xref: /btstack/src/hci.c (revision d6596031ae576ad9f7b3aa7e1891e1134919a11c)
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     bool need_baud_change = false;
1438 
1439 #ifndef HAVE_HOST_CONTROLLER_API
1440     need_baud_change = hci_stack->config
1441             && hci_stack->chipset
1442             && hci_stack->chipset->set_baudrate_command
1443             && hci_stack->hci_transport->set_baudrate
1444             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1445 #endif
1446 
1447     switch (hci_stack->substate){
1448         case HCI_INIT_SEND_RESET:
1449             hci_state_reset();
1450 
1451 #ifndef HAVE_HOST_CONTROLLER_API
1452             // prepare reset if command complete not received in 100ms
1453             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1454             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1455             btstack_run_loop_add_timer(&hci_stack->timeout);
1456 #endif
1457             // send command
1458             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1459             hci_send_cmd(&hci_reset);
1460             break;
1461         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1462             hci_send_cmd(&hci_read_local_version_information);
1463             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1464             break;
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 
1470 #ifndef HAVE_HOST_CONTROLLER_API
1471         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1472             hci_state_reset();
1473             // prepare reset if command complete not received in 100ms
1474             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1475             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1476             btstack_run_loop_add_timer(&hci_stack->timeout);
1477             // send command
1478             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1479             hci_send_cmd(&hci_reset);
1480             break;
1481         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1482             hci_state_reset();
1483             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1484             hci_send_cmd(&hci_reset);
1485             break;
1486         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1487             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1488             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1489             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1490             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1491             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1492             break;
1493         }
1494         case HCI_INIT_SET_BD_ADDR:
1495             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1496             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1497             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1498             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1499             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1500             break;
1501         case HCI_INIT_SEND_BAUD_CHANGE:
1502             if (need_baud_change) {
1503                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1504                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1505                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1506                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1507                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1508                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1509                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1510                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1511                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1512                     btstack_run_loop_add_timer(&hci_stack->timeout);
1513                }
1514                break;
1515             }
1516 
1517             /* fall through */
1518 
1519         case HCI_INIT_CUSTOM_INIT:
1520             // Custom initialization
1521             if (hci_stack->chipset && hci_stack->chipset->next_command){
1522                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1523                 bool send_cmd = false;
1524                 switch (hci_stack->chipset_result){
1525                     case BTSTACK_CHIPSET_VALID_COMMAND:
1526                         send_cmd = true;
1527                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1528                         break;
1529                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1530                         send_cmd = true;
1531                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1532                         log_info("CSR Warm Boot");
1533                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1534                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1535                         btstack_run_loop_add_timer(&hci_stack->timeout);
1536                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1537                             && hci_stack->config
1538                             && hci_stack->chipset
1539                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1540                             && hci_stack->hci_transport->set_baudrate
1541                             && hci_transport_uart_get_main_baud_rate()){
1542                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1543                         } else {
1544                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1545                         }
1546                         break;
1547                     default:
1548                         break;
1549                 }
1550 
1551                 if (send_cmd){
1552                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1553                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1554                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1555                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1556                     break;
1557                 }
1558                 log_info("Init script done");
1559 
1560                 // Init script download on Broadcom chipsets causes:
1561                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1562                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1563                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1564 
1565                     // - baud rate to reset, restore UART baud rate if needed
1566                     if (need_baud_change) {
1567                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1568                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1569                         hci_stack->hci_transport->set_baudrate(baud_rate);
1570                     }
1571 
1572                     uint16_t bcm_delay_ms = 300;
1573                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1574                     //   -> Work around: wait here.
1575                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1576                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1577                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1578                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1579                     btstack_run_loop_add_timer(&hci_stack->timeout);
1580                     break;
1581                 }
1582             }
1583             /* fall through */
1584 #endif
1585 
1586         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1587             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1588             hci_send_cmd(&hci_read_local_supported_commands);
1589             break;
1590         case HCI_INIT_READ_BD_ADDR:
1591             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1592             hci_send_cmd(&hci_read_bd_addr);
1593             break;
1594         case HCI_INIT_READ_BUFFER_SIZE:
1595             // only read buffer size if supported
1596             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1597                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1598                 hci_send_cmd(&hci_read_buffer_size);
1599                 break;
1600             }
1601             /* fall through */
1602 
1603         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1604             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1605             hci_send_cmd(&hci_read_local_supported_features);
1606             break;
1607 
1608 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1609         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1610             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1611             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1612             break;
1613         case HCI_INIT_HOST_BUFFER_SIZE:
1614             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1615             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1616                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1617             break;
1618 #endif
1619 
1620         case HCI_INIT_SET_EVENT_MASK:
1621             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1622             if (hci_le_supported()){
1623                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1624             } else {
1625                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1626                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1627             }
1628             break;
1629 
1630 #ifdef ENABLE_CLASSIC
1631         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1632             if (hci_classic_supported() && gap_ssp_supported()){
1633                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1634                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1635                 break;
1636             }
1637             /* fall through */
1638 
1639         case HCI_INIT_WRITE_INQUIRY_MODE:
1640             if (hci_classic_supported()){
1641                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1642                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1643                 break;
1644             }
1645             /* fall through */
1646 
1647         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1648             // skip write secure connections host support if not supported or disabled
1649             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1650                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1651                 hci_stack->secure_connections_active = true;
1652                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1653                 break;
1654             }
1655             /* fall through */
1656 
1657         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1658             if (hci_classic_supported()){
1659                 hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1660                 hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1661                 break;
1662             }
1663             /* fall through */
1664 
1665 #ifdef ENABLE_SCO_OVER_HCI
1666         // only sent if ENABLE_SCO_OVER_HCI is defined
1667         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1668             // skip write synchronous flow control if not supported
1669             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1670                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1671                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1672                 break;
1673             }
1674             /* fall through */
1675 
1676         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1677             // skip write default erroneous data reporting if not supported
1678             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1679                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1680                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1681                 break;
1682             }
1683             /* fall through */
1684 #endif
1685 
1686 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1687         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1688         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1689             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1690                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1691 #ifdef ENABLE_SCO_OVER_HCI
1692                 log_info("BCM: Route SCO data via HCI transport");
1693                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1694 #endif
1695 #ifdef ENABLE_SCO_OVER_PCM
1696                 log_info("BCM: Route SCO data via PCM interface");
1697 #ifdef ENABLE_BCM_PCM_WBS
1698                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1699                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1700 #else
1701                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1702                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1703 #endif
1704 #endif
1705                 break;
1706             }
1707             /* fall through */
1708 #endif
1709 
1710 #ifdef ENABLE_SCO_OVER_PCM
1711         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1712             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1713                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1714                 log_info("BCM: Config PCM interface for I2S");
1715 #ifdef ENABLE_BCM_PCM_WBS
1716                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1717                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1718 #else
1719                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1720                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1721 #endif
1722                 break;
1723             }
1724             /* fall through */
1725 #endif
1726 #endif
1727 
1728 #ifdef ENABLE_BLE
1729         // LE INIT
1730         case HCI_INIT_LE_READ_BUFFER_SIZE:
1731             if (hci_le_supported()){
1732                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1733                 hci_send_cmd(&hci_le_read_buffer_size);
1734                 break;
1735             }
1736             /* fall through */
1737 
1738         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1739             // skip write le host if not supported (e.g. on LE only EM9301)
1740             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1741                 // LE Supported Host = 1, Simultaneous Host = 0
1742                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1743                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1744                 break;
1745             }
1746             /* fall through */
1747 
1748         case HCI_INIT_LE_SET_EVENT_MASK:
1749             if (hci_le_supported()){
1750                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1751                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1752                 break;
1753             }
1754             /* fall through */
1755 
1756 #endif
1757 
1758 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1759         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1760             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1761                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1762                 hci_send_cmd(&hci_le_read_maximum_data_length);
1763                 break;
1764             }
1765             /* fall through */
1766 
1767         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1768             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1769                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1770                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1771                 break;
1772             }
1773             /* fall through */
1774 #endif
1775 
1776 #ifdef ENABLE_LE_CENTRAL
1777         case HCI_INIT_READ_WHITE_LIST_SIZE:
1778             if (hci_le_supported()){
1779                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1780                 hci_send_cmd(&hci_le_read_white_list_size);
1781                 break;
1782             }
1783             /* fall through */
1784 
1785         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1786             if (hci_le_supported()){
1787                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1788                 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);
1789                 break;
1790             }
1791             /* fall through */
1792 #endif
1793 
1794         case HCI_INIT_DONE:
1795             hci_stack->substate = HCI_INIT_DONE;
1796 #ifdef ENABLE_CLASSIC
1797             // init sequence complete, check if GAP Tasks are completed
1798             if (hci_stack->gap_tasks != 0) {
1799                 hci_run_gap_tasks_classic();
1800                 break;
1801             }
1802 #endif
1803             hci_init_done();
1804             break;
1805 
1806         default:
1807             return;
1808     }
1809 }
1810 
1811 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1812     bool command_completed = false;
1813     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1814         uint16_t opcode = little_endian_read_16(packet,3);
1815         if (opcode == hci_stack->last_cmd_opcode){
1816             command_completed = true;
1817             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1818         } else {
1819             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1820         }
1821     }
1822 
1823     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1824         uint8_t  status = packet[2];
1825         uint16_t opcode = little_endian_read_16(packet,4);
1826         if (opcode == hci_stack->last_cmd_opcode){
1827             if (status){
1828                 command_completed = true;
1829                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1830             } else {
1831                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1832             }
1833         } else {
1834             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1835         }
1836     }
1837 #ifndef HAVE_HOST_CONTROLLER_API
1838     // Vendor == CSR
1839     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1840         // TODO: track actual command
1841         command_completed = true;
1842     }
1843 
1844     // Vendor == Toshiba
1845     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1846         // TODO: track actual command
1847         command_completed = true;
1848         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1849         hci_stack->num_cmd_packets = 1;
1850     }
1851 #endif
1852 
1853     return command_completed;
1854 }
1855 
1856 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1857 
1858     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1859 
1860     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1861 
1862 #ifndef HAVE_HOST_CONTROLLER_API
1863 
1864     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1865     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1866     //
1867     // HCI Reset
1868     // Timeout 100 ms
1869     // HCI Reset
1870     // Command Complete Reset
1871     // HCI Read Local Version Information
1872     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1873     // hang...
1874     //
1875     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1876     if (!command_completed
1877             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1878             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1879 
1880         uint16_t opcode = little_endian_read_16(packet,3);
1881         if (opcode == hci_reset.opcode){
1882             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1883             return;
1884         }
1885     }
1886 
1887     // CSR & H5
1888     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1889     if (!command_completed
1890             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1891             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1892 
1893         uint16_t opcode = little_endian_read_16(packet,3);
1894         if (opcode == hci_reset.opcode){
1895             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1896             return;
1897         }
1898     }
1899 
1900     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1901     // fix: Correct substate and behave as command below
1902     if (command_completed){
1903         switch (hci_stack->substate){
1904             case HCI_INIT_SEND_RESET:
1905                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1906                 break;
1907             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1908                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1909                 break;
1910             default:
1911                 break;
1912         }
1913     }
1914 
1915 #endif
1916 
1917     if (!command_completed) return;
1918 
1919     bool need_baud_change = false;
1920     bool need_addr_change = false;
1921 
1922 #ifndef HAVE_HOST_CONTROLLER_API
1923     need_baud_change = hci_stack->config
1924                         && hci_stack->chipset
1925                         && hci_stack->chipset->set_baudrate_command
1926                         && hci_stack->hci_transport->set_baudrate
1927                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1928 
1929     need_addr_change = hci_stack->custom_bd_addr_set
1930                         && hci_stack->chipset
1931                         && hci_stack->chipset->set_bd_addr_command;
1932 #endif
1933 
1934     switch(hci_stack->substate){
1935 
1936 #ifndef HAVE_HOST_CONTROLLER_API
1937         case HCI_INIT_SEND_RESET:
1938             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1939             // fix: just correct substate and behave as command below
1940 
1941             /* fall through */
1942 #endif
1943 
1944         case HCI_INIT_W4_SEND_RESET:
1945             btstack_run_loop_remove_timer(&hci_stack->timeout);
1946             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1947             return;
1948 
1949 #ifndef HAVE_HOST_CONTROLLER_API
1950         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1951             // for STLC2500D, baud rate change already happened.
1952             // for others, baud rate gets changed now
1953             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1954                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1955                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1956                 hci_stack->hci_transport->set_baudrate(baud_rate);
1957             }
1958             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1959             return;
1960         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1961             btstack_run_loop_remove_timer(&hci_stack->timeout);
1962             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1963             return;
1964         case HCI_INIT_W4_CUSTOM_INIT:
1965             // repeat custom init
1966             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1967             return;
1968 #endif
1969 
1970         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1971             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1972               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1973                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1974                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1975                 return;
1976             }
1977             if (need_addr_change){
1978                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1979                 return;
1980             }
1981             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1982             return;
1983 #ifndef HAVE_HOST_CONTROLLER_API
1984         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1985             if (need_baud_change){
1986                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1987                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1988                 hci_stack->hci_transport->set_baudrate(baud_rate);
1989             }
1990             if (need_addr_change){
1991                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1992                 return;
1993             }
1994             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1995             return;
1996         case HCI_INIT_W4_SET_BD_ADDR:
1997             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1998             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1999             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2000                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2001                 return;
2002             }
2003             // skipping st warm boot
2004             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2005             return;
2006         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2007             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2008             return;
2009 #endif
2010 
2011         case HCI_INIT_DONE:
2012             // set state if we came here by fall through
2013             hci_stack->substate = HCI_INIT_DONE;
2014             return;
2015 
2016         default:
2017             break;
2018     }
2019     hci_initializing_next_state();
2020 }
2021 
2022 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2023     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2024     bd_addr_t bd_address;
2025     (void)memcpy(&bd_address, conn->address, 6);
2026 
2027 #ifdef ENABLE_CLASSIC
2028     // cache needed data
2029     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2030 #endif
2031 
2032     // connection failed, remove entry
2033     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2034     btstack_memory_hci_connection_free( conn );
2035 
2036 #ifdef ENABLE_CLASSIC
2037     // notify client if dedicated bonding
2038     if (notify_dedicated_bonding_failed){
2039         log_info("hci notify_dedicated_bonding_failed");
2040         hci_emit_dedicated_bonding_result(bd_address, status);
2041     }
2042 
2043     // if authentication error, also delete link key
2044     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2045         gap_drop_link_key_for_bd_addr(bd_address);
2046     }
2047 #else
2048     UNUSED(status);
2049 #endif
2050 }
2051 
2052 #ifdef ENABLE_CLASSIC
2053 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2054     // SSP Controller
2055     if (features[6] & (1 << 3)){
2056         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2057     }
2058     // eSCO
2059     if (features[3] & (1<<7)){
2060         conn->remote_supported_features[0] |= 1;
2061     }
2062     // Extended features
2063     if (features[7] & (1<<7)){
2064         conn->remote_supported_features[0] |= 2;
2065     }
2066 }
2067 
2068 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2069     // SSP Host
2070     if (features[0] & (1 << 0)){
2071         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2072     }
2073     // SC Host
2074     if (features[0] & (1 << 3)){
2075         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2076     }
2077 }
2078 
2079 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2080     // SC Controller
2081     if (features[1] & (1 << 0)){
2082         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2083     }
2084 }
2085 
2086 static void hci_handle_remote_features_received(hci_connection_t * conn){
2087     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2088     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2089     if (conn->bonding_flags & BONDING_DEDICATED){
2090         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2091     }
2092 }
2093 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2094     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2095     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2096 }
2097 
2098 #endif
2099 
2100 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2101     // handle BT initialization
2102     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2103         hci_initializing_event_handler(packet, size);
2104     }
2105 
2106     // help with BT sleep
2107     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2108         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2109         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2110         hci_initializing_next_state();
2111     }
2112 }
2113 
2114 #ifdef ENABLE_CLASSIC
2115 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2116     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2117     conn->encryption_key_size = encryption_key_size;
2118 
2119     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2120         conn->requested_security_level = LEVEL_0;
2121         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2122         return;
2123     }
2124 
2125     // Request Authentication if not already done
2126     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2127     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2128 }
2129 #endif
2130 
2131 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2132     UNUSED(size);
2133 
2134     uint16_t manufacturer;
2135 #ifdef ENABLE_CLASSIC
2136     hci_con_handle_t handle;
2137     hci_connection_t * conn;
2138     uint8_t status;
2139 #endif
2140     // get num cmd packets - limit to 1 to reduce complexity
2141     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2142 
2143     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2144     switch (opcode){
2145         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2146             if (packet[5]) break;
2147             // terminate, name 248 chars
2148             packet[6+248] = 0;
2149             log_info("local name: %s", &packet[6]);
2150             break;
2151         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2152             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2153             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2154                 uint16_t acl_len = little_endian_read_16(packet, 6);
2155                 uint16_t sco_len = packet[8];
2156 
2157                 // determine usable ACL/SCO payload size
2158                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2159                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2160 
2161                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2162                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2163 
2164                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2165                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2166                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2167             }
2168             break;
2169         case HCI_OPCODE_HCI_READ_RSSI:
2170             if (packet[5] == ERROR_CODE_SUCCESS){
2171                 uint8_t event[5];
2172                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2173                 event[1] = 3;
2174                 (void)memcpy(&event[2], &packet[6], 3);
2175                 hci_emit_event(event, sizeof(event), 1);
2176             }
2177             break;
2178 #ifdef ENABLE_BLE
2179         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2180             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2181             hci_stack->le_acl_packets_total_num = packet[8];
2182             // determine usable ACL payload size
2183             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2184                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2185             }
2186             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2187             break;
2188 #endif
2189 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2190         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2191             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2192             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2193             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);
2194             break;
2195 #endif
2196 #ifdef ENABLE_LE_CENTRAL
2197         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2198             hci_stack->le_whitelist_capacity = packet[6];
2199             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2200             break;
2201 #endif
2202         case HCI_OPCODE_HCI_READ_BD_ADDR:
2203             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2204             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));
2205 #ifdef ENABLE_CLASSIC
2206             if (hci_stack->link_key_db){
2207                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2208             }
2209 #endif
2210             break;
2211 #ifdef ENABLE_CLASSIC
2212         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2213             hci_emit_discoverable_enabled(hci_stack->discoverable);
2214             break;
2215         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2216             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2217                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2218                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2219                 hci_emit_event(event, sizeof(event), 1);
2220             }
2221             break;
2222 #endif
2223         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2224             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2225 
2226 #ifdef ENABLE_CLASSIC
2227             // determine usable ACL packet types based on host buffer size and supported features
2228             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2229             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2230 #endif
2231             // Classic/LE
2232             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2233             break;
2234         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2235             manufacturer = little_endian_read_16(packet, 10);
2236             // map Cypress to Broadcom
2237             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2238                 log_info("Treat Cypress as Broadcom");
2239                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2240                 little_endian_store_16(packet, 10, manufacturer);
2241             }
2242             hci_stack->manufacturer = manufacturer;
2243             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2244             break;
2245         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2246             hci_stack->local_supported_commands[0] =
2247                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2248                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2249                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2250                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2251                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2252                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2253                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2254                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2255             hci_stack->local_supported_commands[1] =
2256                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2257                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2258                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2259                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2260                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2261             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2262             break;
2263 #ifdef ENABLE_CLASSIC
2264         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2265             if (packet[5]) return;
2266             hci_stack->synchronous_flow_control_enabled = 1;
2267             break;
2268         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2269             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2270             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2271             conn   = hci_connection_for_handle(handle);
2272             if (conn != NULL) {
2273                 uint8_t key_size = 0;
2274                 if (status == 0){
2275                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2276                     log_info("Handle %04x key Size: %u", handle, key_size);
2277                 } else {
2278                     key_size = 1;
2279                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2280                 }
2281                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2282             }
2283             break;
2284         // assert pairing complete event is emitted.
2285         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2286         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2287         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2288         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2289             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2290             // lookup connection by gap pairing addr
2291             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2292             if (conn == NULL) break;
2293             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2294             break;
2295 
2296 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2297         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2298         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2299             uint8_t event[67];
2300             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2301             event[1] = 65;
2302             (void)memset(&event[2], 0, 65);
2303             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2304                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2305                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2306                     event[2] = 3;
2307                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2308                 } else {
2309                     event[2] = 1;
2310                 }
2311             }
2312             hci_emit_event(event, sizeof(event), 0);
2313             break;
2314         }
2315 
2316         // note: only needed if user does not provide OOB data
2317         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2318             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2319             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2320             if (conn == NULL) break;
2321             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2322             break;
2323 #endif
2324 #endif
2325         default:
2326             break;
2327     }
2328 }
2329 
2330 #ifdef ENABLE_BLE
2331 static void event_handle_le_connection_complete(const uint8_t * packet){
2332 	bd_addr_t addr;
2333 	bd_addr_type_t addr_type;
2334 	hci_connection_t * conn;
2335 
2336 	// Connection management
2337 	reverse_bd_addr(&packet[8], addr);
2338 	addr_type = (bd_addr_type_t)packet[7];
2339 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2340 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2341 
2342 #ifdef ENABLE_LE_CENTRAL
2343 	// handle error: error is reported only to the initiator -> outgoing connection
2344 	if (packet[3]){
2345 
2346 		// handle cancelled outgoing connection
2347 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2348 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2349 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2350 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2351 		    // reset state
2352             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2353             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2354 			// get outgoing connection conn struct for direct connect
2355 			conn = gap_get_outgoing_connection();
2356 		}
2357 
2358 		// outgoing le connection establishment is done
2359 		if (conn){
2360 			// remove entry
2361 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2362 			btstack_memory_hci_connection_free( conn );
2363 		}
2364 		return;
2365 	}
2366 #endif
2367 
2368 	// on success, both hosts receive connection complete event
2369 	if (packet[6] == HCI_ROLE_MASTER){
2370 #ifdef ENABLE_LE_CENTRAL
2371 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2372 		// note: no hci_connection_t object exists yet for connect with whitelist
2373 		if (hci_is_le_connection_type(addr_type)){
2374 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2375 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2376 		}
2377 #endif
2378 	} else {
2379 #ifdef ENABLE_LE_PERIPHERAL
2380 		// if we're slave, it was an incoming connection, advertisements have stopped
2381 		hci_stack->le_advertisements_active = false;
2382 #endif
2383 	}
2384 
2385 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2386 	if (!conn){
2387 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2388 	}
2389 
2390 	// no memory, sorry.
2391 	if (!conn){
2392 		return;
2393 	}
2394 
2395 	conn->state = OPEN;
2396 	conn->role  = packet[6];
2397 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2398 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2399 
2400 #ifdef ENABLE_LE_PERIPHERAL
2401 	if (packet[6] == HCI_ROLE_SLAVE){
2402 		hci_update_advertisements_enabled_for_current_roles();
2403 	}
2404 #endif
2405 
2406     // init unenhanced att bearer mtu
2407     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2408     conn->att_connection.mtu_exchanged = false;
2409 
2410     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2411 
2412 	// restart timer
2413 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2414 	// btstack_run_loop_add_timer(&conn->timeout);
2415 
2416 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2417 
2418 	hci_emit_nr_connections_changed();
2419 }
2420 #endif
2421 
2422 #ifdef ENABLE_CLASSIC
2423 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){
2424     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2425     // LEVEL_4 is tested by l2cap
2426     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2427     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2428     if (level >= LEVEL_3){
2429         // MITM not possible without keyboard or display
2430         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2431         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2432 
2433         // MITM possible if one side has keyboard and the other has keyboard or display
2434         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2435         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2436 
2437         // MITM not possible if one side has only display and other side has no keyboard
2438         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2439         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2440     }
2441     // LEVEL 2 requires SSP, which is a given
2442     return true;
2443 }
2444 
2445 static bool btstack_is_null(uint8_t * data, uint16_t size){
2446     uint16_t i;
2447     for (i=0; i < size ; i++){
2448         if (data[i] != 0) {
2449             return false;
2450         }
2451     }
2452     return true;
2453 }
2454 
2455 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2456     // get requested security level
2457     gap_security_level_t requested_security_level = conn->requested_security_level;
2458     if (hci_stack->gap_secure_connections_only_mode){
2459         requested_security_level = LEVEL_4;
2460     }
2461 
2462     // assess security: LEVEL 4 requires SC
2463     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2464     if ((requested_security_level == LEVEL_4) &&
2465         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2466         !hci_remote_sc_enabled(conn)){
2467         log_info("Level 4 required, but SC not supported -> abort");
2468         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2469         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2470         return;
2471     }
2472 
2473     // assess security based on io capabilities
2474     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2475         // responder: fully validate io caps of both sides as well as OOB data
2476         bool security_possible = false;
2477         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2478 
2479 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2480         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2481         // so we merge the OOB data availability
2482         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2483         if (conn->classic_oob_c_192 != NULL){
2484             have_oob_data |= 1;
2485         }
2486         if (conn->classic_oob_c_256 != NULL){
2487             have_oob_data |= 2;
2488         }
2489         // for up to Level 3, either P-192 as well as P-256 will do
2490         // 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
2491         // if remote does not SC, we should not receive P-256 data either
2492         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2493             security_possible = true;
2494         }
2495         // for Level 4, P-256 is needed
2496         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2497             security_possible = true;
2498         }
2499 #endif
2500 
2501         if (security_possible == false){
2502             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2503             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2504             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2505             return;
2506         }
2507     } else {
2508         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2509 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2510 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2511         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2512             log_info("Level 3+ required, but no input/output -> abort");
2513             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2514             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2515             return;
2516         }
2517 #endif
2518 #endif
2519     }
2520 
2521 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2522     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2523         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2524     } else {
2525         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2526     }
2527 #endif
2528 }
2529 
2530 #endif
2531 
2532 static void event_handler(uint8_t *packet, uint16_t size){
2533 
2534     uint16_t event_length = packet[1];
2535 
2536     // assert packet is complete
2537     if (size != (event_length + 2u)){
2538         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2539         return;
2540     }
2541 
2542     bd_addr_type_t addr_type;
2543     hci_con_handle_t handle;
2544     hci_connection_t * conn;
2545     int i;
2546     int create_connection_cmd;
2547 
2548 #ifdef ENABLE_CLASSIC
2549     hci_link_type_t link_type;
2550     bd_addr_t addr;
2551 #endif
2552 
2553     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2554 
2555     switch (hci_event_packet_get_type(packet)) {
2556 
2557         case HCI_EVENT_COMMAND_COMPLETE:
2558             handle_command_complete_event(packet, size);
2559             break;
2560 
2561         case HCI_EVENT_COMMAND_STATUS:
2562             // get num cmd packets - limit to 1 to reduce complexity
2563             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2564 
2565             // check command status to detected failed outgoing connections
2566             create_connection_cmd = 0;
2567 #ifdef ENABLE_CLASSIC
2568             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2569                 create_connection_cmd = 1;
2570             }
2571 #endif
2572 #ifdef ENABLE_LE_CENTRAL
2573             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2574                 create_connection_cmd = 1;
2575             }
2576 #endif
2577             if (create_connection_cmd) {
2578                 uint8_t status = hci_event_command_status_get_status(packet);
2579                 addr_type = hci_stack->outgoing_addr_type;
2580                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2581                 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);
2582 
2583                 // reset outgoing address info
2584                 memset(hci_stack->outgoing_addr, 0, 6);
2585                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2586 
2587                 // on error
2588                 if (status != ERROR_CODE_SUCCESS){
2589 #ifdef ENABLE_LE_CENTRAL
2590                     if (hci_is_le_connection_type(addr_type)){
2591                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2592                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2593                     }
2594 #endif
2595                     // error => outgoing connection failed
2596                     if (conn != NULL){
2597                         hci_handle_connection_failed(conn, status);
2598                     }
2599                 }
2600             }
2601 
2602 #ifdef ENABLE_CLASSIC
2603             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2604                 uint8_t status = hci_event_command_status_get_status(packet);
2605                 log_info("command status (inquiry), status %x", status);
2606                 if (status == ERROR_CODE_SUCCESS) {
2607                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2608                 } else {
2609                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2610                 }
2611             }
2612 #endif
2613             break;
2614 
2615         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2616             if (size < 3) return;
2617             uint16_t num_handles = packet[2];
2618             if (size != (3u + num_handles * 4u)) return;
2619             uint16_t offset = 3;
2620             for (i=0; i<num_handles;i++){
2621                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2622                 offset += 2u;
2623                 uint16_t num_packets = little_endian_read_16(packet, offset);
2624                 offset += 2u;
2625 
2626                 conn = hci_connection_for_handle(handle);
2627                 if (!conn){
2628                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2629                     continue;
2630                 }
2631 
2632                 if (conn->num_packets_sent >= num_packets){
2633                     conn->num_packets_sent -= num_packets;
2634                 } else {
2635                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2636                     conn->num_packets_sent = 0;
2637                 }
2638                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2639 
2640 #ifdef ENABLE_CLASSIC
2641                 // For SCO, we do the can_send_now_check here
2642                 hci_notify_if_sco_can_send_now();
2643 #endif
2644             }
2645             break;
2646         }
2647 
2648 #ifdef ENABLE_CLASSIC
2649         case HCI_EVENT_INQUIRY_COMPLETE:
2650             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2651                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2652                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2653                 hci_emit_event(event, sizeof(event), 1);
2654             }
2655             break;
2656         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2657             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2658                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2659             }
2660             break;
2661         case HCI_EVENT_CONNECTION_REQUEST:
2662             reverse_bd_addr(&packet[2], addr);
2663             link_type = (hci_link_type_t) packet[11];
2664 
2665             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2666             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2667                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2668                 bd_addr_copy(hci_stack->decline_addr, addr);
2669                 break;
2670             }
2671 
2672             if (hci_stack->gap_classic_accept_callback != NULL){
2673                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2674                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2675                     bd_addr_copy(hci_stack->decline_addr, addr);
2676                     break;
2677                 }
2678             }
2679 
2680             // TODO: eval COD 8-10
2681             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2682             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2683             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2684             if (!conn) {
2685                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2686             }
2687             if (!conn) {
2688                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2689                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2690                 bd_addr_copy(hci_stack->decline_addr, addr);
2691                 break;
2692             }
2693             conn->role  = HCI_ROLE_SLAVE;
2694             conn->state = RECEIVED_CONNECTION_REQUEST;
2695             // store info about eSCO
2696             if (link_type == HCI_LINK_TYPE_ESCO){
2697                 conn->remote_supported_features[0] |= 1;
2698             }
2699             hci_run();
2700             break;
2701 
2702         case HCI_EVENT_CONNECTION_COMPLETE:
2703             // Connection management
2704             reverse_bd_addr(&packet[5], addr);
2705             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2706             addr_type = BD_ADDR_TYPE_ACL;
2707             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2708             if (conn) {
2709                 if (!packet[2]){
2710                     conn->state = OPEN;
2711                     conn->con_handle = little_endian_read_16(packet, 3);
2712 
2713                     // queue set supervision timeout if we're master
2714                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2715                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2716                     }
2717 
2718                     // restart timer
2719                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2720                     btstack_run_loop_add_timer(&conn->timeout);
2721 
2722                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2723 
2724                     hci_emit_nr_connections_changed();
2725                 } else {
2726                     // connection failed
2727                     hci_handle_connection_failed(conn, packet[2]);
2728                 }
2729             }
2730             break;
2731 
2732         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2733             reverse_bd_addr(&packet[5], addr);
2734             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2735             if (packet[2]){
2736                 // connection failed
2737                 break;
2738             }
2739             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2740             if (!conn) {
2741                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2742             }
2743             if (!conn) {
2744                 break;
2745             }
2746             conn->state = OPEN;
2747             conn->con_handle = little_endian_read_16(packet, 3);
2748 
2749 #ifdef ENABLE_SCO_OVER_HCI
2750             // update SCO
2751             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2752                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2753             }
2754             // trigger can send now
2755             if (hci_have_usb_transport()){
2756                 hci_stack->sco_can_send_now = true;
2757             }
2758 #endif
2759 #ifdef HAVE_SCO_TRANSPORT
2760             // configure sco transport
2761             if (hci_stack->sco_transport != NULL){
2762                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2763                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2764             }
2765 #endif
2766             break;
2767 
2768         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2769             handle = little_endian_read_16(packet, 3);
2770             conn = hci_connection_for_handle(handle);
2771             if (!conn) break;
2772             if (!packet[2]){
2773                 const uint8_t * features = &packet[5];
2774                 hci_handle_remote_features_page_0(conn, features);
2775 
2776                 // read extended features if possible
2777                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2778                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2779                     break;
2780                 }
2781             }
2782             hci_handle_remote_features_received(conn);
2783             break;
2784 
2785         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2786             handle = little_endian_read_16(packet, 3);
2787             conn = hci_connection_for_handle(handle);
2788             if (!conn) break;
2789             // status = ok, page = 1
2790             if (!packet[2]) {
2791                 uint8_t page_number = packet[5];
2792                 uint8_t maximum_page_number = packet[6];
2793                 const uint8_t * features = &packet[7];
2794                 bool done = false;
2795                 switch (page_number){
2796                     case 1:
2797                         hci_handle_remote_features_page_1(conn, features);
2798                         if (maximum_page_number >= 2){
2799                             // get Secure Connections (Controller) from Page 2 if available
2800                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2801                         } else {
2802                             // otherwise, assume SC (Controller) == SC (Host)
2803                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2804                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2805                             }
2806                             done = true;
2807                         }
2808                         break;
2809                     case 2:
2810                         hci_handle_remote_features_page_2(conn, features);
2811                         done = true;
2812                         break;
2813                     default:
2814                         break;
2815                 }
2816                 if (!done) break;
2817             }
2818             hci_handle_remote_features_received(conn);
2819             break;
2820 
2821         case HCI_EVENT_LINK_KEY_REQUEST:
2822 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2823             hci_event_link_key_request_get_bd_addr(packet, addr);
2824             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2825             if (!conn) break;
2826 
2827             // lookup link key in db if not cached
2828             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2829                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2830             }
2831 
2832             // response sent by hci_run()
2833             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2834 #endif
2835             break;
2836 
2837         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2838             hci_event_link_key_request_get_bd_addr(packet, addr);
2839             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2840             if (!conn) break;
2841 
2842             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2843 
2844             // CVE-2020-26555: ignore NULL link key
2845             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2846             if (btstack_is_null(&packet[8], 16)) break;
2847 
2848             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2849             // Change Connection Encryption keeps link key type
2850             if (link_key_type != CHANGED_COMBINATION_KEY){
2851                 conn->link_key_type = link_key_type;
2852             }
2853 
2854             // cache link key. link keys stored in little-endian format for legacy reasons
2855             memcpy(&conn->link_key, &packet[8], 16);
2856 
2857             // only store link key:
2858             // - if bondable enabled
2859             if (hci_stack->bondable == false) break;
2860             // - if security level sufficient
2861             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2862             // - for SSP, also check if remote side requested bonding as well
2863             if (conn->link_key_type != COMBINATION_KEY){
2864                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2865                 if (!remote_bonding){
2866                     break;
2867                 }
2868             }
2869             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2870             break;
2871         }
2872 
2873         case HCI_EVENT_PIN_CODE_REQUEST:
2874             hci_event_pin_code_request_get_bd_addr(packet, addr);
2875             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2876             if (!conn) break;
2877 
2878             hci_pairing_started(conn, false);
2879             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2880             if (!hci_stack->bondable ){
2881                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2882                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2883                 hci_run();
2884                 return;
2885             }
2886             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2887             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2888                 log_info("Level 4 required, but SC not supported -> abort");
2889                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2890                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2891                 hci_run();
2892                 return;
2893             }
2894             break;
2895 
2896         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2897             hci_event_io_capability_response_get_bd_addr(packet, addr);
2898             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2899             if (!conn) break;
2900 
2901             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2902             hci_pairing_started(conn, true);
2903             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2904             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2905 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2906             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2907 #endif
2908             break;
2909 
2910         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2911             hci_event_io_capability_response_get_bd_addr(packet, addr);
2912             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2913             if (!conn) break;
2914 
2915             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2916             hci_connection_timestamp(conn);
2917             hci_pairing_started(conn, true);
2918             break;
2919 
2920 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2921         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2922             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2923             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2924             if (!conn) break;
2925 
2926             hci_connection_timestamp(conn);
2927 
2928             hci_pairing_started(conn, true);
2929 
2930             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2931             break;
2932 #endif
2933 
2934         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2935             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2936             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2937             if (!conn) break;
2938             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2939                 if (hci_stack->ssp_auto_accept){
2940                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2941                 };
2942             } else {
2943                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2944                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2945                 // don't forward event to app
2946                 hci_run();
2947                 return;
2948             }
2949             break;
2950 
2951         case HCI_EVENT_USER_PASSKEY_REQUEST:
2952             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2953             if (hci_stack->ssp_auto_accept){
2954                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2955             };
2956             break;
2957 
2958         case HCI_EVENT_MODE_CHANGE:
2959             handle = hci_event_mode_change_get_handle(packet);
2960             conn = hci_connection_for_handle(handle);
2961             if (!conn) break;
2962             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2963             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2964             break;
2965 #endif
2966 
2967         case HCI_EVENT_ENCRYPTION_CHANGE:
2968             handle = hci_event_encryption_change_get_connection_handle(packet);
2969             conn = hci_connection_for_handle(handle);
2970             if (!conn) break;
2971             if (hci_event_encryption_change_get_status(packet) == 0u) {
2972                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2973                 if (encryption_enabled){
2974                     if (hci_is_le_connection(conn)){
2975                         // For LE, we accept connection as encrypted
2976                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2977                     }
2978 #ifdef ENABLE_CLASSIC
2979                     else {
2980 
2981                         // dedicated bonding: send result and disconnect
2982                         if (conn->bonding_flags & BONDING_DEDICATED){
2983                             conn->bonding_flags &= ~BONDING_DEDICATED;
2984                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2985                             conn->bonding_status = packet[2];
2986                             break;
2987                         }
2988 
2989                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2990                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2991                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2992                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2993                             log_info("SC during pairing, but only E0 now -> abort");
2994                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2995                             break;
2996                         }
2997 
2998                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2999                         if (connected_uses_aes_ccm){
3000                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3001                         }
3002 
3003 #ifdef ENABLE_TESTING_SUPPORT
3004                         // work around for issue with PTS dongle
3005                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3006 #endif
3007 
3008                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3009                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3010                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3011                         } else {
3012                             // if not, pretend everything is perfect
3013                             hci_handle_read_encryption_key_size_complete(conn, 16);
3014                         }
3015                     }
3016 #endif
3017                 } else {
3018                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3019                 }
3020             }
3021 
3022             break;
3023 
3024 #ifdef ENABLE_CLASSIC
3025         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3026             handle = hci_event_authentication_complete_get_connection_handle(packet);
3027             conn = hci_connection_for_handle(handle);
3028             if (!conn) break;
3029 
3030             // clear authentication active flag
3031             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3032             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3033 
3034             // authenticated only if auth status == 0
3035             if (hci_event_authentication_complete_get_status(packet) == 0){
3036                 // authenticated
3037                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3038 
3039                 // If not already encrypted, start encryption
3040                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3041                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3042                     break;
3043                 }
3044             }
3045 
3046             // emit updated security level
3047             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3048             break;
3049 
3050         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3051             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3052             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3053             if (!conn) break;
3054 
3055             // treat successfully paired connection as authenticated
3056             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3057                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3058             }
3059 
3060             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3061             break;
3062 #endif
3063 
3064         // HCI_EVENT_DISCONNECTION_COMPLETE
3065         // has been split, to first notify stack before shutting connection down
3066         // see end of function, too.
3067         case HCI_EVENT_DISCONNECTION_COMPLETE:
3068             if (packet[2]) break;   // status != 0
3069             handle = little_endian_read_16(packet, 3);
3070             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3071             if (hci_stack->acl_fragmentation_total_size > 0u) {
3072                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3073                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3074                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3075                     hci_stack->acl_fragmentation_total_size = 0;
3076                     hci_stack->acl_fragmentation_pos = 0;
3077                     if (release_buffer){
3078                         hci_release_packet_buffer();
3079                     }
3080                 }
3081             }
3082 
3083             conn = hci_connection_for_handle(handle);
3084             if (!conn) break;
3085 #ifdef ENABLE_CLASSIC
3086             // pairing failed if it was ongoing
3087             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3088 #endif
3089 
3090             // emit dedicatd bonding event
3091             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3092                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3093             }
3094 
3095             // mark connection for shutdown, stop timers, reset state
3096             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3097             hci_connection_stop_timer(conn);
3098             hci_connection_init(conn);
3099 
3100 #ifdef ENABLE_BLE
3101 #ifdef ENABLE_LE_PERIPHERAL
3102             // re-enable advertisements for le connections if active
3103             if (hci_is_le_connection(conn)){
3104                 hci_update_advertisements_enabled_for_current_roles();
3105             }
3106 #endif
3107 #endif
3108             break;
3109 
3110         case HCI_EVENT_HARDWARE_ERROR:
3111             log_error("Hardware Error: 0x%02x", packet[2]);
3112             if (hci_stack->hardware_error_callback){
3113                 (*hci_stack->hardware_error_callback)(packet[2]);
3114             } else {
3115                 // if no special requests, just reboot stack
3116                 hci_power_control_off();
3117                 hci_power_control_on();
3118             }
3119             break;
3120 
3121 #ifdef ENABLE_CLASSIC
3122         case HCI_EVENT_ROLE_CHANGE:
3123             if (packet[2]) break;   // status != 0
3124             reverse_bd_addr(&packet[3], addr);
3125             addr_type = BD_ADDR_TYPE_ACL;
3126             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3127             if (!conn) break;
3128             conn->role = packet[9];
3129             break;
3130 #endif
3131 
3132         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3133             // release packet buffer only for asynchronous transport and if there are not further fragements
3134             if (hci_transport_synchronous()) {
3135                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3136                 return; // instead of break: to avoid re-entering hci_run()
3137             }
3138             hci_stack->acl_fragmentation_tx_active = 0;
3139             if (hci_stack->acl_fragmentation_total_size) break;
3140             hci_release_packet_buffer();
3141 
3142             // L2CAP receives this event via the hci_emit_event below
3143 
3144 #ifdef ENABLE_CLASSIC
3145             // For SCO, we do the can_send_now_check here
3146             hci_notify_if_sco_can_send_now();
3147 #endif
3148             break;
3149 
3150 #ifdef ENABLE_CLASSIC
3151         case HCI_EVENT_SCO_CAN_SEND_NOW:
3152             // For SCO, we do the can_send_now_check here
3153             hci_stack->sco_can_send_now = true;
3154             hci_notify_if_sco_can_send_now();
3155             return;
3156 
3157         // explode inquriy results for easier consumption
3158         case HCI_EVENT_INQUIRY_RESULT:
3159         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3160         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3161             gap_inquiry_explode(packet, size);
3162             break;
3163 #endif
3164 
3165 #ifdef ENABLE_BLE
3166         case HCI_EVENT_LE_META:
3167             switch (packet[2]){
3168 #ifdef ENABLE_LE_CENTRAL
3169                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3170                     // log_info("advertising report received");
3171                     if (!hci_stack->le_scanning_enabled) break;
3172                     le_handle_advertisement_report(packet, size);
3173                     break;
3174 #endif
3175                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3176 					event_handle_le_connection_complete(packet);
3177                     break;
3178 
3179                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3180                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3181                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3182                     conn = hci_connection_for_handle(handle);
3183                     if (!conn) break;
3184                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3185                     break;
3186 
3187                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3188                     // connection
3189                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3190                     conn = hci_connection_for_handle(handle);
3191                     if (conn) {
3192                         // read arguments
3193                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3194                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3195                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3196                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3197 
3198                         // validate against current connection parameter range
3199                         le_connection_parameter_range_t existing_range;
3200                         gap_get_connection_parameter_range(&existing_range);
3201                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3202                         if (update_parameter){
3203                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3204                             conn->le_conn_interval_min = le_conn_interval_min;
3205                             conn->le_conn_interval_max = le_conn_interval_max;
3206                             conn->le_conn_latency = le_conn_latency;
3207                             conn->le_supervision_timeout = le_supervision_timeout;
3208                         } else {
3209                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3210                         }
3211                     }
3212                     break;
3213 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3214                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3215                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3216                     conn = hci_connection_for_handle(handle);
3217                     if (conn) {
3218                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3219                     }
3220                     break;
3221 #endif
3222                 default:
3223                     break;
3224             }
3225             break;
3226 #endif
3227         case HCI_EVENT_VENDOR_SPECIFIC:
3228             // Vendor specific commands often create vendor specific event instead of num completed packets
3229             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3230             switch (hci_stack->manufacturer){
3231                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3232                     hci_stack->num_cmd_packets = 1;
3233                     break;
3234                 default:
3235                     break;
3236             }
3237             break;
3238         default:
3239             break;
3240     }
3241 
3242     handle_event_for_current_stack_state(packet, size);
3243 
3244     // notify upper stack
3245 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3246 
3247     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3248     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3249 		handle = little_endian_read_16(packet, 3);
3250 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3251 		// discard connection if app did not trigger a reconnect in the event handler
3252 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3253 			hci_shutdown_connection(aConn);
3254 		}
3255     }
3256 
3257 	// execute main loop
3258 	hci_run();
3259 }
3260 
3261 #ifdef ENABLE_CLASSIC
3262 
3263 #ifdef ENABLE_SCO_OVER_HCI
3264 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3265 static void sco_schedule_tx(hci_connection_t * conn);
3266 
3267 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3268     log_debug("SCO TX Timeout");
3269     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3270     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3271     if (!conn) return;
3272 
3273     // trigger send
3274     conn->sco_tx_ready = 1;
3275     // extra packet if CVSD but SCO buffer is too short
3276     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3277         conn->sco_tx_ready++;
3278     }
3279     hci_notify_if_sco_can_send_now();
3280 }
3281 
3282 
3283 #define SCO_TX_AFTER_RX_MS (6)
3284 
3285 static void sco_schedule_tx(hci_connection_t * conn){
3286 
3287     uint32_t now = btstack_run_loop_get_time_ms();
3288     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3289     int time_delta_ms = sco_tx_ms - now;
3290 
3291     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3292 
3293     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3294     btstack_run_loop_remove_timer(timer);
3295     btstack_run_loop_set_timer(timer, time_delta_ms);
3296     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3297     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3298     btstack_run_loop_add_timer(timer);
3299 }
3300 #endif
3301 
3302 static void sco_handler(uint8_t * packet, uint16_t size){
3303     // lookup connection struct
3304     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3305     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3306     if (!conn) return;
3307 
3308 #ifdef ENABLE_SCO_OVER_HCI
3309     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3310     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3311         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3312             packet[2] = 0x3c;
3313             memmove(&packet[3], &packet[23], 63);
3314             size = 63;
3315         }
3316     }
3317 
3318     if (hci_have_usb_transport()){
3319         // Nothing to do
3320     } else {
3321         // 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);
3322         if (hci_stack->synchronous_flow_control_enabled == 0){
3323             uint32_t now = btstack_run_loop_get_time_ms();
3324 
3325             if (!conn->sco_rx_valid){
3326                 // ignore first 10 packets
3327                 conn->sco_rx_count++;
3328                 // log_debug("sco rx count %u", conn->sco_rx_count);
3329                 if (conn->sco_rx_count == 10) {
3330                     // use first timestamp as is and pretent it just started
3331                     conn->sco_rx_ms = now;
3332                     conn->sco_rx_valid = 1;
3333                     conn->sco_rx_count = 0;
3334                     sco_schedule_tx(conn);
3335                 }
3336             } else {
3337                 // track expected arrival timme
3338                 conn->sco_rx_count++;
3339                 conn->sco_rx_ms += 7;
3340                 int delta = (int32_t) (now - conn->sco_rx_ms);
3341                 if (delta > 0){
3342                     conn->sco_rx_ms++;
3343                 }
3344                 // log_debug("sco rx %u", conn->sco_rx_ms);
3345                 sco_schedule_tx(conn);
3346             }
3347         }
3348     }
3349 #endif
3350 
3351     // deliver to app
3352     if (hci_stack->sco_packet_handler) {
3353         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3354     }
3355 
3356 #ifdef HAVE_SCO_TRANSPORT
3357     // We can send one packet for each received packet
3358     conn->sco_tx_ready++;
3359     hci_notify_if_sco_can_send_now();
3360 #endif
3361 
3362 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3363     conn->num_packets_completed++;
3364     hci_stack->host_completed_packets = 1;
3365     hci_run();
3366 #endif
3367 }
3368 #endif
3369 
3370 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3371     hci_dump_packet(packet_type, 1, packet, size);
3372     switch (packet_type) {
3373         case HCI_EVENT_PACKET:
3374             event_handler(packet, size);
3375             break;
3376         case HCI_ACL_DATA_PACKET:
3377             acl_handler(packet, size);
3378             break;
3379 #ifdef ENABLE_CLASSIC
3380         case HCI_SCO_DATA_PACKET:
3381             sco_handler(packet, size);
3382             break;
3383 #endif
3384         default:
3385             break;
3386     }
3387 }
3388 
3389 /**
3390  * @brief Add event packet handler.
3391  */
3392 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3393     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3394 }
3395 
3396 
3397 /** Register HCI packet handlers */
3398 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3399     hci_stack->acl_packet_handler = handler;
3400 }
3401 
3402 #ifdef ENABLE_CLASSIC
3403 /**
3404  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3405  */
3406 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3407     hci_stack->sco_packet_handler = handler;
3408 }
3409 #endif
3410 
3411 static void hci_state_reset(void){
3412     // no connections yet
3413     hci_stack->connections = NULL;
3414 
3415     // keep discoverable/connectable as this has been requested by the client(s)
3416     // hci_stack->discoverable = 0;
3417     // hci_stack->connectable = 0;
3418     // hci_stack->bondable = 1;
3419     // hci_stack->own_addr_type = 0;
3420 
3421     // buffer is free
3422     hci_stack->hci_packet_buffer_reserved = false;
3423 
3424     // no pending cmds
3425     hci_stack->decline_reason = 0;
3426 
3427     hci_stack->secure_connections_active = false;
3428 
3429 #ifdef ENABLE_CLASSIC
3430     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3431     hci_stack->gap_tasks =
3432             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3433             GAP_TASK_SET_CLASS_OF_DEVICE |
3434             GAP_TASK_SET_LOCAL_NAME |
3435             GAP_TASK_SET_EIR_DATA |
3436             GAP_TASK_WRITE_SCAN_ENABLE;
3437 #endif
3438 
3439 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3440     hci_stack->classic_read_local_oob_data = true;
3441     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3442 #endif
3443 
3444     // LE
3445 #ifdef ENABLE_BLE
3446     memset(hci_stack->le_random_address, 0, 6);
3447     hci_stack->le_random_address_set = 0;
3448 #endif
3449 #ifdef ENABLE_LE_CENTRAL
3450     hci_stack->le_scanning_active  = false;
3451     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3452     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3453     hci_stack->le_whitelist_capacity = 0;
3454 #endif
3455 #ifdef ENABLE_LE_PERIPHERAL
3456     hci_stack->le_advertisements_active = false;
3457     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3458         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3459     }
3460     if (hci_stack->le_advertisements_data != NULL){
3461         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3462     }
3463 #endif
3464 }
3465 
3466 #ifdef ENABLE_CLASSIC
3467 /**
3468  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3469  */
3470 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3471     // store and open remote device db
3472     hci_stack->link_key_db = link_key_db;
3473     if (hci_stack->link_key_db) {
3474         hci_stack->link_key_db->open();
3475     }
3476 }
3477 #endif
3478 
3479 void hci_init(const hci_transport_t *transport, const void *config){
3480 
3481 #ifdef HAVE_MALLOC
3482     if (!hci_stack) {
3483         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3484     }
3485 #else
3486     hci_stack = &hci_stack_static;
3487 #endif
3488     memset(hci_stack, 0, sizeof(hci_stack_t));
3489 
3490     // reference to use transport layer implementation
3491     hci_stack->hci_transport = transport;
3492 
3493     // reference to used config
3494     hci_stack->config = config;
3495 
3496     // setup pointer for outgoing packet buffer
3497     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3498 
3499     // max acl payload size defined in config.h
3500     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3501 
3502     // register packet handlers with transport
3503     transport->register_packet_handler(&packet_handler);
3504 
3505     hci_stack->state = HCI_STATE_OFF;
3506 
3507     // class of device
3508     hci_stack->class_of_device = 0x007a020c; // Smartphone
3509 
3510     // bondable by default
3511     hci_stack->bondable = 1;
3512 
3513 #ifdef ENABLE_CLASSIC
3514     // classic name
3515     hci_stack->local_name = default_classic_name;
3516 
3517     // Master slave policy
3518     hci_stack->master_slave_policy = 1;
3519 
3520     // Allow Role Switch
3521     hci_stack->allow_role_switch = 1;
3522 
3523     // Default / minimum security level = 2
3524     hci_stack->gap_security_level = LEVEL_2;
3525 
3526     // Default Security Mode 4
3527     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3528 
3529     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3530     hci_stack->gap_required_encyrption_key_size = 7;
3531 
3532     // Link Supervision Timeout
3533     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3534 
3535 #endif
3536 
3537     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3538     hci_stack->ssp_enable = 1;
3539     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3540     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3541     hci_stack->ssp_auto_accept = 1;
3542 
3543     // Secure Connections: enable (requires support from Controller)
3544     hci_stack->secure_connections_enable = true;
3545 
3546     // voice setting - signed 16 bit pcm data with CVSD over the air
3547     hci_stack->sco_voice_setting = 0x60;
3548 
3549 #ifdef ENABLE_LE_CENTRAL
3550     // connection parameter to use for outgoing connections
3551     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3552     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3553     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3554     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3555     hci_stack->le_connection_latency      = 4;         // 4
3556     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3557     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3558     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3559 
3560     // default LE Scanning
3561     hci_stack->le_scan_type     =   0x1; // active
3562     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3563     hci_stack->le_scan_window   =  0x30; //  30 ms
3564 #endif
3565 
3566 #ifdef ENABLE_LE_PERIPHERAL
3567     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3568 #endif
3569 
3570     // connection parameter range used to answer connection parameter update requests in l2cap
3571     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3572     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3573     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3574     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3575     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3576     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3577 
3578     hci_state_reset();
3579 }
3580 
3581 void hci_deinit(void){
3582 #ifdef HAVE_MALLOC
3583     if (hci_stack) {
3584         free(hci_stack);
3585     }
3586 #endif
3587     hci_stack = NULL;
3588 
3589 #ifdef ENABLE_CLASSIC
3590     disable_l2cap_timeouts = 0;
3591 #endif
3592 }
3593 
3594 /**
3595  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3596  */
3597 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3598     hci_stack->chipset = chipset_driver;
3599 
3600     // reset chipset driver - init is also called on power_up
3601     if (hci_stack->chipset && hci_stack->chipset->init){
3602         hci_stack->chipset->init(hci_stack->config);
3603     }
3604 }
3605 
3606 /**
3607  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3608  */
3609 void hci_set_control(const btstack_control_t *hardware_control){
3610     // references to used control implementation
3611     hci_stack->control = hardware_control;
3612     // init with transport config
3613     hardware_control->init(hci_stack->config);
3614 }
3615 
3616 void hci_close(void){
3617 
3618 #ifdef ENABLE_CLASSIC
3619     // close remote device db
3620     if (hci_stack->link_key_db) {
3621         hci_stack->link_key_db->close();
3622     }
3623 #endif
3624 
3625     btstack_linked_list_iterator_t lit;
3626     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3627     while (btstack_linked_list_iterator_has_next(&lit)){
3628         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3629         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3630         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3631         hci_shutdown_connection(connection);
3632     }
3633 
3634     hci_power_control(HCI_POWER_OFF);
3635 
3636 #ifdef HAVE_MALLOC
3637     free(hci_stack);
3638 #endif
3639     hci_stack = NULL;
3640 }
3641 
3642 #ifdef HAVE_SCO_TRANSPORT
3643 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3644     hci_stack->sco_transport = sco_transport;
3645     sco_transport->register_packet_handler(&packet_handler);
3646 }
3647 #endif
3648 
3649 #ifdef ENABLE_CLASSIC
3650 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3651     // validate ranage and set
3652     if (encryption_key_size < 7)  return;
3653     if (encryption_key_size > 16) return;
3654     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3655 }
3656 
3657 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3658     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3659         hci_stack->gap_security_mode = security_mode;
3660         return ERROR_CODE_SUCCESS;
3661     } else {
3662         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3663     }
3664 }
3665 
3666 gap_security_mode_t gap_get_security_mode(void){
3667     return hci_stack->gap_security_mode;
3668 }
3669 
3670 void gap_set_security_level(gap_security_level_t security_level){
3671     hci_stack->gap_security_level = security_level;
3672 }
3673 
3674 gap_security_level_t gap_get_security_level(void){
3675     if (hci_stack->gap_secure_connections_only_mode){
3676         return LEVEL_4;
3677     }
3678     return hci_stack->gap_security_level;
3679 }
3680 
3681 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3682     hci_stack->gap_minimal_service_security_level = security_level;
3683 }
3684 
3685 void gap_set_secure_connections_only_mode(bool enable){
3686     hci_stack->gap_secure_connections_only_mode = enable;
3687 }
3688 
3689 bool gap_get_secure_connections_only_mode(void){
3690     return hci_stack->gap_secure_connections_only_mode;
3691 }
3692 #endif
3693 
3694 #ifdef ENABLE_CLASSIC
3695 void gap_set_class_of_device(uint32_t class_of_device){
3696     hci_stack->class_of_device = class_of_device;
3697     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3698     hci_run();
3699 }
3700 
3701 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3702     hci_stack->default_link_policy_settings = default_link_policy_settings;
3703     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3704     hci_run();
3705 }
3706 
3707 void gap_set_allow_role_switch(bool allow_role_switch){
3708     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3709 }
3710 
3711 uint8_t hci_get_allow_role_switch(void){
3712     return  hci_stack->allow_role_switch;
3713 }
3714 
3715 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3716     hci_stack->link_supervision_timeout = link_supervision_timeout;
3717 }
3718 
3719 void hci_disable_l2cap_timeout_check(void){
3720     disable_l2cap_timeouts = 1;
3721 }
3722 #endif
3723 
3724 #ifndef HAVE_HOST_CONTROLLER_API
3725 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3726 void hci_set_bd_addr(bd_addr_t addr){
3727     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3728     hci_stack->custom_bd_addr_set = 1;
3729 }
3730 #endif
3731 
3732 // State-Module-Driver overview
3733 // state                    module  low-level
3734 // HCI_STATE_OFF             off      close
3735 // HCI_STATE_INITIALIZING,   on       open
3736 // HCI_STATE_WORKING,        on       open
3737 // HCI_STATE_HALTING,        on       open
3738 // HCI_STATE_SLEEPING,    off/sleep   close
3739 // HCI_STATE_FALLING_ASLEEP  on       open
3740 
3741 static int hci_power_control_on(void){
3742 
3743     // power on
3744     int err = 0;
3745     if (hci_stack->control && hci_stack->control->on){
3746         err = (*hci_stack->control->on)();
3747     }
3748     if (err){
3749         log_error( "POWER_ON failed");
3750         hci_emit_hci_open_failed();
3751         return err;
3752     }
3753 
3754     // int chipset driver
3755     if (hci_stack->chipset && hci_stack->chipset->init){
3756         hci_stack->chipset->init(hci_stack->config);
3757     }
3758 
3759     // init transport
3760     if (hci_stack->hci_transport->init){
3761         hci_stack->hci_transport->init(hci_stack->config);
3762     }
3763 
3764     // open transport
3765     err = hci_stack->hci_transport->open();
3766     if (err){
3767         log_error( "HCI_INIT failed, turning Bluetooth off again");
3768         if (hci_stack->control && hci_stack->control->off){
3769             (*hci_stack->control->off)();
3770         }
3771         hci_emit_hci_open_failed();
3772         return err;
3773     }
3774     return 0;
3775 }
3776 
3777 static void hci_power_control_off(void){
3778 
3779     log_info("hci_power_control_off");
3780 
3781     // close low-level device
3782     hci_stack->hci_transport->close();
3783 
3784     log_info("hci_power_control_off - hci_transport closed");
3785 
3786     // power off
3787     if (hci_stack->control && hci_stack->control->off){
3788         (*hci_stack->control->off)();
3789     }
3790 
3791     log_info("hci_power_control_off - control closed");
3792 
3793     hci_stack->state = HCI_STATE_OFF;
3794 }
3795 
3796 static void hci_power_control_sleep(void){
3797 
3798     log_info("hci_power_control_sleep");
3799 
3800 #if 0
3801     // don't close serial port during sleep
3802 
3803     // close low-level device
3804     hci_stack->hci_transport->close(hci_stack->config);
3805 #endif
3806 
3807     // sleep mode
3808     if (hci_stack->control && hci_stack->control->sleep){
3809         (*hci_stack->control->sleep)();
3810     }
3811 
3812     hci_stack->state = HCI_STATE_SLEEPING;
3813 }
3814 
3815 static int hci_power_control_wake(void){
3816 
3817     log_info("hci_power_control_wake");
3818 
3819     // wake on
3820     if (hci_stack->control && hci_stack->control->wake){
3821         (*hci_stack->control->wake)();
3822     }
3823 
3824 #if 0
3825     // open low-level device
3826     int err = hci_stack->hci_transport->open(hci_stack->config);
3827     if (err){
3828         log_error( "HCI_INIT failed, turning Bluetooth off again");
3829         if (hci_stack->control && hci_stack->control->off){
3830             (*hci_stack->control->off)();
3831         }
3832         hci_emit_hci_open_failed();
3833         return err;
3834     }
3835 #endif
3836 
3837     return 0;
3838 }
3839 
3840 static void hci_power_transition_to_initializing(void){
3841     // set up state machine
3842     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3843     hci_stack->hci_packet_buffer_reserved = false;
3844     hci_stack->state = HCI_STATE_INITIALIZING;
3845     hci_stack->substate = HCI_INIT_SEND_RESET;
3846 }
3847 
3848 // returns error
3849 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3850     int err;
3851     switch (power_mode){
3852         case HCI_POWER_ON:
3853             err = hci_power_control_on();
3854             if (err != 0) {
3855                 log_error("hci_power_control_on() error %d", err);
3856                 return err;
3857             }
3858             hci_power_transition_to_initializing();
3859             break;
3860         case HCI_POWER_OFF:
3861             // do nothing
3862             break;
3863         case HCI_POWER_SLEEP:
3864             // do nothing (with SLEEP == OFF)
3865             break;
3866         default:
3867             btstack_assert(false);
3868             break;
3869     }
3870     return ERROR_CODE_SUCCESS;
3871 }
3872 
3873 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3874     switch (power_mode){
3875         case HCI_POWER_ON:
3876             // do nothing
3877             break;
3878         case HCI_POWER_OFF:
3879             // no connections yet, just turn it off
3880             hci_power_control_off();
3881             break;
3882         case HCI_POWER_SLEEP:
3883             // no connections yet, just turn it off
3884             hci_power_control_sleep();
3885             break;
3886         default:
3887             btstack_assert(false);
3888             break;
3889     }
3890     return ERROR_CODE_SUCCESS;
3891 }
3892 
3893 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3894     switch (power_mode){
3895         case HCI_POWER_ON:
3896             // do nothing
3897             break;
3898         case HCI_POWER_OFF:
3899             // see hci_run
3900             hci_stack->state = HCI_STATE_HALTING;
3901             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3902             break;
3903         case HCI_POWER_SLEEP:
3904             // see hci_run
3905             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3906             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3907             break;
3908         default:
3909             btstack_assert(false);
3910             break;
3911     }
3912     return ERROR_CODE_SUCCESS;
3913 }
3914 
3915 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3916     switch (power_mode){
3917         case HCI_POWER_ON:
3918             hci_power_transition_to_initializing();
3919             break;
3920         case HCI_POWER_OFF:
3921             // do nothing
3922             break;
3923         case HCI_POWER_SLEEP:
3924             // see hci_run
3925             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3926             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3927             break;
3928         default:
3929             btstack_assert(false);
3930             break;
3931     }
3932     return ERROR_CODE_SUCCESS;
3933 }
3934 
3935 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3936     switch (power_mode){
3937         case HCI_POWER_ON:
3938             hci_power_transition_to_initializing();
3939             break;
3940         case HCI_POWER_OFF:
3941             // see hci_run
3942             hci_stack->state = HCI_STATE_HALTING;
3943             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3944             break;
3945         case HCI_POWER_SLEEP:
3946             // do nothing
3947             break;
3948         default:
3949             btstack_assert(false);
3950             break;
3951     }
3952     return ERROR_CODE_SUCCESS;
3953 }
3954 
3955 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3956     int err;
3957     switch (power_mode){
3958         case HCI_POWER_ON:
3959             err = hci_power_control_wake();
3960             if (err) return err;
3961             hci_power_transition_to_initializing();
3962             break;
3963         case HCI_POWER_OFF:
3964             hci_stack->state = HCI_STATE_HALTING;
3965             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3966             break;
3967         case HCI_POWER_SLEEP:
3968             // do nothing
3969             break;
3970         default:
3971             btstack_assert(false);
3972             break;
3973     }
3974     return ERROR_CODE_SUCCESS;
3975 }
3976 
3977 int hci_power_control(HCI_POWER_MODE power_mode){
3978     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3979     int err = 0;
3980     switch (hci_stack->state){
3981         case HCI_STATE_OFF:
3982             err = hci_power_control_state_off(power_mode);
3983             break;
3984         case HCI_STATE_INITIALIZING:
3985             err = hci_power_control_state_initializing(power_mode);
3986             break;
3987         case HCI_STATE_WORKING:
3988             err = hci_power_control_state_working(power_mode);
3989             break;
3990         case HCI_STATE_HALTING:
3991             err = hci_power_control_state_halting(power_mode);
3992             break;
3993         case HCI_STATE_FALLING_ASLEEP:
3994             err = hci_power_control_state_falling_asleep(power_mode);
3995             break;
3996         case HCI_STATE_SLEEPING:
3997             err = hci_power_control_state_sleeping(power_mode);
3998             break;
3999         default:
4000             btstack_assert(false);
4001             break;
4002     }
4003     if (err != 0){
4004         return err;
4005     }
4006 
4007     // create internal event
4008 	hci_emit_state();
4009 
4010 	// trigger next/first action
4011 	hci_run();
4012 
4013     return 0;
4014 }
4015 
4016 
4017 #ifdef ENABLE_CLASSIC
4018 
4019 static void hci_update_scan_enable(void){
4020     // 2 = page scan, 1 = inq scan
4021     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4022     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4023     hci_run();
4024 }
4025 
4026 void gap_discoverable_control(uint8_t enable){
4027     if (enable) enable = 1; // normalize argument
4028 
4029     if (hci_stack->discoverable == enable){
4030         hci_emit_discoverable_enabled(hci_stack->discoverable);
4031         return;
4032     }
4033 
4034     hci_stack->discoverable = enable;
4035     hci_update_scan_enable();
4036 }
4037 
4038 void gap_connectable_control(uint8_t enable){
4039     if (enable) enable = 1; // normalize argument
4040 
4041     // don't emit event
4042     if (hci_stack->connectable == enable) return;
4043 
4044     hci_stack->connectable = enable;
4045     hci_update_scan_enable();
4046 }
4047 #endif
4048 
4049 void gap_local_bd_addr(bd_addr_t address_buffer){
4050     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4051 }
4052 
4053 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4054 static void hci_host_num_completed_packets(void){
4055 
4056     // create packet manually as arrays are not supported and num_commands should not get reduced
4057     hci_reserve_packet_buffer();
4058     uint8_t * packet = hci_get_outgoing_packet_buffer();
4059 
4060     uint16_t size = 0;
4061     uint16_t num_handles = 0;
4062     packet[size++] = 0x35;
4063     packet[size++] = 0x0c;
4064     size++;  // skip param len
4065     size++;  // skip num handles
4066 
4067     // add { handle, packets } entries
4068     btstack_linked_item_t * it;
4069     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4070         hci_connection_t * connection = (hci_connection_t *) it;
4071         if (connection->num_packets_completed){
4072             little_endian_store_16(packet, size, connection->con_handle);
4073             size += 2;
4074             little_endian_store_16(packet, size, connection->num_packets_completed);
4075             size += 2;
4076             //
4077             num_handles++;
4078             connection->num_packets_completed = 0;
4079         }
4080     }
4081 
4082     packet[2] = size - 3;
4083     packet[3] = num_handles;
4084 
4085     hci_stack->host_completed_packets = 0;
4086 
4087     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4088     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4089 
4090     // release packet buffer for synchronous transport implementations
4091     if (hci_transport_synchronous()){
4092         hci_release_packet_buffer();
4093         hci_emit_transport_packet_sent();
4094     }
4095 }
4096 #endif
4097 
4098 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4099     UNUSED(ds);
4100     hci_stack->substate = HCI_HALTING_CLOSE;
4101     // allow packet handlers to defer final shutdown
4102     hci_emit_state();
4103     hci_run();
4104 }
4105 
4106 static bool hci_run_acl_fragments(void){
4107     if (hci_stack->acl_fragmentation_total_size > 0u) {
4108         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4109         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4110         if (connection) {
4111             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4112                 hci_send_acl_packet_fragments(connection);
4113                 return true;
4114             }
4115         } else {
4116             // connection gone -> discard further fragments
4117             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4118             hci_stack->acl_fragmentation_total_size = 0;
4119             hci_stack->acl_fragmentation_pos = 0;
4120         }
4121     }
4122     return false;
4123 }
4124 
4125 #ifdef ENABLE_CLASSIC
4126 static bool hci_run_general_gap_classic(void){
4127 
4128     // assert stack is working and classic is active
4129     if (hci_classic_supported() == false)      return false;
4130     if (hci_stack->state != HCI_STATE_WORKING) return false;
4131 
4132     // decline incoming connections
4133     if (hci_stack->decline_reason){
4134         uint8_t reason = hci_stack->decline_reason;
4135         hci_stack->decline_reason = 0;
4136         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4137         return true;
4138     }
4139 
4140     if (hci_stack->gap_tasks != 0){
4141         hci_run_gap_tasks_classic();
4142         return true;
4143     }
4144 
4145     // start/stop inquiry
4146     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4147         uint8_t duration = hci_stack->inquiry_state;
4148         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4149         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4150         return true;
4151     }
4152     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4153         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4154         hci_send_cmd(&hci_inquiry_cancel);
4155         return true;
4156     }
4157     // remote name request
4158     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4159         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4160         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4161                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4162         return true;
4163     }
4164 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4165     // Local OOB data
4166     if (hci_stack->classic_read_local_oob_data){
4167         hci_stack->classic_read_local_oob_data = false;
4168         if (hci_stack->local_supported_commands[1] & 0x10u){
4169             hci_send_cmd(&hci_read_local_extended_oob_data);
4170         } else {
4171             hci_send_cmd(&hci_read_local_oob_data);
4172         }
4173     }
4174 #endif
4175     // pairing
4176     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4177         uint8_t state = hci_stack->gap_pairing_state;
4178         uint8_t pin_code[16];
4179         switch (state){
4180             case GAP_PAIRING_STATE_SEND_PIN:
4181                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4182                 memset(pin_code, 0, 16);
4183                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4184                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4185                 break;
4186             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4187                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4188                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4189                 break;
4190             case GAP_PAIRING_STATE_SEND_PASSKEY:
4191                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4192                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4193                 break;
4194             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4195                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4196                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4197                 break;
4198             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4199                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4200                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4201                 break;
4202             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4203                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4204                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4205                 break;
4206             default:
4207                 break;
4208         }
4209         return true;
4210     }
4211     return false;
4212 }
4213 #endif
4214 
4215 #ifdef ENABLE_BLE
4216 static bool hci_run_general_gap_le(void){
4217 
4218     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4219 
4220     if (hci_stack->state != HCI_STATE_WORKING) return false;
4221     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4222 
4223 
4224     // Phase 1: collect what to stop
4225 
4226     bool scanning_stop = false;
4227     bool connecting_stop = false;
4228     bool advertising_stop = false;
4229 
4230 #ifndef ENABLE_LE_CENTRAL
4231     UNUSED(scanning_stop);
4232     UNUSED(connecting_stop);
4233 #endif
4234 #ifndef ENABLE_LE_PERIPHERAL
4235     UNUSED(advertising_stop);
4236 #endif
4237 
4238     // check if whitelist needs modification
4239     bool whitelist_modification_pending = false;
4240     btstack_linked_list_iterator_t lit;
4241     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4242     while (btstack_linked_list_iterator_has_next(&lit)){
4243         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4244         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4245             whitelist_modification_pending = true;
4246             break;
4247         }
4248     }
4249     // check if resolving list needs modification
4250     bool resolving_list_modification_pending = false;
4251 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4252     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4253 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4254         resolving_list_modification_pending = true;
4255     }
4256 #endif
4257 
4258 #ifdef ENABLE_LE_CENTRAL
4259     // scanning control
4260     if (hci_stack->le_scanning_active) {
4261         // stop if:
4262         // - parameter change required
4263         // - it's disabled
4264         // - whitelist change required but used for scanning
4265         // - resolving list modified
4266         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4267         if ((hci_stack->le_scanning_param_update) ||
4268             !hci_stack->le_scanning_enabled ||
4269             scanning_uses_whitelist ||
4270             resolving_list_modification_pending){
4271 
4272             scanning_stop = true;
4273         }
4274     }
4275 #endif
4276 
4277 #ifdef ENABLE_LE_CENTRAL
4278     // connecting control
4279     bool connecting_with_whitelist;
4280     switch (hci_stack->le_connecting_state){
4281         case LE_CONNECTING_DIRECT:
4282         case LE_CONNECTING_WHITELIST:
4283             // stop connecting if:
4284             // - connecting uses white and whitelist modification pending
4285             // - if it got disabled
4286             // - resolving list modified
4287             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4288             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4289                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4290                 resolving_list_modification_pending) {
4291 
4292                 connecting_stop = true;
4293             }
4294             break;
4295         default:
4296             break;
4297     }
4298 #endif
4299 
4300 #ifdef ENABLE_LE_PERIPHERAL
4301     // le advertisement control
4302     if (hci_stack->le_advertisements_active){
4303         // stop if:
4304         // - parameter change required
4305         // - it's disabled
4306         // - whitelist change required but used for advertisement filter policy
4307         // - resolving list modified
4308         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4309         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4310         if (advertising_change ||
4311             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4312             (advertising_uses_whitelist & whitelist_modification_pending) ||
4313             resolving_list_modification_pending) {
4314 
4315             advertising_stop = true;
4316         }
4317     }
4318 #endif
4319 
4320 
4321     // Phase 2: stop everything that should be off during modifications
4322 
4323 #ifdef ENABLE_LE_CENTRAL
4324     if (scanning_stop){
4325         hci_stack->le_scanning_active = false;
4326         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4327         return true;
4328     }
4329 #endif
4330 
4331 #ifdef ENABLE_LE_CENTRAL
4332     if (connecting_stop){
4333         hci_send_cmd(&hci_le_create_connection_cancel);
4334         return true;
4335     }
4336 #endif
4337 
4338 #ifdef ENABLE_LE_PERIPHERAL
4339     if (advertising_stop){
4340         hci_stack->le_advertisements_active = false;
4341         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4342         return true;
4343     }
4344 #endif
4345 
4346     // Phase 3: modify
4347 
4348 #ifdef ENABLE_LE_CENTRAL
4349     if (hci_stack->le_scanning_param_update){
4350         hci_stack->le_scanning_param_update = false;
4351         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4352                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4353         return true;
4354     }
4355 #endif
4356 
4357 #ifdef ENABLE_LE_PERIPHERAL
4358     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4359         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4360         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4361         hci_send_cmd(&hci_le_set_advertising_parameters,
4362                      hci_stack->le_advertisements_interval_min,
4363                      hci_stack->le_advertisements_interval_max,
4364                      hci_stack->le_advertisements_type,
4365                      hci_stack->le_advertisements_own_addr_type,
4366                      hci_stack->le_advertisements_direct_address_type,
4367                      hci_stack->le_advertisements_direct_address,
4368                      hci_stack->le_advertisements_channel_map,
4369                      hci_stack->le_advertisements_filter_policy);
4370         return true;
4371     }
4372     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4373         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4374         uint8_t adv_data_clean[31];
4375         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4376         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4377                      hci_stack->le_advertisements_data_len);
4378         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4379         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4380         return true;
4381     }
4382     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4383         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4384         uint8_t scan_data_clean[31];
4385         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4386         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4387                      hci_stack->le_scan_response_data_len);
4388         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4389         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4390         return true;
4391     }
4392 #endif
4393 
4394 
4395 #ifdef ENABLE_LE_CENTRAL
4396     // if connect with whitelist was active and is not cancelled yet, wait until next time
4397     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4398 #endif
4399 
4400     // LE Whitelist Management
4401     if (whitelist_modification_pending){
4402         // add/remove entries
4403         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4404         while (btstack_linked_list_iterator_has_next(&lit)){
4405             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4406 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4407 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4408 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4409 				return true;
4410 			}
4411             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4412 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4413                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4414                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4415                 return true;
4416             }
4417             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4418 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4419 				btstack_memory_whitelist_entry_free(entry);
4420             }
4421         }
4422     }
4423 
4424 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4425     // LE Resolving List Management
4426     if (resolving_list_supported) {
4427 		uint16_t i;
4428 		switch (hci_stack->le_resolving_list_state) {
4429 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4430 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4431 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4432 				return true;
4433 			case LE_RESOLVING_LIST_READ_SIZE:
4434 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4435 				hci_send_cmd(&hci_le_read_resolving_list_size);
4436 				return true;
4437 			case LE_RESOLVING_LIST_SEND_CLEAR:
4438 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4439 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4440 							  sizeof(hci_stack->le_resolving_list_add_entries));
4441 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4442 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4443 				hci_send_cmd(&hci_le_clear_resolving_list);
4444 				return true;
4445 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4446 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4447 					uint8_t offset = i >> 3;
4448 					uint8_t mask = 1 << (i & 7);
4449 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4450 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4451 					bd_addr_t peer_identity_addreses;
4452 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4453 					sm_key_t peer_irk;
4454 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4455 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4456 
4457 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4458 					// trigger whitelist entry 'update' (work around for controller bug)
4459 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4460 					while (btstack_linked_list_iterator_has_next(&lit)) {
4461 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4462 						if (entry->address_type != peer_identity_addr_type) continue;
4463 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4464 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4465 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4466 					}
4467 #endif
4468 
4469 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4470 								 peer_identity_addreses);
4471 					return true;
4472 				}
4473 
4474 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4475 
4476 				/* fall through */
4477 
4478 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4479 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4480 					uint8_t offset = i >> 3;
4481 					uint8_t mask = 1 << (i & 7);
4482 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4483 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4484 					bd_addr_t peer_identity_addreses;
4485 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4486 					sm_key_t peer_irk;
4487 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4488 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4489 					const uint8_t *local_irk = gap_get_persistent_irk();
4490 					// command uses format specifier 'P' that stores 16-byte value without flip
4491 					uint8_t local_irk_flipped[16];
4492 					uint8_t peer_irk_flipped[16];
4493 					reverse_128(local_irk, local_irk_flipped);
4494 					reverse_128(peer_irk, peer_irk_flipped);
4495 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4496 								 peer_irk_flipped, local_irk_flipped);
4497 					return true;
4498 				}
4499 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4500 				break;
4501 
4502 			default:
4503 				break;
4504 		}
4505 	}
4506     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4507 #endif
4508 
4509     // Phase 4: restore state
4510 
4511 #ifdef ENABLE_LE_CENTRAL
4512     // re-start scanning
4513     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4514         hci_stack->le_scanning_active = true;
4515         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4516         return true;
4517     }
4518 #endif
4519 
4520 #ifdef ENABLE_LE_CENTRAL
4521     // re-start connecting
4522     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4523         bd_addr_t null_addr;
4524         memset(null_addr, 0, 6);
4525         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4526         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4527         hci_send_cmd(&hci_le_create_connection,
4528                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4529                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4530                      1,         // use whitelist
4531                      0,         // peer address type
4532                      null_addr, // peer bd addr
4533                      hci_stack->le_connection_own_addr_type,   // our addr type:
4534                      hci_stack->le_connection_interval_min,    // conn interval min
4535                      hci_stack->le_connection_interval_max,    // conn interval max
4536                      hci_stack->le_connection_latency,         // conn latency
4537                      hci_stack->le_supervision_timeout,        // conn latency
4538                      hci_stack->le_minimum_ce_length,          // min ce length
4539                      hci_stack->le_maximum_ce_length           // max ce length
4540         );
4541         return true;
4542     }
4543 #endif
4544 
4545 #ifdef ENABLE_LE_PERIPHERAL
4546     // re-start advertising
4547     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4548         // check if advertisements should be enabled given
4549         hci_stack->le_advertisements_active = true;
4550         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4551         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4552         return true;
4553     }
4554 #endif
4555 
4556     return false;
4557 }
4558 #endif
4559 
4560 static bool hci_run_general_pending_commands(void){
4561     btstack_linked_item_t * it;
4562     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4563         hci_connection_t * connection = (hci_connection_t *) it;
4564 
4565         switch(connection->state){
4566             case SEND_CREATE_CONNECTION:
4567                 switch(connection->address_type){
4568 #ifdef ENABLE_CLASSIC
4569                     case BD_ADDR_TYPE_ACL:
4570                         log_info("sending hci_create_connection");
4571                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4572                         break;
4573 #endif
4574                     default:
4575 #ifdef ENABLE_BLE
4576 #ifdef ENABLE_LE_CENTRAL
4577                         log_info("sending hci_le_create_connection");
4578                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4579                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4580                         hci_send_cmd(&hci_le_create_connection,
4581                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4582                                      hci_stack->le_connection_scan_window,      // conn scan windows
4583                                      0,         // don't use whitelist
4584                                      connection->address_type, // peer address type
4585                                      connection->address,      // peer bd addr
4586                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4587                                      hci_stack->le_connection_interval_min,    // conn interval min
4588                                      hci_stack->le_connection_interval_max,    // conn interval max
4589                                      hci_stack->le_connection_latency,         // conn latency
4590                                      hci_stack->le_supervision_timeout,        // conn latency
4591                                      hci_stack->le_minimum_ce_length,          // min ce length
4592                                      hci_stack->le_maximum_ce_length          // max ce length
4593                         );
4594                         connection->state = SENT_CREATE_CONNECTION;
4595 #endif
4596 #endif
4597                         break;
4598                 }
4599                 return true;
4600 
4601 #ifdef ENABLE_CLASSIC
4602             case RECEIVED_CONNECTION_REQUEST:
4603                 connection->role  = HCI_ROLE_SLAVE;
4604                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4605                     log_info("sending hci_accept_connection_request");
4606                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4607                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4608                 }
4609                 return true;
4610 #endif
4611 
4612 #ifdef ENABLE_BLE
4613 #ifdef ENABLE_LE_CENTRAL
4614             case SEND_CANCEL_CONNECTION:
4615                 connection->state = SENT_CANCEL_CONNECTION;
4616                 hci_send_cmd(&hci_le_create_connection_cancel);
4617                 return true;
4618 #endif
4619 #endif
4620             case SEND_DISCONNECT:
4621                 connection->state = SENT_DISCONNECT;
4622                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4623                 return true;
4624 
4625             default:
4626                 break;
4627         }
4628 
4629         // no further commands if connection is about to get shut down
4630         if (connection->state == SENT_DISCONNECT) continue;
4631 
4632         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4633             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4634             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4635             return true;
4636         }
4637 
4638 #ifdef ENABLE_CLASSIC
4639 
4640         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4641             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4642             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4643             return true;
4644         }
4645 
4646         // Handling link key request requires remote supported features
4647         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4648             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4649             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4650 
4651             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4652             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4653             if (have_link_key && security_level_sufficient){
4654                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4655             } else {
4656                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4657             }
4658             return true;
4659         }
4660 
4661         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4662             log_info("denying to pin request");
4663             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4664             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4665             return true;
4666         }
4667 
4668         // security assessment requires remote features
4669         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4670             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4671             hci_ssp_assess_security_on_io_cap_request(connection);
4672             // 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
4673         }
4674 
4675         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4676             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4677             // set authentication requirements:
4678             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4679             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4680             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4681             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4682                 authreq |= 1;
4683             }
4684             bool bonding = hci_stack->bondable;
4685             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4686                 // if we have received IO Cap Response, we're in responder role
4687                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4688                 if (bonding && !remote_bonding){
4689                     log_info("Remote not bonding, dropping local flag");
4690                     bonding = false;
4691                 }
4692             }
4693             if (bonding){
4694                 if (connection->bonding_flags & BONDING_DEDICATED){
4695                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4696                 } else {
4697                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4698                 }
4699             }
4700             uint8_t have_oob_data = 0;
4701 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4702             if (connection->classic_oob_c_192 != NULL){
4703                     have_oob_data |= 1;
4704             }
4705             if (connection->classic_oob_c_256 != NULL){
4706                 have_oob_data |= 2;
4707             }
4708 #endif
4709             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4710             return true;
4711         }
4712 
4713         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4714             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4715             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4716             return true;
4717         }
4718 
4719 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4720         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4721             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4722             const uint8_t zero[16] = { 0 };
4723             const uint8_t * r_192 = zero;
4724             const uint8_t * c_192 = zero;
4725             const uint8_t * r_256 = zero;
4726             const uint8_t * c_256 = zero;
4727             // verify P-256 OOB
4728             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4729                 c_256 = connection->classic_oob_c_256;
4730                 if (connection->classic_oob_r_256 != NULL) {
4731                     r_256 = connection->classic_oob_r_256;
4732                 }
4733             }
4734             // verify P-192 OOB
4735             if ((connection->classic_oob_c_192 != NULL)) {
4736                 c_192 = connection->classic_oob_c_192;
4737                 if (connection->classic_oob_r_192 != NULL) {
4738                     r_192 = connection->classic_oob_r_192;
4739                 }
4740             }
4741 
4742             // assess security
4743             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4744             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4745             if (need_level_4 && !can_reach_level_4){
4746                 log_info("Level 4 required, but not possible -> abort");
4747                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4748                 // send oob negative reply
4749                 c_256 = NULL;
4750                 c_192 = NULL;
4751             }
4752 
4753             // Reply
4754             if (c_256 != zero) {
4755                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4756             } else if (c_192 != zero){
4757                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4758             } else {
4759                 hci_stack->classic_oob_con_handle = connection->con_handle;
4760                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4761             }
4762             return true;
4763         }
4764 #endif
4765 
4766         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4767             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4768             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4769             return true;
4770         }
4771 
4772         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4773             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4774             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4775             return true;
4776         }
4777 
4778         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4779             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4780             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4781             return true;
4782         }
4783 
4784         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4785             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4786             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4787             connection->state = SENT_DISCONNECT;
4788             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4789             return true;
4790         }
4791 
4792         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4793             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4794             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4795             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4796             return true;
4797         }
4798 
4799         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4800             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4801             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4802             return true;
4803         }
4804 
4805         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4806             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4807             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4808             return true;
4809         }
4810 
4811         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4812             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4813             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4814             return true;
4815         }
4816 
4817         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4818             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4819             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4820             return true;
4821         }
4822 
4823         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4824             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4825             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4826             return true;
4827         }
4828 #endif
4829 
4830         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4831             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4832 #ifdef ENABLE_CLASSIC
4833             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4834 #endif
4835             if (connection->state != SENT_DISCONNECT){
4836                 connection->state = SENT_DISCONNECT;
4837                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4838                 return true;
4839             }
4840         }
4841 
4842 #ifdef ENABLE_CLASSIC
4843         uint16_t sniff_min_interval;
4844         switch (connection->sniff_min_interval){
4845             case 0:
4846                 break;
4847             case 0xffff:
4848                 connection->sniff_min_interval = 0;
4849                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4850                 return true;
4851             default:
4852                 sniff_min_interval = connection->sniff_min_interval;
4853                 connection->sniff_min_interval = 0;
4854                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4855                 return true;
4856         }
4857 
4858         if (connection->sniff_subrating_max_latency != 0xffff){
4859             uint16_t max_latency = connection->sniff_subrating_max_latency;
4860             connection->sniff_subrating_max_latency = 0;
4861             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4862             return true;
4863         }
4864 
4865         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4866             uint8_t service_type = (uint8_t) connection->qos_service_type;
4867             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4868             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);
4869             return true;
4870         }
4871 
4872         if (connection->request_role != HCI_ROLE_INVALID){
4873             hci_role_t role = connection->request_role;
4874             connection->request_role = HCI_ROLE_INVALID;
4875             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4876             return true;
4877         }
4878 #endif
4879 
4880 #ifdef ENABLE_BLE
4881         switch (connection->le_con_parameter_update_state){
4882             // response to L2CAP CON PARAMETER UPDATE REQUEST
4883             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4884                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4885                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4886                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4887                              0x0000, 0xffff);
4888                 return true;
4889             case CON_PARAMETER_UPDATE_REPLY:
4890                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4891                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4892                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4893                              0x0000, 0xffff);
4894                 return true;
4895             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4896                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4897                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4898                 return true;
4899             default:
4900                 break;
4901         }
4902         if (connection->le_phy_update_all_phys != 0xffu){
4903             uint8_t all_phys = connection->le_phy_update_all_phys;
4904             connection->le_phy_update_all_phys = 0xff;
4905             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);
4906             return true;
4907         }
4908 #endif
4909     }
4910     return false;
4911 }
4912 
4913 static void hci_run(void){
4914 
4915     bool done;
4916 
4917     // send continuation fragments first, as they block the prepared packet buffer
4918     done = hci_run_acl_fragments();
4919     if (done) return;
4920 
4921 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4922     // send host num completed packets next as they don't require num_cmd_packets > 0
4923     if (!hci_can_send_comand_packet_transport()) return;
4924     if (hci_stack->host_completed_packets){
4925         hci_host_num_completed_packets();
4926         return;
4927     }
4928 #endif
4929 
4930     if (!hci_can_send_command_packet_now()) return;
4931 
4932     // global/non-connection oriented commands
4933 
4934 
4935 #ifdef ENABLE_CLASSIC
4936     // general gap classic
4937     done = hci_run_general_gap_classic();
4938     if (done) return;
4939 #endif
4940 
4941 #ifdef ENABLE_BLE
4942     // general gap le
4943     done = hci_run_general_gap_le();
4944     if (done) return;
4945 #endif
4946 
4947     // send pending HCI commands
4948     done = hci_run_general_pending_commands();
4949     if (done) return;
4950 
4951     // stack state sub statemachines
4952     hci_connection_t * connection;
4953     switch (hci_stack->state){
4954         case HCI_STATE_INITIALIZING:
4955             hci_initializing_run();
4956             break;
4957 
4958         case HCI_STATE_HALTING:
4959 
4960             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4961             switch (hci_stack->substate){
4962                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4963                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4964 
4965 #ifdef ENABLE_BLE
4966 #ifdef ENABLE_LE_CENTRAL
4967                     // free whitelist entries
4968                     {
4969                         btstack_linked_list_iterator_t lit;
4970                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4971                         while (btstack_linked_list_iterator_has_next(&lit)){
4972                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4973                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4974                             btstack_memory_whitelist_entry_free(entry);
4975                         }
4976                     }
4977 #endif
4978 #endif
4979                     // close all open connections
4980                     connection =  (hci_connection_t *) hci_stack->connections;
4981                     if (connection){
4982                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4983                         if (!hci_can_send_command_packet_now()) return;
4984 
4985                         // check state
4986                         if (connection->state == SENT_DISCONNECT) return;
4987                         connection->state = SENT_DISCONNECT;
4988 
4989                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4990 
4991                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4992                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4993 
4994                         // ... which would be ignored anyway as we shutdown (free) the connection now
4995                         hci_shutdown_connection(connection);
4996 
4997                         // finally, send the disconnect command
4998                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4999                         return;
5000                     }
5001 
5002                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5003                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5004                         log_info("HCI_STATE_HALTING: wait 50 ms");
5005                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5006                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5007                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5008                         btstack_run_loop_add_timer(&hci_stack->timeout);
5009                         break;
5010                     }
5011 
5012                     /* fall through */
5013 
5014                 case HCI_HALTING_CLOSE:
5015                     log_info("HCI_STATE_HALTING, calling off");
5016 
5017                     // switch mode
5018                     hci_power_control_off();
5019 
5020                     log_info("HCI_STATE_HALTING, emitting state");
5021                     hci_emit_state();
5022                     log_info("HCI_STATE_HALTING, done");
5023                     break;
5024 
5025                 case HCI_HALTING_W4_TIMER:
5026                     // keep waiting
5027 
5028                     break;
5029                 default:
5030                     break;
5031             }
5032 
5033             break;
5034 
5035         case HCI_STATE_FALLING_ASLEEP:
5036             switch(hci_stack->substate) {
5037                 case HCI_FALLING_ASLEEP_DISCONNECT:
5038                     log_info("HCI_STATE_FALLING_ASLEEP");
5039                     // close all open connections
5040                     connection =  (hci_connection_t *) hci_stack->connections;
5041                     if (connection){
5042 
5043                         // send disconnect
5044                         if (!hci_can_send_command_packet_now()) return;
5045 
5046                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5047                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5048 
5049                         // send disconnected event right away - causes higher layer connections to get closed, too.
5050                         hci_shutdown_connection(connection);
5051                         return;
5052                     }
5053 
5054                     if (hci_classic_supported()){
5055                         // disable page and inquiry scan
5056                         if (!hci_can_send_command_packet_now()) return;
5057 
5058                         log_info("HCI_STATE_HALTING, disabling inq scans");
5059                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5060 
5061                         // continue in next sub state
5062                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5063                         break;
5064                     }
5065 
5066                     /* fall through */
5067 
5068                 case HCI_FALLING_ASLEEP_COMPLETE:
5069                     log_info("HCI_STATE_HALTING, calling sleep");
5070                     // switch mode
5071                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5072                     hci_emit_state();
5073                     break;
5074 
5075                 default:
5076                     break;
5077             }
5078             break;
5079 
5080         default:
5081             break;
5082     }
5083 }
5084 
5085 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5086     // house-keeping
5087 
5088 #ifdef ENABLE_CLASSIC
5089     bd_addr_t addr;
5090     hci_connection_t * conn;
5091 #endif
5092 #ifdef ENABLE_LE_CENTRAL
5093     uint8_t initiator_filter_policy;
5094 #endif
5095 
5096     uint16_t opcode = little_endian_read_16(packet, 0);
5097     switch (opcode) {
5098         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5099             hci_stack->loopback_mode = packet[3];
5100             break;
5101 
5102 #ifdef ENABLE_CLASSIC
5103         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5104             reverse_bd_addr(&packet[3], addr);
5105             log_info("Create_connection to %s", bd_addr_to_str(addr));
5106 
5107             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5108             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5109                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5110                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5111             }
5112 
5113             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5114             if (!conn) {
5115                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5116                 if (!conn) {
5117                     // notify client that alloc failed
5118                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5119                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5120                 }
5121                 conn->state = SEND_CREATE_CONNECTION;
5122                 conn->role  = HCI_ROLE_MASTER;
5123             }
5124 
5125             conn->con_handle = HCI_CON_HANDLE_INVALID;
5126             conn->role = HCI_ROLE_INVALID;
5127 
5128             log_info("conn state %u", conn->state);
5129             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5130             switch (conn->state) {
5131                 // if connection active exists
5132                 case OPEN:
5133                     // and OPEN, emit connection complete command
5134                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5135                     // packet not sent to controller
5136                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5137                 case RECEIVED_DISCONNECTION_COMPLETE:
5138                     // create connection triggered in disconnect complete event, let's do it now
5139                     break;
5140                 case SEND_CREATE_CONNECTION:
5141                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5142                     break;
5143                 default:
5144                     // otherwise, just ignore as it is already in the open process
5145                     // packet not sent to controller
5146                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5147             }
5148             conn->state = SENT_CREATE_CONNECTION;
5149 
5150             // track outgoing connection
5151             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5152             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5153             break;
5154         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5155             if (hci_stack->link_key_db) {
5156                 reverse_bd_addr(&packet[3], addr);
5157                 hci_stack->link_key_db->delete_link_key(addr);
5158             }
5159             break;
5160 
5161 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5162         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5163             // setup_synchronous_connection? Voice setting at offset 22
5164             // TODO: compare to current setting if sco connection already active
5165             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5166             break;
5167         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5168             // accept_synchronus_connection? Voice setting at offset 18
5169             // TODO: compare to current setting if sco connection already active
5170             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5171             break;
5172 #endif
5173 #endif
5174 
5175 #ifdef ENABLE_BLE
5176         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5177             hci_stack->le_random_address_set = 1;
5178             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5179             break;
5180 #ifdef ENABLE_LE_PERIPHERAL
5181         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5182             hci_stack->le_advertisements_active = packet[3] != 0;
5183             break;
5184 #endif
5185 #ifdef ENABLE_LE_CENTRAL
5186         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5187             // white list used?
5188             initiator_filter_policy = packet[7];
5189             switch (initiator_filter_policy) {
5190                 case 0:
5191                     // whitelist not used
5192                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5193                     break;
5194                 case 1:
5195                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5196                     break;
5197                 default:
5198                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5199                     break;
5200             }
5201             // track outgoing connection
5202             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5203             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5204             break;
5205         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5206             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5207             break;
5208 #endif
5209 #endif
5210         default:
5211             break;
5212     }
5213 
5214     hci_stack->num_cmd_packets--;
5215 
5216     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5217     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5218     if (err != 0){
5219         return ERROR_CODE_HARDWARE_FAILURE;
5220     }
5221     return ERROR_CODE_SUCCESS;
5222 }
5223 
5224 // disconnect because of security block
5225 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5226     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5227     if (!connection) return;
5228     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5229 }
5230 
5231 
5232 // Configure Secure Simple Pairing
5233 
5234 #ifdef ENABLE_CLASSIC
5235 
5236 // enable will enable SSP during init
5237 void gap_ssp_set_enable(int enable){
5238     hci_stack->ssp_enable = enable;
5239 }
5240 
5241 static int hci_local_ssp_activated(void){
5242     return gap_ssp_supported() && hci_stack->ssp_enable;
5243 }
5244 
5245 // if set, BTstack will respond to io capability request using authentication requirement
5246 void gap_ssp_set_io_capability(int io_capability){
5247     hci_stack->ssp_io_capability = io_capability;
5248 }
5249 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5250     hci_stack->ssp_authentication_requirement = authentication_requirement;
5251 }
5252 
5253 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5254 void gap_ssp_set_auto_accept(int auto_accept){
5255     hci_stack->ssp_auto_accept = auto_accept;
5256 }
5257 
5258 void gap_secure_connections_enable(bool enable){
5259     hci_stack->secure_connections_enable = enable;
5260 }
5261 
5262 #endif
5263 
5264 // va_list part of hci_send_cmd
5265 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5266     if (!hci_can_send_command_packet_now()){
5267         log_error("hci_send_cmd called but cannot send packet now");
5268         return ERROR_CODE_COMMAND_DISALLOWED;
5269     }
5270 
5271     // for HCI INITIALIZATION
5272     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5273     hci_stack->last_cmd_opcode = cmd->opcode;
5274 
5275     hci_reserve_packet_buffer();
5276     uint8_t * packet = hci_stack->hci_packet_buffer;
5277     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5278     uint8_t status = hci_send_cmd_packet(packet, size);
5279 
5280     // release packet buffer on error or for synchronous transport implementations
5281     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5282         hci_release_packet_buffer();
5283         hci_emit_transport_packet_sent();
5284     }
5285 
5286     return status;
5287 }
5288 
5289 /**
5290  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5291  */
5292 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5293     va_list argptr;
5294     va_start(argptr, cmd);
5295     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5296     va_end(argptr);
5297     return status;
5298 }
5299 
5300 // Create various non-HCI events.
5301 // TODO: generalize, use table similar to hci_create_command
5302 
5303 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5304     // dump packet
5305     if (dump) {
5306         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5307     }
5308 
5309     // dispatch to all event handlers
5310     btstack_linked_list_iterator_t it;
5311     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5312     while (btstack_linked_list_iterator_has_next(&it)){
5313         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5314         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5315     }
5316 }
5317 
5318 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5319     if (!hci_stack->acl_packet_handler) return;
5320     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5321 }
5322 
5323 #ifdef ENABLE_CLASSIC
5324 static void hci_notify_if_sco_can_send_now(void){
5325     // notify SCO sender if waiting
5326     if (!hci_stack->sco_waiting_for_can_send_now) return;
5327     if (hci_can_send_sco_packet_now()){
5328         hci_stack->sco_waiting_for_can_send_now = 0;
5329         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5330         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5331         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5332     }
5333 }
5334 
5335 // parsing end emitting has been merged to reduce code size
5336 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5337     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5338 
5339     uint8_t * eir_data;
5340     ad_context_t context;
5341     const uint8_t * name;
5342     uint8_t         name_len;
5343 
5344     if (size < 3) return;
5345 
5346     int event_type = hci_event_packet_get_type(packet);
5347     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5348     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5349 
5350     switch (event_type){
5351         case HCI_EVENT_INQUIRY_RESULT:
5352         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5353             if (size != (3 + (num_responses * 14))) return;
5354             break;
5355         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5356             if (size != 257) return;
5357             if (num_responses != 1) return;
5358             break;
5359         default:
5360             return;
5361     }
5362 
5363     // event[1] is set at the end
5364     int i;
5365     for (i=0; i<num_responses;i++){
5366         memset(event, 0, sizeof(event));
5367         event[0] = GAP_EVENT_INQUIRY_RESULT;
5368         uint8_t event_size = 27;    // if name is not set by EIR
5369 
5370         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5371         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5372         (void)memcpy(&event[9],
5373                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5374                      3); // class of device
5375         (void)memcpy(&event[12],
5376                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5377                      2); // clock offset
5378 
5379         switch (event_type){
5380             case HCI_EVENT_INQUIRY_RESULT:
5381                 // 14,15,16,17 = 0, size 18
5382                 break;
5383             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5384                 event[14] = 1;
5385                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5386                 // 16,17 = 0, size 18
5387                 break;
5388             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5389                 event[14] = 1;
5390                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5391                 // EIR packets only contain a single inquiry response
5392                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5393                 name = NULL;
5394                 // Iterate over EIR data
5395                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5396                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5397                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5398                     const uint8_t * data = ad_iterator_get_data(&context);
5399                     // Prefer Complete Local Name over Shortened Local Name
5400                     switch (data_type){
5401                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5402                             if (name) continue;
5403                             /* fall through */
5404                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5405                             name = data;
5406                             name_len = data_size;
5407                             break;
5408                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5409                             if (data_size != 8) break;
5410                             event[16] = 1;
5411                             memcpy(&event[17], data, 8);
5412                             break;
5413                         default:
5414                             break;
5415                     }
5416                 }
5417                 if (name){
5418                     event[25] = 1;
5419                     // truncate name if needed
5420                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5421                     event[26] = len;
5422                     (void)memcpy(&event[27], name, len);
5423                     event_size += len;
5424                 }
5425                 break;
5426             default:
5427                 return;
5428         }
5429         event[1] = event_size - 2;
5430         hci_emit_event(event, event_size, 1);
5431     }
5432 }
5433 #endif
5434 
5435 void hci_emit_state(void){
5436     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5437     uint8_t event[3];
5438     event[0] = BTSTACK_EVENT_STATE;
5439     event[1] = sizeof(event) - 2u;
5440     event[2] = hci_stack->state;
5441     hci_emit_event(event, sizeof(event), 1);
5442 }
5443 
5444 #ifdef ENABLE_CLASSIC
5445 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5446     uint8_t event[13];
5447     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5448     event[1] = sizeof(event) - 2;
5449     event[2] = status;
5450     little_endian_store_16(event, 3, con_handle);
5451     reverse_bd_addr(address, &event[5]);
5452     event[11] = 1; // ACL connection
5453     event[12] = 0; // encryption disabled
5454     hci_emit_event(event, sizeof(event), 1);
5455 }
5456 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5457     if (disable_l2cap_timeouts) return;
5458     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5459     uint8_t event[4];
5460     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5461     event[1] = sizeof(event) - 2;
5462     little_endian_store_16(event, 2, conn->con_handle);
5463     hci_emit_event(event, sizeof(event), 1);
5464 }
5465 #endif
5466 
5467 #ifdef ENABLE_BLE
5468 #ifdef ENABLE_LE_CENTRAL
5469 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){
5470     uint8_t event[21];
5471     event[0] = HCI_EVENT_LE_META;
5472     event[1] = sizeof(event) - 2u;
5473     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5474     event[3] = status;
5475     little_endian_store_16(event, 4, con_handle);
5476     event[6] = 0; // TODO: role
5477     event[7] = address_type;
5478     reverse_bd_addr(address, &event[8]);
5479     little_endian_store_16(event, 14, 0); // interval
5480     little_endian_store_16(event, 16, 0); // latency
5481     little_endian_store_16(event, 18, 0); // supervision timeout
5482     event[20] = 0; // master clock accuracy
5483     hci_emit_event(event, sizeof(event), 1);
5484 }
5485 #endif
5486 #endif
5487 
5488 static void hci_emit_transport_packet_sent(void){
5489     // notify upper stack that it might be possible to send again
5490     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5491     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5492 }
5493 
5494 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5495     uint8_t event[6];
5496     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5497     event[1] = sizeof(event) - 2u;
5498     event[2] = 0; // status = OK
5499     little_endian_store_16(event, 3, con_handle);
5500     event[5] = reason;
5501     hci_emit_event(event, sizeof(event), 1);
5502 }
5503 
5504 static void hci_emit_nr_connections_changed(void){
5505     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5506     uint8_t event[3];
5507     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5508     event[1] = sizeof(event) - 2u;
5509     event[2] = nr_hci_connections();
5510     hci_emit_event(event, sizeof(event), 1);
5511 }
5512 
5513 static void hci_emit_hci_open_failed(void){
5514     log_info("BTSTACK_EVENT_POWERON_FAILED");
5515     uint8_t event[2];
5516     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5517     event[1] = sizeof(event) - 2u;
5518     hci_emit_event(event, sizeof(event), 1);
5519 }
5520 
5521 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5522     log_info("hci_emit_dedicated_bonding_result %u ", status);
5523     uint8_t event[9];
5524     int pos = 0;
5525     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5526     event[pos++] = sizeof(event) - 2u;
5527     event[pos++] = status;
5528     reverse_bd_addr(address, &event[pos]);
5529     hci_emit_event(event, sizeof(event), 1);
5530 }
5531 
5532 
5533 #ifdef ENABLE_CLASSIC
5534 
5535 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5536     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5537     uint8_t event[5];
5538     int pos = 0;
5539     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5540     event[pos++] = sizeof(event) - 2;
5541     little_endian_store_16(event, 2, con_handle);
5542     pos += 2;
5543     event[pos++] = level;
5544     hci_emit_event(event, sizeof(event), 1);
5545 }
5546 
5547 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5548     if (!connection) return LEVEL_0;
5549     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5550     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5551     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5552     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5553     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5554     // LEVEL 4 always requires 128 bit encrytion key size
5555     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5556         security_level = LEVEL_3;
5557     }
5558     return security_level;
5559 }
5560 
5561 static void hci_emit_discoverable_enabled(uint8_t enabled){
5562     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5563     uint8_t event[3];
5564     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5565     event[1] = sizeof(event) - 2;
5566     event[2] = enabled;
5567     hci_emit_event(event, sizeof(event), 1);
5568 }
5569 
5570 // query if remote side supports eSCO
5571 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5572     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5573     if (!connection) return false;
5574     return (connection->remote_supported_features[0] & 1) != 0;
5575 }
5576 
5577 static bool hci_ssp_supported(hci_connection_t * connection){
5578     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5579     return (connection->bonding_flags & mask) == mask;
5580 }
5581 
5582 // query if remote side supports SSP
5583 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5584     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5585     if (!connection) return false;
5586     return hci_ssp_supported(connection) ? 1 : 0;
5587 }
5588 
5589 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5590     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5591 }
5592 
5593 /**
5594  * Check if remote supported features query has completed
5595  */
5596 bool hci_remote_features_available(hci_con_handle_t handle){
5597     hci_connection_t * connection = hci_connection_for_handle(handle);
5598     if (!connection) return false;
5599     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5600 }
5601 
5602 /**
5603  * Trigger remote supported features query
5604  */
5605 void hci_remote_features_query(hci_con_handle_t con_handle){
5606     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5607     if (!connection) return;
5608     if ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) return;
5609     connection->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5610     hci_run();
5611 }
5612 
5613 // GAP API
5614 /**
5615  * @bbrief enable/disable bonding. default is enabled
5616  * @praram enabled
5617  */
5618 void gap_set_bondable_mode(int enable){
5619     hci_stack->bondable = enable ? 1 : 0;
5620 }
5621 /**
5622  * @brief Get bondable mode.
5623  * @return 1 if bondable
5624  */
5625 int gap_get_bondable_mode(void){
5626     return hci_stack->bondable;
5627 }
5628 
5629 /**
5630  * @brief map link keys to security levels
5631  */
5632 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5633     switch (link_key_type){
5634         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5635             return LEVEL_4;
5636         case COMBINATION_KEY:
5637         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5638             return LEVEL_3;
5639         default:
5640             return LEVEL_2;
5641     }
5642 }
5643 
5644 /**
5645  * @brief map link keys to secure connection yes/no
5646  */
5647 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5648     switch (link_key_type){
5649         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5650         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5651             return 1;
5652         default:
5653             return 0;
5654     }
5655 }
5656 
5657 /**
5658  * @brief map link keys to authenticated
5659  */
5660 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5661     switch (link_key_type){
5662         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5663         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5664             return 1;
5665         default:
5666             return 0;
5667     }
5668 }
5669 
5670 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5671     log_info("gap_mitm_protection_required_for_security_level %u", level);
5672     return level > LEVEL_2;
5673 }
5674 
5675 /**
5676  * @brief get current security level
5677  */
5678 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5679     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5680     if (!connection) return LEVEL_0;
5681     return gap_security_level_for_connection(connection);
5682 }
5683 
5684 /**
5685  * @brief request connection to device to
5686  * @result GAP_AUTHENTICATION_RESULT
5687  */
5688 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5689     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5690     if (!connection){
5691         hci_emit_security_level(con_handle, LEVEL_0);
5692         return;
5693     }
5694 
5695     btstack_assert(hci_is_le_connection(connection) == false);
5696 
5697     // 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)
5698     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5699     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5700         requested_level = LEVEL_4;
5701     }
5702 
5703     gap_security_level_t current_level = gap_security_level(con_handle);
5704     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5705         requested_level, connection->requested_security_level, current_level);
5706 
5707     // authentication active if authentication request was sent or planned level > 0
5708     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5709     if (authentication_active){
5710         // authentication already active
5711         if (connection->requested_security_level < requested_level){
5712             // increase requested level as new level is higher
5713             // TODO: handle re-authentication when done
5714             connection->requested_security_level = requested_level;
5715         }
5716     } else {
5717         // no request active, notify if security sufficient
5718         if (requested_level <= current_level){
5719             hci_emit_security_level(con_handle, current_level);
5720             return;
5721         }
5722 
5723         // store request
5724         connection->requested_security_level = requested_level;
5725 
5726         // start to authenticate connection
5727         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5728         hci_run();
5729     }
5730 }
5731 
5732 /**
5733  * @brief start dedicated bonding with device. disconnect after bonding
5734  * @param device
5735  * @param request MITM protection
5736  * @result GAP_DEDICATED_BONDING_COMPLETE
5737  */
5738 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5739 
5740     // create connection state machine
5741     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5742 
5743     if (!connection){
5744         return BTSTACK_MEMORY_ALLOC_FAILED;
5745     }
5746 
5747     // delete linkn key
5748     gap_drop_link_key_for_bd_addr(device);
5749 
5750     // configure LEVEL_2/3, dedicated bonding
5751     connection->state = SEND_CREATE_CONNECTION;
5752     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5753     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5754     connection->bonding_flags = BONDING_DEDICATED;
5755 
5756     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5757 
5758     // handle: connnection failure (connection complete != ok)
5759     // handle: authentication failure
5760     // handle: disconnect on done
5761 
5762     hci_run();
5763 
5764     return 0;
5765 }
5766 
5767 void gap_set_local_name(const char * local_name){
5768     hci_stack->local_name = local_name;
5769     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5770     // also update EIR if not set by user
5771     if (hci_stack->eir_data == NULL){
5772         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5773     }
5774     hci_run();
5775 }
5776 #endif
5777 
5778 
5779 #ifdef ENABLE_BLE
5780 
5781 #ifdef ENABLE_LE_CENTRAL
5782 void gap_start_scan(void){
5783     hci_stack->le_scanning_enabled = true;
5784     hci_run();
5785 }
5786 
5787 void gap_stop_scan(void){
5788     hci_stack->le_scanning_enabled = false;
5789     hci_run();
5790 }
5791 
5792 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5793     hci_stack->le_scan_type          = scan_type;
5794     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5795     hci_stack->le_scan_interval      = scan_interval;
5796     hci_stack->le_scan_window        = scan_window;
5797     hci_stack->le_scanning_param_update = true;
5798     hci_run();
5799 }
5800 
5801 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5802     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5803 }
5804 
5805 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5806     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5807     if (!conn){
5808         // disallow if le connection is already outgoing
5809         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5810             log_error("le connection already active");
5811             return ERROR_CODE_COMMAND_DISALLOWED;
5812         }
5813 
5814         log_info("gap_connect: no connection exists yet, creating context");
5815         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5816         if (!conn){
5817             // notify client that alloc failed
5818             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5819             log_info("gap_connect: failed to alloc hci_connection_t");
5820             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5821         }
5822 
5823         // set le connecting state
5824         if (hci_is_le_connection_type(addr_type)){
5825             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5826         }
5827 
5828         conn->state = SEND_CREATE_CONNECTION;
5829         log_info("gap_connect: send create connection next");
5830         hci_run();
5831         return ERROR_CODE_SUCCESS;
5832     }
5833 
5834     if (!hci_is_le_connection(conn) ||
5835         (conn->state == SEND_CREATE_CONNECTION) ||
5836         (conn->state == SENT_CREATE_CONNECTION)) {
5837         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5838         log_error("gap_connect: classic connection or connect is already being created");
5839         return GATT_CLIENT_IN_WRONG_STATE;
5840     }
5841 
5842     // check if connection was just disconnected
5843     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5844         log_info("gap_connect: send create connection (again)");
5845         conn->state = SEND_CREATE_CONNECTION;
5846         hci_run();
5847         return ERROR_CODE_SUCCESS;
5848     }
5849 
5850     log_info("gap_connect: context exists with state %u", conn->state);
5851     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5852     hci_run();
5853     return ERROR_CODE_SUCCESS;
5854 }
5855 
5856 // @assumption: only a single outgoing LE Connection exists
5857 static hci_connection_t * gap_get_outgoing_connection(void){
5858     btstack_linked_item_t *it;
5859     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5860         hci_connection_t * conn = (hci_connection_t *) it;
5861         if (!hci_is_le_connection(conn)) continue;
5862         switch (conn->state){
5863             case SEND_CREATE_CONNECTION:
5864             case SENT_CREATE_CONNECTION:
5865             case SENT_CANCEL_CONNECTION:
5866                 return conn;
5867             default:
5868                 break;
5869         };
5870     }
5871     return NULL;
5872 }
5873 
5874 uint8_t gap_connect_cancel(void){
5875     hci_connection_t * conn = gap_get_outgoing_connection();
5876     if (!conn) return 0;
5877     switch (conn->state){
5878         case SEND_CREATE_CONNECTION:
5879             // skip sending create connection and emit event instead
5880             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5881             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5882             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5883             btstack_memory_hci_connection_free( conn );
5884             break;
5885         case SENT_CREATE_CONNECTION:
5886             // request to send cancel connection
5887             conn->state = SEND_CANCEL_CONNECTION;
5888             hci_run();
5889             break;
5890         default:
5891             break;
5892     }
5893     return 0;
5894 }
5895 #endif
5896 
5897 #ifdef ENABLE_LE_CENTRAL
5898 /**
5899  * @brief Set connection parameters for outgoing connections
5900  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5901  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5902  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5903  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5904  * @param conn_latency, default: 4
5905  * @param supervision_timeout (unit: 10ms), default: 720 ms
5906  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5907  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5908  */
5909 
5910 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5911     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5912     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5913     hci_stack->le_connection_scan_interval = conn_scan_interval;
5914     hci_stack->le_connection_scan_window = conn_scan_window;
5915     hci_stack->le_connection_interval_min = conn_interval_min;
5916     hci_stack->le_connection_interval_max = conn_interval_max;
5917     hci_stack->le_connection_latency = conn_latency;
5918     hci_stack->le_supervision_timeout = supervision_timeout;
5919     hci_stack->le_minimum_ce_length = min_ce_length;
5920     hci_stack->le_maximum_ce_length = max_ce_length;
5921 }
5922 #endif
5923 
5924 /**
5925  * @brief Updates the connection parameters for a given LE connection
5926  * @param handle
5927  * @param conn_interval_min (unit: 1.25ms)
5928  * @param conn_interval_max (unit: 1.25ms)
5929  * @param conn_latency
5930  * @param supervision_timeout (unit: 10ms)
5931  * @returns 0 if ok
5932  */
5933 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5934     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5935     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5936     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5937     connection->le_conn_interval_min = conn_interval_min;
5938     connection->le_conn_interval_max = conn_interval_max;
5939     connection->le_conn_latency = conn_latency;
5940     connection->le_supervision_timeout = supervision_timeout;
5941     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5942     hci_run();
5943     return 0;
5944 }
5945 
5946 /**
5947  * @brief Request an update of the connection parameter for a given LE connection
5948  * @param handle
5949  * @param conn_interval_min (unit: 1.25ms)
5950  * @param conn_interval_max (unit: 1.25ms)
5951  * @param conn_latency
5952  * @param supervision_timeout (unit: 10ms)
5953  * @returns 0 if ok
5954  */
5955 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5956     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5957     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5958     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5959     connection->le_conn_interval_min = conn_interval_min;
5960     connection->le_conn_interval_max = conn_interval_max;
5961     connection->le_conn_latency = conn_latency;
5962     connection->le_supervision_timeout = supervision_timeout;
5963     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5964     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5965     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5966     return 0;
5967 }
5968 
5969 #ifdef ENABLE_LE_PERIPHERAL
5970 
5971 /**
5972  * @brief Set Advertisement Data
5973  * @param advertising_data_length
5974  * @param advertising_data (max 31 octets)
5975  * @note data is not copied, pointer has to stay valid
5976  */
5977 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5978     hci_stack->le_advertisements_data_len = advertising_data_length;
5979     hci_stack->le_advertisements_data = advertising_data;
5980     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5981     hci_run();
5982 }
5983 
5984 /**
5985  * @brief Set Scan Response Data
5986  * @param advertising_data_length
5987  * @param advertising_data (max 31 octets)
5988  * @note data is not copied, pointer has to stay valid
5989  */
5990 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5991     hci_stack->le_scan_response_data_len = scan_response_data_length;
5992     hci_stack->le_scan_response_data = scan_response_data;
5993     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5994     hci_run();
5995 }
5996 
5997 /**
5998  * @brief Set Advertisement Parameters
5999  * @param adv_int_min
6000  * @param adv_int_max
6001  * @param adv_type
6002  * @param direct_address_type
6003  * @param direct_address
6004  * @param channel_map
6005  * @param filter_policy
6006  *
6007  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6008  */
6009  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6010     uint8_t direct_address_typ, bd_addr_t direct_address,
6011     uint8_t channel_map, uint8_t filter_policy) {
6012 
6013     hci_stack->le_advertisements_interval_min = adv_int_min;
6014     hci_stack->le_advertisements_interval_max = adv_int_max;
6015     hci_stack->le_advertisements_type = adv_type;
6016     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6017     hci_stack->le_advertisements_channel_map = channel_map;
6018     hci_stack->le_advertisements_filter_policy = filter_policy;
6019     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6020                  6);
6021 
6022     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6023     hci_run();
6024  }
6025 
6026 /**
6027  * @brief Enable/Disable Advertisements
6028  * @param enabled
6029  */
6030 void gap_advertisements_enable(int enabled){
6031     hci_stack->le_advertisements_enabled = enabled != 0;
6032     hci_update_advertisements_enabled_for_current_roles();
6033     hci_run();
6034 }
6035 
6036 #endif
6037 
6038 void hci_le_set_own_address_type(uint8_t own_address_type){
6039     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6040     if (own_address_type == hci_stack->le_own_addr_type) return;
6041     hci_stack->le_own_addr_type = own_address_type;
6042 
6043 #ifdef ENABLE_LE_PERIPHERAL
6044     // update advertisement parameters, too
6045     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6046     hci_run();
6047 #endif
6048 #ifdef ENABLE_LE_CENTRAL
6049     // note: we don't update scan parameters or modify ongoing connection attempts
6050 #endif
6051 }
6052 
6053 #endif
6054 
6055 uint8_t gap_disconnect(hci_con_handle_t handle){
6056     hci_connection_t * conn = hci_connection_for_handle(handle);
6057     if (!conn){
6058         hci_emit_disconnection_complete(handle, 0);
6059         return 0;
6060     }
6061     // ignore if already disconnected
6062     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6063         return 0;
6064     }
6065     conn->state = SEND_DISCONNECT;
6066     hci_run();
6067     return 0;
6068 }
6069 
6070 int gap_read_rssi(hci_con_handle_t con_handle){
6071     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6072     if (hci_connection == NULL) return 0;
6073     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6074     hci_run();
6075     return 1;
6076 }
6077 
6078 /**
6079  * @brief Get connection type
6080  * @param con_handle
6081  * @result connection_type
6082  */
6083 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6084     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6085     if (!conn) return GAP_CONNECTION_INVALID;
6086     switch (conn->address_type){
6087         case BD_ADDR_TYPE_LE_PUBLIC:
6088         case BD_ADDR_TYPE_LE_RANDOM:
6089             return GAP_CONNECTION_LE;
6090         case BD_ADDR_TYPE_SCO:
6091             return GAP_CONNECTION_SCO;
6092         case BD_ADDR_TYPE_ACL:
6093             return GAP_CONNECTION_ACL;
6094         default:
6095             return GAP_CONNECTION_INVALID;
6096     }
6097 }
6098 
6099 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6100     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6101     if (!conn) return HCI_ROLE_INVALID;
6102     return (hci_role_t) conn->role;
6103 }
6104 
6105 
6106 #ifdef ENABLE_CLASSIC
6107 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6108     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6109     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6110     conn->request_role = role;
6111     hci_run();
6112     return ERROR_CODE_SUCCESS;
6113 }
6114 #endif
6115 
6116 #ifdef ENABLE_BLE
6117 
6118 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){
6119     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6120     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6121 
6122     conn->le_phy_update_all_phys    = all_phys;
6123     conn->le_phy_update_tx_phys     = tx_phys;
6124     conn->le_phy_update_rx_phys     = rx_phys;
6125     conn->le_phy_update_phy_options = phy_options;
6126 
6127     hci_run();
6128 
6129     return 0;
6130 }
6131 
6132 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6133     // check if already in list
6134     btstack_linked_list_iterator_t it;
6135     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6136     while (btstack_linked_list_iterator_has_next(&it)) {
6137         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6138         if (entry->address_type != address_type) {
6139             continue;
6140         }
6141         if (memcmp(entry->address, address, 6) != 0) {
6142             continue;
6143         }
6144 		// disallow if already scheduled to add
6145 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6146 			return ERROR_CODE_COMMAND_DISALLOWED;
6147 		}
6148 		// still on controller, but scheduled to remove -> re-add
6149 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6150 		return ERROR_CODE_SUCCESS;
6151     }
6152     // alloc and add to list
6153     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6154     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6155     entry->address_type = address_type;
6156     (void)memcpy(entry->address, address, 6);
6157     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6158     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6159     return ERROR_CODE_SUCCESS;
6160 }
6161 
6162 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6163     btstack_linked_list_iterator_t it;
6164     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6165     while (btstack_linked_list_iterator_has_next(&it)){
6166         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6167         if (entry->address_type != address_type) {
6168             continue;
6169         }
6170         if (memcmp(entry->address, address, 6) != 0) {
6171             continue;
6172         }
6173         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6174             // remove from controller if already present
6175             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6176         }  else {
6177             // directly remove entry from whitelist
6178             btstack_linked_list_iterator_remove(&it);
6179             btstack_memory_whitelist_entry_free(entry);
6180         }
6181         return ERROR_CODE_SUCCESS;
6182     }
6183     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6184 }
6185 
6186 static void hci_whitelist_clear(void){
6187     btstack_linked_list_iterator_t it;
6188     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6189     while (btstack_linked_list_iterator_has_next(&it)){
6190         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6191         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6192             // remove from controller if already present
6193             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6194             continue;
6195         }
6196         // directly remove entry from whitelist
6197         btstack_linked_list_iterator_remove(&it);
6198         btstack_memory_whitelist_entry_free(entry);
6199     }
6200 }
6201 
6202 /**
6203  * @brief Clear Whitelist
6204  * @returns 0 if ok
6205  */
6206 uint8_t gap_whitelist_clear(void){
6207     hci_whitelist_clear();
6208     hci_run();
6209     return ERROR_CODE_SUCCESS;
6210 }
6211 
6212 /**
6213  * @brief Add Device to Whitelist
6214  * @param address_typ
6215  * @param address
6216  * @returns 0 if ok
6217  */
6218 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6219     uint8_t status = hci_whitelist_add(address_type, address);
6220     if (status){
6221         return status;
6222     }
6223     hci_run();
6224     return ERROR_CODE_SUCCESS;
6225 }
6226 
6227 /**
6228  * @brief Remove Device from Whitelist
6229  * @param address_typ
6230  * @param address
6231  * @returns 0 if ok
6232  */
6233 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6234     uint8_t status = hci_whitelist_remove(address_type, address);
6235     if (status){
6236         return status;
6237     }
6238     hci_run();
6239     return ERROR_CODE_SUCCESS;
6240 }
6241 
6242 #ifdef ENABLE_LE_CENTRAL
6243 /**
6244  *  @brief Connect with Whitelist
6245  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6246  *  @returns - if ok
6247  */
6248 uint8_t gap_connect_with_whitelist(void){
6249     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6250         return ERROR_CODE_COMMAND_DISALLOWED;
6251     }
6252     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6253     hci_run();
6254     return ERROR_CODE_SUCCESS;
6255 }
6256 
6257 /**
6258  * @brief Auto Connection Establishment - Start Connecting to device
6259  * @param address_typ
6260  * @param address
6261  * @returns 0 if ok
6262  */
6263 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6264     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6265         return ERROR_CODE_COMMAND_DISALLOWED;
6266     }
6267 
6268     uint8_t status = hci_whitelist_add(address_type, address);
6269     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6270         return status;
6271     }
6272 
6273     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6274 
6275     hci_run();
6276     return ERROR_CODE_SUCCESS;
6277 }
6278 
6279 /**
6280  * @brief Auto Connection Establishment - Stop Connecting to device
6281  * @param address_typ
6282  * @param address
6283  * @returns 0 if ok
6284  */
6285 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6286     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6287         return ERROR_CODE_COMMAND_DISALLOWED;
6288     }
6289 
6290     hci_whitelist_remove(address_type, address);
6291     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6292         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6293     }
6294     hci_run();
6295     return 0;
6296 }
6297 
6298 /**
6299  * @brief Auto Connection Establishment - Stop everything
6300  * @note  Convenience function to stop all active auto connection attempts
6301  */
6302 uint8_t gap_auto_connection_stop_all(void){
6303     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6304         return ERROR_CODE_COMMAND_DISALLOWED;
6305     }
6306     hci_whitelist_clear();
6307     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6308     hci_run();
6309     return ERROR_CODE_SUCCESS;
6310 }
6311 
6312 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6313     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6314     if (!conn) return 0;
6315     return conn->le_connection_interval;
6316 }
6317 #endif
6318 #endif
6319 
6320 #ifdef ENABLE_CLASSIC
6321 /**
6322  * @brief Set Extended Inquiry Response data
6323  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6324  * @note has to be done before stack starts up
6325  */
6326 void gap_set_extended_inquiry_response(const uint8_t * data){
6327     hci_stack->eir_data = data;
6328     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6329     hci_run();
6330 }
6331 
6332 /**
6333  * @brief Start GAP Classic Inquiry
6334  * @param duration in 1.28s units
6335  * @return 0 if ok
6336  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6337  */
6338 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6339     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6340     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6341     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6342         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6343     }
6344     hci_stack->inquiry_state = duration_in_1280ms_units;
6345     hci_run();
6346     return 0;
6347 }
6348 
6349 /**
6350  * @brief Stop GAP Classic Inquiry
6351  * @returns 0 if ok
6352  */
6353 int gap_inquiry_stop(void){
6354     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6355         // emit inquiry complete event, before it even started
6356         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6357         hci_emit_event(event, sizeof(event), 1);
6358         return 0;
6359     }
6360     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6361     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6362     hci_run();
6363     return 0;
6364 }
6365 
6366 void gap_inquiry_set_lap(uint32_t lap){
6367     hci_stack->inquiry_lap = lap;
6368 }
6369 
6370 
6371 /**
6372  * @brief Remote Name Request
6373  * @param addr
6374  * @param page_scan_repetition_mode
6375  * @param clock_offset only used when bit 15 is set
6376  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6377  */
6378 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6379     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6380     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6381     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6382     hci_stack->remote_name_clock_offset = clock_offset;
6383     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6384     hci_run();
6385     return 0;
6386 }
6387 
6388 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6389     hci_stack->gap_pairing_state = state;
6390     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6391     hci_run();
6392     return 0;
6393 }
6394 
6395 /**
6396  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6397  * @param addr
6398  * @param pin_data
6399  * @param pin_len
6400  * @return 0 if ok
6401  */
6402 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6403     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6404     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6405     hci_stack->gap_pairing_pin_len = pin_len;
6406     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6407 }
6408 
6409 /**
6410  * @brief Legacy Pairing Pin Code Response
6411  * @param addr
6412  * @param pin
6413  * @return 0 if ok
6414  */
6415 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6416     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6417 }
6418 
6419 /**
6420  * @brief Abort Legacy Pairing
6421  * @param addr
6422  * @param pin
6423  * @return 0 if ok
6424  */
6425 int gap_pin_code_negative(bd_addr_t addr){
6426     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6427     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6428 }
6429 
6430 /**
6431  * @brief SSP Passkey Response
6432  * @param addr
6433  * @param passkey
6434  * @return 0 if ok
6435  */
6436 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6437     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6438     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6439     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6440 }
6441 
6442 /**
6443  * @brief Abort SSP Passkey Entry/Pairing
6444  * @param addr
6445  * @param pin
6446  * @return 0 if ok
6447  */
6448 int gap_ssp_passkey_negative(const bd_addr_t addr){
6449     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6450     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6451 }
6452 
6453 /**
6454  * @brief Accept SSP Numeric Comparison
6455  * @param addr
6456  * @param passkey
6457  * @return 0 if ok
6458  */
6459 int gap_ssp_confirmation_response(const bd_addr_t addr){
6460     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6461     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6462 }
6463 
6464 /**
6465  * @brief Abort SSP Numeric Comparison/Pairing
6466  * @param addr
6467  * @param pin
6468  * @return 0 if ok
6469  */
6470 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6471     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6472     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6473 }
6474 
6475 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6476 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6477     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6478     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6479     connectionSetAuthenticationFlags(conn, flag);
6480     hci_run();
6481     return ERROR_CODE_SUCCESS;
6482 }
6483 #endif
6484 
6485 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6486 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6487     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6488 }
6489 
6490 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6491     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6492 }
6493 #endif
6494 
6495 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6496 /**
6497  * @brief Report Remote OOB Data
6498  * @param bd_addr
6499  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6500  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6501  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6502  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6503  */
6504 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){
6505     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6506     if (connection == NULL) {
6507         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6508     }
6509     connection->classic_oob_c_192 = c_192;
6510     connection->classic_oob_r_192 = r_192;
6511 
6512     // ignore P-256 if not supported by us
6513     if (hci_stack->secure_connections_active){
6514         connection->classic_oob_c_256 = c_256;
6515         connection->classic_oob_r_256 = r_256;
6516     }
6517 
6518     return ERROR_CODE_SUCCESS;
6519 }
6520 /**
6521  * @brief Generate new OOB data
6522  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6523  */
6524 void gap_ssp_generate_oob_data(void){
6525     hci_stack->classic_read_local_oob_data = true;
6526     hci_run();
6527 }
6528 
6529 #endif
6530 
6531 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6532 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6533     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6534     if (connection == NULL) {
6535         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6536     }
6537 
6538     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6539     connection->link_key_type = type;
6540 
6541     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6542 }
6543 
6544 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6545 /**
6546  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6547  * @param inquiry_mode see bluetooth_defines.h
6548  */
6549 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6550     hci_stack->inquiry_mode = inquiry_mode;
6551 }
6552 
6553 /**
6554  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6555  */
6556 void hci_set_sco_voice_setting(uint16_t voice_setting){
6557     hci_stack->sco_voice_setting = voice_setting;
6558 }
6559 
6560 /**
6561  * @brief Get SCO Voice Setting
6562  * @return current voice setting
6563  */
6564 uint16_t hci_get_sco_voice_setting(void){
6565     return hci_stack->sco_voice_setting;
6566 }
6567 
6568 static int hci_have_usb_transport(void){
6569     if (!hci_stack->hci_transport) return 0;
6570     const char * transport_name = hci_stack->hci_transport->name;
6571     if (!transport_name) return 0;
6572     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6573 }
6574 
6575 /** @brief Get SCO packet length for current SCO Voice setting
6576  *  @note  Using SCO packets of the exact length is required for USB transfer
6577  *  @return Length of SCO packets in bytes (not audio frames)
6578  */
6579 uint16_t hci_get_sco_packet_length(void){
6580     uint16_t sco_packet_length = 0;
6581 
6582 #ifdef ENABLE_SCO_OVER_HCI
6583     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6584     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6585 
6586     if (hci_have_usb_transport()){
6587         // see Core Spec for H2 USB Transfer.
6588         // 3 byte SCO header + 24 bytes per connection
6589         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6590         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6591     } else {
6592         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6593         sco_packet_length = 3 + 60 * multiplier;
6594         // assert that it still fits inside an SCO buffer
6595         if (sco_packet_length > hci_stack->sco_data_packet_length){
6596             sco_packet_length = 3 + 60;
6597         }
6598     }
6599 #endif
6600 
6601 #ifdef HAVE_SCO_TRANSPORT
6602     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6603     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6604     sco_packet_length = 3 + 60 * multiplier;
6605 #endif
6606     return sco_packet_length;
6607 }
6608 
6609 /**
6610 * @brief Sets the master/slave policy
6611 * @param policy (0: attempt to become master, 1: let connecting device decide)
6612 */
6613 void hci_set_master_slave_policy(uint8_t policy){
6614     hci_stack->master_slave_policy = policy;
6615 }
6616 
6617 #endif
6618 
6619 HCI_STATE hci_get_state(void){
6620     return hci_stack->state;
6621 }
6622 
6623 #ifdef ENABLE_CLASSIC
6624 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6625     hci_stack->gap_classic_accept_callback = accept_callback;
6626 }
6627 #endif
6628 
6629 /**
6630  * @brief Set callback for Bluetooth Hardware Error
6631  */
6632 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6633     hci_stack->hardware_error_callback = fn;
6634 }
6635 
6636 void hci_disconnect_all(void){
6637     btstack_linked_list_iterator_t it;
6638     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6639     while (btstack_linked_list_iterator_has_next(&it)){
6640         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6641         if (con->state == SENT_DISCONNECT) continue;
6642         con->state = SEND_DISCONNECT;
6643     }
6644     hci_run();
6645 }
6646 
6647 uint16_t hci_get_manufacturer(void){
6648     return hci_stack->manufacturer;
6649 }
6650 
6651 #ifdef ENABLE_BLE
6652 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6653     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6654     if (!hci_con) return NULL;
6655     return &hci_con->sm_connection;
6656 }
6657 
6658 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6659 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6660 #endif
6661 
6662 int gap_encryption_key_size(hci_con_handle_t con_handle){
6663     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6664     if (hci_connection == NULL) return 0;
6665     if (hci_is_le_connection(hci_connection)){
6666 #ifdef ENABLE_BLE
6667         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6668         if (sm_conn->sm_connection_encrypted) {
6669             return sm_conn->sm_actual_encryption_key_size;
6670         }
6671 #endif
6672     } else {
6673 #ifdef ENABLE_CLASSIC
6674         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6675             return hci_connection->encryption_key_size;
6676         }
6677 #endif
6678     }
6679     return 0;
6680 }
6681 
6682 int gap_authenticated(hci_con_handle_t con_handle){
6683     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6684     if (hci_connection == NULL) return 0;
6685 
6686     switch (hci_connection->address_type){
6687 #ifdef ENABLE_BLE
6688         case BD_ADDR_TYPE_LE_PUBLIC:
6689         case BD_ADDR_TYPE_LE_RANDOM:
6690             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6691             return hci_connection->sm_connection.sm_connection_authenticated;
6692 #endif
6693 #ifdef ENABLE_CLASSIC
6694         case BD_ADDR_TYPE_SCO:
6695         case BD_ADDR_TYPE_ACL:
6696             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6697 #endif
6698         default:
6699             return 0;
6700     }
6701 }
6702 
6703 int gap_secure_connection(hci_con_handle_t con_handle){
6704     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6705     if (hci_connection == NULL) return 0;
6706 
6707     switch (hci_connection->address_type){
6708 #ifdef ENABLE_BLE
6709         case BD_ADDR_TYPE_LE_PUBLIC:
6710         case BD_ADDR_TYPE_LE_RANDOM:
6711             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6712             return hci_connection->sm_connection.sm_connection_sc;
6713 #endif
6714 #ifdef ENABLE_CLASSIC
6715         case BD_ADDR_TYPE_SCO:
6716         case BD_ADDR_TYPE_ACL:
6717             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6718 #endif
6719         default:
6720             return 0;
6721     }
6722 }
6723 
6724 bool gap_bonded(hci_con_handle_t con_handle){
6725 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6726 	if (hci_connection == NULL) return 0;
6727 
6728 #ifdef ENABLE_CLASSIC
6729 	link_key_t link_key;
6730 	link_key_type_t link_key_type;
6731 #endif
6732 	switch (hci_connection->address_type){
6733 #ifdef ENABLE_BLE
6734 		case BD_ADDR_TYPE_LE_PUBLIC:
6735 		case BD_ADDR_TYPE_LE_RANDOM:
6736 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6737 #endif
6738 #ifdef ENABLE_CLASSIC
6739 		case BD_ADDR_TYPE_SCO:
6740 		case BD_ADDR_TYPE_ACL:
6741 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6742 #endif
6743 		default:
6744 			return false;
6745 	}
6746 }
6747 
6748 #ifdef ENABLE_BLE
6749 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6750     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6751     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6752     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6753     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6754     return sm_conn->sm_connection_authorization_state;
6755 }
6756 #endif
6757 
6758 #ifdef ENABLE_CLASSIC
6759 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){
6760     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6761     if (!conn) return GAP_CONNECTION_INVALID;
6762     conn->sniff_min_interval = sniff_min_interval;
6763     conn->sniff_max_interval = sniff_max_interval;
6764     conn->sniff_attempt = sniff_attempt;
6765     conn->sniff_timeout = sniff_timeout;
6766     hci_run();
6767     return 0;
6768 }
6769 
6770 /**
6771  * @brief Exit Sniff mode
6772  * @param con_handle
6773  @ @return 0 if ok
6774  */
6775 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6776     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6777     if (!conn) return GAP_CONNECTION_INVALID;
6778     conn->sniff_min_interval = 0xffff;
6779     hci_run();
6780     return 0;
6781 }
6782 
6783 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){
6784     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6785     if (!conn) return GAP_CONNECTION_INVALID;
6786     conn->sniff_subrating_max_latency = max_latency;
6787     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6788     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6789     hci_run();
6790     return ERROR_CODE_SUCCESS;
6791 }
6792 
6793 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){
6794     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6795     if (!conn) return GAP_CONNECTION_INVALID;
6796     conn->qos_service_type = service_type;
6797     conn->qos_token_rate = token_rate;
6798     conn->qos_peak_bandwidth = peak_bandwidth;
6799     conn->qos_latency = latency;
6800     conn->qos_delay_variation = delay_variation;
6801     hci_run();
6802     return ERROR_CODE_SUCCESS;
6803 }
6804 
6805 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6806     hci_stack->new_page_scan_interval = page_scan_interval;
6807     hci_stack->new_page_scan_window = page_scan_window;
6808     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6809     hci_run();
6810 }
6811 
6812 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6813     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6814     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6815     hci_run();
6816 }
6817 
6818 #endif
6819 
6820 void hci_halting_defer(void){
6821     if (hci_stack->state != HCI_STATE_HALTING) return;
6822     switch (hci_stack->substate){
6823         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6824         case HCI_HALTING_CLOSE:
6825             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6826             break;
6827         default:
6828             break;
6829     }
6830 }
6831 
6832 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6833 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6834     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6835     if (le_device_db_index >= le_device_db_max_count()) return;
6836     uint8_t offset = le_device_db_index >> 3;
6837     uint8_t mask = 1 << (le_device_db_index & 7);
6838     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6839     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6840     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6841         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6842     }
6843 }
6844 
6845 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6846 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6847 	if (le_device_db_index >= le_device_db_max_count()) return;
6848 	uint8_t offset = le_device_db_index >> 3;
6849 	uint8_t mask = 1 << (le_device_db_index & 7);
6850 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6851 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6852 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6853 	}
6854 }
6855 
6856 uint8_t gap_load_resolving_list_from_le_device_db(void){
6857 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6858 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6859 	}
6860 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6861 		// restart le resolving list update
6862 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6863 	}
6864 	return ERROR_CODE_SUCCESS;
6865 }
6866 #endif
6867 
6868 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6869 void hci_setup_test_connections_fuzz(void){
6870     hci_connection_t * conn;
6871 
6872     // default address: 66:55:44:33:00:01
6873     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6874 
6875     // setup Controller info
6876     hci_stack->num_cmd_packets = 255;
6877     hci_stack->acl_packets_total_num = 255;
6878 
6879     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6880     addr[5] = 0x01;
6881     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6882     conn->con_handle = addr[5];
6883     conn->role  = HCI_ROLE_SLAVE;
6884     conn->state = RECEIVED_CONNECTION_REQUEST;
6885     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6886 
6887     // setup incoming Classic SCO connection with con handle 0x0002
6888     addr[5] = 0x02;
6889     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6890     conn->con_handle = addr[5];
6891     conn->role  = HCI_ROLE_SLAVE;
6892     conn->state = RECEIVED_CONNECTION_REQUEST;
6893     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6894 
6895     // setup ready Classic ACL connection with con handle 0x0003
6896     addr[5] = 0x03;
6897     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6898     conn->con_handle = addr[5];
6899     conn->role  = HCI_ROLE_SLAVE;
6900     conn->state = OPEN;
6901     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6902 
6903     // setup ready Classic SCO connection with con handle 0x0004
6904     addr[5] = 0x04;
6905     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6906     conn->con_handle = addr[5];
6907     conn->role  = HCI_ROLE_SLAVE;
6908     conn->state = OPEN;
6909     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6910 
6911     // setup ready LE ACL connection with con handle 0x005 and public address
6912     addr[5] = 0x05;
6913     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6914     conn->con_handle = addr[5];
6915     conn->role  = HCI_ROLE_SLAVE;
6916     conn->state = OPEN;
6917     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6918     conn->sm_connection.sm_connection_encrypted = 1;
6919 }
6920 
6921 void hci_free_connections_fuzz(void){
6922     btstack_linked_list_iterator_t it;
6923     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6924     while (btstack_linked_list_iterator_has_next(&it)){
6925         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6926         btstack_linked_list_iterator_remove(&it);
6927         btstack_memory_hci_connection_free(con);
6928     }
6929 }
6930 void hci_simulate_working_fuzz(void){
6931     hci_init_done();
6932     hci_stack->num_cmd_packets = 255;
6933 }
6934 #endif
6935