xref: /btstack/src/hci.c (revision 35facaddd14848133ea2a677647f4ec949398c6f)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef ENABLE_BLE
57 #include "gap.h"
58 #include "ble/le_device_db.h"
59 #endif
60 
61 #include <stdarg.h>
62 #include <string.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "bluetooth_company_id.h"
70 #include "bluetooth_data_types.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 #include "ad_parser.h"
76 
77 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
78 #ifndef HCI_HOST_ACL_PACKET_NUM
79 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
80 #endif
81 #ifndef HCI_HOST_ACL_PACKET_LEN
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
83 #endif
84 #ifndef HCI_HOST_SCO_PACKET_NUM
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_LEN
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
89 #endif
90 #endif
91 
92 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
93 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
98 #endif
99 
100 #define HCI_CONNECTION_TIMEOUT_MS 10000
101 
102 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
103 #define HCI_RESET_RESEND_TIMEOUT_MS 200
104 #endif
105 
106 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
107 #ifndef GAP_INQUIRY_MAX_NAME_LEN
108 #define GAP_INQUIRY_MAX_NAME_LEN 32
109 #endif
110 
111 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
112 #define GAP_INQUIRY_DURATION_MIN       0x01
113 #define GAP_INQUIRY_DURATION_MAX       0x30
114 #define GAP_INQUIRY_STATE_IDLE         0x00
115 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
116 #define GAP_INQUIRY_STATE_ACTIVE       0x81
117 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
118 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
119 
120 // GAP Remote Name Request
121 #define GAP_REMOTE_NAME_STATE_IDLE 0
122 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
123 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
124 
125 // GAP Pairing
126 #define GAP_PAIRING_STATE_IDLE                       0
127 #define GAP_PAIRING_STATE_SEND_PIN                   1
128 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
129 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
130 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
131 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
132 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
133 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
134 
135 // prototypes
136 #ifdef ENABLE_CLASSIC
137 static void hci_update_scan_enable(void);
138 static void hci_emit_discoverable_enabled(uint8_t enabled);
139 static int  hci_local_ssp_activated(void);
140 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
141 static bool hci_ssp_supported(hci_connection_t * connection);
142 static void hci_notify_if_sco_can_send_now(void);
143 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
144 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
145 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
146 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
147 static void hci_connection_timestamp(hci_connection_t *connection);
148 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
149 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
150 #endif
151 
152 static int  hci_power_control_on(void);
153 static void hci_power_control_off(void);
154 static void hci_state_reset(void);
155 static void hci_emit_transport_packet_sent(void);
156 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
157 static void hci_emit_nr_connections_changed(void);
158 static void hci_emit_hci_open_failed(void);
159 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
160 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
161 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
162 static void hci_run(void);
163 static int  hci_is_le_connection(hci_connection_t * connection);
164 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 #endif
169 
170 #ifdef ENABLE_BLE
171 #ifdef ENABLE_LE_CENTRAL
172 // called from test/ble_client/advertising_data_parser.c
173 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
174 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
175 static hci_connection_t * gap_get_outgoing_connection(void);
176 #endif
177 #endif
178 
179 // the STACK is here
180 #ifndef HAVE_MALLOC
181 static hci_stack_t   hci_stack_static;
182 #endif
183 static hci_stack_t * hci_stack = NULL;
184 
185 #ifdef ENABLE_CLASSIC
186 // default name
187 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
188 
189 // test helper
190 static uint8_t disable_l2cap_timeouts = 0;
191 #endif
192 
193 // reset connection state on create and on reconnect
194 // don't overwrite addr, con handle, role
195 static void hci_connection_init(hci_connection_t * conn){
196     conn->authentication_flags = AUTH_FLAG_NONE;
197     conn->bonding_flags = 0;
198     conn->requested_security_level = LEVEL_0;
199 #ifdef ENABLE_CLASSIC
200     conn->request_role = HCI_ROLE_INVALID;
201     conn->sniff_subrating_max_latency = 0xffff;
202     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
203     conn->link_key_type = INVALID_LINK_KEY;
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219 #ifdef ENABLE_CLASSIC_PAIRING_OOB
220     conn->classic_oob_c_192 = NULL;
221     conn->classic_oob_r_192 = NULL;
222     conn->classic_oob_c_256 = NULL;
223     conn->classic_oob_r_256 = NULL;
224 #endif
225 }
226 
227 /**
228  * create connection for given address
229  *
230  * @return connection OR NULL, if no memory left
231  */
232 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
233     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
234 
235     hci_connection_t * conn = btstack_memory_hci_connection_get();
236     if (!conn) return NULL;
237     hci_connection_init(conn);
238 
239     bd_addr_copy(conn->address, addr);
240     conn->address_type = addr_type;
241     conn->con_handle = HCI_CON_HANDLE_INVALID;
242     conn->role = HCI_ROLE_INVALID;
243 
244     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
245 
246     return conn;
247 }
248 
249 
250 /**
251  * get le connection parameter range
252 *
253  * @return le connection parameter range struct
254  */
255 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
256     *range = hci_stack->le_connection_parameter_range;
257 }
258 
259 /**
260  * set le connection parameter range
261  *
262  */
263 
264 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
265     hci_stack->le_connection_parameter_range = *range;
266 }
267 
268 /**
269  * @brief Test if connection parameters are inside in existing rage
270  * @param conn_interval_min (unit: 1.25ms)
271  * @param conn_interval_max (unit: 1.25ms)
272  * @param conn_latency
273  * @param supervision_timeout (unit: 10ms)
274  * @returns 1 if included
275  */
276 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
277     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
278     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
279 
280     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
281     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
282 
283     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
284     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
285 
286     return 1;
287 }
288 
289 /**
290  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
291  * @note: default: 1
292  * @param max_peripheral_connections
293  */
294 #ifdef ENABLE_LE_PERIPHERAL
295 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
296     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
297 }
298 #endif
299 
300 /**
301  * get hci connections iterator
302  *
303  * @return hci connections iterator
304  */
305 
306 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
307     btstack_linked_list_iterator_init(it, &hci_stack->connections);
308 }
309 
310 /**
311  * get connection for a given handle
312  *
313  * @return connection OR NULL, if not found
314  */
315 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
316     btstack_linked_list_iterator_t it;
317     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
318     while (btstack_linked_list_iterator_has_next(&it)){
319         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
320         if ( item->con_handle == con_handle ) {
321             return item;
322         }
323     }
324     return NULL;
325 }
326 
327 /**
328  * get connection for given address
329  *
330  * @return connection OR NULL, if not found
331  */
332 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != addr_type)  continue;
338         if (memcmp(addr, connection->address, 6) != 0) continue;
339         return connection;
340     }
341     return NULL;
342 }
343 
344 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
345     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
346 }
347 
348 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
349     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
350 }
351 
352 #ifdef ENABLE_CLASSIC
353 
354 #ifdef ENABLE_SCO_OVER_HCI
355 static int hci_number_sco_connections(void){
356     int connections = 0;
357     btstack_linked_list_iterator_t it;
358     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
359     while (btstack_linked_list_iterator_has_next(&it)){
360         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
361         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
362         connections++;
363     }
364     return connections;
365 }
366 #endif
367 
368 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
369     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
370 #ifdef HAVE_EMBEDDED_TICK
371     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
372         // connections might be timed out
373         hci_emit_l2cap_check_timeout(connection);
374     }
375 #else
376     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
377         // connections might be timed out
378         hci_emit_l2cap_check_timeout(connection);
379     }
380 #endif
381 }
382 
383 static void hci_connection_timestamp(hci_connection_t *connection){
384 #ifdef HAVE_EMBEDDED_TICK
385     connection->timestamp = btstack_run_loop_embedded_get_ticks();
386 #else
387     connection->timestamp = btstack_run_loop_get_time_ms();
388 #endif
389 }
390 
391 /**
392  * add authentication flags and reset timer
393  * @note: assumes classic connection
394  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
395  */
396 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
397     bd_addr_t addr;
398     reverse_bd_addr(bd_addr, addr);
399     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
400     if (conn) {
401         connectionSetAuthenticationFlags(conn, flags);
402         hci_connection_timestamp(conn);
403     }
404 }
405 
406 static bool hci_pairing_active(hci_connection_t * hci_connection){
407     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
408 }
409 
410 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
411     if (hci_pairing_active(hci_connection)) return;
412     if (ssp){
413         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
414     } else {
415         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
416     }
417     // if we are initiator, we have sent an HCI Authenticate Request
418     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
419 
420     // if we are responder, use minimal service security level as required level
421     if (!initiator){
422         hci_connection->requested_security_level = (gap_security_level_t) btstack_max((uint32_t) hci_connection->requested_security_level, (uint32_t) hci_stack->gap_minimal_service_security_level);
423     }
424 
425     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
426 
427     uint8_t event[12];
428     event[0] = GAP_EVENT_PAIRING_STARTED;
429     event[1] = 10;
430     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
431     reverse_bd_addr(hci_connection->address, &event[4]);
432     event[10] = (uint8_t) ssp;
433     event[11] = (uint8_t) initiator;
434     hci_emit_event(event, sizeof(event), 1);
435 }
436 
437 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
438     hci_connection->requested_security_level = LEVEL_0;
439     if (!hci_pairing_active(hci_connection)) return;
440     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
441 #ifdef ENABLE_CLASSIC_PAIRING_OOB
442     hci_connection->classic_oob_c_192 = NULL;
443     hci_connection->classic_oob_r_192 = NULL;
444     hci_connection->classic_oob_c_256 = NULL;
445     hci_connection->classic_oob_r_256 = NULL;
446 #endif
447     log_info("pairing complete, status %02x", status);
448 
449     uint8_t event[12];
450     event[0] = GAP_EVENT_PAIRING_COMPLETE;
451     event[1] = 9;
452     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
453     reverse_bd_addr(hci_connection->address, &event[4]);
454     event[10] = status;
455     hci_emit_event(event, sizeof(event), 1);
456 }
457 
458 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
459     hci_connection_t * conn = hci_connection_for_handle(handle);
460     if (!conn) return false;
461     return hci_pairing_active(conn);
462 }
463 
464 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
465     if (!hci_stack->link_key_db) return;
466     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
467     hci_stack->link_key_db->delete_link_key(addr);
468 }
469 
470 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
471     if (!hci_stack->link_key_db) return;
472     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
473     hci_stack->link_key_db->put_link_key(addr, link_key, type);
474 }
475 
476 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
477 	if (!hci_stack->link_key_db) return false;
478 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
479 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
480 	return result;
481 }
482 
483 void gap_delete_all_link_keys(void){
484     bd_addr_t  addr;
485     link_key_t link_key;
486     link_key_type_t type;
487     btstack_link_key_iterator_t it;
488     int ok = gap_link_key_iterator_init(&it);
489     if (!ok) {
490         log_error("could not initialize iterator");
491         return;
492     }
493     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
494         gap_drop_link_key_for_bd_addr(addr);
495     }
496     gap_link_key_iterator_done(&it);
497 }
498 
499 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
500     if (!hci_stack->link_key_db) return 0;
501     if (!hci_stack->link_key_db->iterator_init) return 0;
502     return hci_stack->link_key_db->iterator_init(it);
503 }
504 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
505     if (!hci_stack->link_key_db) return 0;
506     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
507 }
508 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
509     if (!hci_stack->link_key_db) return;
510     hci_stack->link_key_db->iterator_done(it);
511 }
512 #endif
513 
514 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
515     switch (address_type){
516         case BD_ADDR_TYPE_LE_PUBLIC:
517         case BD_ADDR_TYPE_LE_RANDOM:
518         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
519         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
520             return true;
521         default:
522             return false;
523     }
524 }
525 
526 static int hci_is_le_connection(hci_connection_t * connection){
527     return hci_is_le_connection_type(connection->address_type);
528 }
529 
530 /**
531  * count connections
532  */
533 static int nr_hci_connections(void){
534     int count = 0;
535     btstack_linked_item_t *it;
536     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
537         count++;
538     }
539     return count;
540 }
541 
542 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
543 
544     unsigned int num_packets_sent_classic = 0;
545     unsigned int num_packets_sent_le = 0;
546 
547     btstack_linked_item_t *it;
548     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
549         hci_connection_t * connection = (hci_connection_t *) it;
550         if (hci_is_le_connection(connection)){
551             num_packets_sent_le += connection->num_packets_sent;
552         }
553         if (connection->address_type == BD_ADDR_TYPE_ACL){
554             num_packets_sent_classic += connection->num_packets_sent;
555         }
556     }
557     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
558     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
559     int free_slots_le = 0;
560 
561     if (free_slots_classic < 0){
562         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
563         return 0;
564     }
565 
566     if (hci_stack->le_acl_packets_total_num){
567         // if we have LE slots, they are used
568         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
569         if (free_slots_le < 0){
570             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
571             return 0;
572         }
573     } else {
574         // otherwise, classic slots are used for LE, too
575         free_slots_classic -= num_packets_sent_le;
576         if (free_slots_classic < 0){
577             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
578             return 0;
579         }
580     }
581 
582     switch (address_type){
583         case BD_ADDR_TYPE_UNKNOWN:
584             log_error("hci_number_free_acl_slots: unknown address type");
585             return 0;
586 
587         case BD_ADDR_TYPE_ACL:
588             return free_slots_classic;
589 
590         default:
591            if (hci_stack->le_acl_packets_total_num){
592                return free_slots_le;
593            }
594            return free_slots_classic;
595     }
596 }
597 
598 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
599     // get connection type
600     hci_connection_t * connection = hci_connection_for_handle(con_handle);
601     if (!connection){
602         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
603         return 0;
604     }
605     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
606 }
607 
608 #ifdef ENABLE_CLASSIC
609 static int hci_number_free_sco_slots(void){
610     unsigned int num_sco_packets_sent  = 0;
611     btstack_linked_item_t *it;
612     if (hci_stack->synchronous_flow_control_enabled){
613         // explicit flow control
614         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
615             hci_connection_t * connection = (hci_connection_t *) it;
616             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
617             num_sco_packets_sent += connection->num_packets_sent;
618         }
619         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
620             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
621             return 0;
622         }
623         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
624     } else {
625         // implicit flow control -- TODO
626         int num_ready = 0;
627         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
628             hci_connection_t * connection = (hci_connection_t *) it;
629             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
630             if (connection->sco_tx_ready == 0) continue;
631             num_ready++;
632         }
633         return num_ready;
634     }
635 }
636 #endif
637 
638 // only used to send HCI Host Number Completed Packets
639 static int hci_can_send_comand_packet_transport(void){
640     if (hci_stack->hci_packet_buffer_reserved) return 0;
641 
642     // check for async hci transport implementations
643     if (hci_stack->hci_transport->can_send_packet_now){
644         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
645             return 0;
646         }
647     }
648     return 1;
649 }
650 
651 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
652 bool hci_can_send_command_packet_now(void){
653     if (hci_can_send_comand_packet_transport() == 0) return false;
654     return hci_stack->num_cmd_packets > 0u;
655 }
656 
657 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
658     // check for async hci transport implementations
659     if (!hci_stack->hci_transport->can_send_packet_now) return true;
660     return hci_stack->hci_transport->can_send_packet_now(packet_type);
661 }
662 
663 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
664     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
665     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
666 }
667 
668 bool hci_can_send_acl_le_packet_now(void){
669     if (hci_stack->hci_packet_buffer_reserved) return false;
670     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
671 }
672 
673 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
674     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
675     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
676 }
677 
678 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
679     if (hci_stack->hci_packet_buffer_reserved) return false;
680     return hci_can_send_prepared_acl_packet_now(con_handle);
681 }
682 
683 #ifdef ENABLE_CLASSIC
684 bool hci_can_send_acl_classic_packet_now(void){
685     if (hci_stack->hci_packet_buffer_reserved) return false;
686     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
687 }
688 
689 bool hci_can_send_prepared_sco_packet_now(void){
690     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
691     if (hci_have_usb_transport()){
692         return hci_stack->sco_can_send_now;
693     } else {
694         return hci_number_free_sco_slots() > 0;
695     }
696 }
697 
698 bool hci_can_send_sco_packet_now(void){
699     if (hci_stack->hci_packet_buffer_reserved) return false;
700     return hci_can_send_prepared_sco_packet_now();
701 }
702 
703 void hci_request_sco_can_send_now_event(void){
704     hci_stack->sco_waiting_for_can_send_now = 1;
705     hci_notify_if_sco_can_send_now();
706 }
707 #endif
708 
709 // used for internal checks in l2cap.c
710 bool hci_is_packet_buffer_reserved(void){
711     return hci_stack->hci_packet_buffer_reserved;
712 }
713 
714 // reserves outgoing packet buffer. @returns 1 if successful
715 bool hci_reserve_packet_buffer(void){
716     if (hci_stack->hci_packet_buffer_reserved) {
717         log_error("hci_reserve_packet_buffer called but buffer already reserved");
718         return false;
719     }
720     hci_stack->hci_packet_buffer_reserved = true;
721     return true;
722 }
723 
724 void hci_release_packet_buffer(void){
725     hci_stack->hci_packet_buffer_reserved = false;
726 }
727 
728 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
729 static int hci_transport_synchronous(void){
730     return hci_stack->hci_transport->can_send_packet_now == NULL;
731 }
732 
733 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
734 
735     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
736 
737     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
738     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
739     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
740         max_acl_data_packet_length = hci_stack->le_data_packets_length;
741     }
742 
743 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
744     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
745         max_acl_data_packet_length = connection->le_max_tx_octets;
746     }
747 #endif
748 
749     log_debug("hci_send_acl_packet_fragments entered");
750 
751     uint8_t status = ERROR_CODE_SUCCESS;
752     // multiple packets could be send on a synchronous HCI transport
753     while (true){
754 
755         log_debug("hci_send_acl_packet_fragments loop entered");
756 
757         // get current data
758         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
759         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
760         bool more_fragments = false;
761 
762         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
763         if (current_acl_data_packet_length > max_acl_data_packet_length){
764             more_fragments = true;
765             current_acl_data_packet_length = max_acl_data_packet_length;
766         }
767 
768         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
769         if (acl_header_pos > 0u){
770             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
771             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
772             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
773         }
774 
775         // update header len
776         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
777 
778         // count packet
779         connection->num_packets_sent++;
780         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
781 
782         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
783         if (more_fragments){
784             // update start of next fragment to send
785             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
786         } else {
787             // done
788             hci_stack->acl_fragmentation_pos = 0;
789             hci_stack->acl_fragmentation_total_size = 0;
790         }
791 
792         // send packet
793         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
794         const int size = current_acl_data_packet_length + 4;
795         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
796         hci_stack->acl_fragmentation_tx_active = 1;
797         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
798         if (err != 0){
799             // no error from HCI Transport expected
800             status = ERROR_CODE_HARDWARE_FAILURE;
801         }
802 
803         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
804 
805         // done yet?
806         if (!more_fragments) break;
807 
808         // can send more?
809         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
810     }
811 
812     log_debug("hci_send_acl_packet_fragments loop over");
813 
814     // release buffer now for synchronous transport
815     if (hci_transport_synchronous()){
816         hci_stack->acl_fragmentation_tx_active = 0;
817         hci_release_packet_buffer();
818         hci_emit_transport_packet_sent();
819     }
820 
821     return status;
822 }
823 
824 // pre: caller has reserved the packet buffer
825 uint8_t hci_send_acl_packet_buffer(int size){
826     btstack_assert(hci_stack->hci_packet_buffer_reserved);
827 
828     uint8_t * packet = hci_stack->hci_packet_buffer;
829     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
830 
831     // check for free places on Bluetooth module
832     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
833         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
834         hci_release_packet_buffer();
835         hci_emit_transport_packet_sent();
836         return BTSTACK_ACL_BUFFERS_FULL;
837     }
838 
839     hci_connection_t *connection = hci_connection_for_handle( con_handle);
840     if (!connection) {
841         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
842         hci_release_packet_buffer();
843         hci_emit_transport_packet_sent();
844         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
845     }
846 
847 #ifdef ENABLE_CLASSIC
848     hci_connection_timestamp(connection);
849 #endif
850 
851     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
852 
853     // setup data
854     hci_stack->acl_fragmentation_total_size = size;
855     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
856 
857     return hci_send_acl_packet_fragments(connection);
858 }
859 
860 #ifdef ENABLE_CLASSIC
861 // pre: caller has reserved the packet buffer
862 uint8_t hci_send_sco_packet_buffer(int size){
863     btstack_assert(hci_stack->hci_packet_buffer_reserved);
864 
865     uint8_t * packet = hci_stack->hci_packet_buffer;
866 
867     // skip checks in loopback mode
868     if (!hci_stack->loopback_mode){
869         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
870 
871         // check for free places on Bluetooth module
872         if (!hci_can_send_prepared_sco_packet_now()) {
873             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
874             hci_release_packet_buffer();
875             hci_emit_transport_packet_sent();
876             return BTSTACK_ACL_BUFFERS_FULL;
877         }
878 
879         // track send packet in connection struct
880         hci_connection_t *connection = hci_connection_for_handle( con_handle);
881         if (!connection) {
882             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
883             hci_release_packet_buffer();
884             hci_emit_transport_packet_sent();
885             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
886         }
887 
888         if (hci_have_usb_transport()){
889             // token used
890             hci_stack->sco_can_send_now = false;
891         } else {
892             if (hci_stack->synchronous_flow_control_enabled){
893                 connection->num_packets_sent++;
894             } else {
895                 connection->sco_tx_ready--;
896             }
897         }
898     }
899 
900     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
901 
902 #ifdef HAVE_SCO_TRANSPORT
903     hci_stack->sco_transport->send_packet(packet, size);
904     hci_release_packet_buffer();
905     hci_emit_transport_packet_sent();
906 
907     return 0;
908 #else
909     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
910     if (hci_transport_synchronous()){
911         hci_release_packet_buffer();
912         hci_emit_transport_packet_sent();
913     }
914 
915     if (err != 0){
916         return ERROR_CODE_HARDWARE_FAILURE;
917     }
918     return ERROR_CODE_SUCCESS;
919 #endif
920 }
921 #endif
922 
923 static void acl_handler(uint8_t *packet, uint16_t size){
924 
925     // get info
926     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
927     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
928     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
929     uint16_t acl_length         = READ_ACL_LENGTH(packet);
930 
931     // ignore non-registered handle
932     if (!conn){
933         log_error("acl_handler called with non-registered handle %u!" , con_handle);
934         return;
935     }
936 
937     // assert packet is complete
938     if ((acl_length + 4u) != size){
939         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
940         return;
941     }
942 
943 #ifdef ENABLE_CLASSIC
944     // update idle timestamp
945     hci_connection_timestamp(conn);
946 #endif
947 
948 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
949     hci_stack->host_completed_packets = 1;
950     conn->num_packets_completed++;
951 #endif
952 
953     // handle different packet types
954     switch (acl_flags & 0x03u) {
955 
956         case 0x01: // continuation fragment
957 
958             // sanity checks
959             if (conn->acl_recombination_pos == 0u) {
960                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
961                 return;
962             }
963             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
964                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
965                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
966                 conn->acl_recombination_pos = 0;
967                 return;
968             }
969 
970             // append fragment payload (header already stored)
971             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
972                          &packet[4], acl_length);
973             conn->acl_recombination_pos += acl_length;
974 
975             // forward complete L2CAP packet if complete.
976             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
977                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
978                 // reset recombination buffer
979                 conn->acl_recombination_length = 0;
980                 conn->acl_recombination_pos = 0;
981             }
982             break;
983 
984         case 0x02: { // first fragment
985 
986             // sanity check
987             if (conn->acl_recombination_pos) {
988                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
989                 conn->acl_recombination_pos = 0;
990             }
991 
992             // peek into L2CAP packet!
993             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
994 
995             // compare fragment size to L2CAP packet size
996             if (acl_length >= (l2cap_length + 4u)){
997                 // forward fragment as L2CAP packet
998                 hci_emit_acl_packet(packet, acl_length + 4u);
999             } else {
1000 
1001                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1002                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1003                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1004                     return;
1005                 }
1006 
1007                 // store first fragment and tweak acl length for complete package
1008                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1009                              packet, acl_length + 4u);
1010                 conn->acl_recombination_pos    = acl_length + 4u;
1011                 conn->acl_recombination_length = l2cap_length;
1012                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1013             }
1014             break;
1015 
1016         }
1017         default:
1018             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1019             return;
1020     }
1021 
1022     // execute main loop
1023     hci_run();
1024 }
1025 
1026 static void hci_connection_stop_timer(hci_connection_t * conn){
1027     btstack_run_loop_remove_timer(&conn->timeout);
1028 #ifdef ENABLE_CLASSIC
1029     btstack_run_loop_remove_timer(&conn->timeout_sco);
1030 #endif
1031 }
1032 
1033 static void hci_shutdown_connection(hci_connection_t *conn){
1034     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1035 
1036 #ifdef ENABLE_CLASSIC
1037 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1038     bd_addr_type_t addr_type = conn->address_type;
1039 #endif
1040 #ifdef HAVE_SCO_TRANSPORT
1041     hci_con_handle_t con_handle = conn->con_handle;
1042 #endif
1043 #endif
1044 
1045     hci_connection_stop_timer(conn);
1046 
1047     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1048     btstack_memory_hci_connection_free( conn );
1049 
1050     // now it's gone
1051     hci_emit_nr_connections_changed();
1052 
1053 #ifdef ENABLE_CLASSIC
1054 #ifdef ENABLE_SCO_OVER_HCI
1055     // update SCO
1056     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1057         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1058     }
1059 #endif
1060 #ifdef HAVE_SCO_TRANSPORT
1061     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1062         hci_stack->sco_transport->close(con_handle);
1063     }
1064 #endif
1065 #endif
1066 }
1067 
1068 #ifdef ENABLE_CLASSIC
1069 
1070 static const uint16_t packet_type_sizes[] = {
1071     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1072     HCI_ACL_DH1_SIZE, 0, 0, 0,
1073     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1074     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1075 };
1076 static const uint8_t  packet_type_feature_requirement_bit[] = {
1077      0, // 3 slot packets
1078      1, // 5 slot packets
1079     25, // EDR 2 mpbs
1080     26, // EDR 3 mbps
1081     39, // 3 slot EDR packts
1082     40, // 5 slot EDR packet
1083 };
1084 static const uint16_t packet_type_feature_packet_mask[] = {
1085     0x0f00, // 3 slot packets
1086     0xf000, // 5 slot packets
1087     0x1102, // EDR 2 mpbs
1088     0x2204, // EDR 3 mbps
1089     0x0300, // 3 slot EDR packts
1090     0x3000, // 5 slot EDR packet
1091 };
1092 
1093 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1094     // enable packet types based on size
1095     uint16_t packet_types = 0;
1096     unsigned int i;
1097     for (i=0;i<16;i++){
1098         if (packet_type_sizes[i] == 0) continue;
1099         if (packet_type_sizes[i] <= buffer_size){
1100             packet_types |= 1 << i;
1101         }
1102     }
1103     // disable packet types due to missing local supported features
1104     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1105         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1106         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1107         if (feature_set) continue;
1108         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1109         packet_types &= ~packet_type_feature_packet_mask[i];
1110     }
1111     // flip bits for "may not be used"
1112     packet_types ^= 0x3306;
1113     return packet_types;
1114 }
1115 
1116 uint16_t hci_usable_acl_packet_types(void){
1117     return hci_stack->packet_types;
1118 }
1119 #endif
1120 
1121 uint8_t* hci_get_outgoing_packet_buffer(void){
1122     // hci packet buffer is >= acl data packet length
1123     return hci_stack->hci_packet_buffer;
1124 }
1125 
1126 uint16_t hci_max_acl_data_packet_length(void){
1127     return hci_stack->acl_data_packet_length;
1128 }
1129 
1130 #ifdef ENABLE_CLASSIC
1131 bool hci_extended_sco_link_supported(void){
1132     // No. 31, byte 3, bit 7
1133     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1134 }
1135 #endif
1136 
1137 bool hci_non_flushable_packet_boundary_flag_supported(void){
1138     // No. 54, byte 6, bit 6
1139     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1140 }
1141 
1142 static int gap_ssp_supported(void){
1143     // No. 51, byte 6, bit 3
1144     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1145 }
1146 
1147 static int hci_classic_supported(void){
1148 #ifdef ENABLE_CLASSIC
1149     // No. 37, byte 4, bit 5, = No BR/EDR Support
1150     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1151 #else
1152     return 0;
1153 #endif
1154 }
1155 
1156 static int hci_le_supported(void){
1157 #ifdef ENABLE_BLE
1158     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1159     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1160 #else
1161     return 0;
1162 #endif
1163 }
1164 
1165 #ifdef ENABLE_BLE
1166 
1167 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1168     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1169         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1170     } else {
1171         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1172     }
1173 }
1174 
1175 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1176     *addr_type = hci_stack->le_own_addr_type;
1177     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1178 }
1179 
1180 #ifdef ENABLE_LE_PERIPHERAL
1181 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1182     *addr_type = hci_stack->le_advertisements_own_addr_type;
1183     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1184 };
1185 #endif
1186 
1187 #ifdef ENABLE_LE_CENTRAL
1188 
1189 /**
1190  * @brief Get own addr type and address used for LE connections (Central)
1191  */
1192 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1193     *addr_type = hci_stack->le_connection_own_addr_type;
1194     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1195 }
1196 
1197 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1198 
1199     int offset = 3;
1200     int num_reports = packet[offset];
1201     offset += 1;
1202 
1203     int i;
1204     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1205     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1206     for (i=0; (i<num_reports) && (offset < size);i++){
1207         // sanity checks on data_length:
1208         uint8_t data_length = packet[offset + 8];
1209         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1210         if ((offset + 9u + data_length + 1u) > size)    return;
1211         // setup event
1212         uint8_t event_size = 10u + data_length;
1213         int pos = 0;
1214         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1215         event[pos++] = event_size;
1216         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1217         offset += 8;
1218         pos += 8;
1219         event[pos++] = packet[offset + 1 + data_length]; // rssi
1220         event[pos++] = data_length;
1221         offset++;
1222         (void)memcpy(&event[pos], &packet[offset], data_length);
1223         pos +=    data_length;
1224         offset += data_length + 1u; // rssi
1225         hci_emit_event(event, pos, 1);
1226     }
1227 }
1228 #endif
1229 #endif
1230 
1231 #ifdef ENABLE_BLE
1232 #ifdef ENABLE_LE_PERIPHERAL
1233 static void hci_update_advertisements_enabled_for_current_roles(void){
1234     if (hci_stack->le_advertisements_enabled){
1235         // get number of active le slave connections
1236         int num_slave_connections = 0;
1237         btstack_linked_list_iterator_t it;
1238         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1239         while (btstack_linked_list_iterator_has_next(&it)){
1240             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1241             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1242             if (con->state != OPEN) continue;
1243             if (con->role  != HCI_ROLE_SLAVE) continue;
1244             if (!hci_is_le_connection(con)) continue;
1245             num_slave_connections++;
1246         }
1247         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1248         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1249     } else {
1250         hci_stack->le_advertisements_enabled_for_current_roles = false;
1251     }
1252 }
1253 #endif
1254 #endif
1255 
1256 #ifdef ENABLE_CLASSIC
1257 static void gap_run_set_local_name(void){
1258     hci_reserve_packet_buffer();
1259     uint8_t * packet = hci_stack->hci_packet_buffer;
1260     // construct HCI Command and send
1261     uint16_t opcode = hci_write_local_name.opcode;
1262     hci_stack->last_cmd_opcode = opcode;
1263     packet[0] = opcode & 0xff;
1264     packet[1] = opcode >> 8;
1265     packet[2] = DEVICE_NAME_LEN;
1266     memset(&packet[3], 0, DEVICE_NAME_LEN);
1267     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1268     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1269     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1270     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1271     // expand '00:00:00:00:00:00' in name with bd_addr
1272     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1273     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1274 }
1275 
1276 static void gap_run_set_eir_data(void){
1277     hci_reserve_packet_buffer();
1278     uint8_t * packet = hci_stack->hci_packet_buffer;
1279     // construct HCI Command in-place and send
1280     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1281     hci_stack->last_cmd_opcode = opcode;
1282     uint16_t offset = 0;
1283     packet[offset++] = opcode & 0xff;
1284     packet[offset++] = opcode >> 8;
1285     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1286     packet[offset++] = 0;  // FEC not required
1287     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1288     if (hci_stack->eir_data){
1289         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1290         ad_context_t context;
1291         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1292             uint8_t data_type   = ad_iterator_get_data_type(&context);
1293             uint8_t size        = ad_iterator_get_data_len(&context);
1294             const uint8_t *data = ad_iterator_get_data(&context);
1295             // copy item
1296             packet[offset++] = size + 1;
1297             packet[offset++] = data_type;
1298             memcpy(&packet[offset], data, size);
1299             // update name item
1300             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1301                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1302             }
1303             offset += size;
1304         }
1305     } else {
1306         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1307         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1308         packet[offset++] = bytes_to_copy + 1;
1309         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1310         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1311         // expand '00:00:00:00:00:00' in name with bd_addr
1312         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1313     }
1314     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1315 }
1316 
1317 static void hci_run_gap_tasks_classic(void){
1318     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1319         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1320         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1321         return;
1322     }
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1325         gap_run_set_local_name();
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1330         gap_run_set_eir_data();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1335         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1336         return;
1337     }
1338     // write page scan activity
1339     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1340         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1341         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1342         return;
1343     }
1344     // write page scan type
1345     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1346         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1347         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1348         return;
1349     }
1350     // send scan enable
1351     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1352         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1353         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1354         return;
1355     }
1356 }
1357 #endif
1358 
1359 #ifndef HAVE_HOST_CONTROLLER_API
1360 
1361 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1362     if (!hci_stack->config) return 0;
1363     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1364     // Limit baud rate for Broadcom chipsets to 3 mbps
1365     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1366         baud_rate = 3000000;
1367     }
1368     return baud_rate;
1369 }
1370 
1371 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1372     UNUSED(ds);
1373 
1374     switch (hci_stack->substate){
1375         case HCI_INIT_W4_SEND_RESET:
1376             log_info("Resend HCI Reset");
1377             hci_stack->substate = HCI_INIT_SEND_RESET;
1378             hci_stack->num_cmd_packets = 1;
1379             hci_run();
1380             break;
1381         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1382             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1383             if (hci_stack->hci_transport->reset_link){
1384                 hci_stack->hci_transport->reset_link();
1385             }
1386 
1387             /* fall through */
1388 
1389         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1390             log_info("Resend HCI Reset - CSR Warm Boot");
1391             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1392             hci_stack->num_cmd_packets = 1;
1393             hci_run();
1394             break;
1395         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1396             if (hci_stack->hci_transport->set_baudrate){
1397                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1398                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1399                 hci_stack->hci_transport->set_baudrate(baud_rate);
1400             }
1401             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1402             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1403                 if (hci_stack->hci_transport->reset_link){
1404                     log_info("Link Reset");
1405                     hci_stack->hci_transport->reset_link();
1406                 }
1407                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1408                 hci_run();
1409             }
1410             break;
1411         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1412             // otherwise continue
1413             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1414             hci_send_cmd(&hci_read_local_supported_commands);
1415             break;
1416         default:
1417             break;
1418     }
1419 }
1420 #endif
1421 
1422 static void hci_initializing_next_state(void){
1423     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1424 }
1425 
1426 // assumption: hci_can_send_command_packet_now() == true
1427 static void hci_initializing_run(void){
1428     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1429     switch (hci_stack->substate){
1430         case HCI_INIT_SEND_RESET:
1431             hci_state_reset();
1432 
1433 #ifndef HAVE_HOST_CONTROLLER_API
1434             // prepare reset if command complete not received in 100ms
1435             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1436             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1437             btstack_run_loop_add_timer(&hci_stack->timeout);
1438 #endif
1439             // send command
1440             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1441             hci_send_cmd(&hci_reset);
1442             break;
1443         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1444             hci_send_cmd(&hci_read_local_version_information);
1445             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1446             break;
1447         case HCI_INIT_SEND_READ_LOCAL_NAME:
1448             hci_send_cmd(&hci_read_local_name);
1449             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1450             break;
1451 
1452 #ifndef HAVE_HOST_CONTROLLER_API
1453         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1454             hci_state_reset();
1455             // prepare reset if command complete not received in 100ms
1456             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1457             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1458             btstack_run_loop_add_timer(&hci_stack->timeout);
1459             // send command
1460             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1461             hci_send_cmd(&hci_reset);
1462             break;
1463         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1464             hci_state_reset();
1465             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1466             hci_send_cmd(&hci_reset);
1467             break;
1468         case HCI_INIT_SEND_BAUD_CHANGE: {
1469             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1470             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1471             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1472             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1473             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1474             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1475             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1476             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1477                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1478                 btstack_run_loop_add_timer(&hci_stack->timeout);
1479             }
1480             break;
1481         }
1482         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1483             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1484             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1485             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1486             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1487             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1488             break;
1489         }
1490         case HCI_INIT_CUSTOM_INIT:
1491             // Custom initialization
1492             if (hci_stack->chipset && hci_stack->chipset->next_command){
1493                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1494                 bool send_cmd = false;
1495                 switch (hci_stack->chipset_result){
1496                     case BTSTACK_CHIPSET_VALID_COMMAND:
1497                         send_cmd = true;
1498                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1499                         break;
1500                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1501                         send_cmd = true;
1502                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1503                         log_info("CSR Warm Boot");
1504                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1505                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1506                         btstack_run_loop_add_timer(&hci_stack->timeout);
1507                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1508                             && hci_stack->config
1509                             && hci_stack->chipset
1510                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1511                             && hci_stack->hci_transport->set_baudrate
1512                             && hci_transport_uart_get_main_baud_rate()){
1513                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1514                         } else {
1515                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1516                         }
1517                         break;
1518                     default:
1519                         break;
1520                 }
1521 
1522                 if (send_cmd){
1523                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1524                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1525                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1526                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1527                     break;
1528                 }
1529                 log_info("Init script done");
1530 
1531                 // Init script download on Broadcom chipsets causes:
1532                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1533                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1534                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1535 
1536                     // - baud rate to reset, restore UART baud rate if needed
1537                     int need_baud_change = hci_stack->config
1538                         && hci_stack->chipset
1539                         && hci_stack->chipset->set_baudrate_command
1540                         && hci_stack->hci_transport->set_baudrate
1541                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1542                     if (need_baud_change) {
1543                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1544                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1545                         hci_stack->hci_transport->set_baudrate(baud_rate);
1546                     }
1547 
1548                     uint16_t bcm_delay_ms = 300;
1549                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1550                     //   -> Work around: wait here.
1551                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1552                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1553                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1554                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1555                     btstack_run_loop_add_timer(&hci_stack->timeout);
1556                     break;
1557                 }
1558             }
1559             // otherwise continue
1560             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1561             hci_send_cmd(&hci_read_local_supported_commands);
1562             break;
1563         case HCI_INIT_SET_BD_ADDR:
1564             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1565             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1566             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1567             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1568             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1569             break;
1570 #endif
1571 
1572         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1573             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1574             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1575             hci_send_cmd(&hci_read_local_supported_commands);
1576             break;
1577         case HCI_INIT_READ_BD_ADDR:
1578             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1579             hci_send_cmd(&hci_read_bd_addr);
1580             break;
1581         case HCI_INIT_READ_BUFFER_SIZE:
1582             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1583             hci_send_cmd(&hci_read_buffer_size);
1584             break;
1585         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1586             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1587             hci_send_cmd(&hci_read_local_supported_features);
1588             break;
1589 
1590 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1591         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1592             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1593             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1594             break;
1595         case HCI_INIT_HOST_BUFFER_SIZE:
1596             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1597             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1598                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1599             break;
1600 #endif
1601 
1602         case HCI_INIT_SET_EVENT_MASK:
1603             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1604             if (hci_le_supported()){
1605                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1606             } else {
1607                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1608                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1609             }
1610             break;
1611 
1612 #ifdef ENABLE_CLASSIC
1613         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1614             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1615             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1616             break;
1617         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1618             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1619             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1620             break;
1621         case HCI_INIT_WRITE_INQUIRY_MODE:
1622             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1623             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1624             break;
1625         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1626             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1627 			hci_stack->secure_connections_active = true;
1628             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1629             break;
1630         // only sent if ENABLE_SCO_OVER_HCI is defined
1631         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1632             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1633             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1634             break;
1635         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1636             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1637             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1638             break;
1639         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1640         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1641             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1642 #ifdef ENABLE_SCO_OVER_HCI
1643             log_info("BCM: Route SCO data via HCI transport");
1644             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1645 #endif
1646 #ifdef ENABLE_SCO_OVER_PCM
1647             log_info("BCM: Route SCO data via PCM interface");
1648 #ifdef ENABLE_BCM_PCM_WBS
1649             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1650             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1651 #else
1652             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1653             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1654 #endif
1655 #endif
1656             break;
1657 #ifdef ENABLE_SCO_OVER_PCM
1658         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1659             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1660             log_info("BCM: Config PCM interface for I2S");
1661 #ifdef ENABLE_BCM_PCM_WBS
1662             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1663             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1664 #else
1665             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1666             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1667 #endif
1668             break;
1669 #endif
1670 #endif
1671 
1672 #ifdef ENABLE_BLE
1673         // LE INIT
1674         case HCI_INIT_LE_READ_BUFFER_SIZE:
1675             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1676             hci_send_cmd(&hci_le_read_buffer_size);
1677             break;
1678         case HCI_INIT_LE_SET_EVENT_MASK:
1679             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1680             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1681             break;
1682         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1683             // LE Supported Host = 1, Simultaneous Host = 0
1684             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1685             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1686             break;
1687 #endif
1688 
1689 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1690         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1691             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1692             hci_send_cmd(&hci_le_read_maximum_data_length);
1693             break;
1694         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1695             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1696             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1697             break;
1698 #endif
1699 
1700 #ifdef ENABLE_LE_CENTRAL
1701         case HCI_INIT_READ_WHITE_LIST_SIZE:
1702             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1703             hci_send_cmd(&hci_le_read_white_list_size);
1704             break;
1705         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1706             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1707             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);
1708             break;
1709 #endif
1710         default:
1711             return;
1712     }
1713 }
1714 
1715 static void hci_init_done(void){
1716 #ifdef ENABLE_CLASSIC
1717     // init sequence complete, check if GAP Tasks are completed
1718     if (hci_stack->gap_tasks != 0) {
1719         hci_run_gap_tasks_classic();
1720         return;
1721     }
1722 #endif
1723 
1724     // done. tell the app
1725     log_info("hci_init_done -> HCI_STATE_WORKING");
1726     hci_stack->state = HCI_STATE_WORKING;
1727     hci_emit_state();
1728     hci_run();
1729 }
1730 
1731 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1732     bool command_completed = false;
1733     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1734         uint16_t opcode = little_endian_read_16(packet,3);
1735         if (opcode == hci_stack->last_cmd_opcode){
1736             command_completed = true;
1737             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1738         } else {
1739             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1740         }
1741     }
1742 
1743     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1744         uint8_t  status = packet[2];
1745         uint16_t opcode = little_endian_read_16(packet,4);
1746         if (opcode == hci_stack->last_cmd_opcode){
1747             if (status){
1748                 command_completed = true;
1749                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1750             } else {
1751                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1752             }
1753         } else {
1754             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1755         }
1756     }
1757 #ifndef HAVE_HOST_CONTROLLER_API
1758     // Vendor == CSR
1759     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1760         // TODO: track actual command
1761         command_completed = true;
1762     }
1763 
1764     // Vendor == Toshiba
1765     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1766         // TODO: track actual command
1767         command_completed = true;
1768         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1769         hci_stack->num_cmd_packets = 1;
1770     }
1771 #endif
1772 
1773     return command_completed;
1774 }
1775 
1776 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1777 
1778     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1779 
1780     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1781 
1782 #ifndef HAVE_HOST_CONTROLLER_API
1783 
1784     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1785     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1786     //
1787     // HCI Reset
1788     // Timeout 100 ms
1789     // HCI Reset
1790     // Command Complete Reset
1791     // HCI Read Local Version Information
1792     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1793     // hang...
1794     //
1795     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1796     if (!command_completed
1797             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1798             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1799 
1800         uint16_t opcode = little_endian_read_16(packet,3);
1801         if (opcode == hci_reset.opcode){
1802             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1803             return;
1804         }
1805     }
1806 
1807     // CSR & H5
1808     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1809     if (!command_completed
1810             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1811             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1812 
1813         uint16_t opcode = little_endian_read_16(packet,3);
1814         if (opcode == hci_reset.opcode){
1815             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1816             return;
1817         }
1818     }
1819 
1820     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1821     // fix: Correct substate and behave as command below
1822     if (command_completed){
1823         switch (hci_stack->substate){
1824             case HCI_INIT_SEND_RESET:
1825                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1826                 break;
1827             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1828                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1829                 break;
1830             default:
1831                 break;
1832         }
1833     }
1834 
1835 #endif
1836 
1837     if (!command_completed) return;
1838 
1839     bool need_baud_change = false;
1840     bool need_addr_change = false;
1841 
1842 #ifndef HAVE_HOST_CONTROLLER_API
1843     need_baud_change = hci_stack->config
1844                         && hci_stack->chipset
1845                         && hci_stack->chipset->set_baudrate_command
1846                         && hci_stack->hci_transport->set_baudrate
1847                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1848 
1849     need_addr_change = hci_stack->custom_bd_addr_set
1850                         && hci_stack->chipset
1851                         && hci_stack->chipset->set_bd_addr_command;
1852 #endif
1853 
1854     switch(hci_stack->substate){
1855 
1856 #ifndef HAVE_HOST_CONTROLLER_API
1857         case HCI_INIT_SEND_RESET:
1858             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1859             // fix: just correct substate and behave as command below
1860             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1861             btstack_run_loop_remove_timer(&hci_stack->timeout);
1862             break;
1863         case HCI_INIT_W4_SEND_RESET:
1864             btstack_run_loop_remove_timer(&hci_stack->timeout);
1865             break;
1866         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1867             log_info("Received local name, need baud change %d", (int) need_baud_change);
1868             if (need_baud_change){
1869                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1870                 return;
1871             }
1872             // skip baud change
1873             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1874             return;
1875         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1876             // for STLC2500D, baud rate change already happened.
1877             // for others, baud rate gets changed now
1878             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1879                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1880                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1881                 hci_stack->hci_transport->set_baudrate(baud_rate);
1882             }
1883             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1884             return;
1885         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1886             btstack_run_loop_remove_timer(&hci_stack->timeout);
1887             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1888             return;
1889         case HCI_INIT_W4_CUSTOM_INIT:
1890             // repeat custom init
1891             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1892             return;
1893 #else
1894         case HCI_INIT_W4_SEND_RESET:
1895             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1896             return ;
1897 #endif
1898 
1899         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1900             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1901               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1902                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1903                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1904                 return;
1905             }
1906             if (need_addr_change){
1907                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1908                 return;
1909             }
1910             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1911             return;
1912 #ifndef HAVE_HOST_CONTROLLER_API
1913         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1914             if (need_baud_change){
1915                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1916                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1917                 hci_stack->hci_transport->set_baudrate(baud_rate);
1918             }
1919             if (need_addr_change){
1920                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1921                 return;
1922             }
1923             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1924             return;
1925         case HCI_INIT_W4_SET_BD_ADDR:
1926             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1927             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1928             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1929                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1930                 return;
1931             }
1932             // skipping st warm boot
1933             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1934             return;
1935         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1936             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1937             return;
1938 #endif
1939         case HCI_INIT_W4_READ_BD_ADDR:
1940             // only read buffer size if supported
1941             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1942                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1943                 return;
1944             }
1945             // skipping read buffer size
1946             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1947             return;
1948         case HCI_INIT_W4_SET_EVENT_MASK:
1949             // skip Classic init commands for LE only chipsets
1950             if (!hci_classic_supported()){
1951 #ifdef ENABLE_BLE
1952                 if (hci_le_supported()){
1953                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1954                     return;
1955                 }
1956 #endif
1957                 log_error("Neither BR/EDR nor LE supported");
1958                 hci_init_done();
1959                 return;
1960             }
1961             if (!gap_ssp_supported()){
1962                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1963                 return;
1964             }
1965             break;
1966 #ifdef ENABLE_BLE
1967         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1968             // skip write le host if not supported (e.g. on LE only EM9301)
1969             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1970             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1971             return;
1972 
1973 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1974         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1975             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1976             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1977                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1978                 return;
1979             }
1980             // explicit fall through to reduce repetitions
1981 
1982 #ifdef ENABLE_LE_CENTRAL
1983             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1984 #else
1985             hci_init_done();
1986 #endif
1987             return;
1988 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1989 
1990 #endif  /* ENABLE_BLE */
1991 
1992         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1993             // skip write secure connections host support if not supported or disabled
1994             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1995                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1996                 return;
1997             }
1998             break;
1999 
2000 #ifdef ENABLE_SCO_OVER_HCI
2001         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2002             // skip write synchronous flow control if not supported
2003             if (hci_stack->local_supported_commands[0] & 0x04) break;
2004             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
2005 
2006             /* fall through */
2007 
2008         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2009             // skip write default erroneous data reporting if not supported
2010             if (hci_stack->local_supported_commands[0] & 0x08) break;
2011             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
2012 
2013             /* fall through */
2014 
2015         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
2016             // skip bcm set sco pcm config on non-Broadcom chipsets
2017             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
2018             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2019 
2020             /* fall through */
2021 
2022         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
2023             if (!hci_le_supported()){
2024                 // SKIP LE init for Classic only configuration
2025                 hci_init_done();
2026                 return;
2027             }
2028             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2029             break;
2030 
2031 #else /* !ENABLE_SCO_OVER_HCI */
2032 
2033         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2034 #ifdef ENABLE_SCO_OVER_PCM
2035             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
2036                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
2037                 return;
2038             }
2039 #endif
2040             /* fall through */
2041 
2042         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
2043 #ifdef ENABLE_BLE
2044             if (hci_le_supported()){
2045                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
2046                 return;
2047             }
2048 #endif
2049             // SKIP LE init for Classic only configuration
2050             hci_init_done();
2051             return;
2052 #endif /* ENABLE_SCO_OVER_HCI */
2053 
2054 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2055 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2056         // Response to command before init done state -> init done
2057         case (HCI_INIT_DONE-1):
2058             hci_init_done();
2059             return;
2060 #endif
2061 
2062         default:
2063             break;
2064     }
2065     hci_initializing_next_state();
2066 }
2067 
2068 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2069     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2070     bd_addr_t bd_address;
2071     (void)memcpy(&bd_address, conn->address, 6);
2072 
2073 #ifdef ENABLE_CLASSIC
2074     // cache needed data
2075     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2076 #endif
2077 
2078     // connection failed, remove entry
2079     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2080     btstack_memory_hci_connection_free( conn );
2081 
2082 #ifdef ENABLE_CLASSIC
2083     // notify client if dedicated bonding
2084     if (notify_dedicated_bonding_failed){
2085         log_info("hci notify_dedicated_bonding_failed");
2086         hci_emit_dedicated_bonding_result(bd_address, status);
2087     }
2088 
2089     // if authentication error, also delete link key
2090     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2091         gap_drop_link_key_for_bd_addr(bd_address);
2092     }
2093 #else
2094     UNUSED(status);
2095 #endif
2096 }
2097 
2098 #ifdef ENABLE_CLASSIC
2099 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2100     // SSP Controller
2101     if (features[6] & (1 << 3)){
2102         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2103     }
2104     // eSCO
2105     if (features[3] & (1<<7)){
2106         conn->remote_supported_features[0] |= 1;
2107     }
2108     // Extended features
2109     if (features[7] & (1<<7)){
2110         conn->remote_supported_features[0] |= 2;
2111     }
2112 }
2113 
2114 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2115     // SSP Host
2116     if (features[0] & (1 << 0)){
2117         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2118     }
2119     // SC Host
2120     if (features[0] & (1 << 3)){
2121         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2122     }
2123 }
2124 
2125 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2126     // SC Controller
2127     if (features[1] & (1 << 0)){
2128         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2129     }
2130 }
2131 
2132 static void hci_handle_remote_features_received(hci_connection_t * conn){
2133     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2134     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2135     if (conn->bonding_flags & BONDING_DEDICATED){
2136         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2137     }
2138 }
2139 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2140     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2141     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2142 }
2143 
2144 #endif
2145 
2146 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2147     // handle BT initialization
2148     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2149         hci_initializing_event_handler(packet, size);
2150     }
2151 
2152     // help with BT sleep
2153     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2154         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2155         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2156         hci_initializing_next_state();
2157     }
2158 }
2159 
2160 #ifdef ENABLE_CLASSIC
2161 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2162     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2163     conn->encryption_key_size = encryption_key_size;
2164 
2165     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2166         conn->requested_security_level = LEVEL_0;
2167         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2168         return;
2169     }
2170 
2171     // Request Authentication if not already done
2172     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2173     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2174 }
2175 #endif
2176 
2177 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2178     UNUSED(size);
2179 
2180     uint16_t manufacturer;
2181 #ifdef ENABLE_CLASSIC
2182     hci_con_handle_t handle;
2183     hci_connection_t * conn;
2184     uint8_t status;
2185 #endif
2186     // get num cmd packets - limit to 1 to reduce complexity
2187     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2188 
2189     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2190     switch (opcode){
2191         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2192             if (packet[5]) break;
2193             // terminate, name 248 chars
2194             packet[6+248] = 0;
2195             log_info("local name: %s", &packet[6]);
2196             break;
2197         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2198             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2199             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2200                 uint16_t acl_len = little_endian_read_16(packet, 6);
2201                 uint16_t sco_len = packet[8];
2202 
2203                 // determine usable ACL/SCO payload size
2204                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2205                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2206 
2207                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2208                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2209 
2210                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2211                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2212                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2213             }
2214             break;
2215         case HCI_OPCODE_HCI_READ_RSSI:
2216             if (packet[5] == ERROR_CODE_SUCCESS){
2217                 uint8_t event[5];
2218                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2219                 event[1] = 3;
2220                 (void)memcpy(&event[2], &packet[6], 3);
2221                 hci_emit_event(event, sizeof(event), 1);
2222             }
2223             break;
2224 #ifdef ENABLE_BLE
2225         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2226             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2227             hci_stack->le_acl_packets_total_num = packet[8];
2228             // determine usable ACL payload size
2229             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2230                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2231             }
2232             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2233             break;
2234 #endif
2235 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2236         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2237             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2238             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2239             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);
2240             break;
2241 #endif
2242 #ifdef ENABLE_LE_CENTRAL
2243         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2244             hci_stack->le_whitelist_capacity = packet[6];
2245             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2246             break;
2247 #endif
2248         case HCI_OPCODE_HCI_READ_BD_ADDR:
2249             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2250             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));
2251 #ifdef ENABLE_CLASSIC
2252             if (hci_stack->link_key_db){
2253                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2254             }
2255 #endif
2256             break;
2257 #ifdef ENABLE_CLASSIC
2258         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2259             hci_emit_discoverable_enabled(hci_stack->discoverable);
2260             break;
2261         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2262             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2263                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2264                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2265                 hci_emit_event(event, sizeof(event), 1);
2266             }
2267             break;
2268 #endif
2269         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2270             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2271 
2272 #ifdef ENABLE_CLASSIC
2273             // determine usable ACL packet types based on host buffer size and supported features
2274             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2275             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2276 #endif
2277             // Classic/LE
2278             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2279             break;
2280         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2281             manufacturer = little_endian_read_16(packet, 10);
2282             // map Cypress to Broadcom
2283             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2284                 log_info("Treat Cypress as Broadcom");
2285                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2286                 little_endian_store_16(packet, 10, manufacturer);
2287             }
2288             hci_stack->manufacturer = manufacturer;
2289             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2290             break;
2291         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2292             hci_stack->local_supported_commands[0] =
2293                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2294                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2295                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2296                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2297                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2298                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2299                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2300                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2301             hci_stack->local_supported_commands[1] =
2302                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2303                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2304                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2305                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2306                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2307             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2308             break;
2309 #ifdef ENABLE_CLASSIC
2310         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2311             if (packet[5]) return;
2312             hci_stack->synchronous_flow_control_enabled = 1;
2313             break;
2314         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2315             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2316             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2317             conn   = hci_connection_for_handle(handle);
2318             if (conn != NULL) {
2319                 uint8_t key_size = 0;
2320                 if (status == 0){
2321                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2322                     log_info("Handle %04x key Size: %u", handle, key_size);
2323                 } else {
2324                     key_size = 1;
2325                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2326                 }
2327                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2328             }
2329             break;
2330         // assert pairing complete event is emitted.
2331         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2332         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2333         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2334         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2335             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2336             // lookup connection by gap pairing addr
2337             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2338             if (conn == NULL) break;
2339             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2340             break;
2341 
2342 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2343         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2344         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2345             uint8_t event[67];
2346             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2347             event[1] = 65;
2348             (void)memset(&event[2], 0, 65);
2349             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2350                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2351                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2352                     event[2] = 3;
2353                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2354                 } else {
2355                     event[2] = 1;
2356                 }
2357             }
2358             hci_emit_event(event, sizeof(event), 0);
2359             break;
2360         }
2361 
2362         // note: only needed if user does not provide OOB data
2363         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2364             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2365             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2366             if (conn == NULL) break;
2367             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2368             break;
2369 #endif
2370 #endif
2371         default:
2372             break;
2373     }
2374 }
2375 
2376 #ifdef ENABLE_BLE
2377 static void event_handle_le_connection_complete(const uint8_t * packet){
2378 	bd_addr_t addr;
2379 	bd_addr_type_t addr_type;
2380 	hci_connection_t * conn;
2381 
2382 	// Connection management
2383 	reverse_bd_addr(&packet[8], addr);
2384 	addr_type = (bd_addr_type_t)packet[7];
2385 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2386 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2387 
2388 #ifdef ENABLE_LE_CENTRAL
2389 	// handle error: error is reported only to the initiator -> outgoing connection
2390 	if (packet[3]){
2391 
2392 		// handle cancelled outgoing connection
2393 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2394 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2395 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2396 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2397 		    // reset state
2398             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2399             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2400 			// get outgoing connection conn struct for direct connect
2401 			conn = gap_get_outgoing_connection();
2402 		}
2403 
2404 		// outgoing le connection establishment is done
2405 		if (conn){
2406 			// remove entry
2407 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2408 			btstack_memory_hci_connection_free( conn );
2409 		}
2410 		return;
2411 	}
2412 #endif
2413 
2414 	// on success, both hosts receive connection complete event
2415 	if (packet[6] == HCI_ROLE_MASTER){
2416 #ifdef ENABLE_LE_CENTRAL
2417 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2418 		// note: no hci_connection_t object exists yet for connect with whitelist
2419 		if (hci_is_le_connection_type(addr_type)){
2420 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2421 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2422 		}
2423 #endif
2424 	} else {
2425 #ifdef ENABLE_LE_PERIPHERAL
2426 		// if we're slave, it was an incoming connection, advertisements have stopped
2427 		hci_stack->le_advertisements_active = false;
2428 #endif
2429 	}
2430 
2431 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2432 	if (!conn){
2433 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2434 	}
2435 
2436 	// no memory, sorry.
2437 	if (!conn){
2438 		return;
2439 	}
2440 
2441 	conn->state = OPEN;
2442 	conn->role  = packet[6];
2443 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2444 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2445 
2446 #ifdef ENABLE_LE_PERIPHERAL
2447 	if (packet[6] == HCI_ROLE_SLAVE){
2448 		hci_update_advertisements_enabled_for_current_roles();
2449 	}
2450 #endif
2451 
2452     // init unenhanced att bearer mtu
2453     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2454     conn->att_connection.mtu_exchanged = false;
2455 
2456     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2457 
2458 	// restart timer
2459 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2460 	// btstack_run_loop_add_timer(&conn->timeout);
2461 
2462 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2463 
2464 	hci_emit_nr_connections_changed();
2465 }
2466 #endif
2467 
2468 #ifdef ENABLE_CLASSIC
2469 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){
2470     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2471     // LEVEL_4 is tested by l2cap
2472     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2473     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2474     if (level >= LEVEL_3){
2475         // MITM not possible without keyboard or display
2476         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2477         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2478 
2479         // MITM possible if one side has keyboard and the other has keyboard or display
2480         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2481         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2482 
2483         // MITM not possible if one side has only display and other side has no keyboard
2484         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2485         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2486     }
2487     // LEVEL 2 requires SSP, which is a given
2488     return true;
2489 }
2490 
2491 static bool btstack_is_null(uint8_t * data, uint16_t size){
2492     uint16_t i;
2493     for (i=0; i < size ; i++){
2494         if (data[i] != 0) {
2495             return false;
2496         }
2497     }
2498     return true;
2499 }
2500 
2501 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2502     // get requested security level
2503     gap_security_level_t requested_security_level = conn->requested_security_level;
2504     if (hci_stack->gap_secure_connections_only_mode){
2505         requested_security_level = LEVEL_4;
2506     }
2507 
2508     // assess security: LEVEL 4 requires SC
2509     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2510     if ((requested_security_level == LEVEL_4) &&
2511         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2512         !hci_remote_sc_enabled(conn)){
2513         log_info("Level 4 required, but SC not supported -> abort");
2514         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2515         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2516         return;
2517     }
2518 
2519     // assess security based on io capabilities
2520     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2521         // responder: fully validate io caps of both sides as well as OOB data
2522         bool security_possible = false;
2523         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2524 
2525 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2526         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2527         // so we merge the OOB data availability
2528         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2529         if (conn->classic_oob_c_192 != NULL){
2530             have_oob_data |= 1;
2531         }
2532         if (conn->classic_oob_c_256 != NULL){
2533             have_oob_data |= 2;
2534         }
2535         // for up to Level 3, either P-192 as well as P-256 will do
2536         // 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
2537         // if remote does not SC, we should not receive P-256 data either
2538         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2539             security_possible = true;
2540         }
2541         // for Level 4, P-256 is needed
2542         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2543             security_possible = true;
2544         }
2545 #endif
2546 
2547         if (security_possible == false){
2548             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2549             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2550             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2551             return;
2552         }
2553     } else {
2554         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2555 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2556 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2557         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2558             log_info("Level 3+ required, but no input/output -> abort");
2559             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2560             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2561             return;
2562         }
2563 #endif
2564 #endif
2565     }
2566 
2567 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2568     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2569         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2570     } else {
2571         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2572     }
2573 #endif
2574 }
2575 
2576 #endif
2577 
2578 static void event_handler(uint8_t *packet, uint16_t size){
2579 
2580     uint16_t event_length = packet[1];
2581 
2582     // assert packet is complete
2583     if (size != (event_length + 2u)){
2584         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2585         return;
2586     }
2587 
2588     bd_addr_type_t addr_type;
2589     hci_con_handle_t handle;
2590     hci_connection_t * conn;
2591     int i;
2592     int create_connection_cmd;
2593 
2594 #ifdef ENABLE_CLASSIC
2595     hci_link_type_t link_type;
2596     bd_addr_t addr;
2597 #endif
2598 
2599     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2600 
2601     switch (hci_event_packet_get_type(packet)) {
2602 
2603         case HCI_EVENT_COMMAND_COMPLETE:
2604             handle_command_complete_event(packet, size);
2605             break;
2606 
2607         case HCI_EVENT_COMMAND_STATUS:
2608             // get num cmd packets - limit to 1 to reduce complexity
2609             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2610 
2611             // check command status to detected failed outgoing connections
2612             create_connection_cmd = 0;
2613 #ifdef ENABLE_CLASSIC
2614             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2615                 create_connection_cmd = 1;
2616             }
2617 #endif
2618 #ifdef ENABLE_LE_CENTRAL
2619             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2620                 create_connection_cmd = 1;
2621             }
2622 #endif
2623             if (create_connection_cmd) {
2624                 uint8_t status = hci_event_command_status_get_status(packet);
2625                 addr_type = hci_stack->outgoing_addr_type;
2626                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2627                 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);
2628 
2629                 // reset outgoing address info
2630                 memset(hci_stack->outgoing_addr, 0, 6);
2631                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2632 
2633                 // on error
2634                 if (status != ERROR_CODE_SUCCESS){
2635 #ifdef ENABLE_LE_CENTRAL
2636                     if (hci_is_le_connection_type(addr_type)){
2637                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2638                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2639                     }
2640 #endif
2641                     // error => outgoing connection failed
2642                     if (conn != NULL){
2643                         hci_handle_connection_failed(conn, status);
2644                     }
2645                 }
2646             }
2647 
2648 #ifdef ENABLE_CLASSIC
2649             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2650                 uint8_t status = hci_event_command_status_get_status(packet);
2651                 log_info("command status (inquiry), status %x", status);
2652                 if (status == ERROR_CODE_SUCCESS) {
2653                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2654                 } else {
2655                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2656                 }
2657             }
2658 #endif
2659             break;
2660 
2661         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2662             if (size < 3) return;
2663             uint16_t num_handles = packet[2];
2664             if (size != (3u + num_handles * 4u)) return;
2665             uint16_t offset = 3;
2666             for (i=0; i<num_handles;i++){
2667                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2668                 offset += 2u;
2669                 uint16_t num_packets = little_endian_read_16(packet, offset);
2670                 offset += 2u;
2671 
2672                 conn = hci_connection_for_handle(handle);
2673                 if (!conn){
2674                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2675                     continue;
2676                 }
2677 
2678                 if (conn->num_packets_sent >= num_packets){
2679                     conn->num_packets_sent -= num_packets;
2680                 } else {
2681                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2682                     conn->num_packets_sent = 0;
2683                 }
2684                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2685 
2686 #ifdef ENABLE_CLASSIC
2687                 // For SCO, we do the can_send_now_check here
2688                 hci_notify_if_sco_can_send_now();
2689 #endif
2690             }
2691             break;
2692         }
2693 
2694 #ifdef ENABLE_CLASSIC
2695         case HCI_EVENT_INQUIRY_COMPLETE:
2696             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2697                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2698                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2699                 hci_emit_event(event, sizeof(event), 1);
2700             }
2701             break;
2702         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2703             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2704                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2705             }
2706             break;
2707         case HCI_EVENT_CONNECTION_REQUEST:
2708             reverse_bd_addr(&packet[2], addr);
2709             link_type = (hci_link_type_t) packet[11];
2710 
2711             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2712             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2713                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2714                 bd_addr_copy(hci_stack->decline_addr, addr);
2715                 break;
2716             }
2717 
2718             if (hci_stack->gap_classic_accept_callback != NULL){
2719                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2720                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2721                     bd_addr_copy(hci_stack->decline_addr, addr);
2722                     break;
2723                 }
2724             }
2725 
2726             // TODO: eval COD 8-10
2727             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2728             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2729             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2730             if (!conn) {
2731                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2732             }
2733             if (!conn) {
2734                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2735                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2736                 bd_addr_copy(hci_stack->decline_addr, addr);
2737                 break;
2738             }
2739             conn->role  = HCI_ROLE_SLAVE;
2740             conn->state = RECEIVED_CONNECTION_REQUEST;
2741             // store info about eSCO
2742             if (link_type == HCI_LINK_TYPE_ESCO){
2743                 conn->remote_supported_features[0] |= 1;
2744             }
2745             hci_run();
2746             break;
2747 
2748         case HCI_EVENT_CONNECTION_COMPLETE:
2749             // Connection management
2750             reverse_bd_addr(&packet[5], addr);
2751             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2752             addr_type = BD_ADDR_TYPE_ACL;
2753             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2754             if (conn) {
2755                 if (!packet[2]){
2756                     conn->state = OPEN;
2757                     conn->con_handle = little_endian_read_16(packet, 3);
2758 
2759                     // queue get remote feature
2760                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2761 
2762                     // queue set supervision timeout if we're master
2763                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2764                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2765                     }
2766 
2767                     // restart timer
2768                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2769                     btstack_run_loop_add_timer(&conn->timeout);
2770 
2771                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2772 
2773                     hci_emit_nr_connections_changed();
2774                 } else {
2775                     // connection failed
2776                     hci_handle_connection_failed(conn, packet[2]);
2777                 }
2778             }
2779             break;
2780 
2781         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2782             reverse_bd_addr(&packet[5], addr);
2783             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2784             if (packet[2]){
2785                 // connection failed
2786                 break;
2787             }
2788             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2789             if (!conn) {
2790                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2791             }
2792             if (!conn) {
2793                 break;
2794             }
2795             conn->state = OPEN;
2796             conn->con_handle = little_endian_read_16(packet, 3);
2797 
2798 #ifdef ENABLE_SCO_OVER_HCI
2799             // update SCO
2800             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2801                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2802             }
2803             // trigger can send now
2804             if (hci_have_usb_transport()){
2805                 hci_stack->sco_can_send_now = true;
2806             }
2807 #endif
2808 #ifdef HAVE_SCO_TRANSPORT
2809             // configure sco transport
2810             if (hci_stack->sco_transport != NULL){
2811                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2812                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2813             }
2814 #endif
2815             break;
2816 
2817         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2818             handle = little_endian_read_16(packet, 3);
2819             conn = hci_connection_for_handle(handle);
2820             if (!conn) break;
2821             if (!packet[2]){
2822                 const uint8_t * features = &packet[5];
2823                 hci_handle_remote_features_page_0(conn, features);
2824 
2825                 // read extended features if possible
2826                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2827                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2828                     break;
2829                 }
2830             }
2831             hci_handle_remote_features_received(conn);
2832             break;
2833 
2834         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2835             handle = little_endian_read_16(packet, 3);
2836             conn = hci_connection_for_handle(handle);
2837             if (!conn) break;
2838             // status = ok, page = 1
2839             if (!packet[2]) {
2840                 uint8_t page_number = packet[5];
2841                 uint8_t maximum_page_number = packet[6];
2842                 const uint8_t * features = &packet[7];
2843                 bool done = false;
2844                 switch (page_number){
2845                     case 1:
2846                         hci_handle_remote_features_page_1(conn, features);
2847                         if (maximum_page_number >= 2){
2848                             // get Secure Connections (Controller) from Page 2 if available
2849                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2850                         } else {
2851                             // otherwise, assume SC (Controller) == SC (Host)
2852                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2853                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2854                             }
2855                             done = true;
2856                         }
2857                         break;
2858                     case 2:
2859                         hci_handle_remote_features_page_2(conn, features);
2860                         done = true;
2861                         break;
2862                     default:
2863                         break;
2864                 }
2865                 if (!done) break;
2866             }
2867             hci_handle_remote_features_received(conn);
2868             break;
2869 
2870         case HCI_EVENT_LINK_KEY_REQUEST:
2871 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2872             hci_event_link_key_request_get_bd_addr(packet, addr);
2873             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2874             if (!conn) break;
2875 
2876             // lookup link key in db if not cached
2877             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2878                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2879             }
2880 
2881             // response sent by hci_run()
2882             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2883 #endif
2884             break;
2885 
2886         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2887             hci_event_link_key_request_get_bd_addr(packet, addr);
2888             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2889             if (!conn) break;
2890 
2891             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2892 
2893             // CVE-2020-26555: ignore NULL link key
2894             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2895             if (btstack_is_null(&packet[8], 16)) break;
2896 
2897             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2898             // Change Connection Encryption keeps link key type
2899             if (link_key_type != CHANGED_COMBINATION_KEY){
2900                 conn->link_key_type = link_key_type;
2901             }
2902 
2903             // cache link key. link keys stored in little-endian format for legacy reasons
2904             memcpy(&conn->link_key, &packet[8], 16);
2905 
2906             // only store link key:
2907             // - if bondable enabled
2908             if (hci_stack->bondable == false) break;
2909             // - if security level sufficient
2910             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2911             // - for SSP, also check if remote side requested bonding as well
2912             if (conn->link_key_type != COMBINATION_KEY){
2913                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2914                 if (!remote_bonding){
2915                     break;
2916                 }
2917             }
2918             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2919             break;
2920         }
2921 
2922         case HCI_EVENT_PIN_CODE_REQUEST:
2923             hci_event_pin_code_request_get_bd_addr(packet, addr);
2924             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2925             if (!conn) break;
2926 
2927             hci_pairing_started(conn, false);
2928             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2929             if (!hci_stack->bondable ){
2930                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2931                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2932                 hci_run();
2933                 return;
2934             }
2935             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2936             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2937                 log_info("Level 4 required, but SC not supported -> abort");
2938                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2939                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2940                 hci_run();
2941                 return;
2942             }
2943             break;
2944 
2945         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2946             hci_event_io_capability_response_get_bd_addr(packet, addr);
2947             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2948             if (!conn) break;
2949 
2950             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2951             hci_pairing_started(conn, true);
2952             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2953             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2954 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2955             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2956 #endif
2957             break;
2958 
2959         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2960             hci_event_io_capability_response_get_bd_addr(packet, addr);
2961             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2962             if (!conn) break;
2963 
2964             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2965             hci_connection_timestamp(conn);
2966             hci_pairing_started(conn, true);
2967             break;
2968 
2969 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2970         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2971             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2972             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2973             if (!conn) break;
2974 
2975             hci_connection_timestamp(conn);
2976 
2977             hci_pairing_started(conn, true);
2978 
2979             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2980             break;
2981 #endif
2982 
2983         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2984             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2985             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2986             if (!conn) break;
2987             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2988                 if (hci_stack->ssp_auto_accept){
2989                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2990                 };
2991             } else {
2992                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2993                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2994                 // don't forward event to app
2995                 hci_run();
2996                 return;
2997             }
2998             break;
2999 
3000         case HCI_EVENT_USER_PASSKEY_REQUEST:
3001             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
3002             if (hci_stack->ssp_auto_accept){
3003                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
3004             };
3005             break;
3006 
3007         case HCI_EVENT_MODE_CHANGE:
3008             handle = hci_event_mode_change_get_handle(packet);
3009             conn = hci_connection_for_handle(handle);
3010             if (!conn) break;
3011             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3012             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3013             break;
3014 #endif
3015 
3016         case HCI_EVENT_ENCRYPTION_CHANGE:
3017             handle = hci_event_encryption_change_get_connection_handle(packet);
3018             conn = hci_connection_for_handle(handle);
3019             if (!conn) break;
3020             if (hci_event_encryption_change_get_status(packet) == 0u) {
3021                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3022                 if (encryption_enabled){
3023                     if (hci_is_le_connection(conn)){
3024                         // For LE, we accept connection as encrypted
3025                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3026                     }
3027 #ifdef ENABLE_CLASSIC
3028                     else {
3029 
3030                         // dedicated bonding: send result and disconnect
3031                         if (conn->bonding_flags & BONDING_DEDICATED){
3032                             conn->bonding_flags &= ~BONDING_DEDICATED;
3033                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3034                             conn->bonding_status = packet[2];
3035                             break;
3036                         }
3037 
3038                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3039                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3040                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3041                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3042                             log_info("SC during pairing, but only E0 now -> abort");
3043                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3044                             break;
3045                         }
3046 
3047                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3048                         if (connected_uses_aes_ccm){
3049                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3050                         }
3051 
3052 #ifdef ENABLE_TESTING_SUPPORT
3053                         // work around for issue with PTS dongle
3054                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3055 #endif
3056 
3057                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3058                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3059                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3060                         } else {
3061                             // if not, pretend everything is perfect
3062                             hci_handle_read_encryption_key_size_complete(conn, 16);
3063                         }
3064                     }
3065 #endif
3066                 } else {
3067                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3068                 }
3069             }
3070 
3071             break;
3072 
3073 #ifdef ENABLE_CLASSIC
3074         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3075             handle = hci_event_authentication_complete_get_connection_handle(packet);
3076             conn = hci_connection_for_handle(handle);
3077             if (!conn) break;
3078 
3079             // clear authentication active flag
3080             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3081             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3082 
3083             // authenticated only if auth status == 0
3084             if (hci_event_authentication_complete_get_status(packet) == 0){
3085                 // authenticated
3086                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3087 
3088                 // If not already encrypted, start encryption
3089                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3090                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3091                     break;
3092                 }
3093             }
3094 
3095             // emit updated security level
3096             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3097             break;
3098 
3099         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3100             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3101             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3102             if (!conn) break;
3103 
3104             // treat successfully paired connection as authenticated
3105             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3106                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3107             }
3108 
3109             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3110             break;
3111 #endif
3112 
3113         // HCI_EVENT_DISCONNECTION_COMPLETE
3114         // has been split, to first notify stack before shutting connection down
3115         // see end of function, too.
3116         case HCI_EVENT_DISCONNECTION_COMPLETE:
3117             if (packet[2]) break;   // status != 0
3118             handle = little_endian_read_16(packet, 3);
3119             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3120             if (hci_stack->acl_fragmentation_total_size > 0u) {
3121                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3122                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3123                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3124                     hci_stack->acl_fragmentation_total_size = 0;
3125                     hci_stack->acl_fragmentation_pos = 0;
3126                     if (release_buffer){
3127                         hci_release_packet_buffer();
3128                     }
3129                 }
3130             }
3131 
3132             conn = hci_connection_for_handle(handle);
3133             if (!conn) break;
3134 #ifdef ENABLE_CLASSIC
3135             // pairing failed if it was ongoing
3136             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3137 #endif
3138 
3139             // emit dedicatd bonding event
3140             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3141                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3142             }
3143 
3144             // mark connection for shutdown, stop timers, reset state
3145             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3146             hci_connection_stop_timer(conn);
3147             hci_connection_init(conn);
3148 
3149 #ifdef ENABLE_BLE
3150 #ifdef ENABLE_LE_PERIPHERAL
3151             // re-enable advertisements for le connections if active
3152             if (hci_is_le_connection(conn)){
3153                 hci_update_advertisements_enabled_for_current_roles();
3154             }
3155 #endif
3156 #endif
3157             break;
3158 
3159         case HCI_EVENT_HARDWARE_ERROR:
3160             log_error("Hardware Error: 0x%02x", packet[2]);
3161             if (hci_stack->hardware_error_callback){
3162                 (*hci_stack->hardware_error_callback)(packet[2]);
3163             } else {
3164                 // if no special requests, just reboot stack
3165                 hci_power_control_off();
3166                 hci_power_control_on();
3167             }
3168             break;
3169 
3170 #ifdef ENABLE_CLASSIC
3171         case HCI_EVENT_ROLE_CHANGE:
3172             if (packet[2]) break;   // status != 0
3173             reverse_bd_addr(&packet[3], addr);
3174             addr_type = BD_ADDR_TYPE_ACL;
3175             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3176             if (!conn) break;
3177             conn->role = packet[9];
3178             break;
3179 #endif
3180 
3181         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3182             // release packet buffer only for asynchronous transport and if there are not further fragements
3183             if (hci_transport_synchronous()) {
3184                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3185                 return; // instead of break: to avoid re-entering hci_run()
3186             }
3187             hci_stack->acl_fragmentation_tx_active = 0;
3188             if (hci_stack->acl_fragmentation_total_size) break;
3189             hci_release_packet_buffer();
3190 
3191             // L2CAP receives this event via the hci_emit_event below
3192 
3193 #ifdef ENABLE_CLASSIC
3194             // For SCO, we do the can_send_now_check here
3195             hci_notify_if_sco_can_send_now();
3196 #endif
3197             break;
3198 
3199 #ifdef ENABLE_CLASSIC
3200         case HCI_EVENT_SCO_CAN_SEND_NOW:
3201             // For SCO, we do the can_send_now_check here
3202             hci_stack->sco_can_send_now = true;
3203             hci_notify_if_sco_can_send_now();
3204             return;
3205 
3206         // explode inquriy results for easier consumption
3207         case HCI_EVENT_INQUIRY_RESULT:
3208         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3209         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3210             gap_inquiry_explode(packet, size);
3211             break;
3212 #endif
3213 
3214 #ifdef ENABLE_BLE
3215         case HCI_EVENT_LE_META:
3216             switch (packet[2]){
3217 #ifdef ENABLE_LE_CENTRAL
3218                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3219                     // log_info("advertising report received");
3220                     if (!hci_stack->le_scanning_enabled) break;
3221                     le_handle_advertisement_report(packet, size);
3222                     break;
3223 #endif
3224                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3225 					event_handle_le_connection_complete(packet);
3226                     break;
3227 
3228                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3229                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3230                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3231                     conn = hci_connection_for_handle(handle);
3232                     if (!conn) break;
3233                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3234                     break;
3235 
3236                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3237                     // connection
3238                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3239                     conn = hci_connection_for_handle(handle);
3240                     if (conn) {
3241                         // read arguments
3242                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3243                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3244                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3245                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3246 
3247                         // validate against current connection parameter range
3248                         le_connection_parameter_range_t existing_range;
3249                         gap_get_connection_parameter_range(&existing_range);
3250                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3251                         if (update_parameter){
3252                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3253                             conn->le_conn_interval_min = le_conn_interval_min;
3254                             conn->le_conn_interval_max = le_conn_interval_max;
3255                             conn->le_conn_latency = le_conn_latency;
3256                             conn->le_supervision_timeout = le_supervision_timeout;
3257                         } else {
3258                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3259                         }
3260                     }
3261                     break;
3262 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3263                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3264                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3265                     conn = hci_connection_for_handle(handle);
3266                     if (conn) {
3267                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3268                     }
3269                     break;
3270 #endif
3271                 default:
3272                     break;
3273             }
3274             break;
3275 #endif
3276         case HCI_EVENT_VENDOR_SPECIFIC:
3277             // Vendor specific commands often create vendor specific event instead of num completed packets
3278             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3279             switch (hci_stack->manufacturer){
3280                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3281                     hci_stack->num_cmd_packets = 1;
3282                     break;
3283                 default:
3284                     break;
3285             }
3286             break;
3287         default:
3288             break;
3289     }
3290 
3291     handle_event_for_current_stack_state(packet, size);
3292 
3293     // notify upper stack
3294 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3295 
3296     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3297     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3298 		handle = little_endian_read_16(packet, 3);
3299 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3300 		// discard connection if app did not trigger a reconnect in the event handler
3301 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3302 			hci_shutdown_connection(aConn);
3303 		}
3304     }
3305 
3306 	// execute main loop
3307 	hci_run();
3308 }
3309 
3310 #ifdef ENABLE_CLASSIC
3311 
3312 #ifdef ENABLE_SCO_OVER_HCI
3313 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3314 static void sco_schedule_tx(hci_connection_t * conn);
3315 
3316 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3317     log_debug("SCO TX Timeout");
3318     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3319     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3320     if (!conn) return;
3321 
3322     // trigger send
3323     conn->sco_tx_ready = 1;
3324     // extra packet if CVSD but SCO buffer is too short
3325     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3326         conn->sco_tx_ready++;
3327     }
3328     hci_notify_if_sco_can_send_now();
3329 }
3330 
3331 
3332 #define SCO_TX_AFTER_RX_MS (6)
3333 
3334 static void sco_schedule_tx(hci_connection_t * conn){
3335 
3336     uint32_t now = btstack_run_loop_get_time_ms();
3337     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3338     int time_delta_ms = sco_tx_ms - now;
3339 
3340     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3341 
3342     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3343     btstack_run_loop_remove_timer(timer);
3344     btstack_run_loop_set_timer(timer, time_delta_ms);
3345     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3346     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3347     btstack_run_loop_add_timer(timer);
3348 }
3349 #endif
3350 
3351 static void sco_handler(uint8_t * packet, uint16_t size){
3352     // lookup connection struct
3353     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3354     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3355     if (!conn) return;
3356 
3357 #ifdef ENABLE_SCO_OVER_HCI
3358     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3359     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3360         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3361             packet[2] = 0x3c;
3362             memmove(&packet[3], &packet[23], 63);
3363             size = 63;
3364         }
3365     }
3366 
3367     if (hci_have_usb_transport()){
3368         // Nothing to do
3369     } else {
3370         // 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);
3371         if (hci_stack->synchronous_flow_control_enabled == 0){
3372             uint32_t now = btstack_run_loop_get_time_ms();
3373 
3374             if (!conn->sco_rx_valid){
3375                 // ignore first 10 packets
3376                 conn->sco_rx_count++;
3377                 // log_debug("sco rx count %u", conn->sco_rx_count);
3378                 if (conn->sco_rx_count == 10) {
3379                     // use first timestamp as is and pretent it just started
3380                     conn->sco_rx_ms = now;
3381                     conn->sco_rx_valid = 1;
3382                     conn->sco_rx_count = 0;
3383                     sco_schedule_tx(conn);
3384                 }
3385             } else {
3386                 // track expected arrival timme
3387                 conn->sco_rx_count++;
3388                 conn->sco_rx_ms += 7;
3389                 int delta = (int32_t) (now - conn->sco_rx_ms);
3390                 if (delta > 0){
3391                     conn->sco_rx_ms++;
3392                 }
3393                 // log_debug("sco rx %u", conn->sco_rx_ms);
3394                 sco_schedule_tx(conn);
3395             }
3396         }
3397     }
3398 #endif
3399 
3400     // deliver to app
3401     if (hci_stack->sco_packet_handler) {
3402         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3403     }
3404 
3405 #ifdef HAVE_SCO_TRANSPORT
3406     // We can send one packet for each received packet
3407     conn->sco_tx_ready++;
3408     hci_notify_if_sco_can_send_now();
3409 #endif
3410 
3411 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3412     conn->num_packets_completed++;
3413     hci_stack->host_completed_packets = 1;
3414     hci_run();
3415 #endif
3416 }
3417 #endif
3418 
3419 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3420     hci_dump_packet(packet_type, 1, packet, size);
3421     switch (packet_type) {
3422         case HCI_EVENT_PACKET:
3423             event_handler(packet, size);
3424             break;
3425         case HCI_ACL_DATA_PACKET:
3426             acl_handler(packet, size);
3427             break;
3428 #ifdef ENABLE_CLASSIC
3429         case HCI_SCO_DATA_PACKET:
3430             sco_handler(packet, size);
3431             break;
3432 #endif
3433         default:
3434             break;
3435     }
3436 }
3437 
3438 /**
3439  * @brief Add event packet handler.
3440  */
3441 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3442     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3443 }
3444 
3445 
3446 /** Register HCI packet handlers */
3447 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3448     hci_stack->acl_packet_handler = handler;
3449 }
3450 
3451 #ifdef ENABLE_CLASSIC
3452 /**
3453  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3454  */
3455 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3456     hci_stack->sco_packet_handler = handler;
3457 }
3458 #endif
3459 
3460 static void hci_state_reset(void){
3461     // no connections yet
3462     hci_stack->connections = NULL;
3463 
3464     // keep discoverable/connectable as this has been requested by the client(s)
3465     // hci_stack->discoverable = 0;
3466     // hci_stack->connectable = 0;
3467     // hci_stack->bondable = 1;
3468     // hci_stack->own_addr_type = 0;
3469 
3470     // buffer is free
3471     hci_stack->hci_packet_buffer_reserved = false;
3472 
3473     // no pending cmds
3474     hci_stack->decline_reason = 0;
3475 
3476     hci_stack->secure_connections_active = false;
3477 
3478 #ifdef ENABLE_CLASSIC
3479     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3480     hci_stack->gap_tasks =
3481             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3482             GAP_TASK_SET_CLASS_OF_DEVICE |
3483             GAP_TASK_SET_LOCAL_NAME |
3484             GAP_TASK_SET_EIR_DATA |
3485             GAP_TASK_WRITE_SCAN_ENABLE;
3486 #endif
3487 
3488 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3489     hci_stack->classic_read_local_oob_data = true;
3490     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3491 #endif
3492 
3493     // LE
3494 #ifdef ENABLE_BLE
3495     memset(hci_stack->le_random_address, 0, 6);
3496     hci_stack->le_random_address_set = 0;
3497 #endif
3498 #ifdef ENABLE_LE_CENTRAL
3499     hci_stack->le_scanning_active  = false;
3500     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3501     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3502     hci_stack->le_whitelist_capacity = 0;
3503 #endif
3504 #ifdef ENABLE_LE_PERIPHERAL
3505     hci_stack->le_advertisements_active = false;
3506     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3507         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3508     }
3509     if (hci_stack->le_advertisements_data != NULL){
3510         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3511     }
3512 #endif
3513 }
3514 
3515 #ifdef ENABLE_CLASSIC
3516 /**
3517  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3518  */
3519 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3520     // store and open remote device db
3521     hci_stack->link_key_db = link_key_db;
3522     if (hci_stack->link_key_db) {
3523         hci_stack->link_key_db->open();
3524     }
3525 }
3526 #endif
3527 
3528 void hci_init(const hci_transport_t *transport, const void *config){
3529 
3530 #ifdef HAVE_MALLOC
3531     if (!hci_stack) {
3532         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3533     }
3534 #else
3535     hci_stack = &hci_stack_static;
3536 #endif
3537     memset(hci_stack, 0, sizeof(hci_stack_t));
3538 
3539     // reference to use transport layer implementation
3540     hci_stack->hci_transport = transport;
3541 
3542     // reference to used config
3543     hci_stack->config = config;
3544 
3545     // setup pointer for outgoing packet buffer
3546     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3547 
3548     // max acl payload size defined in config.h
3549     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3550 
3551     // register packet handlers with transport
3552     transport->register_packet_handler(&packet_handler);
3553 
3554     hci_stack->state = HCI_STATE_OFF;
3555 
3556     // class of device
3557     hci_stack->class_of_device = 0x007a020c; // Smartphone
3558 
3559     // bondable by default
3560     hci_stack->bondable = 1;
3561 
3562 #ifdef ENABLE_CLASSIC
3563     // classic name
3564     hci_stack->local_name = default_classic_name;
3565 
3566     // Master slave policy
3567     hci_stack->master_slave_policy = 1;
3568 
3569     // Allow Role Switch
3570     hci_stack->allow_role_switch = 1;
3571 
3572     // Default / minimum security level = 2
3573     hci_stack->gap_security_level = LEVEL_2;
3574 
3575     // Default Security Mode 4
3576     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3577 
3578     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3579     hci_stack->gap_required_encyrption_key_size = 7;
3580 
3581     // Link Supervision Timeout
3582     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3583 
3584 #endif
3585 
3586     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3587     hci_stack->ssp_enable = 1;
3588     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3589     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3590     hci_stack->ssp_auto_accept = 1;
3591 
3592     // Secure Connections: enable (requires support from Controller)
3593     hci_stack->secure_connections_enable = true;
3594 
3595     // voice setting - signed 16 bit pcm data with CVSD over the air
3596     hci_stack->sco_voice_setting = 0x60;
3597 
3598 #ifdef ENABLE_LE_CENTRAL
3599     // connection parameter to use for outgoing connections
3600     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3601     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3602     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3603     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3604     hci_stack->le_connection_latency      = 4;         // 4
3605     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3606     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3607     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3608 
3609     // default LE Scanning
3610     hci_stack->le_scan_type     =   0x1; // active
3611     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3612     hci_stack->le_scan_window   =  0x30; //  30 ms
3613 #endif
3614 
3615 #ifdef ENABLE_LE_PERIPHERAL
3616     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3617 #endif
3618 
3619     // connection parameter range used to answer connection parameter update requests in l2cap
3620     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3621     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3622     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3623     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3624     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3625     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3626 
3627     hci_state_reset();
3628 }
3629 
3630 void hci_deinit(void){
3631 #ifdef HAVE_MALLOC
3632     if (hci_stack) {
3633         free(hci_stack);
3634     }
3635 #endif
3636     hci_stack = NULL;
3637 
3638 #ifdef ENABLE_CLASSIC
3639     disable_l2cap_timeouts = 0;
3640 #endif
3641 }
3642 
3643 /**
3644  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3645  */
3646 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3647     hci_stack->chipset = chipset_driver;
3648 
3649     // reset chipset driver - init is also called on power_up
3650     if (hci_stack->chipset && hci_stack->chipset->init){
3651         hci_stack->chipset->init(hci_stack->config);
3652     }
3653 }
3654 
3655 /**
3656  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3657  */
3658 void hci_set_control(const btstack_control_t *hardware_control){
3659     // references to used control implementation
3660     hci_stack->control = hardware_control;
3661     // init with transport config
3662     hardware_control->init(hci_stack->config);
3663 }
3664 
3665 void hci_close(void){
3666 
3667 #ifdef ENABLE_CLASSIC
3668     // close remote device db
3669     if (hci_stack->link_key_db) {
3670         hci_stack->link_key_db->close();
3671     }
3672 #endif
3673 
3674     btstack_linked_list_iterator_t lit;
3675     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3676     while (btstack_linked_list_iterator_has_next(&lit)){
3677         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3678         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3679         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3680         hci_shutdown_connection(connection);
3681     }
3682 
3683     hci_power_control(HCI_POWER_OFF);
3684 
3685 #ifdef HAVE_MALLOC
3686     free(hci_stack);
3687 #endif
3688     hci_stack = NULL;
3689 }
3690 
3691 #ifdef HAVE_SCO_TRANSPORT
3692 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3693     hci_stack->sco_transport = sco_transport;
3694     sco_transport->register_packet_handler(&packet_handler);
3695 }
3696 #endif
3697 
3698 #ifdef ENABLE_CLASSIC
3699 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3700     // validate ranage and set
3701     if (encryption_key_size < 7)  return;
3702     if (encryption_key_size > 16) return;
3703     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3704 }
3705 
3706 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3707     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3708         hci_stack->gap_security_mode = security_mode;
3709         return ERROR_CODE_SUCCESS;
3710     } else {
3711         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3712     }
3713 }
3714 
3715 gap_security_mode_t gap_get_security_mode(void){
3716     return hci_stack->gap_security_mode;
3717 }
3718 
3719 void gap_set_security_level(gap_security_level_t security_level){
3720     hci_stack->gap_security_level = security_level;
3721 }
3722 
3723 gap_security_level_t gap_get_security_level(void){
3724     if (hci_stack->gap_secure_connections_only_mode){
3725         return LEVEL_4;
3726     }
3727     return hci_stack->gap_security_level;
3728 }
3729 
3730 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3731     hci_stack->gap_minimal_service_security_level = security_level;
3732 }
3733 
3734 void gap_set_secure_connections_only_mode(bool enable){
3735     hci_stack->gap_secure_connections_only_mode = enable;
3736 }
3737 
3738 bool gap_get_secure_connections_only_mode(void){
3739     return hci_stack->gap_secure_connections_only_mode;
3740 }
3741 #endif
3742 
3743 #ifdef ENABLE_CLASSIC
3744 void gap_set_class_of_device(uint32_t class_of_device){
3745     hci_stack->class_of_device = class_of_device;
3746     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3747     hci_run();
3748 }
3749 
3750 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3751     hci_stack->default_link_policy_settings = default_link_policy_settings;
3752     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3753     hci_run();
3754 }
3755 
3756 void gap_set_allow_role_switch(bool allow_role_switch){
3757     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3758 }
3759 
3760 uint8_t hci_get_allow_role_switch(void){
3761     return  hci_stack->allow_role_switch;
3762 }
3763 
3764 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3765     hci_stack->link_supervision_timeout = link_supervision_timeout;
3766 }
3767 
3768 void hci_disable_l2cap_timeout_check(void){
3769     disable_l2cap_timeouts = 1;
3770 }
3771 #endif
3772 
3773 #ifndef HAVE_HOST_CONTROLLER_API
3774 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3775 void hci_set_bd_addr(bd_addr_t addr){
3776     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3777     hci_stack->custom_bd_addr_set = 1;
3778 }
3779 #endif
3780 
3781 // State-Module-Driver overview
3782 // state                    module  low-level
3783 // HCI_STATE_OFF             off      close
3784 // HCI_STATE_INITIALIZING,   on       open
3785 // HCI_STATE_WORKING,        on       open
3786 // HCI_STATE_HALTING,        on       open
3787 // HCI_STATE_SLEEPING,    off/sleep   close
3788 // HCI_STATE_FALLING_ASLEEP  on       open
3789 
3790 static int hci_power_control_on(void){
3791 
3792     // power on
3793     int err = 0;
3794     if (hci_stack->control && hci_stack->control->on){
3795         err = (*hci_stack->control->on)();
3796     }
3797     if (err){
3798         log_error( "POWER_ON failed");
3799         hci_emit_hci_open_failed();
3800         return err;
3801     }
3802 
3803     // int chipset driver
3804     if (hci_stack->chipset && hci_stack->chipset->init){
3805         hci_stack->chipset->init(hci_stack->config);
3806     }
3807 
3808     // init transport
3809     if (hci_stack->hci_transport->init){
3810         hci_stack->hci_transport->init(hci_stack->config);
3811     }
3812 
3813     // open transport
3814     err = hci_stack->hci_transport->open();
3815     if (err){
3816         log_error( "HCI_INIT failed, turning Bluetooth off again");
3817         if (hci_stack->control && hci_stack->control->off){
3818             (*hci_stack->control->off)();
3819         }
3820         hci_emit_hci_open_failed();
3821         return err;
3822     }
3823     return 0;
3824 }
3825 
3826 static void hci_power_control_off(void){
3827 
3828     log_info("hci_power_control_off");
3829 
3830     // close low-level device
3831     hci_stack->hci_transport->close();
3832 
3833     log_info("hci_power_control_off - hci_transport closed");
3834 
3835     // power off
3836     if (hci_stack->control && hci_stack->control->off){
3837         (*hci_stack->control->off)();
3838     }
3839 
3840     log_info("hci_power_control_off - control closed");
3841 
3842     hci_stack->state = HCI_STATE_OFF;
3843 }
3844 
3845 static void hci_power_control_sleep(void){
3846 
3847     log_info("hci_power_control_sleep");
3848 
3849 #if 0
3850     // don't close serial port during sleep
3851 
3852     // close low-level device
3853     hci_stack->hci_transport->close(hci_stack->config);
3854 #endif
3855 
3856     // sleep mode
3857     if (hci_stack->control && hci_stack->control->sleep){
3858         (*hci_stack->control->sleep)();
3859     }
3860 
3861     hci_stack->state = HCI_STATE_SLEEPING;
3862 }
3863 
3864 static int hci_power_control_wake(void){
3865 
3866     log_info("hci_power_control_wake");
3867 
3868     // wake on
3869     if (hci_stack->control && hci_stack->control->wake){
3870         (*hci_stack->control->wake)();
3871     }
3872 
3873 #if 0
3874     // open low-level device
3875     int err = hci_stack->hci_transport->open(hci_stack->config);
3876     if (err){
3877         log_error( "HCI_INIT failed, turning Bluetooth off again");
3878         if (hci_stack->control && hci_stack->control->off){
3879             (*hci_stack->control->off)();
3880         }
3881         hci_emit_hci_open_failed();
3882         return err;
3883     }
3884 #endif
3885 
3886     return 0;
3887 }
3888 
3889 static void hci_power_transition_to_initializing(void){
3890     // set up state machine
3891     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3892     hci_stack->hci_packet_buffer_reserved = false;
3893     hci_stack->state = HCI_STATE_INITIALIZING;
3894     hci_stack->substate = HCI_INIT_SEND_RESET;
3895 }
3896 
3897 // returns error
3898 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3899     int err;
3900     switch (power_mode){
3901         case HCI_POWER_ON:
3902             err = hci_power_control_on();
3903             if (err != 0) {
3904                 log_error("hci_power_control_on() error %d", err);
3905                 return err;
3906             }
3907             hci_power_transition_to_initializing();
3908             break;
3909         case HCI_POWER_OFF:
3910             // do nothing
3911             break;
3912         case HCI_POWER_SLEEP:
3913             // do nothing (with SLEEP == OFF)
3914             break;
3915         default:
3916             btstack_assert(false);
3917             break;
3918     }
3919     return ERROR_CODE_SUCCESS;
3920 }
3921 
3922 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3923     switch (power_mode){
3924         case HCI_POWER_ON:
3925             // do nothing
3926             break;
3927         case HCI_POWER_OFF:
3928             // no connections yet, just turn it off
3929             hci_power_control_off();
3930             break;
3931         case HCI_POWER_SLEEP:
3932             // no connections yet, just turn it off
3933             hci_power_control_sleep();
3934             break;
3935         default:
3936             btstack_assert(false);
3937             break;
3938     }
3939     return ERROR_CODE_SUCCESS;
3940 }
3941 
3942 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3943     switch (power_mode){
3944         case HCI_POWER_ON:
3945             // do nothing
3946             break;
3947         case HCI_POWER_OFF:
3948             // see hci_run
3949             hci_stack->state = HCI_STATE_HALTING;
3950             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3951             break;
3952         case HCI_POWER_SLEEP:
3953             // see hci_run
3954             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3955             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3956             break;
3957         default:
3958             btstack_assert(false);
3959             break;
3960     }
3961     return ERROR_CODE_SUCCESS;
3962 }
3963 
3964 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3965     switch (power_mode){
3966         case HCI_POWER_ON:
3967             hci_power_transition_to_initializing();
3968             break;
3969         case HCI_POWER_OFF:
3970             // do nothing
3971             break;
3972         case HCI_POWER_SLEEP:
3973             // see hci_run
3974             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3975             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3976             break;
3977         default:
3978             btstack_assert(false);
3979             break;
3980     }
3981     return ERROR_CODE_SUCCESS;
3982 }
3983 
3984 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3985     switch (power_mode){
3986         case HCI_POWER_ON:
3987             hci_power_transition_to_initializing();
3988             break;
3989         case HCI_POWER_OFF:
3990             // see hci_run
3991             hci_stack->state = HCI_STATE_HALTING;
3992             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3993             break;
3994         case HCI_POWER_SLEEP:
3995             // do nothing
3996             break;
3997         default:
3998             btstack_assert(false);
3999             break;
4000     }
4001     return ERROR_CODE_SUCCESS;
4002 }
4003 
4004 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4005     int err;
4006     switch (power_mode){
4007         case HCI_POWER_ON:
4008             err = hci_power_control_wake();
4009             if (err) return err;
4010             hci_power_transition_to_initializing();
4011             break;
4012         case HCI_POWER_OFF:
4013             hci_stack->state = HCI_STATE_HALTING;
4014             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4015             break;
4016         case HCI_POWER_SLEEP:
4017             // do nothing
4018             break;
4019         default:
4020             btstack_assert(false);
4021             break;
4022     }
4023     return ERROR_CODE_SUCCESS;
4024 }
4025 
4026 int hci_power_control(HCI_POWER_MODE power_mode){
4027     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4028     int err = 0;
4029     switch (hci_stack->state){
4030         case HCI_STATE_OFF:
4031             err = hci_power_control_state_off(power_mode);
4032             break;
4033         case HCI_STATE_INITIALIZING:
4034             err = hci_power_control_state_initializing(power_mode);
4035             break;
4036         case HCI_STATE_WORKING:
4037             err = hci_power_control_state_working(power_mode);
4038             break;
4039         case HCI_STATE_HALTING:
4040             err = hci_power_control_state_halting(power_mode);
4041             break;
4042         case HCI_STATE_FALLING_ASLEEP:
4043             err = hci_power_control_state_falling_asleep(power_mode);
4044             break;
4045         case HCI_STATE_SLEEPING:
4046             err = hci_power_control_state_sleeping(power_mode);
4047             break;
4048         default:
4049             btstack_assert(false);
4050             break;
4051     }
4052     if (err != 0){
4053         return err;
4054     }
4055 
4056     // create internal event
4057 	hci_emit_state();
4058 
4059 	// trigger next/first action
4060 	hci_run();
4061 
4062     return 0;
4063 }
4064 
4065 
4066 #ifdef ENABLE_CLASSIC
4067 
4068 static void hci_update_scan_enable(void){
4069     // 2 = page scan, 1 = inq scan
4070     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4071     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4072     hci_run();
4073 }
4074 
4075 void gap_discoverable_control(uint8_t enable){
4076     if (enable) enable = 1; // normalize argument
4077 
4078     if (hci_stack->discoverable == enable){
4079         hci_emit_discoverable_enabled(hci_stack->discoverable);
4080         return;
4081     }
4082 
4083     hci_stack->discoverable = enable;
4084     hci_update_scan_enable();
4085 }
4086 
4087 void gap_connectable_control(uint8_t enable){
4088     if (enable) enable = 1; // normalize argument
4089 
4090     // don't emit event
4091     if (hci_stack->connectable == enable) return;
4092 
4093     hci_stack->connectable = enable;
4094     hci_update_scan_enable();
4095 }
4096 #endif
4097 
4098 void gap_local_bd_addr(bd_addr_t address_buffer){
4099     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4100 }
4101 
4102 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4103 static void hci_host_num_completed_packets(void){
4104 
4105     // create packet manually as arrays are not supported and num_commands should not get reduced
4106     hci_reserve_packet_buffer();
4107     uint8_t * packet = hci_get_outgoing_packet_buffer();
4108 
4109     uint16_t size = 0;
4110     uint16_t num_handles = 0;
4111     packet[size++] = 0x35;
4112     packet[size++] = 0x0c;
4113     size++;  // skip param len
4114     size++;  // skip num handles
4115 
4116     // add { handle, packets } entries
4117     btstack_linked_item_t * it;
4118     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4119         hci_connection_t * connection = (hci_connection_t *) it;
4120         if (connection->num_packets_completed){
4121             little_endian_store_16(packet, size, connection->con_handle);
4122             size += 2;
4123             little_endian_store_16(packet, size, connection->num_packets_completed);
4124             size += 2;
4125             //
4126             num_handles++;
4127             connection->num_packets_completed = 0;
4128         }
4129     }
4130 
4131     packet[2] = size - 3;
4132     packet[3] = num_handles;
4133 
4134     hci_stack->host_completed_packets = 0;
4135 
4136     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4137     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4138 
4139     // release packet buffer for synchronous transport implementations
4140     if (hci_transport_synchronous()){
4141         hci_release_packet_buffer();
4142         hci_emit_transport_packet_sent();
4143     }
4144 }
4145 #endif
4146 
4147 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4148     UNUSED(ds);
4149     hci_stack->substate = HCI_HALTING_CLOSE;
4150     // allow packet handlers to defer final shutdown
4151     hci_emit_state();
4152     hci_run();
4153 }
4154 
4155 static bool hci_run_acl_fragments(void){
4156     if (hci_stack->acl_fragmentation_total_size > 0u) {
4157         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4158         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4159         if (connection) {
4160             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4161                 hci_send_acl_packet_fragments(connection);
4162                 return true;
4163             }
4164         } else {
4165             // connection gone -> discard further fragments
4166             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4167             hci_stack->acl_fragmentation_total_size = 0;
4168             hci_stack->acl_fragmentation_pos = 0;
4169         }
4170     }
4171     return false;
4172 }
4173 
4174 #ifdef ENABLE_CLASSIC
4175 static bool hci_run_general_gap_classic(void){
4176 
4177     // assert stack is working and classic is active
4178     if (hci_classic_supported() == false)      return false;
4179     if (hci_stack->state != HCI_STATE_WORKING) return false;
4180 
4181     // decline incoming connections
4182     if (hci_stack->decline_reason){
4183         uint8_t reason = hci_stack->decline_reason;
4184         hci_stack->decline_reason = 0;
4185         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4186         return true;
4187     }
4188 
4189     if (hci_stack->gap_tasks != 0){
4190         hci_run_gap_tasks_classic();
4191         return true;
4192     }
4193 
4194     // start/stop inquiry
4195     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4196         uint8_t duration = hci_stack->inquiry_state;
4197         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4198         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4199         return true;
4200     }
4201     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4202         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4203         hci_send_cmd(&hci_inquiry_cancel);
4204         return true;
4205     }
4206     // remote name request
4207     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4208         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4209         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4210                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4211         return true;
4212     }
4213 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4214     // Local OOB data
4215     if (hci_stack->classic_read_local_oob_data){
4216         hci_stack->classic_read_local_oob_data = false;
4217         if (hci_stack->local_supported_commands[1] & 0x10u){
4218             hci_send_cmd(&hci_read_local_extended_oob_data);
4219         } else {
4220             hci_send_cmd(&hci_read_local_oob_data);
4221         }
4222     }
4223 #endif
4224     // pairing
4225     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4226         uint8_t state = hci_stack->gap_pairing_state;
4227         uint8_t pin_code[16];
4228         switch (state){
4229             case GAP_PAIRING_STATE_SEND_PIN:
4230                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4231                 memset(pin_code, 0, 16);
4232                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4233                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4234                 break;
4235             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4236                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4237                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4238                 break;
4239             case GAP_PAIRING_STATE_SEND_PASSKEY:
4240                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4241                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4242                 break;
4243             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4244                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4245                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4246                 break;
4247             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4248                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4249                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4250                 break;
4251             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4252                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4253                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4254                 break;
4255             default:
4256                 break;
4257         }
4258         return true;
4259     }
4260     return false;
4261 }
4262 #endif
4263 
4264 #ifdef ENABLE_BLE
4265 static bool hci_run_general_gap_le(void){
4266 
4267     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4268 
4269     if (hci_stack->state != HCI_STATE_WORKING) return false;
4270     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4271 
4272 
4273     // Phase 1: collect what to stop
4274 
4275     bool scanning_stop = false;
4276     bool connecting_stop = false;
4277     bool advertising_stop = false;
4278 
4279 #ifndef ENABLE_LE_CENTRAL
4280     UNUSED(scanning_stop);
4281     UNUSED(connecting_stop);
4282 #endif
4283 #ifndef ENABLE_LE_PERIPHERAL
4284     UNUSED(advertising_stop);
4285 #endif
4286 
4287     // check if whitelist needs modification
4288     bool whitelist_modification_pending = false;
4289     btstack_linked_list_iterator_t lit;
4290     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4291     while (btstack_linked_list_iterator_has_next(&lit)){
4292         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4293         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4294             whitelist_modification_pending = true;
4295             break;
4296         }
4297     }
4298     // check if resolving list needs modification
4299     bool resolving_list_modification_pending = false;
4300 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4301     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4302 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4303         resolving_list_modification_pending = true;
4304     }
4305 #endif
4306 
4307 #ifdef ENABLE_LE_CENTRAL
4308     // scanning control
4309     if (hci_stack->le_scanning_active) {
4310         // stop if:
4311         // - parameter change required
4312         // - it's disabled
4313         // - whitelist change required but used for scanning
4314         // - resolving list modified
4315         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4316         if ((hci_stack->le_scanning_param_update) ||
4317             !hci_stack->le_scanning_enabled ||
4318             scanning_uses_whitelist ||
4319             resolving_list_modification_pending){
4320 
4321             scanning_stop = true;
4322         }
4323     }
4324 #endif
4325 
4326 #ifdef ENABLE_LE_CENTRAL
4327     // connecting control
4328     bool connecting_with_whitelist;
4329     switch (hci_stack->le_connecting_state){
4330         case LE_CONNECTING_DIRECT:
4331         case LE_CONNECTING_WHITELIST:
4332             // stop connecting if:
4333             // - connecting uses white and whitelist modification pending
4334             // - if it got disabled
4335             // - resolving list modified
4336             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4337             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4338                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4339                 resolving_list_modification_pending) {
4340 
4341                 connecting_stop = true;
4342             }
4343             break;
4344         default:
4345             break;
4346     }
4347 #endif
4348 
4349 #ifdef ENABLE_LE_PERIPHERAL
4350     // le advertisement control
4351     if (hci_stack->le_advertisements_active){
4352         // stop if:
4353         // - parameter change required
4354         // - it's disabled
4355         // - whitelist change required but used for advertisement filter policy
4356         // - resolving list modified
4357         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4358         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4359         if (advertising_change ||
4360             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4361             (advertising_uses_whitelist & whitelist_modification_pending) ||
4362             resolving_list_modification_pending) {
4363 
4364             advertising_stop = true;
4365         }
4366     }
4367 #endif
4368 
4369 
4370     // Phase 2: stop everything that should be off during modifications
4371 
4372 #ifdef ENABLE_LE_CENTRAL
4373     if (scanning_stop){
4374         hci_stack->le_scanning_active = false;
4375         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4376         return true;
4377     }
4378 #endif
4379 
4380 #ifdef ENABLE_LE_CENTRAL
4381     if (connecting_stop){
4382         hci_send_cmd(&hci_le_create_connection_cancel);
4383         return true;
4384     }
4385 #endif
4386 
4387 #ifdef ENABLE_LE_PERIPHERAL
4388     if (advertising_stop){
4389         hci_stack->le_advertisements_active = false;
4390         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4391         return true;
4392     }
4393 #endif
4394 
4395     // Phase 3: modify
4396 
4397 #ifdef ENABLE_LE_CENTRAL
4398     if (hci_stack->le_scanning_param_update){
4399         hci_stack->le_scanning_param_update = false;
4400         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4401                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4402         return true;
4403     }
4404 #endif
4405 
4406 #ifdef ENABLE_LE_PERIPHERAL
4407     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4408         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4409         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4410         hci_send_cmd(&hci_le_set_advertising_parameters,
4411                      hci_stack->le_advertisements_interval_min,
4412                      hci_stack->le_advertisements_interval_max,
4413                      hci_stack->le_advertisements_type,
4414                      hci_stack->le_advertisements_own_addr_type,
4415                      hci_stack->le_advertisements_direct_address_type,
4416                      hci_stack->le_advertisements_direct_address,
4417                      hci_stack->le_advertisements_channel_map,
4418                      hci_stack->le_advertisements_filter_policy);
4419         return true;
4420     }
4421     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4422         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4423         uint8_t adv_data_clean[31];
4424         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4425         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4426                      hci_stack->le_advertisements_data_len);
4427         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4428         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4429         return true;
4430     }
4431     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4432         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4433         uint8_t scan_data_clean[31];
4434         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4435         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4436                      hci_stack->le_scan_response_data_len);
4437         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4438         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4439         return true;
4440     }
4441 #endif
4442 
4443 
4444 #ifdef ENABLE_LE_CENTRAL
4445     // if connect with whitelist was active and is not cancelled yet, wait until next time
4446     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4447 #endif
4448 
4449     // LE Whitelist Management
4450     if (whitelist_modification_pending){
4451         // add/remove entries
4452         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4453         while (btstack_linked_list_iterator_has_next(&lit)){
4454             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4455 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4456 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4457 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4458 				return true;
4459 			}
4460             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4461 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4462                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4463                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4464                 return true;
4465             }
4466             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4467 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4468 				btstack_memory_whitelist_entry_free(entry);
4469             }
4470         }
4471     }
4472 
4473 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4474     // LE Resolving List Management
4475     if (resolving_list_supported) {
4476 		uint16_t i;
4477 		switch (hci_stack->le_resolving_list_state) {
4478 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4479 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4480 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4481 				return true;
4482 			case LE_RESOLVING_LIST_READ_SIZE:
4483 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4484 				hci_send_cmd(&hci_le_read_resolving_list_size);
4485 				return true;
4486 			case LE_RESOLVING_LIST_SEND_CLEAR:
4487 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4488 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4489 							  sizeof(hci_stack->le_resolving_list_add_entries));
4490 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4491 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4492 				hci_send_cmd(&hci_le_clear_resolving_list);
4493 				return true;
4494 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4495 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4496 					uint8_t offset = i >> 3;
4497 					uint8_t mask = 1 << (i & 7);
4498 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4499 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4500 					bd_addr_t peer_identity_addreses;
4501 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4502 					sm_key_t peer_irk;
4503 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4504 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4505 
4506 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4507 					// trigger whitelist entry 'update' (work around for controller bug)
4508 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4509 					while (btstack_linked_list_iterator_has_next(&lit)) {
4510 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4511 						if (entry->address_type != peer_identity_addr_type) continue;
4512 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4513 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4514 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4515 					}
4516 #endif
4517 
4518 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4519 								 peer_identity_addreses);
4520 					return true;
4521 				}
4522 
4523 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4524 
4525 				/* fall through */
4526 
4527 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4528 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4529 					uint8_t offset = i >> 3;
4530 					uint8_t mask = 1 << (i & 7);
4531 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4532 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4533 					bd_addr_t peer_identity_addreses;
4534 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4535 					sm_key_t peer_irk;
4536 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4537 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4538 					const uint8_t *local_irk = gap_get_persistent_irk();
4539 					// command uses format specifier 'P' that stores 16-byte value without flip
4540 					uint8_t local_irk_flipped[16];
4541 					uint8_t peer_irk_flipped[16];
4542 					reverse_128(local_irk, local_irk_flipped);
4543 					reverse_128(peer_irk, peer_irk_flipped);
4544 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4545 								 peer_irk_flipped, local_irk_flipped);
4546 					return true;
4547 				}
4548 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4549 				break;
4550 
4551 			default:
4552 				break;
4553 		}
4554 	}
4555     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4556 #endif
4557 
4558     // Phase 4: restore state
4559 
4560 #ifdef ENABLE_LE_CENTRAL
4561     // re-start scanning
4562     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4563         hci_stack->le_scanning_active = true;
4564         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4565         return true;
4566     }
4567 #endif
4568 
4569 #ifdef ENABLE_LE_CENTRAL
4570     // re-start connecting
4571     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4572         bd_addr_t null_addr;
4573         memset(null_addr, 0, 6);
4574         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4575         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4576         hci_send_cmd(&hci_le_create_connection,
4577                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4578                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4579                      1,         // use whitelist
4580                      0,         // peer address type
4581                      null_addr, // peer bd addr
4582                      hci_stack->le_connection_own_addr_type,   // our addr type:
4583                      hci_stack->le_connection_interval_min,    // conn interval min
4584                      hci_stack->le_connection_interval_max,    // conn interval max
4585                      hci_stack->le_connection_latency,         // conn latency
4586                      hci_stack->le_supervision_timeout,        // conn latency
4587                      hci_stack->le_minimum_ce_length,          // min ce length
4588                      hci_stack->le_maximum_ce_length           // max ce length
4589         );
4590         return true;
4591     }
4592 #endif
4593 
4594 #ifdef ENABLE_LE_PERIPHERAL
4595     // re-start advertising
4596     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4597         // check if advertisements should be enabled given
4598         hci_stack->le_advertisements_active = true;
4599         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4600         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4601         return true;
4602     }
4603 #endif
4604 
4605     return false;
4606 }
4607 #endif
4608 
4609 static bool hci_run_general_pending_commands(void){
4610     btstack_linked_item_t * it;
4611     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4612         hci_connection_t * connection = (hci_connection_t *) it;
4613 
4614         switch(connection->state){
4615             case SEND_CREATE_CONNECTION:
4616                 switch(connection->address_type){
4617 #ifdef ENABLE_CLASSIC
4618                     case BD_ADDR_TYPE_ACL:
4619                         log_info("sending hci_create_connection");
4620                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4621                         break;
4622 #endif
4623                     default:
4624 #ifdef ENABLE_BLE
4625 #ifdef ENABLE_LE_CENTRAL
4626                         log_info("sending hci_le_create_connection");
4627                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4628                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4629                         hci_send_cmd(&hci_le_create_connection,
4630                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4631                                      hci_stack->le_connection_scan_window,      // conn scan windows
4632                                      0,         // don't use whitelist
4633                                      connection->address_type, // peer address type
4634                                      connection->address,      // peer bd addr
4635                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4636                                      hci_stack->le_connection_interval_min,    // conn interval min
4637                                      hci_stack->le_connection_interval_max,    // conn interval max
4638                                      hci_stack->le_connection_latency,         // conn latency
4639                                      hci_stack->le_supervision_timeout,        // conn latency
4640                                      hci_stack->le_minimum_ce_length,          // min ce length
4641                                      hci_stack->le_maximum_ce_length          // max ce length
4642                         );
4643                         connection->state = SENT_CREATE_CONNECTION;
4644 #endif
4645 #endif
4646                         break;
4647                 }
4648                 return true;
4649 
4650 #ifdef ENABLE_CLASSIC
4651             case RECEIVED_CONNECTION_REQUEST:
4652                 connection->role  = HCI_ROLE_SLAVE;
4653                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4654                     log_info("sending hci_accept_connection_request");
4655                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4656                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4657                 }
4658                 return true;
4659 #endif
4660 
4661 #ifdef ENABLE_BLE
4662 #ifdef ENABLE_LE_CENTRAL
4663             case SEND_CANCEL_CONNECTION:
4664                 connection->state = SENT_CANCEL_CONNECTION;
4665                 hci_send_cmd(&hci_le_create_connection_cancel);
4666                 return true;
4667 #endif
4668 #endif
4669             case SEND_DISCONNECT:
4670                 connection->state = SENT_DISCONNECT;
4671                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4672                 return true;
4673 
4674             default:
4675                 break;
4676         }
4677 
4678         // no further commands if connection is about to get shut down
4679         if (connection->state == SENT_DISCONNECT) continue;
4680 
4681         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4682             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4683             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4684             return true;
4685         }
4686 
4687 #ifdef ENABLE_CLASSIC
4688 
4689         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4690             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4691             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4692             return true;
4693         }
4694 
4695         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4696             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4697             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4698             return true;
4699         }
4700 
4701         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4702             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4703             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4704             return true;
4705         }
4706 
4707         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4708             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4709             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4710             return true;
4711         }
4712 
4713         // Handling link key request requires remote supported features
4714         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4715             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4716             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4717 
4718             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4719             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4720             if (have_link_key && security_level_sufficient){
4721                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4722             } else {
4723                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4724             }
4725             return true;
4726         }
4727 
4728         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4729             log_info("denying to pin request");
4730             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4731             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4732             return true;
4733         }
4734 
4735         // security assessment requires remote features
4736         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4737             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4738             hci_ssp_assess_security_on_io_cap_request(connection);
4739             // 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
4740         }
4741 
4742         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4743             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4744             // set authentication requirements:
4745             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4746             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4747             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4748             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4749                 authreq |= 1;
4750             }
4751             bool bonding = hci_stack->bondable;
4752             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4753                 // if we have received IO Cap Response, we're in responder role
4754                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4755                 if (bonding && !remote_bonding){
4756                     log_info("Remote not bonding, dropping local flag");
4757                     bonding = false;
4758                 }
4759             }
4760             if (bonding){
4761                 if (connection->bonding_flags & BONDING_DEDICATED){
4762                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4763                 } else {
4764                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4765                 }
4766             }
4767             uint8_t have_oob_data = 0;
4768 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4769             if (connection->classic_oob_c_192 != NULL){
4770                     have_oob_data |= 1;
4771             }
4772             if (connection->classic_oob_c_256 != NULL){
4773                 have_oob_data |= 2;
4774             }
4775 #endif
4776             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4777             return true;
4778         }
4779 
4780         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4781             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4782             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4783             return true;
4784         }
4785 
4786 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4787         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4788             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4789             const uint8_t zero[16] = { 0 };
4790             const uint8_t * r_192 = zero;
4791             const uint8_t * c_192 = zero;
4792             const uint8_t * r_256 = zero;
4793             const uint8_t * c_256 = zero;
4794             // verify P-256 OOB
4795             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4796                 c_256 = connection->classic_oob_c_256;
4797                 if (connection->classic_oob_r_256 != NULL) {
4798                     r_256 = connection->classic_oob_r_256;
4799                 }
4800             }
4801             // verify P-192 OOB
4802             if ((connection->classic_oob_c_192 != NULL)) {
4803                 c_192 = connection->classic_oob_c_192;
4804                 if (connection->classic_oob_r_192 != NULL) {
4805                     r_192 = connection->classic_oob_r_192;
4806                 }
4807             }
4808 
4809             // assess security
4810             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4811             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4812             if (need_level_4 && !can_reach_level_4){
4813                 log_info("Level 4 required, but not possible -> abort");
4814                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4815                 // send oob negative reply
4816                 c_256 = NULL;
4817                 c_192 = NULL;
4818             }
4819 
4820             // Reply
4821             if (c_256 != zero) {
4822                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4823             } else if (c_192 != zero){
4824                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4825             } else {
4826                 hci_stack->classic_oob_con_handle = connection->con_handle;
4827                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4828             }
4829             return true;
4830         }
4831 #endif
4832 
4833         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4834             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4835             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4836             return true;
4837         }
4838 
4839         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4840             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4841             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4842             return true;
4843         }
4844 
4845         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4846             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4847             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4848             return true;
4849         }
4850 
4851         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4852             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4853             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4854             connection->state = SENT_DISCONNECT;
4855             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4856             return true;
4857         }
4858 
4859         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4860             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4861             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4862             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4863             return true;
4864         }
4865 
4866         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4867             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4868             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4869             return true;
4870         }
4871         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4872             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4873             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4874             return true;
4875         }
4876 #endif
4877 
4878         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4879             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4880 #ifdef ENABLE_CLASSIC
4881             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4882 #endif
4883             if (connection->state != SENT_DISCONNECT){
4884                 connection->state = SENT_DISCONNECT;
4885                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4886                 return true;
4887             }
4888         }
4889 
4890 #ifdef ENABLE_CLASSIC
4891         uint16_t sniff_min_interval;
4892         switch (connection->sniff_min_interval){
4893             case 0:
4894                 break;
4895             case 0xffff:
4896                 connection->sniff_min_interval = 0;
4897                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4898                 return true;
4899             default:
4900                 sniff_min_interval = connection->sniff_min_interval;
4901                 connection->sniff_min_interval = 0;
4902                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4903                 return true;
4904         }
4905 
4906         if (connection->sniff_subrating_max_latency != 0xffff){
4907             uint16_t max_latency = connection->sniff_subrating_max_latency;
4908             connection->sniff_subrating_max_latency = 0;
4909             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4910             return true;
4911         }
4912 
4913         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4914             uint8_t service_type = (uint8_t) connection->qos_service_type;
4915             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4916             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);
4917             return true;
4918         }
4919 
4920         if (connection->request_role != HCI_ROLE_INVALID){
4921             hci_role_t role = connection->request_role;
4922             connection->request_role = HCI_ROLE_INVALID;
4923             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4924             return true;
4925         }
4926 #endif
4927 
4928 #ifdef ENABLE_BLE
4929         switch (connection->le_con_parameter_update_state){
4930             // response to L2CAP CON PARAMETER UPDATE REQUEST
4931             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4932                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4933                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4934                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4935                              0x0000, 0xffff);
4936                 return true;
4937             case CON_PARAMETER_UPDATE_REPLY:
4938                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4939                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4940                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4941                              0x0000, 0xffff);
4942                 return true;
4943             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4944                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4945                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4946                 return true;
4947             default:
4948                 break;
4949         }
4950         if (connection->le_phy_update_all_phys != 0xffu){
4951             uint8_t all_phys = connection->le_phy_update_all_phys;
4952             connection->le_phy_update_all_phys = 0xff;
4953             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);
4954             return true;
4955         }
4956 #endif
4957     }
4958     return false;
4959 }
4960 
4961 static void hci_run(void){
4962 
4963     bool done;
4964 
4965     // send continuation fragments first, as they block the prepared packet buffer
4966     done = hci_run_acl_fragments();
4967     if (done) return;
4968 
4969 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4970     // send host num completed packets next as they don't require num_cmd_packets > 0
4971     if (!hci_can_send_comand_packet_transport()) return;
4972     if (hci_stack->host_completed_packets){
4973         hci_host_num_completed_packets();
4974         return;
4975     }
4976 #endif
4977 
4978     if (!hci_can_send_command_packet_now()) return;
4979 
4980     // global/non-connection oriented commands
4981 
4982 
4983 #ifdef ENABLE_CLASSIC
4984     // general gap classic
4985     done = hci_run_general_gap_classic();
4986     if (done) return;
4987 #endif
4988 
4989 #ifdef ENABLE_BLE
4990     // general gap le
4991     done = hci_run_general_gap_le();
4992     if (done) return;
4993 #endif
4994 
4995     // send pending HCI commands
4996     done = hci_run_general_pending_commands();
4997     if (done) return;
4998 
4999     // stack state sub statemachines
5000     hci_connection_t * connection;
5001     switch (hci_stack->state){
5002         case HCI_STATE_INITIALIZING:
5003             hci_initializing_run();
5004             break;
5005 
5006         case HCI_STATE_HALTING:
5007 
5008             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5009             switch (hci_stack->substate){
5010                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5011                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5012 
5013 #ifdef ENABLE_BLE
5014 #ifdef ENABLE_LE_CENTRAL
5015                     // free whitelist entries
5016                     {
5017                         btstack_linked_list_iterator_t lit;
5018                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5019                         while (btstack_linked_list_iterator_has_next(&lit)){
5020                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5021                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5022                             btstack_memory_whitelist_entry_free(entry);
5023                         }
5024                     }
5025 #endif
5026 #endif
5027                     // close all open connections
5028                     connection =  (hci_connection_t *) hci_stack->connections;
5029                     if (connection){
5030                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5031                         if (!hci_can_send_command_packet_now()) return;
5032 
5033                         // check state
5034                         if (connection->state == SENT_DISCONNECT) return;
5035                         connection->state = SENT_DISCONNECT;
5036 
5037                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5038 
5039                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5040                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5041 
5042                         // ... which would be ignored anyway as we shutdown (free) the connection now
5043                         hci_shutdown_connection(connection);
5044 
5045                         // finally, send the disconnect command
5046                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5047                         return;
5048                     }
5049 
5050                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5051                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5052                         log_info("HCI_STATE_HALTING: wait 50 ms");
5053                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5054                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5055                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5056                         btstack_run_loop_add_timer(&hci_stack->timeout);
5057                         break;
5058                     }
5059 
5060                     /* fall through */
5061 
5062                 case HCI_HALTING_CLOSE:
5063                     log_info("HCI_STATE_HALTING, calling off");
5064 
5065                     // switch mode
5066                     hci_power_control_off();
5067 
5068                     log_info("HCI_STATE_HALTING, emitting state");
5069                     hci_emit_state();
5070                     log_info("HCI_STATE_HALTING, done");
5071                     break;
5072 
5073                 case HCI_HALTING_W4_TIMER:
5074                     // keep waiting
5075 
5076                     break;
5077                 default:
5078                     break;
5079             }
5080 
5081             break;
5082 
5083         case HCI_STATE_FALLING_ASLEEP:
5084             switch(hci_stack->substate) {
5085                 case HCI_FALLING_ASLEEP_DISCONNECT:
5086                     log_info("HCI_STATE_FALLING_ASLEEP");
5087                     // close all open connections
5088                     connection =  (hci_connection_t *) hci_stack->connections;
5089                     if (connection){
5090 
5091                         // send disconnect
5092                         if (!hci_can_send_command_packet_now()) return;
5093 
5094                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5095                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5096 
5097                         // send disconnected event right away - causes higher layer connections to get closed, too.
5098                         hci_shutdown_connection(connection);
5099                         return;
5100                     }
5101 
5102                     if (hci_classic_supported()){
5103                         // disable page and inquiry scan
5104                         if (!hci_can_send_command_packet_now()) return;
5105 
5106                         log_info("HCI_STATE_HALTING, disabling inq scans");
5107                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5108 
5109                         // continue in next sub state
5110                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5111                         break;
5112                     }
5113 
5114                     /* fall through */
5115 
5116                 case HCI_FALLING_ASLEEP_COMPLETE:
5117                     log_info("HCI_STATE_HALTING, calling sleep");
5118                     // switch mode
5119                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5120                     hci_emit_state();
5121                     break;
5122 
5123                 default:
5124                     break;
5125             }
5126             break;
5127 
5128         default:
5129             break;
5130     }
5131 }
5132 
5133 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5134     // house-keeping
5135 
5136 #ifdef ENABLE_CLASSIC
5137     bd_addr_t addr;
5138     hci_connection_t * conn;
5139 #endif
5140 #ifdef ENABLE_LE_CENTRAL
5141     uint8_t initiator_filter_policy;
5142 #endif
5143 
5144     uint16_t opcode = little_endian_read_16(packet, 0);
5145     switch (opcode) {
5146         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5147             hci_stack->loopback_mode = packet[3];
5148             break;
5149 
5150 #ifdef ENABLE_CLASSIC
5151         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5152             reverse_bd_addr(&packet[3], addr);
5153             log_info("Create_connection to %s", bd_addr_to_str(addr));
5154 
5155             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5156             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5157                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5158                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5159             }
5160 
5161             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5162             if (!conn) {
5163                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5164                 if (!conn) {
5165                     // notify client that alloc failed
5166                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5167                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5168                 }
5169                 conn->state = SEND_CREATE_CONNECTION;
5170                 conn->role  = HCI_ROLE_MASTER;
5171             }
5172 
5173             conn->con_handle = HCI_CON_HANDLE_INVALID;
5174             conn->role = HCI_ROLE_INVALID;
5175 
5176             log_info("conn state %u", conn->state);
5177             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5178             switch (conn->state) {
5179                 // if connection active exists
5180                 case OPEN:
5181                     // and OPEN, emit connection complete command
5182                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5183                     // packet not sent to controller
5184                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5185                 case RECEIVED_DISCONNECTION_COMPLETE:
5186                     // create connection triggered in disconnect complete event, let's do it now
5187                     break;
5188                 case SEND_CREATE_CONNECTION:
5189                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5190                     break;
5191                 default:
5192                     // otherwise, just ignore as it is already in the open process
5193                     // packet not sent to controller
5194                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5195             }
5196             conn->state = SENT_CREATE_CONNECTION;
5197 
5198             // track outgoing connection
5199             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5200             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5201             break;
5202         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5203             if (hci_stack->link_key_db) {
5204                 reverse_bd_addr(&packet[3], addr);
5205                 hci_stack->link_key_db->delete_link_key(addr);
5206             }
5207             break;
5208 
5209 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5210         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5211             // setup_synchronous_connection? Voice setting at offset 22
5212             // TODO: compare to current setting if sco connection already active
5213             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5214             break;
5215         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5216             // accept_synchronus_connection? Voice setting at offset 18
5217             // TODO: compare to current setting if sco connection already active
5218             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5219             break;
5220 #endif
5221 #endif
5222 
5223 #ifdef ENABLE_BLE
5224         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5225             hci_stack->le_random_address_set = 1;
5226             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5227             break;
5228 #ifdef ENABLE_LE_PERIPHERAL
5229         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5230             hci_stack->le_advertisements_active = packet[3] != 0;
5231             break;
5232 #endif
5233 #ifdef ENABLE_LE_CENTRAL
5234         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5235             // white list used?
5236             initiator_filter_policy = packet[7];
5237             switch (initiator_filter_policy) {
5238                 case 0:
5239                     // whitelist not used
5240                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5241                     break;
5242                 case 1:
5243                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5244                     break;
5245                 default:
5246                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5247                     break;
5248             }
5249             // track outgoing connection
5250             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5251             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5252             break;
5253         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5254             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5255             break;
5256 #endif
5257 #endif
5258         default:
5259             break;
5260     }
5261 
5262     hci_stack->num_cmd_packets--;
5263 
5264     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5265     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5266     if (err != 0){
5267         return ERROR_CODE_HARDWARE_FAILURE;
5268     }
5269     return ERROR_CODE_SUCCESS;
5270 }
5271 
5272 // disconnect because of security block
5273 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5274     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5275     if (!connection) return;
5276     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5277 }
5278 
5279 
5280 // Configure Secure Simple Pairing
5281 
5282 #ifdef ENABLE_CLASSIC
5283 
5284 // enable will enable SSP during init
5285 void gap_ssp_set_enable(int enable){
5286     hci_stack->ssp_enable = enable;
5287 }
5288 
5289 static int hci_local_ssp_activated(void){
5290     return gap_ssp_supported() && hci_stack->ssp_enable;
5291 }
5292 
5293 // if set, BTstack will respond to io capability request using authentication requirement
5294 void gap_ssp_set_io_capability(int io_capability){
5295     hci_stack->ssp_io_capability = io_capability;
5296 }
5297 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5298     hci_stack->ssp_authentication_requirement = authentication_requirement;
5299 }
5300 
5301 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5302 void gap_ssp_set_auto_accept(int auto_accept){
5303     hci_stack->ssp_auto_accept = auto_accept;
5304 }
5305 
5306 void gap_secure_connections_enable(bool enable){
5307     hci_stack->secure_connections_enable = enable;
5308 }
5309 
5310 #endif
5311 
5312 // va_list part of hci_send_cmd
5313 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5314     if (!hci_can_send_command_packet_now()){
5315         log_error("hci_send_cmd called but cannot send packet now");
5316         return ERROR_CODE_COMMAND_DISALLOWED;
5317     }
5318 
5319     // for HCI INITIALIZATION
5320     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5321     hci_stack->last_cmd_opcode = cmd->opcode;
5322 
5323     hci_reserve_packet_buffer();
5324     uint8_t * packet = hci_stack->hci_packet_buffer;
5325     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5326     uint8_t status = hci_send_cmd_packet(packet, size);
5327 
5328     // release packet buffer on error or for synchronous transport implementations
5329     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5330         hci_release_packet_buffer();
5331         hci_emit_transport_packet_sent();
5332     }
5333 
5334     return status;
5335 }
5336 
5337 /**
5338  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5339  */
5340 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5341     va_list argptr;
5342     va_start(argptr, cmd);
5343     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5344     va_end(argptr);
5345     return status;
5346 }
5347 
5348 // Create various non-HCI events.
5349 // TODO: generalize, use table similar to hci_create_command
5350 
5351 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5352     // dump packet
5353     if (dump) {
5354         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5355     }
5356 
5357     // dispatch to all event handlers
5358     btstack_linked_list_iterator_t it;
5359     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5360     while (btstack_linked_list_iterator_has_next(&it)){
5361         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5362         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5363     }
5364 }
5365 
5366 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5367     if (!hci_stack->acl_packet_handler) return;
5368     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5369 }
5370 
5371 #ifdef ENABLE_CLASSIC
5372 static void hci_notify_if_sco_can_send_now(void){
5373     // notify SCO sender if waiting
5374     if (!hci_stack->sco_waiting_for_can_send_now) return;
5375     if (hci_can_send_sco_packet_now()){
5376         hci_stack->sco_waiting_for_can_send_now = 0;
5377         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5378         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5379         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5380     }
5381 }
5382 
5383 // parsing end emitting has been merged to reduce code size
5384 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5385     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5386 
5387     uint8_t * eir_data;
5388     ad_context_t context;
5389     const uint8_t * name;
5390     uint8_t         name_len;
5391 
5392     if (size < 3) return;
5393 
5394     int event_type = hci_event_packet_get_type(packet);
5395     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5396     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5397 
5398     switch (event_type){
5399         case HCI_EVENT_INQUIRY_RESULT:
5400         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5401             if (size != (3 + (num_responses * 14))) return;
5402             break;
5403         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5404             if (size != 257) return;
5405             if (num_responses != 1) return;
5406             break;
5407         default:
5408             return;
5409     }
5410 
5411     // event[1] is set at the end
5412     int i;
5413     for (i=0; i<num_responses;i++){
5414         memset(event, 0, sizeof(event));
5415         event[0] = GAP_EVENT_INQUIRY_RESULT;
5416         uint8_t event_size = 27;    // if name is not set by EIR
5417 
5418         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5419         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5420         (void)memcpy(&event[9],
5421                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5422                      3); // class of device
5423         (void)memcpy(&event[12],
5424                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5425                      2); // clock offset
5426 
5427         switch (event_type){
5428             case HCI_EVENT_INQUIRY_RESULT:
5429                 // 14,15,16,17 = 0, size 18
5430                 break;
5431             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5432                 event[14] = 1;
5433                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5434                 // 16,17 = 0, size 18
5435                 break;
5436             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5437                 event[14] = 1;
5438                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5439                 // EIR packets only contain a single inquiry response
5440                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5441                 name = NULL;
5442                 // Iterate over EIR data
5443                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5444                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5445                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5446                     const uint8_t * data = ad_iterator_get_data(&context);
5447                     // Prefer Complete Local Name over Shortened Local Name
5448                     switch (data_type){
5449                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5450                             if (name) continue;
5451                             /* fall through */
5452                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5453                             name = data;
5454                             name_len = data_size;
5455                             break;
5456                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5457                             if (data_size != 8) break;
5458                             event[16] = 1;
5459                             memcpy(&event[17], data, 8);
5460                             break;
5461                         default:
5462                             break;
5463                     }
5464                 }
5465                 if (name){
5466                     event[25] = 1;
5467                     // truncate name if needed
5468                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5469                     event[26] = len;
5470                     (void)memcpy(&event[27], name, len);
5471                     event_size += len;
5472                 }
5473                 break;
5474             default:
5475                 return;
5476         }
5477         event[1] = event_size - 2;
5478         hci_emit_event(event, event_size, 1);
5479     }
5480 }
5481 #endif
5482 
5483 void hci_emit_state(void){
5484     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5485     uint8_t event[3];
5486     event[0] = BTSTACK_EVENT_STATE;
5487     event[1] = sizeof(event) - 2u;
5488     event[2] = hci_stack->state;
5489     hci_emit_event(event, sizeof(event), 1);
5490 }
5491 
5492 #ifdef ENABLE_CLASSIC
5493 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5494     uint8_t event[13];
5495     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5496     event[1] = sizeof(event) - 2;
5497     event[2] = status;
5498     little_endian_store_16(event, 3, con_handle);
5499     reverse_bd_addr(address, &event[5]);
5500     event[11] = 1; // ACL connection
5501     event[12] = 0; // encryption disabled
5502     hci_emit_event(event, sizeof(event), 1);
5503 }
5504 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5505     if (disable_l2cap_timeouts) return;
5506     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5507     uint8_t event[4];
5508     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5509     event[1] = sizeof(event) - 2;
5510     little_endian_store_16(event, 2, conn->con_handle);
5511     hci_emit_event(event, sizeof(event), 1);
5512 }
5513 #endif
5514 
5515 #ifdef ENABLE_BLE
5516 #ifdef ENABLE_LE_CENTRAL
5517 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){
5518     uint8_t event[21];
5519     event[0] = HCI_EVENT_LE_META;
5520     event[1] = sizeof(event) - 2u;
5521     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5522     event[3] = status;
5523     little_endian_store_16(event, 4, con_handle);
5524     event[6] = 0; // TODO: role
5525     event[7] = address_type;
5526     reverse_bd_addr(address, &event[8]);
5527     little_endian_store_16(event, 14, 0); // interval
5528     little_endian_store_16(event, 16, 0); // latency
5529     little_endian_store_16(event, 18, 0); // supervision timeout
5530     event[20] = 0; // master clock accuracy
5531     hci_emit_event(event, sizeof(event), 1);
5532 }
5533 #endif
5534 #endif
5535 
5536 static void hci_emit_transport_packet_sent(void){
5537     // notify upper stack that it might be possible to send again
5538     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5539     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5540 }
5541 
5542 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5543     uint8_t event[6];
5544     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5545     event[1] = sizeof(event) - 2u;
5546     event[2] = 0; // status = OK
5547     little_endian_store_16(event, 3, con_handle);
5548     event[5] = reason;
5549     hci_emit_event(event, sizeof(event), 1);
5550 }
5551 
5552 static void hci_emit_nr_connections_changed(void){
5553     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5554     uint8_t event[3];
5555     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5556     event[1] = sizeof(event) - 2u;
5557     event[2] = nr_hci_connections();
5558     hci_emit_event(event, sizeof(event), 1);
5559 }
5560 
5561 static void hci_emit_hci_open_failed(void){
5562     log_info("BTSTACK_EVENT_POWERON_FAILED");
5563     uint8_t event[2];
5564     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5565     event[1] = sizeof(event) - 2u;
5566     hci_emit_event(event, sizeof(event), 1);
5567 }
5568 
5569 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5570     log_info("hci_emit_dedicated_bonding_result %u ", status);
5571     uint8_t event[9];
5572     int pos = 0;
5573     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5574     event[pos++] = sizeof(event) - 2u;
5575     event[pos++] = status;
5576     reverse_bd_addr(address, &event[pos]);
5577     hci_emit_event(event, sizeof(event), 1);
5578 }
5579 
5580 
5581 #ifdef ENABLE_CLASSIC
5582 
5583 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5584     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5585     uint8_t event[5];
5586     int pos = 0;
5587     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5588     event[pos++] = sizeof(event) - 2;
5589     little_endian_store_16(event, 2, con_handle);
5590     pos += 2;
5591     event[pos++] = level;
5592     hci_emit_event(event, sizeof(event), 1);
5593 }
5594 
5595 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5596     if (!connection) return LEVEL_0;
5597     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5598     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5599     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5600     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5601     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5602     // LEVEL 4 always requires 128 bit encrytion key size
5603     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5604         security_level = LEVEL_3;
5605     }
5606     return security_level;
5607 }
5608 
5609 static void hci_emit_discoverable_enabled(uint8_t enabled){
5610     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5611     uint8_t event[3];
5612     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5613     event[1] = sizeof(event) - 2;
5614     event[2] = enabled;
5615     hci_emit_event(event, sizeof(event), 1);
5616 }
5617 
5618 // query if remote side supports eSCO
5619 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5620     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5621     if (!connection) return false;
5622     return (connection->remote_supported_features[0] & 1) != 0;
5623 }
5624 
5625 static bool hci_ssp_supported(hci_connection_t * connection){
5626     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5627     return (connection->bonding_flags & mask) == mask;
5628 }
5629 
5630 // query if remote side supports SSP
5631 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5632     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5633     if (!connection) return false;
5634     return hci_ssp_supported(connection) ? 1 : 0;
5635 }
5636 
5637 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5638     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5639 }
5640 
5641 // GAP API
5642 /**
5643  * @bbrief enable/disable bonding. default is enabled
5644  * @praram enabled
5645  */
5646 void gap_set_bondable_mode(int enable){
5647     hci_stack->bondable = enable ? 1 : 0;
5648 }
5649 /**
5650  * @brief Get bondable mode.
5651  * @return 1 if bondable
5652  */
5653 int gap_get_bondable_mode(void){
5654     return hci_stack->bondable;
5655 }
5656 
5657 /**
5658  * @brief map link keys to security levels
5659  */
5660 gap_security_level_t gap_security_level_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             return LEVEL_4;
5664         case COMBINATION_KEY:
5665         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5666             return LEVEL_3;
5667         default:
5668             return LEVEL_2;
5669     }
5670 }
5671 
5672 /**
5673  * @brief map link keys to secure connection yes/no
5674  */
5675 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5676     switch (link_key_type){
5677         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5678         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5679             return 1;
5680         default:
5681             return 0;
5682     }
5683 }
5684 
5685 /**
5686  * @brief map link keys to authenticated
5687  */
5688 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5689     switch (link_key_type){
5690         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5691         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5692             return 1;
5693         default:
5694             return 0;
5695     }
5696 }
5697 
5698 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5699     log_info("gap_mitm_protection_required_for_security_level %u", level);
5700     return level > LEVEL_2;
5701 }
5702 
5703 /**
5704  * @brief get current security level
5705  */
5706 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5707     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5708     if (!connection) return LEVEL_0;
5709     return gap_security_level_for_connection(connection);
5710 }
5711 
5712 /**
5713  * @brief request connection to device to
5714  * @result GAP_AUTHENTICATION_RESULT
5715  */
5716 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5717     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5718     if (!connection){
5719         hci_emit_security_level(con_handle, LEVEL_0);
5720         return;
5721     }
5722 
5723     btstack_assert(hci_is_le_connection(connection) == false);
5724 
5725     // 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)
5726     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5727     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5728         requested_level = LEVEL_4;
5729     }
5730 
5731     gap_security_level_t current_level = gap_security_level(con_handle);
5732     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5733         requested_level, connection->requested_security_level, current_level);
5734 
5735     // authentication active if authentication request was sent or planned level > 0
5736     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5737     if (authentication_active){
5738         // authentication already active
5739         if (connection->requested_security_level < requested_level){
5740             // increase requested level as new level is higher
5741             // TODO: handle re-authentication when done
5742             connection->requested_security_level = requested_level;
5743         }
5744     } else {
5745         // no request active, notify if security sufficient
5746         if (requested_level <= current_level){
5747             hci_emit_security_level(con_handle, current_level);
5748             return;
5749         }
5750 
5751         // store request
5752         connection->requested_security_level = requested_level;
5753 
5754         // start to authenticate connection
5755         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5756         hci_run();
5757     }
5758 }
5759 
5760 /**
5761  * @brief start dedicated bonding with device. disconnect after bonding
5762  * @param device
5763  * @param request MITM protection
5764  * @result GAP_DEDICATED_BONDING_COMPLETE
5765  */
5766 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5767 
5768     // create connection state machine
5769     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5770 
5771     if (!connection){
5772         return BTSTACK_MEMORY_ALLOC_FAILED;
5773     }
5774 
5775     // delete linkn key
5776     gap_drop_link_key_for_bd_addr(device);
5777 
5778     // configure LEVEL_2/3, dedicated bonding
5779     connection->state = SEND_CREATE_CONNECTION;
5780     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5781     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5782     connection->bonding_flags = BONDING_DEDICATED;
5783 
5784     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5785 
5786     // handle: connnection failure (connection complete != ok)
5787     // handle: authentication failure
5788     // handle: disconnect on done
5789 
5790     hci_run();
5791 
5792     return 0;
5793 }
5794 
5795 void gap_set_local_name(const char * local_name){
5796     hci_stack->local_name = local_name;
5797     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5798     // also update EIR if not set by user
5799     if (hci_stack->eir_data == NULL){
5800         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5801     }
5802     hci_run();
5803 }
5804 #endif
5805 
5806 
5807 #ifdef ENABLE_BLE
5808 
5809 #ifdef ENABLE_LE_CENTRAL
5810 void gap_start_scan(void){
5811     hci_stack->le_scanning_enabled = true;
5812     hci_run();
5813 }
5814 
5815 void gap_stop_scan(void){
5816     hci_stack->le_scanning_enabled = false;
5817     hci_run();
5818 }
5819 
5820 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5821     hci_stack->le_scan_type          = scan_type;
5822     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5823     hci_stack->le_scan_interval      = scan_interval;
5824     hci_stack->le_scan_window        = scan_window;
5825     hci_stack->le_scanning_param_update = true;
5826     hci_run();
5827 }
5828 
5829 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5830     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5831 }
5832 
5833 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5834     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5835     if (!conn){
5836         // disallow if le connection is already outgoing
5837         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5838             log_error("le connection already active");
5839             return ERROR_CODE_COMMAND_DISALLOWED;
5840         }
5841 
5842         log_info("gap_connect: no connection exists yet, creating context");
5843         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5844         if (!conn){
5845             // notify client that alloc failed
5846             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5847             log_info("gap_connect: failed to alloc hci_connection_t");
5848             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5849         }
5850 
5851         // set le connecting state
5852         if (hci_is_le_connection_type(addr_type)){
5853             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5854         }
5855 
5856         conn->state = SEND_CREATE_CONNECTION;
5857         log_info("gap_connect: send create connection next");
5858         hci_run();
5859         return ERROR_CODE_SUCCESS;
5860     }
5861 
5862     if (!hci_is_le_connection(conn) ||
5863         (conn->state == SEND_CREATE_CONNECTION) ||
5864         (conn->state == SENT_CREATE_CONNECTION)) {
5865         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5866         log_error("gap_connect: classic connection or connect is already being created");
5867         return GATT_CLIENT_IN_WRONG_STATE;
5868     }
5869 
5870     // check if connection was just disconnected
5871     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5872         log_info("gap_connect: send create connection (again)");
5873         conn->state = SEND_CREATE_CONNECTION;
5874         hci_run();
5875         return ERROR_CODE_SUCCESS;
5876     }
5877 
5878     log_info("gap_connect: context exists with state %u", conn->state);
5879     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5880     hci_run();
5881     return ERROR_CODE_SUCCESS;
5882 }
5883 
5884 // @assumption: only a single outgoing LE Connection exists
5885 static hci_connection_t * gap_get_outgoing_connection(void){
5886     btstack_linked_item_t *it;
5887     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5888         hci_connection_t * conn = (hci_connection_t *) it;
5889         if (!hci_is_le_connection(conn)) continue;
5890         switch (conn->state){
5891             case SEND_CREATE_CONNECTION:
5892             case SENT_CREATE_CONNECTION:
5893             case SENT_CANCEL_CONNECTION:
5894                 return conn;
5895             default:
5896                 break;
5897         };
5898     }
5899     return NULL;
5900 }
5901 
5902 uint8_t gap_connect_cancel(void){
5903     hci_connection_t * conn = gap_get_outgoing_connection();
5904     if (!conn) return 0;
5905     switch (conn->state){
5906         case SEND_CREATE_CONNECTION:
5907             // skip sending create connection and emit event instead
5908             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5909             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5910             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5911             btstack_memory_hci_connection_free( conn );
5912             break;
5913         case SENT_CREATE_CONNECTION:
5914             // request to send cancel connection
5915             conn->state = SEND_CANCEL_CONNECTION;
5916             hci_run();
5917             break;
5918         default:
5919             break;
5920     }
5921     return 0;
5922 }
5923 #endif
5924 
5925 #ifdef ENABLE_LE_CENTRAL
5926 /**
5927  * @brief Set connection parameters for outgoing connections
5928  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5929  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5930  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5931  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5932  * @param conn_latency, default: 4
5933  * @param supervision_timeout (unit: 10ms), default: 720 ms
5934  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5935  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5936  */
5937 
5938 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5939     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5940     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5941     hci_stack->le_connection_scan_interval = conn_scan_interval;
5942     hci_stack->le_connection_scan_window = conn_scan_window;
5943     hci_stack->le_connection_interval_min = conn_interval_min;
5944     hci_stack->le_connection_interval_max = conn_interval_max;
5945     hci_stack->le_connection_latency = conn_latency;
5946     hci_stack->le_supervision_timeout = supervision_timeout;
5947     hci_stack->le_minimum_ce_length = min_ce_length;
5948     hci_stack->le_maximum_ce_length = max_ce_length;
5949 }
5950 #endif
5951 
5952 /**
5953  * @brief Updates the connection parameters for a given LE connection
5954  * @param handle
5955  * @param conn_interval_min (unit: 1.25ms)
5956  * @param conn_interval_max (unit: 1.25ms)
5957  * @param conn_latency
5958  * @param supervision_timeout (unit: 10ms)
5959  * @returns 0 if ok
5960  */
5961 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5962     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5963     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5964     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5965     connection->le_conn_interval_min = conn_interval_min;
5966     connection->le_conn_interval_max = conn_interval_max;
5967     connection->le_conn_latency = conn_latency;
5968     connection->le_supervision_timeout = supervision_timeout;
5969     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5970     hci_run();
5971     return 0;
5972 }
5973 
5974 /**
5975  * @brief Request an update of the connection parameter for a given LE connection
5976  * @param handle
5977  * @param conn_interval_min (unit: 1.25ms)
5978  * @param conn_interval_max (unit: 1.25ms)
5979  * @param conn_latency
5980  * @param supervision_timeout (unit: 10ms)
5981  * @returns 0 if ok
5982  */
5983 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5984     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5985     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5986     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5987     connection->le_conn_interval_min = conn_interval_min;
5988     connection->le_conn_interval_max = conn_interval_max;
5989     connection->le_conn_latency = conn_latency;
5990     connection->le_supervision_timeout = supervision_timeout;
5991     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5992     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5993     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5994     return 0;
5995 }
5996 
5997 #ifdef ENABLE_LE_PERIPHERAL
5998 
5999 /**
6000  * @brief Set Advertisement Data
6001  * @param advertising_data_length
6002  * @param advertising_data (max 31 octets)
6003  * @note data is not copied, pointer has to stay valid
6004  */
6005 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6006     hci_stack->le_advertisements_data_len = advertising_data_length;
6007     hci_stack->le_advertisements_data = advertising_data;
6008     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6009     hci_run();
6010 }
6011 
6012 /**
6013  * @brief Set Scan Response Data
6014  * @param advertising_data_length
6015  * @param advertising_data (max 31 octets)
6016  * @note data is not copied, pointer has to stay valid
6017  */
6018 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6019     hci_stack->le_scan_response_data_len = scan_response_data_length;
6020     hci_stack->le_scan_response_data = scan_response_data;
6021     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6022     hci_run();
6023 }
6024 
6025 /**
6026  * @brief Set Advertisement Parameters
6027  * @param adv_int_min
6028  * @param adv_int_max
6029  * @param adv_type
6030  * @param direct_address_type
6031  * @param direct_address
6032  * @param channel_map
6033  * @param filter_policy
6034  *
6035  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6036  */
6037  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6038     uint8_t direct_address_typ, bd_addr_t direct_address,
6039     uint8_t channel_map, uint8_t filter_policy) {
6040 
6041     hci_stack->le_advertisements_interval_min = adv_int_min;
6042     hci_stack->le_advertisements_interval_max = adv_int_max;
6043     hci_stack->le_advertisements_type = adv_type;
6044     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6045     hci_stack->le_advertisements_channel_map = channel_map;
6046     hci_stack->le_advertisements_filter_policy = filter_policy;
6047     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6048                  6);
6049 
6050     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6051     hci_run();
6052  }
6053 
6054 /**
6055  * @brief Enable/Disable Advertisements
6056  * @param enabled
6057  */
6058 void gap_advertisements_enable(int enabled){
6059     hci_stack->le_advertisements_enabled = enabled != 0;
6060     hci_update_advertisements_enabled_for_current_roles();
6061     hci_run();
6062 }
6063 
6064 #endif
6065 
6066 void hci_le_set_own_address_type(uint8_t own_address_type){
6067     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6068     if (own_address_type == hci_stack->le_own_addr_type) return;
6069     hci_stack->le_own_addr_type = own_address_type;
6070 
6071 #ifdef ENABLE_LE_PERIPHERAL
6072     // update advertisement parameters, too
6073     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6074     hci_run();
6075 #endif
6076 #ifdef ENABLE_LE_CENTRAL
6077     // note: we don't update scan parameters or modify ongoing connection attempts
6078 #endif
6079 }
6080 
6081 #endif
6082 
6083 uint8_t gap_disconnect(hci_con_handle_t handle){
6084     hci_connection_t * conn = hci_connection_for_handle(handle);
6085     if (!conn){
6086         hci_emit_disconnection_complete(handle, 0);
6087         return 0;
6088     }
6089     // ignore if already disconnected
6090     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6091         return 0;
6092     }
6093     conn->state = SEND_DISCONNECT;
6094     hci_run();
6095     return 0;
6096 }
6097 
6098 int gap_read_rssi(hci_con_handle_t con_handle){
6099     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6100     if (hci_connection == NULL) return 0;
6101     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6102     hci_run();
6103     return 1;
6104 }
6105 
6106 /**
6107  * @brief Get connection type
6108  * @param con_handle
6109  * @result connection_type
6110  */
6111 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6112     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6113     if (!conn) return GAP_CONNECTION_INVALID;
6114     switch (conn->address_type){
6115         case BD_ADDR_TYPE_LE_PUBLIC:
6116         case BD_ADDR_TYPE_LE_RANDOM:
6117             return GAP_CONNECTION_LE;
6118         case BD_ADDR_TYPE_SCO:
6119             return GAP_CONNECTION_SCO;
6120         case BD_ADDR_TYPE_ACL:
6121             return GAP_CONNECTION_ACL;
6122         default:
6123             return GAP_CONNECTION_INVALID;
6124     }
6125 }
6126 
6127 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6128     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6129     if (!conn) return HCI_ROLE_INVALID;
6130     return (hci_role_t) conn->role;
6131 }
6132 
6133 
6134 #ifdef ENABLE_CLASSIC
6135 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6136     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6137     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6138     conn->request_role = role;
6139     hci_run();
6140     return ERROR_CODE_SUCCESS;
6141 }
6142 #endif
6143 
6144 #ifdef ENABLE_BLE
6145 
6146 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){
6147     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6148     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6149 
6150     conn->le_phy_update_all_phys    = all_phys;
6151     conn->le_phy_update_tx_phys     = tx_phys;
6152     conn->le_phy_update_rx_phys     = rx_phys;
6153     conn->le_phy_update_phy_options = phy_options;
6154 
6155     hci_run();
6156 
6157     return 0;
6158 }
6159 
6160 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6161     // check if already in list
6162     btstack_linked_list_iterator_t it;
6163     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6164     while (btstack_linked_list_iterator_has_next(&it)) {
6165         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6166         if (entry->address_type != address_type) {
6167             continue;
6168         }
6169         if (memcmp(entry->address, address, 6) != 0) {
6170             continue;
6171         }
6172 		// disallow if already scheduled to add
6173 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6174 			return ERROR_CODE_COMMAND_DISALLOWED;
6175 		}
6176 		// still on controller, but scheduled to remove -> re-add
6177 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6178 		return ERROR_CODE_SUCCESS;
6179     }
6180     // alloc and add to list
6181     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6182     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6183     entry->address_type = address_type;
6184     (void)memcpy(entry->address, address, 6);
6185     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6186     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6187     return ERROR_CODE_SUCCESS;
6188 }
6189 
6190 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6191     btstack_linked_list_iterator_t it;
6192     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6193     while (btstack_linked_list_iterator_has_next(&it)){
6194         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6195         if (entry->address_type != address_type) {
6196             continue;
6197         }
6198         if (memcmp(entry->address, address, 6) != 0) {
6199             continue;
6200         }
6201         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6202             // remove from controller if already present
6203             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6204         }  else {
6205             // directly remove entry from whitelist
6206             btstack_linked_list_iterator_remove(&it);
6207             btstack_memory_whitelist_entry_free(entry);
6208         }
6209         return ERROR_CODE_SUCCESS;
6210     }
6211     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6212 }
6213 
6214 static void hci_whitelist_clear(void){
6215     btstack_linked_list_iterator_t it;
6216     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6217     while (btstack_linked_list_iterator_has_next(&it)){
6218         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6219         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6220             // remove from controller if already present
6221             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6222             continue;
6223         }
6224         // directly remove entry from whitelist
6225         btstack_linked_list_iterator_remove(&it);
6226         btstack_memory_whitelist_entry_free(entry);
6227     }
6228 }
6229 
6230 /**
6231  * @brief Clear Whitelist
6232  * @returns 0 if ok
6233  */
6234 uint8_t gap_whitelist_clear(void){
6235     hci_whitelist_clear();
6236     hci_run();
6237     return ERROR_CODE_SUCCESS;
6238 }
6239 
6240 /**
6241  * @brief Add Device to Whitelist
6242  * @param address_typ
6243  * @param address
6244  * @returns 0 if ok
6245  */
6246 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6247     uint8_t status = hci_whitelist_add(address_type, address);
6248     if (status){
6249         return status;
6250     }
6251     hci_run();
6252     return ERROR_CODE_SUCCESS;
6253 }
6254 
6255 /**
6256  * @brief Remove Device from Whitelist
6257  * @param address_typ
6258  * @param address
6259  * @returns 0 if ok
6260  */
6261 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6262     uint8_t status = hci_whitelist_remove(address_type, address);
6263     if (status){
6264         return status;
6265     }
6266     hci_run();
6267     return ERROR_CODE_SUCCESS;
6268 }
6269 
6270 #ifdef ENABLE_LE_CENTRAL
6271 /**
6272  *  @brief Connect with Whitelist
6273  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6274  *  @returns - if ok
6275  */
6276 uint8_t gap_connect_with_whitelist(void){
6277     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6278         return ERROR_CODE_COMMAND_DISALLOWED;
6279     }
6280     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6281     hci_run();
6282     return ERROR_CODE_SUCCESS;
6283 }
6284 
6285 /**
6286  * @brief Auto Connection Establishment - Start Connecting to device
6287  * @param address_typ
6288  * @param address
6289  * @returns 0 if ok
6290  */
6291 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6292     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6293         return ERROR_CODE_COMMAND_DISALLOWED;
6294     }
6295 
6296     uint8_t status = hci_whitelist_add(address_type, address);
6297     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6298         return status;
6299     }
6300 
6301     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6302 
6303     hci_run();
6304     return ERROR_CODE_SUCCESS;
6305 }
6306 
6307 /**
6308  * @brief Auto Connection Establishment - Stop Connecting to device
6309  * @param address_typ
6310  * @param address
6311  * @returns 0 if ok
6312  */
6313 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6314     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6315         return ERROR_CODE_COMMAND_DISALLOWED;
6316     }
6317 
6318     hci_whitelist_remove(address_type, address);
6319     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6320         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6321     }
6322     hci_run();
6323     return 0;
6324 }
6325 
6326 /**
6327  * @brief Auto Connection Establishment - Stop everything
6328  * @note  Convenience function to stop all active auto connection attempts
6329  */
6330 uint8_t gap_auto_connection_stop_all(void){
6331     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6332         return ERROR_CODE_COMMAND_DISALLOWED;
6333     }
6334     hci_whitelist_clear();
6335     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6336     hci_run();
6337     return ERROR_CODE_SUCCESS;
6338 }
6339 
6340 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6341     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6342     if (!conn) return 0;
6343     return conn->le_connection_interval;
6344 }
6345 #endif
6346 #endif
6347 
6348 #ifdef ENABLE_CLASSIC
6349 /**
6350  * @brief Set Extended Inquiry Response data
6351  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6352  * @note has to be done before stack starts up
6353  */
6354 void gap_set_extended_inquiry_response(const uint8_t * data){
6355     hci_stack->eir_data = data;
6356     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6357     hci_run();
6358 }
6359 
6360 /**
6361  * @brief Start GAP Classic Inquiry
6362  * @param duration in 1.28s units
6363  * @return 0 if ok
6364  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6365  */
6366 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6367     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6368     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6369     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6370         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6371     }
6372     hci_stack->inquiry_state = duration_in_1280ms_units;
6373     hci_run();
6374     return 0;
6375 }
6376 
6377 /**
6378  * @brief Stop GAP Classic Inquiry
6379  * @returns 0 if ok
6380  */
6381 int gap_inquiry_stop(void){
6382     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6383         // emit inquiry complete event, before it even started
6384         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6385         hci_emit_event(event, sizeof(event), 1);
6386         return 0;
6387     }
6388     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6389     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6390     hci_run();
6391     return 0;
6392 }
6393 
6394 void gap_inquiry_set_lap(uint32_t lap){
6395     hci_stack->inquiry_lap = lap;
6396 }
6397 
6398 
6399 /**
6400  * @brief Remote Name Request
6401  * @param addr
6402  * @param page_scan_repetition_mode
6403  * @param clock_offset only used when bit 15 is set
6404  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6405  */
6406 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6407     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6408     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6409     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6410     hci_stack->remote_name_clock_offset = clock_offset;
6411     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6412     hci_run();
6413     return 0;
6414 }
6415 
6416 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6417     hci_stack->gap_pairing_state = state;
6418     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6419     hci_run();
6420     return 0;
6421 }
6422 
6423 /**
6424  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6425  * @param addr
6426  * @param pin_data
6427  * @param pin_len
6428  * @return 0 if ok
6429  */
6430 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6431     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6432     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6433     hci_stack->gap_pairing_pin_len = pin_len;
6434     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6435 }
6436 
6437 /**
6438  * @brief Legacy Pairing Pin Code Response
6439  * @param addr
6440  * @param pin
6441  * @return 0 if ok
6442  */
6443 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6444     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6445 }
6446 
6447 /**
6448  * @brief Abort Legacy Pairing
6449  * @param addr
6450  * @param pin
6451  * @return 0 if ok
6452  */
6453 int gap_pin_code_negative(bd_addr_t addr){
6454     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6455     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6456 }
6457 
6458 /**
6459  * @brief SSP Passkey Response
6460  * @param addr
6461  * @param passkey
6462  * @return 0 if ok
6463  */
6464 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6465     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6466     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6467     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6468 }
6469 
6470 /**
6471  * @brief Abort SSP Passkey Entry/Pairing
6472  * @param addr
6473  * @param pin
6474  * @return 0 if ok
6475  */
6476 int gap_ssp_passkey_negative(const bd_addr_t addr){
6477     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6478     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6479 }
6480 
6481 /**
6482  * @brief Accept SSP Numeric Comparison
6483  * @param addr
6484  * @param passkey
6485  * @return 0 if ok
6486  */
6487 int gap_ssp_confirmation_response(const bd_addr_t addr){
6488     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6489     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6490 }
6491 
6492 /**
6493  * @brief Abort SSP Numeric Comparison/Pairing
6494  * @param addr
6495  * @param pin
6496  * @return 0 if ok
6497  */
6498 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6499     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6500     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6501 }
6502 
6503 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6504 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6505     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6506     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6507     connectionSetAuthenticationFlags(conn, flag);
6508     hci_run();
6509     return ERROR_CODE_SUCCESS;
6510 }
6511 #endif
6512 
6513 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6514 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6515     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6516 }
6517 
6518 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6519     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6520 }
6521 #endif
6522 
6523 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6524 /**
6525  * @brief Report Remote OOB Data
6526  * @param bd_addr
6527  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6528  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6529  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6530  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6531  */
6532 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){
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     connection->classic_oob_c_192 = c_192;
6538     connection->classic_oob_r_192 = r_192;
6539 
6540     // ignore P-256 if not supported by us
6541     if (hci_stack->secure_connections_active){
6542         connection->classic_oob_c_256 = c_256;
6543         connection->classic_oob_r_256 = r_256;
6544     }
6545 
6546     return ERROR_CODE_SUCCESS;
6547 }
6548 /**
6549  * @brief Generate new OOB data
6550  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6551  */
6552 void gap_ssp_generate_oob_data(void){
6553     hci_stack->classic_read_local_oob_data = true;
6554     hci_run();
6555 }
6556 
6557 #endif
6558 
6559 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6560 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6561     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6562     if (connection == NULL) {
6563         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6564     }
6565 
6566     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6567     connection->link_key_type = type;
6568 
6569     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6570 }
6571 
6572 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6573 /**
6574  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6575  * @param inquiry_mode see bluetooth_defines.h
6576  */
6577 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6578     hci_stack->inquiry_mode = inquiry_mode;
6579 }
6580 
6581 /**
6582  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6583  */
6584 void hci_set_sco_voice_setting(uint16_t voice_setting){
6585     hci_stack->sco_voice_setting = voice_setting;
6586 }
6587 
6588 /**
6589  * @brief Get SCO Voice Setting
6590  * @return current voice setting
6591  */
6592 uint16_t hci_get_sco_voice_setting(void){
6593     return hci_stack->sco_voice_setting;
6594 }
6595 
6596 static int hci_have_usb_transport(void){
6597     if (!hci_stack->hci_transport) return 0;
6598     const char * transport_name = hci_stack->hci_transport->name;
6599     if (!transport_name) return 0;
6600     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6601 }
6602 
6603 /** @brief Get SCO packet length for current SCO Voice setting
6604  *  @note  Using SCO packets of the exact length is required for USB transfer
6605  *  @return Length of SCO packets in bytes (not audio frames)
6606  */
6607 uint16_t hci_get_sco_packet_length(void){
6608     uint16_t sco_packet_length = 0;
6609 
6610 #ifdef ENABLE_SCO_OVER_HCI
6611     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6612     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6613 
6614     if (hci_have_usb_transport()){
6615         // see Core Spec for H2 USB Transfer.
6616         // 3 byte SCO header + 24 bytes per connection
6617         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6618         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6619     } else {
6620         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6621         sco_packet_length = 3 + 60 * multiplier;
6622         // assert that it still fits inside an SCO buffer
6623         if (sco_packet_length > hci_stack->sco_data_packet_length){
6624             sco_packet_length = 3 + 60;
6625         }
6626     }
6627 #endif
6628 
6629 #ifdef HAVE_SCO_TRANSPORT
6630     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6631     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6632     sco_packet_length = 3 + 60 * multiplier;
6633 #endif
6634     return sco_packet_length;
6635 }
6636 
6637 /**
6638 * @brief Sets the master/slave policy
6639 * @param policy (0: attempt to become master, 1: let connecting device decide)
6640 */
6641 void hci_set_master_slave_policy(uint8_t policy){
6642     hci_stack->master_slave_policy = policy;
6643 }
6644 
6645 #endif
6646 
6647 HCI_STATE hci_get_state(void){
6648     return hci_stack->state;
6649 }
6650 
6651 #ifdef ENABLE_CLASSIC
6652 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6653     hci_stack->gap_classic_accept_callback = accept_callback;
6654 }
6655 #endif
6656 
6657 /**
6658  * @brief Set callback for Bluetooth Hardware Error
6659  */
6660 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6661     hci_stack->hardware_error_callback = fn;
6662 }
6663 
6664 void hci_disconnect_all(void){
6665     btstack_linked_list_iterator_t it;
6666     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6667     while (btstack_linked_list_iterator_has_next(&it)){
6668         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6669         if (con->state == SENT_DISCONNECT) continue;
6670         con->state = SEND_DISCONNECT;
6671     }
6672     hci_run();
6673 }
6674 
6675 uint16_t hci_get_manufacturer(void){
6676     return hci_stack->manufacturer;
6677 }
6678 
6679 #ifdef ENABLE_BLE
6680 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6681     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6682     if (!hci_con) return NULL;
6683     return &hci_con->sm_connection;
6684 }
6685 
6686 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6687 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6688 #endif
6689 
6690 int gap_encryption_key_size(hci_con_handle_t con_handle){
6691     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6692     if (hci_connection == NULL) return 0;
6693     if (hci_is_le_connection(hci_connection)){
6694 #ifdef ENABLE_BLE
6695         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6696         if (sm_conn->sm_connection_encrypted) {
6697             return sm_conn->sm_actual_encryption_key_size;
6698         }
6699 #endif
6700     } else {
6701 #ifdef ENABLE_CLASSIC
6702         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6703             return hci_connection->encryption_key_size;
6704         }
6705 #endif
6706     }
6707     return 0;
6708 }
6709 
6710 int gap_authenticated(hci_con_handle_t con_handle){
6711     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6712     if (hci_connection == NULL) return 0;
6713 
6714     switch (hci_connection->address_type){
6715 #ifdef ENABLE_BLE
6716         case BD_ADDR_TYPE_LE_PUBLIC:
6717         case BD_ADDR_TYPE_LE_RANDOM:
6718             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6719             return hci_connection->sm_connection.sm_connection_authenticated;
6720 #endif
6721 #ifdef ENABLE_CLASSIC
6722         case BD_ADDR_TYPE_SCO:
6723         case BD_ADDR_TYPE_ACL:
6724             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6725 #endif
6726         default:
6727             return 0;
6728     }
6729 }
6730 
6731 int gap_secure_connection(hci_con_handle_t con_handle){
6732     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6733     if (hci_connection == NULL) return 0;
6734 
6735     switch (hci_connection->address_type){
6736 #ifdef ENABLE_BLE
6737         case BD_ADDR_TYPE_LE_PUBLIC:
6738         case BD_ADDR_TYPE_LE_RANDOM:
6739             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6740             return hci_connection->sm_connection.sm_connection_sc;
6741 #endif
6742 #ifdef ENABLE_CLASSIC
6743         case BD_ADDR_TYPE_SCO:
6744         case BD_ADDR_TYPE_ACL:
6745             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6746 #endif
6747         default:
6748             return 0;
6749     }
6750 }
6751 
6752 bool gap_bonded(hci_con_handle_t con_handle){
6753 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6754 	if (hci_connection == NULL) return 0;
6755 
6756 #ifdef ENABLE_CLASSIC
6757 	link_key_t link_key;
6758 	link_key_type_t link_key_type;
6759 #endif
6760 	switch (hci_connection->address_type){
6761 #ifdef ENABLE_BLE
6762 		case BD_ADDR_TYPE_LE_PUBLIC:
6763 		case BD_ADDR_TYPE_LE_RANDOM:
6764 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6765 #endif
6766 #ifdef ENABLE_CLASSIC
6767 		case BD_ADDR_TYPE_SCO:
6768 		case BD_ADDR_TYPE_ACL:
6769 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6770 #endif
6771 		default:
6772 			return false;
6773 	}
6774 }
6775 
6776 #ifdef ENABLE_BLE
6777 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6778     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6779     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6780     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6781     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6782     return sm_conn->sm_connection_authorization_state;
6783 }
6784 #endif
6785 
6786 #ifdef ENABLE_CLASSIC
6787 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){
6788     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6789     if (!conn) return GAP_CONNECTION_INVALID;
6790     conn->sniff_min_interval = sniff_min_interval;
6791     conn->sniff_max_interval = sniff_max_interval;
6792     conn->sniff_attempt = sniff_attempt;
6793     conn->sniff_timeout = sniff_timeout;
6794     hci_run();
6795     return 0;
6796 }
6797 
6798 /**
6799  * @brief Exit Sniff mode
6800  * @param con_handle
6801  @ @return 0 if ok
6802  */
6803 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6804     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6805     if (!conn) return GAP_CONNECTION_INVALID;
6806     conn->sniff_min_interval = 0xffff;
6807     hci_run();
6808     return 0;
6809 }
6810 
6811 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){
6812     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6813     if (!conn) return GAP_CONNECTION_INVALID;
6814     conn->sniff_subrating_max_latency = max_latency;
6815     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6816     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6817     hci_run();
6818     return ERROR_CODE_SUCCESS;
6819 }
6820 
6821 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){
6822     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6823     if (!conn) return GAP_CONNECTION_INVALID;
6824     conn->qos_service_type = service_type;
6825     conn->qos_token_rate = token_rate;
6826     conn->qos_peak_bandwidth = peak_bandwidth;
6827     conn->qos_latency = latency;
6828     conn->qos_delay_variation = delay_variation;
6829     hci_run();
6830     return ERROR_CODE_SUCCESS;
6831 }
6832 
6833 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6834     hci_stack->new_page_scan_interval = page_scan_interval;
6835     hci_stack->new_page_scan_window = page_scan_window;
6836     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6837     hci_run();
6838 }
6839 
6840 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6841     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6842     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6843     hci_run();
6844 }
6845 
6846 #endif
6847 
6848 void hci_halting_defer(void){
6849     if (hci_stack->state != HCI_STATE_HALTING) return;
6850     switch (hci_stack->substate){
6851         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6852         case HCI_HALTING_CLOSE:
6853             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6854             break;
6855         default:
6856             break;
6857     }
6858 }
6859 
6860 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6861 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6862     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6863     if (le_device_db_index >= le_device_db_max_count()) return;
6864     uint8_t offset = le_device_db_index >> 3;
6865     uint8_t mask = 1 << (le_device_db_index & 7);
6866     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6867     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6868     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6869         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6870     }
6871 }
6872 
6873 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6874 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6875 	if (le_device_db_index >= le_device_db_max_count()) return;
6876 	uint8_t offset = le_device_db_index >> 3;
6877 	uint8_t mask = 1 << (le_device_db_index & 7);
6878 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6879 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6880 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6881 	}
6882 }
6883 
6884 uint8_t gap_load_resolving_list_from_le_device_db(void){
6885 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6886 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6887 	}
6888 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6889 		// restart le resolving list update
6890 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6891 	}
6892 	return ERROR_CODE_SUCCESS;
6893 }
6894 #endif
6895 
6896 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6897 void hci_setup_test_connections_fuzz(void){
6898     hci_connection_t * conn;
6899 
6900     // default address: 66:55:44:33:00:01
6901     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6902 
6903     // setup Controller info
6904     hci_stack->num_cmd_packets = 255;
6905     hci_stack->acl_packets_total_num = 255;
6906 
6907     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6908     addr[5] = 0x01;
6909     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6910     conn->con_handle = addr[5];
6911     conn->role  = HCI_ROLE_SLAVE;
6912     conn->state = RECEIVED_CONNECTION_REQUEST;
6913     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6914 
6915     // setup incoming Classic SCO connection with con handle 0x0002
6916     addr[5] = 0x02;
6917     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6918     conn->con_handle = addr[5];
6919     conn->role  = HCI_ROLE_SLAVE;
6920     conn->state = RECEIVED_CONNECTION_REQUEST;
6921     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6922 
6923     // setup ready Classic ACL connection with con handle 0x0003
6924     addr[5] = 0x03;
6925     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6926     conn->con_handle = addr[5];
6927     conn->role  = HCI_ROLE_SLAVE;
6928     conn->state = OPEN;
6929     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6930 
6931     // setup ready Classic SCO connection with con handle 0x0004
6932     addr[5] = 0x04;
6933     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6934     conn->con_handle = addr[5];
6935     conn->role  = HCI_ROLE_SLAVE;
6936     conn->state = OPEN;
6937     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6938 
6939     // setup ready LE ACL connection with con handle 0x005 and public address
6940     addr[5] = 0x05;
6941     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6942     conn->con_handle = addr[5];
6943     conn->role  = HCI_ROLE_SLAVE;
6944     conn->state = OPEN;
6945     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6946     conn->sm_connection.sm_connection_encrypted = 1;
6947 }
6948 
6949 void hci_free_connections_fuzz(void){
6950     btstack_linked_list_iterator_t it;
6951     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6952     while (btstack_linked_list_iterator_has_next(&it)){
6953         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6954         btstack_linked_list_iterator_remove(&it);
6955         btstack_memory_hci_connection_free(con);
6956     }
6957 }
6958 void hci_simulate_working_fuzz(void){
6959     hci_init_done();
6960     hci_stack->num_cmd_packets = 255;
6961 }
6962 #endif
6963