xref: /btstack/src/hci.c (revision e7c662fa0f0f1e9f6df07cd98cb47d0c289cbe69)
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 
1430     bool need_baud_change = false;
1431 
1432 #ifndef HAVE_HOST_CONTROLLER_API
1433     need_baud_change = hci_stack->config
1434             && hci_stack->chipset
1435             && hci_stack->chipset->set_baudrate_command
1436             && hci_stack->hci_transport->set_baudrate
1437             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1438 #endif
1439 
1440     switch (hci_stack->substate){
1441         case HCI_INIT_SEND_RESET:
1442             hci_state_reset();
1443 
1444 #ifndef HAVE_HOST_CONTROLLER_API
1445             // prepare reset if command complete not received in 100ms
1446             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1447             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1448             btstack_run_loop_add_timer(&hci_stack->timeout);
1449 #endif
1450             // send command
1451             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1452             hci_send_cmd(&hci_reset);
1453             break;
1454         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1455             hci_send_cmd(&hci_read_local_version_information);
1456             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1457             break;
1458         case HCI_INIT_SEND_READ_LOCAL_NAME:
1459             hci_send_cmd(&hci_read_local_name);
1460             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1461             break;
1462 
1463 #ifndef HAVE_HOST_CONTROLLER_API
1464         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1465             hci_state_reset();
1466             // prepare reset if command complete not received in 100ms
1467             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1468             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1469             btstack_run_loop_add_timer(&hci_stack->timeout);
1470             // send command
1471             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1472             hci_send_cmd(&hci_reset);
1473             break;
1474         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1475             hci_state_reset();
1476             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1477             hci_send_cmd(&hci_reset);
1478             break;
1479         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1480             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1481             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1482             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1483             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1484             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1485             break;
1486         }
1487         case HCI_INIT_SET_BD_ADDR:
1488             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1489             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1490             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1491             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1492             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1493             break;
1494         case HCI_INIT_SEND_BAUD_CHANGE:
1495             if (need_baud_change) {
1496                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1497                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1498                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1499                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1500                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1501                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1502                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1503                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1504                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1505                     btstack_run_loop_add_timer(&hci_stack->timeout);
1506                }
1507                break;
1508             }
1509 
1510             /* fall through */
1511 
1512         case HCI_INIT_CUSTOM_INIT:
1513             // Custom initialization
1514             if (hci_stack->chipset && hci_stack->chipset->next_command){
1515                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1516                 bool send_cmd = false;
1517                 switch (hci_stack->chipset_result){
1518                     case BTSTACK_CHIPSET_VALID_COMMAND:
1519                         send_cmd = true;
1520                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1521                         break;
1522                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1523                         send_cmd = true;
1524                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1525                         log_info("CSR Warm Boot");
1526                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1527                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1528                         btstack_run_loop_add_timer(&hci_stack->timeout);
1529                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1530                             && hci_stack->config
1531                             && hci_stack->chipset
1532                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1533                             && hci_stack->hci_transport->set_baudrate
1534                             && hci_transport_uart_get_main_baud_rate()){
1535                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1536                         } else {
1537                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1538                         }
1539                         break;
1540                     default:
1541                         break;
1542                 }
1543 
1544                 if (send_cmd){
1545                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1546                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1547                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1548                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1549                     break;
1550                 }
1551                 log_info("Init script done");
1552 
1553                 // Init script download on Broadcom chipsets causes:
1554                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1555                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1556                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1557 
1558                     // - baud rate to reset, restore UART baud rate if needed
1559                     if (need_baud_change) {
1560                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1561                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1562                         hci_stack->hci_transport->set_baudrate(baud_rate);
1563                     }
1564 
1565                     uint16_t bcm_delay_ms = 300;
1566                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1567                     //   -> Work around: wait here.
1568                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1569                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1570                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1571                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1572                     btstack_run_loop_add_timer(&hci_stack->timeout);
1573                     break;
1574                 }
1575             }
1576             /* fall through */
1577 #endif
1578 
1579         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1580             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1581             hci_send_cmd(&hci_read_local_supported_commands);
1582             break;
1583         case HCI_INIT_READ_BD_ADDR:
1584             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1585             hci_send_cmd(&hci_read_bd_addr);
1586             break;
1587         case HCI_INIT_READ_BUFFER_SIZE:
1588             // only read buffer size if supported
1589             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1590                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1591                 hci_send_cmd(&hci_read_buffer_size);
1592                 break;
1593             }
1594             /* fall through */
1595 
1596         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1597             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1598             hci_send_cmd(&hci_read_local_supported_features);
1599             break;
1600 
1601 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1602         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1603             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1604             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1605             break;
1606         case HCI_INIT_HOST_BUFFER_SIZE:
1607             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1608             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1609                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1610             break;
1611 #endif
1612 
1613         case HCI_INIT_SET_EVENT_MASK:
1614             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1615             if (hci_le_supported()){
1616                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1617             } else {
1618                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1619                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1620             }
1621             break;
1622 
1623 #ifdef ENABLE_CLASSIC
1624         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1625             if (gap_ssp_supported()){
1626                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1627                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1628                 break;
1629             }
1630             /* fall through */
1631 
1632         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1633             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1634             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1635             break;
1636         case HCI_INIT_WRITE_INQUIRY_MODE:
1637             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1638             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1639             break;
1640         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1641             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1642 			hci_stack->secure_connections_active = true;
1643             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1644             break;
1645         // only sent if ENABLE_SCO_OVER_HCI is defined
1646         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1647             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1648             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1649             break;
1650         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1651             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1652             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1653             break;
1654         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1655         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1656             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1657 #ifdef ENABLE_SCO_OVER_HCI
1658             log_info("BCM: Route SCO data via HCI transport");
1659             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1660 #endif
1661 #ifdef ENABLE_SCO_OVER_PCM
1662             log_info("BCM: Route SCO data via PCM interface");
1663 #ifdef ENABLE_BCM_PCM_WBS
1664             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1665             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1666 #else
1667             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1668             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1669 #endif
1670 #endif
1671             break;
1672 #ifdef ENABLE_SCO_OVER_PCM
1673         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1674             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1675             log_info("BCM: Config PCM interface for I2S");
1676 #ifdef ENABLE_BCM_PCM_WBS
1677             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1678             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1679 #else
1680             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1681             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1682 #endif
1683             break;
1684 #endif
1685 #endif
1686 
1687 #ifdef ENABLE_BLE
1688         // LE INIT
1689         case HCI_INIT_LE_READ_BUFFER_SIZE:
1690             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1691             hci_send_cmd(&hci_le_read_buffer_size);
1692             break;
1693         case HCI_INIT_LE_SET_EVENT_MASK:
1694             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1695             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1696             break;
1697         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1698             // LE Supported Host = 1, Simultaneous Host = 0
1699             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1700             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1701             break;
1702 #endif
1703 
1704 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1705         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1706             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1707             hci_send_cmd(&hci_le_read_maximum_data_length);
1708             break;
1709         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1710             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1711             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1712             break;
1713 #endif
1714 
1715 #ifdef ENABLE_LE_CENTRAL
1716         case HCI_INIT_READ_WHITE_LIST_SIZE:
1717             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1718             hci_send_cmd(&hci_le_read_white_list_size);
1719             break;
1720         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1721             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1722             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);
1723             break;
1724 #endif
1725         default:
1726             return;
1727     }
1728 }
1729 
1730 static void hci_init_done(void){
1731 #ifdef ENABLE_CLASSIC
1732     // init sequence complete, check if GAP Tasks are completed
1733     if (hci_stack->gap_tasks != 0) {
1734         hci_run_gap_tasks_classic();
1735         return;
1736     }
1737 #endif
1738 
1739     // done. tell the app
1740     log_info("hci_init_done -> HCI_STATE_WORKING");
1741     hci_stack->state = HCI_STATE_WORKING;
1742     hci_emit_state();
1743     hci_run();
1744 }
1745 
1746 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1747     bool command_completed = false;
1748     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1749         uint16_t opcode = little_endian_read_16(packet,3);
1750         if (opcode == hci_stack->last_cmd_opcode){
1751             command_completed = true;
1752             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1753         } else {
1754             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1755         }
1756     }
1757 
1758     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1759         uint8_t  status = packet[2];
1760         uint16_t opcode = little_endian_read_16(packet,4);
1761         if (opcode == hci_stack->last_cmd_opcode){
1762             if (status){
1763                 command_completed = true;
1764                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1765             } else {
1766                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1767             }
1768         } else {
1769             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1770         }
1771     }
1772 #ifndef HAVE_HOST_CONTROLLER_API
1773     // Vendor == CSR
1774     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1775         // TODO: track actual command
1776         command_completed = true;
1777     }
1778 
1779     // Vendor == Toshiba
1780     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1781         // TODO: track actual command
1782         command_completed = true;
1783         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1784         hci_stack->num_cmd_packets = 1;
1785     }
1786 #endif
1787 
1788     return command_completed;
1789 }
1790 
1791 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1792 
1793     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1794 
1795     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1796 
1797 #ifndef HAVE_HOST_CONTROLLER_API
1798 
1799     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1800     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1801     //
1802     // HCI Reset
1803     // Timeout 100 ms
1804     // HCI Reset
1805     // Command Complete Reset
1806     // HCI Read Local Version Information
1807     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1808     // hang...
1809     //
1810     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1811     if (!command_completed
1812             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1813             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1814 
1815         uint16_t opcode = little_endian_read_16(packet,3);
1816         if (opcode == hci_reset.opcode){
1817             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1818             return;
1819         }
1820     }
1821 
1822     // CSR & H5
1823     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1824     if (!command_completed
1825             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1826             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1827 
1828         uint16_t opcode = little_endian_read_16(packet,3);
1829         if (opcode == hci_reset.opcode){
1830             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1831             return;
1832         }
1833     }
1834 
1835     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1836     // fix: Correct substate and behave as command below
1837     if (command_completed){
1838         switch (hci_stack->substate){
1839             case HCI_INIT_SEND_RESET:
1840                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1841                 break;
1842             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1843                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1844                 break;
1845             default:
1846                 break;
1847         }
1848     }
1849 
1850 #endif
1851 
1852     if (!command_completed) return;
1853 
1854     bool need_baud_change = false;
1855     bool need_addr_change = false;
1856 
1857 #ifndef HAVE_HOST_CONTROLLER_API
1858     need_baud_change = hci_stack->config
1859                         && hci_stack->chipset
1860                         && hci_stack->chipset->set_baudrate_command
1861                         && hci_stack->hci_transport->set_baudrate
1862                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1863 
1864     need_addr_change = hci_stack->custom_bd_addr_set
1865                         && hci_stack->chipset
1866                         && hci_stack->chipset->set_bd_addr_command;
1867 #endif
1868 
1869     switch(hci_stack->substate){
1870 
1871 #ifndef HAVE_HOST_CONTROLLER_API
1872         case HCI_INIT_SEND_RESET:
1873             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1874             // fix: just correct substate and behave as command below
1875 
1876             /* fall through */
1877 #endif
1878 
1879         case HCI_INIT_W4_SEND_RESET:
1880             btstack_run_loop_remove_timer(&hci_stack->timeout);
1881             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1882             return;
1883 
1884 #ifndef HAVE_HOST_CONTROLLER_API
1885         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1886             // for STLC2500D, baud rate change already happened.
1887             // for others, baud rate gets changed now
1888             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1889                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1890                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1891                 hci_stack->hci_transport->set_baudrate(baud_rate);
1892             }
1893             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1894             return;
1895         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1896             btstack_run_loop_remove_timer(&hci_stack->timeout);
1897             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1898             return;
1899         case HCI_INIT_W4_CUSTOM_INIT:
1900             // repeat custom init
1901             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1902             return;
1903 #endif
1904 
1905         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1906             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1907               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1908                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1909                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1910                 return;
1911             }
1912             if (need_addr_change){
1913                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1914                 return;
1915             }
1916             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1917             return;
1918 #ifndef HAVE_HOST_CONTROLLER_API
1919         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1920             if (need_baud_change){
1921                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1922                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1923                 hci_stack->hci_transport->set_baudrate(baud_rate);
1924             }
1925             if (need_addr_change){
1926                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1927                 return;
1928             }
1929             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1930             return;
1931         case HCI_INIT_W4_SET_BD_ADDR:
1932             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1933             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1934             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1935                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1936                 return;
1937             }
1938             // skipping st warm boot
1939             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1940             return;
1941         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1942             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1943             return;
1944 #endif
1945         case HCI_INIT_W4_SET_EVENT_MASK:
1946             // skip Classic init commands for LE only chipsets
1947             if (!hci_classic_supported()){
1948 #ifdef ENABLE_BLE
1949                 if (hci_le_supported()){
1950                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1951                     return;
1952                 }
1953 #endif
1954                 log_error("Neither BR/EDR nor LE supported");
1955                 hci_init_done();
1956                 return;
1957             }
1958             hci_stack->substate = HCI_INIT_WRITE_SIMPLE_PAIRING_MODE;
1959             return;
1960 
1961 #ifdef ENABLE_BLE
1962         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1963             // skip write le host if not supported (e.g. on LE only EM9301)
1964             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1965             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1966             return;
1967 
1968 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1969         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1970             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1971             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1972                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1973                 return;
1974             }
1975             // explicit fall through to reduce repetitions
1976 
1977 #ifdef ENABLE_LE_CENTRAL
1978             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1979 #else
1980             hci_init_done();
1981 #endif
1982             return;
1983 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1984 
1985 #endif  /* ENABLE_BLE */
1986 
1987         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1988             // skip write secure connections host support if not supported or disabled
1989             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1990                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1991                 return;
1992             }
1993             break;
1994 
1995 #ifdef ENABLE_SCO_OVER_HCI
1996         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1997             // skip write synchronous flow control if not supported
1998             if (hci_stack->local_supported_commands[0] & 0x04) break;
1999             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
2000 
2001             /* fall through */
2002 
2003         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2004             // skip write default erroneous data reporting if not supported
2005             if (hci_stack->local_supported_commands[0] & 0x08) break;
2006             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
2007 
2008             /* fall through */
2009 
2010         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
2011             // skip bcm set sco pcm config on non-Broadcom chipsets
2012             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
2013             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2014 
2015             /* fall through */
2016 
2017         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
2018             if (!hci_le_supported()){
2019                 // SKIP LE init for Classic only configuration
2020                 hci_init_done();
2021                 return;
2022             }
2023             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2024             break;
2025 
2026 #else /* !ENABLE_SCO_OVER_HCI */
2027 
2028         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2029 #ifdef ENABLE_SCO_OVER_PCM
2030             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
2031                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
2032                 return;
2033             }
2034 #endif
2035             /* fall through */
2036 
2037         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
2038 #ifdef ENABLE_BLE
2039             if (hci_le_supported()){
2040                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
2041                 return;
2042             }
2043 #endif
2044             // SKIP LE init for Classic only configuration
2045             hci_init_done();
2046             return;
2047 #endif /* ENABLE_SCO_OVER_HCI */
2048 
2049 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2050 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2051         // Response to command before init done state -> init done
2052         case (HCI_INIT_DONE-1):
2053             hci_init_done();
2054             return;
2055 #endif
2056 
2057         default:
2058             break;
2059     }
2060     hci_initializing_next_state();
2061 }
2062 
2063 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2064     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2065     bd_addr_t bd_address;
2066     (void)memcpy(&bd_address, conn->address, 6);
2067 
2068 #ifdef ENABLE_CLASSIC
2069     // cache needed data
2070     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2071 #endif
2072 
2073     // connection failed, remove entry
2074     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2075     btstack_memory_hci_connection_free( conn );
2076 
2077 #ifdef ENABLE_CLASSIC
2078     // notify client if dedicated bonding
2079     if (notify_dedicated_bonding_failed){
2080         log_info("hci notify_dedicated_bonding_failed");
2081         hci_emit_dedicated_bonding_result(bd_address, status);
2082     }
2083 
2084     // if authentication error, also delete link key
2085     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2086         gap_drop_link_key_for_bd_addr(bd_address);
2087     }
2088 #else
2089     UNUSED(status);
2090 #endif
2091 }
2092 
2093 #ifdef ENABLE_CLASSIC
2094 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2095     // SSP Controller
2096     if (features[6] & (1 << 3)){
2097         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2098     }
2099     // eSCO
2100     if (features[3] & (1<<7)){
2101         conn->remote_supported_features[0] |= 1;
2102     }
2103     // Extended features
2104     if (features[7] & (1<<7)){
2105         conn->remote_supported_features[0] |= 2;
2106     }
2107 }
2108 
2109 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2110     // SSP Host
2111     if (features[0] & (1 << 0)){
2112         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2113     }
2114     // SC Host
2115     if (features[0] & (1 << 3)){
2116         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2117     }
2118 }
2119 
2120 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2121     // SC Controller
2122     if (features[1] & (1 << 0)){
2123         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2124     }
2125 }
2126 
2127 static void hci_handle_remote_features_received(hci_connection_t * conn){
2128     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2129     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2130     if (conn->bonding_flags & BONDING_DEDICATED){
2131         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2132     }
2133 }
2134 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2135     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2136     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2137 }
2138 
2139 #endif
2140 
2141 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2142     // handle BT initialization
2143     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2144         hci_initializing_event_handler(packet, size);
2145     }
2146 
2147     // help with BT sleep
2148     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2149         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2150         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2151         hci_initializing_next_state();
2152     }
2153 }
2154 
2155 #ifdef ENABLE_CLASSIC
2156 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2157     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2158     conn->encryption_key_size = encryption_key_size;
2159 
2160     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2161         conn->requested_security_level = LEVEL_0;
2162         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2163         return;
2164     }
2165 
2166     // Request Authentication if not already done
2167     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2168     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2169 }
2170 #endif
2171 
2172 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2173     UNUSED(size);
2174 
2175     uint16_t manufacturer;
2176 #ifdef ENABLE_CLASSIC
2177     hci_con_handle_t handle;
2178     hci_connection_t * conn;
2179     uint8_t status;
2180 #endif
2181     // get num cmd packets - limit to 1 to reduce complexity
2182     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2183 
2184     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2185     switch (opcode){
2186         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2187             if (packet[5]) break;
2188             // terminate, name 248 chars
2189             packet[6+248] = 0;
2190             log_info("local name: %s", &packet[6]);
2191             break;
2192         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2193             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2194             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2195                 uint16_t acl_len = little_endian_read_16(packet, 6);
2196                 uint16_t sco_len = packet[8];
2197 
2198                 // determine usable ACL/SCO payload size
2199                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2200                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2201 
2202                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2203                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2204 
2205                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2206                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2207                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2208             }
2209             break;
2210         case HCI_OPCODE_HCI_READ_RSSI:
2211             if (packet[5] == ERROR_CODE_SUCCESS){
2212                 uint8_t event[5];
2213                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2214                 event[1] = 3;
2215                 (void)memcpy(&event[2], &packet[6], 3);
2216                 hci_emit_event(event, sizeof(event), 1);
2217             }
2218             break;
2219 #ifdef ENABLE_BLE
2220         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2221             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2222             hci_stack->le_acl_packets_total_num = packet[8];
2223             // determine usable ACL payload size
2224             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2225                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2226             }
2227             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2228             break;
2229 #endif
2230 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2231         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2232             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2233             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2234             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);
2235             break;
2236 #endif
2237 #ifdef ENABLE_LE_CENTRAL
2238         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2239             hci_stack->le_whitelist_capacity = packet[6];
2240             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2241             break;
2242 #endif
2243         case HCI_OPCODE_HCI_READ_BD_ADDR:
2244             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2245             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));
2246 #ifdef ENABLE_CLASSIC
2247             if (hci_stack->link_key_db){
2248                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2249             }
2250 #endif
2251             break;
2252 #ifdef ENABLE_CLASSIC
2253         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2254             hci_emit_discoverable_enabled(hci_stack->discoverable);
2255             break;
2256         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2257             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2258                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2259                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2260                 hci_emit_event(event, sizeof(event), 1);
2261             }
2262             break;
2263 #endif
2264         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2265             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2266 
2267 #ifdef ENABLE_CLASSIC
2268             // determine usable ACL packet types based on host buffer size and supported features
2269             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2270             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2271 #endif
2272             // Classic/LE
2273             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2274             break;
2275         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2276             manufacturer = little_endian_read_16(packet, 10);
2277             // map Cypress to Broadcom
2278             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2279                 log_info("Treat Cypress as Broadcom");
2280                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2281                 little_endian_store_16(packet, 10, manufacturer);
2282             }
2283             hci_stack->manufacturer = manufacturer;
2284             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2285             break;
2286         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2287             hci_stack->local_supported_commands[0] =
2288                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2289                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2290                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2291                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2292                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2293                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2294                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2295                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2296             hci_stack->local_supported_commands[1] =
2297                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2298                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2299                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2300                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2301                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2302             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2303             break;
2304 #ifdef ENABLE_CLASSIC
2305         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2306             if (packet[5]) return;
2307             hci_stack->synchronous_flow_control_enabled = 1;
2308             break;
2309         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2310             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2311             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2312             conn   = hci_connection_for_handle(handle);
2313             if (conn != NULL) {
2314                 uint8_t key_size = 0;
2315                 if (status == 0){
2316                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2317                     log_info("Handle %04x key Size: %u", handle, key_size);
2318                 } else {
2319                     key_size = 1;
2320                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2321                 }
2322                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2323             }
2324             break;
2325         // assert pairing complete event is emitted.
2326         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2327         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2328         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2329         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2330             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2331             // lookup connection by gap pairing addr
2332             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2333             if (conn == NULL) break;
2334             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2335             break;
2336 
2337 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2338         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2339         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2340             uint8_t event[67];
2341             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2342             event[1] = 65;
2343             (void)memset(&event[2], 0, 65);
2344             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2345                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2346                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2347                     event[2] = 3;
2348                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2349                 } else {
2350                     event[2] = 1;
2351                 }
2352             }
2353             hci_emit_event(event, sizeof(event), 0);
2354             break;
2355         }
2356 
2357         // note: only needed if user does not provide OOB data
2358         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2359             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2360             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2361             if (conn == NULL) break;
2362             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2363             break;
2364 #endif
2365 #endif
2366         default:
2367             break;
2368     }
2369 }
2370 
2371 #ifdef ENABLE_BLE
2372 static void event_handle_le_connection_complete(const uint8_t * packet){
2373 	bd_addr_t addr;
2374 	bd_addr_type_t addr_type;
2375 	hci_connection_t * conn;
2376 
2377 	// Connection management
2378 	reverse_bd_addr(&packet[8], addr);
2379 	addr_type = (bd_addr_type_t)packet[7];
2380 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2381 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2382 
2383 #ifdef ENABLE_LE_CENTRAL
2384 	// handle error: error is reported only to the initiator -> outgoing connection
2385 	if (packet[3]){
2386 
2387 		// handle cancelled outgoing connection
2388 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2389 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2390 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2391 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2392 		    // reset state
2393             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2394             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2395 			// get outgoing connection conn struct for direct connect
2396 			conn = gap_get_outgoing_connection();
2397 		}
2398 
2399 		// outgoing le connection establishment is done
2400 		if (conn){
2401 			// remove entry
2402 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2403 			btstack_memory_hci_connection_free( conn );
2404 		}
2405 		return;
2406 	}
2407 #endif
2408 
2409 	// on success, both hosts receive connection complete event
2410 	if (packet[6] == HCI_ROLE_MASTER){
2411 #ifdef ENABLE_LE_CENTRAL
2412 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2413 		// note: no hci_connection_t object exists yet for connect with whitelist
2414 		if (hci_is_le_connection_type(addr_type)){
2415 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2416 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2417 		}
2418 #endif
2419 	} else {
2420 #ifdef ENABLE_LE_PERIPHERAL
2421 		// if we're slave, it was an incoming connection, advertisements have stopped
2422 		hci_stack->le_advertisements_active = false;
2423 #endif
2424 	}
2425 
2426 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2427 	if (!conn){
2428 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2429 	}
2430 
2431 	// no memory, sorry.
2432 	if (!conn){
2433 		return;
2434 	}
2435 
2436 	conn->state = OPEN;
2437 	conn->role  = packet[6];
2438 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2439 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2440 
2441 #ifdef ENABLE_LE_PERIPHERAL
2442 	if (packet[6] == HCI_ROLE_SLAVE){
2443 		hci_update_advertisements_enabled_for_current_roles();
2444 	}
2445 #endif
2446 
2447     // init unenhanced att bearer mtu
2448     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2449     conn->att_connection.mtu_exchanged = false;
2450 
2451     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2452 
2453 	// restart timer
2454 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2455 	// btstack_run_loop_add_timer(&conn->timeout);
2456 
2457 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2458 
2459 	hci_emit_nr_connections_changed();
2460 }
2461 #endif
2462 
2463 #ifdef ENABLE_CLASSIC
2464 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){
2465     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2466     // LEVEL_4 is tested by l2cap
2467     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2468     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2469     if (level >= LEVEL_3){
2470         // MITM not possible without keyboard or display
2471         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2472         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2473 
2474         // MITM possible if one side has keyboard and the other has keyboard or display
2475         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2476         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2477 
2478         // MITM not possible if one side has only display and other side has no keyboard
2479         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2480         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2481     }
2482     // LEVEL 2 requires SSP, which is a given
2483     return true;
2484 }
2485 
2486 static bool btstack_is_null(uint8_t * data, uint16_t size){
2487     uint16_t i;
2488     for (i=0; i < size ; i++){
2489         if (data[i] != 0) {
2490             return false;
2491         }
2492     }
2493     return true;
2494 }
2495 
2496 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2497     // get requested security level
2498     gap_security_level_t requested_security_level = conn->requested_security_level;
2499     if (hci_stack->gap_secure_connections_only_mode){
2500         requested_security_level = LEVEL_4;
2501     }
2502 
2503     // assess security: LEVEL 4 requires SC
2504     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2505     if ((requested_security_level == LEVEL_4) &&
2506         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2507         !hci_remote_sc_enabled(conn)){
2508         log_info("Level 4 required, but SC not supported -> abort");
2509         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2510         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2511         return;
2512     }
2513 
2514     // assess security based on io capabilities
2515     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2516         // responder: fully validate io caps of both sides as well as OOB data
2517         bool security_possible = false;
2518         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2519 
2520 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2521         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2522         // so we merge the OOB data availability
2523         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2524         if (conn->classic_oob_c_192 != NULL){
2525             have_oob_data |= 1;
2526         }
2527         if (conn->classic_oob_c_256 != NULL){
2528             have_oob_data |= 2;
2529         }
2530         // for up to Level 3, either P-192 as well as P-256 will do
2531         // 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
2532         // if remote does not SC, we should not receive P-256 data either
2533         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2534             security_possible = true;
2535         }
2536         // for Level 4, P-256 is needed
2537         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2538             security_possible = true;
2539         }
2540 #endif
2541 
2542         if (security_possible == false){
2543             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2544             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2545             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2546             return;
2547         }
2548     } else {
2549         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2550 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2551 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2552         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2553             log_info("Level 3+ required, but no input/output -> abort");
2554             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2555             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2556             return;
2557         }
2558 #endif
2559 #endif
2560     }
2561 
2562 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2563     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2564         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2565     } else {
2566         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2567     }
2568 #endif
2569 }
2570 
2571 #endif
2572 
2573 static void event_handler(uint8_t *packet, uint16_t size){
2574 
2575     uint16_t event_length = packet[1];
2576 
2577     // assert packet is complete
2578     if (size != (event_length + 2u)){
2579         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2580         return;
2581     }
2582 
2583     bd_addr_type_t addr_type;
2584     hci_con_handle_t handle;
2585     hci_connection_t * conn;
2586     int i;
2587     int create_connection_cmd;
2588 
2589 #ifdef ENABLE_CLASSIC
2590     hci_link_type_t link_type;
2591     bd_addr_t addr;
2592 #endif
2593 
2594     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2595 
2596     switch (hci_event_packet_get_type(packet)) {
2597 
2598         case HCI_EVENT_COMMAND_COMPLETE:
2599             handle_command_complete_event(packet, size);
2600             break;
2601 
2602         case HCI_EVENT_COMMAND_STATUS:
2603             // get num cmd packets - limit to 1 to reduce complexity
2604             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2605 
2606             // check command status to detected failed outgoing connections
2607             create_connection_cmd = 0;
2608 #ifdef ENABLE_CLASSIC
2609             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2610                 create_connection_cmd = 1;
2611             }
2612 #endif
2613 #ifdef ENABLE_LE_CENTRAL
2614             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2615                 create_connection_cmd = 1;
2616             }
2617 #endif
2618             if (create_connection_cmd) {
2619                 uint8_t status = hci_event_command_status_get_status(packet);
2620                 addr_type = hci_stack->outgoing_addr_type;
2621                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2622                 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);
2623 
2624                 // reset outgoing address info
2625                 memset(hci_stack->outgoing_addr, 0, 6);
2626                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2627 
2628                 // on error
2629                 if (status != ERROR_CODE_SUCCESS){
2630 #ifdef ENABLE_LE_CENTRAL
2631                     if (hci_is_le_connection_type(addr_type)){
2632                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2633                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2634                     }
2635 #endif
2636                     // error => outgoing connection failed
2637                     if (conn != NULL){
2638                         hci_handle_connection_failed(conn, status);
2639                     }
2640                 }
2641             }
2642 
2643 #ifdef ENABLE_CLASSIC
2644             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2645                 uint8_t status = hci_event_command_status_get_status(packet);
2646                 log_info("command status (inquiry), status %x", status);
2647                 if (status == ERROR_CODE_SUCCESS) {
2648                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2649                 } else {
2650                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2651                 }
2652             }
2653 #endif
2654             break;
2655 
2656         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2657             if (size < 3) return;
2658             uint16_t num_handles = packet[2];
2659             if (size != (3u + num_handles * 4u)) return;
2660             uint16_t offset = 3;
2661             for (i=0; i<num_handles;i++){
2662                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2663                 offset += 2u;
2664                 uint16_t num_packets = little_endian_read_16(packet, offset);
2665                 offset += 2u;
2666 
2667                 conn = hci_connection_for_handle(handle);
2668                 if (!conn){
2669                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2670                     continue;
2671                 }
2672 
2673                 if (conn->num_packets_sent >= num_packets){
2674                     conn->num_packets_sent -= num_packets;
2675                 } else {
2676                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2677                     conn->num_packets_sent = 0;
2678                 }
2679                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2680 
2681 #ifdef ENABLE_CLASSIC
2682                 // For SCO, we do the can_send_now_check here
2683                 hci_notify_if_sco_can_send_now();
2684 #endif
2685             }
2686             break;
2687         }
2688 
2689 #ifdef ENABLE_CLASSIC
2690         case HCI_EVENT_INQUIRY_COMPLETE:
2691             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2692                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2693                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2694                 hci_emit_event(event, sizeof(event), 1);
2695             }
2696             break;
2697         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2698             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2699                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2700             }
2701             break;
2702         case HCI_EVENT_CONNECTION_REQUEST:
2703             reverse_bd_addr(&packet[2], addr);
2704             link_type = (hci_link_type_t) packet[11];
2705 
2706             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2707             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2708                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2709                 bd_addr_copy(hci_stack->decline_addr, addr);
2710                 break;
2711             }
2712 
2713             if (hci_stack->gap_classic_accept_callback != NULL){
2714                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2715                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2716                     bd_addr_copy(hci_stack->decline_addr, addr);
2717                     break;
2718                 }
2719             }
2720 
2721             // TODO: eval COD 8-10
2722             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2723             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2724             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2725             if (!conn) {
2726                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2727             }
2728             if (!conn) {
2729                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2730                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2731                 bd_addr_copy(hci_stack->decline_addr, addr);
2732                 break;
2733             }
2734             conn->role  = HCI_ROLE_SLAVE;
2735             conn->state = RECEIVED_CONNECTION_REQUEST;
2736             // store info about eSCO
2737             if (link_type == HCI_LINK_TYPE_ESCO){
2738                 conn->remote_supported_features[0] |= 1;
2739             }
2740             hci_run();
2741             break;
2742 
2743         case HCI_EVENT_CONNECTION_COMPLETE:
2744             // Connection management
2745             reverse_bd_addr(&packet[5], addr);
2746             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2747             addr_type = BD_ADDR_TYPE_ACL;
2748             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2749             if (conn) {
2750                 if (!packet[2]){
2751                     conn->state = OPEN;
2752                     conn->con_handle = little_endian_read_16(packet, 3);
2753 
2754                     // queue get remote feature
2755                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2756 
2757                     // queue set supervision timeout if we're master
2758                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2759                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2760                     }
2761 
2762                     // restart timer
2763                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2764                     btstack_run_loop_add_timer(&conn->timeout);
2765 
2766                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2767 
2768                     hci_emit_nr_connections_changed();
2769                 } else {
2770                     // connection failed
2771                     hci_handle_connection_failed(conn, packet[2]);
2772                 }
2773             }
2774             break;
2775 
2776         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2777             reverse_bd_addr(&packet[5], addr);
2778             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2779             if (packet[2]){
2780                 // connection failed
2781                 break;
2782             }
2783             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2784             if (!conn) {
2785                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2786             }
2787             if (!conn) {
2788                 break;
2789             }
2790             conn->state = OPEN;
2791             conn->con_handle = little_endian_read_16(packet, 3);
2792 
2793 #ifdef ENABLE_SCO_OVER_HCI
2794             // update SCO
2795             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2796                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2797             }
2798             // trigger can send now
2799             if (hci_have_usb_transport()){
2800                 hci_stack->sco_can_send_now = true;
2801             }
2802 #endif
2803 #ifdef HAVE_SCO_TRANSPORT
2804             // configure sco transport
2805             if (hci_stack->sco_transport != NULL){
2806                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2807                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2808             }
2809 #endif
2810             break;
2811 
2812         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2813             handle = little_endian_read_16(packet, 3);
2814             conn = hci_connection_for_handle(handle);
2815             if (!conn) break;
2816             if (!packet[2]){
2817                 const uint8_t * features = &packet[5];
2818                 hci_handle_remote_features_page_0(conn, features);
2819 
2820                 // read extended features if possible
2821                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2822                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2823                     break;
2824                 }
2825             }
2826             hci_handle_remote_features_received(conn);
2827             break;
2828 
2829         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2830             handle = little_endian_read_16(packet, 3);
2831             conn = hci_connection_for_handle(handle);
2832             if (!conn) break;
2833             // status = ok, page = 1
2834             if (!packet[2]) {
2835                 uint8_t page_number = packet[5];
2836                 uint8_t maximum_page_number = packet[6];
2837                 const uint8_t * features = &packet[7];
2838                 bool done = false;
2839                 switch (page_number){
2840                     case 1:
2841                         hci_handle_remote_features_page_1(conn, features);
2842                         if (maximum_page_number >= 2){
2843                             // get Secure Connections (Controller) from Page 2 if available
2844                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2845                         } else {
2846                             // otherwise, assume SC (Controller) == SC (Host)
2847                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2848                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2849                             }
2850                             done = true;
2851                         }
2852                         break;
2853                     case 2:
2854                         hci_handle_remote_features_page_2(conn, features);
2855                         done = true;
2856                         break;
2857                     default:
2858                         break;
2859                 }
2860                 if (!done) break;
2861             }
2862             hci_handle_remote_features_received(conn);
2863             break;
2864 
2865         case HCI_EVENT_LINK_KEY_REQUEST:
2866 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2867             hci_event_link_key_request_get_bd_addr(packet, addr);
2868             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2869             if (!conn) break;
2870 
2871             // lookup link key in db if not cached
2872             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2873                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2874             }
2875 
2876             // response sent by hci_run()
2877             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2878 #endif
2879             break;
2880 
2881         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2882             hci_event_link_key_request_get_bd_addr(packet, addr);
2883             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2884             if (!conn) break;
2885 
2886             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2887 
2888             // CVE-2020-26555: ignore NULL link key
2889             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2890             if (btstack_is_null(&packet[8], 16)) break;
2891 
2892             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2893             // Change Connection Encryption keeps link key type
2894             if (link_key_type != CHANGED_COMBINATION_KEY){
2895                 conn->link_key_type = link_key_type;
2896             }
2897 
2898             // cache link key. link keys stored in little-endian format for legacy reasons
2899             memcpy(&conn->link_key, &packet[8], 16);
2900 
2901             // only store link key:
2902             // - if bondable enabled
2903             if (hci_stack->bondable == false) break;
2904             // - if security level sufficient
2905             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2906             // - for SSP, also check if remote side requested bonding as well
2907             if (conn->link_key_type != COMBINATION_KEY){
2908                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2909                 if (!remote_bonding){
2910                     break;
2911                 }
2912             }
2913             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2914             break;
2915         }
2916 
2917         case HCI_EVENT_PIN_CODE_REQUEST:
2918             hci_event_pin_code_request_get_bd_addr(packet, addr);
2919             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2920             if (!conn) break;
2921 
2922             hci_pairing_started(conn, false);
2923             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2924             if (!hci_stack->bondable ){
2925                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2926                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2927                 hci_run();
2928                 return;
2929             }
2930             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2931             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2932                 log_info("Level 4 required, but SC not supported -> abort");
2933                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2934                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2935                 hci_run();
2936                 return;
2937             }
2938             break;
2939 
2940         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2941             hci_event_io_capability_response_get_bd_addr(packet, addr);
2942             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2943             if (!conn) break;
2944 
2945             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2946             hci_pairing_started(conn, true);
2947             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2948             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2949 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2950             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2951 #endif
2952             break;
2953 
2954         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2955             hci_event_io_capability_response_get_bd_addr(packet, addr);
2956             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2957             if (!conn) break;
2958 
2959             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2960             hci_connection_timestamp(conn);
2961             hci_pairing_started(conn, true);
2962             break;
2963 
2964 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2965         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2966             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2967             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2968             if (!conn) break;
2969 
2970             hci_connection_timestamp(conn);
2971 
2972             hci_pairing_started(conn, true);
2973 
2974             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2975             break;
2976 #endif
2977 
2978         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2979             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2980             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2981             if (!conn) break;
2982             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2983                 if (hci_stack->ssp_auto_accept){
2984                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2985                 };
2986             } else {
2987                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2988                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2989                 // don't forward event to app
2990                 hci_run();
2991                 return;
2992             }
2993             break;
2994 
2995         case HCI_EVENT_USER_PASSKEY_REQUEST:
2996             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2997             if (hci_stack->ssp_auto_accept){
2998                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2999             };
3000             break;
3001 
3002         case HCI_EVENT_MODE_CHANGE:
3003             handle = hci_event_mode_change_get_handle(packet);
3004             conn = hci_connection_for_handle(handle);
3005             if (!conn) break;
3006             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3007             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3008             break;
3009 #endif
3010 
3011         case HCI_EVENT_ENCRYPTION_CHANGE:
3012             handle = hci_event_encryption_change_get_connection_handle(packet);
3013             conn = hci_connection_for_handle(handle);
3014             if (!conn) break;
3015             if (hci_event_encryption_change_get_status(packet) == 0u) {
3016                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3017                 if (encryption_enabled){
3018                     if (hci_is_le_connection(conn)){
3019                         // For LE, we accept connection as encrypted
3020                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3021                     }
3022 #ifdef ENABLE_CLASSIC
3023                     else {
3024 
3025                         // dedicated bonding: send result and disconnect
3026                         if (conn->bonding_flags & BONDING_DEDICATED){
3027                             conn->bonding_flags &= ~BONDING_DEDICATED;
3028                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3029                             conn->bonding_status = packet[2];
3030                             break;
3031                         }
3032 
3033                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3034                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3035                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3036                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3037                             log_info("SC during pairing, but only E0 now -> abort");
3038                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3039                             break;
3040                         }
3041 
3042                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3043                         if (connected_uses_aes_ccm){
3044                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3045                         }
3046 
3047 #ifdef ENABLE_TESTING_SUPPORT
3048                         // work around for issue with PTS dongle
3049                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3050 #endif
3051 
3052                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3053                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3054                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3055                         } else {
3056                             // if not, pretend everything is perfect
3057                             hci_handle_read_encryption_key_size_complete(conn, 16);
3058                         }
3059                     }
3060 #endif
3061                 } else {
3062                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3063                 }
3064             }
3065 
3066             break;
3067 
3068 #ifdef ENABLE_CLASSIC
3069         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3070             handle = hci_event_authentication_complete_get_connection_handle(packet);
3071             conn = hci_connection_for_handle(handle);
3072             if (!conn) break;
3073 
3074             // clear authentication active flag
3075             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3076             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3077 
3078             // authenticated only if auth status == 0
3079             if (hci_event_authentication_complete_get_status(packet) == 0){
3080                 // authenticated
3081                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3082 
3083                 // If not already encrypted, start encryption
3084                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3085                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3086                     break;
3087                 }
3088             }
3089 
3090             // emit updated security level
3091             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3092             break;
3093 
3094         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3095             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3096             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3097             if (!conn) break;
3098 
3099             // treat successfully paired connection as authenticated
3100             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3101                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3102             }
3103 
3104             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3105             break;
3106 #endif
3107 
3108         // HCI_EVENT_DISCONNECTION_COMPLETE
3109         // has been split, to first notify stack before shutting connection down
3110         // see end of function, too.
3111         case HCI_EVENT_DISCONNECTION_COMPLETE:
3112             if (packet[2]) break;   // status != 0
3113             handle = little_endian_read_16(packet, 3);
3114             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3115             if (hci_stack->acl_fragmentation_total_size > 0u) {
3116                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3117                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3118                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3119                     hci_stack->acl_fragmentation_total_size = 0;
3120                     hci_stack->acl_fragmentation_pos = 0;
3121                     if (release_buffer){
3122                         hci_release_packet_buffer();
3123                     }
3124                 }
3125             }
3126 
3127             conn = hci_connection_for_handle(handle);
3128             if (!conn) break;
3129 #ifdef ENABLE_CLASSIC
3130             // pairing failed if it was ongoing
3131             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3132 #endif
3133 
3134             // emit dedicatd bonding event
3135             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3136                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3137             }
3138 
3139             // mark connection for shutdown, stop timers, reset state
3140             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3141             hci_connection_stop_timer(conn);
3142             hci_connection_init(conn);
3143 
3144 #ifdef ENABLE_BLE
3145 #ifdef ENABLE_LE_PERIPHERAL
3146             // re-enable advertisements for le connections if active
3147             if (hci_is_le_connection(conn)){
3148                 hci_update_advertisements_enabled_for_current_roles();
3149             }
3150 #endif
3151 #endif
3152             break;
3153 
3154         case HCI_EVENT_HARDWARE_ERROR:
3155             log_error("Hardware Error: 0x%02x", packet[2]);
3156             if (hci_stack->hardware_error_callback){
3157                 (*hci_stack->hardware_error_callback)(packet[2]);
3158             } else {
3159                 // if no special requests, just reboot stack
3160                 hci_power_control_off();
3161                 hci_power_control_on();
3162             }
3163             break;
3164 
3165 #ifdef ENABLE_CLASSIC
3166         case HCI_EVENT_ROLE_CHANGE:
3167             if (packet[2]) break;   // status != 0
3168             reverse_bd_addr(&packet[3], addr);
3169             addr_type = BD_ADDR_TYPE_ACL;
3170             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3171             if (!conn) break;
3172             conn->role = packet[9];
3173             break;
3174 #endif
3175 
3176         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3177             // release packet buffer only for asynchronous transport and if there are not further fragements
3178             if (hci_transport_synchronous()) {
3179                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3180                 return; // instead of break: to avoid re-entering hci_run()
3181             }
3182             hci_stack->acl_fragmentation_tx_active = 0;
3183             if (hci_stack->acl_fragmentation_total_size) break;
3184             hci_release_packet_buffer();
3185 
3186             // L2CAP receives this event via the hci_emit_event below
3187 
3188 #ifdef ENABLE_CLASSIC
3189             // For SCO, we do the can_send_now_check here
3190             hci_notify_if_sco_can_send_now();
3191 #endif
3192             break;
3193 
3194 #ifdef ENABLE_CLASSIC
3195         case HCI_EVENT_SCO_CAN_SEND_NOW:
3196             // For SCO, we do the can_send_now_check here
3197             hci_stack->sco_can_send_now = true;
3198             hci_notify_if_sco_can_send_now();
3199             return;
3200 
3201         // explode inquriy results for easier consumption
3202         case HCI_EVENT_INQUIRY_RESULT:
3203         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3204         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3205             gap_inquiry_explode(packet, size);
3206             break;
3207 #endif
3208 
3209 #ifdef ENABLE_BLE
3210         case HCI_EVENT_LE_META:
3211             switch (packet[2]){
3212 #ifdef ENABLE_LE_CENTRAL
3213                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3214                     // log_info("advertising report received");
3215                     if (!hci_stack->le_scanning_enabled) break;
3216                     le_handle_advertisement_report(packet, size);
3217                     break;
3218 #endif
3219                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3220 					event_handle_le_connection_complete(packet);
3221                     break;
3222 
3223                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3224                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3225                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3226                     conn = hci_connection_for_handle(handle);
3227                     if (!conn) break;
3228                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3229                     break;
3230 
3231                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3232                     // connection
3233                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3234                     conn = hci_connection_for_handle(handle);
3235                     if (conn) {
3236                         // read arguments
3237                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3238                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3239                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3240                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3241 
3242                         // validate against current connection parameter range
3243                         le_connection_parameter_range_t existing_range;
3244                         gap_get_connection_parameter_range(&existing_range);
3245                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3246                         if (update_parameter){
3247                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3248                             conn->le_conn_interval_min = le_conn_interval_min;
3249                             conn->le_conn_interval_max = le_conn_interval_max;
3250                             conn->le_conn_latency = le_conn_latency;
3251                             conn->le_supervision_timeout = le_supervision_timeout;
3252                         } else {
3253                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3254                         }
3255                     }
3256                     break;
3257 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3258                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3259                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3260                     conn = hci_connection_for_handle(handle);
3261                     if (conn) {
3262                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3263                     }
3264                     break;
3265 #endif
3266                 default:
3267                     break;
3268             }
3269             break;
3270 #endif
3271         case HCI_EVENT_VENDOR_SPECIFIC:
3272             // Vendor specific commands often create vendor specific event instead of num completed packets
3273             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3274             switch (hci_stack->manufacturer){
3275                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3276                     hci_stack->num_cmd_packets = 1;
3277                     break;
3278                 default:
3279                     break;
3280             }
3281             break;
3282         default:
3283             break;
3284     }
3285 
3286     handle_event_for_current_stack_state(packet, size);
3287 
3288     // notify upper stack
3289 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3290 
3291     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3292     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3293 		handle = little_endian_read_16(packet, 3);
3294 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3295 		// discard connection if app did not trigger a reconnect in the event handler
3296 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3297 			hci_shutdown_connection(aConn);
3298 		}
3299     }
3300 
3301 	// execute main loop
3302 	hci_run();
3303 }
3304 
3305 #ifdef ENABLE_CLASSIC
3306 
3307 #ifdef ENABLE_SCO_OVER_HCI
3308 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3309 static void sco_schedule_tx(hci_connection_t * conn);
3310 
3311 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3312     log_debug("SCO TX Timeout");
3313     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3314     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3315     if (!conn) return;
3316 
3317     // trigger send
3318     conn->sco_tx_ready = 1;
3319     // extra packet if CVSD but SCO buffer is too short
3320     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3321         conn->sco_tx_ready++;
3322     }
3323     hci_notify_if_sco_can_send_now();
3324 }
3325 
3326 
3327 #define SCO_TX_AFTER_RX_MS (6)
3328 
3329 static void sco_schedule_tx(hci_connection_t * conn){
3330 
3331     uint32_t now = btstack_run_loop_get_time_ms();
3332     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3333     int time_delta_ms = sco_tx_ms - now;
3334 
3335     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3336 
3337     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3338     btstack_run_loop_remove_timer(timer);
3339     btstack_run_loop_set_timer(timer, time_delta_ms);
3340     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3341     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3342     btstack_run_loop_add_timer(timer);
3343 }
3344 #endif
3345 
3346 static void sco_handler(uint8_t * packet, uint16_t size){
3347     // lookup connection struct
3348     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3349     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3350     if (!conn) return;
3351 
3352 #ifdef ENABLE_SCO_OVER_HCI
3353     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3354     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3355         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3356             packet[2] = 0x3c;
3357             memmove(&packet[3], &packet[23], 63);
3358             size = 63;
3359         }
3360     }
3361 
3362     if (hci_have_usb_transport()){
3363         // Nothing to do
3364     } else {
3365         // 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);
3366         if (hci_stack->synchronous_flow_control_enabled == 0){
3367             uint32_t now = btstack_run_loop_get_time_ms();
3368 
3369             if (!conn->sco_rx_valid){
3370                 // ignore first 10 packets
3371                 conn->sco_rx_count++;
3372                 // log_debug("sco rx count %u", conn->sco_rx_count);
3373                 if (conn->sco_rx_count == 10) {
3374                     // use first timestamp as is and pretent it just started
3375                     conn->sco_rx_ms = now;
3376                     conn->sco_rx_valid = 1;
3377                     conn->sco_rx_count = 0;
3378                     sco_schedule_tx(conn);
3379                 }
3380             } else {
3381                 // track expected arrival timme
3382                 conn->sco_rx_count++;
3383                 conn->sco_rx_ms += 7;
3384                 int delta = (int32_t) (now - conn->sco_rx_ms);
3385                 if (delta > 0){
3386                     conn->sco_rx_ms++;
3387                 }
3388                 // log_debug("sco rx %u", conn->sco_rx_ms);
3389                 sco_schedule_tx(conn);
3390             }
3391         }
3392     }
3393 #endif
3394 
3395     // deliver to app
3396     if (hci_stack->sco_packet_handler) {
3397         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3398     }
3399 
3400 #ifdef HAVE_SCO_TRANSPORT
3401     // We can send one packet for each received packet
3402     conn->sco_tx_ready++;
3403     hci_notify_if_sco_can_send_now();
3404 #endif
3405 
3406 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3407     conn->num_packets_completed++;
3408     hci_stack->host_completed_packets = 1;
3409     hci_run();
3410 #endif
3411 }
3412 #endif
3413 
3414 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3415     hci_dump_packet(packet_type, 1, packet, size);
3416     switch (packet_type) {
3417         case HCI_EVENT_PACKET:
3418             event_handler(packet, size);
3419             break;
3420         case HCI_ACL_DATA_PACKET:
3421             acl_handler(packet, size);
3422             break;
3423 #ifdef ENABLE_CLASSIC
3424         case HCI_SCO_DATA_PACKET:
3425             sco_handler(packet, size);
3426             break;
3427 #endif
3428         default:
3429             break;
3430     }
3431 }
3432 
3433 /**
3434  * @brief Add event packet handler.
3435  */
3436 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3437     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3438 }
3439 
3440 
3441 /** Register HCI packet handlers */
3442 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3443     hci_stack->acl_packet_handler = handler;
3444 }
3445 
3446 #ifdef ENABLE_CLASSIC
3447 /**
3448  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3449  */
3450 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3451     hci_stack->sco_packet_handler = handler;
3452 }
3453 #endif
3454 
3455 static void hci_state_reset(void){
3456     // no connections yet
3457     hci_stack->connections = NULL;
3458 
3459     // keep discoverable/connectable as this has been requested by the client(s)
3460     // hci_stack->discoverable = 0;
3461     // hci_stack->connectable = 0;
3462     // hci_stack->bondable = 1;
3463     // hci_stack->own_addr_type = 0;
3464 
3465     // buffer is free
3466     hci_stack->hci_packet_buffer_reserved = false;
3467 
3468     // no pending cmds
3469     hci_stack->decline_reason = 0;
3470 
3471     hci_stack->secure_connections_active = false;
3472 
3473 #ifdef ENABLE_CLASSIC
3474     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3475     hci_stack->gap_tasks =
3476             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3477             GAP_TASK_SET_CLASS_OF_DEVICE |
3478             GAP_TASK_SET_LOCAL_NAME |
3479             GAP_TASK_SET_EIR_DATA |
3480             GAP_TASK_WRITE_SCAN_ENABLE;
3481 #endif
3482 
3483 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3484     hci_stack->classic_read_local_oob_data = true;
3485     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3486 #endif
3487 
3488     // LE
3489 #ifdef ENABLE_BLE
3490     memset(hci_stack->le_random_address, 0, 6);
3491     hci_stack->le_random_address_set = 0;
3492 #endif
3493 #ifdef ENABLE_LE_CENTRAL
3494     hci_stack->le_scanning_active  = false;
3495     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3496     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3497     hci_stack->le_whitelist_capacity = 0;
3498 #endif
3499 #ifdef ENABLE_LE_PERIPHERAL
3500     hci_stack->le_advertisements_active = false;
3501     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3502         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3503     }
3504     if (hci_stack->le_advertisements_data != NULL){
3505         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3506     }
3507 #endif
3508 }
3509 
3510 #ifdef ENABLE_CLASSIC
3511 /**
3512  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3513  */
3514 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3515     // store and open remote device db
3516     hci_stack->link_key_db = link_key_db;
3517     if (hci_stack->link_key_db) {
3518         hci_stack->link_key_db->open();
3519     }
3520 }
3521 #endif
3522 
3523 void hci_init(const hci_transport_t *transport, const void *config){
3524 
3525 #ifdef HAVE_MALLOC
3526     if (!hci_stack) {
3527         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3528     }
3529 #else
3530     hci_stack = &hci_stack_static;
3531 #endif
3532     memset(hci_stack, 0, sizeof(hci_stack_t));
3533 
3534     // reference to use transport layer implementation
3535     hci_stack->hci_transport = transport;
3536 
3537     // reference to used config
3538     hci_stack->config = config;
3539 
3540     // setup pointer for outgoing packet buffer
3541     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3542 
3543     // max acl payload size defined in config.h
3544     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3545 
3546     // register packet handlers with transport
3547     transport->register_packet_handler(&packet_handler);
3548 
3549     hci_stack->state = HCI_STATE_OFF;
3550 
3551     // class of device
3552     hci_stack->class_of_device = 0x007a020c; // Smartphone
3553 
3554     // bondable by default
3555     hci_stack->bondable = 1;
3556 
3557 #ifdef ENABLE_CLASSIC
3558     // classic name
3559     hci_stack->local_name = default_classic_name;
3560 
3561     // Master slave policy
3562     hci_stack->master_slave_policy = 1;
3563 
3564     // Allow Role Switch
3565     hci_stack->allow_role_switch = 1;
3566 
3567     // Default / minimum security level = 2
3568     hci_stack->gap_security_level = LEVEL_2;
3569 
3570     // Default Security Mode 4
3571     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3572 
3573     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3574     hci_stack->gap_required_encyrption_key_size = 7;
3575 
3576     // Link Supervision Timeout
3577     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3578 
3579 #endif
3580 
3581     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3582     hci_stack->ssp_enable = 1;
3583     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3584     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3585     hci_stack->ssp_auto_accept = 1;
3586 
3587     // Secure Connections: enable (requires support from Controller)
3588     hci_stack->secure_connections_enable = true;
3589 
3590     // voice setting - signed 16 bit pcm data with CVSD over the air
3591     hci_stack->sco_voice_setting = 0x60;
3592 
3593 #ifdef ENABLE_LE_CENTRAL
3594     // connection parameter to use for outgoing connections
3595     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3596     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3597     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3598     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3599     hci_stack->le_connection_latency      = 4;         // 4
3600     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3601     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3602     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3603 
3604     // default LE Scanning
3605     hci_stack->le_scan_type     =   0x1; // active
3606     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3607     hci_stack->le_scan_window   =  0x30; //  30 ms
3608 #endif
3609 
3610 #ifdef ENABLE_LE_PERIPHERAL
3611     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3612 #endif
3613 
3614     // connection parameter range used to answer connection parameter update requests in l2cap
3615     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3616     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3617     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3618     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3619     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3620     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3621 
3622     hci_state_reset();
3623 }
3624 
3625 void hci_deinit(void){
3626 #ifdef HAVE_MALLOC
3627     if (hci_stack) {
3628         free(hci_stack);
3629     }
3630 #endif
3631     hci_stack = NULL;
3632 
3633 #ifdef ENABLE_CLASSIC
3634     disable_l2cap_timeouts = 0;
3635 #endif
3636 }
3637 
3638 /**
3639  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3640  */
3641 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3642     hci_stack->chipset = chipset_driver;
3643 
3644     // reset chipset driver - init is also called on power_up
3645     if (hci_stack->chipset && hci_stack->chipset->init){
3646         hci_stack->chipset->init(hci_stack->config);
3647     }
3648 }
3649 
3650 /**
3651  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3652  */
3653 void hci_set_control(const btstack_control_t *hardware_control){
3654     // references to used control implementation
3655     hci_stack->control = hardware_control;
3656     // init with transport config
3657     hardware_control->init(hci_stack->config);
3658 }
3659 
3660 void hci_close(void){
3661 
3662 #ifdef ENABLE_CLASSIC
3663     // close remote device db
3664     if (hci_stack->link_key_db) {
3665         hci_stack->link_key_db->close();
3666     }
3667 #endif
3668 
3669     btstack_linked_list_iterator_t lit;
3670     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3671     while (btstack_linked_list_iterator_has_next(&lit)){
3672         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3673         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3674         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3675         hci_shutdown_connection(connection);
3676     }
3677 
3678     hci_power_control(HCI_POWER_OFF);
3679 
3680 #ifdef HAVE_MALLOC
3681     free(hci_stack);
3682 #endif
3683     hci_stack = NULL;
3684 }
3685 
3686 #ifdef HAVE_SCO_TRANSPORT
3687 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3688     hci_stack->sco_transport = sco_transport;
3689     sco_transport->register_packet_handler(&packet_handler);
3690 }
3691 #endif
3692 
3693 #ifdef ENABLE_CLASSIC
3694 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3695     // validate ranage and set
3696     if (encryption_key_size < 7)  return;
3697     if (encryption_key_size > 16) return;
3698     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3699 }
3700 
3701 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3702     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3703         hci_stack->gap_security_mode = security_mode;
3704         return ERROR_CODE_SUCCESS;
3705     } else {
3706         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3707     }
3708 }
3709 
3710 gap_security_mode_t gap_get_security_mode(void){
3711     return hci_stack->gap_security_mode;
3712 }
3713 
3714 void gap_set_security_level(gap_security_level_t security_level){
3715     hci_stack->gap_security_level = security_level;
3716 }
3717 
3718 gap_security_level_t gap_get_security_level(void){
3719     if (hci_stack->gap_secure_connections_only_mode){
3720         return LEVEL_4;
3721     }
3722     return hci_stack->gap_security_level;
3723 }
3724 
3725 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3726     hci_stack->gap_minimal_service_security_level = security_level;
3727 }
3728 
3729 void gap_set_secure_connections_only_mode(bool enable){
3730     hci_stack->gap_secure_connections_only_mode = enable;
3731 }
3732 
3733 bool gap_get_secure_connections_only_mode(void){
3734     return hci_stack->gap_secure_connections_only_mode;
3735 }
3736 #endif
3737 
3738 #ifdef ENABLE_CLASSIC
3739 void gap_set_class_of_device(uint32_t class_of_device){
3740     hci_stack->class_of_device = class_of_device;
3741     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3742     hci_run();
3743 }
3744 
3745 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3746     hci_stack->default_link_policy_settings = default_link_policy_settings;
3747     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3748     hci_run();
3749 }
3750 
3751 void gap_set_allow_role_switch(bool allow_role_switch){
3752     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3753 }
3754 
3755 uint8_t hci_get_allow_role_switch(void){
3756     return  hci_stack->allow_role_switch;
3757 }
3758 
3759 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3760     hci_stack->link_supervision_timeout = link_supervision_timeout;
3761 }
3762 
3763 void hci_disable_l2cap_timeout_check(void){
3764     disable_l2cap_timeouts = 1;
3765 }
3766 #endif
3767 
3768 #ifndef HAVE_HOST_CONTROLLER_API
3769 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3770 void hci_set_bd_addr(bd_addr_t addr){
3771     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3772     hci_stack->custom_bd_addr_set = 1;
3773 }
3774 #endif
3775 
3776 // State-Module-Driver overview
3777 // state                    module  low-level
3778 // HCI_STATE_OFF             off      close
3779 // HCI_STATE_INITIALIZING,   on       open
3780 // HCI_STATE_WORKING,        on       open
3781 // HCI_STATE_HALTING,        on       open
3782 // HCI_STATE_SLEEPING,    off/sleep   close
3783 // HCI_STATE_FALLING_ASLEEP  on       open
3784 
3785 static int hci_power_control_on(void){
3786 
3787     // power on
3788     int err = 0;
3789     if (hci_stack->control && hci_stack->control->on){
3790         err = (*hci_stack->control->on)();
3791     }
3792     if (err){
3793         log_error( "POWER_ON failed");
3794         hci_emit_hci_open_failed();
3795         return err;
3796     }
3797 
3798     // int chipset driver
3799     if (hci_stack->chipset && hci_stack->chipset->init){
3800         hci_stack->chipset->init(hci_stack->config);
3801     }
3802 
3803     // init transport
3804     if (hci_stack->hci_transport->init){
3805         hci_stack->hci_transport->init(hci_stack->config);
3806     }
3807 
3808     // open transport
3809     err = hci_stack->hci_transport->open();
3810     if (err){
3811         log_error( "HCI_INIT failed, turning Bluetooth off again");
3812         if (hci_stack->control && hci_stack->control->off){
3813             (*hci_stack->control->off)();
3814         }
3815         hci_emit_hci_open_failed();
3816         return err;
3817     }
3818     return 0;
3819 }
3820 
3821 static void hci_power_control_off(void){
3822 
3823     log_info("hci_power_control_off");
3824 
3825     // close low-level device
3826     hci_stack->hci_transport->close();
3827 
3828     log_info("hci_power_control_off - hci_transport closed");
3829 
3830     // power off
3831     if (hci_stack->control && hci_stack->control->off){
3832         (*hci_stack->control->off)();
3833     }
3834 
3835     log_info("hci_power_control_off - control closed");
3836 
3837     hci_stack->state = HCI_STATE_OFF;
3838 }
3839 
3840 static void hci_power_control_sleep(void){
3841 
3842     log_info("hci_power_control_sleep");
3843 
3844 #if 0
3845     // don't close serial port during sleep
3846 
3847     // close low-level device
3848     hci_stack->hci_transport->close(hci_stack->config);
3849 #endif
3850 
3851     // sleep mode
3852     if (hci_stack->control && hci_stack->control->sleep){
3853         (*hci_stack->control->sleep)();
3854     }
3855 
3856     hci_stack->state = HCI_STATE_SLEEPING;
3857 }
3858 
3859 static int hci_power_control_wake(void){
3860 
3861     log_info("hci_power_control_wake");
3862 
3863     // wake on
3864     if (hci_stack->control && hci_stack->control->wake){
3865         (*hci_stack->control->wake)();
3866     }
3867 
3868 #if 0
3869     // open low-level device
3870     int err = hci_stack->hci_transport->open(hci_stack->config);
3871     if (err){
3872         log_error( "HCI_INIT failed, turning Bluetooth off again");
3873         if (hci_stack->control && hci_stack->control->off){
3874             (*hci_stack->control->off)();
3875         }
3876         hci_emit_hci_open_failed();
3877         return err;
3878     }
3879 #endif
3880 
3881     return 0;
3882 }
3883 
3884 static void hci_power_transition_to_initializing(void){
3885     // set up state machine
3886     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3887     hci_stack->hci_packet_buffer_reserved = false;
3888     hci_stack->state = HCI_STATE_INITIALIZING;
3889     hci_stack->substate = HCI_INIT_SEND_RESET;
3890 }
3891 
3892 // returns error
3893 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3894     int err;
3895     switch (power_mode){
3896         case HCI_POWER_ON:
3897             err = hci_power_control_on();
3898             if (err != 0) {
3899                 log_error("hci_power_control_on() error %d", err);
3900                 return err;
3901             }
3902             hci_power_transition_to_initializing();
3903             break;
3904         case HCI_POWER_OFF:
3905             // do nothing
3906             break;
3907         case HCI_POWER_SLEEP:
3908             // do nothing (with SLEEP == OFF)
3909             break;
3910         default:
3911             btstack_assert(false);
3912             break;
3913     }
3914     return ERROR_CODE_SUCCESS;
3915 }
3916 
3917 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3918     switch (power_mode){
3919         case HCI_POWER_ON:
3920             // do nothing
3921             break;
3922         case HCI_POWER_OFF:
3923             // no connections yet, just turn it off
3924             hci_power_control_off();
3925             break;
3926         case HCI_POWER_SLEEP:
3927             // no connections yet, just turn it off
3928             hci_power_control_sleep();
3929             break;
3930         default:
3931             btstack_assert(false);
3932             break;
3933     }
3934     return ERROR_CODE_SUCCESS;
3935 }
3936 
3937 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3938     switch (power_mode){
3939         case HCI_POWER_ON:
3940             // do nothing
3941             break;
3942         case HCI_POWER_OFF:
3943             // see hci_run
3944             hci_stack->state = HCI_STATE_HALTING;
3945             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3946             break;
3947         case HCI_POWER_SLEEP:
3948             // see hci_run
3949             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3950             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3951             break;
3952         default:
3953             btstack_assert(false);
3954             break;
3955     }
3956     return ERROR_CODE_SUCCESS;
3957 }
3958 
3959 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3960     switch (power_mode){
3961         case HCI_POWER_ON:
3962             hci_power_transition_to_initializing();
3963             break;
3964         case HCI_POWER_OFF:
3965             // do nothing
3966             break;
3967         case HCI_POWER_SLEEP:
3968             // see hci_run
3969             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3970             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3971             break;
3972         default:
3973             btstack_assert(false);
3974             break;
3975     }
3976     return ERROR_CODE_SUCCESS;
3977 }
3978 
3979 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3980     switch (power_mode){
3981         case HCI_POWER_ON:
3982             hci_power_transition_to_initializing();
3983             break;
3984         case HCI_POWER_OFF:
3985             // see hci_run
3986             hci_stack->state = HCI_STATE_HALTING;
3987             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3988             break;
3989         case HCI_POWER_SLEEP:
3990             // do nothing
3991             break;
3992         default:
3993             btstack_assert(false);
3994             break;
3995     }
3996     return ERROR_CODE_SUCCESS;
3997 }
3998 
3999 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4000     int err;
4001     switch (power_mode){
4002         case HCI_POWER_ON:
4003             err = hci_power_control_wake();
4004             if (err) return err;
4005             hci_power_transition_to_initializing();
4006             break;
4007         case HCI_POWER_OFF:
4008             hci_stack->state = HCI_STATE_HALTING;
4009             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4010             break;
4011         case HCI_POWER_SLEEP:
4012             // do nothing
4013             break;
4014         default:
4015             btstack_assert(false);
4016             break;
4017     }
4018     return ERROR_CODE_SUCCESS;
4019 }
4020 
4021 int hci_power_control(HCI_POWER_MODE power_mode){
4022     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4023     int err = 0;
4024     switch (hci_stack->state){
4025         case HCI_STATE_OFF:
4026             err = hci_power_control_state_off(power_mode);
4027             break;
4028         case HCI_STATE_INITIALIZING:
4029             err = hci_power_control_state_initializing(power_mode);
4030             break;
4031         case HCI_STATE_WORKING:
4032             err = hci_power_control_state_working(power_mode);
4033             break;
4034         case HCI_STATE_HALTING:
4035             err = hci_power_control_state_halting(power_mode);
4036             break;
4037         case HCI_STATE_FALLING_ASLEEP:
4038             err = hci_power_control_state_falling_asleep(power_mode);
4039             break;
4040         case HCI_STATE_SLEEPING:
4041             err = hci_power_control_state_sleeping(power_mode);
4042             break;
4043         default:
4044             btstack_assert(false);
4045             break;
4046     }
4047     if (err != 0){
4048         return err;
4049     }
4050 
4051     // create internal event
4052 	hci_emit_state();
4053 
4054 	// trigger next/first action
4055 	hci_run();
4056 
4057     return 0;
4058 }
4059 
4060 
4061 #ifdef ENABLE_CLASSIC
4062 
4063 static void hci_update_scan_enable(void){
4064     // 2 = page scan, 1 = inq scan
4065     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4066     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4067     hci_run();
4068 }
4069 
4070 void gap_discoverable_control(uint8_t enable){
4071     if (enable) enable = 1; // normalize argument
4072 
4073     if (hci_stack->discoverable == enable){
4074         hci_emit_discoverable_enabled(hci_stack->discoverable);
4075         return;
4076     }
4077 
4078     hci_stack->discoverable = enable;
4079     hci_update_scan_enable();
4080 }
4081 
4082 void gap_connectable_control(uint8_t enable){
4083     if (enable) enable = 1; // normalize argument
4084 
4085     // don't emit event
4086     if (hci_stack->connectable == enable) return;
4087 
4088     hci_stack->connectable = enable;
4089     hci_update_scan_enable();
4090 }
4091 #endif
4092 
4093 void gap_local_bd_addr(bd_addr_t address_buffer){
4094     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4095 }
4096 
4097 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4098 static void hci_host_num_completed_packets(void){
4099 
4100     // create packet manually as arrays are not supported and num_commands should not get reduced
4101     hci_reserve_packet_buffer();
4102     uint8_t * packet = hci_get_outgoing_packet_buffer();
4103 
4104     uint16_t size = 0;
4105     uint16_t num_handles = 0;
4106     packet[size++] = 0x35;
4107     packet[size++] = 0x0c;
4108     size++;  // skip param len
4109     size++;  // skip num handles
4110 
4111     // add { handle, packets } entries
4112     btstack_linked_item_t * it;
4113     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4114         hci_connection_t * connection = (hci_connection_t *) it;
4115         if (connection->num_packets_completed){
4116             little_endian_store_16(packet, size, connection->con_handle);
4117             size += 2;
4118             little_endian_store_16(packet, size, connection->num_packets_completed);
4119             size += 2;
4120             //
4121             num_handles++;
4122             connection->num_packets_completed = 0;
4123         }
4124     }
4125 
4126     packet[2] = size - 3;
4127     packet[3] = num_handles;
4128 
4129     hci_stack->host_completed_packets = 0;
4130 
4131     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4132     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4133 
4134     // release packet buffer for synchronous transport implementations
4135     if (hci_transport_synchronous()){
4136         hci_release_packet_buffer();
4137         hci_emit_transport_packet_sent();
4138     }
4139 }
4140 #endif
4141 
4142 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4143     UNUSED(ds);
4144     hci_stack->substate = HCI_HALTING_CLOSE;
4145     // allow packet handlers to defer final shutdown
4146     hci_emit_state();
4147     hci_run();
4148 }
4149 
4150 static bool hci_run_acl_fragments(void){
4151     if (hci_stack->acl_fragmentation_total_size > 0u) {
4152         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4153         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4154         if (connection) {
4155             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4156                 hci_send_acl_packet_fragments(connection);
4157                 return true;
4158             }
4159         } else {
4160             // connection gone -> discard further fragments
4161             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4162             hci_stack->acl_fragmentation_total_size = 0;
4163             hci_stack->acl_fragmentation_pos = 0;
4164         }
4165     }
4166     return false;
4167 }
4168 
4169 #ifdef ENABLE_CLASSIC
4170 static bool hci_run_general_gap_classic(void){
4171 
4172     // assert stack is working and classic is active
4173     if (hci_classic_supported() == false)      return false;
4174     if (hci_stack->state != HCI_STATE_WORKING) return false;
4175 
4176     // decline incoming connections
4177     if (hci_stack->decline_reason){
4178         uint8_t reason = hci_stack->decline_reason;
4179         hci_stack->decline_reason = 0;
4180         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4181         return true;
4182     }
4183 
4184     if (hci_stack->gap_tasks != 0){
4185         hci_run_gap_tasks_classic();
4186         return true;
4187     }
4188 
4189     // start/stop inquiry
4190     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4191         uint8_t duration = hci_stack->inquiry_state;
4192         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4193         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4194         return true;
4195     }
4196     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4197         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4198         hci_send_cmd(&hci_inquiry_cancel);
4199         return true;
4200     }
4201     // remote name request
4202     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4203         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4204         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4205                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4206         return true;
4207     }
4208 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4209     // Local OOB data
4210     if (hci_stack->classic_read_local_oob_data){
4211         hci_stack->classic_read_local_oob_data = false;
4212         if (hci_stack->local_supported_commands[1] & 0x10u){
4213             hci_send_cmd(&hci_read_local_extended_oob_data);
4214         } else {
4215             hci_send_cmd(&hci_read_local_oob_data);
4216         }
4217     }
4218 #endif
4219     // pairing
4220     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4221         uint8_t state = hci_stack->gap_pairing_state;
4222         uint8_t pin_code[16];
4223         switch (state){
4224             case GAP_PAIRING_STATE_SEND_PIN:
4225                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4226                 memset(pin_code, 0, 16);
4227                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4228                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4229                 break;
4230             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4231                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4232                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4233                 break;
4234             case GAP_PAIRING_STATE_SEND_PASSKEY:
4235                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4236                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4237                 break;
4238             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4239                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4240                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4241                 break;
4242             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4243                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4244                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4245                 break;
4246             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4247                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4248                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4249                 break;
4250             default:
4251                 break;
4252         }
4253         return true;
4254     }
4255     return false;
4256 }
4257 #endif
4258 
4259 #ifdef ENABLE_BLE
4260 static bool hci_run_general_gap_le(void){
4261 
4262     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4263 
4264     if (hci_stack->state != HCI_STATE_WORKING) return false;
4265     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4266 
4267 
4268     // Phase 1: collect what to stop
4269 
4270     bool scanning_stop = false;
4271     bool connecting_stop = false;
4272     bool advertising_stop = false;
4273 
4274 #ifndef ENABLE_LE_CENTRAL
4275     UNUSED(scanning_stop);
4276     UNUSED(connecting_stop);
4277 #endif
4278 #ifndef ENABLE_LE_PERIPHERAL
4279     UNUSED(advertising_stop);
4280 #endif
4281 
4282     // check if whitelist needs modification
4283     bool whitelist_modification_pending = false;
4284     btstack_linked_list_iterator_t lit;
4285     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4286     while (btstack_linked_list_iterator_has_next(&lit)){
4287         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4288         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4289             whitelist_modification_pending = true;
4290             break;
4291         }
4292     }
4293     // check if resolving list needs modification
4294     bool resolving_list_modification_pending = false;
4295 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4296     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4297 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4298         resolving_list_modification_pending = true;
4299     }
4300 #endif
4301 
4302 #ifdef ENABLE_LE_CENTRAL
4303     // scanning control
4304     if (hci_stack->le_scanning_active) {
4305         // stop if:
4306         // - parameter change required
4307         // - it's disabled
4308         // - whitelist change required but used for scanning
4309         // - resolving list modified
4310         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4311         if ((hci_stack->le_scanning_param_update) ||
4312             !hci_stack->le_scanning_enabled ||
4313             scanning_uses_whitelist ||
4314             resolving_list_modification_pending){
4315 
4316             scanning_stop = true;
4317         }
4318     }
4319 #endif
4320 
4321 #ifdef ENABLE_LE_CENTRAL
4322     // connecting control
4323     bool connecting_with_whitelist;
4324     switch (hci_stack->le_connecting_state){
4325         case LE_CONNECTING_DIRECT:
4326         case LE_CONNECTING_WHITELIST:
4327             // stop connecting if:
4328             // - connecting uses white and whitelist modification pending
4329             // - if it got disabled
4330             // - resolving list modified
4331             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4332             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4333                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4334                 resolving_list_modification_pending) {
4335 
4336                 connecting_stop = true;
4337             }
4338             break;
4339         default:
4340             break;
4341     }
4342 #endif
4343 
4344 #ifdef ENABLE_LE_PERIPHERAL
4345     // le advertisement control
4346     if (hci_stack->le_advertisements_active){
4347         // stop if:
4348         // - parameter change required
4349         // - it's disabled
4350         // - whitelist change required but used for advertisement filter policy
4351         // - resolving list modified
4352         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4353         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4354         if (advertising_change ||
4355             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4356             (advertising_uses_whitelist & whitelist_modification_pending) ||
4357             resolving_list_modification_pending) {
4358 
4359             advertising_stop = true;
4360         }
4361     }
4362 #endif
4363 
4364 
4365     // Phase 2: stop everything that should be off during modifications
4366 
4367 #ifdef ENABLE_LE_CENTRAL
4368     if (scanning_stop){
4369         hci_stack->le_scanning_active = false;
4370         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4371         return true;
4372     }
4373 #endif
4374 
4375 #ifdef ENABLE_LE_CENTRAL
4376     if (connecting_stop){
4377         hci_send_cmd(&hci_le_create_connection_cancel);
4378         return true;
4379     }
4380 #endif
4381 
4382 #ifdef ENABLE_LE_PERIPHERAL
4383     if (advertising_stop){
4384         hci_stack->le_advertisements_active = false;
4385         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4386         return true;
4387     }
4388 #endif
4389 
4390     // Phase 3: modify
4391 
4392 #ifdef ENABLE_LE_CENTRAL
4393     if (hci_stack->le_scanning_param_update){
4394         hci_stack->le_scanning_param_update = false;
4395         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4396                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4397         return true;
4398     }
4399 #endif
4400 
4401 #ifdef ENABLE_LE_PERIPHERAL
4402     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4403         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4404         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4405         hci_send_cmd(&hci_le_set_advertising_parameters,
4406                      hci_stack->le_advertisements_interval_min,
4407                      hci_stack->le_advertisements_interval_max,
4408                      hci_stack->le_advertisements_type,
4409                      hci_stack->le_advertisements_own_addr_type,
4410                      hci_stack->le_advertisements_direct_address_type,
4411                      hci_stack->le_advertisements_direct_address,
4412                      hci_stack->le_advertisements_channel_map,
4413                      hci_stack->le_advertisements_filter_policy);
4414         return true;
4415     }
4416     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4417         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4418         uint8_t adv_data_clean[31];
4419         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4420         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4421                      hci_stack->le_advertisements_data_len);
4422         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4423         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4424         return true;
4425     }
4426     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4427         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4428         uint8_t scan_data_clean[31];
4429         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4430         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4431                      hci_stack->le_scan_response_data_len);
4432         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4433         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4434         return true;
4435     }
4436 #endif
4437 
4438 
4439 #ifdef ENABLE_LE_CENTRAL
4440     // if connect with whitelist was active and is not cancelled yet, wait until next time
4441     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4442 #endif
4443 
4444     // LE Whitelist Management
4445     if (whitelist_modification_pending){
4446         // add/remove entries
4447         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4448         while (btstack_linked_list_iterator_has_next(&lit)){
4449             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4450 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4451 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4452 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4453 				return true;
4454 			}
4455             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4456 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4457                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4458                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4459                 return true;
4460             }
4461             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4462 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4463 				btstack_memory_whitelist_entry_free(entry);
4464             }
4465         }
4466     }
4467 
4468 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4469     // LE Resolving List Management
4470     if (resolving_list_supported) {
4471 		uint16_t i;
4472 		switch (hci_stack->le_resolving_list_state) {
4473 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4474 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4475 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4476 				return true;
4477 			case LE_RESOLVING_LIST_READ_SIZE:
4478 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4479 				hci_send_cmd(&hci_le_read_resolving_list_size);
4480 				return true;
4481 			case LE_RESOLVING_LIST_SEND_CLEAR:
4482 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4483 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4484 							  sizeof(hci_stack->le_resolving_list_add_entries));
4485 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4486 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4487 				hci_send_cmd(&hci_le_clear_resolving_list);
4488 				return true;
4489 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4490 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4491 					uint8_t offset = i >> 3;
4492 					uint8_t mask = 1 << (i & 7);
4493 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4494 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4495 					bd_addr_t peer_identity_addreses;
4496 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4497 					sm_key_t peer_irk;
4498 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4499 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4500 
4501 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4502 					// trigger whitelist entry 'update' (work around for controller bug)
4503 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4504 					while (btstack_linked_list_iterator_has_next(&lit)) {
4505 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4506 						if (entry->address_type != peer_identity_addr_type) continue;
4507 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4508 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4509 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4510 					}
4511 #endif
4512 
4513 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4514 								 peer_identity_addreses);
4515 					return true;
4516 				}
4517 
4518 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4519 
4520 				/* fall through */
4521 
4522 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4523 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4524 					uint8_t offset = i >> 3;
4525 					uint8_t mask = 1 << (i & 7);
4526 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4527 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4528 					bd_addr_t peer_identity_addreses;
4529 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4530 					sm_key_t peer_irk;
4531 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4532 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4533 					const uint8_t *local_irk = gap_get_persistent_irk();
4534 					// command uses format specifier 'P' that stores 16-byte value without flip
4535 					uint8_t local_irk_flipped[16];
4536 					uint8_t peer_irk_flipped[16];
4537 					reverse_128(local_irk, local_irk_flipped);
4538 					reverse_128(peer_irk, peer_irk_flipped);
4539 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4540 								 peer_irk_flipped, local_irk_flipped);
4541 					return true;
4542 				}
4543 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4544 				break;
4545 
4546 			default:
4547 				break;
4548 		}
4549 	}
4550     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4551 #endif
4552 
4553     // Phase 4: restore state
4554 
4555 #ifdef ENABLE_LE_CENTRAL
4556     // re-start scanning
4557     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4558         hci_stack->le_scanning_active = true;
4559         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4560         return true;
4561     }
4562 #endif
4563 
4564 #ifdef ENABLE_LE_CENTRAL
4565     // re-start connecting
4566     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4567         bd_addr_t null_addr;
4568         memset(null_addr, 0, 6);
4569         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4570         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4571         hci_send_cmd(&hci_le_create_connection,
4572                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4573                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4574                      1,         // use whitelist
4575                      0,         // peer address type
4576                      null_addr, // peer bd addr
4577                      hci_stack->le_connection_own_addr_type,   // our addr type:
4578                      hci_stack->le_connection_interval_min,    // conn interval min
4579                      hci_stack->le_connection_interval_max,    // conn interval max
4580                      hci_stack->le_connection_latency,         // conn latency
4581                      hci_stack->le_supervision_timeout,        // conn latency
4582                      hci_stack->le_minimum_ce_length,          // min ce length
4583                      hci_stack->le_maximum_ce_length           // max ce length
4584         );
4585         return true;
4586     }
4587 #endif
4588 
4589 #ifdef ENABLE_LE_PERIPHERAL
4590     // re-start advertising
4591     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4592         // check if advertisements should be enabled given
4593         hci_stack->le_advertisements_active = true;
4594         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4595         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4596         return true;
4597     }
4598 #endif
4599 
4600     return false;
4601 }
4602 #endif
4603 
4604 static bool hci_run_general_pending_commands(void){
4605     btstack_linked_item_t * it;
4606     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4607         hci_connection_t * connection = (hci_connection_t *) it;
4608 
4609         switch(connection->state){
4610             case SEND_CREATE_CONNECTION:
4611                 switch(connection->address_type){
4612 #ifdef ENABLE_CLASSIC
4613                     case BD_ADDR_TYPE_ACL:
4614                         log_info("sending hci_create_connection");
4615                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4616                         break;
4617 #endif
4618                     default:
4619 #ifdef ENABLE_BLE
4620 #ifdef ENABLE_LE_CENTRAL
4621                         log_info("sending hci_le_create_connection");
4622                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4623                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4624                         hci_send_cmd(&hci_le_create_connection,
4625                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4626                                      hci_stack->le_connection_scan_window,      // conn scan windows
4627                                      0,         // don't use whitelist
4628                                      connection->address_type, // peer address type
4629                                      connection->address,      // peer bd addr
4630                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4631                                      hci_stack->le_connection_interval_min,    // conn interval min
4632                                      hci_stack->le_connection_interval_max,    // conn interval max
4633                                      hci_stack->le_connection_latency,         // conn latency
4634                                      hci_stack->le_supervision_timeout,        // conn latency
4635                                      hci_stack->le_minimum_ce_length,          // min ce length
4636                                      hci_stack->le_maximum_ce_length          // max ce length
4637                         );
4638                         connection->state = SENT_CREATE_CONNECTION;
4639 #endif
4640 #endif
4641                         break;
4642                 }
4643                 return true;
4644 
4645 #ifdef ENABLE_CLASSIC
4646             case RECEIVED_CONNECTION_REQUEST:
4647                 connection->role  = HCI_ROLE_SLAVE;
4648                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4649                     log_info("sending hci_accept_connection_request");
4650                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4651                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4652                 }
4653                 return true;
4654 #endif
4655 
4656 #ifdef ENABLE_BLE
4657 #ifdef ENABLE_LE_CENTRAL
4658             case SEND_CANCEL_CONNECTION:
4659                 connection->state = SENT_CANCEL_CONNECTION;
4660                 hci_send_cmd(&hci_le_create_connection_cancel);
4661                 return true;
4662 #endif
4663 #endif
4664             case SEND_DISCONNECT:
4665                 connection->state = SENT_DISCONNECT;
4666                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4667                 return true;
4668 
4669             default:
4670                 break;
4671         }
4672 
4673         // no further commands if connection is about to get shut down
4674         if (connection->state == SENT_DISCONNECT) continue;
4675 
4676         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4677             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4678             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4679             return true;
4680         }
4681 
4682 #ifdef ENABLE_CLASSIC
4683 
4684         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4685             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4686             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4687             return true;
4688         }
4689 
4690         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4691             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4692             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4693             return true;
4694         }
4695 
4696         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4697             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4698             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4699             return true;
4700         }
4701 
4702         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4703             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4704             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4705             return true;
4706         }
4707 
4708         // Handling link key request requires remote supported features
4709         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4710             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4711             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4712 
4713             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4714             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4715             if (have_link_key && security_level_sufficient){
4716                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4717             } else {
4718                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4719             }
4720             return true;
4721         }
4722 
4723         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4724             log_info("denying to pin request");
4725             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4726             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4727             return true;
4728         }
4729 
4730         // security assessment requires remote features
4731         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4732             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4733             hci_ssp_assess_security_on_io_cap_request(connection);
4734             // 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
4735         }
4736 
4737         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4738             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4739             // set authentication requirements:
4740             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4741             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4742             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4743             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4744                 authreq |= 1;
4745             }
4746             bool bonding = hci_stack->bondable;
4747             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4748                 // if we have received IO Cap Response, we're in responder role
4749                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4750                 if (bonding && !remote_bonding){
4751                     log_info("Remote not bonding, dropping local flag");
4752                     bonding = false;
4753                 }
4754             }
4755             if (bonding){
4756                 if (connection->bonding_flags & BONDING_DEDICATED){
4757                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4758                 } else {
4759                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4760                 }
4761             }
4762             uint8_t have_oob_data = 0;
4763 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4764             if (connection->classic_oob_c_192 != NULL){
4765                     have_oob_data |= 1;
4766             }
4767             if (connection->classic_oob_c_256 != NULL){
4768                 have_oob_data |= 2;
4769             }
4770 #endif
4771             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4772             return true;
4773         }
4774 
4775         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4776             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4777             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4778             return true;
4779         }
4780 
4781 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4782         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4783             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4784             const uint8_t zero[16] = { 0 };
4785             const uint8_t * r_192 = zero;
4786             const uint8_t * c_192 = zero;
4787             const uint8_t * r_256 = zero;
4788             const uint8_t * c_256 = zero;
4789             // verify P-256 OOB
4790             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4791                 c_256 = connection->classic_oob_c_256;
4792                 if (connection->classic_oob_r_256 != NULL) {
4793                     r_256 = connection->classic_oob_r_256;
4794                 }
4795             }
4796             // verify P-192 OOB
4797             if ((connection->classic_oob_c_192 != NULL)) {
4798                 c_192 = connection->classic_oob_c_192;
4799                 if (connection->classic_oob_r_192 != NULL) {
4800                     r_192 = connection->classic_oob_r_192;
4801                 }
4802             }
4803 
4804             // assess security
4805             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4806             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4807             if (need_level_4 && !can_reach_level_4){
4808                 log_info("Level 4 required, but not possible -> abort");
4809                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4810                 // send oob negative reply
4811                 c_256 = NULL;
4812                 c_192 = NULL;
4813             }
4814 
4815             // Reply
4816             if (c_256 != zero) {
4817                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4818             } else if (c_192 != zero){
4819                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4820             } else {
4821                 hci_stack->classic_oob_con_handle = connection->con_handle;
4822                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4823             }
4824             return true;
4825         }
4826 #endif
4827 
4828         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4829             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4830             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4831             return true;
4832         }
4833 
4834         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4835             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4836             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4837             return true;
4838         }
4839 
4840         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4841             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4842             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4843             return true;
4844         }
4845 
4846         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4847             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4848             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4849             connection->state = SENT_DISCONNECT;
4850             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4851             return true;
4852         }
4853 
4854         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4855             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4856             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4857             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4858             return true;
4859         }
4860 
4861         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4862             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4863             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4864             return true;
4865         }
4866         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4867             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4868             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4869             return true;
4870         }
4871 #endif
4872 
4873         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4874             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4875 #ifdef ENABLE_CLASSIC
4876             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4877 #endif
4878             if (connection->state != SENT_DISCONNECT){
4879                 connection->state = SENT_DISCONNECT;
4880                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4881                 return true;
4882             }
4883         }
4884 
4885 #ifdef ENABLE_CLASSIC
4886         uint16_t sniff_min_interval;
4887         switch (connection->sniff_min_interval){
4888             case 0:
4889                 break;
4890             case 0xffff:
4891                 connection->sniff_min_interval = 0;
4892                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4893                 return true;
4894             default:
4895                 sniff_min_interval = connection->sniff_min_interval;
4896                 connection->sniff_min_interval = 0;
4897                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4898                 return true;
4899         }
4900 
4901         if (connection->sniff_subrating_max_latency != 0xffff){
4902             uint16_t max_latency = connection->sniff_subrating_max_latency;
4903             connection->sniff_subrating_max_latency = 0;
4904             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4905             return true;
4906         }
4907 
4908         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4909             uint8_t service_type = (uint8_t) connection->qos_service_type;
4910             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4911             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);
4912             return true;
4913         }
4914 
4915         if (connection->request_role != HCI_ROLE_INVALID){
4916             hci_role_t role = connection->request_role;
4917             connection->request_role = HCI_ROLE_INVALID;
4918             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4919             return true;
4920         }
4921 #endif
4922 
4923 #ifdef ENABLE_BLE
4924         switch (connection->le_con_parameter_update_state){
4925             // response to L2CAP CON PARAMETER UPDATE REQUEST
4926             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4927                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4928                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4929                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4930                              0x0000, 0xffff);
4931                 return true;
4932             case CON_PARAMETER_UPDATE_REPLY:
4933                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4934                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4935                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4936                              0x0000, 0xffff);
4937                 return true;
4938             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4939                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4940                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4941                 return true;
4942             default:
4943                 break;
4944         }
4945         if (connection->le_phy_update_all_phys != 0xffu){
4946             uint8_t all_phys = connection->le_phy_update_all_phys;
4947             connection->le_phy_update_all_phys = 0xff;
4948             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);
4949             return true;
4950         }
4951 #endif
4952     }
4953     return false;
4954 }
4955 
4956 static void hci_run(void){
4957 
4958     bool done;
4959 
4960     // send continuation fragments first, as they block the prepared packet buffer
4961     done = hci_run_acl_fragments();
4962     if (done) return;
4963 
4964 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4965     // send host num completed packets next as they don't require num_cmd_packets > 0
4966     if (!hci_can_send_comand_packet_transport()) return;
4967     if (hci_stack->host_completed_packets){
4968         hci_host_num_completed_packets();
4969         return;
4970     }
4971 #endif
4972 
4973     if (!hci_can_send_command_packet_now()) return;
4974 
4975     // global/non-connection oriented commands
4976 
4977 
4978 #ifdef ENABLE_CLASSIC
4979     // general gap classic
4980     done = hci_run_general_gap_classic();
4981     if (done) return;
4982 #endif
4983 
4984 #ifdef ENABLE_BLE
4985     // general gap le
4986     done = hci_run_general_gap_le();
4987     if (done) return;
4988 #endif
4989 
4990     // send pending HCI commands
4991     done = hci_run_general_pending_commands();
4992     if (done) return;
4993 
4994     // stack state sub statemachines
4995     hci_connection_t * connection;
4996     switch (hci_stack->state){
4997         case HCI_STATE_INITIALIZING:
4998             hci_initializing_run();
4999             break;
5000 
5001         case HCI_STATE_HALTING:
5002 
5003             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5004             switch (hci_stack->substate){
5005                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5006                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5007 
5008 #ifdef ENABLE_BLE
5009 #ifdef ENABLE_LE_CENTRAL
5010                     // free whitelist entries
5011                     {
5012                         btstack_linked_list_iterator_t lit;
5013                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5014                         while (btstack_linked_list_iterator_has_next(&lit)){
5015                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5016                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5017                             btstack_memory_whitelist_entry_free(entry);
5018                         }
5019                     }
5020 #endif
5021 #endif
5022                     // close all open connections
5023                     connection =  (hci_connection_t *) hci_stack->connections;
5024                     if (connection){
5025                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5026                         if (!hci_can_send_command_packet_now()) return;
5027 
5028                         // check state
5029                         if (connection->state == SENT_DISCONNECT) return;
5030                         connection->state = SENT_DISCONNECT;
5031 
5032                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5033 
5034                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5035                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5036 
5037                         // ... which would be ignored anyway as we shutdown (free) the connection now
5038                         hci_shutdown_connection(connection);
5039 
5040                         // finally, send the disconnect command
5041                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5042                         return;
5043                     }
5044 
5045                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5046                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5047                         log_info("HCI_STATE_HALTING: wait 50 ms");
5048                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5049                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5050                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5051                         btstack_run_loop_add_timer(&hci_stack->timeout);
5052                         break;
5053                     }
5054 
5055                     /* fall through */
5056 
5057                 case HCI_HALTING_CLOSE:
5058                     log_info("HCI_STATE_HALTING, calling off");
5059 
5060                     // switch mode
5061                     hci_power_control_off();
5062 
5063                     log_info("HCI_STATE_HALTING, emitting state");
5064                     hci_emit_state();
5065                     log_info("HCI_STATE_HALTING, done");
5066                     break;
5067 
5068                 case HCI_HALTING_W4_TIMER:
5069                     // keep waiting
5070 
5071                     break;
5072                 default:
5073                     break;
5074             }
5075 
5076             break;
5077 
5078         case HCI_STATE_FALLING_ASLEEP:
5079             switch(hci_stack->substate) {
5080                 case HCI_FALLING_ASLEEP_DISCONNECT:
5081                     log_info("HCI_STATE_FALLING_ASLEEP");
5082                     // close all open connections
5083                     connection =  (hci_connection_t *) hci_stack->connections;
5084                     if (connection){
5085 
5086                         // send disconnect
5087                         if (!hci_can_send_command_packet_now()) return;
5088 
5089                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5090                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5091 
5092                         // send disconnected event right away - causes higher layer connections to get closed, too.
5093                         hci_shutdown_connection(connection);
5094                         return;
5095                     }
5096 
5097                     if (hci_classic_supported()){
5098                         // disable page and inquiry scan
5099                         if (!hci_can_send_command_packet_now()) return;
5100 
5101                         log_info("HCI_STATE_HALTING, disabling inq scans");
5102                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5103 
5104                         // continue in next sub state
5105                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5106                         break;
5107                     }
5108 
5109                     /* fall through */
5110 
5111                 case HCI_FALLING_ASLEEP_COMPLETE:
5112                     log_info("HCI_STATE_HALTING, calling sleep");
5113                     // switch mode
5114                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5115                     hci_emit_state();
5116                     break;
5117 
5118                 default:
5119                     break;
5120             }
5121             break;
5122 
5123         default:
5124             break;
5125     }
5126 }
5127 
5128 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5129     // house-keeping
5130 
5131 #ifdef ENABLE_CLASSIC
5132     bd_addr_t addr;
5133     hci_connection_t * conn;
5134 #endif
5135 #ifdef ENABLE_LE_CENTRAL
5136     uint8_t initiator_filter_policy;
5137 #endif
5138 
5139     uint16_t opcode = little_endian_read_16(packet, 0);
5140     switch (opcode) {
5141         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5142             hci_stack->loopback_mode = packet[3];
5143             break;
5144 
5145 #ifdef ENABLE_CLASSIC
5146         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5147             reverse_bd_addr(&packet[3], addr);
5148             log_info("Create_connection to %s", bd_addr_to_str(addr));
5149 
5150             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5151             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5152                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5153                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5154             }
5155 
5156             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5157             if (!conn) {
5158                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5159                 if (!conn) {
5160                     // notify client that alloc failed
5161                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5162                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5163                 }
5164                 conn->state = SEND_CREATE_CONNECTION;
5165                 conn->role  = HCI_ROLE_MASTER;
5166             }
5167 
5168             conn->con_handle = HCI_CON_HANDLE_INVALID;
5169             conn->role = HCI_ROLE_INVALID;
5170 
5171             log_info("conn state %u", conn->state);
5172             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5173             switch (conn->state) {
5174                 // if connection active exists
5175                 case OPEN:
5176                     // and OPEN, emit connection complete command
5177                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5178                     // packet not sent to controller
5179                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5180                 case RECEIVED_DISCONNECTION_COMPLETE:
5181                     // create connection triggered in disconnect complete event, let's do it now
5182                     break;
5183                 case SEND_CREATE_CONNECTION:
5184                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5185                     break;
5186                 default:
5187                     // otherwise, just ignore as it is already in the open process
5188                     // packet not sent to controller
5189                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5190             }
5191             conn->state = SENT_CREATE_CONNECTION;
5192 
5193             // track outgoing connection
5194             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5195             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5196             break;
5197         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5198             if (hci_stack->link_key_db) {
5199                 reverse_bd_addr(&packet[3], addr);
5200                 hci_stack->link_key_db->delete_link_key(addr);
5201             }
5202             break;
5203 
5204 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5205         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5206             // setup_synchronous_connection? Voice setting at offset 22
5207             // TODO: compare to current setting if sco connection already active
5208             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5209             break;
5210         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5211             // accept_synchronus_connection? Voice setting at offset 18
5212             // TODO: compare to current setting if sco connection already active
5213             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5214             break;
5215 #endif
5216 #endif
5217 
5218 #ifdef ENABLE_BLE
5219         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5220             hci_stack->le_random_address_set = 1;
5221             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5222             break;
5223 #ifdef ENABLE_LE_PERIPHERAL
5224         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5225             hci_stack->le_advertisements_active = packet[3] != 0;
5226             break;
5227 #endif
5228 #ifdef ENABLE_LE_CENTRAL
5229         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5230             // white list used?
5231             initiator_filter_policy = packet[7];
5232             switch (initiator_filter_policy) {
5233                 case 0:
5234                     // whitelist not used
5235                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5236                     break;
5237                 case 1:
5238                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5239                     break;
5240                 default:
5241                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5242                     break;
5243             }
5244             // track outgoing connection
5245             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5246             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5247             break;
5248         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5249             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5250             break;
5251 #endif
5252 #endif
5253         default:
5254             break;
5255     }
5256 
5257     hci_stack->num_cmd_packets--;
5258 
5259     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5260     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5261     if (err != 0){
5262         return ERROR_CODE_HARDWARE_FAILURE;
5263     }
5264     return ERROR_CODE_SUCCESS;
5265 }
5266 
5267 // disconnect because of security block
5268 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5269     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5270     if (!connection) return;
5271     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5272 }
5273 
5274 
5275 // Configure Secure Simple Pairing
5276 
5277 #ifdef ENABLE_CLASSIC
5278 
5279 // enable will enable SSP during init
5280 void gap_ssp_set_enable(int enable){
5281     hci_stack->ssp_enable = enable;
5282 }
5283 
5284 static int hci_local_ssp_activated(void){
5285     return gap_ssp_supported() && hci_stack->ssp_enable;
5286 }
5287 
5288 // if set, BTstack will respond to io capability request using authentication requirement
5289 void gap_ssp_set_io_capability(int io_capability){
5290     hci_stack->ssp_io_capability = io_capability;
5291 }
5292 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5293     hci_stack->ssp_authentication_requirement = authentication_requirement;
5294 }
5295 
5296 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5297 void gap_ssp_set_auto_accept(int auto_accept){
5298     hci_stack->ssp_auto_accept = auto_accept;
5299 }
5300 
5301 void gap_secure_connections_enable(bool enable){
5302     hci_stack->secure_connections_enable = enable;
5303 }
5304 
5305 #endif
5306 
5307 // va_list part of hci_send_cmd
5308 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5309     if (!hci_can_send_command_packet_now()){
5310         log_error("hci_send_cmd called but cannot send packet now");
5311         return ERROR_CODE_COMMAND_DISALLOWED;
5312     }
5313 
5314     // for HCI INITIALIZATION
5315     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5316     hci_stack->last_cmd_opcode = cmd->opcode;
5317 
5318     hci_reserve_packet_buffer();
5319     uint8_t * packet = hci_stack->hci_packet_buffer;
5320     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5321     uint8_t status = hci_send_cmd_packet(packet, size);
5322 
5323     // release packet buffer on error or for synchronous transport implementations
5324     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5325         hci_release_packet_buffer();
5326         hci_emit_transport_packet_sent();
5327     }
5328 
5329     return status;
5330 }
5331 
5332 /**
5333  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5334  */
5335 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5336     va_list argptr;
5337     va_start(argptr, cmd);
5338     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5339     va_end(argptr);
5340     return status;
5341 }
5342 
5343 // Create various non-HCI events.
5344 // TODO: generalize, use table similar to hci_create_command
5345 
5346 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5347     // dump packet
5348     if (dump) {
5349         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5350     }
5351 
5352     // dispatch to all event handlers
5353     btstack_linked_list_iterator_t it;
5354     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5355     while (btstack_linked_list_iterator_has_next(&it)){
5356         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5357         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5358     }
5359 }
5360 
5361 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5362     if (!hci_stack->acl_packet_handler) return;
5363     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5364 }
5365 
5366 #ifdef ENABLE_CLASSIC
5367 static void hci_notify_if_sco_can_send_now(void){
5368     // notify SCO sender if waiting
5369     if (!hci_stack->sco_waiting_for_can_send_now) return;
5370     if (hci_can_send_sco_packet_now()){
5371         hci_stack->sco_waiting_for_can_send_now = 0;
5372         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5373         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5374         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5375     }
5376 }
5377 
5378 // parsing end emitting has been merged to reduce code size
5379 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5380     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5381 
5382     uint8_t * eir_data;
5383     ad_context_t context;
5384     const uint8_t * name;
5385     uint8_t         name_len;
5386 
5387     if (size < 3) return;
5388 
5389     int event_type = hci_event_packet_get_type(packet);
5390     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5391     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5392 
5393     switch (event_type){
5394         case HCI_EVENT_INQUIRY_RESULT:
5395         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5396             if (size != (3 + (num_responses * 14))) return;
5397             break;
5398         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5399             if (size != 257) return;
5400             if (num_responses != 1) return;
5401             break;
5402         default:
5403             return;
5404     }
5405 
5406     // event[1] is set at the end
5407     int i;
5408     for (i=0; i<num_responses;i++){
5409         memset(event, 0, sizeof(event));
5410         event[0] = GAP_EVENT_INQUIRY_RESULT;
5411         uint8_t event_size = 27;    // if name is not set by EIR
5412 
5413         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5414         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5415         (void)memcpy(&event[9],
5416                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5417                      3); // class of device
5418         (void)memcpy(&event[12],
5419                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5420                      2); // clock offset
5421 
5422         switch (event_type){
5423             case HCI_EVENT_INQUIRY_RESULT:
5424                 // 14,15,16,17 = 0, size 18
5425                 break;
5426             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5427                 event[14] = 1;
5428                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5429                 // 16,17 = 0, size 18
5430                 break;
5431             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5432                 event[14] = 1;
5433                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5434                 // EIR packets only contain a single inquiry response
5435                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5436                 name = NULL;
5437                 // Iterate over EIR data
5438                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5439                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5440                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5441                     const uint8_t * data = ad_iterator_get_data(&context);
5442                     // Prefer Complete Local Name over Shortened Local Name
5443                     switch (data_type){
5444                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5445                             if (name) continue;
5446                             /* fall through */
5447                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5448                             name = data;
5449                             name_len = data_size;
5450                             break;
5451                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5452                             if (data_size != 8) break;
5453                             event[16] = 1;
5454                             memcpy(&event[17], data, 8);
5455                             break;
5456                         default:
5457                             break;
5458                     }
5459                 }
5460                 if (name){
5461                     event[25] = 1;
5462                     // truncate name if needed
5463                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5464                     event[26] = len;
5465                     (void)memcpy(&event[27], name, len);
5466                     event_size += len;
5467                 }
5468                 break;
5469             default:
5470                 return;
5471         }
5472         event[1] = event_size - 2;
5473         hci_emit_event(event, event_size, 1);
5474     }
5475 }
5476 #endif
5477 
5478 void hci_emit_state(void){
5479     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5480     uint8_t event[3];
5481     event[0] = BTSTACK_EVENT_STATE;
5482     event[1] = sizeof(event) - 2u;
5483     event[2] = hci_stack->state;
5484     hci_emit_event(event, sizeof(event), 1);
5485 }
5486 
5487 #ifdef ENABLE_CLASSIC
5488 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5489     uint8_t event[13];
5490     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5491     event[1] = sizeof(event) - 2;
5492     event[2] = status;
5493     little_endian_store_16(event, 3, con_handle);
5494     reverse_bd_addr(address, &event[5]);
5495     event[11] = 1; // ACL connection
5496     event[12] = 0; // encryption disabled
5497     hci_emit_event(event, sizeof(event), 1);
5498 }
5499 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5500     if (disable_l2cap_timeouts) return;
5501     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5502     uint8_t event[4];
5503     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5504     event[1] = sizeof(event) - 2;
5505     little_endian_store_16(event, 2, conn->con_handle);
5506     hci_emit_event(event, sizeof(event), 1);
5507 }
5508 #endif
5509 
5510 #ifdef ENABLE_BLE
5511 #ifdef ENABLE_LE_CENTRAL
5512 static void hci_emit_le_connection_complete(uint8_t address_type, const bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5513     uint8_t event[21];
5514     event[0] = HCI_EVENT_LE_META;
5515     event[1] = sizeof(event) - 2u;
5516     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5517     event[3] = status;
5518     little_endian_store_16(event, 4, con_handle);
5519     event[6] = 0; // TODO: role
5520     event[7] = address_type;
5521     reverse_bd_addr(address, &event[8]);
5522     little_endian_store_16(event, 14, 0); // interval
5523     little_endian_store_16(event, 16, 0); // latency
5524     little_endian_store_16(event, 18, 0); // supervision timeout
5525     event[20] = 0; // master clock accuracy
5526     hci_emit_event(event, sizeof(event), 1);
5527 }
5528 #endif
5529 #endif
5530 
5531 static void hci_emit_transport_packet_sent(void){
5532     // notify upper stack that it might be possible to send again
5533     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5534     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5535 }
5536 
5537 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5538     uint8_t event[6];
5539     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5540     event[1] = sizeof(event) - 2u;
5541     event[2] = 0; // status = OK
5542     little_endian_store_16(event, 3, con_handle);
5543     event[5] = reason;
5544     hci_emit_event(event, sizeof(event), 1);
5545 }
5546 
5547 static void hci_emit_nr_connections_changed(void){
5548     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5549     uint8_t event[3];
5550     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5551     event[1] = sizeof(event) - 2u;
5552     event[2] = nr_hci_connections();
5553     hci_emit_event(event, sizeof(event), 1);
5554 }
5555 
5556 static void hci_emit_hci_open_failed(void){
5557     log_info("BTSTACK_EVENT_POWERON_FAILED");
5558     uint8_t event[2];
5559     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5560     event[1] = sizeof(event) - 2u;
5561     hci_emit_event(event, sizeof(event), 1);
5562 }
5563 
5564 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5565     log_info("hci_emit_dedicated_bonding_result %u ", status);
5566     uint8_t event[9];
5567     int pos = 0;
5568     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5569     event[pos++] = sizeof(event) - 2u;
5570     event[pos++] = status;
5571     reverse_bd_addr(address, &event[pos]);
5572     hci_emit_event(event, sizeof(event), 1);
5573 }
5574 
5575 
5576 #ifdef ENABLE_CLASSIC
5577 
5578 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5579     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5580     uint8_t event[5];
5581     int pos = 0;
5582     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5583     event[pos++] = sizeof(event) - 2;
5584     little_endian_store_16(event, 2, con_handle);
5585     pos += 2;
5586     event[pos++] = level;
5587     hci_emit_event(event, sizeof(event), 1);
5588 }
5589 
5590 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5591     if (!connection) return LEVEL_0;
5592     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5593     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5594     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5595     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5596     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5597     // LEVEL 4 always requires 128 bit encrytion key size
5598     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5599         security_level = LEVEL_3;
5600     }
5601     return security_level;
5602 }
5603 
5604 static void hci_emit_discoverable_enabled(uint8_t enabled){
5605     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5606     uint8_t event[3];
5607     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5608     event[1] = sizeof(event) - 2;
5609     event[2] = enabled;
5610     hci_emit_event(event, sizeof(event), 1);
5611 }
5612 
5613 // query if remote side supports eSCO
5614 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5615     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5616     if (!connection) return false;
5617     return (connection->remote_supported_features[0] & 1) != 0;
5618 }
5619 
5620 static bool hci_ssp_supported(hci_connection_t * connection){
5621     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5622     return (connection->bonding_flags & mask) == mask;
5623 }
5624 
5625 // query if remote side supports SSP
5626 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5627     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5628     if (!connection) return false;
5629     return hci_ssp_supported(connection) ? 1 : 0;
5630 }
5631 
5632 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5633     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5634 }
5635 
5636 // GAP API
5637 /**
5638  * @bbrief enable/disable bonding. default is enabled
5639  * @praram enabled
5640  */
5641 void gap_set_bondable_mode(int enable){
5642     hci_stack->bondable = enable ? 1 : 0;
5643 }
5644 /**
5645  * @brief Get bondable mode.
5646  * @return 1 if bondable
5647  */
5648 int gap_get_bondable_mode(void){
5649     return hci_stack->bondable;
5650 }
5651 
5652 /**
5653  * @brief map link keys to security levels
5654  */
5655 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5656     switch (link_key_type){
5657         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5658             return LEVEL_4;
5659         case COMBINATION_KEY:
5660         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5661             return LEVEL_3;
5662         default:
5663             return LEVEL_2;
5664     }
5665 }
5666 
5667 /**
5668  * @brief map link keys to secure connection yes/no
5669  */
5670 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5671     switch (link_key_type){
5672         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5673         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5674             return 1;
5675         default:
5676             return 0;
5677     }
5678 }
5679 
5680 /**
5681  * @brief map link keys to authenticated
5682  */
5683 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5684     switch (link_key_type){
5685         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5686         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5687             return 1;
5688         default:
5689             return 0;
5690     }
5691 }
5692 
5693 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5694     log_info("gap_mitm_protection_required_for_security_level %u", level);
5695     return level > LEVEL_2;
5696 }
5697 
5698 /**
5699  * @brief get current security level
5700  */
5701 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5702     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5703     if (!connection) return LEVEL_0;
5704     return gap_security_level_for_connection(connection);
5705 }
5706 
5707 /**
5708  * @brief request connection to device to
5709  * @result GAP_AUTHENTICATION_RESULT
5710  */
5711 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5712     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5713     if (!connection){
5714         hci_emit_security_level(con_handle, LEVEL_0);
5715         return;
5716     }
5717 
5718     btstack_assert(hci_is_le_connection(connection) == false);
5719 
5720     // 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)
5721     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5722     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5723         requested_level = LEVEL_4;
5724     }
5725 
5726     gap_security_level_t current_level = gap_security_level(con_handle);
5727     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5728         requested_level, connection->requested_security_level, current_level);
5729 
5730     // authentication active if authentication request was sent or planned level > 0
5731     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5732     if (authentication_active){
5733         // authentication already active
5734         if (connection->requested_security_level < requested_level){
5735             // increase requested level as new level is higher
5736             // TODO: handle re-authentication when done
5737             connection->requested_security_level = requested_level;
5738         }
5739     } else {
5740         // no request active, notify if security sufficient
5741         if (requested_level <= current_level){
5742             hci_emit_security_level(con_handle, current_level);
5743             return;
5744         }
5745 
5746         // store request
5747         connection->requested_security_level = requested_level;
5748 
5749         // start to authenticate connection
5750         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5751         hci_run();
5752     }
5753 }
5754 
5755 /**
5756  * @brief start dedicated bonding with device. disconnect after bonding
5757  * @param device
5758  * @param request MITM protection
5759  * @result GAP_DEDICATED_BONDING_COMPLETE
5760  */
5761 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5762 
5763     // create connection state machine
5764     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5765 
5766     if (!connection){
5767         return BTSTACK_MEMORY_ALLOC_FAILED;
5768     }
5769 
5770     // delete linkn key
5771     gap_drop_link_key_for_bd_addr(device);
5772 
5773     // configure LEVEL_2/3, dedicated bonding
5774     connection->state = SEND_CREATE_CONNECTION;
5775     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5776     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5777     connection->bonding_flags = BONDING_DEDICATED;
5778 
5779     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5780 
5781     // handle: connnection failure (connection complete != ok)
5782     // handle: authentication failure
5783     // handle: disconnect on done
5784 
5785     hci_run();
5786 
5787     return 0;
5788 }
5789 
5790 void gap_set_local_name(const char * local_name){
5791     hci_stack->local_name = local_name;
5792     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5793     // also update EIR if not set by user
5794     if (hci_stack->eir_data == NULL){
5795         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5796     }
5797     hci_run();
5798 }
5799 #endif
5800 
5801 
5802 #ifdef ENABLE_BLE
5803 
5804 #ifdef ENABLE_LE_CENTRAL
5805 void gap_start_scan(void){
5806     hci_stack->le_scanning_enabled = true;
5807     hci_run();
5808 }
5809 
5810 void gap_stop_scan(void){
5811     hci_stack->le_scanning_enabled = false;
5812     hci_run();
5813 }
5814 
5815 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5816     hci_stack->le_scan_type          = scan_type;
5817     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5818     hci_stack->le_scan_interval      = scan_interval;
5819     hci_stack->le_scan_window        = scan_window;
5820     hci_stack->le_scanning_param_update = true;
5821     hci_run();
5822 }
5823 
5824 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5825     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5826 }
5827 
5828 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5829     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5830     if (!conn){
5831         // disallow if le connection is already outgoing
5832         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5833             log_error("le connection already active");
5834             return ERROR_CODE_COMMAND_DISALLOWED;
5835         }
5836 
5837         log_info("gap_connect: no connection exists yet, creating context");
5838         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5839         if (!conn){
5840             // notify client that alloc failed
5841             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5842             log_info("gap_connect: failed to alloc hci_connection_t");
5843             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5844         }
5845 
5846         // set le connecting state
5847         if (hci_is_le_connection_type(addr_type)){
5848             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5849         }
5850 
5851         conn->state = SEND_CREATE_CONNECTION;
5852         log_info("gap_connect: send create connection next");
5853         hci_run();
5854         return ERROR_CODE_SUCCESS;
5855     }
5856 
5857     if (!hci_is_le_connection(conn) ||
5858         (conn->state == SEND_CREATE_CONNECTION) ||
5859         (conn->state == SENT_CREATE_CONNECTION)) {
5860         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5861         log_error("gap_connect: classic connection or connect is already being created");
5862         return GATT_CLIENT_IN_WRONG_STATE;
5863     }
5864 
5865     // check if connection was just disconnected
5866     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5867         log_info("gap_connect: send create connection (again)");
5868         conn->state = SEND_CREATE_CONNECTION;
5869         hci_run();
5870         return ERROR_CODE_SUCCESS;
5871     }
5872 
5873     log_info("gap_connect: context exists with state %u", conn->state);
5874     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5875     hci_run();
5876     return ERROR_CODE_SUCCESS;
5877 }
5878 
5879 // @assumption: only a single outgoing LE Connection exists
5880 static hci_connection_t * gap_get_outgoing_connection(void){
5881     btstack_linked_item_t *it;
5882     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5883         hci_connection_t * conn = (hci_connection_t *) it;
5884         if (!hci_is_le_connection(conn)) continue;
5885         switch (conn->state){
5886             case SEND_CREATE_CONNECTION:
5887             case SENT_CREATE_CONNECTION:
5888             case SENT_CANCEL_CONNECTION:
5889                 return conn;
5890             default:
5891                 break;
5892         };
5893     }
5894     return NULL;
5895 }
5896 
5897 uint8_t gap_connect_cancel(void){
5898     hci_connection_t * conn = gap_get_outgoing_connection();
5899     if (!conn) return 0;
5900     switch (conn->state){
5901         case SEND_CREATE_CONNECTION:
5902             // skip sending create connection and emit event instead
5903             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5904             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5905             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5906             btstack_memory_hci_connection_free( conn );
5907             break;
5908         case SENT_CREATE_CONNECTION:
5909             // request to send cancel connection
5910             conn->state = SEND_CANCEL_CONNECTION;
5911             hci_run();
5912             break;
5913         default:
5914             break;
5915     }
5916     return 0;
5917 }
5918 #endif
5919 
5920 #ifdef ENABLE_LE_CENTRAL
5921 /**
5922  * @brief Set connection parameters for outgoing connections
5923  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5924  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5925  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5926  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5927  * @param conn_latency, default: 4
5928  * @param supervision_timeout (unit: 10ms), default: 720 ms
5929  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5930  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5931  */
5932 
5933 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5934     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5935     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5936     hci_stack->le_connection_scan_interval = conn_scan_interval;
5937     hci_stack->le_connection_scan_window = conn_scan_window;
5938     hci_stack->le_connection_interval_min = conn_interval_min;
5939     hci_stack->le_connection_interval_max = conn_interval_max;
5940     hci_stack->le_connection_latency = conn_latency;
5941     hci_stack->le_supervision_timeout = supervision_timeout;
5942     hci_stack->le_minimum_ce_length = min_ce_length;
5943     hci_stack->le_maximum_ce_length = max_ce_length;
5944 }
5945 #endif
5946 
5947 /**
5948  * @brief Updates the connection parameters for a given LE connection
5949  * @param handle
5950  * @param conn_interval_min (unit: 1.25ms)
5951  * @param conn_interval_max (unit: 1.25ms)
5952  * @param conn_latency
5953  * @param supervision_timeout (unit: 10ms)
5954  * @returns 0 if ok
5955  */
5956 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5957     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5958     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5959     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5960     connection->le_conn_interval_min = conn_interval_min;
5961     connection->le_conn_interval_max = conn_interval_max;
5962     connection->le_conn_latency = conn_latency;
5963     connection->le_supervision_timeout = supervision_timeout;
5964     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5965     hci_run();
5966     return 0;
5967 }
5968 
5969 /**
5970  * @brief Request an update of the connection parameter for a given LE connection
5971  * @param handle
5972  * @param conn_interval_min (unit: 1.25ms)
5973  * @param conn_interval_max (unit: 1.25ms)
5974  * @param conn_latency
5975  * @param supervision_timeout (unit: 10ms)
5976  * @returns 0 if ok
5977  */
5978 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5979     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5980     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5981     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5982     connection->le_conn_interval_min = conn_interval_min;
5983     connection->le_conn_interval_max = conn_interval_max;
5984     connection->le_conn_latency = conn_latency;
5985     connection->le_supervision_timeout = supervision_timeout;
5986     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5987     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5988     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5989     return 0;
5990 }
5991 
5992 #ifdef ENABLE_LE_PERIPHERAL
5993 
5994 /**
5995  * @brief Set Advertisement Data
5996  * @param advertising_data_length
5997  * @param advertising_data (max 31 octets)
5998  * @note data is not copied, pointer has to stay valid
5999  */
6000 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6001     hci_stack->le_advertisements_data_len = advertising_data_length;
6002     hci_stack->le_advertisements_data = advertising_data;
6003     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6004     hci_run();
6005 }
6006 
6007 /**
6008  * @brief Set Scan Response Data
6009  * @param advertising_data_length
6010  * @param advertising_data (max 31 octets)
6011  * @note data is not copied, pointer has to stay valid
6012  */
6013 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6014     hci_stack->le_scan_response_data_len = scan_response_data_length;
6015     hci_stack->le_scan_response_data = scan_response_data;
6016     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6017     hci_run();
6018 }
6019 
6020 /**
6021  * @brief Set Advertisement Parameters
6022  * @param adv_int_min
6023  * @param adv_int_max
6024  * @param adv_type
6025  * @param direct_address_type
6026  * @param direct_address
6027  * @param channel_map
6028  * @param filter_policy
6029  *
6030  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6031  */
6032  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6033     uint8_t direct_address_typ, bd_addr_t direct_address,
6034     uint8_t channel_map, uint8_t filter_policy) {
6035 
6036     hci_stack->le_advertisements_interval_min = adv_int_min;
6037     hci_stack->le_advertisements_interval_max = adv_int_max;
6038     hci_stack->le_advertisements_type = adv_type;
6039     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6040     hci_stack->le_advertisements_channel_map = channel_map;
6041     hci_stack->le_advertisements_filter_policy = filter_policy;
6042     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6043                  6);
6044 
6045     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6046     hci_run();
6047  }
6048 
6049 /**
6050  * @brief Enable/Disable Advertisements
6051  * @param enabled
6052  */
6053 void gap_advertisements_enable(int enabled){
6054     hci_stack->le_advertisements_enabled = enabled != 0;
6055     hci_update_advertisements_enabled_for_current_roles();
6056     hci_run();
6057 }
6058 
6059 #endif
6060 
6061 void hci_le_set_own_address_type(uint8_t own_address_type){
6062     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6063     if (own_address_type == hci_stack->le_own_addr_type) return;
6064     hci_stack->le_own_addr_type = own_address_type;
6065 
6066 #ifdef ENABLE_LE_PERIPHERAL
6067     // update advertisement parameters, too
6068     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6069     hci_run();
6070 #endif
6071 #ifdef ENABLE_LE_CENTRAL
6072     // note: we don't update scan parameters or modify ongoing connection attempts
6073 #endif
6074 }
6075 
6076 #endif
6077 
6078 uint8_t gap_disconnect(hci_con_handle_t handle){
6079     hci_connection_t * conn = hci_connection_for_handle(handle);
6080     if (!conn){
6081         hci_emit_disconnection_complete(handle, 0);
6082         return 0;
6083     }
6084     // ignore if already disconnected
6085     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6086         return 0;
6087     }
6088     conn->state = SEND_DISCONNECT;
6089     hci_run();
6090     return 0;
6091 }
6092 
6093 int gap_read_rssi(hci_con_handle_t con_handle){
6094     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6095     if (hci_connection == NULL) return 0;
6096     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6097     hci_run();
6098     return 1;
6099 }
6100 
6101 /**
6102  * @brief Get connection type
6103  * @param con_handle
6104  * @result connection_type
6105  */
6106 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6107     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6108     if (!conn) return GAP_CONNECTION_INVALID;
6109     switch (conn->address_type){
6110         case BD_ADDR_TYPE_LE_PUBLIC:
6111         case BD_ADDR_TYPE_LE_RANDOM:
6112             return GAP_CONNECTION_LE;
6113         case BD_ADDR_TYPE_SCO:
6114             return GAP_CONNECTION_SCO;
6115         case BD_ADDR_TYPE_ACL:
6116             return GAP_CONNECTION_ACL;
6117         default:
6118             return GAP_CONNECTION_INVALID;
6119     }
6120 }
6121 
6122 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6123     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6124     if (!conn) return HCI_ROLE_INVALID;
6125     return (hci_role_t) conn->role;
6126 }
6127 
6128 
6129 #ifdef ENABLE_CLASSIC
6130 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6131     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6132     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6133     conn->request_role = role;
6134     hci_run();
6135     return ERROR_CODE_SUCCESS;
6136 }
6137 #endif
6138 
6139 #ifdef ENABLE_BLE
6140 
6141 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){
6142     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6143     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6144 
6145     conn->le_phy_update_all_phys    = all_phys;
6146     conn->le_phy_update_tx_phys     = tx_phys;
6147     conn->le_phy_update_rx_phys     = rx_phys;
6148     conn->le_phy_update_phy_options = phy_options;
6149 
6150     hci_run();
6151 
6152     return 0;
6153 }
6154 
6155 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6156     // check if already in list
6157     btstack_linked_list_iterator_t it;
6158     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6159     while (btstack_linked_list_iterator_has_next(&it)) {
6160         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6161         if (entry->address_type != address_type) {
6162             continue;
6163         }
6164         if (memcmp(entry->address, address, 6) != 0) {
6165             continue;
6166         }
6167 		// disallow if already scheduled to add
6168 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6169 			return ERROR_CODE_COMMAND_DISALLOWED;
6170 		}
6171 		// still on controller, but scheduled to remove -> re-add
6172 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6173 		return ERROR_CODE_SUCCESS;
6174     }
6175     // alloc and add to list
6176     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6177     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6178     entry->address_type = address_type;
6179     (void)memcpy(entry->address, address, 6);
6180     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6181     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6182     return ERROR_CODE_SUCCESS;
6183 }
6184 
6185 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6186     btstack_linked_list_iterator_t it;
6187     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6188     while (btstack_linked_list_iterator_has_next(&it)){
6189         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6190         if (entry->address_type != address_type) {
6191             continue;
6192         }
6193         if (memcmp(entry->address, address, 6) != 0) {
6194             continue;
6195         }
6196         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6197             // remove from controller if already present
6198             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6199         }  else {
6200             // directly remove entry from whitelist
6201             btstack_linked_list_iterator_remove(&it);
6202             btstack_memory_whitelist_entry_free(entry);
6203         }
6204         return ERROR_CODE_SUCCESS;
6205     }
6206     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6207 }
6208 
6209 static void hci_whitelist_clear(void){
6210     btstack_linked_list_iterator_t it;
6211     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6212     while (btstack_linked_list_iterator_has_next(&it)){
6213         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6214         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6215             // remove from controller if already present
6216             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6217             continue;
6218         }
6219         // directly remove entry from whitelist
6220         btstack_linked_list_iterator_remove(&it);
6221         btstack_memory_whitelist_entry_free(entry);
6222     }
6223 }
6224 
6225 /**
6226  * @brief Clear Whitelist
6227  * @returns 0 if ok
6228  */
6229 uint8_t gap_whitelist_clear(void){
6230     hci_whitelist_clear();
6231     hci_run();
6232     return ERROR_CODE_SUCCESS;
6233 }
6234 
6235 /**
6236  * @brief Add Device to Whitelist
6237  * @param address_typ
6238  * @param address
6239  * @returns 0 if ok
6240  */
6241 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6242     uint8_t status = hci_whitelist_add(address_type, address);
6243     if (status){
6244         return status;
6245     }
6246     hci_run();
6247     return ERROR_CODE_SUCCESS;
6248 }
6249 
6250 /**
6251  * @brief Remove Device from Whitelist
6252  * @param address_typ
6253  * @param address
6254  * @returns 0 if ok
6255  */
6256 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6257     uint8_t status = hci_whitelist_remove(address_type, address);
6258     if (status){
6259         return status;
6260     }
6261     hci_run();
6262     return ERROR_CODE_SUCCESS;
6263 }
6264 
6265 #ifdef ENABLE_LE_CENTRAL
6266 /**
6267  *  @brief Connect with Whitelist
6268  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6269  *  @returns - if ok
6270  */
6271 uint8_t gap_connect_with_whitelist(void){
6272     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6273         return ERROR_CODE_COMMAND_DISALLOWED;
6274     }
6275     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6276     hci_run();
6277     return ERROR_CODE_SUCCESS;
6278 }
6279 
6280 /**
6281  * @brief Auto Connection Establishment - Start Connecting to device
6282  * @param address_typ
6283  * @param address
6284  * @returns 0 if ok
6285  */
6286 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6287     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6288         return ERROR_CODE_COMMAND_DISALLOWED;
6289     }
6290 
6291     uint8_t status = hci_whitelist_add(address_type, address);
6292     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6293         return status;
6294     }
6295 
6296     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6297 
6298     hci_run();
6299     return ERROR_CODE_SUCCESS;
6300 }
6301 
6302 /**
6303  * @brief Auto Connection Establishment - Stop Connecting to device
6304  * @param address_typ
6305  * @param address
6306  * @returns 0 if ok
6307  */
6308 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6309     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6310         return ERROR_CODE_COMMAND_DISALLOWED;
6311     }
6312 
6313     hci_whitelist_remove(address_type, address);
6314     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6315         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6316     }
6317     hci_run();
6318     return 0;
6319 }
6320 
6321 /**
6322  * @brief Auto Connection Establishment - Stop everything
6323  * @note  Convenience function to stop all active auto connection attempts
6324  */
6325 uint8_t gap_auto_connection_stop_all(void){
6326     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6327         return ERROR_CODE_COMMAND_DISALLOWED;
6328     }
6329     hci_whitelist_clear();
6330     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6331     hci_run();
6332     return ERROR_CODE_SUCCESS;
6333 }
6334 
6335 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6336     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6337     if (!conn) return 0;
6338     return conn->le_connection_interval;
6339 }
6340 #endif
6341 #endif
6342 
6343 #ifdef ENABLE_CLASSIC
6344 /**
6345  * @brief Set Extended Inquiry Response data
6346  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6347  * @note has to be done before stack starts up
6348  */
6349 void gap_set_extended_inquiry_response(const uint8_t * data){
6350     hci_stack->eir_data = data;
6351     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6352     hci_run();
6353 }
6354 
6355 /**
6356  * @brief Start GAP Classic Inquiry
6357  * @param duration in 1.28s units
6358  * @return 0 if ok
6359  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6360  */
6361 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6362     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6363     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6364     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6365         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6366     }
6367     hci_stack->inquiry_state = duration_in_1280ms_units;
6368     hci_run();
6369     return 0;
6370 }
6371 
6372 /**
6373  * @brief Stop GAP Classic Inquiry
6374  * @returns 0 if ok
6375  */
6376 int gap_inquiry_stop(void){
6377     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6378         // emit inquiry complete event, before it even started
6379         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6380         hci_emit_event(event, sizeof(event), 1);
6381         return 0;
6382     }
6383     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6384     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6385     hci_run();
6386     return 0;
6387 }
6388 
6389 void gap_inquiry_set_lap(uint32_t lap){
6390     hci_stack->inquiry_lap = lap;
6391 }
6392 
6393 
6394 /**
6395  * @brief Remote Name Request
6396  * @param addr
6397  * @param page_scan_repetition_mode
6398  * @param clock_offset only used when bit 15 is set
6399  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6400  */
6401 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6402     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6403     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6404     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6405     hci_stack->remote_name_clock_offset = clock_offset;
6406     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6407     hci_run();
6408     return 0;
6409 }
6410 
6411 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6412     hci_stack->gap_pairing_state = state;
6413     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6414     hci_run();
6415     return 0;
6416 }
6417 
6418 /**
6419  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6420  * @param addr
6421  * @param pin_data
6422  * @param pin_len
6423  * @return 0 if ok
6424  */
6425 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6426     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6427     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6428     hci_stack->gap_pairing_pin_len = pin_len;
6429     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6430 }
6431 
6432 /**
6433  * @brief Legacy Pairing Pin Code Response
6434  * @param addr
6435  * @param pin
6436  * @return 0 if ok
6437  */
6438 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6439     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6440 }
6441 
6442 /**
6443  * @brief Abort Legacy Pairing
6444  * @param addr
6445  * @param pin
6446  * @return 0 if ok
6447  */
6448 int gap_pin_code_negative(bd_addr_t addr){
6449     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6450     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6451 }
6452 
6453 /**
6454  * @brief SSP Passkey Response
6455  * @param addr
6456  * @param passkey
6457  * @return 0 if ok
6458  */
6459 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6460     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6461     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6462     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6463 }
6464 
6465 /**
6466  * @brief Abort SSP Passkey Entry/Pairing
6467  * @param addr
6468  * @param pin
6469  * @return 0 if ok
6470  */
6471 int gap_ssp_passkey_negative(const bd_addr_t addr){
6472     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6473     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6474 }
6475 
6476 /**
6477  * @brief Accept SSP Numeric Comparison
6478  * @param addr
6479  * @param passkey
6480  * @return 0 if ok
6481  */
6482 int gap_ssp_confirmation_response(const bd_addr_t addr){
6483     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6484     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6485 }
6486 
6487 /**
6488  * @brief Abort SSP Numeric Comparison/Pairing
6489  * @param addr
6490  * @param pin
6491  * @return 0 if ok
6492  */
6493 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6494     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6495     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6496 }
6497 
6498 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6499 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6500     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6501     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6502     connectionSetAuthenticationFlags(conn, flag);
6503     hci_run();
6504     return ERROR_CODE_SUCCESS;
6505 }
6506 #endif
6507 
6508 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6509 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6510     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6511 }
6512 
6513 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6514     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6515 }
6516 #endif
6517 
6518 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6519 /**
6520  * @brief Report Remote OOB Data
6521  * @param bd_addr
6522  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6523  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6524  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6525  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6526  */
6527 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){
6528     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6529     if (connection == NULL) {
6530         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6531     }
6532     connection->classic_oob_c_192 = c_192;
6533     connection->classic_oob_r_192 = r_192;
6534 
6535     // ignore P-256 if not supported by us
6536     if (hci_stack->secure_connections_active){
6537         connection->classic_oob_c_256 = c_256;
6538         connection->classic_oob_r_256 = r_256;
6539     }
6540 
6541     return ERROR_CODE_SUCCESS;
6542 }
6543 /**
6544  * @brief Generate new OOB data
6545  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6546  */
6547 void gap_ssp_generate_oob_data(void){
6548     hci_stack->classic_read_local_oob_data = true;
6549     hci_run();
6550 }
6551 
6552 #endif
6553 
6554 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6555 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6556     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6557     if (connection == NULL) {
6558         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6559     }
6560 
6561     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6562     connection->link_key_type = type;
6563 
6564     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6565 }
6566 
6567 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6568 /**
6569  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6570  * @param inquiry_mode see bluetooth_defines.h
6571  */
6572 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6573     hci_stack->inquiry_mode = inquiry_mode;
6574 }
6575 
6576 /**
6577  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6578  */
6579 void hci_set_sco_voice_setting(uint16_t voice_setting){
6580     hci_stack->sco_voice_setting = voice_setting;
6581 }
6582 
6583 /**
6584  * @brief Get SCO Voice Setting
6585  * @return current voice setting
6586  */
6587 uint16_t hci_get_sco_voice_setting(void){
6588     return hci_stack->sco_voice_setting;
6589 }
6590 
6591 static int hci_have_usb_transport(void){
6592     if (!hci_stack->hci_transport) return 0;
6593     const char * transport_name = hci_stack->hci_transport->name;
6594     if (!transport_name) return 0;
6595     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6596 }
6597 
6598 /** @brief Get SCO packet length for current SCO Voice setting
6599  *  @note  Using SCO packets of the exact length is required for USB transfer
6600  *  @return Length of SCO packets in bytes (not audio frames)
6601  */
6602 uint16_t hci_get_sco_packet_length(void){
6603     uint16_t sco_packet_length = 0;
6604 
6605 #ifdef ENABLE_SCO_OVER_HCI
6606     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6607     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6608 
6609     if (hci_have_usb_transport()){
6610         // see Core Spec for H2 USB Transfer.
6611         // 3 byte SCO header + 24 bytes per connection
6612         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6613         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6614     } else {
6615         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6616         sco_packet_length = 3 + 60 * multiplier;
6617         // assert that it still fits inside an SCO buffer
6618         if (sco_packet_length > hci_stack->sco_data_packet_length){
6619             sco_packet_length = 3 + 60;
6620         }
6621     }
6622 #endif
6623 
6624 #ifdef HAVE_SCO_TRANSPORT
6625     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6626     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6627     sco_packet_length = 3 + 60 * multiplier;
6628 #endif
6629     return sco_packet_length;
6630 }
6631 
6632 /**
6633 * @brief Sets the master/slave policy
6634 * @param policy (0: attempt to become master, 1: let connecting device decide)
6635 */
6636 void hci_set_master_slave_policy(uint8_t policy){
6637     hci_stack->master_slave_policy = policy;
6638 }
6639 
6640 #endif
6641 
6642 HCI_STATE hci_get_state(void){
6643     return hci_stack->state;
6644 }
6645 
6646 #ifdef ENABLE_CLASSIC
6647 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6648     hci_stack->gap_classic_accept_callback = accept_callback;
6649 }
6650 #endif
6651 
6652 /**
6653  * @brief Set callback for Bluetooth Hardware Error
6654  */
6655 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6656     hci_stack->hardware_error_callback = fn;
6657 }
6658 
6659 void hci_disconnect_all(void){
6660     btstack_linked_list_iterator_t it;
6661     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6662     while (btstack_linked_list_iterator_has_next(&it)){
6663         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6664         if (con->state == SENT_DISCONNECT) continue;
6665         con->state = SEND_DISCONNECT;
6666     }
6667     hci_run();
6668 }
6669 
6670 uint16_t hci_get_manufacturer(void){
6671     return hci_stack->manufacturer;
6672 }
6673 
6674 #ifdef ENABLE_BLE
6675 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6676     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6677     if (!hci_con) return NULL;
6678     return &hci_con->sm_connection;
6679 }
6680 
6681 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6682 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6683 #endif
6684 
6685 int gap_encryption_key_size(hci_con_handle_t con_handle){
6686     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6687     if (hci_connection == NULL) return 0;
6688     if (hci_is_le_connection(hci_connection)){
6689 #ifdef ENABLE_BLE
6690         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6691         if (sm_conn->sm_connection_encrypted) {
6692             return sm_conn->sm_actual_encryption_key_size;
6693         }
6694 #endif
6695     } else {
6696 #ifdef ENABLE_CLASSIC
6697         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6698             return hci_connection->encryption_key_size;
6699         }
6700 #endif
6701     }
6702     return 0;
6703 }
6704 
6705 int gap_authenticated(hci_con_handle_t con_handle){
6706     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6707     if (hci_connection == NULL) return 0;
6708 
6709     switch (hci_connection->address_type){
6710 #ifdef ENABLE_BLE
6711         case BD_ADDR_TYPE_LE_PUBLIC:
6712         case BD_ADDR_TYPE_LE_RANDOM:
6713             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6714             return hci_connection->sm_connection.sm_connection_authenticated;
6715 #endif
6716 #ifdef ENABLE_CLASSIC
6717         case BD_ADDR_TYPE_SCO:
6718         case BD_ADDR_TYPE_ACL:
6719             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6720 #endif
6721         default:
6722             return 0;
6723     }
6724 }
6725 
6726 int gap_secure_connection(hci_con_handle_t con_handle){
6727     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6728     if (hci_connection == NULL) return 0;
6729 
6730     switch (hci_connection->address_type){
6731 #ifdef ENABLE_BLE
6732         case BD_ADDR_TYPE_LE_PUBLIC:
6733         case BD_ADDR_TYPE_LE_RANDOM:
6734             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6735             return hci_connection->sm_connection.sm_connection_sc;
6736 #endif
6737 #ifdef ENABLE_CLASSIC
6738         case BD_ADDR_TYPE_SCO:
6739         case BD_ADDR_TYPE_ACL:
6740             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6741 #endif
6742         default:
6743             return 0;
6744     }
6745 }
6746 
6747 bool gap_bonded(hci_con_handle_t con_handle){
6748 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6749 	if (hci_connection == NULL) return 0;
6750 
6751 #ifdef ENABLE_CLASSIC
6752 	link_key_t link_key;
6753 	link_key_type_t link_key_type;
6754 #endif
6755 	switch (hci_connection->address_type){
6756 #ifdef ENABLE_BLE
6757 		case BD_ADDR_TYPE_LE_PUBLIC:
6758 		case BD_ADDR_TYPE_LE_RANDOM:
6759 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6760 #endif
6761 #ifdef ENABLE_CLASSIC
6762 		case BD_ADDR_TYPE_SCO:
6763 		case BD_ADDR_TYPE_ACL:
6764 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6765 #endif
6766 		default:
6767 			return false;
6768 	}
6769 }
6770 
6771 #ifdef ENABLE_BLE
6772 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6773     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6774     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6775     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6776     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6777     return sm_conn->sm_connection_authorization_state;
6778 }
6779 #endif
6780 
6781 #ifdef ENABLE_CLASSIC
6782 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){
6783     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6784     if (!conn) return GAP_CONNECTION_INVALID;
6785     conn->sniff_min_interval = sniff_min_interval;
6786     conn->sniff_max_interval = sniff_max_interval;
6787     conn->sniff_attempt = sniff_attempt;
6788     conn->sniff_timeout = sniff_timeout;
6789     hci_run();
6790     return 0;
6791 }
6792 
6793 /**
6794  * @brief Exit Sniff mode
6795  * @param con_handle
6796  @ @return 0 if ok
6797  */
6798 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6799     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6800     if (!conn) return GAP_CONNECTION_INVALID;
6801     conn->sniff_min_interval = 0xffff;
6802     hci_run();
6803     return 0;
6804 }
6805 
6806 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){
6807     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6808     if (!conn) return GAP_CONNECTION_INVALID;
6809     conn->sniff_subrating_max_latency = max_latency;
6810     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6811     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6812     hci_run();
6813     return ERROR_CODE_SUCCESS;
6814 }
6815 
6816 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){
6817     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6818     if (!conn) return GAP_CONNECTION_INVALID;
6819     conn->qos_service_type = service_type;
6820     conn->qos_token_rate = token_rate;
6821     conn->qos_peak_bandwidth = peak_bandwidth;
6822     conn->qos_latency = latency;
6823     conn->qos_delay_variation = delay_variation;
6824     hci_run();
6825     return ERROR_CODE_SUCCESS;
6826 }
6827 
6828 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6829     hci_stack->new_page_scan_interval = page_scan_interval;
6830     hci_stack->new_page_scan_window = page_scan_window;
6831     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6832     hci_run();
6833 }
6834 
6835 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6836     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6837     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6838     hci_run();
6839 }
6840 
6841 #endif
6842 
6843 void hci_halting_defer(void){
6844     if (hci_stack->state != HCI_STATE_HALTING) return;
6845     switch (hci_stack->substate){
6846         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6847         case HCI_HALTING_CLOSE:
6848             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6849             break;
6850         default:
6851             break;
6852     }
6853 }
6854 
6855 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6856 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6857     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6858     if (le_device_db_index >= le_device_db_max_count()) return;
6859     uint8_t offset = le_device_db_index >> 3;
6860     uint8_t mask = 1 << (le_device_db_index & 7);
6861     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6862     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6863     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6864         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6865     }
6866 }
6867 
6868 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6869 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6870 	if (le_device_db_index >= le_device_db_max_count()) return;
6871 	uint8_t offset = le_device_db_index >> 3;
6872 	uint8_t mask = 1 << (le_device_db_index & 7);
6873 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6874 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6875 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6876 	}
6877 }
6878 
6879 uint8_t gap_load_resolving_list_from_le_device_db(void){
6880 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6881 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6882 	}
6883 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6884 		// restart le resolving list update
6885 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6886 	}
6887 	return ERROR_CODE_SUCCESS;
6888 }
6889 #endif
6890 
6891 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6892 void hci_setup_test_connections_fuzz(void){
6893     hci_connection_t * conn;
6894 
6895     // default address: 66:55:44:33:00:01
6896     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6897 
6898     // setup Controller info
6899     hci_stack->num_cmd_packets = 255;
6900     hci_stack->acl_packets_total_num = 255;
6901 
6902     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6903     addr[5] = 0x01;
6904     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6905     conn->con_handle = addr[5];
6906     conn->role  = HCI_ROLE_SLAVE;
6907     conn->state = RECEIVED_CONNECTION_REQUEST;
6908     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6909 
6910     // setup incoming Classic SCO connection with con handle 0x0002
6911     addr[5] = 0x02;
6912     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6913     conn->con_handle = addr[5];
6914     conn->role  = HCI_ROLE_SLAVE;
6915     conn->state = RECEIVED_CONNECTION_REQUEST;
6916     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6917 
6918     // setup ready Classic ACL connection with con handle 0x0003
6919     addr[5] = 0x03;
6920     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6921     conn->con_handle = addr[5];
6922     conn->role  = HCI_ROLE_SLAVE;
6923     conn->state = OPEN;
6924     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6925 
6926     // setup ready Classic SCO connection with con handle 0x0004
6927     addr[5] = 0x04;
6928     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6929     conn->con_handle = addr[5];
6930     conn->role  = HCI_ROLE_SLAVE;
6931     conn->state = OPEN;
6932     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6933 
6934     // setup ready LE ACL connection with con handle 0x005 and public address
6935     addr[5] = 0x05;
6936     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6937     conn->con_handle = addr[5];
6938     conn->role  = HCI_ROLE_SLAVE;
6939     conn->state = OPEN;
6940     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6941     conn->sm_connection.sm_connection_encrypted = 1;
6942 }
6943 
6944 void hci_free_connections_fuzz(void){
6945     btstack_linked_list_iterator_t it;
6946     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6947     while (btstack_linked_list_iterator_has_next(&it)){
6948         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6949         btstack_linked_list_iterator_remove(&it);
6950         btstack_memory_hci_connection_free(con);
6951     }
6952 }
6953 void hci_simulate_working_fuzz(void){
6954     hci_init_done();
6955     hci_stack->num_cmd_packets = 255;
6956 }
6957 #endif
6958