param direct_address_type
6055  * @param direct_address
6056  * @param channel_map
6057  * @param filter_policy
6058  *
6059  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6060  */
6061  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6062     uint8_t direct_address_typ, bd_addr_t direct_address,
6063     uint8_t channel_map, uint8_t filter_policy) {
6064 
6065     hci_stack->le_advertisements_interval_min = adv_int_min;
6066     hci_stack->le_advertisements_interval_max = adv_int_max;
6067     hci_stack->le_advertisements_type = adv_type;
6068     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6069     hci_stack->le_advertisements_channel_map = channel_map;
6070     hci_stack->le_advertisements_filter_policy = filter_policy;
6071     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6072                  6);
6073 
6074     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6075     hci_run();
6076  }
6077 
6078 /**
6079  * @brief Enable/Disable Advertisements
6080  * @param enabled
6081  */
6082 void gap_advertisements_enable(int enabled){
6083     hci_stack->le_advertisements_enabled = enabled != 0;
6084     hci_update_advertisements_enabled_for_current_roles();
6085     hci_run();
6086 }
6087 
6088 #endif
6089 
6090 void hci_le_set_own_address_type(uint8_t own_address_type){
6091     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6092     if (own_address_type == hci_stack->le_own_addr_type) return;
6093     hci_stack->le_own_addr_type = own_address_type;
6094 
6095 #ifdef ENABLE_LE_PERIPHERAL
6096     // update advertisement parameters, too
6097     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6098     hci_run();
6099 #endif
6100 #ifdef ENABLE_LE_CENTRAL
6101     // note: we don't update scan parameters or modify ongoing connection attempts
6102 #endif
6103 }
6104 
6105 void hci_le_random_address_set(const bd_addr_t random_address){
6106     memcpy(hci_stack->le_random_address, random_address, 6);
6107     hci_stack->le_random_address_set = true;
6108     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6109     hci_run();
6110 }
6111 
6112 #endif
6113 
6114 uint8_t gap_disconnect(hci_con_handle_t handle){
6115     hci_connection_t * conn = hci_connection_for_handle(handle);
6116     if (!conn){
6117         hci_emit_disconnection_complete(handle, 0);
6118         return 0;
6119     }
6120     // ignore if already disconnected
6121     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6122         return 0;
6123     }
6124     conn->state = SEND_DISCONNECT;
6125     hci_run();
6126     return 0;
6127 }
6128 
6129 int gap_read_rssi(hci_con_handle_t con_handle){
6130     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6131     if (hci_connection == NULL) return 0;
6132     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6133     hci_run();
6134     return 1;
6135 }
6136 
6137 /**
6138  * @brief Get connection type
6139  * @param con_handle
6140  * @result connection_type
6141  */
6142 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6143     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6144     if (!conn) return GAP_CONNECTION_INVALID;
6145     switch (conn->address_type){
6146         case BD_ADDR_TYPE_LE_PUBLIC:
6147         case BD_ADDR_TYPE_LE_RANDOM:
6148             return GAP_CONNECTION_LE;
6149         case BD_ADDR_TYPE_SCO:
6150             return GAP_CONNECTION_SCO;
6151         case BD_ADDR_TYPE_ACL:
6152             return GAP_CONNECTION_ACL;
6153         default:
6154             return GAP_CONNECTION_INVALID;
6155     }
6156 }
6157 
6158 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6159     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6160     if (!conn) return HCI_ROLE_INVALID;
6161     return (hci_role_t) conn->role;
6162 }
6163 
6164 
6165 #ifdef ENABLE_CLASSIC
6166 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6167     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6168     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6169     conn->request_role = role;
6170     hci_run();
6171     return ERROR_CODE_SUCCESS;
6172 }
6173 #endif
6174 
6175 #ifdef ENABLE_BLE
6176 
6177 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){
6178     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6179     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6180 
6181     conn->le_phy_update_all_phys    = all_phys;
6182     conn->le_phy_update_tx_phys     = tx_phys;
6183     conn->le_phy_update_rx_phys     = rx_phys;
6184     conn->le_phy_update_phy_options = phy_options;
6185 
6186     hci_run();
6187 
6188     return 0;
6189 }
6190 
6191 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6192     // check if already in list
6193     btstack_linked_list_iterator_t it;
6194     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6195     while (btstack_linked_list_iterator_has_next(&it)) {
6196         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6197         if (entry->address_type != address_type) {
6198             continue;
6199         }
6200         if (memcmp(entry->address, address, 6) != 0) {
6201             continue;
6202         }
6203 		// disallow if already scheduled to add
6204 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6205 			return ERROR_CODE_COMMAND_DISALLOWED;
6206 		}
6207 		// still on controller, but scheduled to remove -> re-add
6208 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6209 		return ERROR_CODE_SUCCESS;
6210     }
6211     // alloc and add to list
6212     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6213     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6214     entry->address_type = address_type;
6215     (void)memcpy(entry->address, address, 6);
6216     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6217     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6218     return ERROR_CODE_SUCCESS;
6219 }
6220 
6221 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6222     btstack_linked_list_iterator_t it;
6223     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6224     while (btstack_linked_list_iterator_has_next(&it)){
6225         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6226         if (entry->address_type != address_type) {
6227             continue;
6228         }
6229         if (memcmp(entry->address, address, 6) != 0) {
6230             continue;
6231         }
6232         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6233             // remove from controller if already present
6234             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6235         }  else {
6236             // directly remove entry from whitelist
6237             btstack_linked_list_iterator_remove(&it);
6238             btstack_memory_whitelist_entry_free(entry);
6239         }
6240         return ERROR_CODE_SUCCESS;
6241     }
6242     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6243 }
6244 
6245 static void hci_whitelist_clear(void){
6246     btstack_linked_list_iterator_t it;
6247     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6248     while (btstack_linked_list_iterator_has_next(&it)){
6249         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6250         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6251             // remove from controller if already present
6252             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6253             continue;
6254         }
6255         // directly remove entry from whitelist
6256         btstack_linked_list_iterator_remove(&it);
6257         btstack_memory_whitelist_entry_free(entry);
6258     }
6259 }
6260 
6261 // free all entries unconditionally
6262 static void hci_whitelist_free(void){
6263     btstack_linked_list_iterator_t lit;
6264     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
6265     while (btstack_linked_list_iterator_has_next(&lit)){
6266         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
6267         btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
6268         btstack_memory_whitelist_entry_free(entry);
6269     }
6270 }
6271 
6272 /**
6273  * @brief Clear Whitelist
6274  * @return 0 if ok
6275  */
6276 uint8_t gap_whitelist_clear(void){
6277     hci_whitelist_clear();
6278     hci_run();
6279     return ERROR_CODE_SUCCESS;
6280 }
6281 
6282 /**
6283  * @brief Add Device to Whitelist
6284  * @param address_typ
6285  * @param address
6286  * @return 0 if ok
6287  */
6288 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6289     uint8_t status = hci_whitelist_add(address_type, address);
6290     if (status){
6291         return status;
6292     }
6293     hci_run();
6294     return ERROR_CODE_SUCCESS;
6295 }
6296 
6297 /**
6298  * @brief Remove Device from Whitelist
6299  * @param address_typ
6300  * @param address
6301  * @return 0 if ok
6302  */
6303 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6304     uint8_t status = hci_whitelist_remove(address_type, address);
6305     if (status){
6306         return status;
6307     }
6308     hci_run();
6309     return ERROR_CODE_SUCCESS;
6310 }
6311 
6312 #ifdef ENABLE_LE_CENTRAL
6313 /**
6314  * @brief Connect with Whitelist
6315  * @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6316  * @return - if ok
6317  */
6318 uint8_t gap_connect_with_whitelist(void){
6319     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6320         return ERROR_CODE_COMMAND_DISALLOWED;
6321     }
6322     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6323     hci_run();
6324     return ERROR_CODE_SUCCESS;
6325 }
6326 
6327 /**
6328  * @brief Auto Connection Establishment - Start Connecting to device
6329  * @param address_typ
6330  * @param address
6331  * @return 0 if ok
6332  */
6333 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6334     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6335         return ERROR_CODE_COMMAND_DISALLOWED;
6336     }
6337 
6338     uint8_t status = hci_whitelist_add(address_type, address);
6339     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6340         return status;
6341     }
6342 
6343     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6344 
6345     hci_run();
6346     return ERROR_CODE_SUCCESS;
6347 }
6348 
6349 /**
6350  * @brief Auto Connection Establishment - Stop Connecting to device
6351  * @param address_typ
6352  * @param address
6353  * @return 0 if ok
6354  */
6355 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6356     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6357         return ERROR_CODE_COMMAND_DISALLOWED;
6358     }
6359 
6360     hci_whitelist_remove(address_type, address);
6361     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6362         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6363     }
6364     hci_run();
6365     return 0;
6366 }
6367 
6368 /**
6369  * @brief Auto Connection Establishment - Stop everything
6370  * @note  Convenience function to stop all active auto connection attempts
6371  */
6372 uint8_t gap_auto_connection_stop_all(void){
6373     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6374         return ERROR_CODE_COMMAND_DISALLOWED;
6375     }
6376     hci_whitelist_clear();
6377     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6378     hci_run();
6379     return ERROR_CODE_SUCCESS;
6380 }
6381 
6382 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6383     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6384     if (!conn) return 0;
6385     return conn->le_connection_interval;
6386 }
6387 #endif
6388 #endif
6389 
6390 #ifdef ENABLE_CLASSIC
6391 /**
6392  * @brief Set Extended Inquiry Response data
6393  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6394  * @note has to be done before stack starts up
6395  */
6396 void gap_set_extended_inquiry_response(const uint8_t * data){
6397     hci_stack->eir_data = data;
6398     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6399     hci_run();
6400 }
6401 
6402 /**
6403  * @brief Start GAP Classic Inquiry
6404  * @param duration in 1.28s units
6405  * @return 0 if ok
6406  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6407  */
6408 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6409     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6410     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6411     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6412         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6413     }
6414     hci_stack->inquiry_state = duration_in_1280ms_units;
6415     hci_run();
6416     return 0;
6417 }
6418 
6419 /**
6420  * @brief Stop GAP Classic Inquiry
6421  * @return 0 if ok
6422  */
6423 int gap_inquiry_stop(void){
6424     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6425         // emit inquiry complete event, before it even started
6426         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6427         hci_emit_event(event, sizeof(event), 1);
6428         return 0;
6429     }
6430     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6431     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6432     hci_run();
6433     return 0;
6434 }
6435 
6436 void gap_inquiry_set_lap(uint32_t lap){
6437     hci_stack->inquiry_lap = lap;
6438 }
6439 
6440 void gap_inquiry_set_scan_activity(uint16_t inquiry_scan_interval, uint16_t inquiry_scan_window){
6441     hci_stack->inquiry_scan_interval = inquiry_scan_interval;
6442     hci_stack->inquiry_scan_window   = inquiry_scan_window;
6443     hci_stack->gap_tasks |= GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
6444     hci_run();
6445 }
6446 
6447 
6448 /**
6449  * @brief Remote Name Request
6450  * @param addr
6451  * @param page_scan_repetition_mode
6452  * @param clock_offset only used when bit 15 is set
6453  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6454  */
6455 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6456     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6457     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6458     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6459     hci_stack->remote_name_clock_offset = clock_offset;
6460     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6461     hci_run();
6462     return 0;
6463 }
6464 
6465 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6466     hci_stack->gap_pairing_state = state;
6467     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6468     hci_run();
6469     return 0;
6470 }
6471 
6472 /**
6473  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6474  * @param addr
6475  * @param pin_data
6476  * @param pin_len
6477  * @return 0 if ok
6478  */
6479 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6480     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6481     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6482     hci_stack->gap_pairing_pin_len = pin_len;
6483     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6484 }
6485 
6486 /**
6487  * @brief Legacy Pairing Pin Code Response
6488  * @param addr
6489  * @param pin
6490  * @return 0 if ok
6491  */
6492 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6493     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6494 }
6495 
6496 /**
6497  * @brief Abort Legacy Pairing
6498  * @param addr
6499  * @param pin
6500  * @return 0 if ok
6501  */
6502 int gap_pin_code_negative(bd_addr_t addr){
6503     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6504     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6505 }
6506 
6507 /**
6508  * @brief SSP Passkey Response
6509  * @param addr
6510  * @param passkey
6511  * @return 0 if ok
6512  */
6513 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6514     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6515     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6516     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6517 }
6518 
6519 /**
6520  * @brief Abort SSP Passkey Entry/Pairing
6521  * @param addr
6522  * @param pin
6523  * @return 0 if ok
6524  */
6525 int gap_ssp_passkey_negative(const bd_addr_t addr){
6526     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6527     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6528 }
6529 
6530 /**
6531  * @brief Accept SSP Numeric Comparison
6532  * @param addr
6533  * @param passkey
6534  * @return 0 if ok
6535  */
6536 int gap_ssp_confirmation_response(const bd_addr_t addr){
6537     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6538     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6539 }
6540 
6541 /**
6542  * @brief Abort SSP Numeric Comparison/Pairing
6543  * @param addr
6544  * @param pin
6545  * @return 0 if ok
6546  */
6547 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6548     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6549     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6550 }
6551 
6552 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6553 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6554     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6555     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6556     connectionSetAuthenticationFlags(conn, flag);
6557     hci_run();
6558     return ERROR_CODE_SUCCESS;
6559 }
6560 #endif
6561 
6562 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6563 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6564     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6565 }
6566 
6567 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6568     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6569 }
6570 #endif
6571 
6572 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6573 /**
6574  * @brief Report Remote OOB Data
6575  * @param bd_addr
6576  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6577  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6578  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6579  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6580  */
6581 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){
6582     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6583     if (connection == NULL) {
6584         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6585     }
6586     connection->classic_oob_c_192 = c_192;
6587     connection->classic_oob_r_192 = r_192;
6588 
6589     // ignore P-256 if not supported by us
6590     if (hci_stack->secure_connections_active){
6591         connection->classic_oob_c_256 = c_256;
6592         connection->classic_oob_r_256 = r_256;
6593     }
6594 
6595     return ERROR_CODE_SUCCESS;
6596 }
6597 /**
6598  * @brief Generate new OOB data
6599  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6600  */
6601 void gap_ssp_generate_oob_data(void){
6602     hci_stack->classic_read_local_oob_data = true;
6603     hci_run();
6604 }
6605 
6606 #endif
6607 
6608 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6609 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6610     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6611     if (connection == NULL) {
6612         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6613     }
6614 
6615     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6616     connection->link_key_type = type;
6617 
6618     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6619 }
6620 
6621 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6622 /**
6623  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6624  * @param inquiry_mode see bluetooth_defines.h
6625  */
6626 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6627     hci_stack->inquiry_mode = inquiry_mode;
6628 }
6629 
6630 /**
6631  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6632  */
6633 void hci_set_sco_voice_setting(uint16_t voice_setting){
6634     hci_stack->sco_voice_setting = voice_setting;
6635 }
6636 
6637 /**
6638  * @brief Get SCO Voice Setting
6639  * @return current voice setting
6640  */
6641 uint16_t hci_get_sco_voice_setting(void){
6642     return hci_stack->sco_voice_setting;
6643 }
6644 
6645 static int hci_have_usb_transport(void){
6646     if (!hci_stack->hci_transport) return 0;
6647     const char * transport_name = hci_stack->hci_transport->name;
6648     if (!transport_name) return 0;
6649     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6650 }
6651 
6652 /** @brief Get SCO packet length for current SCO Voice setting
6653  *  @note  Using SCO packets of the exact length is required for USB transfer
6654  *  @return Length of SCO packets in bytes (not audio frames)
6655  */
6656 uint16_t hci_get_sco_packet_length(void){
6657     uint16_t sco_packet_length = 0;
6658 
6659 #ifdef ENABLE_SCO_OVER_HCI
6660     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6661     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6662 
6663     if (hci_have_usb_transport()){
6664         // see Core Spec for H2 USB Transfer.
6665         // 3 byte SCO header + 24 bytes per connection
6666         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6667         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6668     } else {
6669         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6670         sco_packet_length = 3 + 60 * multiplier;
6671         // assert that it still fits inside an SCO buffer
6672         if (sco_packet_length > hci_stack->sco_data_packet_length){
6673             sco_packet_length = 3 + 60;
6674         }
6675     }
6676 #endif
6677 
6678 #ifdef HAVE_SCO_TRANSPORT
6679     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6680     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6681     sco_packet_length = 3 + 60 * multiplier;
6682 #endif
6683     return sco_packet_length;
6684 }
6685 
6686 /**
6687 * @brief Sets the master/slave policy
6688 * @param policy (0: attempt to become master, 1: let connecting device decide)
6689 */
6690 void hci_set_master_slave_policy(uint8_t policy){
6691     hci_stack->master_slave_policy = policy;
6692 }
6693 
6694 #endif
6695 
6696 HCI_STATE hci_get_state(void){
6697     return hci_stack->state;
6698 }
6699 
6700 #ifdef ENABLE_CLASSIC
6701 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6702     hci_stack->gap_classic_accept_callback = accept_callback;
6703 }
6704 #endif
6705 
6706 /**
6707  * @brief Set callback for Bluetooth Hardware Error
6708  */
6709 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6710     hci_stack->hardware_error_callback = fn;
6711 }
6712 
6713 void hci_disconnect_all(void){
6714     btstack_linked_list_iterator_t it;
6715     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6716     while (btstack_linked_list_iterator_has_next(&it)){
6717         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6718         if (con->state == SENT_DISCONNECT) continue;
6719         con->state = SEND_DISCONNECT;
6720     }
6721     hci_run();
6722 }
6723 
6724 uint16_t hci_get_manufacturer(void){
6725     return hci_stack->manufacturer;
6726 }
6727 
6728 #ifdef ENABLE_BLE
6729 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6730     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6731     if (!hci_con) return NULL;
6732     return &hci_con->sm_connection;
6733 }
6734 
6735 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6736 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6737 #endif
6738 
6739 int gap_encryption_key_size(hci_con_handle_t con_handle){
6740     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6741     if (hci_connection == NULL) return 0;
6742     if (hci_is_le_connection(hci_connection)){
6743 #ifdef ENABLE_BLE
6744         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6745         if (sm_conn->sm_connection_encrypted) {
6746             return sm_conn->sm_actual_encryption_key_size;
6747         }
6748 #endif
6749     } else {
6750 #ifdef ENABLE_CLASSIC
6751         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6752             return hci_connection->encryption_key_size;
6753         }
6754 #endif
6755     }
6756     return 0;
6757 }
6758 
6759 int gap_authenticated(hci_con_handle_t con_handle){
6760     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6761     if (hci_connection == NULL) return 0;
6762 
6763     switch (hci_connection->address_type){
6764 #ifdef ENABLE_BLE
6765         case BD_ADDR_TYPE_LE_PUBLIC:
6766         case BD_ADDR_TYPE_LE_RANDOM:
6767             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6768             return hci_connection->sm_connection.sm_connection_authenticated;
6769 #endif
6770 #ifdef ENABLE_CLASSIC
6771         case BD_ADDR_TYPE_SCO:
6772         case BD_ADDR_TYPE_ACL:
6773             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6774 #endif
6775         default:
6776             return 0;
6777     }
6778 }
6779 
6780 int gap_secure_connection(hci_con_handle_t con_handle){
6781     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6782     if (hci_connection == NULL) return 0;
6783 
6784     switch (hci_connection->address_type){
6785 #ifdef ENABLE_BLE
6786         case BD_ADDR_TYPE_LE_PUBLIC:
6787         case BD_ADDR_TYPE_LE_RANDOM:
6788             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6789             return hci_connection->sm_connection.sm_connection_sc;
6790 #endif
6791 #ifdef ENABLE_CLASSIC
6792         case BD_ADDR_TYPE_SCO:
6793         case BD_ADDR_TYPE_ACL:
6794             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6795 #endif
6796         default:
6797             return 0;
6798     }
6799 }
6800 
6801 bool gap_bonded(hci_con_handle_t con_handle){
6802 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6803 	if (hci_connection == NULL) return 0;
6804 
6805 #ifdef ENABLE_CLASSIC
6806 	link_key_t link_key;
6807 	link_key_type_t link_key_type;
6808 #endif
6809 	switch (hci_connection->address_type){
6810 #ifdef ENABLE_BLE
6811 		case BD_ADDR_TYPE_LE_PUBLIC:
6812 		case BD_ADDR_TYPE_LE_RANDOM:
6813 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6814 #endif
6815 #ifdef ENABLE_CLASSIC
6816 		case BD_ADDR_TYPE_SCO:
6817 		case BD_ADDR_TYPE_ACL:
6818 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6819 #endif
6820 		default:
6821 			return false;
6822 	}
6823 }
6824 
6825 #ifdef ENABLE_BLE
6826 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6827     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6828     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6829     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6830     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6831     return sm_conn->sm_connection_authorization_state;
6832 }
6833 #endif
6834 
6835 #ifdef ENABLE_CLASSIC
6836 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){
6837     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6838     if (!conn) return GAP_CONNECTION_INVALID;
6839     conn->sniff_min_interval = sniff_min_interval;
6840     conn->sniff_max_interval = sniff_max_interval;
6841     conn->sniff_attempt = sniff_attempt;
6842     conn->sniff_timeout = sniff_timeout;
6843     hci_run();
6844     return 0;
6845 }
6846 
6847 /**
6848  * @brief Exit Sniff mode
6849  * @param con_handle
6850  @ @return 0 if ok
6851  */
6852 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6853     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6854     if (!conn) return GAP_CONNECTION_INVALID;
6855     conn->sniff_min_interval = 0xffff;
6856     hci_run();
6857     return 0;
6858 }
6859 
6860 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){
6861     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6862     if (!conn) return GAP_CONNECTION_INVALID;
6863     conn->sniff_subrating_max_latency = max_latency;
6864     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6865     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6866     hci_run();
6867     return ERROR_CODE_SUCCESS;
6868 }
6869 
6870 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){
6871     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6872     if (!conn) return GAP_CONNECTION_INVALID;
6873     conn->qos_service_type = service_type;
6874     conn->qos_token_rate = token_rate;
6875     conn->qos_peak_bandwidth = peak_bandwidth;
6876     conn->qos_latency = latency;
6877     conn->qos_delay_variation = delay_variation;
6878     hci_run();
6879     return ERROR_CODE_SUCCESS;
6880 }
6881 
6882 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6883     hci_stack->new_page_scan_interval = page_scan_interval;
6884     hci_stack->new_page_scan_window = page_scan_window;
6885     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6886     hci_run();
6887 }
6888 
6889 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6890     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6891     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6892     hci_run();
6893 }
6894 
6895 void gap_set_page_timeout(uint16_t page_timeout){
6896     hci_stack->page_timeout = page_timeout;
6897     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_TIMEOUT;
6898     hci_run();
6899 }
6900 
6901 #endif
6902 
6903 void hci_halting_defer(void){
6904     if (hci_stack->state != HCI_STATE_HALTING) return;
6905     switch (hci_stack->substate){
6906         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6907         case HCI_HALTING_CLOSE:
6908             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6909             break;
6910         default:
6911             break;
6912     }
6913 }
6914 
6915 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6916 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6917     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6918     if (le_device_db_index >= le_device_db_max_count()) return;
6919     uint8_t offset = le_device_db_index >> 3;
6920     uint8_t mask = 1 << (le_device_db_index & 7);
6921     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6922     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6923     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6924         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6925     }
6926 }
6927 
6928 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6929 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6930 	if (le_device_db_index >= le_device_db_max_count()) return;
6931 	uint8_t offset = le_device_db_index >> 3;
6932 	uint8_t mask = 1 << (le_device_db_index & 7);
6933 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6934 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6935 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6936 	}
6937 }
6938 
6939 uint8_t gap_load_resolving_list_from_le_device_db(void){
6940 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6941 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6942 	}
6943 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6944 		// restart le resolving list update
6945 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6946 	}
6947 	return ERROR_CODE_SUCCESS;
6948 }
6949 #endif
6950 
6951 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6952 void hci_setup_test_connections_fuzz(void){
6953     hci_connection_t * conn;
6954 
6955     // default address: 66:55:44:33:00:01
6956     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6957 
6958     // setup Controller info
6959     hci_stack->num_cmd_packets = 255;
6960     hci_stack->acl_packets_total_num = 255;
6961 
6962     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6963     addr[5] = 0x01;
6964     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6965     conn->con_handle = addr[5];
6966     conn->role  = HCI_ROLE_SLAVE;
6967     conn->state = RECEIVED_CONNECTION_REQUEST;
6968     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6969 
6970     // setup incoming Classic SCO connection with con handle 0x0002
6971     addr[5] = 0x02;
6972     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6973     conn->con_handle = addr[5];
6974     conn->role  = HCI_ROLE_SLAVE;
6975     conn->state = RECEIVED_CONNECTION_REQUEST;
6976     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6977 
6978     // setup ready Classic ACL connection with con handle 0x0003
6979     addr[5] = 0x03;
6980     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6981     conn->con_handle = addr[5];
6982     conn->role  = HCI_ROLE_SLAVE;
6983     conn->state = OPEN;
6984     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6985 
6986     // setup ready Classic SCO connection with con handle 0x0004
6987     addr[5] = 0x04;
6988     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6989     conn->con_handle = addr[5];
6990     conn->role  = HCI_ROLE_SLAVE;
6991     conn->state = OPEN;
6992     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6993 
6994     // setup ready LE ACL connection with con handle 0x005 and public address
6995     addr[5] = 0x05;
6996     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6997     conn->con_handle = addr[5];
6998     conn->role  = HCI_ROLE_SLAVE;
6999     conn->state = OPEN;
7000     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
7001     conn->sm_connection.sm_connection_encrypted = 1;
7002 }
7003 
7004 void hci_free_connections_fuzz(void){
7005     btstack_linked_list_iterator_t it;
7006     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
7007     while (btstack_linked_list_iterator_has_next(&it)){
7008         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
7009         btstack_linked_list_iterator_remove(&it);
7010         btstack_memory_hci_connection_free(con);
7011     }
7012 }
7013 void hci_simulate_working_fuzz(void){
7014     hci_init_done();
7015     hci_stack->num_cmd_packets = 255;
7016 }
7017 #endif
7018