xref: /btstack/src/hci.c (revision 461a2bc4b085abdabe6c7af40c278636bcefb607)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef ENABLE_BLE
57 #include "gap.h"
58 #include "ble/le_device_db.h"
59 #endif
60 
61 #include <stdarg.h>
62 #include <string.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "bluetooth_company_id.h"
70 #include "bluetooth_data_types.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 #include "ad_parser.h"
76 
77 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
78 #ifndef HCI_HOST_ACL_PACKET_NUM
79 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
80 #endif
81 #ifndef HCI_HOST_ACL_PACKET_LEN
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
83 #endif
84 #ifndef HCI_HOST_SCO_PACKET_NUM
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_LEN
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
89 #endif
90 #endif
91 
92 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
93 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
98 #endif
99 
100 #define HCI_CONNECTION_TIMEOUT_MS 10000
101 
102 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
103 #define HCI_RESET_RESEND_TIMEOUT_MS 200
104 #endif
105 
106 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
107 #ifndef GAP_INQUIRY_MAX_NAME_LEN
108 #define GAP_INQUIRY_MAX_NAME_LEN 32
109 #endif
110 
111 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
112 #define GAP_INQUIRY_DURATION_MIN       0x01
113 #define GAP_INQUIRY_DURATION_MAX       0x30
114 #define GAP_INQUIRY_STATE_IDLE         0x00
115 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
116 #define GAP_INQUIRY_STATE_ACTIVE       0x81
117 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
118 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
119 
120 // GAP Remote Name Request
121 #define GAP_REMOTE_NAME_STATE_IDLE 0
122 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
123 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
124 
125 // GAP Pairing
126 #define GAP_PAIRING_STATE_IDLE                       0
127 #define GAP_PAIRING_STATE_SEND_PIN                   1
128 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
129 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
130 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
131 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
132 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
133 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
134 
135 // prototypes
136 #ifdef ENABLE_CLASSIC
137 static void hci_update_scan_enable(void);
138 static void hci_emit_discoverable_enabled(uint8_t enabled);
139 static int  hci_local_ssp_activated(void);
140 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
141 static bool hci_ssp_supported(hci_connection_t * connection);
142 static void hci_notify_if_sco_can_send_now(void);
143 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
144 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
145 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
146 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
147 static void hci_connection_timestamp(hci_connection_t *connection);
148 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
149 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
150 #endif
151 
152 static int  hci_power_control_on(void);
153 static void hci_power_control_off(void);
154 static void hci_state_reset(void);
155 static void hci_emit_transport_packet_sent(void);
156 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
157 static void hci_emit_nr_connections_changed(void);
158 static void hci_emit_hci_open_failed(void);
159 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
160 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
161 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
162 static void hci_run(void);
163 static int  hci_is_le_connection(hci_connection_t * connection);
164 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 #endif
169 
170 #ifdef ENABLE_BLE
171 #ifdef ENABLE_LE_CENTRAL
172 // called from test/ble_client/advertising_data_parser.c
173 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
174 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
175 static hci_connection_t * gap_get_outgoing_connection(void);
176 #endif
177 #endif
178 
179 // the STACK is here
180 #ifndef HAVE_MALLOC
181 static hci_stack_t   hci_stack_static;
182 #endif
183 static hci_stack_t * hci_stack = NULL;
184 
185 #ifdef ENABLE_CLASSIC
186 // default name
187 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
188 
189 // test helper
190 static uint8_t disable_l2cap_timeouts = 0;
191 #endif
192 
193 // reset connection state on create and on reconnect
194 // don't overwrite addr, con handle, role
195 static void hci_connection_init(hci_connection_t * conn){
196     conn->authentication_flags = AUTH_FLAG_NONE;
197     conn->bonding_flags = 0;
198     conn->requested_security_level = LEVEL_0;
199 #ifdef ENABLE_CLASSIC
200     conn->request_role = HCI_ROLE_INVALID;
201     conn->sniff_subrating_max_latency = 0xffff;
202     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
203     conn->link_key_type = INVALID_LINK_KEY;
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219 #ifdef ENABLE_CLASSIC_PAIRING_OOB
220     conn->classic_oob_c_192 = NULL;
221     conn->classic_oob_r_192 = NULL;
222     conn->classic_oob_c_256 = NULL;
223     conn->classic_oob_r_256 = NULL;
224 #endif
225 }
226 
227 /**
228  * create connection for given address
229  *
230  * @return connection OR NULL, if no memory left
231  */
232 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
233     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
234 
235     hci_connection_t * conn = btstack_memory_hci_connection_get();
236     if (!conn) return NULL;
237     hci_connection_init(conn);
238 
239     bd_addr_copy(conn->address, addr);
240     conn->address_type = addr_type;
241     conn->con_handle = HCI_CON_HANDLE_INVALID;
242     conn->role = HCI_ROLE_INVALID;
243 
244     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
245 
246     return conn;
247 }
248 
249 
250 /**
251  * get le connection parameter range
252 *
253  * @return le connection parameter range struct
254  */
255 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
256     *range = hci_stack->le_connection_parameter_range;
257 }
258 
259 /**
260  * set le connection parameter range
261  *
262  */
263 
264 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
265     hci_stack->le_connection_parameter_range = *range;
266 }
267 
268 /**
269  * @brief Test if connection parameters are inside in existing rage
270  * @param conn_interval_min (unit: 1.25ms)
271  * @param conn_interval_max (unit: 1.25ms)
272  * @param conn_latency
273  * @param supervision_timeout (unit: 10ms)
274  * @returns 1 if included
275  */
276 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
277     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
278     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
279 
280     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
281     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
282 
283     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
284     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
285 
286     return 1;
287 }
288 
289 /**
290  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
291  * @note: default: 1
292  * @param max_peripheral_connections
293  */
294 #ifdef ENABLE_LE_PERIPHERAL
295 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
296     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
297 }
298 #endif
299 
300 /**
301  * get hci connections iterator
302  *
303  * @return hci connections iterator
304  */
305 
306 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
307     btstack_linked_list_iterator_init(it, &hci_stack->connections);
308 }
309 
310 /**
311  * get connection for a given handle
312  *
313  * @return connection OR NULL, if not found
314  */
315 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
316     btstack_linked_list_iterator_t it;
317     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
318     while (btstack_linked_list_iterator_has_next(&it)){
319         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
320         if ( item->con_handle == con_handle ) {
321             return item;
322         }
323     }
324     return NULL;
325 }
326 
327 /**
328  * get connection for given address
329  *
330  * @return connection OR NULL, if not found
331  */
332 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != addr_type)  continue;
338         if (memcmp(addr, connection->address, 6) != 0) continue;
339         return connection;
340     }
341     return NULL;
342 }
343 
344 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
345     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
346 }
347 
348 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
349     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
350 }
351 
352 #ifdef ENABLE_CLASSIC
353 
354 #ifdef ENABLE_SCO_OVER_HCI
355 static int hci_number_sco_connections(void){
356     int connections = 0;
357     btstack_linked_list_iterator_t it;
358     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
359     while (btstack_linked_list_iterator_has_next(&it)){
360         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
361         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
362         connections++;
363     }
364     return connections;
365 }
366 #endif
367 
368 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
369     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
370 #ifdef HAVE_EMBEDDED_TICK
371     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
372         // connections might be timed out
373         hci_emit_l2cap_check_timeout(connection);
374     }
375 #else
376     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
377         // connections might be timed out
378         hci_emit_l2cap_check_timeout(connection);
379     }
380 #endif
381 }
382 
383 static void hci_connection_timestamp(hci_connection_t *connection){
384 #ifdef HAVE_EMBEDDED_TICK
385     connection->timestamp = btstack_run_loop_embedded_get_ticks();
386 #else
387     connection->timestamp = btstack_run_loop_get_time_ms();
388 #endif
389 }
390 
391 /**
392  * add authentication flags and reset timer
393  * @note: assumes classic connection
394  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
395  */
396 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
397     bd_addr_t addr;
398     reverse_bd_addr(bd_addr, addr);
399     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
400     if (conn) {
401         connectionSetAuthenticationFlags(conn, flags);
402         hci_connection_timestamp(conn);
403     }
404 }
405 
406 static bool hci_pairing_active(hci_connection_t * hci_connection){
407     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
408 }
409 
410 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
411     if (hci_pairing_active(hci_connection)) return;
412     if (ssp){
413         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
414     } else {
415         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
416     }
417     // if we are initiator, we have sent an HCI Authenticate Request
418     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
419 
420     // if we are responder, use minimal service security level as required level
421     if (!initiator){
422         hci_connection->requested_security_level = (gap_security_level_t) btstack_max((uint32_t) hci_connection->requested_security_level, (uint32_t) hci_stack->gap_minimal_service_security_level);
423     }
424 
425     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
426 
427     uint8_t event[12];
428     event[0] = GAP_EVENT_PAIRING_STARTED;
429     event[1] = 10;
430     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
431     reverse_bd_addr(hci_connection->address, &event[4]);
432     event[10] = (uint8_t) ssp;
433     event[11] = (uint8_t) initiator;
434     hci_emit_event(event, sizeof(event), 1);
435 }
436 
437 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
438     hci_connection->requested_security_level = LEVEL_0;
439     if (!hci_pairing_active(hci_connection)) return;
440     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
441 #ifdef ENABLE_CLASSIC_PAIRING_OOB
442     hci_connection->classic_oob_c_192 = NULL;
443     hci_connection->classic_oob_r_192 = NULL;
444     hci_connection->classic_oob_c_256 = NULL;
445     hci_connection->classic_oob_r_256 = NULL;
446 #endif
447     log_info("pairing complete, status %02x", status);
448 
449     uint8_t event[12];
450     event[0] = GAP_EVENT_PAIRING_COMPLETE;
451     event[1] = 9;
452     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
453     reverse_bd_addr(hci_connection->address, &event[4]);
454     event[10] = status;
455     hci_emit_event(event, sizeof(event), 1);
456 }
457 
458 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
459     hci_connection_t * conn = hci_connection_for_handle(handle);
460     if (!conn) return false;
461     return hci_pairing_active(conn);
462 }
463 
464 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
465     if (!hci_stack->link_key_db) return;
466     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
467     hci_stack->link_key_db->delete_link_key(addr);
468 }
469 
470 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
471     if (!hci_stack->link_key_db) return;
472     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
473     hci_stack->link_key_db->put_link_key(addr, link_key, type);
474 }
475 
476 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
477 	if (!hci_stack->link_key_db) return false;
478 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
479 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
480 	return result;
481 }
482 
483 void gap_delete_all_link_keys(void){
484     bd_addr_t  addr;
485     link_key_t link_key;
486     link_key_type_t type;
487     btstack_link_key_iterator_t it;
488     int ok = gap_link_key_iterator_init(&it);
489     if (!ok) {
490         log_error("could not initialize iterator");
491         return;
492     }
493     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
494         gap_drop_link_key_for_bd_addr(addr);
495     }
496     gap_link_key_iterator_done(&it);
497 }
498 
499 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
500     if (!hci_stack->link_key_db) return 0;
501     if (!hci_stack->link_key_db->iterator_init) return 0;
502     return hci_stack->link_key_db->iterator_init(it);
503 }
504 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
505     if (!hci_stack->link_key_db) return 0;
506     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
507 }
508 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
509     if (!hci_stack->link_key_db) return;
510     hci_stack->link_key_db->iterator_done(it);
511 }
512 #endif
513 
514 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
515     switch (address_type){
516         case BD_ADDR_TYPE_LE_PUBLIC:
517         case BD_ADDR_TYPE_LE_RANDOM:
518         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
519         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
520             return true;
521         default:
522             return false;
523     }
524 }
525 
526 static int hci_is_le_connection(hci_connection_t * connection){
527     return hci_is_le_connection_type(connection->address_type);
528 }
529 
530 /**
531  * count connections
532  */
533 static int nr_hci_connections(void){
534     int count = 0;
535     btstack_linked_item_t *it;
536     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
537         count++;
538     }
539     return count;
540 }
541 
542 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
543 
544     unsigned int num_packets_sent_classic = 0;
545     unsigned int num_packets_sent_le = 0;
546 
547     btstack_linked_item_t *it;
548     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
549         hci_connection_t * connection = (hci_connection_t *) it;
550         if (hci_is_le_connection(connection)){
551             num_packets_sent_le += connection->num_packets_sent;
552         }
553         if (connection->address_type == BD_ADDR_TYPE_ACL){
554             num_packets_sent_classic += connection->num_packets_sent;
555         }
556     }
557     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
558     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
559     int free_slots_le = 0;
560 
561     if (free_slots_classic < 0){
562         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
563         return 0;
564     }
565 
566     if (hci_stack->le_acl_packets_total_num){
567         // if we have LE slots, they are used
568         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
569         if (free_slots_le < 0){
570             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
571             return 0;
572         }
573     } else {
574         // otherwise, classic slots are used for LE, too
575         free_slots_classic -= num_packets_sent_le;
576         if (free_slots_classic < 0){
577             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
578             return 0;
579         }
580     }
581 
582     switch (address_type){
583         case BD_ADDR_TYPE_UNKNOWN:
584             log_error("hci_number_free_acl_slots: unknown address type");
585             return 0;
586 
587         case BD_ADDR_TYPE_ACL:
588             return free_slots_classic;
589 
590         default:
591            if (hci_stack->le_acl_packets_total_num){
592                return free_slots_le;
593            }
594            return free_slots_classic;
595     }
596 }
597 
598 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
599     // get connection type
600     hci_connection_t * connection = hci_connection_for_handle(con_handle);
601     if (!connection){
602         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
603         return 0;
604     }
605     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
606 }
607 
608 #ifdef ENABLE_CLASSIC
609 static int hci_number_free_sco_slots(void){
610     unsigned int num_sco_packets_sent  = 0;
611     btstack_linked_item_t *it;
612     if (hci_stack->synchronous_flow_control_enabled){
613         // explicit flow control
614         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
615             hci_connection_t * connection = (hci_connection_t *) it;
616             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
617             num_sco_packets_sent += connection->num_packets_sent;
618         }
619         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
620             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
621             return 0;
622         }
623         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
624     } else {
625         // implicit flow control -- TODO
626         int num_ready = 0;
627         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
628             hci_connection_t * connection = (hci_connection_t *) it;
629             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
630             if (connection->sco_tx_ready == 0) continue;
631             num_ready++;
632         }
633         return num_ready;
634     }
635 }
636 #endif
637 
638 // only used to send HCI Host Number Completed Packets
639 static int hci_can_send_comand_packet_transport(void){
640     if (hci_stack->hci_packet_buffer_reserved) return 0;
641 
642     // check for async hci transport implementations
643     if (hci_stack->hci_transport->can_send_packet_now){
644         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
645             return 0;
646         }
647     }
648     return 1;
649 }
650 
651 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
652 bool hci_can_send_command_packet_now(void){
653     if (hci_can_send_comand_packet_transport() == 0) return false;
654     return hci_stack->num_cmd_packets > 0u;
655 }
656 
657 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
658     // check for async hci transport implementations
659     if (!hci_stack->hci_transport->can_send_packet_now) return true;
660     return hci_stack->hci_transport->can_send_packet_now(packet_type);
661 }
662 
663 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
664     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
665     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
666 }
667 
668 bool hci_can_send_acl_le_packet_now(void){
669     if (hci_stack->hci_packet_buffer_reserved) return false;
670     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
671 }
672 
673 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
674     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
675     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
676 }
677 
678 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
679     if (hci_stack->hci_packet_buffer_reserved) return false;
680     return hci_can_send_prepared_acl_packet_now(con_handle);
681 }
682 
683 #ifdef ENABLE_CLASSIC
684 bool hci_can_send_acl_classic_packet_now(void){
685     if (hci_stack->hci_packet_buffer_reserved) return false;
686     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
687 }
688 
689 bool hci_can_send_prepared_sco_packet_now(void){
690     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
691     if (hci_have_usb_transport()){
692         return hci_stack->sco_can_send_now;
693     } else {
694         return hci_number_free_sco_slots() > 0;
695     }
696 }
697 
698 bool hci_can_send_sco_packet_now(void){
699     if (hci_stack->hci_packet_buffer_reserved) return false;
700     return hci_can_send_prepared_sco_packet_now();
701 }
702 
703 void hci_request_sco_can_send_now_event(void){
704     hci_stack->sco_waiting_for_can_send_now = 1;
705     hci_notify_if_sco_can_send_now();
706 }
707 #endif
708 
709 // used for internal checks in l2cap.c
710 bool hci_is_packet_buffer_reserved(void){
711     return hci_stack->hci_packet_buffer_reserved;
712 }
713 
714 // reserves outgoing packet buffer. @returns 1 if successful
715 bool hci_reserve_packet_buffer(void){
716     if (hci_stack->hci_packet_buffer_reserved) {
717         log_error("hci_reserve_packet_buffer called but buffer already reserved");
718         return false;
719     }
720     hci_stack->hci_packet_buffer_reserved = true;
721     return true;
722 }
723 
724 void hci_release_packet_buffer(void){
725     hci_stack->hci_packet_buffer_reserved = false;
726 }
727 
728 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
729 static int hci_transport_synchronous(void){
730     return hci_stack->hci_transport->can_send_packet_now == NULL;
731 }
732 
733 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
734 
735     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
736 
737     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
738     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
739     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
740         max_acl_data_packet_length = hci_stack->le_data_packets_length;
741     }
742 
743 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
744     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
745         max_acl_data_packet_length = connection->le_max_tx_octets;
746     }
747 #endif
748 
749     log_debug("hci_send_acl_packet_fragments entered");
750 
751     uint8_t status = ERROR_CODE_SUCCESS;
752     // multiple packets could be send on a synchronous HCI transport
753     while (true){
754 
755         log_debug("hci_send_acl_packet_fragments loop entered");
756 
757         // get current data
758         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
759         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
760         bool more_fragments = false;
761 
762         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
763         if (current_acl_data_packet_length > max_acl_data_packet_length){
764             more_fragments = true;
765             current_acl_data_packet_length = max_acl_data_packet_length;
766         }
767 
768         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
769         if (acl_header_pos > 0u){
770             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
771             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
772             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
773         }
774 
775         // update header len
776         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
777 
778         // count packet
779         connection->num_packets_sent++;
780         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
781 
782         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
783         if (more_fragments){
784             // update start of next fragment to send
785             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
786         } else {
787             // done
788             hci_stack->acl_fragmentation_pos = 0;
789             hci_stack->acl_fragmentation_total_size = 0;
790         }
791 
792         // send packet
793         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
794         const int size = current_acl_data_packet_length + 4;
795         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
796         hci_stack->acl_fragmentation_tx_active = 1;
797         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
798         if (err != 0){
799             // no error from HCI Transport expected
800             status = ERROR_CODE_HARDWARE_FAILURE;
801         }
802 
803         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
804 
805         // done yet?
806         if (!more_fragments) break;
807 
808         // can send more?
809         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
810     }
811 
812     log_debug("hci_send_acl_packet_fragments loop over");
813 
814     // release buffer now for synchronous transport
815     if (hci_transport_synchronous()){
816         hci_stack->acl_fragmentation_tx_active = 0;
817         hci_release_packet_buffer();
818         hci_emit_transport_packet_sent();
819     }
820 
821     return status;
822 }
823 
824 // pre: caller has reserved the packet buffer
825 uint8_t hci_send_acl_packet_buffer(int size){
826     btstack_assert(hci_stack->hci_packet_buffer_reserved);
827 
828     uint8_t * packet = hci_stack->hci_packet_buffer;
829     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
830 
831     // check for free places on Bluetooth module
832     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
833         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
834         hci_release_packet_buffer();
835         hci_emit_transport_packet_sent();
836         return BTSTACK_ACL_BUFFERS_FULL;
837     }
838 
839     hci_connection_t *connection = hci_connection_for_handle( con_handle);
840     if (!connection) {
841         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
842         hci_release_packet_buffer();
843         hci_emit_transport_packet_sent();
844         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
845     }
846 
847 #ifdef ENABLE_CLASSIC
848     hci_connection_timestamp(connection);
849 #endif
850 
851     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
852 
853     // setup data
854     hci_stack->acl_fragmentation_total_size = size;
855     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
856 
857     return hci_send_acl_packet_fragments(connection);
858 }
859 
860 #ifdef ENABLE_CLASSIC
861 // pre: caller has reserved the packet buffer
862 uint8_t hci_send_sco_packet_buffer(int size){
863     btstack_assert(hci_stack->hci_packet_buffer_reserved);
864 
865     uint8_t * packet = hci_stack->hci_packet_buffer;
866 
867     // skip checks in loopback mode
868     if (!hci_stack->loopback_mode){
869         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
870 
871         // check for free places on Bluetooth module
872         if (!hci_can_send_prepared_sco_packet_now()) {
873             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
874             hci_release_packet_buffer();
875             hci_emit_transport_packet_sent();
876             return BTSTACK_ACL_BUFFERS_FULL;
877         }
878 
879         // track send packet in connection struct
880         hci_connection_t *connection = hci_connection_for_handle( con_handle);
881         if (!connection) {
882             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
883             hci_release_packet_buffer();
884             hci_emit_transport_packet_sent();
885             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
886         }
887 
888         if (hci_have_usb_transport()){
889             // token used
890             hci_stack->sco_can_send_now = false;
891         } else {
892             if (hci_stack->synchronous_flow_control_enabled){
893                 connection->num_packets_sent++;
894             } else {
895                 connection->sco_tx_ready--;
896             }
897         }
898     }
899 
900     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
901 
902 #ifdef HAVE_SCO_TRANSPORT
903     hci_stack->sco_transport->send_packet(packet, size);
904     hci_release_packet_buffer();
905     hci_emit_transport_packet_sent();
906 
907     return 0;
908 #else
909     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
910     if (hci_transport_synchronous()){
911         hci_release_packet_buffer();
912         hci_emit_transport_packet_sent();
913     }
914 
915     if (err != 0){
916         return ERROR_CODE_HARDWARE_FAILURE;
917     }
918     return ERROR_CODE_SUCCESS;
919 #endif
920 }
921 #endif
922 
923 static void acl_handler(uint8_t *packet, uint16_t size){
924 
925     // get info
926     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
927     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
928     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
929     uint16_t acl_length         = READ_ACL_LENGTH(packet);
930 
931     // ignore non-registered handle
932     if (!conn){
933         log_error("acl_handler called with non-registered handle %u!" , con_handle);
934         return;
935     }
936 
937     // assert packet is complete
938     if ((acl_length + 4u) != size){
939         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
940         return;
941     }
942 
943 #ifdef ENABLE_CLASSIC
944     // update idle timestamp
945     hci_connection_timestamp(conn);
946 #endif
947 
948 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
949     hci_stack->host_completed_packets = 1;
950     conn->num_packets_completed++;
951 #endif
952 
953     // handle different packet types
954     switch (acl_flags & 0x03u) {
955 
956         case 0x01: // continuation fragment
957 
958             // sanity checks
959             if (conn->acl_recombination_pos == 0u) {
960                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
961                 return;
962             }
963             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
964                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
965                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
966                 conn->acl_recombination_pos = 0;
967                 return;
968             }
969 
970             // append fragment payload (header already stored)
971             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
972                          &packet[4], acl_length);
973             conn->acl_recombination_pos += acl_length;
974 
975             // forward complete L2CAP packet if complete.
976             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
977                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
978                 // reset recombination buffer
979                 conn->acl_recombination_length = 0;
980                 conn->acl_recombination_pos = 0;
981             }
982             break;
983 
984         case 0x02: { // first fragment
985 
986             // sanity check
987             if (conn->acl_recombination_pos) {
988                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
989                 conn->acl_recombination_pos = 0;
990             }
991 
992             // peek into L2CAP packet!
993             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
994 
995             // compare fragment size to L2CAP packet size
996             if (acl_length >= (l2cap_length + 4u)){
997                 // forward fragment as L2CAP packet
998                 hci_emit_acl_packet(packet, acl_length + 4u);
999             } else {
1000 
1001                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1002                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1003                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1004                     return;
1005                 }
1006 
1007                 // store first fragment and tweak acl length for complete package
1008                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1009                              packet, acl_length + 4u);
1010                 conn->acl_recombination_pos    = acl_length + 4u;
1011                 conn->acl_recombination_length = l2cap_length;
1012                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1013             }
1014             break;
1015 
1016         }
1017         default:
1018             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1019             return;
1020     }
1021 
1022     // execute main loop
1023     hci_run();
1024 }
1025 
1026 static void hci_connection_stop_timer(hci_connection_t * conn){
1027     btstack_run_loop_remove_timer(&conn->timeout);
1028 #ifdef ENABLE_CLASSIC
1029     btstack_run_loop_remove_timer(&conn->timeout_sco);
1030 #endif
1031 }
1032 
1033 static void hci_shutdown_connection(hci_connection_t *conn){
1034     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1035 
1036 #ifdef ENABLE_CLASSIC
1037 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1038     bd_addr_type_t addr_type = conn->address_type;
1039 #endif
1040 #ifdef HAVE_SCO_TRANSPORT
1041     hci_con_handle_t con_handle = conn->con_handle;
1042 #endif
1043 #endif
1044 
1045     hci_connection_stop_timer(conn);
1046 
1047     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1048     btstack_memory_hci_connection_free( conn );
1049 
1050     // now it's gone
1051     hci_emit_nr_connections_changed();
1052 
1053 #ifdef ENABLE_CLASSIC
1054 #ifdef ENABLE_SCO_OVER_HCI
1055     // update SCO
1056     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1057         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1058     }
1059 #endif
1060 #ifdef HAVE_SCO_TRANSPORT
1061     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1062         hci_stack->sco_transport->close(con_handle);
1063     }
1064 #endif
1065 #endif
1066 }
1067 
1068 #ifdef ENABLE_CLASSIC
1069 
1070 static const uint16_t packet_type_sizes[] = {
1071     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1072     HCI_ACL_DH1_SIZE, 0, 0, 0,
1073     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1074     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1075 };
1076 static const uint8_t  packet_type_feature_requirement_bit[] = {
1077      0, // 3 slot packets
1078      1, // 5 slot packets
1079     25, // EDR 2 mpbs
1080     26, // EDR 3 mbps
1081     39, // 3 slot EDR packts
1082     40, // 5 slot EDR packet
1083 };
1084 static const uint16_t packet_type_feature_packet_mask[] = {
1085     0x0f00, // 3 slot packets
1086     0xf000, // 5 slot packets
1087     0x1102, // EDR 2 mpbs
1088     0x2204, // EDR 3 mbps
1089     0x0300, // 3 slot EDR packts
1090     0x3000, // 5 slot EDR packet
1091 };
1092 
1093 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1094     // enable packet types based on size
1095     uint16_t packet_types = 0;
1096     unsigned int i;
1097     for (i=0;i<16;i++){
1098         if (packet_type_sizes[i] == 0) continue;
1099         if (packet_type_sizes[i] <= buffer_size){
1100             packet_types |= 1 << i;
1101         }
1102     }
1103     // disable packet types due to missing local supported features
1104     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1105         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1106         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1107         if (feature_set) continue;
1108         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1109         packet_types &= ~packet_type_feature_packet_mask[i];
1110     }
1111     // flip bits for "may not be used"
1112     packet_types ^= 0x3306;
1113     return packet_types;
1114 }
1115 
1116 uint16_t hci_usable_acl_packet_types(void){
1117     return hci_stack->packet_types;
1118 }
1119 #endif
1120 
1121 uint8_t* hci_get_outgoing_packet_buffer(void){
1122     // hci packet buffer is >= acl data packet length
1123     return hci_stack->hci_packet_buffer;
1124 }
1125 
1126 uint16_t hci_max_acl_data_packet_length(void){
1127     return hci_stack->acl_data_packet_length;
1128 }
1129 
1130 #ifdef ENABLE_CLASSIC
1131 bool hci_extended_sco_link_supported(void){
1132     // No. 31, byte 3, bit 7
1133     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1134 }
1135 #endif
1136 
1137 bool hci_non_flushable_packet_boundary_flag_supported(void){
1138     // No. 54, byte 6, bit 6
1139     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1140 }
1141 
1142 static int gap_ssp_supported(void){
1143     // No. 51, byte 6, bit 3
1144     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1145 }
1146 
1147 static int hci_classic_supported(void){
1148 #ifdef ENABLE_CLASSIC
1149     // No. 37, byte 4, bit 5, = No BR/EDR Support
1150     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1151 #else
1152     return 0;
1153 #endif
1154 }
1155 
1156 static int hci_le_supported(void){
1157 #ifdef ENABLE_BLE
1158     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1159     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1160 #else
1161     return 0;
1162 #endif
1163 }
1164 
1165 #ifdef ENABLE_BLE
1166 
1167 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1168     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1169         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1170     } else {
1171         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1172     }
1173 }
1174 
1175 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1176     *addr_type = hci_stack->le_own_addr_type;
1177     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1178 }
1179 
1180 #ifdef ENABLE_LE_PERIPHERAL
1181 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1182     *addr_type = hci_stack->le_advertisements_own_addr_type;
1183     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1184 };
1185 #endif
1186 
1187 #ifdef ENABLE_LE_CENTRAL
1188 
1189 /**
1190  * @brief Get own addr type and address used for LE connections (Central)
1191  */
1192 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1193     *addr_type = hci_stack->le_connection_own_addr_type;
1194     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1195 }
1196 
1197 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1198 
1199     int offset = 3;
1200     int num_reports = packet[offset];
1201     offset += 1;
1202 
1203     int i;
1204     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1205     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1206     for (i=0; (i<num_reports) && (offset < size);i++){
1207         // sanity checks on data_length:
1208         uint8_t data_length = packet[offset + 8];
1209         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1210         if ((offset + 9u + data_length + 1u) > size)    return;
1211         // setup event
1212         uint8_t event_size = 10u + data_length;
1213         int pos = 0;
1214         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1215         event[pos++] = event_size;
1216         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1217         offset += 8;
1218         pos += 8;
1219         event[pos++] = packet[offset + 1 + data_length]; // rssi
1220         event[pos++] = data_length;
1221         offset++;
1222         (void)memcpy(&event[pos], &packet[offset], data_length);
1223         pos +=    data_length;
1224         offset += data_length + 1u; // rssi
1225         hci_emit_event(event, pos, 1);
1226     }
1227 }
1228 #endif
1229 #endif
1230 
1231 #ifdef ENABLE_BLE
1232 #ifdef ENABLE_LE_PERIPHERAL
1233 static void hci_update_advertisements_enabled_for_current_roles(void){
1234     if (hci_stack->le_advertisements_enabled){
1235         // get number of active le slave connections
1236         int num_slave_connections = 0;
1237         btstack_linked_list_iterator_t it;
1238         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1239         while (btstack_linked_list_iterator_has_next(&it)){
1240             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1241             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1242             if (con->state != OPEN) continue;
1243             if (con->role  != HCI_ROLE_SLAVE) continue;
1244             if (!hci_is_le_connection(con)) continue;
1245             num_slave_connections++;
1246         }
1247         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1248         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1249     } else {
1250         hci_stack->le_advertisements_enabled_for_current_roles = false;
1251     }
1252 }
1253 #endif
1254 #endif
1255 
1256 #ifdef ENABLE_CLASSIC
1257 static void gap_run_set_local_name(void){
1258     hci_reserve_packet_buffer();
1259     uint8_t * packet = hci_stack->hci_packet_buffer;
1260     // construct HCI Command and send
1261     uint16_t opcode = hci_write_local_name.opcode;
1262     hci_stack->last_cmd_opcode = opcode;
1263     packet[0] = opcode & 0xff;
1264     packet[1] = opcode >> 8;
1265     packet[2] = DEVICE_NAME_LEN;
1266     memset(&packet[3], 0, DEVICE_NAME_LEN);
1267     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1268     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1269     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1270     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1271     // expand '00:00:00:00:00:00' in name with bd_addr
1272     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1273     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1274 }
1275 
1276 static void gap_run_set_eir_data(void){
1277     hci_reserve_packet_buffer();
1278     uint8_t * packet = hci_stack->hci_packet_buffer;
1279     // construct HCI Command in-place and send
1280     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1281     hci_stack->last_cmd_opcode = opcode;
1282     uint16_t offset = 0;
1283     packet[offset++] = opcode & 0xff;
1284     packet[offset++] = opcode >> 8;
1285     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1286     packet[offset++] = 0;  // FEC not required
1287     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1288     if (hci_stack->eir_data){
1289         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1290         ad_context_t context;
1291         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1292             uint8_t data_type   = ad_iterator_get_data_type(&context);
1293             uint8_t size        = ad_iterator_get_data_len(&context);
1294             const uint8_t *data = ad_iterator_get_data(&context);
1295             // copy item
1296             packet[offset++] = size + 1;
1297             packet[offset++] = data_type;
1298             memcpy(&packet[offset], data, size);
1299             // update name item
1300             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1301                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1302             }
1303             offset += size;
1304         }
1305     } else {
1306         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1307         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1308         packet[offset++] = bytes_to_copy + 1;
1309         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1310         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1311         // expand '00:00:00:00:00:00' in name with bd_addr
1312         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1313     }
1314     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1315 }
1316 
1317 static void hci_run_gap_tasks_classic(void){
1318     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1319         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1320         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1321         return;
1322     }
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1325         gap_run_set_local_name();
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1330         gap_run_set_eir_data();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1335         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1336         return;
1337     }
1338     // write page scan activity
1339     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1340         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1341         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1342         return;
1343     }
1344     // write page scan type
1345     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1346         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1347         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1348         return;
1349     }
1350     // send scan enable
1351     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1352         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1353         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1354         return;
1355     }
1356 }
1357 #endif
1358 
1359 #ifndef HAVE_HOST_CONTROLLER_API
1360 
1361 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1362     if (!hci_stack->config) return 0;
1363     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1364     // Limit baud rate for Broadcom chipsets to 3 mbps
1365     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1366         baud_rate = 3000000;
1367     }
1368     return baud_rate;
1369 }
1370 
1371 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1372     UNUSED(ds);
1373 
1374     switch (hci_stack->substate){
1375         case HCI_INIT_W4_SEND_RESET:
1376             log_info("Resend HCI Reset");
1377             hci_stack->substate = HCI_INIT_SEND_RESET;
1378             hci_stack->num_cmd_packets = 1;
1379             hci_run();
1380             break;
1381         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1382             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1383             if (hci_stack->hci_transport->reset_link){
1384                 hci_stack->hci_transport->reset_link();
1385             }
1386 
1387             /* fall through */
1388 
1389         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1390             log_info("Resend HCI Reset - CSR Warm Boot");
1391             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1392             hci_stack->num_cmd_packets = 1;
1393             hci_run();
1394             break;
1395         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1396             if (hci_stack->hci_transport->set_baudrate){
1397                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1398                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1399                 hci_stack->hci_transport->set_baudrate(baud_rate);
1400             }
1401             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1402             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1403                 if (hci_stack->hci_transport->reset_link){
1404                     log_info("Link Reset");
1405                     hci_stack->hci_transport->reset_link();
1406                 }
1407                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1408                 hci_run();
1409             }
1410             break;
1411         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1412             // otherwise continue
1413             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1414             hci_send_cmd(&hci_read_local_supported_commands);
1415             break;
1416         default:
1417             break;
1418     }
1419 }
1420 #endif
1421 
1422 static void hci_initializing_next_state(void){
1423     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1424 }
1425 
1426 static void hci_init_done(void){
1427     // done. tell the app
1428     log_info("hci_init_done -> HCI_STATE_WORKING");
1429     hci_stack->state = HCI_STATE_WORKING;
1430     hci_emit_state();
1431 }
1432 
1433 // assumption: hci_can_send_command_packet_now() == true
1434 static void hci_initializing_run(void){
1435     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1436 
1437 #ifndef HAVE_HOST_CONTROLLER_API
1438     bool need_baud_change = hci_stack->config
1439             && hci_stack->chipset
1440             && hci_stack->chipset->set_baudrate_command
1441             && hci_stack->hci_transport->set_baudrate
1442             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1443 #endif
1444 
1445     switch (hci_stack->substate){
1446         case HCI_INIT_SEND_RESET:
1447             hci_state_reset();
1448 
1449 #ifndef HAVE_HOST_CONTROLLER_API
1450             // prepare reset if command complete not received in 100ms
1451             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1452             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1453             btstack_run_loop_add_timer(&hci_stack->timeout);
1454 #endif
1455             // send command
1456             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1457             hci_send_cmd(&hci_reset);
1458             break;
1459         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1460             hci_send_cmd(&hci_read_local_version_information);
1461             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1462             break;
1463 
1464 #ifndef HAVE_HOST_CONTROLLER_API
1465         case HCI_INIT_SEND_READ_LOCAL_NAME:
1466             hci_send_cmd(&hci_read_local_name);
1467             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1468             break;
1469         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1470             hci_state_reset();
1471             // prepare reset if command complete not received in 100ms
1472             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1473             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1474             btstack_run_loop_add_timer(&hci_stack->timeout);
1475             // send command
1476             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1477             hci_send_cmd(&hci_reset);
1478             break;
1479         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1480             hci_state_reset();
1481             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1482             hci_send_cmd(&hci_reset);
1483             break;
1484         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1485             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1486             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1487             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1488             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1489             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1490             break;
1491         }
1492         case HCI_INIT_SET_BD_ADDR:
1493             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1494             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1495             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1496             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1497             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1498             break;
1499         case HCI_INIT_SEND_BAUD_CHANGE:
1500             if (need_baud_change) {
1501                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1502                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1503                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1504                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1505                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1506                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1507                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1508                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1509                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1510                     btstack_run_loop_add_timer(&hci_stack->timeout);
1511                }
1512                break;
1513             }
1514 
1515             /* fall through */
1516 
1517         case HCI_INIT_CUSTOM_INIT:
1518             // Custom initialization
1519             if (hci_stack->chipset && hci_stack->chipset->next_command){
1520                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1521                 bool send_cmd = false;
1522                 switch (hci_stack->chipset_result){
1523                     case BTSTACK_CHIPSET_VALID_COMMAND:
1524                         send_cmd = true;
1525                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1526                         break;
1527                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1528                         send_cmd = true;
1529                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1530                         log_info("CSR Warm Boot");
1531                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1532                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1533                         btstack_run_loop_add_timer(&hci_stack->timeout);
1534                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1535                             && hci_stack->config
1536                             && hci_stack->chipset
1537                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1538                             && hci_stack->hci_transport->set_baudrate
1539                             && hci_transport_uart_get_main_baud_rate()){
1540                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1541                         } else {
1542                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1543                         }
1544                         break;
1545                     default:
1546                         break;
1547                 }
1548 
1549                 if (send_cmd){
1550                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1551                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1552                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1553                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1554                     break;
1555                 }
1556                 log_info("Init script done");
1557 
1558                 // Init script download on Broadcom chipsets causes:
1559                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1560                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1561                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1562 
1563                     // - baud rate to reset, restore UART baud rate if needed
1564                     if (need_baud_change) {
1565                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1566                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1567                         hci_stack->hci_transport->set_baudrate(baud_rate);
1568                     }
1569 
1570                     uint16_t bcm_delay_ms = 300;
1571                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1572                     //   -> Work around: wait here.
1573                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1574                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1575                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1576                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1577                     btstack_run_loop_add_timer(&hci_stack->timeout);
1578                     break;
1579                 }
1580             }
1581             /* fall through */
1582 #endif
1583 
1584         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1585             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1586             hci_send_cmd(&hci_read_local_supported_commands);
1587             break;
1588         case HCI_INIT_READ_BD_ADDR:
1589             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1590             hci_send_cmd(&hci_read_bd_addr);
1591             break;
1592         case HCI_INIT_READ_BUFFER_SIZE:
1593             // only read buffer size if supported
1594             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1595                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1596                 hci_send_cmd(&hci_read_buffer_size);
1597                 break;
1598             }
1599             /* fall through */
1600 
1601         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1602             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1603             hci_send_cmd(&hci_read_local_supported_features);
1604             break;
1605 
1606 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1607         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1608             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1609             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1610             break;
1611         case HCI_INIT_HOST_BUFFER_SIZE:
1612             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1613             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1614                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1615             break;
1616 #endif
1617 
1618         case HCI_INIT_SET_EVENT_MASK:
1619             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1620             if (hci_le_supported()){
1621                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1622             } else {
1623                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1624                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1625             }
1626             break;
1627 
1628 #ifdef ENABLE_CLASSIC
1629         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1630             if (hci_classic_supported() && gap_ssp_supported()){
1631                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1632                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1633                 break;
1634             }
1635             /* fall through */
1636 
1637         case HCI_INIT_WRITE_INQUIRY_MODE:
1638             if (hci_classic_supported()){
1639                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1640                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1641                 break;
1642             }
1643             /* fall through */
1644 
1645         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1646             // skip write secure connections host support if not supported or disabled
1647             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1648                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1649                 hci_stack->secure_connections_active = true;
1650                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1651                 break;
1652             }
1653             /* fall through */
1654 
1655         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1656             if (hci_classic_supported()){
1657                 hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1658                 hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1659                 break;
1660             }
1661             /* fall through */
1662 
1663 #ifdef ENABLE_SCO_OVER_HCI
1664         // only sent if ENABLE_SCO_OVER_HCI is defined
1665         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1666             // skip write synchronous flow control if not supported
1667             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1668                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1669                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1670                 break;
1671             }
1672             /* fall through */
1673 
1674         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1675             // skip write default erroneous data reporting if not supported
1676             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1677                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1678                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1679                 break;
1680             }
1681             /* fall through */
1682 #endif
1683 
1684 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1685         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1686         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1687             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1688                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1689 #ifdef ENABLE_SCO_OVER_HCI
1690                 log_info("BCM: Route SCO data via HCI transport");
1691                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1692 #endif
1693 #ifdef ENABLE_SCO_OVER_PCM
1694                 log_info("BCM: Route SCO data via PCM interface");
1695 #ifdef ENABLE_BCM_PCM_WBS
1696                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1697                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1698 #else
1699                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1700                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1701 #endif
1702 #endif
1703                 break;
1704             }
1705             /* fall through */
1706 #endif
1707 
1708 #ifdef ENABLE_SCO_OVER_PCM
1709         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1710             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1711                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1712                 log_info("BCM: Config PCM interface for I2S");
1713 #ifdef ENABLE_BCM_PCM_WBS
1714                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1715                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1716 #else
1717                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1718                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1719 #endif
1720                 break;
1721             }
1722             /* fall through */
1723 #endif
1724 #endif
1725 
1726 #ifdef ENABLE_BLE
1727         // LE INIT
1728         case HCI_INIT_LE_READ_BUFFER_SIZE:
1729             if (hci_le_supported()){
1730                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1731                 hci_send_cmd(&hci_le_read_buffer_size);
1732                 break;
1733             }
1734             /* fall through */
1735 
1736         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1737             // skip write le host if not supported (e.g. on LE only EM9301)
1738             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1739                 // LE Supported Host = 1, Simultaneous Host = 0
1740                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1741                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1742                 break;
1743             }
1744             /* fall through */
1745 
1746         case HCI_INIT_LE_SET_EVENT_MASK:
1747             if (hci_le_supported()){
1748                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1749                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1750                 break;
1751             }
1752             /* fall through */
1753 
1754 #endif
1755 
1756 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1757         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1758             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1759                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1760                 hci_send_cmd(&hci_le_read_maximum_data_length);
1761                 break;
1762             }
1763             /* fall through */
1764 
1765         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1766             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1767                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1768                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1769                 break;
1770             }
1771             /* fall through */
1772 #endif
1773 
1774 #ifdef ENABLE_LE_CENTRAL
1775         case HCI_INIT_READ_WHITE_LIST_SIZE:
1776             if (hci_le_supported()){
1777                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1778                 hci_send_cmd(&hci_le_read_white_list_size);
1779                 break;
1780             }
1781             /* fall through */
1782 
1783         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1784             if (hci_le_supported()){
1785                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1786                 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);
1787                 break;
1788             }
1789             /* fall through */
1790 #endif
1791 
1792         case HCI_INIT_DONE:
1793             hci_stack->substate = HCI_INIT_DONE;
1794 #ifdef ENABLE_CLASSIC
1795             // init sequence complete, check if GAP Tasks are completed
1796             if (hci_stack->gap_tasks != 0) {
1797                 hci_run_gap_tasks_classic();
1798                 break;
1799             }
1800 #endif
1801             hci_init_done();
1802             break;
1803 
1804         default:
1805             return;
1806     }
1807 }
1808 
1809 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1810     bool command_completed = false;
1811     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1812         uint16_t opcode = little_endian_read_16(packet,3);
1813         if (opcode == hci_stack->last_cmd_opcode){
1814             command_completed = true;
1815             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1816         } else {
1817             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1818         }
1819     }
1820 
1821     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1822         uint8_t  status = packet[2];
1823         uint16_t opcode = little_endian_read_16(packet,4);
1824         if (opcode == hci_stack->last_cmd_opcode){
1825             if (status){
1826                 command_completed = true;
1827                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1828             } else {
1829                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1830             }
1831         } else {
1832             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1833         }
1834     }
1835 #ifndef HAVE_HOST_CONTROLLER_API
1836     // Vendor == CSR
1837     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1838         // TODO: track actual command
1839         command_completed = true;
1840     }
1841 
1842     // Vendor == Toshiba
1843     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1844         // TODO: track actual command
1845         command_completed = true;
1846         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1847         hci_stack->num_cmd_packets = 1;
1848     }
1849 #endif
1850 
1851     return command_completed;
1852 }
1853 
1854 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1855 
1856     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1857 
1858     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1859 
1860 #ifndef HAVE_HOST_CONTROLLER_API
1861 
1862     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1863     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1864     //
1865     // HCI Reset
1866     // Timeout 100 ms
1867     // HCI Reset
1868     // Command Complete Reset
1869     // HCI Read Local Version Information
1870     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1871     // hang...
1872     //
1873     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1874     if (!command_completed
1875             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1876             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1877 
1878         uint16_t opcode = little_endian_read_16(packet,3);
1879         if (opcode == hci_reset.opcode){
1880             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1881             return;
1882         }
1883     }
1884 
1885     // CSR & H5
1886     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1887     if (!command_completed
1888             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1889             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1890 
1891         uint16_t opcode = little_endian_read_16(packet,3);
1892         if (opcode == hci_reset.opcode){
1893             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1894             return;
1895         }
1896     }
1897 
1898     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1899     // fix: Correct substate and behave as command below
1900     if (command_completed){
1901         switch (hci_stack->substate){
1902             case HCI_INIT_SEND_RESET:
1903                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1904                 break;
1905             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1906                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1907                 break;
1908             default:
1909                 break;
1910         }
1911     }
1912 
1913 #endif
1914 
1915     if (!command_completed) return;
1916 
1917     bool need_baud_change = false;
1918     bool need_addr_change = false;
1919 
1920 #ifndef HAVE_HOST_CONTROLLER_API
1921     need_baud_change = hci_stack->config
1922                         && hci_stack->chipset
1923                         && hci_stack->chipset->set_baudrate_command
1924                         && hci_stack->hci_transport->set_baudrate
1925                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1926 
1927     need_addr_change = hci_stack->custom_bd_addr_set
1928                         && hci_stack->chipset
1929                         && hci_stack->chipset->set_bd_addr_command;
1930 #endif
1931 
1932     switch(hci_stack->substate){
1933 
1934 #ifndef HAVE_HOST_CONTROLLER_API
1935         case HCI_INIT_SEND_RESET:
1936             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1937             // fix: just correct substate and behave as command below
1938 
1939             /* fall through */
1940 #endif
1941 
1942         case HCI_INIT_W4_SEND_RESET:
1943             btstack_run_loop_remove_timer(&hci_stack->timeout);
1944             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1945             return;
1946 
1947 #ifndef HAVE_HOST_CONTROLLER_API
1948         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1949             // for STLC2500D, baud rate change already happened.
1950             // for others, baud rate gets changed now
1951             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1952                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1953                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1954                 hci_stack->hci_transport->set_baudrate(baud_rate);
1955             }
1956             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1957             return;
1958         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1959             btstack_run_loop_remove_timer(&hci_stack->timeout);
1960             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1961             return;
1962         case HCI_INIT_W4_CUSTOM_INIT:
1963             // repeat custom init
1964             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1965             return;
1966 #endif
1967 
1968         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1969             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1970               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1971                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1972                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1973                 return;
1974             }
1975             if (need_addr_change){
1976                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1977                 return;
1978             }
1979             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1980             return;
1981 #ifndef HAVE_HOST_CONTROLLER_API
1982         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1983             if (need_baud_change){
1984                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1985                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1986                 hci_stack->hci_transport->set_baudrate(baud_rate);
1987             }
1988             if (need_addr_change){
1989                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1990                 return;
1991             }
1992             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1993             return;
1994         case HCI_INIT_W4_SET_BD_ADDR:
1995             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1996             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1997             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1998                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1999                 return;
2000             }
2001             // skipping st warm boot
2002             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2003             return;
2004         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2005             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2006             return;
2007 #endif
2008 
2009         case HCI_INIT_DONE:
2010             // set state if we came here by fall through
2011             hci_stack->substate = HCI_INIT_DONE;
2012             return;
2013 
2014         default:
2015             break;
2016     }
2017     hci_initializing_next_state();
2018 }
2019 
2020 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2021     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2022     bd_addr_t bd_address;
2023     (void)memcpy(&bd_address, conn->address, 6);
2024 
2025 #ifdef ENABLE_CLASSIC
2026     // cache needed data
2027     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2028 #endif
2029 
2030     // connection failed, remove entry
2031     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2032     btstack_memory_hci_connection_free( conn );
2033 
2034 #ifdef ENABLE_CLASSIC
2035     // notify client if dedicated bonding
2036     if (notify_dedicated_bonding_failed){
2037         log_info("hci notify_dedicated_bonding_failed");
2038         hci_emit_dedicated_bonding_result(bd_address, status);
2039     }
2040 
2041     // if authentication error, also delete link key
2042     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2043         gap_drop_link_key_for_bd_addr(bd_address);
2044     }
2045 #else
2046     UNUSED(status);
2047 #endif
2048 }
2049 
2050 #ifdef ENABLE_CLASSIC
2051 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2052     // SSP Controller
2053     if (features[6] & (1 << 3)){
2054         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2055     }
2056     // eSCO
2057     if (features[3] & (1<<7)){
2058         conn->remote_supported_features[0] |= 1;
2059     }
2060     // Extended features
2061     if (features[7] & (1<<7)){
2062         conn->remote_supported_features[0] |= 2;
2063     }
2064 }
2065 
2066 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2067     // SSP Host
2068     if (features[0] & (1 << 0)){
2069         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2070     }
2071     // SC Host
2072     if (features[0] & (1 << 3)){
2073         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2074     }
2075 }
2076 
2077 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2078     // SC Controller
2079     if (features[1] & (1 << 0)){
2080         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2081     }
2082 }
2083 
2084 static void hci_handle_remote_features_received(hci_connection_t * conn){
2085     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2086     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2087     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2088     if (conn->bonding_flags & BONDING_DEDICATED){
2089         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2090     }
2091 }
2092 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2093     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2094     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2095 }
2096 
2097 #endif
2098 
2099 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2100     // handle BT initialization
2101     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2102         hci_initializing_event_handler(packet, size);
2103     }
2104 
2105     // help with BT sleep
2106     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2107         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2108         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2109         hci_initializing_next_state();
2110     }
2111 }
2112 
2113 #ifdef ENABLE_CLASSIC
2114 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2115     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2116     conn->encryption_key_size = encryption_key_size;
2117 
2118     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2119         conn->requested_security_level = LEVEL_0;
2120         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2121         return;
2122     }
2123 
2124     // Request remote features if not already done
2125     if ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) == 0) {
2126         conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2127     }
2128 
2129     // Request Authentication if not already done
2130     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2131     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2132 }
2133 #endif
2134 
2135 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2136     UNUSED(size);
2137 
2138     uint16_t manufacturer;
2139 #ifdef ENABLE_CLASSIC
2140     hci_con_handle_t handle;
2141     hci_connection_t * conn;
2142     uint8_t status;
2143 #endif
2144     // get num cmd packets - limit to 1 to reduce complexity
2145     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2146 
2147     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2148     switch (opcode){
2149         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2150             if (packet[5]) break;
2151             // terminate, name 248 chars
2152             packet[6+248] = 0;
2153             log_info("local name: %s", &packet[6]);
2154             break;
2155         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2156             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2157             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2158                 uint16_t acl_len = little_endian_read_16(packet, 6);
2159                 uint16_t sco_len = packet[8];
2160 
2161                 // determine usable ACL/SCO payload size
2162                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2163                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2164 
2165                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2166                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2167 
2168                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2169                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2170                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2171             }
2172             break;
2173         case HCI_OPCODE_HCI_READ_RSSI:
2174             if (packet[5] == ERROR_CODE_SUCCESS){
2175                 uint8_t event[5];
2176                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2177                 event[1] = 3;
2178                 (void)memcpy(&event[2], &packet[6], 3);
2179                 hci_emit_event(event, sizeof(event), 1);
2180             }
2181             break;
2182 #ifdef ENABLE_BLE
2183         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2184             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2185             hci_stack->le_acl_packets_total_num = packet[8];
2186             // determine usable ACL payload size
2187             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2188                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2189             }
2190             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2191             break;
2192 #endif
2193 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2194         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2195             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2196             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2197             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);
2198             break;
2199 #endif
2200 #ifdef ENABLE_LE_CENTRAL
2201         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2202             hci_stack->le_whitelist_capacity = packet[6];
2203             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2204             break;
2205 #endif
2206         case HCI_OPCODE_HCI_READ_BD_ADDR:
2207             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2208             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));
2209 #ifdef ENABLE_CLASSIC
2210             if (hci_stack->link_key_db){
2211                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2212             }
2213 #endif
2214             break;
2215 #ifdef ENABLE_CLASSIC
2216         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2217             hci_emit_discoverable_enabled(hci_stack->discoverable);
2218             break;
2219         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2220             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2221                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2222                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2223                 hci_emit_event(event, sizeof(event), 1);
2224             }
2225             break;
2226 #endif
2227         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2228             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2229 
2230 #ifdef ENABLE_CLASSIC
2231             // determine usable ACL packet types based on host buffer size and supported features
2232             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2233             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2234 #endif
2235             // Classic/LE
2236             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2237             break;
2238         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2239             manufacturer = little_endian_read_16(packet, 10);
2240             // map Cypress to Broadcom
2241             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2242                 log_info("Treat Cypress as Broadcom");
2243                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2244                 little_endian_store_16(packet, 10, manufacturer);
2245             }
2246             hci_stack->manufacturer = manufacturer;
2247             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2248             break;
2249         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2250             hci_stack->local_supported_commands[0] =
2251                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2252                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2253                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2254                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2255                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2256                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2257                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2258                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2259             hci_stack->local_supported_commands[1] =
2260                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2261                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2262                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2263                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2264                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2265             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2266             break;
2267 #ifdef ENABLE_CLASSIC
2268         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2269             if (packet[5]) return;
2270             hci_stack->synchronous_flow_control_enabled = 1;
2271             break;
2272         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2273             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2274             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2275             conn   = hci_connection_for_handle(handle);
2276             if (conn != NULL) {
2277                 uint8_t key_size = 0;
2278                 if (status == 0){
2279                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2280                     log_info("Handle %04x key Size: %u", handle, key_size);
2281                 } else {
2282                     key_size = 1;
2283                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2284                 }
2285                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2286             }
2287             break;
2288         // assert pairing complete event is emitted.
2289         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2290         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2291         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2292         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2293             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2294             // lookup connection by gap pairing addr
2295             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2296             if (conn == NULL) break;
2297             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2298             break;
2299 
2300 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2301         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2302         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2303             uint8_t event[67];
2304             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2305             event[1] = 65;
2306             (void)memset(&event[2], 0, 65);
2307             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2308                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2309                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2310                     event[2] = 3;
2311                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2312                 } else {
2313                     event[2] = 1;
2314                 }
2315             }
2316             hci_emit_event(event, sizeof(event), 0);
2317             break;
2318         }
2319 
2320         // note: only needed if user does not provide OOB data
2321         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2322             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2323             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2324             if (conn == NULL) break;
2325             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2326             break;
2327 #endif
2328 #endif
2329         default:
2330             break;
2331     }
2332 }
2333 
2334 #ifdef ENABLE_BLE
2335 static void event_handle_le_connection_complete(const uint8_t * packet){
2336 	bd_addr_t addr;
2337 	bd_addr_type_t addr_type;
2338 	hci_connection_t * conn;
2339 
2340 	// Connection management
2341 	reverse_bd_addr(&packet[8], addr);
2342 	addr_type = (bd_addr_type_t)packet[7];
2343 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2344 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2345 
2346 #ifdef ENABLE_LE_CENTRAL
2347 	// handle error: error is reported only to the initiator -> outgoing connection
2348 	if (packet[3]){
2349 
2350 		// handle cancelled outgoing connection
2351 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2352 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2353 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2354 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2355 		    // reset state
2356             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2357             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2358 			// get outgoing connection conn struct for direct connect
2359 			conn = gap_get_outgoing_connection();
2360 		}
2361 
2362 		// outgoing le connection establishment is done
2363 		if (conn){
2364 			// remove entry
2365 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2366 			btstack_memory_hci_connection_free( conn );
2367 		}
2368 		return;
2369 	}
2370 #endif
2371 
2372 	// on success, both hosts receive connection complete event
2373 	if (packet[6] == HCI_ROLE_MASTER){
2374 #ifdef ENABLE_LE_CENTRAL
2375 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2376 		// note: no hci_connection_t object exists yet for connect with whitelist
2377 		if (hci_is_le_connection_type(addr_type)){
2378 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2379 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2380 		}
2381 #endif
2382 	} else {
2383 #ifdef ENABLE_LE_PERIPHERAL
2384 		// if we're slave, it was an incoming connection, advertisements have stopped
2385 		hci_stack->le_advertisements_active = false;
2386 #endif
2387 	}
2388 
2389 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2390 	if (!conn){
2391 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2392 	}
2393 
2394 	// no memory, sorry.
2395 	if (!conn){
2396 		return;
2397 	}
2398 
2399 	conn->state = OPEN;
2400 	conn->role  = packet[6];
2401 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2402 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2403 
2404 #ifdef ENABLE_LE_PERIPHERAL
2405 	if (packet[6] == HCI_ROLE_SLAVE){
2406 		hci_update_advertisements_enabled_for_current_roles();
2407 	}
2408 #endif
2409 
2410     // init unenhanced att bearer mtu
2411     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2412     conn->att_connection.mtu_exchanged = false;
2413 
2414     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2415 
2416 	// restart timer
2417 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2418 	// btstack_run_loop_add_timer(&conn->timeout);
2419 
2420 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2421 
2422 	hci_emit_nr_connections_changed();
2423 }
2424 #endif
2425 
2426 #ifdef ENABLE_CLASSIC
2427 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){
2428     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2429     // LEVEL_4 is tested by l2cap
2430     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2431     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2432     if (level >= LEVEL_3){
2433         // MITM not possible without keyboard or display
2434         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2435         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2436 
2437         // MITM possible if one side has keyboard and the other has keyboard or display
2438         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2439         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2440 
2441         // MITM not possible if one side has only display and other side has no keyboard
2442         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2443         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2444     }
2445     // LEVEL 2 requires SSP, which is a given
2446     return true;
2447 }
2448 
2449 static bool btstack_is_null(uint8_t * data, uint16_t size){
2450     uint16_t i;
2451     for (i=0; i < size ; i++){
2452         if (data[i] != 0) {
2453             return false;
2454         }
2455     }
2456     return true;
2457 }
2458 
2459 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2460     // get requested security level
2461     gap_security_level_t requested_security_level = conn->requested_security_level;
2462     if (hci_stack->gap_secure_connections_only_mode){
2463         requested_security_level = LEVEL_4;
2464     }
2465 
2466     // assess security: LEVEL 4 requires SC
2467     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2468     if ((requested_security_level == LEVEL_4) &&
2469         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2470         !hci_remote_sc_enabled(conn)){
2471         log_info("Level 4 required, but SC not supported -> abort");
2472         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2473         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2474         return;
2475     }
2476 
2477     // assess security based on io capabilities
2478     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2479         // responder: fully validate io caps of both sides as well as OOB data
2480         bool security_possible = false;
2481         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2482 
2483 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2484         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2485         // so we merge the OOB data availability
2486         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2487         if (conn->classic_oob_c_192 != NULL){
2488             have_oob_data |= 1;
2489         }
2490         if (conn->classic_oob_c_256 != NULL){
2491             have_oob_data |= 2;
2492         }
2493         // for up to Level 3, either P-192 as well as P-256 will do
2494         // 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
2495         // if remote does not SC, we should not receive P-256 data either
2496         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2497             security_possible = true;
2498         }
2499         // for Level 4, P-256 is needed
2500         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2501             security_possible = true;
2502         }
2503 #endif
2504 
2505         if (security_possible == false){
2506             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2507             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2508             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2509             return;
2510         }
2511     } else {
2512         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2513 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2514 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2515         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2516             log_info("Level 3+ required, but no input/output -> abort");
2517             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2518             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2519             return;
2520         }
2521 #endif
2522 #endif
2523     }
2524 
2525 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2526     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2527         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2528     } else {
2529         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2530     }
2531 #endif
2532 }
2533 
2534 #endif
2535 
2536 static void event_handler(uint8_t *packet, uint16_t size){
2537 
2538     uint16_t event_length = packet[1];
2539 
2540     // assert packet is complete
2541     if (size != (event_length + 2u)){
2542         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2543         return;
2544     }
2545 
2546     bd_addr_type_t addr_type;
2547     hci_con_handle_t handle;
2548     hci_connection_t * conn;
2549     int i;
2550     int create_connection_cmd;
2551 
2552 #ifdef ENABLE_CLASSIC
2553     hci_link_type_t link_type;
2554     bd_addr_t addr;
2555 #endif
2556 
2557     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2558 
2559     switch (hci_event_packet_get_type(packet)) {
2560 
2561         case HCI_EVENT_COMMAND_COMPLETE:
2562             handle_command_complete_event(packet, size);
2563             break;
2564 
2565         case HCI_EVENT_COMMAND_STATUS:
2566             // get num cmd packets - limit to 1 to reduce complexity
2567             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2568 
2569             // check command status to detected failed outgoing connections
2570             create_connection_cmd = 0;
2571 #ifdef ENABLE_CLASSIC
2572             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2573                 create_connection_cmd = 1;
2574             }
2575 #endif
2576 #ifdef ENABLE_LE_CENTRAL
2577             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2578                 create_connection_cmd = 1;
2579             }
2580 #endif
2581             if (create_connection_cmd) {
2582                 uint8_t status = hci_event_command_status_get_status(packet);
2583                 addr_type = hci_stack->outgoing_addr_type;
2584                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2585                 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);
2586 
2587                 // reset outgoing address info
2588                 memset(hci_stack->outgoing_addr, 0, 6);
2589                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2590 
2591                 // on error
2592                 if (status != ERROR_CODE_SUCCESS){
2593 #ifdef ENABLE_LE_CENTRAL
2594                     if (hci_is_le_connection_type(addr_type)){
2595                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2596                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2597                     }
2598 #endif
2599                     // error => outgoing connection failed
2600                     if (conn != NULL){
2601                         hci_handle_connection_failed(conn, status);
2602                     }
2603                 }
2604             }
2605 
2606 #ifdef ENABLE_CLASSIC
2607             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2608                 uint8_t status = hci_event_command_status_get_status(packet);
2609                 log_info("command status (inquiry), status %x", status);
2610                 if (status == ERROR_CODE_SUCCESS) {
2611                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2612                 } else {
2613                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2614                 }
2615             }
2616 #endif
2617             break;
2618 
2619         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2620             if (size < 3) return;
2621             uint16_t num_handles = packet[2];
2622             if (size != (3u + num_handles * 4u)) return;
2623             uint16_t offset = 3;
2624             for (i=0; i<num_handles;i++){
2625                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2626                 offset += 2u;
2627                 uint16_t num_packets = little_endian_read_16(packet, offset);
2628                 offset += 2u;
2629 
2630                 conn = hci_connection_for_handle(handle);
2631                 if (!conn){
2632                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2633                     continue;
2634                 }
2635 
2636                 if (conn->num_packets_sent >= num_packets){
2637                     conn->num_packets_sent -= num_packets;
2638                 } else {
2639                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2640                     conn->num_packets_sent = 0;
2641                 }
2642                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2643 
2644 #ifdef ENABLE_CLASSIC
2645                 // For SCO, we do the can_send_now_check here
2646                 hci_notify_if_sco_can_send_now();
2647 #endif
2648             }
2649             break;
2650         }
2651 
2652 #ifdef ENABLE_CLASSIC
2653         case HCI_EVENT_INQUIRY_COMPLETE:
2654             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2655                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2656                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2657                 hci_emit_event(event, sizeof(event), 1);
2658             }
2659             break;
2660         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2661             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2662                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2663             }
2664             break;
2665         case HCI_EVENT_CONNECTION_REQUEST:
2666             reverse_bd_addr(&packet[2], addr);
2667             link_type = (hci_link_type_t) packet[11];
2668 
2669             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2670             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2671                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2672                 bd_addr_copy(hci_stack->decline_addr, addr);
2673                 break;
2674             }
2675 
2676             if (hci_stack->gap_classic_accept_callback != NULL){
2677                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2678                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2679                     bd_addr_copy(hci_stack->decline_addr, addr);
2680                     break;
2681                 }
2682             }
2683 
2684             // TODO: eval COD 8-10
2685             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2686             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2687             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2688             if (!conn) {
2689                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2690             }
2691             if (!conn) {
2692                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2693                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2694                 bd_addr_copy(hci_stack->decline_addr, addr);
2695                 break;
2696             }
2697             conn->role  = HCI_ROLE_SLAVE;
2698             conn->state = RECEIVED_CONNECTION_REQUEST;
2699             // store info about eSCO
2700             if (link_type == HCI_LINK_TYPE_ESCO){
2701                 conn->remote_supported_features[0] |= 1;
2702             }
2703             hci_run();
2704             break;
2705 
2706         case HCI_EVENT_CONNECTION_COMPLETE:
2707             // Connection management
2708             reverse_bd_addr(&packet[5], addr);
2709             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2710             addr_type = BD_ADDR_TYPE_ACL;
2711             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2712             if (conn) {
2713                 if (!packet[2]){
2714                     conn->state = OPEN;
2715                     conn->con_handle = little_endian_read_16(packet, 3);
2716 
2717                     // queue set supervision timeout if we're master
2718                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2719                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2720                     }
2721 
2722                     // restart timer
2723                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2724                     btstack_run_loop_add_timer(&conn->timeout);
2725 
2726                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2727 
2728                     hci_emit_nr_connections_changed();
2729                 } else {
2730                     // connection failed
2731                     hci_handle_connection_failed(conn, packet[2]);
2732                 }
2733             }
2734             break;
2735 
2736         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2737             reverse_bd_addr(&packet[5], addr);
2738             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2739             if (packet[2]){
2740                 // connection failed
2741                 break;
2742             }
2743             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2744             if (!conn) {
2745                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2746             }
2747             if (!conn) {
2748                 break;
2749             }
2750             conn->state = OPEN;
2751             conn->con_handle = little_endian_read_16(packet, 3);
2752 
2753 #ifdef ENABLE_SCO_OVER_HCI
2754             // update SCO
2755             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2756                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2757             }
2758             // trigger can send now
2759             if (hci_have_usb_transport()){
2760                 hci_stack->sco_can_send_now = true;
2761             }
2762 #endif
2763 #ifdef HAVE_SCO_TRANSPORT
2764             // configure sco transport
2765             if (hci_stack->sco_transport != NULL){
2766                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2767                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2768             }
2769 #endif
2770             break;
2771 
2772         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2773             handle = little_endian_read_16(packet, 3);
2774             conn = hci_connection_for_handle(handle);
2775             if (!conn) break;
2776             if (!packet[2]){
2777                 const uint8_t * features = &packet[5];
2778                 hci_handle_remote_features_page_0(conn, features);
2779 
2780                 // read extended features if possible
2781                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2782                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2783                     break;
2784                 }
2785             }
2786             hci_handle_remote_features_received(conn);
2787             break;
2788 
2789         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2790             handle = little_endian_read_16(packet, 3);
2791             conn = hci_connection_for_handle(handle);
2792             if (!conn) break;
2793             // status = ok, page = 1
2794             if (!packet[2]) {
2795                 uint8_t page_number = packet[5];
2796                 uint8_t maximum_page_number = packet[6];
2797                 const uint8_t * features = &packet[7];
2798                 bool done = false;
2799                 switch (page_number){
2800                     case 1:
2801                         hci_handle_remote_features_page_1(conn, features);
2802                         if (maximum_page_number >= 2){
2803                             // get Secure Connections (Controller) from Page 2 if available
2804                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2805                         } else {
2806                             // otherwise, assume SC (Controller) == SC (Host)
2807                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2808                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2809                             }
2810                             done = true;
2811                         }
2812                         break;
2813                     case 2:
2814                         hci_handle_remote_features_page_2(conn, features);
2815                         done = true;
2816                         break;
2817                     default:
2818                         break;
2819                 }
2820                 if (!done) break;
2821             }
2822             hci_handle_remote_features_received(conn);
2823             break;
2824 
2825         case HCI_EVENT_LINK_KEY_REQUEST:
2826 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2827             hci_event_link_key_request_get_bd_addr(packet, addr);
2828             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2829             if (!conn) break;
2830 
2831             // lookup link key in db if not cached
2832             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2833                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2834             }
2835 
2836             // response sent by hci_run()
2837             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2838 #endif
2839             break;
2840 
2841         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2842             hci_event_link_key_request_get_bd_addr(packet, addr);
2843             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2844             if (!conn) break;
2845 
2846             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2847 
2848             // CVE-2020-26555: ignore NULL link key
2849             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2850             if (btstack_is_null(&packet[8], 16)) break;
2851 
2852             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2853             // Change Connection Encryption keeps link key type
2854             if (link_key_type != CHANGED_COMBINATION_KEY){
2855                 conn->link_key_type = link_key_type;
2856             }
2857 
2858             // cache link key. link keys stored in little-endian format for legacy reasons
2859             memcpy(&conn->link_key, &packet[8], 16);
2860 
2861             // only store link key:
2862             // - if bondable enabled
2863             if (hci_stack->bondable == false) break;
2864             // - if security level sufficient
2865             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2866             // - for SSP, also check if remote side requested bonding as well
2867             if (conn->link_key_type != COMBINATION_KEY){
2868                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2869                 if (!remote_bonding){
2870                     break;
2871                 }
2872             }
2873             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2874             break;
2875         }
2876 
2877         case HCI_EVENT_PIN_CODE_REQUEST:
2878             hci_event_pin_code_request_get_bd_addr(packet, addr);
2879             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2880             if (!conn) break;
2881 
2882             hci_pairing_started(conn, false);
2883             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2884             if (!hci_stack->bondable ){
2885                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2886                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2887                 hci_run();
2888                 return;
2889             }
2890             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2891             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2892                 log_info("Level 4 required, but SC not supported -> abort");
2893                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2894                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2895                 hci_run();
2896                 return;
2897             }
2898             break;
2899 
2900         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2901             hci_event_io_capability_response_get_bd_addr(packet, addr);
2902             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2903             if (!conn) break;
2904 
2905             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2906             hci_pairing_started(conn, true);
2907             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2908             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2909 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2910             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2911 #endif
2912             break;
2913 
2914         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2915             hci_event_io_capability_response_get_bd_addr(packet, addr);
2916             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2917             if (!conn) break;
2918 
2919             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2920             hci_connection_timestamp(conn);
2921             hci_pairing_started(conn, true);
2922             break;
2923 
2924 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2925         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2926             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2927             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2928             if (!conn) break;
2929 
2930             hci_connection_timestamp(conn);
2931 
2932             hci_pairing_started(conn, true);
2933 
2934             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2935             break;
2936 #endif
2937 
2938         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2939             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2940             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2941             if (!conn) break;
2942             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2943                 if (hci_stack->ssp_auto_accept){
2944                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2945                 };
2946             } else {
2947                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2948                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2949                 // don't forward event to app
2950                 hci_run();
2951                 return;
2952             }
2953             break;
2954 
2955         case HCI_EVENT_USER_PASSKEY_REQUEST:
2956             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2957             if (hci_stack->ssp_auto_accept){
2958                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2959             };
2960             break;
2961 
2962         case HCI_EVENT_MODE_CHANGE:
2963             handle = hci_event_mode_change_get_handle(packet);
2964             conn = hci_connection_for_handle(handle);
2965             if (!conn) break;
2966             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2967             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2968             break;
2969 #endif
2970 
2971         case HCI_EVENT_ENCRYPTION_CHANGE:
2972             handle = hci_event_encryption_change_get_connection_handle(packet);
2973             conn = hci_connection_for_handle(handle);
2974             if (!conn) break;
2975             if (hci_event_encryption_change_get_status(packet) == 0u) {
2976                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2977                 if (encryption_enabled){
2978                     if (hci_is_le_connection(conn)){
2979                         // For LE, we accept connection as encrypted
2980                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2981                     }
2982 #ifdef ENABLE_CLASSIC
2983                     else {
2984 
2985                         // dedicated bonding: send result and disconnect
2986                         if (conn->bonding_flags & BONDING_DEDICATED){
2987                             conn->bonding_flags &= ~BONDING_DEDICATED;
2988                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2989                             conn->bonding_status = packet[2];
2990                             break;
2991                         }
2992 
2993                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2994                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2995                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2996                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2997                             log_info("SC during pairing, but only E0 now -> abort");
2998                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2999                             break;
3000                         }
3001 
3002                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3003                         if (connected_uses_aes_ccm){
3004                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3005                         }
3006 
3007 #ifdef ENABLE_TESTING_SUPPORT
3008                         // work around for issue with PTS dongle
3009                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3010 #endif
3011 
3012                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3013                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3014                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3015                         } else {
3016                             // if not, pretend everything is perfect
3017                             hci_handle_read_encryption_key_size_complete(conn, 16);
3018                         }
3019                     }
3020 #endif
3021                 } else {
3022                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3023                 }
3024             }
3025 
3026             break;
3027 
3028 #ifdef ENABLE_CLASSIC
3029         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3030             handle = hci_event_authentication_complete_get_connection_handle(packet);
3031             conn = hci_connection_for_handle(handle);
3032             if (!conn) break;
3033 
3034             // clear authentication active flag
3035             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3036             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3037 
3038             // authenticated only if auth status == 0
3039             if (hci_event_authentication_complete_get_status(packet) == 0){
3040                 // authenticated
3041                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3042 
3043                 // If not already encrypted, start encryption
3044                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3045                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3046                     break;
3047                 }
3048             }
3049 
3050             // emit updated security level
3051             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3052             break;
3053 
3054         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3055             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3056             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3057             if (!conn) break;
3058 
3059             // treat successfully paired connection as authenticated
3060             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3061                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3062             }
3063 
3064             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3065             break;
3066 #endif
3067 
3068         // HCI_EVENT_DISCONNECTION_COMPLETE
3069         // has been split, to first notify stack before shutting connection down
3070         // see end of function, too.
3071         case HCI_EVENT_DISCONNECTION_COMPLETE:
3072             if (packet[2]) break;   // status != 0
3073             handle = little_endian_read_16(packet, 3);
3074             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3075             if (hci_stack->acl_fragmentation_total_size > 0u) {
3076                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3077                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3078                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3079                     hci_stack->acl_fragmentation_total_size = 0;
3080                     hci_stack->acl_fragmentation_pos = 0;
3081                     if (release_buffer){
3082                         hci_release_packet_buffer();
3083                     }
3084                 }
3085             }
3086 
3087             conn = hci_connection_for_handle(handle);
3088             if (!conn) break;
3089 #ifdef ENABLE_CLASSIC
3090             // pairing failed if it was ongoing
3091             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3092 #endif
3093 
3094             // emit dedicatd bonding event
3095             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3096                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3097             }
3098 
3099             // mark connection for shutdown, stop timers, reset state
3100             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3101             hci_connection_stop_timer(conn);
3102             hci_connection_init(conn);
3103 
3104 #ifdef ENABLE_BLE
3105 #ifdef ENABLE_LE_PERIPHERAL
3106             // re-enable advertisements for le connections if active
3107             if (hci_is_le_connection(conn)){
3108                 hci_update_advertisements_enabled_for_current_roles();
3109             }
3110 #endif
3111 #endif
3112             break;
3113 
3114         case HCI_EVENT_HARDWARE_ERROR:
3115             log_error("Hardware Error: 0x%02x", packet[2]);
3116             if (hci_stack->hardware_error_callback){
3117                 (*hci_stack->hardware_error_callback)(packet[2]);
3118             } else {
3119                 // if no special requests, just reboot stack
3120                 hci_power_control_off();
3121                 hci_power_control_on();
3122             }
3123             break;
3124 
3125 #ifdef ENABLE_CLASSIC
3126         case HCI_EVENT_ROLE_CHANGE:
3127             if (packet[2]) break;   // status != 0
3128             reverse_bd_addr(&packet[3], addr);
3129             addr_type = BD_ADDR_TYPE_ACL;
3130             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3131             if (!conn) break;
3132             conn->role = packet[9];
3133             break;
3134 #endif
3135 
3136         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3137             // release packet buffer only for asynchronous transport and if there are not further fragements
3138             if (hci_transport_synchronous()) {
3139                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3140                 return; // instead of break: to avoid re-entering hci_run()
3141             }
3142             hci_stack->acl_fragmentation_tx_active = 0;
3143             if (hci_stack->acl_fragmentation_total_size) break;
3144             hci_release_packet_buffer();
3145 
3146             // L2CAP receives this event via the hci_emit_event below
3147 
3148 #ifdef ENABLE_CLASSIC
3149             // For SCO, we do the can_send_now_check here
3150             hci_notify_if_sco_can_send_now();
3151 #endif
3152             break;
3153 
3154 #ifdef ENABLE_CLASSIC
3155         case HCI_EVENT_SCO_CAN_SEND_NOW:
3156             // For SCO, we do the can_send_now_check here
3157             hci_stack->sco_can_send_now = true;
3158             hci_notify_if_sco_can_send_now();
3159             return;
3160 
3161         // explode inquriy results for easier consumption
3162         case HCI_EVENT_INQUIRY_RESULT:
3163         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3164         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3165             gap_inquiry_explode(packet, size);
3166             break;
3167 #endif
3168 
3169 #ifdef ENABLE_BLE
3170         case HCI_EVENT_LE_META:
3171             switch (packet[2]){
3172 #ifdef ENABLE_LE_CENTRAL
3173                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3174                     // log_info("advertising report received");
3175                     if (!hci_stack->le_scanning_enabled) break;
3176                     le_handle_advertisement_report(packet, size);
3177                     break;
3178 #endif
3179                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3180 					event_handle_le_connection_complete(packet);
3181                     break;
3182 
3183                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3184                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3185                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3186                     conn = hci_connection_for_handle(handle);
3187                     if (!conn) break;
3188                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3189                     break;
3190 
3191                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3192                     // connection
3193                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3194                     conn = hci_connection_for_handle(handle);
3195                     if (conn) {
3196                         // read arguments
3197                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3198                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3199                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3200                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3201 
3202                         // validate against current connection parameter range
3203                         le_connection_parameter_range_t existing_range;
3204                         gap_get_connection_parameter_range(&existing_range);
3205                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3206                         if (update_parameter){
3207                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3208                             conn->le_conn_interval_min = le_conn_interval_min;
3209                             conn->le_conn_interval_max = le_conn_interval_max;
3210                             conn->le_conn_latency = le_conn_latency;
3211                             conn->le_supervision_timeout = le_supervision_timeout;
3212                         } else {
3213                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3214                         }
3215                     }
3216                     break;
3217 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3218                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3219                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3220                     conn = hci_connection_for_handle(handle);
3221                     if (conn) {
3222                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3223                     }
3224                     break;
3225 #endif
3226                 default:
3227                     break;
3228             }
3229             break;
3230 #endif
3231         case HCI_EVENT_VENDOR_SPECIFIC:
3232             // Vendor specific commands often create vendor specific event instead of num completed packets
3233             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3234             switch (hci_stack->manufacturer){
3235                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3236                     hci_stack->num_cmd_packets = 1;
3237                     break;
3238                 default:
3239                     break;
3240             }
3241             break;
3242         default:
3243             break;
3244     }
3245 
3246     handle_event_for_current_stack_state(packet, size);
3247 
3248     // notify upper stack
3249 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3250 
3251     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3252     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3253 		handle = little_endian_read_16(packet, 3);
3254 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3255 		// discard connection if app did not trigger a reconnect in the event handler
3256 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3257 			hci_shutdown_connection(aConn);
3258 		}
3259     }
3260 
3261 	// execute main loop
3262 	hci_run();
3263 }
3264 
3265 #ifdef ENABLE_CLASSIC
3266 
3267 #ifdef ENABLE_SCO_OVER_HCI
3268 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3269 static void sco_schedule_tx(hci_connection_t * conn);
3270 
3271 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3272     log_debug("SCO TX Timeout");
3273     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3274     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3275     if (!conn) return;
3276 
3277     // trigger send
3278     conn->sco_tx_ready = 1;
3279     // extra packet if CVSD but SCO buffer is too short
3280     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3281         conn->sco_tx_ready++;
3282     }
3283     hci_notify_if_sco_can_send_now();
3284 }
3285 
3286 
3287 #define SCO_TX_AFTER_RX_MS (6)
3288 
3289 static void sco_schedule_tx(hci_connection_t * conn){
3290 
3291     uint32_t now = btstack_run_loop_get_time_ms();
3292     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3293     int time_delta_ms = sco_tx_ms - now;
3294 
3295     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3296 
3297     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3298     btstack_run_loop_remove_timer(timer);
3299     btstack_run_loop_set_timer(timer, time_delta_ms);
3300     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3301     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3302     btstack_run_loop_add_timer(timer);
3303 }
3304 #endif
3305 
3306 static void sco_handler(uint8_t * packet, uint16_t size){
3307     // lookup connection struct
3308     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3309     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3310     if (!conn) return;
3311 
3312 #ifdef ENABLE_SCO_OVER_HCI
3313     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3314     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3315         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3316             packet[2] = 0x3c;
3317             memmove(&packet[3], &packet[23], 63);
3318             size = 63;
3319         }
3320     }
3321 
3322     if (hci_have_usb_transport()){
3323         // Nothing to do
3324     } else {
3325         // 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);
3326         if (hci_stack->synchronous_flow_control_enabled == 0){
3327             uint32_t now = btstack_run_loop_get_time_ms();
3328 
3329             if (!conn->sco_rx_valid){
3330                 // ignore first 10 packets
3331                 conn->sco_rx_count++;
3332                 // log_debug("sco rx count %u", conn->sco_rx_count);
3333                 if (conn->sco_rx_count == 10) {
3334                     // use first timestamp as is and pretent it just started
3335                     conn->sco_rx_ms = now;
3336                     conn->sco_rx_valid = 1;
3337                     conn->sco_rx_count = 0;
3338                     sco_schedule_tx(conn);
3339                 }
3340             } else {
3341                 // track expected arrival timme
3342                 conn->sco_rx_count++;
3343                 conn->sco_rx_ms += 7;
3344                 int delta = (int32_t) (now - conn->sco_rx_ms);
3345                 if (delta > 0){
3346                     conn->sco_rx_ms++;
3347                 }
3348                 // log_debug("sco rx %u", conn->sco_rx_ms);
3349                 sco_schedule_tx(conn);
3350             }
3351         }
3352     }
3353 #endif
3354 
3355     // deliver to app
3356     if (hci_stack->sco_packet_handler) {
3357         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3358     }
3359 
3360 #ifdef HAVE_SCO_TRANSPORT
3361     // We can send one packet for each received packet
3362     conn->sco_tx_ready++;
3363     hci_notify_if_sco_can_send_now();
3364 #endif
3365 
3366 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3367     conn->num_packets_completed++;
3368     hci_stack->host_completed_packets = 1;
3369     hci_run();
3370 #endif
3371 }
3372 #endif
3373 
3374 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3375     hci_dump_packet(packet_type, 1, packet, size);
3376     switch (packet_type) {
3377         case HCI_EVENT_PACKET:
3378             event_handler(packet, size);
3379             break;
3380         case HCI_ACL_DATA_PACKET:
3381             acl_handler(packet, size);
3382             break;
3383 #ifdef ENABLE_CLASSIC
3384         case HCI_SCO_DATA_PACKET:
3385             sco_handler(packet, size);
3386             break;
3387 #endif
3388         default:
3389             break;
3390     }
3391 }
3392 
3393 /**
3394  * @brief Add event packet handler.
3395  */
3396 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3397     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3398 }
3399 
3400 /**
3401  * @brief Remove event packet handler.
3402  */
3403 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3404     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3405 }
3406 
3407 /** Register HCI packet handlers */
3408 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3409     hci_stack->acl_packet_handler = handler;
3410 }
3411 
3412 #ifdef ENABLE_CLASSIC
3413 /**
3414  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3415  */
3416 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3417     hci_stack->sco_packet_handler = handler;
3418 }
3419 #endif
3420 
3421 static void hci_state_reset(void){
3422     // no connections yet
3423     hci_stack->connections = NULL;
3424 
3425     // keep discoverable/connectable as this has been requested by the client(s)
3426     // hci_stack->discoverable = 0;
3427     // hci_stack->connectable = 0;
3428     // hci_stack->bondable = 1;
3429     // hci_stack->own_addr_type = 0;
3430 
3431     // buffer is free
3432     hci_stack->hci_packet_buffer_reserved = false;
3433 
3434     // no pending cmds
3435     hci_stack->decline_reason = 0;
3436 
3437     hci_stack->secure_connections_active = false;
3438 
3439 #ifdef ENABLE_CLASSIC
3440     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3441     hci_stack->gap_tasks =
3442             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3443             GAP_TASK_SET_CLASS_OF_DEVICE |
3444             GAP_TASK_SET_LOCAL_NAME |
3445             GAP_TASK_SET_EIR_DATA |
3446             GAP_TASK_WRITE_SCAN_ENABLE;
3447 #endif
3448 
3449 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3450     hci_stack->classic_read_local_oob_data = false;
3451     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3452 #endif
3453 
3454     // LE
3455 #ifdef ENABLE_BLE
3456     memset(hci_stack->le_random_address, 0, 6);
3457     hci_stack->le_random_address_set = 0;
3458 #endif
3459 #ifdef ENABLE_LE_CENTRAL
3460     hci_stack->le_scanning_active  = false;
3461     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3462     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3463     hci_stack->le_whitelist_capacity = 0;
3464 #endif
3465 #ifdef ENABLE_LE_PERIPHERAL
3466     hci_stack->le_advertisements_active = false;
3467     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3468         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3469     }
3470     if (hci_stack->le_advertisements_data != NULL){
3471         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3472     }
3473 #endif
3474 }
3475 
3476 #ifdef ENABLE_CLASSIC
3477 /**
3478  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3479  */
3480 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3481     // store and open remote device db
3482     hci_stack->link_key_db = link_key_db;
3483     if (hci_stack->link_key_db) {
3484         hci_stack->link_key_db->open();
3485     }
3486 }
3487 #endif
3488 
3489 void hci_init(const hci_transport_t *transport, const void *config){
3490 
3491 #ifdef HAVE_MALLOC
3492     if (!hci_stack) {
3493         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3494     }
3495 #else
3496     hci_stack = &hci_stack_static;
3497 #endif
3498     memset(hci_stack, 0, sizeof(hci_stack_t));
3499 
3500     // reference to use transport layer implementation
3501     hci_stack->hci_transport = transport;
3502 
3503     // reference to used config
3504     hci_stack->config = config;
3505 
3506     // setup pointer for outgoing packet buffer
3507     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3508 
3509     // max acl payload size defined in config.h
3510     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3511 
3512     // register packet handlers with transport
3513     transport->register_packet_handler(&packet_handler);
3514 
3515     hci_stack->state = HCI_STATE_OFF;
3516 
3517     // class of device
3518     hci_stack->class_of_device = 0x007a020c; // Smartphone
3519 
3520     // bondable by default
3521     hci_stack->bondable = 1;
3522 
3523 #ifdef ENABLE_CLASSIC
3524     // classic name
3525     hci_stack->local_name = default_classic_name;
3526 
3527     // Master slave policy
3528     hci_stack->master_slave_policy = 1;
3529 
3530     // Allow Role Switch
3531     hci_stack->allow_role_switch = 1;
3532 
3533     // Default / minimum security level = 2
3534     hci_stack->gap_security_level = LEVEL_2;
3535 
3536     // Default Security Mode 4
3537     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3538 
3539     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3540     hci_stack->gap_required_encyrption_key_size = 7;
3541 
3542     // Link Supervision Timeout
3543     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3544 
3545 #endif
3546 
3547     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3548     hci_stack->ssp_enable = 1;
3549     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3550     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3551     hci_stack->ssp_auto_accept = 1;
3552 
3553     // Secure Connections: enable (requires support from Controller)
3554     hci_stack->secure_connections_enable = true;
3555 
3556     // voice setting - signed 16 bit pcm data with CVSD over the air
3557     hci_stack->sco_voice_setting = 0x60;
3558 
3559 #ifdef ENABLE_LE_CENTRAL
3560     // connection parameter to use for outgoing connections
3561     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3562     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3563     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3564     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3565     hci_stack->le_connection_latency      = 4;         // 4
3566     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3567     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3568     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3569 
3570     // default LE Scanning
3571     hci_stack->le_scan_type     =   0x1; // active
3572     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3573     hci_stack->le_scan_window   =  0x30; //  30 ms
3574 #endif
3575 
3576 #ifdef ENABLE_LE_PERIPHERAL
3577     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3578 #endif
3579 
3580     // connection parameter range used to answer connection parameter update requests in l2cap
3581     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3582     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3583     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3584     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3585     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3586     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3587 
3588     hci_state_reset();
3589 }
3590 
3591 void hci_deinit(void){
3592 #ifdef HAVE_MALLOC
3593     if (hci_stack) {
3594         free(hci_stack);
3595     }
3596 #endif
3597     hci_stack = NULL;
3598 
3599 #ifdef ENABLE_CLASSIC
3600     disable_l2cap_timeouts = 0;
3601 #endif
3602 }
3603 
3604 /**
3605  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3606  */
3607 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3608     hci_stack->chipset = chipset_driver;
3609 
3610     // reset chipset driver - init is also called on power_up
3611     if (hci_stack->chipset && hci_stack->chipset->init){
3612         hci_stack->chipset->init(hci_stack->config);
3613     }
3614 }
3615 
3616 /**
3617  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3618  */
3619 void hci_set_control(const btstack_control_t *hardware_control){
3620     // references to used control implementation
3621     hci_stack->control = hardware_control;
3622     // init with transport config
3623     hardware_control->init(hci_stack->config);
3624 }
3625 
3626 void hci_close(void){
3627 
3628 #ifdef ENABLE_CLASSIC
3629     // close remote device db
3630     if (hci_stack->link_key_db) {
3631         hci_stack->link_key_db->close();
3632     }
3633 #endif
3634 
3635     btstack_linked_list_iterator_t lit;
3636     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3637     while (btstack_linked_list_iterator_has_next(&lit)){
3638         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3639         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3640         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3641         hci_shutdown_connection(connection);
3642     }
3643 
3644     hci_power_control(HCI_POWER_OFF);
3645 
3646 #ifdef HAVE_MALLOC
3647     free(hci_stack);
3648 #endif
3649     hci_stack = NULL;
3650 }
3651 
3652 #ifdef HAVE_SCO_TRANSPORT
3653 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3654     hci_stack->sco_transport = sco_transport;
3655     sco_transport->register_packet_handler(&packet_handler);
3656 }
3657 #endif
3658 
3659 #ifdef ENABLE_CLASSIC
3660 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3661     // validate ranage and set
3662     if (encryption_key_size < 7)  return;
3663     if (encryption_key_size > 16) return;
3664     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3665 }
3666 
3667 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3668     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3669         hci_stack->gap_security_mode = security_mode;
3670         return ERROR_CODE_SUCCESS;
3671     } else {
3672         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3673     }
3674 }
3675 
3676 gap_security_mode_t gap_get_security_mode(void){
3677     return hci_stack->gap_security_mode;
3678 }
3679 
3680 void gap_set_security_level(gap_security_level_t security_level){
3681     hci_stack->gap_security_level = security_level;
3682 }
3683 
3684 gap_security_level_t gap_get_security_level(void){
3685     if (hci_stack->gap_secure_connections_only_mode){
3686         return LEVEL_4;
3687     }
3688     return hci_stack->gap_security_level;
3689 }
3690 
3691 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3692     hci_stack->gap_minimal_service_security_level = security_level;
3693 }
3694 
3695 void gap_set_secure_connections_only_mode(bool enable){
3696     hci_stack->gap_secure_connections_only_mode = enable;
3697 }
3698 
3699 bool gap_get_secure_connections_only_mode(void){
3700     return hci_stack->gap_secure_connections_only_mode;
3701 }
3702 #endif
3703 
3704 #ifdef ENABLE_CLASSIC
3705 void gap_set_class_of_device(uint32_t class_of_device){
3706     hci_stack->class_of_device = class_of_device;
3707     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3708     hci_run();
3709 }
3710 
3711 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3712     hci_stack->default_link_policy_settings = default_link_policy_settings;
3713     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3714     hci_run();
3715 }
3716 
3717 void gap_set_allow_role_switch(bool allow_role_switch){
3718     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3719 }
3720 
3721 uint8_t hci_get_allow_role_switch(void){
3722     return  hci_stack->allow_role_switch;
3723 }
3724 
3725 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3726     hci_stack->link_supervision_timeout = link_supervision_timeout;
3727 }
3728 
3729 void hci_disable_l2cap_timeout_check(void){
3730     disable_l2cap_timeouts = 1;
3731 }
3732 #endif
3733 
3734 #ifndef HAVE_HOST_CONTROLLER_API
3735 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3736 void hci_set_bd_addr(bd_addr_t addr){
3737     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3738     hci_stack->custom_bd_addr_set = 1;
3739 }
3740 #endif
3741 
3742 // State-Module-Driver overview
3743 // state                    module  low-level
3744 // HCI_STATE_OFF             off      close
3745 // HCI_STATE_INITIALIZING,   on       open
3746 // HCI_STATE_WORKING,        on       open
3747 // HCI_STATE_HALTING,        on       open
3748 // HCI_STATE_SLEEPING,    off/sleep   close
3749 // HCI_STATE_FALLING_ASLEEP  on       open
3750 
3751 static int hci_power_control_on(void){
3752 
3753     // power on
3754     int err = 0;
3755     if (hci_stack->control && hci_stack->control->on){
3756         err = (*hci_stack->control->on)();
3757     }
3758     if (err){
3759         log_error( "POWER_ON failed");
3760         hci_emit_hci_open_failed();
3761         return err;
3762     }
3763 
3764     // int chipset driver
3765     if (hci_stack->chipset && hci_stack->chipset->init){
3766         hci_stack->chipset->init(hci_stack->config);
3767     }
3768 
3769     // init transport
3770     if (hci_stack->hci_transport->init){
3771         hci_stack->hci_transport->init(hci_stack->config);
3772     }
3773 
3774     // open transport
3775     err = hci_stack->hci_transport->open();
3776     if (err){
3777         log_error( "HCI_INIT failed, turning Bluetooth off again");
3778         if (hci_stack->control && hci_stack->control->off){
3779             (*hci_stack->control->off)();
3780         }
3781         hci_emit_hci_open_failed();
3782         return err;
3783     }
3784     return 0;
3785 }
3786 
3787 static void hci_power_control_off(void){
3788 
3789     log_info("hci_power_control_off");
3790 
3791     // close low-level device
3792     hci_stack->hci_transport->close();
3793 
3794     log_info("hci_power_control_off - hci_transport closed");
3795 
3796     // power off
3797     if (hci_stack->control && hci_stack->control->off){
3798         (*hci_stack->control->off)();
3799     }
3800 
3801     log_info("hci_power_control_off - control closed");
3802 
3803     hci_stack->state = HCI_STATE_OFF;
3804 }
3805 
3806 static void hci_power_control_sleep(void){
3807 
3808     log_info("hci_power_control_sleep");
3809 
3810 #if 0
3811     // don't close serial port during sleep
3812 
3813     // close low-level device
3814     hci_stack->hci_transport->close(hci_stack->config);
3815 #endif
3816 
3817     // sleep mode
3818     if (hci_stack->control && hci_stack->control->sleep){
3819         (*hci_stack->control->sleep)();
3820     }
3821 
3822     hci_stack->state = HCI_STATE_SLEEPING;
3823 }
3824 
3825 static int hci_power_control_wake(void){
3826 
3827     log_info("hci_power_control_wake");
3828 
3829     // wake on
3830     if (hci_stack->control && hci_stack->control->wake){
3831         (*hci_stack->control->wake)();
3832     }
3833 
3834 #if 0
3835     // open low-level device
3836     int err = hci_stack->hci_transport->open(hci_stack->config);
3837     if (err){
3838         log_error( "HCI_INIT failed, turning Bluetooth off again");
3839         if (hci_stack->control && hci_stack->control->off){
3840             (*hci_stack->control->off)();
3841         }
3842         hci_emit_hci_open_failed();
3843         return err;
3844     }
3845 #endif
3846 
3847     return 0;
3848 }
3849 
3850 static void hci_power_transition_to_initializing(void){
3851     // set up state machine
3852     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3853     hci_stack->hci_packet_buffer_reserved = false;
3854     hci_stack->state = HCI_STATE_INITIALIZING;
3855     hci_stack->substate = HCI_INIT_SEND_RESET;
3856 }
3857 
3858 // returns error
3859 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3860     int err;
3861     switch (power_mode){
3862         case HCI_POWER_ON:
3863             err = hci_power_control_on();
3864             if (err != 0) {
3865                 log_error("hci_power_control_on() error %d", err);
3866                 return err;
3867             }
3868             hci_power_transition_to_initializing();
3869             break;
3870         case HCI_POWER_OFF:
3871             // do nothing
3872             break;
3873         case HCI_POWER_SLEEP:
3874             // do nothing (with SLEEP == OFF)
3875             break;
3876         default:
3877             btstack_assert(false);
3878             break;
3879     }
3880     return ERROR_CODE_SUCCESS;
3881 }
3882 
3883 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3884     switch (power_mode){
3885         case HCI_POWER_ON:
3886             // do nothing
3887             break;
3888         case HCI_POWER_OFF:
3889             // no connections yet, just turn it off
3890             hci_power_control_off();
3891             break;
3892         case HCI_POWER_SLEEP:
3893             // no connections yet, just turn it off
3894             hci_power_control_sleep();
3895             break;
3896         default:
3897             btstack_assert(false);
3898             break;
3899     }
3900     return ERROR_CODE_SUCCESS;
3901 }
3902 
3903 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3904     switch (power_mode){
3905         case HCI_POWER_ON:
3906             // do nothing
3907             break;
3908         case HCI_POWER_OFF:
3909             // see hci_run
3910             hci_stack->state = HCI_STATE_HALTING;
3911             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3912             break;
3913         case HCI_POWER_SLEEP:
3914             // see hci_run
3915             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3916             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3917             break;
3918         default:
3919             btstack_assert(false);
3920             break;
3921     }
3922     return ERROR_CODE_SUCCESS;
3923 }
3924 
3925 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3926     switch (power_mode){
3927         case HCI_POWER_ON:
3928             hci_power_transition_to_initializing();
3929             break;
3930         case HCI_POWER_OFF:
3931             // do nothing
3932             break;
3933         case HCI_POWER_SLEEP:
3934             // see hci_run
3935             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3936             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3937             break;
3938         default:
3939             btstack_assert(false);
3940             break;
3941     }
3942     return ERROR_CODE_SUCCESS;
3943 }
3944 
3945 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3946     switch (power_mode){
3947         case HCI_POWER_ON:
3948             hci_power_transition_to_initializing();
3949             break;
3950         case HCI_POWER_OFF:
3951             // see hci_run
3952             hci_stack->state = HCI_STATE_HALTING;
3953             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3954             break;
3955         case HCI_POWER_SLEEP:
3956             // do nothing
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_sleeping(HCI_POWER_MODE power_mode) {
3966     int err;
3967     switch (power_mode){
3968         case HCI_POWER_ON:
3969             err = hci_power_control_wake();
3970             if (err) return err;
3971             hci_power_transition_to_initializing();
3972             break;
3973         case HCI_POWER_OFF:
3974             hci_stack->state = HCI_STATE_HALTING;
3975             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3976             break;
3977         case HCI_POWER_SLEEP:
3978             // do nothing
3979             break;
3980         default:
3981             btstack_assert(false);
3982             break;
3983     }
3984     return ERROR_CODE_SUCCESS;
3985 }
3986 
3987 int hci_power_control(HCI_POWER_MODE power_mode){
3988     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3989     int err = 0;
3990     switch (hci_stack->state){
3991         case HCI_STATE_OFF:
3992             err = hci_power_control_state_off(power_mode);
3993             break;
3994         case HCI_STATE_INITIALIZING:
3995             err = hci_power_control_state_initializing(power_mode);
3996             break;
3997         case HCI_STATE_WORKING:
3998             err = hci_power_control_state_working(power_mode);
3999             break;
4000         case HCI_STATE_HALTING:
4001             err = hci_power_control_state_halting(power_mode);
4002             break;
4003         case HCI_STATE_FALLING_ASLEEP:
4004             err = hci_power_control_state_falling_asleep(power_mode);
4005             break;
4006         case HCI_STATE_SLEEPING:
4007             err = hci_power_control_state_sleeping(power_mode);
4008             break;
4009         default:
4010             btstack_assert(false);
4011             break;
4012     }
4013     if (err != 0){
4014         return err;
4015     }
4016 
4017     // create internal event
4018 	hci_emit_state();
4019 
4020 	// trigger next/first action
4021 	hci_run();
4022 
4023     return 0;
4024 }
4025 
4026 
4027 #ifdef ENABLE_CLASSIC
4028 
4029 static void hci_update_scan_enable(void){
4030     // 2 = page scan, 1 = inq scan
4031     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4032     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4033     hci_run();
4034 }
4035 
4036 void gap_discoverable_control(uint8_t enable){
4037     if (enable) enable = 1; // normalize argument
4038 
4039     if (hci_stack->discoverable == enable){
4040         hci_emit_discoverable_enabled(hci_stack->discoverable);
4041         return;
4042     }
4043 
4044     hci_stack->discoverable = enable;
4045     hci_update_scan_enable();
4046 }
4047 
4048 void gap_connectable_control(uint8_t enable){
4049     if (enable) enable = 1; // normalize argument
4050 
4051     // don't emit event
4052     if (hci_stack->connectable == enable) return;
4053 
4054     hci_stack->connectable = enable;
4055     hci_update_scan_enable();
4056 }
4057 #endif
4058 
4059 void gap_local_bd_addr(bd_addr_t address_buffer){
4060     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4061 }
4062 
4063 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4064 static void hci_host_num_completed_packets(void){
4065 
4066     // create packet manually as arrays are not supported and num_commands should not get reduced
4067     hci_reserve_packet_buffer();
4068     uint8_t * packet = hci_get_outgoing_packet_buffer();
4069 
4070     uint16_t size = 0;
4071     uint16_t num_handles = 0;
4072     packet[size++] = 0x35;
4073     packet[size++] = 0x0c;
4074     size++;  // skip param len
4075     size++;  // skip num handles
4076 
4077     // add { handle, packets } entries
4078     btstack_linked_item_t * it;
4079     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4080         hci_connection_t * connection = (hci_connection_t *) it;
4081         if (connection->num_packets_completed){
4082             little_endian_store_16(packet, size, connection->con_handle);
4083             size += 2;
4084             little_endian_store_16(packet, size, connection->num_packets_completed);
4085             size += 2;
4086             //
4087             num_handles++;
4088             connection->num_packets_completed = 0;
4089         }
4090     }
4091 
4092     packet[2] = size - 3;
4093     packet[3] = num_handles;
4094 
4095     hci_stack->host_completed_packets = 0;
4096 
4097     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4098     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4099 
4100     // release packet buffer for synchronous transport implementations
4101     if (hci_transport_synchronous()){
4102         hci_release_packet_buffer();
4103         hci_emit_transport_packet_sent();
4104     }
4105 }
4106 #endif
4107 
4108 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4109     UNUSED(ds);
4110     hci_stack->substate = HCI_HALTING_CLOSE;
4111     // allow packet handlers to defer final shutdown
4112     hci_emit_state();
4113     hci_run();
4114 }
4115 
4116 static bool hci_run_acl_fragments(void){
4117     if (hci_stack->acl_fragmentation_total_size > 0u) {
4118         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4119         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4120         if (connection) {
4121             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4122                 hci_send_acl_packet_fragments(connection);
4123                 return true;
4124             }
4125         } else {
4126             // connection gone -> discard further fragments
4127             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4128             hci_stack->acl_fragmentation_total_size = 0;
4129             hci_stack->acl_fragmentation_pos = 0;
4130         }
4131     }
4132     return false;
4133 }
4134 
4135 #ifdef ENABLE_CLASSIC
4136 static bool hci_run_general_gap_classic(void){
4137 
4138     // assert stack is working and classic is active
4139     if (hci_classic_supported() == false)      return false;
4140     if (hci_stack->state != HCI_STATE_WORKING) return false;
4141 
4142     // decline incoming connections
4143     if (hci_stack->decline_reason){
4144         uint8_t reason = hci_stack->decline_reason;
4145         hci_stack->decline_reason = 0;
4146         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4147         return true;
4148     }
4149 
4150     if (hci_stack->gap_tasks != 0){
4151         hci_run_gap_tasks_classic();
4152         return true;
4153     }
4154 
4155     // start/stop inquiry
4156     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4157         uint8_t duration = hci_stack->inquiry_state;
4158         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4159         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4160         return true;
4161     }
4162     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4163         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4164         hci_send_cmd(&hci_inquiry_cancel);
4165         return true;
4166     }
4167     // remote name request
4168     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4169         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4170         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4171                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4172         return true;
4173     }
4174 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4175     // Local OOB data
4176     if (hci_stack->classic_read_local_oob_data){
4177         hci_stack->classic_read_local_oob_data = false;
4178         if (hci_stack->local_supported_commands[1] & 0x10u){
4179             hci_send_cmd(&hci_read_local_extended_oob_data);
4180         } else {
4181             hci_send_cmd(&hci_read_local_oob_data);
4182         }
4183     }
4184 #endif
4185     // pairing
4186     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4187         uint8_t state = hci_stack->gap_pairing_state;
4188         uint8_t pin_code[16];
4189         switch (state){
4190             case GAP_PAIRING_STATE_SEND_PIN:
4191                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4192                 memset(pin_code, 0, 16);
4193                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4194                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4195                 break;
4196             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4197                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4198                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4199                 break;
4200             case GAP_PAIRING_STATE_SEND_PASSKEY:
4201                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4202                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4203                 break;
4204             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4205                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4206                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4207                 break;
4208             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4209                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4210                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4211                 break;
4212             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4213                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4214                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4215                 break;
4216             default:
4217                 break;
4218         }
4219         return true;
4220     }
4221     return false;
4222 }
4223 #endif
4224 
4225 #ifdef ENABLE_BLE
4226 static bool hci_run_general_gap_le(void){
4227 
4228     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4229 
4230     if (hci_stack->state != HCI_STATE_WORKING) return false;
4231     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4232 
4233 
4234     // Phase 1: collect what to stop
4235 
4236     bool scanning_stop = false;
4237     bool connecting_stop = false;
4238     bool advertising_stop = false;
4239 
4240 #ifndef ENABLE_LE_CENTRAL
4241     UNUSED(scanning_stop);
4242     UNUSED(connecting_stop);
4243 #endif
4244 #ifndef ENABLE_LE_PERIPHERAL
4245     UNUSED(advertising_stop);
4246 #endif
4247 
4248     // check if own address changes
4249     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4250 
4251     // check if whitelist needs modification
4252     bool whitelist_modification_pending = false;
4253     btstack_linked_list_iterator_t lit;
4254     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4255     while (btstack_linked_list_iterator_has_next(&lit)){
4256         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4257         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4258             whitelist_modification_pending = true;
4259             break;
4260         }
4261     }
4262     // check if resolving list needs modification
4263     bool resolving_list_modification_pending = false;
4264 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4265     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4266 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4267         resolving_list_modification_pending = true;
4268     }
4269 #endif
4270 
4271 #ifdef ENABLE_LE_CENTRAL
4272     // scanning control
4273     if (hci_stack->le_scanning_active) {
4274         // stop if:
4275         // - parameter change required
4276         // - it's disabled
4277         // - whitelist change required but used for scanning
4278         // - resolving list modified
4279         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4280         if ((hci_stack->le_scanning_param_update) ||
4281             !hci_stack->le_scanning_enabled ||
4282             scanning_uses_whitelist ||
4283             resolving_list_modification_pending){
4284 
4285             scanning_stop = true;
4286         }
4287     }
4288 #endif
4289 
4290 #ifdef ENABLE_LE_CENTRAL
4291     // connecting control
4292     bool connecting_with_whitelist;
4293     switch (hci_stack->le_connecting_state){
4294         case LE_CONNECTING_DIRECT:
4295         case LE_CONNECTING_WHITELIST:
4296             // stop connecting if:
4297             // - connecting uses white and whitelist modification pending
4298             // - if it got disabled
4299             // - resolving list modified
4300             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4301             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4302                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4303                 resolving_list_modification_pending) {
4304 
4305                 connecting_stop = true;
4306             }
4307             break;
4308         default:
4309             break;
4310     }
4311 #endif
4312 
4313 #ifdef ENABLE_LE_PERIPHERAL
4314     // le advertisement control
4315     if (hci_stack->le_advertisements_active){
4316         // stop if:
4317         // - parameter change required
4318         // - random address used in advertising and changes
4319         // - it's disabled
4320         // - whitelist change required but used for advertisement filter policy
4321         // - resolving list modified
4322         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4323         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4324         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4325         if (advertising_change ||
4326             (advertising_uses_random_address && random_address_change) ||
4327             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4328             (advertising_uses_whitelist && whitelist_modification_pending) ||
4329             resolving_list_modification_pending) {
4330 
4331             advertising_stop = true;
4332         }
4333     }
4334 #endif
4335 
4336 
4337     // Phase 2: stop everything that should be off during modifications
4338 
4339 #ifdef ENABLE_LE_CENTRAL
4340     if (scanning_stop){
4341         hci_stack->le_scanning_active = false;
4342         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4343         return true;
4344     }
4345 #endif
4346 
4347 #ifdef ENABLE_LE_CENTRAL
4348     if (connecting_stop){
4349         hci_send_cmd(&hci_le_create_connection_cancel);
4350         return true;
4351     }
4352 #endif
4353 
4354 #ifdef ENABLE_LE_PERIPHERAL
4355     if (advertising_stop){
4356         hci_stack->le_advertisements_active = false;
4357         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4358         return true;
4359     }
4360 #endif
4361 
4362     // Phase 3: modify
4363 
4364     if (random_address_change){
4365         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4366         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4367         return true;
4368     }
4369 
4370 #ifdef ENABLE_LE_CENTRAL
4371     if (hci_stack->le_scanning_param_update){
4372         hci_stack->le_scanning_param_update = false;
4373         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4374                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4375         return true;
4376     }
4377 #endif
4378 
4379 #ifdef ENABLE_LE_PERIPHERAL
4380     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4381         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4382         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4383         hci_send_cmd(&hci_le_set_advertising_parameters,
4384                      hci_stack->le_advertisements_interval_min,
4385                      hci_stack->le_advertisements_interval_max,
4386                      hci_stack->le_advertisements_type,
4387                      hci_stack->le_advertisements_own_addr_type,
4388                      hci_stack->le_advertisements_direct_address_type,
4389                      hci_stack->le_advertisements_direct_address,
4390                      hci_stack->le_advertisements_channel_map,
4391                      hci_stack->le_advertisements_filter_policy);
4392         return true;
4393     }
4394     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4395         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4396         uint8_t adv_data_clean[31];
4397         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4398         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4399                      hci_stack->le_advertisements_data_len);
4400         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4401         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4402         return true;
4403     }
4404     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4405         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4406         uint8_t scan_data_clean[31];
4407         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4408         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4409                      hci_stack->le_scan_response_data_len);
4410         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4411         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4412         return true;
4413     }
4414 #endif
4415 
4416 
4417 #ifdef ENABLE_LE_CENTRAL
4418     // if connect with whitelist was active and is not cancelled yet, wait until next time
4419     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4420 #endif
4421 
4422     // LE Whitelist Management
4423     if (whitelist_modification_pending){
4424         // add/remove entries
4425         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4426         while (btstack_linked_list_iterator_has_next(&lit)){
4427             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4428 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4429 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4430 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4431 				return true;
4432 			}
4433             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4434 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4435                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4436                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4437                 return true;
4438             }
4439             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4440 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4441 				btstack_memory_whitelist_entry_free(entry);
4442             }
4443         }
4444     }
4445 
4446 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4447     // LE Resolving List Management
4448     if (resolving_list_supported) {
4449 		uint16_t i;
4450 		switch (hci_stack->le_resolving_list_state) {
4451 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4452 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4453 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4454 				return true;
4455 			case LE_RESOLVING_LIST_READ_SIZE:
4456 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4457 				hci_send_cmd(&hci_le_read_resolving_list_size);
4458 				return true;
4459 			case LE_RESOLVING_LIST_SEND_CLEAR:
4460 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4461 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4462 							  sizeof(hci_stack->le_resolving_list_add_entries));
4463 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4464 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4465 				hci_send_cmd(&hci_le_clear_resolving_list);
4466 				return true;
4467 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4468 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4469 					uint8_t offset = i >> 3;
4470 					uint8_t mask = 1 << (i & 7);
4471 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4472 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4473 					bd_addr_t peer_identity_addreses;
4474 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4475 					sm_key_t peer_irk;
4476 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4477 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4478 
4479 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4480 					// trigger whitelist entry 'update' (work around for controller bug)
4481 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4482 					while (btstack_linked_list_iterator_has_next(&lit)) {
4483 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4484 						if (entry->address_type != peer_identity_addr_type) continue;
4485 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4486 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4487 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4488 					}
4489 #endif
4490 
4491 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4492 								 peer_identity_addreses);
4493 					return true;
4494 				}
4495 
4496 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4497 
4498 				/* fall through */
4499 
4500 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4501 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4502 					uint8_t offset = i >> 3;
4503 					uint8_t mask = 1 << (i & 7);
4504 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4505 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4506 					bd_addr_t peer_identity_addreses;
4507 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4508 					sm_key_t peer_irk;
4509 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4510 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4511 					const uint8_t *local_irk = gap_get_persistent_irk();
4512 					// command uses format specifier 'P' that stores 16-byte value without flip
4513 					uint8_t local_irk_flipped[16];
4514 					uint8_t peer_irk_flipped[16];
4515 					reverse_128(local_irk, local_irk_flipped);
4516 					reverse_128(peer_irk, peer_irk_flipped);
4517 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4518 								 peer_irk_flipped, local_irk_flipped);
4519 					return true;
4520 				}
4521 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4522 				break;
4523 
4524 			default:
4525 				break;
4526 		}
4527 	}
4528     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4529 #endif
4530 
4531     // Phase 4: restore state
4532 
4533 #ifdef ENABLE_LE_CENTRAL
4534     // re-start scanning
4535     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4536         hci_stack->le_scanning_active = true;
4537         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4538         return true;
4539     }
4540 #endif
4541 
4542 #ifdef ENABLE_LE_CENTRAL
4543     // re-start connecting
4544     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4545         bd_addr_t null_addr;
4546         memset(null_addr, 0, 6);
4547         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4548         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4549         hci_send_cmd(&hci_le_create_connection,
4550                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4551                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4552                      1,         // use whitelist
4553                      0,         // peer address type
4554                      null_addr, // peer bd addr
4555                      hci_stack->le_connection_own_addr_type,   // our addr type:
4556                      hci_stack->le_connection_interval_min,    // conn interval min
4557                      hci_stack->le_connection_interval_max,    // conn interval max
4558                      hci_stack->le_connection_latency,         // conn latency
4559                      hci_stack->le_supervision_timeout,        // conn latency
4560                      hci_stack->le_minimum_ce_length,          // min ce length
4561                      hci_stack->le_maximum_ce_length           // max ce length
4562         );
4563         return true;
4564     }
4565 #endif
4566 
4567 #ifdef ENABLE_LE_PERIPHERAL
4568     // re-start advertising
4569     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4570         // check if advertisements should be enabled given
4571         hci_stack->le_advertisements_active = true;
4572         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4573         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4574         return true;
4575     }
4576 #endif
4577 
4578     return false;
4579 }
4580 #endif
4581 
4582 static bool hci_run_general_pending_commands(void){
4583     btstack_linked_item_t * it;
4584     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4585         hci_connection_t * connection = (hci_connection_t *) it;
4586 
4587         switch(connection->state){
4588             case SEND_CREATE_CONNECTION:
4589                 switch(connection->address_type){
4590 #ifdef ENABLE_CLASSIC
4591                     case BD_ADDR_TYPE_ACL:
4592                         log_info("sending hci_create_connection");
4593                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4594                         break;
4595 #endif
4596                     default:
4597 #ifdef ENABLE_BLE
4598 #ifdef ENABLE_LE_CENTRAL
4599                         log_info("sending hci_le_create_connection");
4600                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4601                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4602                         hci_send_cmd(&hci_le_create_connection,
4603                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4604                                      hci_stack->le_connection_scan_window,      // conn scan windows
4605                                      0,         // don't use whitelist
4606                                      connection->address_type, // peer address type
4607                                      connection->address,      // peer bd addr
4608                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4609                                      hci_stack->le_connection_interval_min,    // conn interval min
4610                                      hci_stack->le_connection_interval_max,    // conn interval max
4611                                      hci_stack->le_connection_latency,         // conn latency
4612                                      hci_stack->le_supervision_timeout,        // conn latency
4613                                      hci_stack->le_minimum_ce_length,          // min ce length
4614                                      hci_stack->le_maximum_ce_length          // max ce length
4615                         );
4616                         connection->state = SENT_CREATE_CONNECTION;
4617 #endif
4618 #endif
4619                         break;
4620                 }
4621                 return true;
4622 
4623 #ifdef ENABLE_CLASSIC
4624             case RECEIVED_CONNECTION_REQUEST:
4625                 connection->role  = HCI_ROLE_SLAVE;
4626                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4627                     log_info("sending hci_accept_connection_request");
4628                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4629                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4630                 }
4631                 return true;
4632 #endif
4633 
4634 #ifdef ENABLE_BLE
4635 #ifdef ENABLE_LE_CENTRAL
4636             case SEND_CANCEL_CONNECTION:
4637                 connection->state = SENT_CANCEL_CONNECTION;
4638                 hci_send_cmd(&hci_le_create_connection_cancel);
4639                 return true;
4640 #endif
4641 #endif
4642             case SEND_DISCONNECT:
4643                 connection->state = SENT_DISCONNECT;
4644                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4645                 return true;
4646 
4647             default:
4648                 break;
4649         }
4650 
4651         // no further commands if connection is about to get shut down
4652         if (connection->state == SENT_DISCONNECT) continue;
4653 
4654         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4655             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4656             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4657             return true;
4658         }
4659 
4660 #ifdef ENABLE_CLASSIC
4661 
4662         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4663             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4664             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4665             return true;
4666         }
4667 
4668         // Handling link key request requires remote supported features
4669         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4670             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4671             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4672 
4673             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4674             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4675             if (have_link_key && security_level_sufficient){
4676                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4677             } else {
4678                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4679             }
4680             return true;
4681         }
4682 
4683         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4684             log_info("denying to pin request");
4685             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4686             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4687             return true;
4688         }
4689 
4690         // security assessment requires remote features
4691         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4692             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4693             hci_ssp_assess_security_on_io_cap_request(connection);
4694             // 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
4695         }
4696 
4697         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4698             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4699             // set authentication requirements:
4700             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4701             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4702             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4703             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4704                 authreq |= 1;
4705             }
4706             bool bonding = hci_stack->bondable;
4707             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4708                 // if we have received IO Cap Response, we're in responder role
4709                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4710                 if (bonding && !remote_bonding){
4711                     log_info("Remote not bonding, dropping local flag");
4712                     bonding = false;
4713                 }
4714             }
4715             if (bonding){
4716                 if (connection->bonding_flags & BONDING_DEDICATED){
4717                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4718                 } else {
4719                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4720                 }
4721             }
4722             uint8_t have_oob_data = 0;
4723 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4724             if (connection->classic_oob_c_192 != NULL){
4725                     have_oob_data |= 1;
4726             }
4727             if (connection->classic_oob_c_256 != NULL){
4728                 have_oob_data |= 2;
4729             }
4730 #endif
4731             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4732             return true;
4733         }
4734 
4735         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4736             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4737             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4738             return true;
4739         }
4740 
4741 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4742         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4743             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4744             const uint8_t zero[16] = { 0 };
4745             const uint8_t * r_192 = zero;
4746             const uint8_t * c_192 = zero;
4747             const uint8_t * r_256 = zero;
4748             const uint8_t * c_256 = zero;
4749             // verify P-256 OOB
4750             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4751                 c_256 = connection->classic_oob_c_256;
4752                 if (connection->classic_oob_r_256 != NULL) {
4753                     r_256 = connection->classic_oob_r_256;
4754                 }
4755             }
4756             // verify P-192 OOB
4757             if ((connection->classic_oob_c_192 != NULL)) {
4758                 c_192 = connection->classic_oob_c_192;
4759                 if (connection->classic_oob_r_192 != NULL) {
4760                     r_192 = connection->classic_oob_r_192;
4761                 }
4762             }
4763 
4764             // assess security
4765             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4766             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4767             if (need_level_4 && !can_reach_level_4){
4768                 log_info("Level 4 required, but not possible -> abort");
4769                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4770                 // send oob negative reply
4771                 c_256 = NULL;
4772                 c_192 = NULL;
4773             }
4774 
4775             // Reply
4776             if (c_256 != zero) {
4777                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4778             } else if (c_192 != zero){
4779                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4780             } else {
4781                 hci_stack->classic_oob_con_handle = connection->con_handle;
4782                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4783             }
4784             return true;
4785         }
4786 #endif
4787 
4788         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4789             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4790             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4791             return true;
4792         }
4793 
4794         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4795             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4796             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4797             return true;
4798         }
4799 
4800         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4801             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4802             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4803             return true;
4804         }
4805 
4806         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4807             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4808             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4809             connection->state = SENT_DISCONNECT;
4810             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4811             return true;
4812         }
4813 
4814         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4815             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4816             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4817             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4818             return true;
4819         }
4820 
4821         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4822             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4823             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4824             return true;
4825         }
4826 
4827         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4828             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4829             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4830             return true;
4831         }
4832 
4833         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4834             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4835             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4836             return true;
4837         }
4838 
4839         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4840             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4841             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4842             return true;
4843         }
4844 
4845         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4846             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4847             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4848             return true;
4849         }
4850 #endif
4851 
4852         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4853             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4854 #ifdef ENABLE_CLASSIC
4855             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4856 #endif
4857             if (connection->state != SENT_DISCONNECT){
4858                 connection->state = SENT_DISCONNECT;
4859                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4860                 return true;
4861             }
4862         }
4863 
4864 #ifdef ENABLE_CLASSIC
4865         uint16_t sniff_min_interval;
4866         switch (connection->sniff_min_interval){
4867             case 0:
4868                 break;
4869             case 0xffff:
4870                 connection->sniff_min_interval = 0;
4871                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4872                 return true;
4873             default:
4874                 sniff_min_interval = connection->sniff_min_interval;
4875                 connection->sniff_min_interval = 0;
4876                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4877                 return true;
4878         }
4879 
4880         if (connection->sniff_subrating_max_latency != 0xffff){
4881             uint16_t max_latency = connection->sniff_subrating_max_latency;
4882             connection->sniff_subrating_max_latency = 0;
4883             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4884             return true;
4885         }
4886 
4887         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4888             uint8_t service_type = (uint8_t) connection->qos_service_type;
4889             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4890             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);
4891             return true;
4892         }
4893 
4894         if (connection->request_role != HCI_ROLE_INVALID){
4895             hci_role_t role = connection->request_role;
4896             connection->request_role = HCI_ROLE_INVALID;
4897             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4898             return true;
4899         }
4900 #endif
4901 
4902 #ifdef ENABLE_BLE
4903         switch (connection->le_con_parameter_update_state){
4904             // response to L2CAP CON PARAMETER UPDATE REQUEST
4905             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4906                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4907                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4908                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4909                              0x0000, 0xffff);
4910                 return true;
4911             case CON_PARAMETER_UPDATE_REPLY:
4912                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4913                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4914                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4915                              0x0000, 0xffff);
4916                 return true;
4917             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4918                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4919                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4920                 return true;
4921             default:
4922                 break;
4923         }
4924         if (connection->le_phy_update_all_phys != 0xffu){
4925             uint8_t all_phys = connection->le_phy_update_all_phys;
4926             connection->le_phy_update_all_phys = 0xff;
4927             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);
4928             return true;
4929         }
4930 #endif
4931     }
4932     return false;
4933 }
4934 
4935 static void hci_run(void){
4936 
4937     bool done;
4938 
4939     // send continuation fragments first, as they block the prepared packet buffer
4940     done = hci_run_acl_fragments();
4941     if (done) return;
4942 
4943 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4944     // send host num completed packets next as they don't require num_cmd_packets > 0
4945     if (!hci_can_send_comand_packet_transport()) return;
4946     if (hci_stack->host_completed_packets){
4947         hci_host_num_completed_packets();
4948         return;
4949     }
4950 #endif
4951 
4952     if (!hci_can_send_command_packet_now()) return;
4953 
4954     // global/non-connection oriented commands
4955 
4956 
4957 #ifdef ENABLE_CLASSIC
4958     // general gap classic
4959     done = hci_run_general_gap_classic();
4960     if (done) return;
4961 #endif
4962 
4963 #ifdef ENABLE_BLE
4964     // general gap le
4965     done = hci_run_general_gap_le();
4966     if (done) return;
4967 #endif
4968 
4969     // send pending HCI commands
4970     done = hci_run_general_pending_commands();
4971     if (done) return;
4972 
4973     // stack state sub statemachines
4974     hci_connection_t * connection;
4975     switch (hci_stack->state){
4976         case HCI_STATE_INITIALIZING:
4977             hci_initializing_run();
4978             break;
4979 
4980         case HCI_STATE_HALTING:
4981 
4982             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4983             switch (hci_stack->substate){
4984                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4985                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4986 
4987 #ifdef ENABLE_BLE
4988 #ifdef ENABLE_LE_CENTRAL
4989                     // free whitelist entries
4990                     {
4991                         btstack_linked_list_iterator_t lit;
4992                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4993                         while (btstack_linked_list_iterator_has_next(&lit)){
4994                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4995                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4996                             btstack_memory_whitelist_entry_free(entry);
4997                         }
4998                     }
4999 #endif
5000 #endif
5001                     // close all open connections
5002                     connection =  (hci_connection_t *) hci_stack->connections;
5003                     if (connection){
5004                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5005                         if (!hci_can_send_command_packet_now()) return;
5006 
5007                         // check state
5008                         if (connection->state == SENT_DISCONNECT) return;
5009                         connection->state = SENT_DISCONNECT;
5010 
5011                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5012 
5013                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5014                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5015 
5016                         // ... which would be ignored anyway as we shutdown (free) the connection now
5017                         hci_shutdown_connection(connection);
5018 
5019                         // finally, send the disconnect command
5020                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5021                         return;
5022                     }
5023 
5024                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5025                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5026                         log_info("HCI_STATE_HALTING: wait 50 ms");
5027                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5028                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5029                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5030                         btstack_run_loop_add_timer(&hci_stack->timeout);
5031                         break;
5032                     }
5033 
5034                     /* fall through */
5035 
5036                 case HCI_HALTING_CLOSE:
5037                     log_info("HCI_STATE_HALTING, calling off");
5038 
5039                     // switch mode
5040                     hci_power_control_off();
5041 
5042                     log_info("HCI_STATE_HALTING, emitting state");
5043                     hci_emit_state();
5044                     log_info("HCI_STATE_HALTING, done");
5045                     break;
5046 
5047                 case HCI_HALTING_W4_TIMER:
5048                     // keep waiting
5049 
5050                     break;
5051                 default:
5052                     break;
5053             }
5054 
5055             break;
5056 
5057         case HCI_STATE_FALLING_ASLEEP:
5058             switch(hci_stack->substate) {
5059                 case HCI_FALLING_ASLEEP_DISCONNECT:
5060                     log_info("HCI_STATE_FALLING_ASLEEP");
5061                     // close all open connections
5062                     connection =  (hci_connection_t *) hci_stack->connections;
5063                     if (connection){
5064 
5065                         // send disconnect
5066                         if (!hci_can_send_command_packet_now()) return;
5067 
5068                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5069                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5070 
5071                         // send disconnected event right away - causes higher layer connections to get closed, too.
5072                         hci_shutdown_connection(connection);
5073                         return;
5074                     }
5075 
5076                     if (hci_classic_supported()){
5077                         // disable page and inquiry scan
5078                         if (!hci_can_send_command_packet_now()) return;
5079 
5080                         log_info("HCI_STATE_HALTING, disabling inq scans");
5081                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5082 
5083                         // continue in next sub state
5084                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5085                         break;
5086                     }
5087 
5088                     /* fall through */
5089 
5090                 case HCI_FALLING_ASLEEP_COMPLETE:
5091                     log_info("HCI_STATE_HALTING, calling sleep");
5092                     // switch mode
5093                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5094                     hci_emit_state();
5095                     break;
5096 
5097                 default:
5098                     break;
5099             }
5100             break;
5101 
5102         default:
5103             break;
5104     }
5105 }
5106 
5107 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5108     // house-keeping
5109 
5110 #ifdef ENABLE_CLASSIC
5111     bd_addr_t addr;
5112     hci_connection_t * conn;
5113 #endif
5114 #ifdef ENABLE_LE_CENTRAL
5115     uint8_t initiator_filter_policy;
5116 #endif
5117 
5118     uint16_t opcode = little_endian_read_16(packet, 0);
5119     switch (opcode) {
5120         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5121             hci_stack->loopback_mode = packet[3];
5122             break;
5123 
5124 #ifdef ENABLE_CLASSIC
5125         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5126             reverse_bd_addr(&packet[3], addr);
5127             log_info("Create_connection to %s", bd_addr_to_str(addr));
5128 
5129             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5130             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5131                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5132                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5133             }
5134 
5135             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5136             if (!conn) {
5137                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5138                 if (!conn) {
5139                     // notify client that alloc failed
5140                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5141                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5142                 }
5143                 conn->state = SEND_CREATE_CONNECTION;
5144                 conn->role  = HCI_ROLE_MASTER;
5145             }
5146 
5147             conn->con_handle = HCI_CON_HANDLE_INVALID;
5148             conn->role = HCI_ROLE_INVALID;
5149 
5150             log_info("conn state %u", conn->state);
5151             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5152             switch (conn->state) {
5153                 // if connection active exists
5154                 case OPEN:
5155                     // and OPEN, emit connection complete command
5156                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5157                     // packet not sent to controller
5158                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5159                 case RECEIVED_DISCONNECTION_COMPLETE:
5160                     // create connection triggered in disconnect complete event, let's do it now
5161                     break;
5162                 case SEND_CREATE_CONNECTION:
5163                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5164                     break;
5165                 default:
5166                     // otherwise, just ignore as it is already in the open process
5167                     // packet not sent to controller
5168                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5169             }
5170             conn->state = SENT_CREATE_CONNECTION;
5171 
5172             // track outgoing connection
5173             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5174             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5175             break;
5176 
5177 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5178         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5179             // setup_synchronous_connection? Voice setting at offset 22
5180             // TODO: compare to current setting if sco connection already active
5181             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5182             break;
5183         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5184             // accept_synchronous_connection? Voice setting at offset 18
5185             // TODO: compare to current setting if sco connection already active
5186             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5187             break;
5188 #endif
5189 #endif
5190 
5191 #ifdef ENABLE_BLE
5192 #ifdef ENABLE_LE_CENTRAL
5193         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5194             // white list used?
5195             initiator_filter_policy = packet[7];
5196             switch (initiator_filter_policy) {
5197                 case 0:
5198                     // whitelist not used
5199                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5200                     break;
5201                 case 1:
5202                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5203                     break;
5204                 default:
5205                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5206                     break;
5207             }
5208             // track outgoing connection
5209             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5210             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5211             break;
5212         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5213             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5214             break;
5215 #endif
5216 #endif
5217         default:
5218             break;
5219     }
5220 
5221     hci_stack->num_cmd_packets--;
5222 
5223     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5224     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5225     if (err != 0){
5226         return ERROR_CODE_HARDWARE_FAILURE;
5227     }
5228     return ERROR_CODE_SUCCESS;
5229 }
5230 
5231 // disconnect because of security block
5232 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5233     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5234     if (!connection) return;
5235     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5236 }
5237 
5238 
5239 // Configure Secure Simple Pairing
5240 
5241 #ifdef ENABLE_CLASSIC
5242 
5243 // enable will enable SSP during init
5244 void gap_ssp_set_enable(int enable){
5245     hci_stack->ssp_enable = enable;
5246 }
5247 
5248 static int hci_local_ssp_activated(void){
5249     return gap_ssp_supported() && hci_stack->ssp_enable;
5250 }
5251 
5252 // if set, BTstack will respond to io capability request using authentication requirement
5253 void gap_ssp_set_io_capability(int io_capability){
5254     hci_stack->ssp_io_capability = io_capability;
5255 }
5256 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5257     hci_stack->ssp_authentication_requirement = authentication_requirement;
5258 }
5259 
5260 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5261 void gap_ssp_set_auto_accept(int auto_accept){
5262     hci_stack->ssp_auto_accept = auto_accept;
5263 }
5264 
5265 void gap_secure_connections_enable(bool enable){
5266     hci_stack->secure_connections_enable = enable;
5267 }
5268 
5269 #endif
5270 
5271 // va_list part of hci_send_cmd
5272 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5273     if (!hci_can_send_command_packet_now()){
5274         log_error("hci_send_cmd called but cannot send packet now");
5275         return ERROR_CODE_COMMAND_DISALLOWED;
5276     }
5277 
5278     // for HCI INITIALIZATION
5279     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5280     hci_stack->last_cmd_opcode = cmd->opcode;
5281 
5282     hci_reserve_packet_buffer();
5283     uint8_t * packet = hci_stack->hci_packet_buffer;
5284     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5285     uint8_t status = hci_send_cmd_packet(packet, size);
5286 
5287     // release packet buffer on error or for synchronous transport implementations
5288     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5289         hci_release_packet_buffer();
5290         hci_emit_transport_packet_sent();
5291     }
5292 
5293     return status;
5294 }
5295 
5296 /**
5297  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5298  */
5299 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5300     va_list argptr;
5301     va_start(argptr, cmd);
5302     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5303     va_end(argptr);
5304     return status;
5305 }
5306 
5307 // Create various non-HCI events.
5308 // TODO: generalize, use table similar to hci_create_command
5309 
5310 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5311     // dump packet
5312     if (dump) {
5313         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5314     }
5315 
5316     // dispatch to all event handlers
5317     btstack_linked_list_iterator_t it;
5318     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5319     while (btstack_linked_list_iterator_has_next(&it)){
5320         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5321         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5322     }
5323 }
5324 
5325 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5326     if (!hci_stack->acl_packet_handler) return;
5327     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5328 }
5329 
5330 #ifdef ENABLE_CLASSIC
5331 static void hci_notify_if_sco_can_send_now(void){
5332     // notify SCO sender if waiting
5333     if (!hci_stack->sco_waiting_for_can_send_now) return;
5334     if (hci_can_send_sco_packet_now()){
5335         hci_stack->sco_waiting_for_can_send_now = 0;
5336         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5337         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5338         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5339     }
5340 }
5341 
5342 // parsing end emitting has been merged to reduce code size
5343 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5344     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5345 
5346     uint8_t * eir_data;
5347     ad_context_t context;
5348     const uint8_t * name;
5349     uint8_t         name_len;
5350 
5351     if (size < 3) return;
5352 
5353     int event_type = hci_event_packet_get_type(packet);
5354     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5355     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5356 
5357     switch (event_type){
5358         case HCI_EVENT_INQUIRY_RESULT:
5359         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5360             if (size != (3 + (num_responses * 14))) return;
5361             break;
5362         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5363             if (size != 257) return;
5364             if (num_responses != 1) return;
5365             break;
5366         default:
5367             return;
5368     }
5369 
5370     // event[1] is set at the end
5371     int i;
5372     for (i=0; i<num_responses;i++){
5373         memset(event, 0, sizeof(event));
5374         event[0] = GAP_EVENT_INQUIRY_RESULT;
5375         uint8_t event_size = 27;    // if name is not set by EIR
5376 
5377         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5378         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5379         (void)memcpy(&event[9],
5380                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5381                      3); // class of device
5382         (void)memcpy(&event[12],
5383                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5384                      2); // clock offset
5385 
5386         switch (event_type){
5387             case HCI_EVENT_INQUIRY_RESULT:
5388                 // 14,15,16,17 = 0, size 18
5389                 break;
5390             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5391                 event[14] = 1;
5392                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5393                 // 16,17 = 0, size 18
5394                 break;
5395             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5396                 event[14] = 1;
5397                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5398                 // EIR packets only contain a single inquiry response
5399                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5400                 name = NULL;
5401                 // Iterate over EIR data
5402                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5403                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5404                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5405                     const uint8_t * data = ad_iterator_get_data(&context);
5406                     // Prefer Complete Local Name over Shortened Local Name
5407                     switch (data_type){
5408                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5409                             if (name) continue;
5410                             /* fall through */
5411                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5412                             name = data;
5413                             name_len = data_size;
5414                             break;
5415                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5416                             if (data_size != 8) break;
5417                             event[16] = 1;
5418                             memcpy(&event[17], data, 8);
5419                             break;
5420                         default:
5421                             break;
5422                     }
5423                 }
5424                 if (name){
5425                     event[25] = 1;
5426                     // truncate name if needed
5427                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5428                     event[26] = len;
5429                     (void)memcpy(&event[27], name, len);
5430                     event_size += len;
5431                 }
5432                 break;
5433             default:
5434                 return;
5435         }
5436         event[1] = event_size - 2;
5437         hci_emit_event(event, event_size, 1);
5438     }
5439 }
5440 #endif
5441 
5442 void hci_emit_state(void){
5443     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5444     uint8_t event[3];
5445     event[0] = BTSTACK_EVENT_STATE;
5446     event[1] = sizeof(event) - 2u;
5447     event[2] = hci_stack->state;
5448     hci_emit_event(event, sizeof(event), 1);
5449 }
5450 
5451 #ifdef ENABLE_CLASSIC
5452 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5453     uint8_t event[13];
5454     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5455     event[1] = sizeof(event) - 2;
5456     event[2] = status;
5457     little_endian_store_16(event, 3, con_handle);
5458     reverse_bd_addr(address, &event[5]);
5459     event[11] = 1; // ACL connection
5460     event[12] = 0; // encryption disabled
5461     hci_emit_event(event, sizeof(event), 1);
5462 }
5463 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5464     if (disable_l2cap_timeouts) return;
5465     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5466     uint8_t event[4];
5467     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5468     event[1] = sizeof(event) - 2;
5469     little_endian_store_16(event, 2, conn->con_handle);
5470     hci_emit_event(event, sizeof(event), 1);
5471 }
5472 #endif
5473 
5474 #ifdef ENABLE_BLE
5475 #ifdef ENABLE_LE_CENTRAL
5476 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){
5477     uint8_t event[21];
5478     event[0] = HCI_EVENT_LE_META;
5479     event[1] = sizeof(event) - 2u;
5480     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5481     event[3] = status;
5482     little_endian_store_16(event, 4, con_handle);
5483     event[6] = 0; // TODO: role
5484     event[7] = address_type;
5485     reverse_bd_addr(address, &event[8]);
5486     little_endian_store_16(event, 14, 0); // interval
5487     little_endian_store_16(event, 16, 0); // latency
5488     little_endian_store_16(event, 18, 0); // supervision timeout
5489     event[20] = 0; // master clock accuracy
5490     hci_emit_event(event, sizeof(event), 1);
5491 }
5492 #endif
5493 #endif
5494 
5495 static void hci_emit_transport_packet_sent(void){
5496     // notify upper stack that it might be possible to send again
5497     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5498     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5499 }
5500 
5501 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5502     uint8_t event[6];
5503     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5504     event[1] = sizeof(event) - 2u;
5505     event[2] = 0; // status = OK
5506     little_endian_store_16(event, 3, con_handle);
5507     event[5] = reason;
5508     hci_emit_event(event, sizeof(event), 1);
5509 }
5510 
5511 static void hci_emit_nr_connections_changed(void){
5512     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5513     uint8_t event[3];
5514     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5515     event[1] = sizeof(event) - 2u;
5516     event[2] = nr_hci_connections();
5517     hci_emit_event(event, sizeof(event), 1);
5518 }
5519 
5520 static void hci_emit_hci_open_failed(void){
5521     log_info("BTSTACK_EVENT_POWERON_FAILED");
5522     uint8_t event[2];
5523     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5524     event[1] = sizeof(event) - 2u;
5525     hci_emit_event(event, sizeof(event), 1);
5526 }
5527 
5528 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5529     log_info("hci_emit_dedicated_bonding_result %u ", status);
5530     uint8_t event[9];
5531     int pos = 0;
5532     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5533     event[pos++] = sizeof(event) - 2u;
5534     event[pos++] = status;
5535     reverse_bd_addr(address, &event[pos]);
5536     hci_emit_event(event, sizeof(event), 1);
5537 }
5538 
5539 
5540 #ifdef ENABLE_CLASSIC
5541 
5542 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5543     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5544     uint8_t event[5];
5545     int pos = 0;
5546     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5547     event[pos++] = sizeof(event) - 2;
5548     little_endian_store_16(event, 2, con_handle);
5549     pos += 2;
5550     event[pos++] = level;
5551     hci_emit_event(event, sizeof(event), 1);
5552 }
5553 
5554 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5555     if (!connection) return LEVEL_0;
5556     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5557     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5558     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5559     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5560     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5561     // LEVEL 4 always requires 128 bit encrytion key size
5562     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5563         security_level = LEVEL_3;
5564     }
5565     return security_level;
5566 }
5567 
5568 static void hci_emit_discoverable_enabled(uint8_t enabled){
5569     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5570     uint8_t event[3];
5571     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5572     event[1] = sizeof(event) - 2;
5573     event[2] = enabled;
5574     hci_emit_event(event, sizeof(event), 1);
5575 }
5576 
5577 // query if remote side supports eSCO
5578 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5579     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5580     if (!connection) return false;
5581     return (connection->remote_supported_features[0] & 1) != 0;
5582 }
5583 
5584 static bool hci_ssp_supported(hci_connection_t * connection){
5585     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5586     return (connection->bonding_flags & mask) == mask;
5587 }
5588 
5589 // query if remote side supports SSP
5590 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5591     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5592     if (!connection) return false;
5593     return hci_ssp_supported(connection) ? 1 : 0;
5594 }
5595 
5596 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5597     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5598 }
5599 
5600 /**
5601  * Check if remote supported features query has completed
5602  */
5603 bool hci_remote_features_available(hci_con_handle_t handle){
5604     hci_connection_t * connection = hci_connection_for_handle(handle);
5605     if (!connection) return false;
5606     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5607 }
5608 
5609 /**
5610  * Trigger remote supported features query
5611  */
5612 void hci_remote_features_query(hci_con_handle_t con_handle){
5613     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5614     if (!connection) return;
5615     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) != 0) return;
5616     connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5617     hci_run();
5618 }
5619 
5620 // GAP API
5621 /**
5622  * @bbrief enable/disable bonding. default is enabled
5623  * @praram enabled
5624  */
5625 void gap_set_bondable_mode(int enable){
5626     hci_stack->bondable = enable ? 1 : 0;
5627 }
5628 /**
5629  * @brief Get bondable mode.
5630  * @return 1 if bondable
5631  */
5632 int gap_get_bondable_mode(void){
5633     return hci_stack->bondable;
5634 }
5635 
5636 /**
5637  * @brief map link keys to security levels
5638  */
5639 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5640     switch (link_key_type){
5641         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5642             return LEVEL_4;
5643         case COMBINATION_KEY:
5644         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5645             return LEVEL_3;
5646         default:
5647             return LEVEL_2;
5648     }
5649 }
5650 
5651 /**
5652  * @brief map link keys to secure connection yes/no
5653  */
5654 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5655     switch (link_key_type){
5656         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5657         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5658             return 1;
5659         default:
5660             return 0;
5661     }
5662 }
5663 
5664 /**
5665  * @brief map link keys to authenticated
5666  */
5667 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5668     switch (link_key_type){
5669         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5670         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5671             return 1;
5672         default:
5673             return 0;
5674     }
5675 }
5676 
5677 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5678     log_info("gap_mitm_protection_required_for_security_level %u", level);
5679     return level > LEVEL_2;
5680 }
5681 
5682 /**
5683  * @brief get current security level
5684  */
5685 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5686     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5687     if (!connection) return LEVEL_0;
5688     return gap_security_level_for_connection(connection);
5689 }
5690 
5691 /**
5692  * @brief request connection to device to
5693  * @result GAP_AUTHENTICATION_RESULT
5694  */
5695 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5696     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5697     if (!connection){
5698         hci_emit_security_level(con_handle, LEVEL_0);
5699         return;
5700     }
5701 
5702     btstack_assert(hci_is_le_connection(connection) == false);
5703 
5704     // 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)
5705     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5706     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5707         requested_level = LEVEL_4;
5708     }
5709 
5710     gap_security_level_t current_level = gap_security_level(con_handle);
5711     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5712         requested_level, connection->requested_security_level, current_level);
5713 
5714     // authentication active if authentication request was sent or planned level > 0
5715     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5716     if (authentication_active){
5717         // authentication already active
5718         if (connection->requested_security_level < requested_level){
5719             // increase requested level as new level is higher
5720             // TODO: handle re-authentication when done
5721             connection->requested_security_level = requested_level;
5722         }
5723     } else {
5724         // no request active, notify if security sufficient
5725         if (requested_level <= current_level){
5726             hci_emit_security_level(con_handle, current_level);
5727             return;
5728         }
5729 
5730         // store request
5731         connection->requested_security_level = requested_level;
5732 
5733         // request remote features if not already active
5734         hci_remote_features_query(con_handle);
5735 
5736         // start to authenticate connection
5737         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5738         hci_run();
5739     }
5740 }
5741 
5742 /**
5743  * @brief start dedicated bonding with device. disconnect after bonding
5744  * @param device
5745  * @param request MITM protection
5746  * @result GAP_DEDICATED_BONDING_COMPLETE
5747  */
5748 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5749 
5750     // create connection state machine
5751     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5752 
5753     if (!connection){
5754         return BTSTACK_MEMORY_ALLOC_FAILED;
5755     }
5756 
5757     // delete linkn key
5758     gap_drop_link_key_for_bd_addr(device);
5759 
5760     // configure LEVEL_2/3, dedicated bonding
5761     connection->state = SEND_CREATE_CONNECTION;
5762     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5763     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5764     connection->bonding_flags = BONDING_DEDICATED;
5765 
5766     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5767 
5768     // handle: connnection failure (connection complete != ok)
5769     // handle: authentication failure
5770     // handle: disconnect on done
5771 
5772     hci_run();
5773 
5774     return 0;
5775 }
5776 
5777 void gap_set_local_name(const char * local_name){
5778     hci_stack->local_name = local_name;
5779     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5780     // also update EIR if not set by user
5781     if (hci_stack->eir_data == NULL){
5782         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5783     }
5784     hci_run();
5785 }
5786 #endif
5787 
5788 
5789 #ifdef ENABLE_BLE
5790 
5791 #ifdef ENABLE_LE_CENTRAL
5792 void gap_start_scan(void){
5793     hci_stack->le_scanning_enabled = true;
5794     hci_run();
5795 }
5796 
5797 void gap_stop_scan(void){
5798     hci_stack->le_scanning_enabled = false;
5799     hci_run();
5800 }
5801 
5802 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5803     hci_stack->le_scan_type          = scan_type;
5804     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5805     hci_stack->le_scan_interval      = scan_interval;
5806     hci_stack->le_scan_window        = scan_window;
5807     hci_stack->le_scanning_param_update = true;
5808     hci_run();
5809 }
5810 
5811 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5812     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5813 }
5814 
5815 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5816     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5817     if (!conn){
5818         // disallow if le connection is already outgoing
5819         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5820             log_error("le connection already active");
5821             return ERROR_CODE_COMMAND_DISALLOWED;
5822         }
5823 
5824         log_info("gap_connect: no connection exists yet, creating context");
5825         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5826         if (!conn){
5827             // notify client that alloc failed
5828             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5829             log_info("gap_connect: failed to alloc hci_connection_t");
5830             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5831         }
5832 
5833         // set le connecting state
5834         if (hci_is_le_connection_type(addr_type)){
5835             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5836         }
5837 
5838         conn->state = SEND_CREATE_CONNECTION;
5839         log_info("gap_connect: send create connection next");
5840         hci_run();
5841         return ERROR_CODE_SUCCESS;
5842     }
5843 
5844     if (!hci_is_le_connection(conn) ||
5845         (conn->state == SEND_CREATE_CONNECTION) ||
5846         (conn->state == SENT_CREATE_CONNECTION)) {
5847         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5848         log_error("gap_connect: classic connection or connect is already being created");
5849         return GATT_CLIENT_IN_WRONG_STATE;
5850     }
5851 
5852     // check if connection was just disconnected
5853     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5854         log_info("gap_connect: send create connection (again)");
5855         conn->state = SEND_CREATE_CONNECTION;
5856         hci_run();
5857         return ERROR_CODE_SUCCESS;
5858     }
5859 
5860     log_info("gap_connect: context exists with state %u", conn->state);
5861     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5862     hci_run();
5863     return ERROR_CODE_SUCCESS;
5864 }
5865 
5866 // @assumption: only a single outgoing LE Connection exists
5867 static hci_connection_t * gap_get_outgoing_connection(void){
5868     btstack_linked_item_t *it;
5869     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5870         hci_connection_t * conn = (hci_connection_t *) it;
5871         if (!hci_is_le_connection(conn)) continue;
5872         switch (conn->state){
5873             case SEND_CREATE_CONNECTION:
5874             case SENT_CREATE_CONNECTION:
5875             case SENT_CANCEL_CONNECTION:
5876                 return conn;
5877             default:
5878                 break;
5879         };
5880     }
5881     return NULL;
5882 }
5883 
5884 uint8_t gap_connect_cancel(void){
5885     hci_connection_t * conn = gap_get_outgoing_connection();
5886     if (!conn) return 0;
5887     switch (conn->state){
5888         case SEND_CREATE_CONNECTION:
5889             // skip sending create connection and emit event instead
5890             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5891             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5892             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5893             btstack_memory_hci_connection_free( conn );
5894             break;
5895         case SENT_CREATE_CONNECTION:
5896             // request to send cancel connection
5897             conn->state = SEND_CANCEL_CONNECTION;
5898             hci_run();
5899             break;
5900         default:
5901             break;
5902     }
5903     return 0;
5904 }
5905 #endif
5906 
5907 #ifdef ENABLE_LE_CENTRAL
5908 /**
5909  * @brief Set connection parameters for outgoing connections
5910  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5911  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5912  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5913  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5914  * @param conn_latency, default: 4
5915  * @param supervision_timeout (unit: 10ms), default: 720 ms
5916  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5917  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5918  */
5919 
5920 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5921     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5922     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5923     hci_stack->le_connection_scan_interval = conn_scan_interval;
5924     hci_stack->le_connection_scan_window = conn_scan_window;
5925     hci_stack->le_connection_interval_min = conn_interval_min;
5926     hci_stack->le_connection_interval_max = conn_interval_max;
5927     hci_stack->le_connection_latency = conn_latency;
5928     hci_stack->le_supervision_timeout = supervision_timeout;
5929     hci_stack->le_minimum_ce_length = min_ce_length;
5930     hci_stack->le_maximum_ce_length = max_ce_length;
5931 }
5932 #endif
5933 
5934 /**
5935  * @brief Updates the connection parameters for a given LE connection
5936  * @param handle
5937  * @param conn_interval_min (unit: 1.25ms)
5938  * @param conn_interval_max (unit: 1.25ms)
5939  * @param conn_latency
5940  * @param supervision_timeout (unit: 10ms)
5941  * @returns 0 if ok
5942  */
5943 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5944     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5945     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5946     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5947     connection->le_conn_interval_min = conn_interval_min;
5948     connection->le_conn_interval_max = conn_interval_max;
5949     connection->le_conn_latency = conn_latency;
5950     connection->le_supervision_timeout = supervision_timeout;
5951     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5952     hci_run();
5953     return 0;
5954 }
5955 
5956 /**
5957  * @brief Request an update of the connection parameter for a given LE connection
5958  * @param handle
5959  * @param conn_interval_min (unit: 1.25ms)
5960  * @param conn_interval_max (unit: 1.25ms)
5961  * @param conn_latency
5962  * @param supervision_timeout (unit: 10ms)
5963  * @returns 0 if ok
5964  */
5965 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5966     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5967     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5968     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5969     connection->le_conn_interval_min = conn_interval_min;
5970     connection->le_conn_interval_max = conn_interval_max;
5971     connection->le_conn_latency = conn_latency;
5972     connection->le_supervision_timeout = supervision_timeout;
5973     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5974     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5975     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5976     return 0;
5977 }
5978 
5979 #ifdef ENABLE_LE_PERIPHERAL
5980 
5981 /**
5982  * @brief Set Advertisement Data
5983  * @param advertising_data_length
5984  * @param advertising_data (max 31 octets)
5985  * @note data is not copied, pointer has to stay valid
5986  */
5987 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5988     hci_stack->le_advertisements_data_len = advertising_data_length;
5989     hci_stack->le_advertisements_data = advertising_data;
5990     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5991     hci_run();
5992 }
5993 
5994 /**
5995  * @brief Set Scan Response Data
5996  * @param advertising_data_length
5997  * @param advertising_data (max 31 octets)
5998  * @note data is not copied, pointer has to stay valid
5999  */
6000 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6001     hci_stack->le_scan_response_data_len = scan_response_data_length;
6002     hci_stack->le_scan_response_data = scan_response_data;
6003     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6004     hci_run();
6005 }
6006 
6007 /**
6008  * @brief Set Advertisement Parameters
6009  * @param adv_int_min
6010  * @param adv_int_max
6011  * @param adv_type
6012  * @param direct_address_type
6013  * @param direct_address
6014  * @param channel_map
6015  * @param filter_policy
6016  *
6017  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6018  */
6019  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6020     uint8_t direct_address_typ, bd_addr_t direct_address,
6021     uint8_t channel_map, uint8_t filter_policy) {
6022 
6023     hci_stack->le_advertisements_interval_min = adv_int_min;
6024     hci_stack->le_advertisements_interval_max = adv_int_max;
6025     hci_stack->le_advertisements_type = adv_type;
6026     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6027     hci_stack->le_advertisements_channel_map = channel_map;
6028     hci_stack->le_advertisements_filter_policy = filter_policy;
6029     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6030                  6);
6031 
6032     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6033     hci_run();
6034  }
6035 
6036 /**
6037  * @brief Enable/Disable Advertisements
6038  * @param enabled
6039  */
6040 void gap_advertisements_enable(int enabled){
6041     hci_stack->le_advertisements_enabled = enabled != 0;
6042     hci_update_advertisements_enabled_for_current_roles();
6043     hci_run();
6044 }
6045 
6046 #endif
6047 
6048 void hci_le_set_own_address_type(uint8_t own_address_type){
6049     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6050     if (own_address_type == hci_stack->le_own_addr_type) return;
6051     hci_stack->le_own_addr_type = own_address_type;
6052 
6053 #ifdef ENABLE_LE_PERIPHERAL
6054     // update advertisement parameters, too
6055     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6056     hci_run();
6057 #endif
6058 #ifdef ENABLE_LE_CENTRAL
6059     // note: we don't update scan parameters or modify ongoing connection attempts
6060 #endif
6061 }
6062 
6063 void hci_le_random_address_set(const bd_addr_t random_address){
6064     memcpy(hci_stack->le_random_address, random_address, 6);
6065     hci_stack->le_random_address_set = true;
6066     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6067     hci_run();
6068 }
6069 
6070 #endif
6071 
6072 uint8_t gap_disconnect(hci_con_handle_t handle){
6073     hci_connection_t * conn = hci_connection_for_handle(handle);
6074     if (!conn){
6075         hci_emit_disconnection_complete(handle, 0);
6076         return 0;
6077     }
6078     // ignore if already disconnected
6079     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6080         return 0;
6081     }
6082     conn->state = SEND_DISCONNECT;
6083     hci_run();
6084     return 0;
6085 }
6086 
6087 int gap_read_rssi(hci_con_handle_t con_handle){
6088     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6089     if (hci_connection == NULL) return 0;
6090     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6091     hci_run();
6092     return 1;
6093 }
6094 
6095 /**
6096  * @brief Get connection type
6097  * @param con_handle
6098  * @result connection_type
6099  */
6100 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6101     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6102     if (!conn) return GAP_CONNECTION_INVALID;
6103     switch (conn->address_type){
6104         case BD_ADDR_TYPE_LE_PUBLIC:
6105         case BD_ADDR_TYPE_LE_RANDOM:
6106             return GAP_CONNECTION_LE;
6107         case BD_ADDR_TYPE_SCO:
6108             return GAP_CONNECTION_SCO;
6109         case BD_ADDR_TYPE_ACL:
6110             return GAP_CONNECTION_ACL;
6111         default:
6112             return GAP_CONNECTION_INVALID;
6113     }
6114 }
6115 
6116 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6117     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6118     if (!conn) return HCI_ROLE_INVALID;
6119     return (hci_role_t) conn->role;
6120 }
6121 
6122 
6123 #ifdef ENABLE_CLASSIC
6124 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6125     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6126     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6127     conn->request_role = role;
6128     hci_run();
6129     return ERROR_CODE_SUCCESS;
6130 }
6131 #endif
6132 
6133 #ifdef ENABLE_BLE
6134 
6135 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){
6136     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6137     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6138 
6139     conn->le_phy_update_all_phys    = all_phys;
6140     conn->le_phy_update_tx_phys     = tx_phys;
6141     conn->le_phy_update_rx_phys     = rx_phys;
6142     conn->le_phy_update_phy_options = phy_options;
6143 
6144     hci_run();
6145 
6146     return 0;
6147 }
6148 
6149 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6150     // check if already in list
6151     btstack_linked_list_iterator_t it;
6152     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6153     while (btstack_linked_list_iterator_has_next(&it)) {
6154         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6155         if (entry->address_type != address_type) {
6156             continue;
6157         }
6158         if (memcmp(entry->address, address, 6) != 0) {
6159             continue;
6160         }
6161 		// disallow if already scheduled to add
6162 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6163 			return ERROR_CODE_COMMAND_DISALLOWED;
6164 		}
6165 		// still on controller, but scheduled to remove -> re-add
6166 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6167 		return ERROR_CODE_SUCCESS;
6168     }
6169     // alloc and add to list
6170     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6171     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6172     entry->address_type = address_type;
6173     (void)memcpy(entry->address, address, 6);
6174     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6175     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6176     return ERROR_CODE_SUCCESS;
6177 }
6178 
6179 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6180     btstack_linked_list_iterator_t it;
6181     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6182     while (btstack_linked_list_iterator_has_next(&it)){
6183         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6184         if (entry->address_type != address_type) {
6185             continue;
6186         }
6187         if (memcmp(entry->address, address, 6) != 0) {
6188             continue;
6189         }
6190         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6191             // remove from controller if already present
6192             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6193         }  else {
6194             // directly remove entry from whitelist
6195             btstack_linked_list_iterator_remove(&it);
6196             btstack_memory_whitelist_entry_free(entry);
6197         }
6198         return ERROR_CODE_SUCCESS;
6199     }
6200     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6201 }
6202 
6203 static void hci_whitelist_clear(void){
6204     btstack_linked_list_iterator_t it;
6205     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6206     while (btstack_linked_list_iterator_has_next(&it)){
6207         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6208         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6209             // remove from controller if already present
6210             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6211             continue;
6212         }
6213         // directly remove entry from whitelist
6214         btstack_linked_list_iterator_remove(&it);
6215         btstack_memory_whitelist_entry_free(entry);
6216     }
6217 }
6218 
6219 /**
6220  * @brief Clear Whitelist
6221  * @returns 0 if ok
6222  */
6223 uint8_t gap_whitelist_clear(void){
6224     hci_whitelist_clear();
6225     hci_run();
6226     return ERROR_CODE_SUCCESS;
6227 }
6228 
6229 /**
6230  * @brief Add Device to Whitelist
6231  * @param address_typ
6232  * @param address
6233  * @returns 0 if ok
6234  */
6235 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6236     uint8_t status = hci_whitelist_add(address_type, address);
6237     if (status){
6238         return status;
6239     }
6240     hci_run();
6241     return ERROR_CODE_SUCCESS;
6242 }
6243 
6244 /**
6245  * @brief Remove Device from Whitelist
6246  * @param address_typ
6247  * @param address
6248  * @returns 0 if ok
6249  */
6250 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6251     uint8_t status = hci_whitelist_remove(address_type, address);
6252     if (status){
6253         return status;
6254     }
6255     hci_run();
6256     return ERROR_CODE_SUCCESS;
6257 }
6258 
6259 #ifdef ENABLE_LE_CENTRAL
6260 /**
6261  *  @brief Connect with Whitelist
6262  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6263  *  @returns - if ok
6264  */
6265 uint8_t gap_connect_with_whitelist(void){
6266     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6267         return ERROR_CODE_COMMAND_DISALLOWED;
6268     }
6269     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6270     hci_run();
6271     return ERROR_CODE_SUCCESS;
6272 }
6273 
6274 /**
6275  * @brief Auto Connection Establishment - Start Connecting to device
6276  * @param address_typ
6277  * @param address
6278  * @returns 0 if ok
6279  */
6280 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6281     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6282         return ERROR_CODE_COMMAND_DISALLOWED;
6283     }
6284 
6285     uint8_t status = hci_whitelist_add(address_type, address);
6286     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6287         return status;
6288     }
6289 
6290     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6291 
6292     hci_run();
6293     return ERROR_CODE_SUCCESS;
6294 }
6295 
6296 /**
6297  * @brief Auto Connection Establishment - Stop Connecting to device
6298  * @param address_typ
6299  * @param address
6300  * @returns 0 if ok
6301  */
6302 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6303     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6304         return ERROR_CODE_COMMAND_DISALLOWED;
6305     }
6306 
6307     hci_whitelist_remove(address_type, address);
6308     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6309         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6310     }
6311     hci_run();
6312     return 0;
6313 }
6314 
6315 /**
6316  * @brief Auto Connection Establishment - Stop everything
6317  * @note  Convenience function to stop all active auto connection attempts
6318  */
6319 uint8_t gap_auto_connection_stop_all(void){
6320     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6321         return ERROR_CODE_COMMAND_DISALLOWED;
6322     }
6323     hci_whitelist_clear();
6324     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6325     hci_run();
6326     return ERROR_CODE_SUCCESS;
6327 }
6328 
6329 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6330     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6331     if (!conn) return 0;
6332     return conn->le_connection_interval;
6333 }
6334 #endif
6335 #endif
6336 
6337 #ifdef ENABLE_CLASSIC
6338 /**
6339  * @brief Set Extended Inquiry Response data
6340  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6341  * @note has to be done before stack starts up
6342  */
6343 void gap_set_extended_inquiry_response(const uint8_t * data){
6344     hci_stack->eir_data = data;
6345     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6346     hci_run();
6347 }
6348 
6349 /**
6350  * @brief Start GAP Classic Inquiry
6351  * @param duration in 1.28s units
6352  * @return 0 if ok
6353  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6354  */
6355 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6356     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6357     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6358     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6359         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6360     }
6361     hci_stack->inquiry_state = duration_in_1280ms_units;
6362     hci_run();
6363     return 0;
6364 }
6365 
6366 /**
6367  * @brief Stop GAP Classic Inquiry
6368  * @returns 0 if ok
6369  */
6370 int gap_inquiry_stop(void){
6371     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6372         // emit inquiry complete event, before it even started
6373         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6374         hci_emit_event(event, sizeof(event), 1);
6375         return 0;
6376     }
6377     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6378     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6379     hci_run();
6380     return 0;
6381 }
6382 
6383 void gap_inquiry_set_lap(uint32_t lap){
6384     hci_stack->inquiry_lap = lap;
6385 }
6386 
6387 
6388 /**
6389  * @brief Remote Name Request
6390  * @param addr
6391  * @param page_scan_repetition_mode
6392  * @param clock_offset only used when bit 15 is set
6393  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6394  */
6395 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6396     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6397     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6398     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6399     hci_stack->remote_name_clock_offset = clock_offset;
6400     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6401     hci_run();
6402     return 0;
6403 }
6404 
6405 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6406     hci_stack->gap_pairing_state = state;
6407     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6408     hci_run();
6409     return 0;
6410 }
6411 
6412 /**
6413  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6414  * @param addr
6415  * @param pin_data
6416  * @param pin_len
6417  * @return 0 if ok
6418  */
6419 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6420     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6421     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6422     hci_stack->gap_pairing_pin_len = pin_len;
6423     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6424 }
6425 
6426 /**
6427  * @brief Legacy Pairing Pin Code Response
6428  * @param addr
6429  * @param pin
6430  * @return 0 if ok
6431  */
6432 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6433     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6434 }
6435 
6436 /**
6437  * @brief Abort Legacy Pairing
6438  * @param addr
6439  * @param pin
6440  * @return 0 if ok
6441  */
6442 int gap_pin_code_negative(bd_addr_t addr){
6443     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6444     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6445 }
6446 
6447 /**
6448  * @brief SSP Passkey Response
6449  * @param addr
6450  * @param passkey
6451  * @return 0 if ok
6452  */
6453 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6454     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6455     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6456     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6457 }
6458 
6459 /**
6460  * @brief Abort SSP Passkey Entry/Pairing
6461  * @param addr
6462  * @param pin
6463  * @return 0 if ok
6464  */
6465 int gap_ssp_passkey_negative(const bd_addr_t addr){
6466     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6467     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6468 }
6469 
6470 /**
6471  * @brief Accept SSP Numeric Comparison
6472  * @param addr
6473  * @param passkey
6474  * @return 0 if ok
6475  */
6476 int gap_ssp_confirmation_response(const bd_addr_t addr){
6477     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6478     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6479 }
6480 
6481 /**
6482  * @brief Abort SSP Numeric Comparison/Pairing
6483  * @param addr
6484  * @param pin
6485  * @return 0 if ok
6486  */
6487 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6488     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6489     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6490 }
6491 
6492 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6493 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6494     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6495     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6496     connectionSetAuthenticationFlags(conn, flag);
6497     hci_run();
6498     return ERROR_CODE_SUCCESS;
6499 }
6500 #endif
6501 
6502 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6503 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6504     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6505 }
6506 
6507 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6508     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6509 }
6510 #endif
6511 
6512 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6513 /**
6514  * @brief Report Remote OOB Data
6515  * @param bd_addr
6516  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6517  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6518  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6519  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6520  */
6521 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){
6522     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6523     if (connection == NULL) {
6524         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6525     }
6526     connection->classic_oob_c_192 = c_192;
6527     connection->classic_oob_r_192 = r_192;
6528 
6529     // ignore P-256 if not supported by us
6530     if (hci_stack->secure_connections_active){
6531         connection->classic_oob_c_256 = c_256;
6532         connection->classic_oob_r_256 = r_256;
6533     }
6534 
6535     return ERROR_CODE_SUCCESS;
6536 }
6537 /**
6538  * @brief Generate new OOB data
6539  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6540  */
6541 void gap_ssp_generate_oob_data(void){
6542     hci_stack->classic_read_local_oob_data = true;
6543     hci_run();
6544 }
6545 
6546 #endif
6547 
6548 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6549 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6550     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6551     if (connection == NULL) {
6552         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6553     }
6554 
6555     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6556     connection->link_key_type = type;
6557 
6558     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6559 }
6560 
6561 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6562 /**
6563  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6564  * @param inquiry_mode see bluetooth_defines.h
6565  */
6566 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6567     hci_stack->inquiry_mode = inquiry_mode;
6568 }
6569 
6570 /**
6571  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6572  */
6573 void hci_set_sco_voice_setting(uint16_t voice_setting){
6574     hci_stack->sco_voice_setting = voice_setting;
6575 }
6576 
6577 /**
6578  * @brief Get SCO Voice Setting
6579  * @return current voice setting
6580  */
6581 uint16_t hci_get_sco_voice_setting(void){
6582     return hci_stack->sco_voice_setting;
6583 }
6584 
6585 static int hci_have_usb_transport(void){
6586     if (!hci_stack->hci_transport) return 0;
6587     const char * transport_name = hci_stack->hci_transport->name;
6588     if (!transport_name) return 0;
6589     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6590 }
6591 
6592 /** @brief Get SCO packet length for current SCO Voice setting
6593  *  @note  Using SCO packets of the exact length is required for USB transfer
6594  *  @return Length of SCO packets in bytes (not audio frames)
6595  */
6596 uint16_t hci_get_sco_packet_length(void){
6597     uint16_t sco_packet_length = 0;
6598 
6599 #ifdef ENABLE_SCO_OVER_HCI
6600     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6601     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6602 
6603     if (hci_have_usb_transport()){
6604         // see Core Spec for H2 USB Transfer.
6605         // 3 byte SCO header + 24 bytes per connection
6606         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6607         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6608     } else {
6609         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6610         sco_packet_length = 3 + 60 * multiplier;
6611         // assert that it still fits inside an SCO buffer
6612         if (sco_packet_length > hci_stack->sco_data_packet_length){
6613             sco_packet_length = 3 + 60;
6614         }
6615     }
6616 #endif
6617 
6618 #ifdef HAVE_SCO_TRANSPORT
6619     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6620     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6621     sco_packet_length = 3 + 60 * multiplier;
6622 #endif
6623     return sco_packet_length;
6624 }
6625 
6626 /**
6627 * @brief Sets the master/slave policy
6628 * @param policy (0: attempt to become master, 1: let connecting device decide)
6629 */
6630 void hci_set_master_slave_policy(uint8_t policy){
6631     hci_stack->master_slave_policy = policy;
6632 }
6633 
6634 #endif
6635 
6636 HCI_STATE hci_get_state(void){
6637     return hci_stack->state;
6638 }
6639 
6640 #ifdef ENABLE_CLASSIC
6641 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6642     hci_stack->gap_classic_accept_callback = accept_callback;
6643 }
6644 #endif
6645 
6646 /**
6647  * @brief Set callback for Bluetooth Hardware Error
6648  */
6649 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6650     hci_stack->hardware_error_callback = fn;
6651 }
6652 
6653 void hci_disconnect_all(void){
6654     btstack_linked_list_iterator_t it;
6655     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6656     while (btstack_linked_list_iterator_has_next(&it)){
6657         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6658         if (con->state == SENT_DISCONNECT) continue;
6659         con->state = SEND_DISCONNECT;
6660     }
6661     hci_run();
6662 }
6663 
6664 uint16_t hci_get_manufacturer(void){
6665     return hci_stack->manufacturer;
6666 }
6667 
6668 #ifdef ENABLE_BLE
6669 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6670     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6671     if (!hci_con) return NULL;
6672     return &hci_con->sm_connection;
6673 }
6674 
6675 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6676 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6677 #endif
6678 
6679 int gap_encryption_key_size(hci_con_handle_t con_handle){
6680     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6681     if (hci_connection == NULL) return 0;
6682     if (hci_is_le_connection(hci_connection)){
6683 #ifdef ENABLE_BLE
6684         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6685         if (sm_conn->sm_connection_encrypted) {
6686             return sm_conn->sm_actual_encryption_key_size;
6687         }
6688 #endif
6689     } else {
6690 #ifdef ENABLE_CLASSIC
6691         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6692             return hci_connection->encryption_key_size;
6693         }
6694 #endif
6695     }
6696     return 0;
6697 }
6698 
6699 int gap_authenticated(hci_con_handle_t con_handle){
6700     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6701     if (hci_connection == NULL) return 0;
6702 
6703     switch (hci_connection->address_type){
6704 #ifdef ENABLE_BLE
6705         case BD_ADDR_TYPE_LE_PUBLIC:
6706         case BD_ADDR_TYPE_LE_RANDOM:
6707             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6708             return hci_connection->sm_connection.sm_connection_authenticated;
6709 #endif
6710 #ifdef ENABLE_CLASSIC
6711         case BD_ADDR_TYPE_SCO:
6712         case BD_ADDR_TYPE_ACL:
6713             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6714 #endif
6715         default:
6716             return 0;
6717     }
6718 }
6719 
6720 int gap_secure_connection(hci_con_handle_t con_handle){
6721     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6722     if (hci_connection == NULL) return 0;
6723 
6724     switch (hci_connection->address_type){
6725 #ifdef ENABLE_BLE
6726         case BD_ADDR_TYPE_LE_PUBLIC:
6727         case BD_ADDR_TYPE_LE_RANDOM:
6728             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6729             return hci_connection->sm_connection.sm_connection_sc;
6730 #endif
6731 #ifdef ENABLE_CLASSIC
6732         case BD_ADDR_TYPE_SCO:
6733         case BD_ADDR_TYPE_ACL:
6734             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6735 #endif
6736         default:
6737             return 0;
6738     }
6739 }
6740 
6741 bool gap_bonded(hci_con_handle_t con_handle){
6742 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6743 	if (hci_connection == NULL) return 0;
6744 
6745 #ifdef ENABLE_CLASSIC
6746 	link_key_t link_key;
6747 	link_key_type_t link_key_type;
6748 #endif
6749 	switch (hci_connection->address_type){
6750 #ifdef ENABLE_BLE
6751 		case BD_ADDR_TYPE_LE_PUBLIC:
6752 		case BD_ADDR_TYPE_LE_RANDOM:
6753 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6754 #endif
6755 #ifdef ENABLE_CLASSIC
6756 		case BD_ADDR_TYPE_SCO:
6757 		case BD_ADDR_TYPE_ACL:
6758 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6759 #endif
6760 		default:
6761 			return false;
6762 	}
6763 }
6764 
6765 #ifdef ENABLE_BLE
6766 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6767     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6768     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6769     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6770     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6771     return sm_conn->sm_connection_authorization_state;
6772 }
6773 #endif
6774 
6775 #ifdef ENABLE_CLASSIC
6776 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){
6777     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6778     if (!conn) return GAP_CONNECTION_INVALID;
6779     conn->sniff_min_interval = sniff_min_interval;
6780     conn->sniff_max_interval = sniff_max_interval;
6781     conn->sniff_attempt = sniff_attempt;
6782     conn->sniff_timeout = sniff_timeout;
6783     hci_run();
6784     return 0;
6785 }
6786 
6787 /**
6788  * @brief Exit Sniff mode
6789  * @param con_handle
6790  @ @return 0 if ok
6791  */
6792 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6793     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6794     if (!conn) return GAP_CONNECTION_INVALID;
6795     conn->sniff_min_interval = 0xffff;
6796     hci_run();
6797     return 0;
6798 }
6799 
6800 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){
6801     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6802     if (!conn) return GAP_CONNECTION_INVALID;
6803     conn->sniff_subrating_max_latency = max_latency;
6804     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6805     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6806     hci_run();
6807     return ERROR_CODE_SUCCESS;
6808 }
6809 
6810 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){
6811     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6812     if (!conn) return GAP_CONNECTION_INVALID;
6813     conn->qos_service_type = service_type;
6814     conn->qos_token_rate = token_rate;
6815     conn->qos_peak_bandwidth = peak_bandwidth;
6816     conn->qos_latency = latency;
6817     conn->qos_delay_variation = delay_variation;
6818     hci_run();
6819     return ERROR_CODE_SUCCESS;
6820 }
6821 
6822 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6823     hci_stack->new_page_scan_interval = page_scan_interval;
6824     hci_stack->new_page_scan_window = page_scan_window;
6825     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6826     hci_run();
6827 }
6828 
6829 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6830     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6831     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6832     hci_run();
6833 }
6834 
6835 #endif
6836 
6837 void hci_halting_defer(void){
6838     if (hci_stack->state != HCI_STATE_HALTING) return;
6839     switch (hci_stack->substate){
6840         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6841         case HCI_HALTING_CLOSE:
6842             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6843             break;
6844         default:
6845             break;
6846     }
6847 }
6848 
6849 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6850 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6851     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6852     if (le_device_db_index >= le_device_db_max_count()) return;
6853     uint8_t offset = le_device_db_index >> 3;
6854     uint8_t mask = 1 << (le_device_db_index & 7);
6855     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6856     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6857     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6858         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6859     }
6860 }
6861 
6862 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6863 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6864 	if (le_device_db_index >= le_device_db_max_count()) return;
6865 	uint8_t offset = le_device_db_index >> 3;
6866 	uint8_t mask = 1 << (le_device_db_index & 7);
6867 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6868 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6869 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6870 	}
6871 }
6872 
6873 uint8_t gap_load_resolving_list_from_le_device_db(void){
6874 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6875 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6876 	}
6877 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6878 		// restart le resolving list update
6879 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6880 	}
6881 	return ERROR_CODE_SUCCESS;
6882 }
6883 #endif
6884 
6885 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6886 void hci_setup_test_connections_fuzz(void){
6887     hci_connection_t * conn;
6888 
6889     // default address: 66:55:44:33:00:01
6890     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6891 
6892     // setup Controller info
6893     hci_stack->num_cmd_packets = 255;
6894     hci_stack->acl_packets_total_num = 255;
6895 
6896     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6897     addr[5] = 0x01;
6898     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6899     conn->con_handle = addr[5];
6900     conn->role  = HCI_ROLE_SLAVE;
6901     conn->state = RECEIVED_CONNECTION_REQUEST;
6902     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6903 
6904     // setup incoming Classic SCO connection with con handle 0x0002
6905     addr[5] = 0x02;
6906     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6907     conn->con_handle = addr[5];
6908     conn->role  = HCI_ROLE_SLAVE;
6909     conn->state = RECEIVED_CONNECTION_REQUEST;
6910     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6911 
6912     // setup ready Classic ACL connection with con handle 0x0003
6913     addr[5] = 0x03;
6914     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6915     conn->con_handle = addr[5];
6916     conn->role  = HCI_ROLE_SLAVE;
6917     conn->state = OPEN;
6918     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6919 
6920     // setup ready Classic SCO connection with con handle 0x0004
6921     addr[5] = 0x04;
6922     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6923     conn->con_handle = addr[5];
6924     conn->role  = HCI_ROLE_SLAVE;
6925     conn->state = OPEN;
6926     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6927 
6928     // setup ready LE ACL connection with con handle 0x005 and public address
6929     addr[5] = 0x05;
6930     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6931     conn->con_handle = addr[5];
6932     conn->role  = HCI_ROLE_SLAVE;
6933     conn->state = OPEN;
6934     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6935     conn->sm_connection.sm_connection_encrypted = 1;
6936 }
6937 
6938 void hci_free_connections_fuzz(void){
6939     btstack_linked_list_iterator_t it;
6940     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6941     while (btstack_linked_list_iterator_has_next(&it)){
6942         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6943         btstack_linked_list_iterator_remove(&it);
6944         btstack_memory_hci_connection_free(con);
6945     }
6946 }
6947 void hci_simulate_working_fuzz(void){
6948     hci_init_done();
6949     hci_stack->num_cmd_packets = 255;
6950 }
6951 #endif
6952