xref: /btstack/src/hci.c (revision 3bb5ff27f3d47c809395c97731c4b72ac61d813e)
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     // CC2564C might emit Connection Complete for rejected incoming SCO connection
2046     // To prevent accidentally free'ing the CHI connection for the ACL connection,
2047     // check if the hci connection has been outgoing
2048     if (conn->state != SENT_CREATE_CONNECTION) return;
2049 
2050     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2051     bd_addr_t bd_address;
2052     (void)memcpy(&bd_address, conn->address, 6);
2053 
2054 #ifdef ENABLE_CLASSIC
2055     // cache needed data
2056     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2057 #endif
2058 
2059     // connection failed, remove entry
2060     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2061     btstack_memory_hci_connection_free( conn );
2062 
2063 #ifdef ENABLE_CLASSIC
2064     // notify client if dedicated bonding
2065     if (notify_dedicated_bonding_failed){
2066         log_info("hci notify_dedicated_bonding_failed");
2067         hci_emit_dedicated_bonding_result(bd_address, status);
2068     }
2069 
2070     // if authentication error, also delete link key
2071     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2072         gap_drop_link_key_for_bd_addr(bd_address);
2073     }
2074 #else
2075     UNUSED(status);
2076 #endif
2077 }
2078 
2079 #ifdef ENABLE_CLASSIC
2080 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2081     // SSP Controller
2082     if (features[6] & (1 << 3)){
2083         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2084     }
2085     // eSCO
2086     if (features[3] & (1<<7)){
2087         conn->remote_supported_features[0] |= 1;
2088     }
2089     // Extended features
2090     if (features[7] & (1<<7)){
2091         conn->remote_supported_features[0] |= 2;
2092     }
2093 }
2094 
2095 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2096     // SSP Host
2097     if (features[0] & (1 << 0)){
2098         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2099     }
2100     // SC Host
2101     if (features[0] & (1 << 3)){
2102         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2103     }
2104 }
2105 
2106 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2107     // SC Controller
2108     if (features[1] & (1 << 0)){
2109         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2110     }
2111 }
2112 
2113 static void hci_handle_remote_features_received(hci_connection_t * conn){
2114     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2115     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2116     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2117     if (conn->bonding_flags & BONDING_DEDICATED){
2118         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2119     }
2120 }
2121 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2122     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2123     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2124 }
2125 
2126 #endif
2127 
2128 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2129     // handle BT initialization
2130     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2131         hci_initializing_event_handler(packet, size);
2132     }
2133 
2134     // help with BT sleep
2135     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2136         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2137         && (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable))) {
2138         hci_initializing_next_state();
2139     }
2140 }
2141 
2142 #ifdef ENABLE_CLASSIC
2143 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2144     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2145     conn->encryption_key_size = encryption_key_size;
2146 
2147     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2148         conn->requested_security_level = LEVEL_0;
2149         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2150         return;
2151     }
2152 
2153     // Request remote features if not already done
2154     hci_trigger_remote_features_for_connection(conn);
2155 
2156     // Request Authentication if not already done
2157     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2158     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2159 }
2160 #endif
2161 
2162 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2163     UNUSED(size);
2164 
2165     uint16_t manufacturer;
2166 #ifdef ENABLE_CLASSIC
2167     hci_con_handle_t handle;
2168     hci_connection_t * conn;
2169     uint8_t status;
2170 #endif
2171     // get num cmd packets - limit to 1 to reduce complexity
2172     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2173 
2174     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2175     switch (opcode){
2176         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2177             if (packet[5]) break;
2178             // terminate, name 248 chars
2179             packet[6+248] = 0;
2180             log_info("local name: %s", &packet[6]);
2181             break;
2182         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2183             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2184             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2185                 uint16_t acl_len = little_endian_read_16(packet, 6);
2186                 uint16_t sco_len = packet[8];
2187 
2188                 // determine usable ACL/SCO payload size
2189                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2190                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2191 
2192                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2193                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2194 
2195                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2196                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2197                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2198             }
2199             break;
2200         case HCI_OPCODE_HCI_READ_RSSI:
2201             if (packet[5] == ERROR_CODE_SUCCESS){
2202                 uint8_t event[5];
2203                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2204                 event[1] = 3;
2205                 (void)memcpy(&event[2], &packet[6], 3);
2206                 hci_emit_event(event, sizeof(event), 1);
2207             }
2208             break;
2209 #ifdef ENABLE_BLE
2210         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2211             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2212             hci_stack->le_acl_packets_total_num = packet[8];
2213             // determine usable ACL payload size
2214             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2215                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2216             }
2217             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2218             break;
2219 #endif
2220 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2221         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2222             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2223             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2224             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);
2225             break;
2226 #endif
2227 #ifdef ENABLE_LE_CENTRAL
2228         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2229             hci_stack->le_whitelist_capacity = packet[6];
2230             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2231             break;
2232 #endif
2233         case HCI_OPCODE_HCI_READ_BD_ADDR:
2234             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2235             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));
2236 #ifdef ENABLE_CLASSIC
2237             if (hci_stack->link_key_db){
2238                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2239             }
2240 #endif
2241             break;
2242 #ifdef ENABLE_CLASSIC
2243         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2244             hci_emit_discoverable_enabled(hci_stack->discoverable);
2245             break;
2246         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2247             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2248                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2249                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2250                 hci_emit_event(event, sizeof(event), 1);
2251             }
2252             break;
2253 #endif
2254         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2255             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2256 
2257 #ifdef ENABLE_CLASSIC
2258             // determine usable ACL packet types based on host buffer size and supported features
2259             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2260             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2261 #endif
2262             // Classic/LE
2263             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2264             break;
2265         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2266             manufacturer = little_endian_read_16(packet, 10);
2267             // map Cypress to Broadcom
2268             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2269                 log_info("Treat Cypress as Broadcom");
2270                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2271                 little_endian_store_16(packet, 10, manufacturer);
2272             }
2273             hci_stack->manufacturer = manufacturer;
2274             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2275             break;
2276         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2277             hci_stack->local_supported_commands[0] =
2278                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2279                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2280                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2281                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2282                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2283                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2284                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2285                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2286             hci_stack->local_supported_commands[1] =
2287                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2288                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2289                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2290                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2291                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2292             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2293             break;
2294 #ifdef ENABLE_CLASSIC
2295         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2296             if (packet[5]) return;
2297             hci_stack->synchronous_flow_control_enabled = 1;
2298             break;
2299         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2300             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2301             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2302             conn   = hci_connection_for_handle(handle);
2303             if (conn != NULL) {
2304                 uint8_t key_size = 0;
2305                 if (status == 0){
2306                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2307                     log_info("Handle %04x key Size: %u", handle, key_size);
2308                 } else {
2309                     key_size = 1;
2310                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2311                 }
2312                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2313             }
2314             break;
2315         // assert pairing complete event is emitted.
2316         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2317         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2318         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2319         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2320             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2321             // lookup connection by gap pairing addr
2322             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2323             if (conn == NULL) break;
2324             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2325             break;
2326 
2327 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2328         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2329         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2330             uint8_t event[67];
2331             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2332             event[1] = 65;
2333             (void)memset(&event[2], 0, 65);
2334             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2335                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2336                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2337                     event[2] = 3;
2338                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2339                 } else {
2340                     event[2] = 1;
2341                 }
2342             }
2343             hci_emit_event(event, sizeof(event), 0);
2344             break;
2345         }
2346 
2347         // note: only needed if user does not provide OOB data
2348         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2349             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2350             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2351             if (conn == NULL) break;
2352             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2353             break;
2354 #endif
2355 #endif
2356         default:
2357             break;
2358     }
2359 }
2360 
2361 #ifdef ENABLE_BLE
2362 static void event_handle_le_connection_complete(const uint8_t * packet){
2363 	bd_addr_t addr;
2364 	bd_addr_type_t addr_type;
2365 	hci_connection_t * conn;
2366 
2367 	// Connection management
2368 	reverse_bd_addr(&packet[8], addr);
2369 	addr_type = (bd_addr_type_t)packet[7];
2370 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2371 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2372 
2373 #ifdef ENABLE_LE_CENTRAL
2374 	// handle error: error is reported only to the initiator -> outgoing connection
2375 	if (packet[3]){
2376 
2377 		// handle cancelled outgoing connection
2378 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2379 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2380 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2381 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2382 		    // reset state
2383             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2384             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2385 			// get outgoing connection conn struct for direct connect
2386 			conn = gap_get_outgoing_connection();
2387 		}
2388 
2389 		// outgoing le connection establishment is done
2390 		if (conn){
2391 			// remove entry
2392 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2393 			btstack_memory_hci_connection_free( conn );
2394 		}
2395 		return;
2396 	}
2397 #endif
2398 
2399 	// on success, both hosts receive connection complete event
2400 	if (packet[6] == HCI_ROLE_MASTER){
2401 #ifdef ENABLE_LE_CENTRAL
2402 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2403 		// note: no hci_connection_t object exists yet for connect with whitelist
2404 		if (hci_is_le_connection_type(addr_type)){
2405 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2406 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2407 		}
2408 #endif
2409 	} else {
2410 #ifdef ENABLE_LE_PERIPHERAL
2411 		// if we're slave, it was an incoming connection, advertisements have stopped
2412 		hci_stack->le_advertisements_active = false;
2413 #endif
2414 	}
2415 
2416 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2417 	if (!conn){
2418 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2419 	}
2420 
2421 	// no memory, sorry.
2422 	if (!conn){
2423 		return;
2424 	}
2425 
2426 	conn->state = OPEN;
2427 	conn->role  = packet[6];
2428 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2429 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2430 
2431 #ifdef ENABLE_LE_PERIPHERAL
2432 	if (packet[6] == HCI_ROLE_SLAVE){
2433 		hci_update_advertisements_enabled_for_current_roles();
2434 	}
2435 #endif
2436 
2437     // init unenhanced att bearer mtu
2438     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2439     conn->att_connection.mtu_exchanged = false;
2440 
2441     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2442 
2443 	// restart timer
2444 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2445 	// btstack_run_loop_add_timer(&conn->timeout);
2446 
2447 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2448 
2449 	hci_emit_nr_connections_changed();
2450 }
2451 #endif
2452 
2453 #ifdef ENABLE_CLASSIC
2454 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){
2455     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2456     // LEVEL_4 is tested by l2cap
2457     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2458     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2459     if (level >= LEVEL_3){
2460         // MITM not possible without keyboard or display
2461         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2462         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2463 
2464         // MITM possible if one side has keyboard and the other has keyboard or display
2465         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2466         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2467 
2468         // MITM not possible if one side has only display and other side has no keyboard
2469         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2470         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2471     }
2472     // LEVEL 2 requires SSP, which is a given
2473     return true;
2474 }
2475 
2476 static bool btstack_is_null(uint8_t * data, uint16_t size){
2477     uint16_t i;
2478     for (i=0; i < size ; i++){
2479         if (data[i] != 0) {
2480             return false;
2481         }
2482     }
2483     return true;
2484 }
2485 
2486 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2487     // get requested security level
2488     gap_security_level_t requested_security_level = conn->requested_security_level;
2489     if (hci_stack->gap_secure_connections_only_mode){
2490         requested_security_level = LEVEL_4;
2491     }
2492 
2493     // assess security: LEVEL 4 requires SC
2494     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2495     if ((requested_security_level == LEVEL_4) &&
2496         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2497         !hci_remote_sc_enabled(conn)){
2498         log_info("Level 4 required, but SC not supported -> abort");
2499         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2500         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2501         return;
2502     }
2503 
2504     // assess security based on io capabilities
2505     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2506         // responder: fully validate io caps of both sides as well as OOB data
2507         bool security_possible = false;
2508         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2509 
2510 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2511         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2512         // so we merge the OOB data availability
2513         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2514         if (conn->classic_oob_c_192 != NULL){
2515             have_oob_data |= 1;
2516         }
2517         if (conn->classic_oob_c_256 != NULL){
2518             have_oob_data |= 2;
2519         }
2520         // for up to Level 3, either P-192 as well as P-256 will do
2521         // 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
2522         // if remote does not SC, we should not receive P-256 data either
2523         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2524             security_possible = true;
2525         }
2526         // for Level 4, P-256 is needed
2527         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2528             security_possible = true;
2529         }
2530 #endif
2531 
2532         if (security_possible == false){
2533             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2534             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2535             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2536             return;
2537         }
2538     } else {
2539         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2540 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2541 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2542         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2543             log_info("Level 3+ required, but no input/output -> abort");
2544             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2545             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2546             return;
2547         }
2548 #endif
2549 #endif
2550     }
2551 
2552 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2553     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2554         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2555     } else {
2556         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2557     }
2558 #endif
2559 }
2560 
2561 #endif
2562 
2563 static void event_handler(uint8_t *packet, uint16_t size){
2564 
2565     uint16_t event_length = packet[1];
2566 
2567     // assert packet is complete
2568     if (size != (event_length + 2u)){
2569         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2570         return;
2571     }
2572 
2573     bd_addr_type_t addr_type;
2574     hci_con_handle_t handle;
2575     hci_connection_t * conn;
2576     int i;
2577     int create_connection_cmd;
2578 
2579 #ifdef ENABLE_CLASSIC
2580     hci_link_type_t link_type;
2581     bd_addr_t addr;
2582 #endif
2583 
2584     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2585 
2586     switch (hci_event_packet_get_type(packet)) {
2587 
2588         case HCI_EVENT_COMMAND_COMPLETE:
2589             handle_command_complete_event(packet, size);
2590             break;
2591 
2592         case HCI_EVENT_COMMAND_STATUS:
2593             // get num cmd packets - limit to 1 to reduce complexity
2594             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2595 
2596             // check command status to detected failed outgoing connections
2597             create_connection_cmd = 0;
2598 #ifdef ENABLE_CLASSIC
2599             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2600                 create_connection_cmd = 1;
2601             }
2602 #endif
2603 #ifdef ENABLE_LE_CENTRAL
2604             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2605                 create_connection_cmd = 1;
2606             }
2607 #endif
2608             if (create_connection_cmd) {
2609                 uint8_t status = hci_event_command_status_get_status(packet);
2610                 addr_type = hci_stack->outgoing_addr_type;
2611                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2612                 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);
2613 
2614                 // reset outgoing address info
2615                 memset(hci_stack->outgoing_addr, 0, 6);
2616                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2617 
2618                 // on error
2619                 if (status != ERROR_CODE_SUCCESS){
2620 #ifdef ENABLE_LE_CENTRAL
2621                     if (hci_is_le_connection_type(addr_type)){
2622                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2623                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2624                     }
2625 #endif
2626                     // error => outgoing connection failed
2627                     if (conn != NULL){
2628                         hci_handle_connection_failed(conn, status);
2629                     }
2630                 }
2631             }
2632 
2633 #ifdef ENABLE_CLASSIC
2634             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2635                 uint8_t status = hci_event_command_status_get_status(packet);
2636                 log_info("command status (inquiry), status %x", status);
2637                 if (status == ERROR_CODE_SUCCESS) {
2638                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2639                 } else {
2640                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2641                 }
2642             }
2643 #endif
2644             break;
2645 
2646         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2647             if (size < 3) return;
2648             uint16_t num_handles = packet[2];
2649             if (size != (3u + num_handles * 4u)) return;
2650             uint16_t offset = 3;
2651             for (i=0; i<num_handles;i++){
2652                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2653                 offset += 2u;
2654                 uint16_t num_packets = little_endian_read_16(packet, offset);
2655                 offset += 2u;
2656 
2657                 conn = hci_connection_for_handle(handle);
2658                 if (!conn){
2659                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2660                     continue;
2661                 }
2662 
2663                 if (conn->num_packets_sent >= num_packets){
2664                     conn->num_packets_sent -= num_packets;
2665                 } else {
2666                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2667                     conn->num_packets_sent = 0;
2668                 }
2669                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2670 
2671 #ifdef ENABLE_CLASSIC
2672                 // For SCO, we do the can_send_now_check here
2673                 hci_notify_if_sco_can_send_now();
2674 #endif
2675             }
2676             break;
2677         }
2678 
2679 #ifdef ENABLE_CLASSIC
2680         case HCI_EVENT_INQUIRY_COMPLETE:
2681             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2682                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2683                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2684                 hci_emit_event(event, sizeof(event), 1);
2685             }
2686             break;
2687         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2688             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2689                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2690             }
2691             break;
2692         case HCI_EVENT_CONNECTION_REQUEST:
2693             reverse_bd_addr(&packet[2], addr);
2694             link_type = (hci_link_type_t) packet[11];
2695 
2696             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2697             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2698                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2699                 bd_addr_copy(hci_stack->decline_addr, addr);
2700                 break;
2701             }
2702 
2703             if (hci_stack->gap_classic_accept_callback != NULL){
2704                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2705                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2706                     bd_addr_copy(hci_stack->decline_addr, addr);
2707                     break;
2708                 }
2709             }
2710 
2711             // TODO: eval COD 8-10
2712             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2713             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2714             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2715             if (!conn) {
2716                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2717             }
2718             if (!conn) {
2719                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2720                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2721                 bd_addr_copy(hci_stack->decline_addr, addr);
2722                 hci_run();
2723                 // avoid event to higher layer
2724                 return;
2725             }
2726             conn->role  = HCI_ROLE_SLAVE;
2727             conn->state = RECEIVED_CONNECTION_REQUEST;
2728             // store info about eSCO
2729             if (link_type == HCI_LINK_TYPE_ESCO){
2730                 conn->remote_supported_features[0] |= 1;
2731             }
2732             hci_run();
2733             break;
2734 
2735         case HCI_EVENT_CONNECTION_COMPLETE:
2736             // Connection management
2737             reverse_bd_addr(&packet[5], addr);
2738             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2739             addr_type = BD_ADDR_TYPE_ACL;
2740             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2741             if (conn) {
2742                 if (!packet[2]){
2743                     conn->state = OPEN;
2744                     conn->con_handle = little_endian_read_16(packet, 3);
2745 
2746                     // queue set supervision timeout if we're master
2747                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2748                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2749                     }
2750 
2751                     // restart timer
2752                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2753                     btstack_run_loop_add_timer(&conn->timeout);
2754 
2755                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2756 
2757                     hci_emit_nr_connections_changed();
2758                 } else {
2759                     // connection failed
2760                     hci_handle_connection_failed(conn, packet[2]);
2761                 }
2762             }
2763             break;
2764 
2765         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2766             reverse_bd_addr(&packet[5], addr);
2767             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2768             if (packet[2]){
2769                 // connection failed
2770                 break;
2771             }
2772             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2773             if (!conn) {
2774                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2775             }
2776             if (!conn) {
2777                 break;
2778             }
2779             conn->state = OPEN;
2780             conn->con_handle = little_endian_read_16(packet, 3);
2781 
2782 #ifdef ENABLE_SCO_OVER_HCI
2783             // update SCO
2784             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2785                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2786             }
2787             // trigger can send now
2788             if (hci_have_usb_transport()){
2789                 hci_stack->sco_can_send_now = true;
2790             }
2791 #endif
2792 #ifdef HAVE_SCO_TRANSPORT
2793             // configure sco transport
2794             if (hci_stack->sco_transport != NULL){
2795                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2796                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2797             }
2798 #endif
2799             break;
2800 
2801         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2802             handle = little_endian_read_16(packet, 3);
2803             conn = hci_connection_for_handle(handle);
2804             if (!conn) break;
2805             if (!packet[2]){
2806                 const uint8_t * features = &packet[5];
2807                 hci_handle_remote_features_page_0(conn, features);
2808 
2809                 // read extended features if possible
2810                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2811                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2812                     break;
2813                 }
2814             }
2815             hci_handle_remote_features_received(conn);
2816             break;
2817 
2818         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2819             handle = little_endian_read_16(packet, 3);
2820             conn = hci_connection_for_handle(handle);
2821             if (!conn) break;
2822             // status = ok, page = 1
2823             if (!packet[2]) {
2824                 uint8_t page_number = packet[5];
2825                 uint8_t maximum_page_number = packet[6];
2826                 const uint8_t * features = &packet[7];
2827                 bool done = false;
2828                 switch (page_number){
2829                     case 1:
2830                         hci_handle_remote_features_page_1(conn, features);
2831                         if (maximum_page_number >= 2){
2832                             // get Secure Connections (Controller) from Page 2 if available
2833                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2834                         } else {
2835                             // otherwise, assume SC (Controller) == SC (Host)
2836                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2837                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2838                             }
2839                             done = true;
2840                         }
2841                         break;
2842                     case 2:
2843                         hci_handle_remote_features_page_2(conn, features);
2844                         done = true;
2845                         break;
2846                     default:
2847                         break;
2848                 }
2849                 if (!done) break;
2850             }
2851             hci_handle_remote_features_received(conn);
2852             break;
2853 
2854         case HCI_EVENT_LINK_KEY_REQUEST:
2855 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2856             hci_event_link_key_request_get_bd_addr(packet, addr);
2857             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2858             if (!conn) break;
2859 
2860             // lookup link key in db if not cached
2861             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2862                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2863             }
2864 
2865             // response sent by hci_run()
2866             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2867 #endif
2868             break;
2869 
2870         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2871             hci_event_link_key_request_get_bd_addr(packet, addr);
2872             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2873             if (!conn) break;
2874 
2875             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2876 
2877             // CVE-2020-26555: ignore NULL link key
2878             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2879             if (btstack_is_null(&packet[8], 16)) break;
2880 
2881             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2882             // Change Connection Encryption keeps link key type
2883             if (link_key_type != CHANGED_COMBINATION_KEY){
2884                 conn->link_key_type = link_key_type;
2885             }
2886 
2887             // cache link key. link keys stored in little-endian format for legacy reasons
2888             memcpy(&conn->link_key, &packet[8], 16);
2889 
2890             // only store link key:
2891             // - if bondable enabled
2892             if (hci_stack->bondable == false) break;
2893             // - if security level sufficient
2894             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2895             // - for SSP, also check if remote side requested bonding as well
2896             if (conn->link_key_type != COMBINATION_KEY){
2897                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2898                 if (!remote_bonding){
2899                     break;
2900                 }
2901             }
2902             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2903             break;
2904         }
2905 
2906         case HCI_EVENT_PIN_CODE_REQUEST:
2907             hci_event_pin_code_request_get_bd_addr(packet, addr);
2908             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2909             if (!conn) break;
2910 
2911             hci_pairing_started(conn, false);
2912             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2913             if (!hci_stack->bondable ){
2914                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2915                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2916                 hci_run();
2917                 return;
2918             }
2919             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2920             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2921                 log_info("Level 4 required, but SC not supported -> abort");
2922                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2923                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2924                 hci_run();
2925                 return;
2926             }
2927             break;
2928 
2929         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2930             hci_event_io_capability_response_get_bd_addr(packet, addr);
2931             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2932             if (!conn) break;
2933 
2934             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2935             hci_pairing_started(conn, true);
2936             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2937             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2938 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2939             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2940 #endif
2941             break;
2942 
2943         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2944             hci_event_io_capability_response_get_bd_addr(packet, addr);
2945             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2946             if (!conn) break;
2947 
2948             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2949             hci_connection_timestamp(conn);
2950             hci_pairing_started(conn, true);
2951             break;
2952 
2953 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2954         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2955             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2956             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2957             if (!conn) break;
2958 
2959             hci_connection_timestamp(conn);
2960 
2961             hci_pairing_started(conn, true);
2962 
2963             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2964             break;
2965 #endif
2966 
2967         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2968             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2969             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2970             if (!conn) break;
2971             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2972                 if (hci_stack->ssp_auto_accept){
2973                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2974                 };
2975             } else {
2976                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2977                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2978                 // don't forward event to app
2979                 hci_run();
2980                 return;
2981             }
2982             break;
2983 
2984         case HCI_EVENT_USER_PASSKEY_REQUEST:
2985             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2986             if (hci_stack->ssp_auto_accept){
2987                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2988             };
2989             break;
2990 
2991         case HCI_EVENT_MODE_CHANGE:
2992             handle = hci_event_mode_change_get_handle(packet);
2993             conn = hci_connection_for_handle(handle);
2994             if (!conn) break;
2995             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2996             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2997             break;
2998 #endif
2999 
3000         case HCI_EVENT_ENCRYPTION_CHANGE:
3001             handle = hci_event_encryption_change_get_connection_handle(packet);
3002             conn = hci_connection_for_handle(handle);
3003             if (!conn) break;
3004             if (hci_event_encryption_change_get_status(packet) == 0u) {
3005                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3006                 if (encryption_enabled){
3007                     if (hci_is_le_connection(conn)){
3008                         // For LE, we accept connection as encrypted
3009                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3010                     }
3011 #ifdef ENABLE_CLASSIC
3012                     else {
3013 
3014                         // dedicated bonding: send result and disconnect
3015                         if (conn->bonding_flags & BONDING_DEDICATED){
3016                             conn->bonding_flags &= ~BONDING_DEDICATED;
3017                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3018                             conn->bonding_status = packet[2];
3019                             break;
3020                         }
3021 
3022                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3023                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3024                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3025                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3026                             log_info("SC during pairing, but only E0 now -> abort");
3027                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3028                             break;
3029                         }
3030 
3031                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3032                         if (connected_uses_aes_ccm){
3033                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3034                         }
3035 
3036 #ifdef ENABLE_TESTING_SUPPORT
3037                         // work around for issue with PTS dongle
3038                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3039 #endif
3040 
3041                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3042                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3043                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3044                         } else {
3045                             // if not, pretend everything is perfect
3046                             hci_handle_read_encryption_key_size_complete(conn, 16);
3047                         }
3048                     }
3049 #endif
3050                 } else {
3051                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3052                 }
3053             }
3054 
3055             break;
3056 
3057 #ifdef ENABLE_CLASSIC
3058         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3059             handle = hci_event_authentication_complete_get_connection_handle(packet);
3060             conn = hci_connection_for_handle(handle);
3061             if (!conn) break;
3062 
3063             // clear authentication active flag
3064             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3065             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3066 
3067             // authenticated only if auth status == 0
3068             if (hci_event_authentication_complete_get_status(packet) == 0){
3069                 // authenticated
3070                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3071 
3072                 // If not already encrypted, start encryption
3073                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3074                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3075                     break;
3076                 }
3077             }
3078 
3079             // emit updated security level
3080             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3081             break;
3082 
3083         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3084             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3085             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3086             if (!conn) break;
3087 
3088             // treat successfully paired connection as authenticated
3089             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3090                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3091             }
3092 
3093             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3094             break;
3095 #endif
3096 
3097         // HCI_EVENT_DISCONNECTION_COMPLETE
3098         // has been split, to first notify stack before shutting connection down
3099         // see end of function, too.
3100         case HCI_EVENT_DISCONNECTION_COMPLETE:
3101             if (packet[2]) break;   // status != 0
3102             handle = little_endian_read_16(packet, 3);
3103             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3104             if (hci_stack->acl_fragmentation_total_size > 0u) {
3105                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3106                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3107                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3108                     hci_stack->acl_fragmentation_total_size = 0;
3109                     hci_stack->acl_fragmentation_pos = 0;
3110                     if (release_buffer){
3111                         hci_release_packet_buffer();
3112                     }
3113                 }
3114             }
3115 
3116             conn = hci_connection_for_handle(handle);
3117             if (!conn) break;
3118 #ifdef ENABLE_CLASSIC
3119             // pairing failed if it was ongoing
3120             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3121 #endif
3122 
3123             // emit dedicatd bonding event
3124             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3125                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3126             }
3127 
3128             // mark connection for shutdown, stop timers, reset state
3129             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3130             hci_connection_stop_timer(conn);
3131             hci_connection_init(conn);
3132 
3133 #ifdef ENABLE_BLE
3134 #ifdef ENABLE_LE_PERIPHERAL
3135             // re-enable advertisements for le connections if active
3136             if (hci_is_le_connection(conn)){
3137                 hci_update_advertisements_enabled_for_current_roles();
3138             }
3139 #endif
3140 #endif
3141             break;
3142 
3143         case HCI_EVENT_HARDWARE_ERROR:
3144             log_error("Hardware Error: 0x%02x", packet[2]);
3145             if (hci_stack->hardware_error_callback){
3146                 (*hci_stack->hardware_error_callback)(packet[2]);
3147             } else {
3148                 // if no special requests, just reboot stack
3149                 hci_power_control_off();
3150                 hci_power_control_on();
3151             }
3152             break;
3153 
3154 #ifdef ENABLE_CLASSIC
3155         case HCI_EVENT_ROLE_CHANGE:
3156             if (packet[2]) break;   // status != 0
3157             reverse_bd_addr(&packet[3], addr);
3158             addr_type = BD_ADDR_TYPE_ACL;
3159             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3160             if (!conn) break;
3161             conn->role = packet[9];
3162             break;
3163 #endif
3164 
3165         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3166             // release packet buffer only for asynchronous transport and if there are not further fragements
3167             if (hci_transport_synchronous()) {
3168                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3169                 return; // instead of break: to avoid re-entering hci_run()
3170             }
3171             hci_stack->acl_fragmentation_tx_active = 0;
3172             if (hci_stack->acl_fragmentation_total_size) break;
3173             hci_release_packet_buffer();
3174 
3175             // L2CAP receives this event via the hci_emit_event below
3176 
3177 #ifdef ENABLE_CLASSIC
3178             // For SCO, we do the can_send_now_check here
3179             hci_notify_if_sco_can_send_now();
3180 #endif
3181             break;
3182 
3183 #ifdef ENABLE_CLASSIC
3184         case HCI_EVENT_SCO_CAN_SEND_NOW:
3185             // For SCO, we do the can_send_now_check here
3186             hci_stack->sco_can_send_now = true;
3187             hci_notify_if_sco_can_send_now();
3188             return;
3189 
3190         // explode inquriy results for easier consumption
3191         case HCI_EVENT_INQUIRY_RESULT:
3192         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3193         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3194             gap_inquiry_explode(packet, size);
3195             break;
3196 #endif
3197 
3198 #ifdef ENABLE_BLE
3199         case HCI_EVENT_LE_META:
3200             switch (packet[2]){
3201 #ifdef ENABLE_LE_CENTRAL
3202                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3203                     // log_info("advertising report received");
3204                     if (!hci_stack->le_scanning_enabled) break;
3205                     le_handle_advertisement_report(packet, size);
3206                     break;
3207 #endif
3208                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3209 					event_handle_le_connection_complete(packet);
3210                     break;
3211 
3212                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3213                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3214                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3215                     conn = hci_connection_for_handle(handle);
3216                     if (!conn) break;
3217                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3218                     break;
3219 
3220                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3221                     // connection
3222                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3223                     conn = hci_connection_for_handle(handle);
3224                     if (conn) {
3225                         // read arguments
3226                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3227                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3228                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3229                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3230 
3231                         // validate against current connection parameter range
3232                         le_connection_parameter_range_t existing_range;
3233                         gap_get_connection_parameter_range(&existing_range);
3234                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3235                         if (update_parameter){
3236                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3237                             conn->le_conn_interval_min = le_conn_interval_min;
3238                             conn->le_conn_interval_max = le_conn_interval_max;
3239                             conn->le_conn_latency = le_conn_latency;
3240                             conn->le_supervision_timeout = le_supervision_timeout;
3241                         } else {
3242                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3243                         }
3244                     }
3245                     break;
3246 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3247                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3248                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3249                     conn = hci_connection_for_handle(handle);
3250                     if (conn) {
3251                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3252                     }
3253                     break;
3254 #endif
3255                 default:
3256                     break;
3257             }
3258             break;
3259 #endif
3260         case HCI_EVENT_VENDOR_SPECIFIC:
3261             // Vendor specific commands often create vendor specific event instead of num completed packets
3262             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3263             switch (hci_stack->manufacturer){
3264                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3265                     hci_stack->num_cmd_packets = 1;
3266                     break;
3267                 default:
3268                     break;
3269             }
3270             break;
3271         default:
3272             break;
3273     }
3274 
3275     handle_event_for_current_stack_state(packet, size);
3276 
3277     // notify upper stack
3278 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3279 
3280     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3281     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3282 		handle = little_endian_read_16(packet, 3);
3283 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3284 		// discard connection if app did not trigger a reconnect in the event handler
3285 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3286 			hci_shutdown_connection(aConn);
3287 		}
3288     }
3289 
3290 	// execute main loop
3291 	hci_run();
3292 }
3293 
3294 #ifdef ENABLE_CLASSIC
3295 
3296 #ifdef ENABLE_SCO_OVER_HCI
3297 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3298 static void sco_schedule_tx(hci_connection_t * conn);
3299 
3300 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3301     log_debug("SCO TX Timeout");
3302     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3303     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3304     if (!conn) return;
3305 
3306     // trigger send
3307     conn->sco_tx_ready = 1;
3308     // extra packet if CVSD but SCO buffer is too short
3309     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3310         conn->sco_tx_ready++;
3311     }
3312     hci_notify_if_sco_can_send_now();
3313 }
3314 
3315 
3316 #define SCO_TX_AFTER_RX_MS (6)
3317 
3318 static void sco_schedule_tx(hci_connection_t * conn){
3319 
3320     uint32_t now = btstack_run_loop_get_time_ms();
3321     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3322     int time_delta_ms = sco_tx_ms - now;
3323 
3324     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3325 
3326     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3327     btstack_run_loop_remove_timer(timer);
3328     btstack_run_loop_set_timer(timer, time_delta_ms);
3329     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3330     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3331     btstack_run_loop_add_timer(timer);
3332 }
3333 #endif
3334 
3335 static void sco_handler(uint8_t * packet, uint16_t size){
3336     // lookup connection struct
3337     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3338     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3339     if (!conn) return;
3340 
3341 #ifdef ENABLE_SCO_OVER_HCI
3342     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3343     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3344         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3345             packet[2] = 0x3c;
3346             memmove(&packet[3], &packet[23], 63);
3347             size = 63;
3348         }
3349     }
3350 
3351     if (hci_have_usb_transport()){
3352         // Nothing to do
3353     } else {
3354         // 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);
3355         if (hci_stack->synchronous_flow_control_enabled == 0){
3356             uint32_t now = btstack_run_loop_get_time_ms();
3357 
3358             if (!conn->sco_rx_valid){
3359                 // ignore first 10 packets
3360                 conn->sco_rx_count++;
3361                 // log_debug("sco rx count %u", conn->sco_rx_count);
3362                 if (conn->sco_rx_count == 10) {
3363                     // use first timestamp as is and pretent it just started
3364                     conn->sco_rx_ms = now;
3365                     conn->sco_rx_valid = 1;
3366                     conn->sco_rx_count = 0;
3367                     sco_schedule_tx(conn);
3368                 }
3369             } else {
3370                 // track expected arrival timme
3371                 conn->sco_rx_count++;
3372                 conn->sco_rx_ms += 7;
3373                 int delta = (int32_t) (now - conn->sco_rx_ms);
3374                 if (delta > 0){
3375                     conn->sco_rx_ms++;
3376                 }
3377                 // log_debug("sco rx %u", conn->sco_rx_ms);
3378                 sco_schedule_tx(conn);
3379             }
3380         }
3381     }
3382 #endif
3383 
3384     // deliver to app
3385     if (hci_stack->sco_packet_handler) {
3386         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3387     }
3388 
3389 #ifdef HAVE_SCO_TRANSPORT
3390     // We can send one packet for each received packet
3391     conn->sco_tx_ready++;
3392     hci_notify_if_sco_can_send_now();
3393 #endif
3394 
3395 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3396     conn->num_packets_completed++;
3397     hci_stack->host_completed_packets = 1;
3398     hci_run();
3399 #endif
3400 }
3401 #endif
3402 
3403 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3404     hci_dump_packet(packet_type, 1, packet, size);
3405     switch (packet_type) {
3406         case HCI_EVENT_PACKET:
3407             event_handler(packet, size);
3408             break;
3409         case HCI_ACL_DATA_PACKET:
3410             acl_handler(packet, size);
3411             break;
3412 #ifdef ENABLE_CLASSIC
3413         case HCI_SCO_DATA_PACKET:
3414             sco_handler(packet, size);
3415             break;
3416 #endif
3417         default:
3418             break;
3419     }
3420 }
3421 
3422 /**
3423  * @brief Add event packet handler.
3424  */
3425 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3426     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3427 }
3428 
3429 /**
3430  * @brief Remove event packet handler.
3431  */
3432 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3433     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3434 }
3435 
3436 /** Register HCI packet handlers */
3437 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3438     hci_stack->acl_packet_handler = handler;
3439 }
3440 
3441 #ifdef ENABLE_CLASSIC
3442 /**
3443  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3444  */
3445 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3446     hci_stack->sco_packet_handler = handler;
3447 }
3448 #endif
3449 
3450 static void hci_state_reset(void){
3451     // no connections yet
3452     hci_stack->connections = NULL;
3453 
3454     // keep discoverable/connectable as this has been requested by the client(s)
3455     // hci_stack->discoverable = 0;
3456     // hci_stack->connectable = 0;
3457     // hci_stack->bondable = 1;
3458     // hci_stack->own_addr_type = 0;
3459 
3460     // buffer is free
3461     hci_stack->hci_packet_buffer_reserved = false;
3462 
3463     // no pending cmds
3464     hci_stack->decline_reason = 0;
3465 
3466     hci_stack->secure_connections_active = false;
3467 
3468 #ifdef ENABLE_CLASSIC
3469     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3470     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3471 
3472     hci_stack->gap_tasks =
3473             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3474             GAP_TASK_SET_CLASS_OF_DEVICE |
3475             GAP_TASK_SET_LOCAL_NAME |
3476             GAP_TASK_SET_EIR_DATA |
3477             GAP_TASK_WRITE_SCAN_ENABLE |
3478             GAP_TASK_WRITE_PAGE_TIMEOUT;
3479 #endif
3480 
3481 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3482     hci_stack->classic_read_local_oob_data = false;
3483     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3484 #endif
3485 
3486     // LE
3487 #ifdef ENABLE_BLE
3488     memset(hci_stack->le_random_address, 0, 6);
3489     hci_stack->le_random_address_set = 0;
3490 #endif
3491 #ifdef ENABLE_LE_CENTRAL
3492     hci_stack->le_scanning_active  = false;
3493     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3494     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3495     hci_stack->le_whitelist_capacity = 0;
3496 #endif
3497 #ifdef ENABLE_LE_PERIPHERAL
3498     hci_stack->le_advertisements_active = false;
3499     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3500         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3501     }
3502     if (hci_stack->le_advertisements_data != NULL){
3503         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3504     }
3505 #endif
3506 }
3507 
3508 #ifdef ENABLE_CLASSIC
3509 /**
3510  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3511  */
3512 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3513     // store and open remote device db
3514     hci_stack->link_key_db = link_key_db;
3515     if (hci_stack->link_key_db) {
3516         hci_stack->link_key_db->open();
3517     }
3518 }
3519 #endif
3520 
3521 void hci_init(const hci_transport_t *transport, const void *config){
3522 
3523 #ifdef HAVE_MALLOC
3524     if (!hci_stack) {
3525         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3526     }
3527 #else
3528     hci_stack = &hci_stack_static;
3529 #endif
3530     memset(hci_stack, 0, sizeof(hci_stack_t));
3531 
3532     // reference to use transport layer implementation
3533     hci_stack->hci_transport = transport;
3534 
3535     // reference to used config
3536     hci_stack->config = config;
3537 
3538     // setup pointer for outgoing packet buffer
3539     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3540 
3541     // max acl payload size defined in config.h
3542     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3543 
3544     // register packet handlers with transport
3545     transport->register_packet_handler(&packet_handler);
3546 
3547     hci_stack->state = HCI_STATE_OFF;
3548 
3549     // class of device
3550     hci_stack->class_of_device = 0x007a020c; // Smartphone
3551 
3552     // bondable by default
3553     hci_stack->bondable = 1;
3554 
3555 #ifdef ENABLE_CLASSIC
3556     // classic name
3557     hci_stack->local_name = default_classic_name;
3558 
3559     // Master slave policy
3560     hci_stack->master_slave_policy = 1;
3561 
3562     // Allow Role Switch
3563     hci_stack->allow_role_switch = 1;
3564 
3565     // Default / minimum security level = 2
3566     hci_stack->gap_security_level = LEVEL_2;
3567 
3568     // Default Security Mode 4
3569     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3570 
3571     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3572     hci_stack->gap_required_encyrption_key_size = 7;
3573 
3574     // Link Supervision Timeout
3575     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3576 
3577 #endif
3578 
3579     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3580     hci_stack->ssp_enable = 1;
3581     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3582     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3583     hci_stack->ssp_auto_accept = 1;
3584 
3585     // Secure Connections: enable (requires support from Controller)
3586     hci_stack->secure_connections_enable = true;
3587 
3588     // voice setting - signed 16 bit pcm data with CVSD over the air
3589     hci_stack->sco_voice_setting = 0x60;
3590 
3591 #ifdef ENABLE_LE_CENTRAL
3592     // connection parameter to use for outgoing connections
3593     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3594     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3595     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3596     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3597     hci_stack->le_connection_latency      = 4;         // 4
3598     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3599     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3600     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3601 
3602     // default LE Scanning
3603     hci_stack->le_scan_type     =   0x1; // active
3604     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3605     hci_stack->le_scan_window   =  0x30; //  30 ms
3606 #endif
3607 
3608 #ifdef ENABLE_LE_PERIPHERAL
3609     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3610 #endif
3611 
3612     // connection parameter range used to answer connection parameter update requests in l2cap
3613     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3614     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3615     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3616     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3617     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3618     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3619 
3620     hci_state_reset();
3621 }
3622 
3623 void hci_deinit(void){
3624 #ifdef HAVE_MALLOC
3625     if (hci_stack) {
3626         free(hci_stack);
3627     }
3628 #endif
3629     hci_stack = NULL;
3630 
3631 #ifdef ENABLE_CLASSIC
3632     disable_l2cap_timeouts = 0;
3633 #endif
3634 }
3635 
3636 /**
3637  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3638  */
3639 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3640     hci_stack->chipset = chipset_driver;
3641 
3642     // reset chipset driver - init is also called on power_up
3643     if (hci_stack->chipset && hci_stack->chipset->init){
3644         hci_stack->chipset->init(hci_stack->config);
3645     }
3646 }
3647 
3648 /**
3649  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3650  */
3651 void hci_set_control(const btstack_control_t *hardware_control){
3652     // references to used control implementation
3653     hci_stack->control = hardware_control;
3654     // init with transport config
3655     hardware_control->init(hci_stack->config);
3656 }
3657 
3658 static void hci_discard_connections(void){
3659     btstack_linked_list_iterator_t lit;
3660     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3661     while (btstack_linked_list_iterator_has_next(&lit)){
3662         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3663         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3664         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3665         hci_shutdown_connection(connection);
3666     }
3667 }
3668 
3669 void hci_close(void){
3670 
3671 #ifdef ENABLE_CLASSIC
3672     // close remote device db
3673     if (hci_stack->link_key_db) {
3674         hci_stack->link_key_db->close();
3675     }
3676 #endif
3677 
3678     hci_discard_connections();
3679 
3680     hci_power_control(HCI_POWER_OFF);
3681 
3682 #ifdef HAVE_MALLOC
3683     free(hci_stack);
3684 #endif
3685     hci_stack = NULL;
3686 }
3687 
3688 #ifdef HAVE_SCO_TRANSPORT
3689 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3690     hci_stack->sco_transport = sco_transport;
3691     sco_transport->register_packet_handler(&packet_handler);
3692 }
3693 #endif
3694 
3695 #ifdef ENABLE_CLASSIC
3696 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3697     // validate ranage and set
3698     if (encryption_key_size < 7)  return;
3699     if (encryption_key_size > 16) return;
3700     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3701 }
3702 
3703 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3704     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3705         hci_stack->gap_security_mode = security_mode;
3706         return ERROR_CODE_SUCCESS;
3707     } else {
3708         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3709     }
3710 }
3711 
3712 gap_security_mode_t gap_get_security_mode(void){
3713     return hci_stack->gap_security_mode;
3714 }
3715 
3716 void gap_set_security_level(gap_security_level_t security_level){
3717     hci_stack->gap_security_level = security_level;
3718 }
3719 
3720 gap_security_level_t gap_get_security_level(void){
3721     if (hci_stack->gap_secure_connections_only_mode){
3722         return LEVEL_4;
3723     }
3724     return hci_stack->gap_security_level;
3725 }
3726 
3727 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3728     hci_stack->gap_minimal_service_security_level = security_level;
3729 }
3730 
3731 void gap_set_secure_connections_only_mode(bool enable){
3732     hci_stack->gap_secure_connections_only_mode = enable;
3733 }
3734 
3735 bool gap_get_secure_connections_only_mode(void){
3736     return hci_stack->gap_secure_connections_only_mode;
3737 }
3738 #endif
3739 
3740 #ifdef ENABLE_CLASSIC
3741 void gap_set_class_of_device(uint32_t class_of_device){
3742     hci_stack->class_of_device = class_of_device;
3743     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3744     hci_run();
3745 }
3746 
3747 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3748     hci_stack->default_link_policy_settings = default_link_policy_settings;
3749     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3750     hci_run();
3751 }
3752 
3753 void gap_set_allow_role_switch(bool allow_role_switch){
3754     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3755 }
3756 
3757 uint8_t hci_get_allow_role_switch(void){
3758     return  hci_stack->allow_role_switch;
3759 }
3760 
3761 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3762     hci_stack->link_supervision_timeout = link_supervision_timeout;
3763 }
3764 
3765 void hci_disable_l2cap_timeout_check(void){
3766     disable_l2cap_timeouts = 1;
3767 }
3768 #endif
3769 
3770 #ifndef HAVE_HOST_CONTROLLER_API
3771 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3772 void hci_set_bd_addr(bd_addr_t addr){
3773     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3774     hci_stack->custom_bd_addr_set = 1;
3775 }
3776 #endif
3777 
3778 // State-Module-Driver overview
3779 // state                    module  low-level
3780 // HCI_STATE_OFF             off      close
3781 // HCI_STATE_INITIALIZING,   on       open
3782 // HCI_STATE_WORKING,        on       open
3783 // HCI_STATE_HALTING,        on       open
3784 // HCI_STATE_SLEEPING,    off/sleep   close
3785 // HCI_STATE_FALLING_ASLEEP  on       open
3786 
3787 static int hci_power_control_on(void){
3788 
3789     // power on
3790     int err = 0;
3791     if (hci_stack->control && hci_stack->control->on){
3792         err = (*hci_stack->control->on)();
3793     }
3794     if (err){
3795         log_error( "POWER_ON failed");
3796         hci_emit_hci_open_failed();
3797         return err;
3798     }
3799 
3800     // int chipset driver
3801     if (hci_stack->chipset && hci_stack->chipset->init){
3802         hci_stack->chipset->init(hci_stack->config);
3803     }
3804 
3805     // init transport
3806     if (hci_stack->hci_transport->init){
3807         hci_stack->hci_transport->init(hci_stack->config);
3808     }
3809 
3810     // open transport
3811     err = hci_stack->hci_transport->open();
3812     if (err){
3813         log_error( "HCI_INIT failed, turning Bluetooth off again");
3814         if (hci_stack->control && hci_stack->control->off){
3815             (*hci_stack->control->off)();
3816         }
3817         hci_emit_hci_open_failed();
3818         return err;
3819     }
3820     return 0;
3821 }
3822 
3823 static void hci_power_control_off(void){
3824 
3825     log_info("hci_power_control_off");
3826 
3827     // close low-level device
3828     hci_stack->hci_transport->close();
3829 
3830     log_info("hci_power_control_off - hci_transport closed");
3831 
3832     // power off
3833     if (hci_stack->control && hci_stack->control->off){
3834         (*hci_stack->control->off)();
3835     }
3836 
3837     log_info("hci_power_control_off - control closed");
3838 
3839     hci_stack->state = HCI_STATE_OFF;
3840 }
3841 
3842 static void hci_power_control_sleep(void){
3843 
3844     log_info("hci_power_control_sleep");
3845 
3846 #if 0
3847     // don't close serial port during sleep
3848 
3849     // close low-level device
3850     hci_stack->hci_transport->close(hci_stack->config);
3851 #endif
3852 
3853     // sleep mode
3854     if (hci_stack->control && hci_stack->control->sleep){
3855         (*hci_stack->control->sleep)();
3856     }
3857 
3858     hci_stack->state = HCI_STATE_SLEEPING;
3859 }
3860 
3861 static int hci_power_control_wake(void){
3862 
3863     log_info("hci_power_control_wake");
3864 
3865     // wake on
3866     if (hci_stack->control && hci_stack->control->wake){
3867         (*hci_stack->control->wake)();
3868     }
3869 
3870 #if 0
3871     // open low-level device
3872     int err = hci_stack->hci_transport->open(hci_stack->config);
3873     if (err){
3874         log_error( "HCI_INIT failed, turning Bluetooth off again");
3875         if (hci_stack->control && hci_stack->control->off){
3876             (*hci_stack->control->off)();
3877         }
3878         hci_emit_hci_open_failed();
3879         return err;
3880     }
3881 #endif
3882 
3883     return 0;
3884 }
3885 
3886 static void hci_power_transition_to_initializing(void){
3887     // set up state machine
3888     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3889     hci_stack->hci_packet_buffer_reserved = false;
3890     hci_stack->state = HCI_STATE_INITIALIZING;
3891     hci_stack->substate = HCI_INIT_SEND_RESET;
3892 }
3893 
3894 // returns error
3895 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3896     int err;
3897     switch (power_mode){
3898         case HCI_POWER_ON:
3899             err = hci_power_control_on();
3900             if (err != 0) {
3901                 log_error("hci_power_control_on() error %d", err);
3902                 return err;
3903             }
3904             hci_power_transition_to_initializing();
3905             break;
3906         case HCI_POWER_OFF:
3907             // do nothing
3908             break;
3909         case HCI_POWER_SLEEP:
3910             // do nothing (with SLEEP == OFF)
3911             break;
3912         default:
3913             btstack_assert(false);
3914             break;
3915     }
3916     return ERROR_CODE_SUCCESS;
3917 }
3918 
3919 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3920     switch (power_mode){
3921         case HCI_POWER_ON:
3922             // do nothing
3923             break;
3924         case HCI_POWER_OFF:
3925             // no connections yet, just turn it off
3926             hci_power_control_off();
3927             break;
3928         case HCI_POWER_SLEEP:
3929             // no connections yet, just turn it off
3930             hci_power_control_sleep();
3931             break;
3932         default:
3933             btstack_assert(false);
3934             break;
3935     }
3936     return ERROR_CODE_SUCCESS;
3937 }
3938 
3939 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3940     switch (power_mode){
3941         case HCI_POWER_ON:
3942             // do nothing
3943             break;
3944         case HCI_POWER_OFF:
3945             // see hci_run
3946             hci_stack->state = HCI_STATE_HALTING;
3947             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3948             // setup watchdog timer for disconnect - only triggers if Controller does not respond anymore
3949             btstack_run_loop_set_timer(&hci_stack->timeout, 1000);
3950             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3951             btstack_run_loop_add_timer(&hci_stack->timeout);
3952             break;
3953         case HCI_POWER_SLEEP:
3954             // see hci_run
3955             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3956             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3957             break;
3958         default:
3959             btstack_assert(false);
3960             break;
3961     }
3962     return ERROR_CODE_SUCCESS;
3963 }
3964 
3965 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3966     switch (power_mode){
3967         case HCI_POWER_ON:
3968             hci_power_transition_to_initializing();
3969             break;
3970         case HCI_POWER_OFF:
3971             // do nothing
3972             break;
3973         case HCI_POWER_SLEEP:
3974             // see hci_run
3975             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3976             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3977             break;
3978         default:
3979             btstack_assert(false);
3980             break;
3981     }
3982     return ERROR_CODE_SUCCESS;
3983 }
3984 
3985 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3986     switch (power_mode){
3987         case HCI_POWER_ON:
3988             hci_power_transition_to_initializing();
3989             break;
3990         case HCI_POWER_OFF:
3991             // see hci_run
3992             hci_stack->state = HCI_STATE_HALTING;
3993             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3994             break;
3995         case HCI_POWER_SLEEP:
3996             // do nothing
3997             break;
3998         default:
3999             btstack_assert(false);
4000             break;
4001     }
4002     return ERROR_CODE_SUCCESS;
4003 }
4004 
4005 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4006     int err;
4007     switch (power_mode){
4008         case HCI_POWER_ON:
4009             err = hci_power_control_wake();
4010             if (err) return err;
4011             hci_power_transition_to_initializing();
4012             break;
4013         case HCI_POWER_OFF:
4014             hci_stack->state = HCI_STATE_HALTING;
4015             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4016             break;
4017         case HCI_POWER_SLEEP:
4018             // do nothing
4019             break;
4020         default:
4021             btstack_assert(false);
4022             break;
4023     }
4024     return ERROR_CODE_SUCCESS;
4025 }
4026 
4027 int hci_power_control(HCI_POWER_MODE power_mode){
4028     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4029     int err = 0;
4030     switch (hci_stack->state){
4031         case HCI_STATE_OFF:
4032             err = hci_power_control_state_off(power_mode);
4033             break;
4034         case HCI_STATE_INITIALIZING:
4035             err = hci_power_control_state_initializing(power_mode);
4036             break;
4037         case HCI_STATE_WORKING:
4038             err = hci_power_control_state_working(power_mode);
4039             break;
4040         case HCI_STATE_HALTING:
4041             err = hci_power_control_state_halting(power_mode);
4042             break;
4043         case HCI_STATE_FALLING_ASLEEP:
4044             err = hci_power_control_state_falling_asleep(power_mode);
4045             break;
4046         case HCI_STATE_SLEEPING:
4047             err = hci_power_control_state_sleeping(power_mode);
4048             break;
4049         default:
4050             btstack_assert(false);
4051             break;
4052     }
4053     if (err != 0){
4054         return err;
4055     }
4056 
4057     // create internal event
4058 	hci_emit_state();
4059 
4060 	// trigger next/first action
4061 	hci_run();
4062 
4063     return 0;
4064 }
4065 
4066 
4067 static void hci_halting_run(void){
4068 
4069     log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4070 
4071     hci_connection_t * connection;
4072 
4073     switch (hci_stack->substate) {
4074         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4075             case HCI_HALTING_DISCONNECT_ALL_TIMER:
4076 
4077 #ifdef ENABLE_BLE
4078 #ifdef ENABLE_LE_CENTRAL
4079     hci_whitelist_free();
4080 #endif
4081 #endif
4082     // close all open connections
4083     connection = (hci_connection_t *) hci_stack->connections;
4084     if (connection) {
4085         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4086         if (!hci_can_send_command_packet_now()) return;
4087 
4088         // check state
4089         if (connection->state == SENT_DISCONNECT) return;
4090         connection->state = SENT_DISCONNECT;
4091 
4092         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4093 
4094         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4095         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4096 
4097         // ... which would be ignored anyway as we shutdown (free) the connection now
4098         hci_shutdown_connection(connection);
4099 
4100         // finally, send the disconnect command
4101         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4102         return;
4103     }
4104 
4105     btstack_run_loop_remove_timer(&hci_stack->timeout);
4106 
4107     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER) {
4108         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4109         log_info("HCI_STATE_HALTING: wait 50 ms");
4110         hci_stack->substate = HCI_HALTING_W4_TIMER;
4111         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4112         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4113         btstack_run_loop_add_timer(&hci_stack->timeout);
4114         break;
4115     }
4116 
4117     /* fall through */
4118 
4119     case HCI_HALTING_CLOSE:
4120         // close left over connections (that had not been properly closed before)
4121         hci_discard_connections();
4122 
4123         log_info("HCI_STATE_HALTING, calling off");
4124 
4125         // switch mode
4126         hci_power_control_off();
4127 
4128         log_info("HCI_STATE_HALTING, emitting state");
4129         hci_emit_state();
4130         log_info("HCI_STATE_HALTING, done");
4131         break;
4132 
4133         case HCI_HALTING_W4_TIMER:
4134             // keep waiting
4135 
4136             break;
4137         default:
4138             break;
4139     }
4140 };
4141 
4142 static void hci_falling_asleep_run(void){
4143     hci_connection_t * connection;
4144     switch(hci_stack->substate) {
4145         case HCI_FALLING_ASLEEP_DISCONNECT:
4146             log_info("HCI_STATE_FALLING_ASLEEP");
4147             // close all open connections
4148             connection =  (hci_connection_t *) hci_stack->connections;
4149             if (connection){
4150 
4151                 // send disconnect
4152                 if (!hci_can_send_command_packet_now()) return;
4153 
4154                 log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4155                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4156 
4157                 // send disconnected event right away - causes higher layer connections to get closed, too.
4158                 hci_shutdown_connection(connection);
4159                 return;
4160             }
4161 
4162             if (hci_classic_supported()){
4163                 // disable page and inquiry scan
4164                 if (!hci_can_send_command_packet_now()) return;
4165 
4166                 log_info("HCI_STATE_HALTING, disabling inq scans");
4167                 hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4168 
4169                 // continue in next sub state
4170                 hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4171                 break;
4172             }
4173 
4174             /* fall through */
4175 
4176             case HCI_FALLING_ASLEEP_COMPLETE:
4177                 log_info("HCI_STATE_HALTING, calling sleep");
4178                 // switch mode
4179                 hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4180                 hci_emit_state();
4181                 break;
4182 
4183                 default:
4184                     break;
4185     }
4186 }
4187 
4188 #ifdef ENABLE_CLASSIC
4189 
4190 static void hci_update_scan_enable(void){
4191     // 2 = page scan, 1 = inq scan
4192     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4193     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4194     hci_run();
4195 }
4196 
4197 void gap_discoverable_control(uint8_t enable){
4198     if (enable) enable = 1; // normalize argument
4199 
4200     if (hci_stack->discoverable == enable){
4201         hci_emit_discoverable_enabled(hci_stack->discoverable);
4202         return;
4203     }
4204 
4205     hci_stack->discoverable = enable;
4206     hci_update_scan_enable();
4207 }
4208 
4209 void gap_connectable_control(uint8_t enable){
4210     if (enable) enable = 1; // normalize argument
4211 
4212     // don't emit event
4213     if (hci_stack->connectable == enable) return;
4214 
4215     hci_stack->connectable = enable;
4216     hci_update_scan_enable();
4217 }
4218 #endif
4219 
4220 void gap_local_bd_addr(bd_addr_t address_buffer){
4221     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4222 }
4223 
4224 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4225 static void hci_host_num_completed_packets(void){
4226 
4227     // create packet manually as arrays are not supported and num_commands should not get reduced
4228     hci_reserve_packet_buffer();
4229     uint8_t * packet = hci_get_outgoing_packet_buffer();
4230 
4231     uint16_t size = 0;
4232     uint16_t num_handles = 0;
4233     packet[size++] = 0x35;
4234     packet[size++] = 0x0c;
4235     size++;  // skip param len
4236     size++;  // skip num handles
4237 
4238     // add { handle, packets } entries
4239     btstack_linked_item_t * it;
4240     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4241         hci_connection_t * connection = (hci_connection_t *) it;
4242         if (connection->num_packets_completed){
4243             little_endian_store_16(packet, size, connection->con_handle);
4244             size += 2;
4245             little_endian_store_16(packet, size, connection->num_packets_completed);
4246             size += 2;
4247             //
4248             num_handles++;
4249             connection->num_packets_completed = 0;
4250         }
4251     }
4252 
4253     packet[2] = size - 3;
4254     packet[3] = num_handles;
4255 
4256     hci_stack->host_completed_packets = 0;
4257 
4258     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4259     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4260 
4261     // release packet buffer for synchronous transport implementations
4262     if (hci_transport_synchronous()){
4263         hci_release_packet_buffer();
4264         hci_emit_transport_packet_sent();
4265     }
4266 }
4267 #endif
4268 
4269 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4270     UNUSED(ds);
4271     hci_stack->substate = HCI_HALTING_CLOSE;
4272     // allow packet handlers to defer final shutdown
4273     hci_emit_state();
4274     hci_run();
4275 }
4276 
4277 static bool hci_run_acl_fragments(void){
4278     if (hci_stack->acl_fragmentation_total_size > 0u) {
4279         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4280         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4281         if (connection) {
4282             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4283                 hci_send_acl_packet_fragments(connection);
4284                 return true;
4285             }
4286         } else {
4287             // connection gone -> discard further fragments
4288             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4289             hci_stack->acl_fragmentation_total_size = 0;
4290             hci_stack->acl_fragmentation_pos = 0;
4291         }
4292     }
4293     return false;
4294 }
4295 
4296 #ifdef ENABLE_CLASSIC
4297 static bool hci_run_general_gap_classic(void){
4298 
4299     // assert stack is working and classic is active
4300     if (hci_classic_supported() == false)      return false;
4301     if (hci_stack->state != HCI_STATE_WORKING) return false;
4302 
4303     // decline incoming connections
4304     if (hci_stack->decline_reason){
4305         uint8_t reason = hci_stack->decline_reason;
4306         hci_stack->decline_reason = 0;
4307         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4308         return true;
4309     }
4310 
4311     if (hci_stack->gap_tasks != 0){
4312         hci_run_gap_tasks_classic();
4313         return true;
4314     }
4315 
4316     // start/stop inquiry
4317     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4318         uint8_t duration = hci_stack->inquiry_state;
4319         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4320         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4321         return true;
4322     }
4323     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4324         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4325         hci_send_cmd(&hci_inquiry_cancel);
4326         return true;
4327     }
4328     // remote name request
4329     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4330         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4331         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4332                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4333         return true;
4334     }
4335 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4336     // Local OOB data
4337     if (hci_stack->classic_read_local_oob_data){
4338         hci_stack->classic_read_local_oob_data = false;
4339         if (hci_stack->local_supported_commands[1] & 0x10u){
4340             hci_send_cmd(&hci_read_local_extended_oob_data);
4341         } else {
4342             hci_send_cmd(&hci_read_local_oob_data);
4343         }
4344     }
4345 #endif
4346     // pairing
4347     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4348         uint8_t state = hci_stack->gap_pairing_state;
4349         uint8_t pin_code[16];
4350         switch (state){
4351             case GAP_PAIRING_STATE_SEND_PIN:
4352                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4353                 memset(pin_code, 0, 16);
4354                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4355                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4356                 break;
4357             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4358                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4359                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4360                 break;
4361             case GAP_PAIRING_STATE_SEND_PASSKEY:
4362                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4363                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4364                 break;
4365             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4366                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4367                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4368                 break;
4369             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4370                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4371                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4372                 break;
4373             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4374                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4375                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4376                 break;
4377             default:
4378                 break;
4379         }
4380         return true;
4381     }
4382     return false;
4383 }
4384 #endif
4385 
4386 #ifdef ENABLE_BLE
4387 static bool hci_run_general_gap_le(void){
4388 
4389     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4390 
4391     if (hci_stack->state != HCI_STATE_WORKING) return false;
4392     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4393 
4394 
4395     // Phase 1: collect what to stop
4396 
4397     bool scanning_stop = false;
4398     bool connecting_stop = false;
4399     bool advertising_stop = false;
4400 
4401 #ifndef ENABLE_LE_CENTRAL
4402     UNUSED(scanning_stop);
4403     UNUSED(connecting_stop);
4404 #endif
4405 #ifndef ENABLE_LE_PERIPHERAL
4406     UNUSED(advertising_stop);
4407 #endif
4408 
4409     // check if own address changes
4410     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4411 
4412     // check if whitelist needs modification
4413     bool whitelist_modification_pending = false;
4414     btstack_linked_list_iterator_t lit;
4415     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4416     while (btstack_linked_list_iterator_has_next(&lit)){
4417         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4418         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4419             whitelist_modification_pending = true;
4420             break;
4421         }
4422     }
4423     // check if resolving list needs modification
4424     bool resolving_list_modification_pending = false;
4425 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4426     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4427 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4428         resolving_list_modification_pending = true;
4429     }
4430 #endif
4431 
4432 #ifdef ENABLE_LE_CENTRAL
4433     // scanning control
4434     if (hci_stack->le_scanning_active) {
4435         // stop if:
4436         // - parameter change required
4437         // - it's disabled
4438         // - whitelist change required but used for scanning
4439         // - resolving list modified
4440         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4441         if ((hci_stack->le_scanning_param_update) ||
4442             !hci_stack->le_scanning_enabled ||
4443             scanning_uses_whitelist ||
4444             resolving_list_modification_pending){
4445 
4446             scanning_stop = true;
4447         }
4448     }
4449 #endif
4450 
4451 #ifdef ENABLE_LE_CENTRAL
4452     // connecting control
4453     bool connecting_with_whitelist;
4454     switch (hci_stack->le_connecting_state){
4455         case LE_CONNECTING_DIRECT:
4456         case LE_CONNECTING_WHITELIST:
4457             // stop connecting if:
4458             // - connecting uses white and whitelist modification pending
4459             // - if it got disabled
4460             // - resolving list modified
4461             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4462             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4463                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4464                 resolving_list_modification_pending) {
4465 
4466                 connecting_stop = true;
4467             }
4468             break;
4469         default:
4470             break;
4471     }
4472 #endif
4473 
4474 #ifdef ENABLE_LE_PERIPHERAL
4475     // le advertisement control
4476     if (hci_stack->le_advertisements_active){
4477         // stop if:
4478         // - parameter change required
4479         // - random address used in advertising and changes
4480         // - it's disabled
4481         // - whitelist change required but used for advertisement filter policy
4482         // - resolving list modified
4483         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4484         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4485         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4486         if (advertising_change ||
4487             (advertising_uses_random_address && random_address_change) ||
4488             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4489             (advertising_uses_whitelist && whitelist_modification_pending) ||
4490             resolving_list_modification_pending) {
4491 
4492             advertising_stop = true;
4493         }
4494     }
4495 #endif
4496 
4497 
4498     // Phase 2: stop everything that should be off during modifications
4499 
4500 #ifdef ENABLE_LE_CENTRAL
4501     if (scanning_stop){
4502         hci_stack->le_scanning_active = false;
4503         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4504         return true;
4505     }
4506 #endif
4507 
4508 #ifdef ENABLE_LE_CENTRAL
4509     if (connecting_stop){
4510         hci_send_cmd(&hci_le_create_connection_cancel);
4511         return true;
4512     }
4513 #endif
4514 
4515 #ifdef ENABLE_LE_PERIPHERAL
4516     if (advertising_stop){
4517         hci_stack->le_advertisements_active = false;
4518         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4519         return true;
4520     }
4521 #endif
4522 
4523     // Phase 3: modify
4524 
4525     if (random_address_change){
4526         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4527         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4528         return true;
4529     }
4530 
4531 #ifdef ENABLE_LE_CENTRAL
4532     if (hci_stack->le_scanning_param_update){
4533         hci_stack->le_scanning_param_update = false;
4534         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4535                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4536         return true;
4537     }
4538 #endif
4539 
4540 #ifdef ENABLE_LE_PERIPHERAL
4541     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4542         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4543         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4544         hci_send_cmd(&hci_le_set_advertising_parameters,
4545                      hci_stack->le_advertisements_interval_min,
4546                      hci_stack->le_advertisements_interval_max,
4547                      hci_stack->le_advertisements_type,
4548                      hci_stack->le_advertisements_own_addr_type,
4549                      hci_stack->le_advertisements_direct_address_type,
4550                      hci_stack->le_advertisements_direct_address,
4551                      hci_stack->le_advertisements_channel_map,
4552                      hci_stack->le_advertisements_filter_policy);
4553         return true;
4554     }
4555     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4556         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4557         uint8_t adv_data_clean[31];
4558         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4559         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4560                      hci_stack->le_advertisements_data_len);
4561         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4562         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4563         return true;
4564     }
4565     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4566         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4567         uint8_t scan_data_clean[31];
4568         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4569         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4570                      hci_stack->le_scan_response_data_len);
4571         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4572         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4573         return true;
4574     }
4575 #endif
4576 
4577 
4578 #ifdef ENABLE_LE_CENTRAL
4579     // if connect with whitelist was active and is not cancelled yet, wait until next time
4580     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4581 #endif
4582 
4583     // LE Whitelist Management
4584     if (whitelist_modification_pending){
4585         // add/remove entries
4586         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4587         while (btstack_linked_list_iterator_has_next(&lit)){
4588             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4589 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4590 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4591 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4592 				return true;
4593 			}
4594             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4595 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4596                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4597                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4598                 return true;
4599             }
4600             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4601 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4602 				btstack_memory_whitelist_entry_free(entry);
4603             }
4604         }
4605     }
4606 
4607 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4608     // LE Resolving List Management
4609     if (resolving_list_supported) {
4610 		uint16_t i;
4611 		switch (hci_stack->le_resolving_list_state) {
4612 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4613 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4614 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4615 				return true;
4616 			case LE_RESOLVING_LIST_READ_SIZE:
4617 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4618 				hci_send_cmd(&hci_le_read_resolving_list_size);
4619 				return true;
4620 			case LE_RESOLVING_LIST_SEND_CLEAR:
4621 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4622 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4623 							  sizeof(hci_stack->le_resolving_list_add_entries));
4624 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4625 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4626 				hci_send_cmd(&hci_le_clear_resolving_list);
4627 				return true;
4628 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4629 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4630 					uint8_t offset = i >> 3;
4631 					uint8_t mask = 1 << (i & 7);
4632 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4633 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4634 					bd_addr_t peer_identity_addreses;
4635 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4636 					sm_key_t peer_irk;
4637 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4638 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4639 
4640 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4641 					// trigger whitelist entry 'update' (work around for controller bug)
4642 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4643 					while (btstack_linked_list_iterator_has_next(&lit)) {
4644 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4645 						if (entry->address_type != peer_identity_addr_type) continue;
4646 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4647 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4648 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4649 					}
4650 #endif
4651 
4652 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4653 								 peer_identity_addreses);
4654 					return true;
4655 				}
4656 
4657 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4658 
4659 				/* fall through */
4660 
4661 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4662 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4663 					uint8_t offset = i >> 3;
4664 					uint8_t mask = 1 << (i & 7);
4665 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4666 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4667 					bd_addr_t peer_identity_addreses;
4668 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4669 					sm_key_t peer_irk;
4670 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4671 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4672 					const uint8_t *local_irk = gap_get_persistent_irk();
4673 					// command uses format specifier 'P' that stores 16-byte value without flip
4674 					uint8_t local_irk_flipped[16];
4675 					uint8_t peer_irk_flipped[16];
4676 					reverse_128(local_irk, local_irk_flipped);
4677 					reverse_128(peer_irk, peer_irk_flipped);
4678 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4679 								 peer_irk_flipped, local_irk_flipped);
4680 					return true;
4681 				}
4682 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4683 				break;
4684 
4685 			default:
4686 				break;
4687 		}
4688 	}
4689     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4690 #endif
4691 
4692     // Phase 4: restore state
4693 
4694 #ifdef ENABLE_LE_CENTRAL
4695     // re-start scanning
4696     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4697         hci_stack->le_scanning_active = true;
4698         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4699         return true;
4700     }
4701 #endif
4702 
4703 #ifdef ENABLE_LE_CENTRAL
4704     // re-start connecting
4705     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4706         bd_addr_t null_addr;
4707         memset(null_addr, 0, 6);
4708         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4709         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4710         hci_send_cmd(&hci_le_create_connection,
4711                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4712                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4713                      1,         // use whitelist
4714                      0,         // peer address type
4715                      null_addr, // peer bd addr
4716                      hci_stack->le_connection_own_addr_type,   // our addr type:
4717                      hci_stack->le_connection_interval_min,    // conn interval min
4718                      hci_stack->le_connection_interval_max,    // conn interval max
4719                      hci_stack->le_connection_latency,         // conn latency
4720                      hci_stack->le_supervision_timeout,        // conn latency
4721                      hci_stack->le_minimum_ce_length,          // min ce length
4722                      hci_stack->le_maximum_ce_length           // max ce length
4723         );
4724         return true;
4725     }
4726 #endif
4727 
4728 #ifdef ENABLE_LE_PERIPHERAL
4729     // re-start advertising
4730     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4731         // check if advertisements should be enabled given
4732         hci_stack->le_advertisements_active = true;
4733         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4734         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4735         return true;
4736     }
4737 #endif
4738 
4739     return false;
4740 }
4741 #endif
4742 
4743 static bool hci_run_general_pending_commands(void){
4744     btstack_linked_item_t * it;
4745     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4746         hci_connection_t * connection = (hci_connection_t *) it;
4747 
4748         switch(connection->state){
4749             case SEND_CREATE_CONNECTION:
4750                 switch(connection->address_type){
4751 #ifdef ENABLE_CLASSIC
4752                     case BD_ADDR_TYPE_ACL:
4753                         log_info("sending hci_create_connection");
4754                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4755                         break;
4756 #endif
4757                     default:
4758 #ifdef ENABLE_BLE
4759 #ifdef ENABLE_LE_CENTRAL
4760                         log_info("sending hci_le_create_connection");
4761                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4762                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4763                         hci_send_cmd(&hci_le_create_connection,
4764                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4765                                      hci_stack->le_connection_scan_window,      // conn scan windows
4766                                      0,         // don't use whitelist
4767                                      connection->address_type, // peer address type
4768                                      connection->address,      // peer bd addr
4769                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4770                                      hci_stack->le_connection_interval_min,    // conn interval min
4771                                      hci_stack->le_connection_interval_max,    // conn interval max
4772                                      hci_stack->le_connection_latency,         // conn latency
4773                                      hci_stack->le_supervision_timeout,        // conn latency
4774                                      hci_stack->le_minimum_ce_length,          // min ce length
4775                                      hci_stack->le_maximum_ce_length          // max ce length
4776                         );
4777                         connection->state = SENT_CREATE_CONNECTION;
4778 #endif
4779 #endif
4780                         break;
4781                 }
4782                 return true;
4783 
4784 #ifdef ENABLE_CLASSIC
4785             case RECEIVED_CONNECTION_REQUEST:
4786                 connection->role  = HCI_ROLE_SLAVE;
4787                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4788                     log_info("sending hci_accept_connection_request");
4789                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4790                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4791                 }
4792                 return true;
4793 #endif
4794 
4795 #ifdef ENABLE_BLE
4796 #ifdef ENABLE_LE_CENTRAL
4797             case SEND_CANCEL_CONNECTION:
4798                 connection->state = SENT_CANCEL_CONNECTION;
4799                 hci_send_cmd(&hci_le_create_connection_cancel);
4800                 return true;
4801 #endif
4802 #endif
4803             case SEND_DISCONNECT:
4804                 connection->state = SENT_DISCONNECT;
4805                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4806                 return true;
4807 
4808             default:
4809                 break;
4810         }
4811 
4812         // no further commands if connection is about to get shut down
4813         if (connection->state == SENT_DISCONNECT) continue;
4814 
4815         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4816             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4817             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4818             return true;
4819         }
4820 
4821 #ifdef ENABLE_CLASSIC
4822 
4823         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4824             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4825             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4826             return true;
4827         }
4828 
4829         // Handling link key request requires remote supported features
4830         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4831             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4832             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4833 
4834             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4835             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4836             if (have_link_key && security_level_sufficient){
4837                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4838             } else {
4839                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4840             }
4841             return true;
4842         }
4843 
4844         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4845             log_info("denying to pin request");
4846             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4847             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4848             return true;
4849         }
4850 
4851         // security assessment requires remote features
4852         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4853             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4854             hci_ssp_assess_security_on_io_cap_request(connection);
4855             // 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
4856         }
4857 
4858         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4859             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4860             // set authentication requirements:
4861             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4862             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4863             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4864             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4865                 authreq |= 1;
4866             }
4867             bool bonding = hci_stack->bondable;
4868             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4869                 // if we have received IO Cap Response, we're in responder role
4870                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4871                 if (bonding && !remote_bonding){
4872                     log_info("Remote not bonding, dropping local flag");
4873                     bonding = false;
4874                 }
4875             }
4876             if (bonding){
4877                 if (connection->bonding_flags & BONDING_DEDICATED){
4878                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4879                 } else {
4880                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4881                 }
4882             }
4883             uint8_t have_oob_data = 0;
4884 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4885             if (connection->classic_oob_c_192 != NULL){
4886                     have_oob_data |= 1;
4887             }
4888             if (connection->classic_oob_c_256 != NULL){
4889                 have_oob_data |= 2;
4890             }
4891 #endif
4892             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4893             return true;
4894         }
4895 
4896         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4897             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4898             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4899             return true;
4900         }
4901 
4902 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4903         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4904             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4905             const uint8_t zero[16] = { 0 };
4906             const uint8_t * r_192 = zero;
4907             const uint8_t * c_192 = zero;
4908             const uint8_t * r_256 = zero;
4909             const uint8_t * c_256 = zero;
4910             // verify P-256 OOB
4911             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4912                 c_256 = connection->classic_oob_c_256;
4913                 if (connection->classic_oob_r_256 != NULL) {
4914                     r_256 = connection->classic_oob_r_256;
4915                 }
4916             }
4917             // verify P-192 OOB
4918             if ((connection->classic_oob_c_192 != NULL)) {
4919                 c_192 = connection->classic_oob_c_192;
4920                 if (connection->classic_oob_r_192 != NULL) {
4921                     r_192 = connection->classic_oob_r_192;
4922                 }
4923             }
4924 
4925             // assess security
4926             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4927             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4928             if (need_level_4 && !can_reach_level_4){
4929                 log_info("Level 4 required, but not possible -> abort");
4930                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4931                 // send oob negative reply
4932                 c_256 = NULL;
4933                 c_192 = NULL;
4934             }
4935 
4936             // Reply
4937             if (c_256 != zero) {
4938                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4939             } else if (c_192 != zero){
4940                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4941             } else {
4942                 hci_stack->classic_oob_con_handle = connection->con_handle;
4943                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4944             }
4945             return true;
4946         }
4947 #endif
4948 
4949         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4950             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4951             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4952             return true;
4953         }
4954 
4955         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4956             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4957             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4958             return true;
4959         }
4960 
4961         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4962             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4963             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4964             return true;
4965         }
4966 
4967         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4968             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4969             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4970             connection->state = SENT_DISCONNECT;
4971             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4972             return true;
4973         }
4974 
4975         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4976             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4977             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4978             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4979             return true;
4980         }
4981 
4982         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4983             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4984             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4985             return true;
4986         }
4987 
4988         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4989             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4990             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4991             return true;
4992         }
4993 
4994         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4995             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4996             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4997             return true;
4998         }
4999 
5000         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
5001             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
5002             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
5003             return true;
5004         }
5005 
5006         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
5007             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
5008             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
5009             return true;
5010         }
5011 #endif
5012 
5013         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
5014             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
5015 #ifdef ENABLE_CLASSIC
5016             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
5017 #endif
5018             if (connection->state != SENT_DISCONNECT){
5019                 connection->state = SENT_DISCONNECT;
5020                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
5021                 return true;
5022             }
5023         }
5024 
5025 #ifdef ENABLE_CLASSIC
5026         uint16_t sniff_min_interval;
5027         switch (connection->sniff_min_interval){
5028             case 0:
5029                 break;
5030             case 0xffff:
5031                 connection->sniff_min_interval = 0;
5032                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
5033                 return true;
5034             default:
5035                 sniff_min_interval = connection->sniff_min_interval;
5036                 connection->sniff_min_interval = 0;
5037                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
5038                 return true;
5039         }
5040 
5041         if (connection->sniff_subrating_max_latency != 0xffff){
5042             uint16_t max_latency = connection->sniff_subrating_max_latency;
5043             connection->sniff_subrating_max_latency = 0;
5044             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
5045             return true;
5046         }
5047 
5048         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
5049             uint8_t service_type = (uint8_t) connection->qos_service_type;
5050             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
5051             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);
5052             return true;
5053         }
5054 
5055         if (connection->request_role != HCI_ROLE_INVALID){
5056             hci_role_t role = connection->request_role;
5057             connection->request_role = HCI_ROLE_INVALID;
5058             hci_send_cmd(&hci_switch_role_command, connection->address, role);
5059             return true;
5060         }
5061 #endif
5062 
5063 #ifdef ENABLE_BLE
5064         switch (connection->le_con_parameter_update_state){
5065             // response to L2CAP CON PARAMETER UPDATE REQUEST
5066             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
5067                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5068                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
5069                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5070                              0x0000, 0xffff);
5071                 return true;
5072             case CON_PARAMETER_UPDATE_REPLY:
5073                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5074                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
5075                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
5076                              0x0000, 0xffff);
5077                 return true;
5078             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
5079                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
5080                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
5081                 return true;
5082             default:
5083                 break;
5084         }
5085         if (connection->le_phy_update_all_phys != 0xffu){
5086             uint8_t all_phys = connection->le_phy_update_all_phys;
5087             connection->le_phy_update_all_phys = 0xff;
5088             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);
5089             return true;
5090         }
5091 #endif
5092     }
5093     return false;
5094 }
5095 
5096 static void hci_run(void){
5097 
5098     // stack state sub statemachines
5099     // halting needs to be called even if we cannot send command packet now
5100     switch (hci_stack->state) {
5101         case HCI_STATE_INITIALIZING:
5102             hci_initializing_run();
5103             break;
5104         case HCI_STATE_HALTING:
5105             hci_halting_run();
5106             break;
5107         case HCI_STATE_FALLING_ASLEEP:
5108             hci_falling_asleep_run();
5109             break;
5110         default:
5111             break;
5112     }
5113 
5114     bool done;
5115 
5116     // send continuation fragments first, as they block the prepared packet buffer
5117     done = hci_run_acl_fragments();
5118     if (done) return;
5119 
5120 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
5121     // send host num completed packets next as they don't require num_cmd_packets > 0
5122     if (!hci_can_send_comand_packet_transport()) return;
5123     if (hci_stack->host_completed_packets){
5124         hci_host_num_completed_packets();
5125         return;
5126     }
5127 #endif
5128 
5129     if (!hci_can_send_command_packet_now()) return;
5130 
5131     // global/non-connection oriented commands
5132 
5133 
5134 #ifdef ENABLE_CLASSIC
5135     // general gap classic
5136     done = hci_run_general_gap_classic();
5137     if (done) return;
5138 #endif
5139 
5140 #ifdef ENABLE_BLE
5141     // general gap le
5142     done = hci_run_general_gap_le();
5143     if (done) return;
5144 #endif
5145 
5146     // send pending HCI commands
5147     hci_run_general_pending_commands();
5148 }
5149 
5150 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5151     // house-keeping
5152 
5153 #ifdef ENABLE_CLASSIC
5154     bd_addr_t addr;
5155     hci_connection_t * conn;
5156 #endif
5157 #ifdef ENABLE_LE_CENTRAL
5158     uint8_t initiator_filter_policy;
5159 #endif
5160 
5161     uint16_t opcode = little_endian_read_16(packet, 0);
5162     switch (opcode) {
5163         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5164             hci_stack->loopback_mode = packet[3];
5165             break;
5166 
5167 #ifdef ENABLE_CLASSIC
5168         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5169             reverse_bd_addr(&packet[3], addr);
5170             log_info("Create_connection to %s", bd_addr_to_str(addr));
5171 
5172             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5173             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5174                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5175                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5176             }
5177 
5178             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5179             if (!conn) {
5180                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5181                 if (!conn) {
5182                     // notify client that alloc failed
5183                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5184                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5185                 }
5186                 conn->state = SEND_CREATE_CONNECTION;
5187                 conn->role  = HCI_ROLE_MASTER;
5188             }
5189 
5190             conn->con_handle = HCI_CON_HANDLE_INVALID;
5191             conn->role = HCI_ROLE_INVALID;
5192 
5193             log_info("conn state %u", conn->state);
5194             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5195             switch (conn->state) {
5196                 // if connection active exists
5197                 case OPEN:
5198                     // and OPEN, emit connection complete command
5199                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5200                     // packet not sent to controller
5201                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5202                 case RECEIVED_DISCONNECTION_COMPLETE:
5203                     // create connection triggered in disconnect complete event, let's do it now
5204                     break;
5205                 case SEND_CREATE_CONNECTION:
5206                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5207                     break;
5208                 default:
5209                     // otherwise, just ignore as it is already in the open process
5210                     // packet not sent to controller
5211                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5212             }
5213             conn->state = SENT_CREATE_CONNECTION;
5214 
5215             // track outgoing connection
5216             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5217             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5218             break;
5219 
5220 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5221         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5222             // setup_synchronous_connection? Voice setting at offset 22
5223             // TODO: compare to current setting if sco connection already active
5224             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5225             break;
5226         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5227             // accept_synchronous_connection? Voice setting at offset 18
5228             // TODO: compare to current setting if sco connection already active
5229             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5230             break;
5231 #endif
5232 #endif
5233 
5234 #ifdef ENABLE_BLE
5235 #ifdef ENABLE_LE_CENTRAL
5236         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5237             // white list used?
5238             initiator_filter_policy = packet[7];
5239             switch (initiator_filter_policy) {
5240                 case 0:
5241                     // whitelist not used
5242                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5243                     break;
5244                 case 1:
5245                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5246                     break;
5247                 default:
5248                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5249                     break;
5250             }
5251             // track outgoing connection
5252             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5253             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5254             break;
5255         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5256             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5257             break;
5258 #endif
5259 #endif
5260         default:
5261             break;
5262     }
5263 
5264     hci_stack->num_cmd_packets--;
5265 
5266     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5267     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5268     if (err != 0){
5269         return ERROR_CODE_HARDWARE_FAILURE;
5270     }
5271     return ERROR_CODE_SUCCESS;
5272 }
5273 
5274 // disconnect because of security block
5275 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5276     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5277     if (!connection) return;
5278     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5279 }
5280 
5281 
5282 // Configure Secure Simple Pairing
5283 
5284 #ifdef ENABLE_CLASSIC
5285 
5286 // enable will enable SSP during init
5287 void gap_ssp_set_enable(int enable){
5288     hci_stack->ssp_enable = enable;
5289 }
5290 
5291 static int hci_local_ssp_activated(void){
5292     return gap_ssp_supported() && hci_stack->ssp_enable;
5293 }
5294 
5295 // if set, BTstack will respond to io capability request using authentication requirement
5296 void gap_ssp_set_io_capability(int io_capability){
5297     hci_stack->ssp_io_capability = io_capability;
5298 }
5299 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5300     hci_stack->ssp_authentication_requirement = authentication_requirement;
5301 }
5302 
5303 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5304 void gap_ssp_set_auto_accept(int auto_accept){
5305     hci_stack->ssp_auto_accept = auto_accept;
5306 }
5307 
5308 void gap_secure_connections_enable(bool enable){
5309     hci_stack->secure_connections_enable = enable;
5310 }
5311 
5312 #endif
5313 
5314 // va_list part of hci_send_cmd
5315 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5316     if (!hci_can_send_command_packet_now()){
5317         log_error("hci_send_cmd called but cannot send packet now");
5318         return ERROR_CODE_COMMAND_DISALLOWED;
5319     }
5320 
5321     // for HCI INITIALIZATION
5322     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5323     hci_stack->last_cmd_opcode = cmd->opcode;
5324 
5325     hci_reserve_packet_buffer();
5326     uint8_t * packet = hci_stack->hci_packet_buffer;
5327     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5328     uint8_t status = hci_send_cmd_packet(packet, size);
5329 
5330     // release packet buffer on error or for synchronous transport implementations
5331     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5332         hci_release_packet_buffer();
5333         hci_emit_transport_packet_sent();
5334     }
5335 
5336     return status;
5337 }
5338 
5339 /**
5340  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5341  */
5342 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5343     va_list argptr;
5344     va_start(argptr, cmd);
5345     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5346     va_end(argptr);
5347     return status;
5348 }
5349 
5350 // Create various non-HCI events.
5351 // TODO: generalize, use table similar to hci_create_command
5352 
5353 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5354     // dump packet
5355     if (dump) {
5356         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5357     }
5358 
5359     // dispatch to all event handlers
5360     btstack_linked_list_iterator_t it;
5361     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5362     while (btstack_linked_list_iterator_has_next(&it)){
5363         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5364         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5365     }
5366 }
5367 
5368 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5369     if (!hci_stack->acl_packet_handler) return;
5370     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5371 }
5372 
5373 #ifdef ENABLE_CLASSIC
5374 static void hci_notify_if_sco_can_send_now(void){
5375     // notify SCO sender if waiting
5376     if (!hci_stack->sco_waiting_for_can_send_now) return;
5377     if (hci_can_send_sco_packet_now()){
5378         hci_stack->sco_waiting_for_can_send_now = 0;
5379         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5380         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5381         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5382     }
5383 }
5384 
5385 // parsing end emitting has been merged to reduce code size
5386 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5387     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5388 
5389     uint8_t * eir_data;
5390     ad_context_t context;
5391     const uint8_t * name;
5392     uint8_t         name_len;
5393 
5394     if (size < 3) return;
5395 
5396     int event_type = hci_event_packet_get_type(packet);
5397     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5398     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5399 
5400     switch (event_type){
5401         case HCI_EVENT_INQUIRY_RESULT:
5402         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5403             if (size != (3 + (num_responses * 14))) return;
5404             break;
5405         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5406             if (size != 257) return;
5407             if (num_responses != 1) return;
5408             break;
5409         default:
5410             return;
5411     }
5412 
5413     // event[1] is set at the end
5414     int i;
5415     for (i=0; i<num_responses;i++){
5416         memset(event, 0, sizeof(event));
5417         event[0] = GAP_EVENT_INQUIRY_RESULT;
5418         uint8_t event_size = 27;    // if name is not set by EIR
5419 
5420         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5421         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5422         (void)memcpy(&event[9],
5423                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5424                      3); // class of device
5425         (void)memcpy(&event[12],
5426                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5427                      2); // clock offset
5428 
5429         switch (event_type){
5430             case HCI_EVENT_INQUIRY_RESULT:
5431                 // 14,15,16,17 = 0, size 18
5432                 break;
5433             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5434                 event[14] = 1;
5435                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5436                 // 16,17 = 0, size 18
5437                 break;
5438             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5439                 event[14] = 1;
5440                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5441                 // EIR packets only contain a single inquiry response
5442                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5443                 name = NULL;
5444                 // Iterate over EIR data
5445                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5446                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5447                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5448                     const uint8_t * data = ad_iterator_get_data(&context);
5449                     // Prefer Complete Local Name over Shortened Local Name
5450                     switch (data_type){
5451                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5452                             if (name) continue;
5453                             /* fall through */
5454                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5455                             name = data;
5456                             name_len = data_size;
5457                             break;
5458                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5459                             if (data_size != 8) break;
5460                             event[16] = 1;
5461                             memcpy(&event[17], data, 8);
5462                             break;
5463                         default:
5464                             break;
5465                     }
5466                 }
5467                 if (name){
5468                     event[25] = 1;
5469                     // truncate name if needed
5470                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5471                     event[26] = len;
5472                     (void)memcpy(&event[27], name, len);
5473                     event_size += len;
5474                 }
5475                 break;
5476             default:
5477                 return;
5478         }
5479         event[1] = event_size - 2;
5480         hci_emit_event(event, event_size, 1);
5481     }
5482 }
5483 #endif
5484 
5485 void hci_emit_state(void){
5486     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5487     uint8_t event[3];
5488     event[0] = BTSTACK_EVENT_STATE;
5489     event[1] = sizeof(event) - 2u;
5490     event[2] = hci_stack->state;
5491     hci_emit_event(event, sizeof(event), 1);
5492 }
5493 
5494 #ifdef ENABLE_CLASSIC
5495 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5496     uint8_t event[13];
5497     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5498     event[1] = sizeof(event) - 2;
5499     event[2] = status;
5500     little_endian_store_16(event, 3, con_handle);
5501     reverse_bd_addr(address, &event[5]);
5502     event[11] = 1; // ACL connection
5503     event[12] = 0; // encryption disabled
5504     hci_emit_event(event, sizeof(event), 1);
5505 }
5506 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5507     if (disable_l2cap_timeouts) return;
5508     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5509     uint8_t event[4];
5510     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5511     event[1] = sizeof(event) - 2;
5512     little_endian_store_16(event, 2, conn->con_handle);
5513     hci_emit_event(event, sizeof(event), 1);
5514 }
5515 #endif
5516 
5517 #ifdef ENABLE_BLE
5518 #ifdef ENABLE_LE_CENTRAL
5519 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){
5520     uint8_t event[21];
5521     event[0] = HCI_EVENT_LE_META;
5522     event[1] = sizeof(event) - 2u;
5523     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5524     event[3] = status;
5525     little_endian_store_16(event, 4, con_handle);
5526     event[6] = 0; // TODO: role
5527     event[7] = address_type;
5528     reverse_bd_addr(address, &event[8]);
5529     little_endian_store_16(event, 14, 0); // interval
5530     little_endian_store_16(event, 16, 0); // latency
5531     little_endian_store_16(event, 18, 0); // supervision timeout
5532     event[20] = 0; // master clock accuracy
5533     hci_emit_event(event, sizeof(event), 1);
5534 }
5535 #endif
5536 #endif
5537 
5538 static void hci_emit_transport_packet_sent(void){
5539     // notify upper stack that it might be possible to send again
5540     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5541     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5542 }
5543 
5544 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5545     uint8_t event[6];
5546     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5547     event[1] = sizeof(event) - 2u;
5548     event[2] = 0; // status = OK
5549     little_endian_store_16(event, 3, con_handle);
5550     event[5] = reason;
5551     hci_emit_event(event, sizeof(event), 1);
5552 }
5553 
5554 static void hci_emit_nr_connections_changed(void){
5555     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5556     uint8_t event[3];
5557     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5558     event[1] = sizeof(event) - 2u;
5559     event[2] = nr_hci_connections();
5560     hci_emit_event(event, sizeof(event), 1);
5561 }
5562 
5563 static void hci_emit_hci_open_failed(void){
5564     log_info("BTSTACK_EVENT_POWERON_FAILED");
5565     uint8_t event[2];
5566     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5567     event[1] = sizeof(event) - 2u;
5568     hci_emit_event(event, sizeof(event), 1);
5569 }
5570 
5571 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5572     log_info("hci_emit_dedicated_bonding_result %u ", status);
5573     uint8_t event[9];
5574     int pos = 0;
5575     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5576     event[pos++] = sizeof(event) - 2u;
5577     event[pos++] = status;
5578     reverse_bd_addr(address, &event[pos]);
5579     hci_emit_event(event, sizeof(event), 1);
5580 }
5581 
5582 
5583 #ifdef ENABLE_CLASSIC
5584 
5585 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5586     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5587     uint8_t event[5];
5588     int pos = 0;
5589     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5590     event[pos++] = sizeof(event) - 2;
5591     little_endian_store_16(event, 2, con_handle);
5592     pos += 2;
5593     event[pos++] = level;
5594     hci_emit_event(event, sizeof(event), 1);
5595 }
5596 
5597 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5598     if (!connection) return LEVEL_0;
5599     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5600     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5601     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5602     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5603     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5604     // LEVEL 4 always requires 128 bit encrytion key size
5605     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5606         security_level = LEVEL_3;
5607     }
5608     return security_level;
5609 }
5610 
5611 static void hci_emit_discoverable_enabled(uint8_t enabled){
5612     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5613     uint8_t event[3];
5614     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5615     event[1] = sizeof(event) - 2;
5616     event[2] = enabled;
5617     hci_emit_event(event, sizeof(event), 1);
5618 }
5619 
5620 // query if remote side supports eSCO
5621 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5622     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5623     if (!connection) return false;
5624     return (connection->remote_supported_features[0] & 1) != 0;
5625 }
5626 
5627 static bool hci_ssp_supported(hci_connection_t * connection){
5628     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5629     return (connection->bonding_flags & mask) == mask;
5630 }
5631 
5632 // query if remote side supports SSP
5633 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5634     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5635     if (!connection) return false;
5636     return hci_ssp_supported(connection) ? 1 : 0;
5637 }
5638 
5639 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5640     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5641 }
5642 
5643 /**
5644  * Check if remote supported features query has completed
5645  */
5646 bool hci_remote_features_available(hci_con_handle_t handle){
5647     hci_connection_t * connection = hci_connection_for_handle(handle);
5648     if (!connection) return false;
5649     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5650 }
5651 
5652 /**
5653  * Trigger remote supported features query
5654  */
5655 
5656 static void hci_trigger_remote_features_for_connection(hci_connection_t * connection){
5657     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) == 0){
5658         connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5659     }
5660 }
5661 
5662 void hci_remote_features_query(hci_con_handle_t con_handle){
5663     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5664     if (!connection) return;
5665     hci_trigger_remote_features_for_connection(connection);
5666     hci_run();
5667 }
5668 
5669 // GAP API
5670 /**
5671  * @bbrief enable/disable bonding. default is enabled
5672  * @praram enabled
5673  */
5674 void gap_set_bondable_mode(int enable){
5675     hci_stack->bondable = enable ? 1 : 0;
5676 }
5677 /**
5678  * @brief Get bondable mode.
5679  * @return 1 if bondable
5680  */
5681 int gap_get_bondable_mode(void){
5682     return hci_stack->bondable;
5683 }
5684 
5685 /**
5686  * @brief map link keys to security levels
5687  */
5688 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5689     switch (link_key_type){
5690         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5691             return LEVEL_4;
5692         case COMBINATION_KEY:
5693         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5694             return LEVEL_3;
5695         default:
5696             return LEVEL_2;
5697     }
5698 }
5699 
5700 /**
5701  * @brief map link keys to secure connection yes/no
5702  */
5703 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5704     switch (link_key_type){
5705         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5706         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5707             return 1;
5708         default:
5709             return 0;
5710     }
5711 }
5712 
5713 /**
5714  * @brief map link keys to authenticated
5715  */
5716 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5717     switch (link_key_type){
5718         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5719         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5720             return 1;
5721         default:
5722             return 0;
5723     }
5724 }
5725 
5726 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5727     log_info("gap_mitm_protection_required_for_security_level %u", level);
5728     return level > LEVEL_2;
5729 }
5730 
5731 /**
5732  * @brief get current security level
5733  */
5734 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5735     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5736     if (!connection) return LEVEL_0;
5737     return gap_security_level_for_connection(connection);
5738 }
5739 
5740 /**
5741  * @brief request connection to device to
5742  * @result GAP_AUTHENTICATION_RESULT
5743  */
5744 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5745     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5746     if (!connection){
5747         hci_emit_security_level(con_handle, LEVEL_0);
5748         return;
5749     }
5750 
5751     btstack_assert(hci_is_le_connection(connection) == false);
5752 
5753     // 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)
5754     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5755     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5756         requested_level = LEVEL_4;
5757     }
5758 
5759     gap_security_level_t current_level = gap_security_level(con_handle);
5760     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5761         requested_level, connection->requested_security_level, current_level);
5762 
5763     // authentication active if authentication request was sent or planned level > 0
5764     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5765     if (authentication_active){
5766         // authentication already active
5767         if (connection->requested_security_level < requested_level){
5768             // increase requested level as new level is higher
5769             // TODO: handle re-authentication when done
5770             connection->requested_security_level = requested_level;
5771         }
5772     } else {
5773         // no request active, notify if security sufficient
5774         if (requested_level <= current_level){
5775             hci_emit_security_level(con_handle, current_level);
5776             return;
5777         }
5778 
5779         // store request
5780         connection->requested_security_level = requested_level;
5781 
5782         // request remote features if not already active
5783         hci_remote_features_query(con_handle);
5784 
5785         // start to authenticate connection
5786         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5787         hci_run();
5788     }
5789 }
5790 
5791 /**
5792  * @brief start dedicated bonding with device. disconnect after bonding
5793  * @param device
5794  * @param request MITM protection
5795  * @result GAP_DEDICATED_BONDING_COMPLETE
5796  */
5797 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5798 
5799     // create connection state machine
5800     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5801 
5802     if (!connection){
5803         return BTSTACK_MEMORY_ALLOC_FAILED;
5804     }
5805 
5806     // delete linkn key
5807     gap_drop_link_key_for_bd_addr(device);
5808 
5809     // configure LEVEL_2/3, dedicated bonding
5810     connection->state = SEND_CREATE_CONNECTION;
5811     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5812     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5813     connection->bonding_flags = BONDING_DEDICATED;
5814 
5815     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5816 
5817     // handle: connnection failure (connection complete != ok)
5818     // handle: authentication failure
5819     // handle: disconnect on done
5820 
5821     hci_run();
5822 
5823     return 0;
5824 }
5825 
5826 void gap_set_local_name(const char * local_name){
5827     hci_stack->local_name = local_name;
5828     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5829     // also update EIR if not set by user
5830     if (hci_stack->eir_data == NULL){
5831         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5832     }
5833     hci_run();
5834 }
5835 #endif
5836 
5837 
5838 #ifdef ENABLE_BLE
5839 
5840 #ifdef ENABLE_LE_CENTRAL
5841 void gap_start_scan(void){
5842     hci_stack->le_scanning_enabled = true;
5843     hci_run();
5844 }
5845 
5846 void gap_stop_scan(void){
5847     hci_stack->le_scanning_enabled = false;
5848     hci_run();
5849 }
5850 
5851 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5852     hci_stack->le_scan_type          = scan_type;
5853     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5854     hci_stack->le_scan_interval      = scan_interval;
5855     hci_stack->le_scan_window        = scan_window;
5856     hci_stack->le_scanning_param_update = true;
5857     hci_run();
5858 }
5859 
5860 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5861     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5862 }
5863 
5864 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5865     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5866     if (!conn){
5867         // disallow if le connection is already outgoing
5868         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5869             log_error("le connection already active");
5870             return ERROR_CODE_COMMAND_DISALLOWED;
5871         }
5872 
5873         log_info("gap_connect: no connection exists yet, creating context");
5874         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5875         if (!conn){
5876             // notify client that alloc failed
5877             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5878             log_info("gap_connect: failed to alloc hci_connection_t");
5879             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5880         }
5881 
5882         // set le connecting state
5883         if (hci_is_le_connection_type(addr_type)){
5884             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5885         }
5886 
5887         conn->state = SEND_CREATE_CONNECTION;
5888         log_info("gap_connect: send create connection next");
5889         hci_run();
5890         return ERROR_CODE_SUCCESS;
5891     }
5892 
5893     if (!hci_is_le_connection(conn) ||
5894         (conn->state == SEND_CREATE_CONNECTION) ||
5895         (conn->state == SENT_CREATE_CONNECTION)) {
5896         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5897         log_error("gap_connect: classic connection or connect is already being created");
5898         return GATT_CLIENT_IN_WRONG_STATE;
5899     }
5900 
5901     // check if connection was just disconnected
5902     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5903         log_info("gap_connect: send create connection (again)");
5904         conn->state = SEND_CREATE_CONNECTION;
5905         hci_run();
5906         return ERROR_CODE_SUCCESS;
5907     }
5908 
5909     log_info("gap_connect: context exists with state %u", conn->state);
5910     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5911     hci_run();
5912     return ERROR_CODE_SUCCESS;
5913 }
5914 
5915 // @assumption: only a single outgoing LE Connection exists
5916 static hci_connection_t * gap_get_outgoing_connection(void){
5917     btstack_linked_item_t *it;
5918     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5919         hci_connection_t * conn = (hci_connection_t *) it;
5920         if (!hci_is_le_connection(conn)) continue;
5921         switch (conn->state){
5922             case SEND_CREATE_CONNECTION:
5923             case SENT_CREATE_CONNECTION:
5924             case SENT_CANCEL_CONNECTION:
5925                 return conn;
5926             default:
5927                 break;
5928         };
5929     }
5930     return NULL;
5931 }
5932 
5933 uint8_t gap_connect_cancel(void){
5934     hci_connection_t * conn = gap_get_outgoing_connection();
5935     if (!conn) return 0;
5936     switch (conn->state){
5937         case SEND_CREATE_CONNECTION:
5938             // skip sending create connection and emit event instead
5939             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5940             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5941             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5942             btstack_memory_hci_connection_free( conn );
5943             break;
5944         case SENT_CREATE_CONNECTION:
5945             // request to send cancel connection
5946             conn->state = SEND_CANCEL_CONNECTION;
5947             hci_run();
5948             break;
5949         default:
5950             break;
5951     }
5952     return 0;
5953 }
5954 #endif
5955 
5956 #ifdef ENABLE_LE_CENTRAL
5957 /**
5958  * @brief Set connection parameters for outgoing connections
5959  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5960  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5961  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5962  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5963  * @param conn_latency, default: 4
5964  * @param supervision_timeout (unit: 10ms), default: 720 ms
5965  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5966  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5967  */
5968 
5969 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5970     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5971     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5972     hci_stack->le_connection_scan_interval = conn_scan_interval;
5973     hci_stack->le_connection_scan_window = conn_scan_window;
5974     hci_stack->le_connection_interval_min = conn_interval_min;
5975     hci_stack->le_connection_interval_max = conn_interval_max;
5976     hci_stack->le_connection_latency = conn_latency;
5977     hci_stack->le_supervision_timeout = supervision_timeout;
5978     hci_stack->le_minimum_ce_length = min_ce_length;
5979     hci_stack->le_maximum_ce_length = max_ce_length;
5980 }
5981 #endif
5982 
5983 /**
5984  * @brief Updates the connection parameters for a given LE connection
5985  * @param handle
5986  * @param conn_interval_min (unit: 1.25ms)
5987  * @param conn_interval_max (unit: 1.25ms)
5988  * @param conn_latency
5989  * @param supervision_timeout (unit: 10ms)
5990  * @return 0 if ok
5991  */
5992 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5993     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5994     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5995     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5996     connection->le_conn_interval_min = conn_interval_min;
5997     connection->le_conn_interval_max = conn_interval_max;
5998     connection->le_conn_latency = conn_latency;
5999     connection->le_supervision_timeout = supervision_timeout;
6000     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
6001     hci_run();
6002     return 0;
6003 }
6004 
6005 /**
6006  * @brief Request an update of the connection parameter for a given LE connection
6007  * @param handle
6008  * @param conn_interval_min (unit: 1.25ms)
6009  * @param conn_interval_max (unit: 1.25ms)
6010  * @param conn_latency
6011  * @param supervision_timeout (unit: 10ms)
6012  * @return 0 if ok
6013  */
6014 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
6015     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
6016     hci_connection_t * connection = hci_connection_for_handle(con_handle);
6017     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6018     connection->le_conn_interval_min = conn_interval_min;
6019     connection->le_conn_interval_max = conn_interval_max;
6020     connection->le_conn_latency = conn_latency;
6021     connection->le_supervision_timeout = supervision_timeout;
6022     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
6023     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
6024     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
6025     return 0;
6026 }
6027 
6028 #ifdef ENABLE_LE_PERIPHERAL
6029 
6030 /**
6031  * @brief Set Advertisement Data
6032  * @param advertising_data_length
6033  * @param advertising_data (max 31 octets)
6034  * @note data is not copied, pointer has to stay valid
6035  */
6036 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6037     hci_stack->le_advertisements_data_len = advertising_data_length;
6038     hci_stack->le_advertisements_data = advertising_data;
6039     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6040     hci_run();
6041 }
6042 
6043 /**
6044  * @brief Set Scan Response Data
6045  * @param advertising_data_length
6046  * @param advertising_data (max 31 octets)
6047  * @note data is not copied, pointer has to stay valid
6048  */
6049 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6050     hci_stack->le_scan_response_data_len = scan_response_data_length;
6051     hci_stack->le_scan_response_data = scan_response_data;
6052     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6053     hci_run();
6054 }
6055 
6056 /**
6057  * @brief Set Advertisement Parameters
6058  * @param adv_int_min
6059  * @param adv_int_max
6060  * @param adv_type
6061  * @param direct_address_type
6062  * @param direct_address
6063  * @param channel_map
6064  * @param filter_policy
6065  *
6066  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6067  */
6068  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6069     uint8_t direct_address_typ, bd_addr_t direct_address,
6070     uint8_t channel_map, uint8_t filter_policy) {
6071 
6072     hci_stack->le_advertisements_interval_min = adv_int_min;
6073     hci_stack->le_advertisements_interval_max = adv_int_max;
6074     hci_stack->le_advertisements_type = adv_type;
6075     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6076     hci_stack->le_advertisements_channel_map = channel_map;
6077     hci_stack->le_advertisements_filter_policy = filter_policy;
6078     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6079                  6);
6080 
6081     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6082     hci_run();
6083  }
6084 
6085 /**
6086  * @brief Enable/Disable Advertisements
6087  * @param enabled
6088  */
6089 void gap_advertisements_enable(int enabled){
6090     hci_stack->le_advertisements_enabled = enabled != 0;
6091     hci_update_advertisements_enabled_for_current_roles();
6092     hci_run();
6093 }
6094 
6095 #endif
6096 
6097 void hci_le_set_own_address_type(uint8_t own_address_type){
6098     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6099     if (own_address_type == hci_stack->le_own_addr_type) return;
6100     hci_stack->le_own_addr_type = own_address_type;
6101 
6102 #ifdef ENABLE_LE_PERIPHERAL
6103     // update advertisement parameters, too
6104     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6105     hci_run();
6106 #endif
6107 #ifdef ENABLE_LE_CENTRAL
6108     // note: we don't update scan parameters or modify ongoing connection attempts
6109 #endif
6110 }
6111 
6112 void hci_le_random_address_set(const bd_addr_t random_address){
6113     memcpy(hci_stack->le_random_address, random_address, 6);
6114     hci_stack->le_random_address_set = true;
6115     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6116     hci_run();
6117 }
6118 
6119 #endif
6120 
6121 uint8_t gap_disconnect(hci_con_handle_t handle){
6122     hci_connection_t * conn = hci_connection_for_handle(handle);
6123     if (!conn){
6124         hci_emit_disconnection_complete(handle, 0);
6125         return 0;
6126     }
6127     // ignore if already disconnected
6128     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6129         return 0;
6130     }
6131     conn->state = SEND_DISCONNECT;
6132     hci_run();
6133     return 0;
6134 }
6135 
6136 int gap_read_rssi(hci_con_handle_t con_handle){
6137     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6138     if (hci_connection == NULL) return 0;
6139     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6140     hci_run();
6141     return 1;
6142 }
6143 
6144 /**
6145  * @brief Get connection type
6146  * @param con_handle
6147  * @result connection_type
6148  */
6149 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6150     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6151     if (!conn) return GAP_CONNECTION_INVALID;
6152     switch (conn->address_type){
6153         case BD_ADDR_TYPE_LE_PUBLIC:
6154         case BD_ADDR_TYPE_LE_RANDOM:
6155             return GAP_CONNECTION_LE;
6156         case BD_ADDR_TYPE_SCO:
6157             return GAP_CONNECTION_SCO;
6158         case BD_ADDR_TYPE_ACL:
6159             return GAP_CONNECTION_ACL;
6160         default:
6161             return GAP_CONNECTION_INVALID;
6162     }
6163 }
6164 
6165 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6166     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6167     if (!conn) return HCI_ROLE_INVALID;
6168     return (hci_role_t) conn->role;
6169 }
6170 
6171 
6172 #ifdef ENABLE_CLASSIC
6173 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6174     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6175     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6176     conn->request_role = role;
6177     hci_run();
6178     return ERROR_CODE_SUCCESS;
6179 }
6180 #endif
6181 
6182 #ifdef ENABLE_BLE
6183 
6184 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){
6185     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6186     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6187 
6188     conn->le_phy_update_all_phys    = all_phys;
6189     conn->le_phy_update_tx_phys     = tx_phys;
6190     conn->le_phy_update_rx_phys     = rx_phys;
6191     conn->le_phy_update_phy_options = phy_options;
6192 
6193     hci_run();
6194 
6195     return 0;
6196 }
6197 
6198 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6199     // check if already in list
6200     btstack_linked_list_iterator_t it;
6201     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6202     while (btstack_linked_list_iterator_has_next(&it)) {
6203         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6204         if (entry->address_type != address_type) {
6205             continue;
6206         }
6207         if (memcmp(entry->address, address, 6) != 0) {
6208             continue;
6209         }
6210 		// disallow if already scheduled to add
6211 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6212 			return ERROR_CODE_COMMAND_DISALLOWED;
6213 		}
6214 		// still on controller, but scheduled to remove -> re-add
6215 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6216 		return ERROR_CODE_SUCCESS;
6217     }
6218     // alloc and add to list
6219     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6220     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6221     entry->address_type = address_type;
6222     (void)memcpy(entry->address, address, 6);
6223     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6224     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6225     return ERROR_CODE_SUCCESS;
6226 }
6227 
6228 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6229     btstack_linked_list_iterator_t it;
6230     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6231     while (btstack_linked_list_iterator_has_next(&it)){
6232         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6233         if (entry->address_type != address_type) {
6234             continue;
6235         }
6236         if (memcmp(entry->address, address, 6) != 0) {
6237             continue;
6238         }
6239         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6240             // remove from controller if already present
6241             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6242         }  else {
6243             // directly remove entry from whitelist
6244             btstack_linked_list_iterator_remove(&it);
6245             btstack_memory_whitelist_entry_free(entry);
6246         }
6247         return ERROR_CODE_SUCCESS;
6248     }
6249     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6250 }
6251 
6252 static void hci_whitelist_clear(void){
6253     btstack_linked_list_iterator_t it;
6254     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6255     while (btstack_linked_list_iterator_has_next(&it)){
6256         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6257         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6258             // remove from controller if already present
6259             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6260             continue;
6261         }
6262         // directly remove entry from whitelist
6263         btstack_linked_list_iterator_remove(&it);
6264         btstack_memory_whitelist_entry_free(entry);
6265     }
6266 }
6267 
6268 // free all entries unconditionally
6269 static void hci_whitelist_free(void){
6270     btstack_linked_list_iterator_t lit;
6271     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
6272     while (btstack_linked_list_iterator_has_next(&lit)){
6273         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
6274         btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
6275         btstack_memory_whitelist_entry_free(entry);
6276     }
6277 }
6278 
6279 /**
6280  * @brief Clear Whitelist
6281  * @return 0 if ok
6282  */
6283 uint8_t gap_whitelist_clear(void){
6284     hci_whitelist_clear();
6285     hci_run();
6286     return ERROR_CODE_SUCCESS;
6287 }
6288 
6289 /**
6290  * @brief Add Device to Whitelist
6291  * @param address_typ
6292  * @param address
6293  * @return 0 if ok
6294  */
6295 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6296     uint8_t status = hci_whitelist_add(address_type, address);
6297     if (status){
6298         return status;
6299     }
6300     hci_run();
6301     return ERROR_CODE_SUCCESS;
6302 }
6303 
6304 /**
6305  * @brief Remove Device from Whitelist
6306  * @param address_typ
6307  * @param address
6308  * @return 0 if ok
6309  */
6310 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6311     uint8_t status = hci_whitelist_remove(address_type, address);
6312     if (status){
6313         return status;
6314     }
6315     hci_run();
6316     return ERROR_CODE_SUCCESS;
6317 }
6318 
6319 #ifdef ENABLE_LE_CENTRAL
6320 /**
6321  * @brief Connect with Whitelist
6322  * @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6323  * @return - if ok
6324  */
6325 uint8_t gap_connect_with_whitelist(void){
6326     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6327         return ERROR_CODE_COMMAND_DISALLOWED;
6328     }
6329     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6330     hci_run();
6331     return ERROR_CODE_SUCCESS;
6332 }
6333 
6334 /**
6335  * @brief Auto Connection Establishment - Start Connecting to device
6336  * @param address_typ
6337  * @param address
6338  * @return 0 if ok
6339  */
6340 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6341     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6342         return ERROR_CODE_COMMAND_DISALLOWED;
6343     }
6344 
6345     uint8_t status = hci_whitelist_add(address_type, address);
6346     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6347         return status;
6348     }
6349 
6350     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6351 
6352     hci_run();
6353     return ERROR_CODE_SUCCESS;
6354 }
6355 
6356 /**
6357  * @brief Auto Connection Establishment - Stop Connecting to device
6358  * @param address_typ
6359  * @param address
6360  * @return 0 if ok
6361  */
6362 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6363     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6364         return ERROR_CODE_COMMAND_DISALLOWED;
6365     }
6366 
6367     hci_whitelist_remove(address_type, address);
6368     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6369         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6370     }
6371     hci_run();
6372     return 0;
6373 }
6374 
6375 /**
6376  * @brief Auto Connection Establishment - Stop everything
6377  * @note  Convenience function to stop all active auto connection attempts
6378  */
6379 uint8_t gap_auto_connection_stop_all(void){
6380     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6381         return ERROR_CODE_COMMAND_DISALLOWED;
6382     }
6383     hci_whitelist_clear();
6384     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6385     hci_run();
6386     return ERROR_CODE_SUCCESS;
6387 }
6388 
6389 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6390     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6391     if (!conn) return 0;
6392     return conn->le_connection_interval;
6393 }
6394 #endif
6395 #endif
6396 
6397 #ifdef ENABLE_CLASSIC
6398 /**
6399  * @brief Set Extended Inquiry Response data
6400  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6401  * @note has to be done before stack starts up
6402  */
6403 void gap_set_extended_inquiry_response(const uint8_t * data){
6404     hci_stack->eir_data = data;
6405     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6406     hci_run();
6407 }
6408 
6409 /**
6410  * @brief Start GAP Classic Inquiry
6411  * @param duration in 1.28s units
6412  * @return 0 if ok
6413  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6414  */
6415 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6416     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6417     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6418     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6419         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6420     }
6421     hci_stack->inquiry_state = duration_in_1280ms_units;
6422     hci_run();
6423     return 0;
6424 }
6425 
6426 /**
6427  * @brief Stop GAP Classic Inquiry
6428  * @return 0 if ok
6429  */
6430 int gap_inquiry_stop(void){
6431     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6432         // emit inquiry complete event, before it even started
6433         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6434         hci_emit_event(event, sizeof(event), 1);
6435         return 0;
6436     }
6437     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6438     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6439     hci_run();
6440     return 0;
6441 }
6442 
6443 void gap_inquiry_set_lap(uint32_t lap){
6444     hci_stack->inquiry_lap = lap;
6445 }
6446 
6447 void gap_inquiry_set_scan_activity(uint16_t inquiry_scan_interval, uint16_t inquiry_scan_window){
6448     hci_stack->inquiry_scan_interval = inquiry_scan_interval;
6449     hci_stack->inquiry_scan_window   = inquiry_scan_window;
6450     hci_stack->gap_tasks |= GAP_TASK_WRITE_INQUIRY_SCAN_ACTIVITY;
6451     hci_run();
6452 }
6453 
6454 
6455 /**
6456  * @brief Remote Name Request
6457  * @param addr
6458  * @param page_scan_repetition_mode
6459  * @param clock_offset only used when bit 15 is set
6460  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6461  */
6462 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6463     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6464     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6465     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6466     hci_stack->remote_name_clock_offset = clock_offset;
6467     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6468     hci_run();
6469     return 0;
6470 }
6471 
6472 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6473     hci_stack->gap_pairing_state = state;
6474     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6475     hci_run();
6476     return 0;
6477 }
6478 
6479 /**
6480  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6481  * @param addr
6482  * @param pin_data
6483  * @param pin_len
6484  * @return 0 if ok
6485  */
6486 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6487     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6488     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6489     hci_stack->gap_pairing_pin_len = pin_len;
6490     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6491 }
6492 
6493 /**
6494  * @brief Legacy Pairing Pin Code Response
6495  * @param addr
6496  * @param pin
6497  * @return 0 if ok
6498  */
6499 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6500     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6501 }
6502 
6503 /**
6504  * @brief Abort Legacy Pairing
6505  * @param addr
6506  * @param pin
6507  * @return 0 if ok
6508  */
6509 int gap_pin_code_negative(bd_addr_t addr){
6510     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6511     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6512 }
6513 
6514 /**
6515  * @brief SSP Passkey Response
6516  * @param addr
6517  * @param passkey
6518  * @return 0 if ok
6519  */
6520 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6521     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6522     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6523     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6524 }
6525 
6526 /**
6527  * @brief Abort SSP Passkey Entry/Pairing
6528  * @param addr
6529  * @param pin
6530  * @return 0 if ok
6531  */
6532 int gap_ssp_passkey_negative(const bd_addr_t addr){
6533     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6534     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6535 }
6536 
6537 /**
6538  * @brief Accept SSP Numeric Comparison
6539  * @param addr
6540  * @param passkey
6541  * @return 0 if ok
6542  */
6543 int gap_ssp_confirmation_response(const bd_addr_t addr){
6544     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6545     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6546 }
6547 
6548 /**
6549  * @brief Abort SSP Numeric Comparison/Pairing
6550  * @param addr
6551  * @param pin
6552  * @return 0 if ok
6553  */
6554 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6555     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6556     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6557 }
6558 
6559 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6560 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6561     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6562     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6563     connectionSetAuthenticationFlags(conn, flag);
6564     hci_run();
6565     return ERROR_CODE_SUCCESS;
6566 }
6567 #endif
6568 
6569 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6570 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6571     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6572 }
6573 
6574 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6575     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6576 }
6577 #endif
6578 
6579 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6580 /**
6581  * @brief Report Remote OOB Data
6582  * @param bd_addr
6583  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6584  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6585  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6586  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6587  */
6588 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){
6589     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6590     if (connection == NULL) {
6591         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6592     }
6593     connection->classic_oob_c_192 = c_192;
6594     connection->classic_oob_r_192 = r_192;
6595 
6596     // ignore P-256 if not supported by us
6597     if (hci_stack->secure_connections_active){
6598         connection->classic_oob_c_256 = c_256;
6599         connection->classic_oob_r_256 = r_256;
6600     }
6601 
6602     return ERROR_CODE_SUCCESS;
6603 }
6604 /**
6605  * @brief Generate new OOB data
6606  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6607  */
6608 void gap_ssp_generate_oob_data(void){
6609     hci_stack->classic_read_local_oob_data = true;
6610     hci_run();
6611 }
6612 
6613 #endif
6614 
6615 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6616 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6617     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6618     if (connection == NULL) {
6619         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6620     }
6621 
6622     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6623     connection->link_key_type = type;
6624 
6625     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6626 }
6627 
6628 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6629 /**
6630  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6631  * @param inquiry_mode see bluetooth_defines.h
6632  */
6633 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6634     hci_stack->inquiry_mode = inquiry_mode;
6635 }
6636 
6637 /**
6638  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6639  */
6640 void hci_set_sco_voice_setting(uint16_t voice_setting){
6641     hci_stack->sco_voice_setting = voice_setting;
6642 }
6643 
6644 /**
6645  * @brief Get SCO Voice Setting
6646  * @return current voice setting
6647  */
6648 uint16_t hci_get_sco_voice_setting(void){
6649     return hci_stack->sco_voice_setting;
6650 }
6651 
6652 static int hci_have_usb_transport(void){
6653     if (!hci_stack->hci_transport) return 0;
6654     const char * transport_name = hci_stack->hci_transport->name;
6655     if (!transport_name) return 0;
6656     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6657 }
6658 
6659 /** @brief Get SCO packet length for current SCO Voice setting
6660  *  @note  Using SCO packets of the exact length is required for USB transfer
6661  *  @return Length of SCO packets in bytes (not audio frames)
6662  */
6663 uint16_t hci_get_sco_packet_length(void){
6664     uint16_t sco_packet_length = 0;
6665 
6666 #ifdef ENABLE_SCO_OVER_HCI
6667     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6668     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6669 
6670     if (hci_have_usb_transport()){
6671         // see Core Spec for H2 USB Transfer.
6672         // 3 byte SCO header + 24 bytes per connection
6673         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6674         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6675     } else {
6676         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6677         sco_packet_length = 3 + 60 * multiplier;
6678         // assert that it still fits inside an SCO buffer
6679         if (sco_packet_length > hci_stack->sco_data_packet_length){
6680             sco_packet_length = 3 + 60;
6681         }
6682     }
6683 #endif
6684 
6685 #ifdef HAVE_SCO_TRANSPORT
6686     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6687     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6688     sco_packet_length = 3 + 60 * multiplier;
6689 #endif
6690     return sco_packet_length;
6691 }
6692 
6693 /**
6694 * @brief Sets the master/slave policy
6695 * @param policy (0: attempt to become master, 1: let connecting device decide)
6696 */
6697 void hci_set_master_slave_policy(uint8_t policy){
6698     hci_stack->master_slave_policy = policy;
6699 }
6700 
6701 #endif
6702 
6703 HCI_STATE hci_get_state(void){
6704     return hci_stack->state;
6705 }
6706 
6707 #ifdef ENABLE_CLASSIC
6708 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6709     hci_stack->gap_classic_accept_callback = accept_callback;
6710 }
6711 #endif
6712 
6713 /**
6714  * @brief Set callback for Bluetooth Hardware Error
6715  */
6716 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6717     hci_stack->hardware_error_callback = fn;
6718 }
6719 
6720 void hci_disconnect_all(void){
6721     btstack_linked_list_iterator_t it;
6722     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6723     while (btstack_linked_list_iterator_has_next(&it)){
6724         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6725         if (con->state == SENT_DISCONNECT) continue;
6726         con->state = SEND_DISCONNECT;
6727     }
6728     hci_run();
6729 }
6730 
6731 uint16_t hci_get_manufacturer(void){
6732     return hci_stack->manufacturer;
6733 }
6734 
6735 #ifdef ENABLE_BLE
6736 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6737     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6738     if (!hci_con) return NULL;
6739     return &hci_con->sm_connection;
6740 }
6741 
6742 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6743 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6744 #endif
6745 
6746 int gap_encryption_key_size(hci_con_handle_t con_handle){
6747     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6748     if (hci_connection == NULL) return 0;
6749     if (hci_is_le_connection(hci_connection)){
6750 #ifdef ENABLE_BLE
6751         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6752         if (sm_conn->sm_connection_encrypted) {
6753             return sm_conn->sm_actual_encryption_key_size;
6754         }
6755 #endif
6756     } else {
6757 #ifdef ENABLE_CLASSIC
6758         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6759             return hci_connection->encryption_key_size;
6760         }
6761 #endif
6762     }
6763     return 0;
6764 }
6765 
6766 int gap_authenticated(hci_con_handle_t con_handle){
6767     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6768     if (hci_connection == NULL) return 0;
6769 
6770     switch (hci_connection->address_type){
6771 #ifdef ENABLE_BLE
6772         case BD_ADDR_TYPE_LE_PUBLIC:
6773         case BD_ADDR_TYPE_LE_RANDOM:
6774             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6775             return hci_connection->sm_connection.sm_connection_authenticated;
6776 #endif
6777 #ifdef ENABLE_CLASSIC
6778         case BD_ADDR_TYPE_SCO:
6779         case BD_ADDR_TYPE_ACL:
6780             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6781 #endif
6782         default:
6783             return 0;
6784     }
6785 }
6786 
6787 int gap_secure_connection(hci_con_handle_t con_handle){
6788     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6789     if (hci_connection == NULL) return 0;
6790 
6791     switch (hci_connection->address_type){
6792 #ifdef ENABLE_BLE
6793         case BD_ADDR_TYPE_LE_PUBLIC:
6794         case BD_ADDR_TYPE_LE_RANDOM:
6795             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6796             return hci_connection->sm_connection.sm_connection_sc;
6797 #endif
6798 #ifdef ENABLE_CLASSIC
6799         case BD_ADDR_TYPE_SCO:
6800         case BD_ADDR_TYPE_ACL:
6801             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6802 #endif
6803         default:
6804             return 0;
6805     }
6806 }
6807 
6808 bool gap_bonded(hci_con_handle_t con_handle){
6809 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6810 	if (hci_connection == NULL) return 0;
6811 
6812 #ifdef ENABLE_CLASSIC
6813 	link_key_t link_key;
6814 	link_key_type_t link_key_type;
6815 #endif
6816 	switch (hci_connection->address_type){
6817 #ifdef ENABLE_BLE
6818 		case BD_ADDR_TYPE_LE_PUBLIC:
6819 		case BD_ADDR_TYPE_LE_RANDOM:
6820 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6821 #endif
6822 #ifdef ENABLE_CLASSIC
6823 		case BD_ADDR_TYPE_SCO:
6824 		case BD_ADDR_TYPE_ACL:
6825 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6826 #endif
6827 		default:
6828 			return false;
6829 	}
6830 }
6831 
6832 #ifdef ENABLE_BLE
6833 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6834     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6835     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6836     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6837     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6838     return sm_conn->sm_connection_authorization_state;
6839 }
6840 #endif
6841 
6842 #ifdef ENABLE_CLASSIC
6843 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){
6844     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6845     if (!conn) return GAP_CONNECTION_INVALID;
6846     conn->sniff_min_interval = sniff_min_interval;
6847     conn->sniff_max_interval = sniff_max_interval;
6848     conn->sniff_attempt = sniff_attempt;
6849     conn->sniff_timeout = sniff_timeout;
6850     hci_run();
6851     return 0;
6852 }
6853 
6854 /**
6855  * @brief Exit Sniff mode
6856  * @param con_handle
6857  @ @return 0 if ok
6858  */
6859 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6860     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6861     if (!conn) return GAP_CONNECTION_INVALID;
6862     conn->sniff_min_interval = 0xffff;
6863     hci_run();
6864     return 0;
6865 }
6866 
6867 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){
6868     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6869     if (!conn) return GAP_CONNECTION_INVALID;
6870     conn->sniff_subrating_max_latency = max_latency;
6871     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6872     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6873     hci_run();
6874     return ERROR_CODE_SUCCESS;
6875 }
6876 
6877 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){
6878     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6879     if (!conn) return GAP_CONNECTION_INVALID;
6880     conn->qos_service_type = service_type;
6881     conn->qos_token_rate = token_rate;
6882     conn->qos_peak_bandwidth = peak_bandwidth;
6883     conn->qos_latency = latency;
6884     conn->qos_delay_variation = delay_variation;
6885     hci_run();
6886     return ERROR_CODE_SUCCESS;
6887 }
6888 
6889 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6890     hci_stack->new_page_scan_interval = page_scan_interval;
6891     hci_stack->new_page_scan_window = page_scan_window;
6892     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6893     hci_run();
6894 }
6895 
6896 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6897     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6898     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6899     hci_run();
6900 }
6901 
6902 void gap_set_page_timeout(uint16_t page_timeout){
6903     hci_stack->page_timeout = page_timeout;
6904     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_TIMEOUT;
6905     hci_run();
6906 }
6907 
6908 #endif
6909 
6910 void hci_halting_defer(void){
6911     if (hci_stack->state != HCI_STATE_HALTING) return;
6912     switch (hci_stack->substate){
6913         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6914         case HCI_HALTING_CLOSE:
6915             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6916             break;
6917         default:
6918             break;
6919     }
6920 }
6921 
6922 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6923 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6924     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6925     if (le_device_db_index >= le_device_db_max_count()) return;
6926     uint8_t offset = le_device_db_index >> 3;
6927     uint8_t mask = 1 << (le_device_db_index & 7);
6928     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6929     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6930     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6931         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6932     }
6933 }
6934 
6935 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6936 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6937 	if (le_device_db_index >= le_device_db_max_count()) return;
6938 	uint8_t offset = le_device_db_index >> 3;
6939 	uint8_t mask = 1 << (le_device_db_index & 7);
6940 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6941 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6942 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6943 	}
6944 }
6945 
6946 uint8_t gap_load_resolving_list_from_le_device_db(void){
6947 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6948 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6949 	}
6950 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6951 		// restart le resolving list update
6952 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6953 	}
6954 	return ERROR_CODE_SUCCESS;
6955 }
6956 #endif
6957 
6958 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6959 void hci_setup_test_connections_fuzz(void){
6960     hci_connection_t * conn;
6961 
6962     // default address: 66:55:44:33:00:01
6963     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6964 
6965     // setup Controller info
6966     hci_stack->num_cmd_packets = 255;
6967     hci_stack->acl_packets_total_num = 255;
6968 
6969     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6970     addr[5] = 0x01;
6971     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6972     conn->con_handle = addr[5];
6973     conn->role  = HCI_ROLE_SLAVE;
6974     conn->state = RECEIVED_CONNECTION_REQUEST;
6975     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6976 
6977     // setup incoming Classic SCO connection with con handle 0x0002
6978     addr[5] = 0x02;
6979     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6980     conn->con_handle = addr[5];
6981     conn->role  = HCI_ROLE_SLAVE;
6982     conn->state = RECEIVED_CONNECTION_REQUEST;
6983     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6984 
6985     // setup ready Classic ACL connection with con handle 0x0003
6986     addr[5] = 0x03;
6987     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6988     conn->con_handle = addr[5];
6989     conn->role  = HCI_ROLE_SLAVE;
6990     conn->state = OPEN;
6991     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6992 
6993     // setup ready Classic SCO connection with con handle 0x0004
6994     addr[5] = 0x04;
6995     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6996     conn->con_handle = addr[5];
6997     conn->role  = HCI_ROLE_SLAVE;
6998     conn->state = OPEN;
6999     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
7000 
7001     // setup ready LE ACL connection with con handle 0x005 and public address
7002     addr[5] = 0x05;
7003     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
7004     conn->con_handle = addr[5];
7005     conn->role  = HCI_ROLE_SLAVE;
7006     conn->state = OPEN;
7007     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
7008     conn->sm_connection.sm_connection_encrypted = 1;
7009 }
7010 
7011 void hci_free_connections_fuzz(void){
7012     btstack_linked_list_iterator_t it;
7013     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
7014     while (btstack_linked_list_iterator_has_next(&it)){
7015         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
7016         btstack_linked_list_iterator_remove(&it);
7017         btstack_memory_hci_connection_free(con);
7018     }
7019 }
7020 void hci_simulate_working_fuzz(void){
7021     hci_init_done();
7022     hci_stack->num_cmd_packets = 255;
7023 }
7024 #endif
7025