xref: /btstack/src/hci.c (revision 5ffe9d0bfe40fc60b3546856dab4123c6124ab34)
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             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1626             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1627             break;
1628         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1629             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1630             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1631             break;
1632         case HCI_INIT_WRITE_INQUIRY_MODE:
1633             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1634             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1635             break;
1636         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1637             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1638 			hci_stack->secure_connections_active = true;
1639             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1640             break;
1641         // only sent if ENABLE_SCO_OVER_HCI is defined
1642         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1643             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1644             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1645             break;
1646         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1647             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1648             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1649             break;
1650         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1651         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1652             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1653 #ifdef ENABLE_SCO_OVER_HCI
1654             log_info("BCM: Route SCO data via HCI transport");
1655             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1656 #endif
1657 #ifdef ENABLE_SCO_OVER_PCM
1658             log_info("BCM: Route SCO data via PCM interface");
1659 #ifdef ENABLE_BCM_PCM_WBS
1660             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1661             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1662 #else
1663             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1664             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1665 #endif
1666 #endif
1667             break;
1668 #ifdef ENABLE_SCO_OVER_PCM
1669         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1670             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1671             log_info("BCM: Config PCM interface for I2S");
1672 #ifdef ENABLE_BCM_PCM_WBS
1673             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1674             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1675 #else
1676             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1677             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1678 #endif
1679             break;
1680 #endif
1681 #endif
1682 
1683 #ifdef ENABLE_BLE
1684         // LE INIT
1685         case HCI_INIT_LE_READ_BUFFER_SIZE:
1686             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1687             hci_send_cmd(&hci_le_read_buffer_size);
1688             break;
1689         case HCI_INIT_LE_SET_EVENT_MASK:
1690             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1691             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1692             break;
1693         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1694             // LE Supported Host = 1, Simultaneous Host = 0
1695             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1696             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1697             break;
1698 #endif
1699 
1700 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1701         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1702             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1703             hci_send_cmd(&hci_le_read_maximum_data_length);
1704             break;
1705         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1706             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1707             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1708             break;
1709 #endif
1710 
1711 #ifdef ENABLE_LE_CENTRAL
1712         case HCI_INIT_READ_WHITE_LIST_SIZE:
1713             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1714             hci_send_cmd(&hci_le_read_white_list_size);
1715             break;
1716         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1717             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1718             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);
1719             break;
1720 #endif
1721         default:
1722             return;
1723     }
1724 }
1725 
1726 static void hci_init_done(void){
1727 #ifdef ENABLE_CLASSIC
1728     // init sequence complete, check if GAP Tasks are completed
1729     if (hci_stack->gap_tasks != 0) {
1730         hci_run_gap_tasks_classic();
1731         return;
1732     }
1733 #endif
1734 
1735     // done. tell the app
1736     log_info("hci_init_done -> HCI_STATE_WORKING");
1737     hci_stack->state = HCI_STATE_WORKING;
1738     hci_emit_state();
1739     hci_run();
1740 }
1741 
1742 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1743     bool command_completed = false;
1744     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1745         uint16_t opcode = little_endian_read_16(packet,3);
1746         if (opcode == hci_stack->last_cmd_opcode){
1747             command_completed = true;
1748             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1749         } else {
1750             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1751         }
1752     }
1753 
1754     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1755         uint8_t  status = packet[2];
1756         uint16_t opcode = little_endian_read_16(packet,4);
1757         if (opcode == hci_stack->last_cmd_opcode){
1758             if (status){
1759                 command_completed = true;
1760                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1761             } else {
1762                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1763             }
1764         } else {
1765             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1766         }
1767     }
1768 #ifndef HAVE_HOST_CONTROLLER_API
1769     // Vendor == CSR
1770     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1771         // TODO: track actual command
1772         command_completed = true;
1773     }
1774 
1775     // Vendor == Toshiba
1776     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1777         // TODO: track actual command
1778         command_completed = true;
1779         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1780         hci_stack->num_cmd_packets = 1;
1781     }
1782 #endif
1783 
1784     return command_completed;
1785 }
1786 
1787 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1788 
1789     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1790 
1791     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1792 
1793 #ifndef HAVE_HOST_CONTROLLER_API
1794 
1795     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1796     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1797     //
1798     // HCI Reset
1799     // Timeout 100 ms
1800     // HCI Reset
1801     // Command Complete Reset
1802     // HCI Read Local Version Information
1803     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1804     // hang...
1805     //
1806     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1807     if (!command_completed
1808             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1809             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1810 
1811         uint16_t opcode = little_endian_read_16(packet,3);
1812         if (opcode == hci_reset.opcode){
1813             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1814             return;
1815         }
1816     }
1817 
1818     // CSR & H5
1819     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1820     if (!command_completed
1821             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1822             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1823 
1824         uint16_t opcode = little_endian_read_16(packet,3);
1825         if (opcode == hci_reset.opcode){
1826             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1827             return;
1828         }
1829     }
1830 
1831     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1832     // fix: Correct substate and behave as command below
1833     if (command_completed){
1834         switch (hci_stack->substate){
1835             case HCI_INIT_SEND_RESET:
1836                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1837                 break;
1838             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1839                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1840                 break;
1841             default:
1842                 break;
1843         }
1844     }
1845 
1846 #endif
1847 
1848     if (!command_completed) return;
1849 
1850     bool need_baud_change = false;
1851     bool need_addr_change = false;
1852 
1853 #ifndef HAVE_HOST_CONTROLLER_API
1854     need_baud_change = hci_stack->config
1855                         && hci_stack->chipset
1856                         && hci_stack->chipset->set_baudrate_command
1857                         && hci_stack->hci_transport->set_baudrate
1858                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1859 
1860     need_addr_change = hci_stack->custom_bd_addr_set
1861                         && hci_stack->chipset
1862                         && hci_stack->chipset->set_bd_addr_command;
1863 #endif
1864 
1865     switch(hci_stack->substate){
1866 
1867 #ifndef HAVE_HOST_CONTROLLER_API
1868         case HCI_INIT_SEND_RESET:
1869             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1870             // fix: just correct substate and behave as command below
1871 
1872             /* fall through */
1873 #endif
1874 
1875         case HCI_INIT_W4_SEND_RESET:
1876             btstack_run_loop_remove_timer(&hci_stack->timeout);
1877             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1878             return;
1879 
1880 #ifndef HAVE_HOST_CONTROLLER_API
1881         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1882             // for STLC2500D, baud rate change already happened.
1883             // for others, baud rate gets changed now
1884             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1885                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1886                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1887                 hci_stack->hci_transport->set_baudrate(baud_rate);
1888             }
1889             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1890             return;
1891         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1892             btstack_run_loop_remove_timer(&hci_stack->timeout);
1893             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1894             return;
1895         case HCI_INIT_W4_CUSTOM_INIT:
1896             // repeat custom init
1897             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1898             return;
1899 #endif
1900 
1901         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1902             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1903               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1904                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1905                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1906                 return;
1907             }
1908             if (need_addr_change){
1909                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1910                 return;
1911             }
1912             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1913             return;
1914 #ifndef HAVE_HOST_CONTROLLER_API
1915         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1916             if (need_baud_change){
1917                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1918                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1919                 hci_stack->hci_transport->set_baudrate(baud_rate);
1920             }
1921             if (need_addr_change){
1922                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1923                 return;
1924             }
1925             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1926             return;
1927         case HCI_INIT_W4_SET_BD_ADDR:
1928             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1929             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1930             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1931                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1932                 return;
1933             }
1934             // skipping st warm boot
1935             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1936             return;
1937         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1938             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1939             return;
1940 #endif
1941         case HCI_INIT_W4_SET_EVENT_MASK:
1942             // skip Classic init commands for LE only chipsets
1943             if (!hci_classic_supported()){
1944 #ifdef ENABLE_BLE
1945                 if (hci_le_supported()){
1946                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1947                     return;
1948                 }
1949 #endif
1950                 log_error("Neither BR/EDR nor LE supported");
1951                 hci_init_done();
1952                 return;
1953             }
1954             if (!gap_ssp_supported()){
1955                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1956                 return;
1957             }
1958             break;
1959 #ifdef ENABLE_BLE
1960         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1961             // skip write le host if not supported (e.g. on LE only EM9301)
1962             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1963             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1964             return;
1965 
1966 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1967         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1968             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1969             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1970                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1971                 return;
1972             }
1973             // explicit fall through to reduce repetitions
1974 
1975 #ifdef ENABLE_LE_CENTRAL
1976             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1977 #else
1978             hci_init_done();
1979 #endif
1980             return;
1981 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1982 
1983 #endif  /* ENABLE_BLE */
1984 
1985         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1986             // skip write secure connections host support if not supported or disabled
1987             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1988                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1989                 return;
1990             }
1991             break;
1992 
1993 #ifdef ENABLE_SCO_OVER_HCI
1994         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1995             // skip write synchronous flow control if not supported
1996             if (hci_stack->local_supported_commands[0] & 0x04) break;
1997             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1998 
1999             /* fall through */
2000 
2001         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2002             // skip write default erroneous data reporting if not supported
2003             if (hci_stack->local_supported_commands[0] & 0x08) break;
2004             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
2005 
2006             /* fall through */
2007 
2008         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
2009             // skip bcm set sco pcm config on non-Broadcom chipsets
2010             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
2011             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2012 
2013             /* fall through */
2014 
2015         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
2016             if (!hci_le_supported()){
2017                 // SKIP LE init for Classic only configuration
2018                 hci_init_done();
2019                 return;
2020             }
2021             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2022             break;
2023 
2024 #else /* !ENABLE_SCO_OVER_HCI */
2025 
2026         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2027 #ifdef ENABLE_SCO_OVER_PCM
2028             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
2029                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
2030                 return;
2031             }
2032 #endif
2033             /* fall through */
2034 
2035         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
2036 #ifdef ENABLE_BLE
2037             if (hci_le_supported()){
2038                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
2039                 return;
2040             }
2041 #endif
2042             // SKIP LE init for Classic only configuration
2043             hci_init_done();
2044             return;
2045 #endif /* ENABLE_SCO_OVER_HCI */
2046 
2047 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2048 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2049         // Response to command before init done state -> init done
2050         case (HCI_INIT_DONE-1):
2051             hci_init_done();
2052             return;
2053 #endif
2054 
2055         default:
2056             break;
2057     }
2058     hci_initializing_next_state();
2059 }
2060 
2061 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2062     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2063     bd_addr_t bd_address;
2064     (void)memcpy(&bd_address, conn->address, 6);
2065 
2066 #ifdef ENABLE_CLASSIC
2067     // cache needed data
2068     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2069 #endif
2070 
2071     // connection failed, remove entry
2072     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2073     btstack_memory_hci_connection_free( conn );
2074 
2075 #ifdef ENABLE_CLASSIC
2076     // notify client if dedicated bonding
2077     if (notify_dedicated_bonding_failed){
2078         log_info("hci notify_dedicated_bonding_failed");
2079         hci_emit_dedicated_bonding_result(bd_address, status);
2080     }
2081 
2082     // if authentication error, also delete link key
2083     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2084         gap_drop_link_key_for_bd_addr(bd_address);
2085     }
2086 #else
2087     UNUSED(status);
2088 #endif
2089 }
2090 
2091 #ifdef ENABLE_CLASSIC
2092 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2093     // SSP Controller
2094     if (features[6] & (1 << 3)){
2095         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2096     }
2097     // eSCO
2098     if (features[3] & (1<<7)){
2099         conn->remote_supported_features[0] |= 1;
2100     }
2101     // Extended features
2102     if (features[7] & (1<<7)){
2103         conn->remote_supported_features[0] |= 2;
2104     }
2105 }
2106 
2107 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2108     // SSP Host
2109     if (features[0] & (1 << 0)){
2110         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2111     }
2112     // SC Host
2113     if (features[0] & (1 << 3)){
2114         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2115     }
2116 }
2117 
2118 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2119     // SC Controller
2120     if (features[1] & (1 << 0)){
2121         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2122     }
2123 }
2124 
2125 static void hci_handle_remote_features_received(hci_connection_t * conn){
2126     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2127     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2128     if (conn->bonding_flags & BONDING_DEDICATED){
2129         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2130     }
2131 }
2132 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2133     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2134     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2135 }
2136 
2137 #endif
2138 
2139 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2140     // handle BT initialization
2141     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2142         hci_initializing_event_handler(packet, size);
2143     }
2144 
2145     // help with BT sleep
2146     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2147         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2148         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2149         hci_initializing_next_state();
2150     }
2151 }
2152 
2153 #ifdef ENABLE_CLASSIC
2154 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2155     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2156     conn->encryption_key_size = encryption_key_size;
2157 
2158     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2159         conn->requested_security_level = LEVEL_0;
2160         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2161         return;
2162     }
2163 
2164     // Request Authentication if not already done
2165     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2166     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2167 }
2168 #endif
2169 
2170 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2171     UNUSED(size);
2172 
2173     uint16_t manufacturer;
2174 #ifdef ENABLE_CLASSIC
2175     hci_con_handle_t handle;
2176     hci_connection_t * conn;
2177     uint8_t status;
2178 #endif
2179     // get num cmd packets - limit to 1 to reduce complexity
2180     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2181 
2182     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2183     switch (opcode){
2184         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2185             if (packet[5]) break;
2186             // terminate, name 248 chars
2187             packet[6+248] = 0;
2188             log_info("local name: %s", &packet[6]);
2189             break;
2190         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2191             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2192             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2193                 uint16_t acl_len = little_endian_read_16(packet, 6);
2194                 uint16_t sco_len = packet[8];
2195 
2196                 // determine usable ACL/SCO payload size
2197                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2198                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2199 
2200                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2201                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2202 
2203                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2204                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2205                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2206             }
2207             break;
2208         case HCI_OPCODE_HCI_READ_RSSI:
2209             if (packet[5] == ERROR_CODE_SUCCESS){
2210                 uint8_t event[5];
2211                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2212                 event[1] = 3;
2213                 (void)memcpy(&event[2], &packet[6], 3);
2214                 hci_emit_event(event, sizeof(event), 1);
2215             }
2216             break;
2217 #ifdef ENABLE_BLE
2218         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2219             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2220             hci_stack->le_acl_packets_total_num = packet[8];
2221             // determine usable ACL payload size
2222             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2223                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2224             }
2225             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2226             break;
2227 #endif
2228 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2229         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2230             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2231             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2232             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);
2233             break;
2234 #endif
2235 #ifdef ENABLE_LE_CENTRAL
2236         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2237             hci_stack->le_whitelist_capacity = packet[6];
2238             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2239             break;
2240 #endif
2241         case HCI_OPCODE_HCI_READ_BD_ADDR:
2242             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2243             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));
2244 #ifdef ENABLE_CLASSIC
2245             if (hci_stack->link_key_db){
2246                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2247             }
2248 #endif
2249             break;
2250 #ifdef ENABLE_CLASSIC
2251         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2252             hci_emit_discoverable_enabled(hci_stack->discoverable);
2253             break;
2254         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2255             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2256                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2257                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2258                 hci_emit_event(event, sizeof(event), 1);
2259             }
2260             break;
2261 #endif
2262         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2263             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2264 
2265 #ifdef ENABLE_CLASSIC
2266             // determine usable ACL packet types based on host buffer size and supported features
2267             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2268             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2269 #endif
2270             // Classic/LE
2271             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2272             break;
2273         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2274             manufacturer = little_endian_read_16(packet, 10);
2275             // map Cypress to Broadcom
2276             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2277                 log_info("Treat Cypress as Broadcom");
2278                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2279                 little_endian_store_16(packet, 10, manufacturer);
2280             }
2281             hci_stack->manufacturer = manufacturer;
2282             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2283             break;
2284         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2285             hci_stack->local_supported_commands[0] =
2286                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2287                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2288                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2289                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2290                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2291                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2292                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2293                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2294             hci_stack->local_supported_commands[1] =
2295                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2296                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2297                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2298                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2299                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2300             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2301             break;
2302 #ifdef ENABLE_CLASSIC
2303         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2304             if (packet[5]) return;
2305             hci_stack->synchronous_flow_control_enabled = 1;
2306             break;
2307         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2308             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2309             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2310             conn   = hci_connection_for_handle(handle);
2311             if (conn != NULL) {
2312                 uint8_t key_size = 0;
2313                 if (status == 0){
2314                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2315                     log_info("Handle %04x key Size: %u", handle, key_size);
2316                 } else {
2317                     key_size = 1;
2318                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2319                 }
2320                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2321             }
2322             break;
2323         // assert pairing complete event is emitted.
2324         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2325         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2326         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2327         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2328             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2329             // lookup connection by gap pairing addr
2330             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2331             if (conn == NULL) break;
2332             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2333             break;
2334 
2335 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2336         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2337         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2338             uint8_t event[67];
2339             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2340             event[1] = 65;
2341             (void)memset(&event[2], 0, 65);
2342             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2343                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2344                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2345                     event[2] = 3;
2346                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2347                 } else {
2348                     event[2] = 1;
2349                 }
2350             }
2351             hci_emit_event(event, sizeof(event), 0);
2352             break;
2353         }
2354 
2355         // note: only needed if user does not provide OOB data
2356         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2357             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2358             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2359             if (conn == NULL) break;
2360             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2361             break;
2362 #endif
2363 #endif
2364         default:
2365             break;
2366     }
2367 }
2368 
2369 #ifdef ENABLE_BLE
2370 static void event_handle_le_connection_complete(const uint8_t * packet){
2371 	bd_addr_t addr;
2372 	bd_addr_type_t addr_type;
2373 	hci_connection_t * conn;
2374 
2375 	// Connection management
2376 	reverse_bd_addr(&packet[8], addr);
2377 	addr_type = (bd_addr_type_t)packet[7];
2378 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2379 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2380 
2381 #ifdef ENABLE_LE_CENTRAL
2382 	// handle error: error is reported only to the initiator -> outgoing connection
2383 	if (packet[3]){
2384 
2385 		// handle cancelled outgoing connection
2386 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2387 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2388 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2389 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2390 		    // reset state
2391             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2392             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2393 			// get outgoing connection conn struct for direct connect
2394 			conn = gap_get_outgoing_connection();
2395 		}
2396 
2397 		// outgoing le connection establishment is done
2398 		if (conn){
2399 			// remove entry
2400 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2401 			btstack_memory_hci_connection_free( conn );
2402 		}
2403 		return;
2404 	}
2405 #endif
2406 
2407 	// on success, both hosts receive connection complete event
2408 	if (packet[6] == HCI_ROLE_MASTER){
2409 #ifdef ENABLE_LE_CENTRAL
2410 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2411 		// note: no hci_connection_t object exists yet for connect with whitelist
2412 		if (hci_is_le_connection_type(addr_type)){
2413 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2414 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2415 		}
2416 #endif
2417 	} else {
2418 #ifdef ENABLE_LE_PERIPHERAL
2419 		// if we're slave, it was an incoming connection, advertisements have stopped
2420 		hci_stack->le_advertisements_active = false;
2421 #endif
2422 	}
2423 
2424 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2425 	if (!conn){
2426 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2427 	}
2428 
2429 	// no memory, sorry.
2430 	if (!conn){
2431 		return;
2432 	}
2433 
2434 	conn->state = OPEN;
2435 	conn->role  = packet[6];
2436 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2437 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2438 
2439 #ifdef ENABLE_LE_PERIPHERAL
2440 	if (packet[6] == HCI_ROLE_SLAVE){
2441 		hci_update_advertisements_enabled_for_current_roles();
2442 	}
2443 #endif
2444 
2445     // init unenhanced att bearer mtu
2446     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2447     conn->att_connection.mtu_exchanged = false;
2448 
2449     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2450 
2451 	// restart timer
2452 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2453 	// btstack_run_loop_add_timer(&conn->timeout);
2454 
2455 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2456 
2457 	hci_emit_nr_connections_changed();
2458 }
2459 #endif
2460 
2461 #ifdef ENABLE_CLASSIC
2462 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){
2463     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2464     // LEVEL_4 is tested by l2cap
2465     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2466     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2467     if (level >= LEVEL_3){
2468         // MITM not possible without keyboard or display
2469         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2470         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2471 
2472         // MITM possible if one side has keyboard and the other has keyboard or display
2473         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2474         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2475 
2476         // MITM not possible if one side has only display and other side has no keyboard
2477         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2478         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2479     }
2480     // LEVEL 2 requires SSP, which is a given
2481     return true;
2482 }
2483 
2484 static bool btstack_is_null(uint8_t * data, uint16_t size){
2485     uint16_t i;
2486     for (i=0; i < size ; i++){
2487         if (data[i] != 0) {
2488             return false;
2489         }
2490     }
2491     return true;
2492 }
2493 
2494 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2495     // get requested security level
2496     gap_security_level_t requested_security_level = conn->requested_security_level;
2497     if (hci_stack->gap_secure_connections_only_mode){
2498         requested_security_level = LEVEL_4;
2499     }
2500 
2501     // assess security: LEVEL 4 requires SC
2502     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2503     if ((requested_security_level == LEVEL_4) &&
2504         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2505         !hci_remote_sc_enabled(conn)){
2506         log_info("Level 4 required, but SC not supported -> abort");
2507         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2508         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2509         return;
2510     }
2511 
2512     // assess security based on io capabilities
2513     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2514         // responder: fully validate io caps of both sides as well as OOB data
2515         bool security_possible = false;
2516         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2517 
2518 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2519         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2520         // so we merge the OOB data availability
2521         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2522         if (conn->classic_oob_c_192 != NULL){
2523             have_oob_data |= 1;
2524         }
2525         if (conn->classic_oob_c_256 != NULL){
2526             have_oob_data |= 2;
2527         }
2528         // for up to Level 3, either P-192 as well as P-256 will do
2529         // 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
2530         // if remote does not SC, we should not receive P-256 data either
2531         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2532             security_possible = true;
2533         }
2534         // for Level 4, P-256 is needed
2535         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2536             security_possible = true;
2537         }
2538 #endif
2539 
2540         if (security_possible == false){
2541             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2542             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2543             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2544             return;
2545         }
2546     } else {
2547         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2548 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2549 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2550         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2551             log_info("Level 3+ required, but no input/output -> abort");
2552             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2553             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2554             return;
2555         }
2556 #endif
2557 #endif
2558     }
2559 
2560 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2561     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2562         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2563     } else {
2564         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2565     }
2566 #endif
2567 }
2568 
2569 #endif
2570 
2571 static void event_handler(uint8_t *packet, uint16_t size){
2572 
2573     uint16_t event_length = packet[1];
2574 
2575     // assert packet is complete
2576     if (size != (event_length + 2u)){
2577         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2578         return;
2579     }
2580 
2581     bd_addr_type_t addr_type;
2582     hci_con_handle_t handle;
2583     hci_connection_t * conn;
2584     int i;
2585     int create_connection_cmd;
2586 
2587 #ifdef ENABLE_CLASSIC
2588     hci_link_type_t link_type;
2589     bd_addr_t addr;
2590 #endif
2591 
2592     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2593 
2594     switch (hci_event_packet_get_type(packet)) {
2595 
2596         case HCI_EVENT_COMMAND_COMPLETE:
2597             handle_command_complete_event(packet, size);
2598             break;
2599 
2600         case HCI_EVENT_COMMAND_STATUS:
2601             // get num cmd packets - limit to 1 to reduce complexity
2602             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2603 
2604             // check command status to detected failed outgoing connections
2605             create_connection_cmd = 0;
2606 #ifdef ENABLE_CLASSIC
2607             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2608                 create_connection_cmd = 1;
2609             }
2610 #endif
2611 #ifdef ENABLE_LE_CENTRAL
2612             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2613                 create_connection_cmd = 1;
2614             }
2615 #endif
2616             if (create_connection_cmd) {
2617                 uint8_t status = hci_event_command_status_get_status(packet);
2618                 addr_type = hci_stack->outgoing_addr_type;
2619                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2620                 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);
2621 
2622                 // reset outgoing address info
2623                 memset(hci_stack->outgoing_addr, 0, 6);
2624                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2625 
2626                 // on error
2627                 if (status != ERROR_CODE_SUCCESS){
2628 #ifdef ENABLE_LE_CENTRAL
2629                     if (hci_is_le_connection_type(addr_type)){
2630                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2631                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2632                     }
2633 #endif
2634                     // error => outgoing connection failed
2635                     if (conn != NULL){
2636                         hci_handle_connection_failed(conn, status);
2637                     }
2638                 }
2639             }
2640 
2641 #ifdef ENABLE_CLASSIC
2642             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2643                 uint8_t status = hci_event_command_status_get_status(packet);
2644                 log_info("command status (inquiry), status %x", status);
2645                 if (status == ERROR_CODE_SUCCESS) {
2646                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2647                 } else {
2648                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2649                 }
2650             }
2651 #endif
2652             break;
2653 
2654         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2655             if (size < 3) return;
2656             uint16_t num_handles = packet[2];
2657             if (size != (3u + num_handles * 4u)) return;
2658             uint16_t offset = 3;
2659             for (i=0; i<num_handles;i++){
2660                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2661                 offset += 2u;
2662                 uint16_t num_packets = little_endian_read_16(packet, offset);
2663                 offset += 2u;
2664 
2665                 conn = hci_connection_for_handle(handle);
2666                 if (!conn){
2667                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2668                     continue;
2669                 }
2670 
2671                 if (conn->num_packets_sent >= num_packets){
2672                     conn->num_packets_sent -= num_packets;
2673                 } else {
2674                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2675                     conn->num_packets_sent = 0;
2676                 }
2677                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2678 
2679 #ifdef ENABLE_CLASSIC
2680                 // For SCO, we do the can_send_now_check here
2681                 hci_notify_if_sco_can_send_now();
2682 #endif
2683             }
2684             break;
2685         }
2686 
2687 #ifdef ENABLE_CLASSIC
2688         case HCI_EVENT_INQUIRY_COMPLETE:
2689             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2690                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2691                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2692                 hci_emit_event(event, sizeof(event), 1);
2693             }
2694             break;
2695         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2696             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2697                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2698             }
2699             break;
2700         case HCI_EVENT_CONNECTION_REQUEST:
2701             reverse_bd_addr(&packet[2], addr);
2702             link_type = (hci_link_type_t) packet[11];
2703 
2704             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2705             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2706                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2707                 bd_addr_copy(hci_stack->decline_addr, addr);
2708                 break;
2709             }
2710 
2711             if (hci_stack->gap_classic_accept_callback != NULL){
2712                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2713                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2714                     bd_addr_copy(hci_stack->decline_addr, addr);
2715                     break;
2716                 }
2717             }
2718 
2719             // TODO: eval COD 8-10
2720             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2721             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2722             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2723             if (!conn) {
2724                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2725             }
2726             if (!conn) {
2727                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2728                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2729                 bd_addr_copy(hci_stack->decline_addr, addr);
2730                 break;
2731             }
2732             conn->role  = HCI_ROLE_SLAVE;
2733             conn->state = RECEIVED_CONNECTION_REQUEST;
2734             // store info about eSCO
2735             if (link_type == HCI_LINK_TYPE_ESCO){
2736                 conn->remote_supported_features[0] |= 1;
2737             }
2738             hci_run();
2739             break;
2740 
2741         case HCI_EVENT_CONNECTION_COMPLETE:
2742             // Connection management
2743             reverse_bd_addr(&packet[5], addr);
2744             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2745             addr_type = BD_ADDR_TYPE_ACL;
2746             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2747             if (conn) {
2748                 if (!packet[2]){
2749                     conn->state = OPEN;
2750                     conn->con_handle = little_endian_read_16(packet, 3);
2751 
2752                     // queue get remote feature
2753                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2754 
2755                     // queue set supervision timeout if we're master
2756                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2757                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2758                     }
2759 
2760                     // restart timer
2761                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2762                     btstack_run_loop_add_timer(&conn->timeout);
2763 
2764                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2765 
2766                     hci_emit_nr_connections_changed();
2767                 } else {
2768                     // connection failed
2769                     hci_handle_connection_failed(conn, packet[2]);
2770                 }
2771             }
2772             break;
2773 
2774         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2775             reverse_bd_addr(&packet[5], addr);
2776             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2777             if (packet[2]){
2778                 // connection failed
2779                 break;
2780             }
2781             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2782             if (!conn) {
2783                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2784             }
2785             if (!conn) {
2786                 break;
2787             }
2788             conn->state = OPEN;
2789             conn->con_handle = little_endian_read_16(packet, 3);
2790 
2791 #ifdef ENABLE_SCO_OVER_HCI
2792             // update SCO
2793             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2794                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2795             }
2796             // trigger can send now
2797             if (hci_have_usb_transport()){
2798                 hci_stack->sco_can_send_now = true;
2799             }
2800 #endif
2801 #ifdef HAVE_SCO_TRANSPORT
2802             // configure sco transport
2803             if (hci_stack->sco_transport != NULL){
2804                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2805                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2806             }
2807 #endif
2808             break;
2809 
2810         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2811             handle = little_endian_read_16(packet, 3);
2812             conn = hci_connection_for_handle(handle);
2813             if (!conn) break;
2814             if (!packet[2]){
2815                 const uint8_t * features = &packet[5];
2816                 hci_handle_remote_features_page_0(conn, features);
2817 
2818                 // read extended features if possible
2819                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2820                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2821                     break;
2822                 }
2823             }
2824             hci_handle_remote_features_received(conn);
2825             break;
2826 
2827         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2828             handle = little_endian_read_16(packet, 3);
2829             conn = hci_connection_for_handle(handle);
2830             if (!conn) break;
2831             // status = ok, page = 1
2832             if (!packet[2]) {
2833                 uint8_t page_number = packet[5];
2834                 uint8_t maximum_page_number = packet[6];
2835                 const uint8_t * features = &packet[7];
2836                 bool done = false;
2837                 switch (page_number){
2838                     case 1:
2839                         hci_handle_remote_features_page_1(conn, features);
2840                         if (maximum_page_number >= 2){
2841                             // get Secure Connections (Controller) from Page 2 if available
2842                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2843                         } else {
2844                             // otherwise, assume SC (Controller) == SC (Host)
2845                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2846                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2847                             }
2848                             done = true;
2849                         }
2850                         break;
2851                     case 2:
2852                         hci_handle_remote_features_page_2(conn, features);
2853                         done = true;
2854                         break;
2855                     default:
2856                         break;
2857                 }
2858                 if (!done) break;
2859             }
2860             hci_handle_remote_features_received(conn);
2861             break;
2862 
2863         case HCI_EVENT_LINK_KEY_REQUEST:
2864 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2865             hci_event_link_key_request_get_bd_addr(packet, addr);
2866             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2867             if (!conn) break;
2868 
2869             // lookup link key in db if not cached
2870             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2871                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2872             }
2873 
2874             // response sent by hci_run()
2875             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2876 #endif
2877             break;
2878 
2879         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2880             hci_event_link_key_request_get_bd_addr(packet, addr);
2881             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2882             if (!conn) break;
2883 
2884             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2885 
2886             // CVE-2020-26555: ignore NULL link key
2887             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2888             if (btstack_is_null(&packet[8], 16)) break;
2889 
2890             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2891             // Change Connection Encryption keeps link key type
2892             if (link_key_type != CHANGED_COMBINATION_KEY){
2893                 conn->link_key_type = link_key_type;
2894             }
2895 
2896             // cache link key. link keys stored in little-endian format for legacy reasons
2897             memcpy(&conn->link_key, &packet[8], 16);
2898 
2899             // only store link key:
2900             // - if bondable enabled
2901             if (hci_stack->bondable == false) break;
2902             // - if security level sufficient
2903             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2904             // - for SSP, also check if remote side requested bonding as well
2905             if (conn->link_key_type != COMBINATION_KEY){
2906                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2907                 if (!remote_bonding){
2908                     break;
2909                 }
2910             }
2911             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2912             break;
2913         }
2914 
2915         case HCI_EVENT_PIN_CODE_REQUEST:
2916             hci_event_pin_code_request_get_bd_addr(packet, addr);
2917             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2918             if (!conn) break;
2919 
2920             hci_pairing_started(conn, false);
2921             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2922             if (!hci_stack->bondable ){
2923                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2924                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2925                 hci_run();
2926                 return;
2927             }
2928             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2929             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2930                 log_info("Level 4 required, but SC not supported -> abort");
2931                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2932                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2933                 hci_run();
2934                 return;
2935             }
2936             break;
2937 
2938         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2939             hci_event_io_capability_response_get_bd_addr(packet, addr);
2940             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2941             if (!conn) break;
2942 
2943             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2944             hci_pairing_started(conn, true);
2945             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2946             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2947 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2948             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2949 #endif
2950             break;
2951 
2952         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2953             hci_event_io_capability_response_get_bd_addr(packet, addr);
2954             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2955             if (!conn) break;
2956 
2957             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2958             hci_connection_timestamp(conn);
2959             hci_pairing_started(conn, true);
2960             break;
2961 
2962 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2963         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2964             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2965             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2966             if (!conn) break;
2967 
2968             hci_connection_timestamp(conn);
2969 
2970             hci_pairing_started(conn, true);
2971 
2972             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2973             break;
2974 #endif
2975 
2976         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2977             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2978             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2979             if (!conn) break;
2980             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2981                 if (hci_stack->ssp_auto_accept){
2982                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2983                 };
2984             } else {
2985                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2986                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2987                 // don't forward event to app
2988                 hci_run();
2989                 return;
2990             }
2991             break;
2992 
2993         case HCI_EVENT_USER_PASSKEY_REQUEST:
2994             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2995             if (hci_stack->ssp_auto_accept){
2996                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2997             };
2998             break;
2999 
3000         case HCI_EVENT_MODE_CHANGE:
3001             handle = hci_event_mode_change_get_handle(packet);
3002             conn = hci_connection_for_handle(handle);
3003             if (!conn) break;
3004             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3005             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3006             break;
3007 #endif
3008 
3009         case HCI_EVENT_ENCRYPTION_CHANGE:
3010             handle = hci_event_encryption_change_get_connection_handle(packet);
3011             conn = hci_connection_for_handle(handle);
3012             if (!conn) break;
3013             if (hci_event_encryption_change_get_status(packet) == 0u) {
3014                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3015                 if (encryption_enabled){
3016                     if (hci_is_le_connection(conn)){
3017                         // For LE, we accept connection as encrypted
3018                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3019                     }
3020 #ifdef ENABLE_CLASSIC
3021                     else {
3022 
3023                         // dedicated bonding: send result and disconnect
3024                         if (conn->bonding_flags & BONDING_DEDICATED){
3025                             conn->bonding_flags &= ~BONDING_DEDICATED;
3026                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3027                             conn->bonding_status = packet[2];
3028                             break;
3029                         }
3030 
3031                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3032                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3033                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3034                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3035                             log_info("SC during pairing, but only E0 now -> abort");
3036                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3037                             break;
3038                         }
3039 
3040                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3041                         if (connected_uses_aes_ccm){
3042                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3043                         }
3044 
3045 #ifdef ENABLE_TESTING_SUPPORT
3046                         // work around for issue with PTS dongle
3047                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3048 #endif
3049 
3050                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3051                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3052                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3053                         } else {
3054                             // if not, pretend everything is perfect
3055                             hci_handle_read_encryption_key_size_complete(conn, 16);
3056                         }
3057                     }
3058 #endif
3059                 } else {
3060                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3061                 }
3062             }
3063 
3064             break;
3065 
3066 #ifdef ENABLE_CLASSIC
3067         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3068             handle = hci_event_authentication_complete_get_connection_handle(packet);
3069             conn = hci_connection_for_handle(handle);
3070             if (!conn) break;
3071 
3072             // clear authentication active flag
3073             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3074             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3075 
3076             // authenticated only if auth status == 0
3077             if (hci_event_authentication_complete_get_status(packet) == 0){
3078                 // authenticated
3079                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3080 
3081                 // If not already encrypted, start encryption
3082                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3083                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3084                     break;
3085                 }
3086             }
3087 
3088             // emit updated security level
3089             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3090             break;
3091 
3092         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3093             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3094             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3095             if (!conn) break;
3096 
3097             // treat successfully paired connection as authenticated
3098             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3099                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3100             }
3101 
3102             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3103             break;
3104 #endif
3105 
3106         // HCI_EVENT_DISCONNECTION_COMPLETE
3107         // has been split, to first notify stack before shutting connection down
3108         // see end of function, too.
3109         case HCI_EVENT_DISCONNECTION_COMPLETE:
3110             if (packet[2]) break;   // status != 0
3111             handle = little_endian_read_16(packet, 3);
3112             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3113             if (hci_stack->acl_fragmentation_total_size > 0u) {
3114                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3115                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3116                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3117                     hci_stack->acl_fragmentation_total_size = 0;
3118                     hci_stack->acl_fragmentation_pos = 0;
3119                     if (release_buffer){
3120                         hci_release_packet_buffer();
3121                     }
3122                 }
3123             }
3124 
3125             conn = hci_connection_for_handle(handle);
3126             if (!conn) break;
3127 #ifdef ENABLE_CLASSIC
3128             // pairing failed if it was ongoing
3129             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3130 #endif
3131 
3132             // emit dedicatd bonding event
3133             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3134                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3135             }
3136 
3137             // mark connection for shutdown, stop timers, reset state
3138             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3139             hci_connection_stop_timer(conn);
3140             hci_connection_init(conn);
3141 
3142 #ifdef ENABLE_BLE
3143 #ifdef ENABLE_LE_PERIPHERAL
3144             // re-enable advertisements for le connections if active
3145             if (hci_is_le_connection(conn)){
3146                 hci_update_advertisements_enabled_for_current_roles();
3147             }
3148 #endif
3149 #endif
3150             break;
3151 
3152         case HCI_EVENT_HARDWARE_ERROR:
3153             log_error("Hardware Error: 0x%02x", packet[2]);
3154             if (hci_stack->hardware_error_callback){
3155                 (*hci_stack->hardware_error_callback)(packet[2]);
3156             } else {
3157                 // if no special requests, just reboot stack
3158                 hci_power_control_off();
3159                 hci_power_control_on();
3160             }
3161             break;
3162 
3163 #ifdef ENABLE_CLASSIC
3164         case HCI_EVENT_ROLE_CHANGE:
3165             if (packet[2]) break;   // status != 0
3166             reverse_bd_addr(&packet[3], addr);
3167             addr_type = BD_ADDR_TYPE_ACL;
3168             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3169             if (!conn) break;
3170             conn->role = packet[9];
3171             break;
3172 #endif
3173 
3174         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3175             // release packet buffer only for asynchronous transport and if there are not further fragements
3176             if (hci_transport_synchronous()) {
3177                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3178                 return; // instead of break: to avoid re-entering hci_run()
3179             }
3180             hci_stack->acl_fragmentation_tx_active = 0;
3181             if (hci_stack->acl_fragmentation_total_size) break;
3182             hci_release_packet_buffer();
3183 
3184             // L2CAP receives this event via the hci_emit_event below
3185 
3186 #ifdef ENABLE_CLASSIC
3187             // For SCO, we do the can_send_now_check here
3188             hci_notify_if_sco_can_send_now();
3189 #endif
3190             break;
3191 
3192 #ifdef ENABLE_CLASSIC
3193         case HCI_EVENT_SCO_CAN_SEND_NOW:
3194             // For SCO, we do the can_send_now_check here
3195             hci_stack->sco_can_send_now = true;
3196             hci_notify_if_sco_can_send_now();
3197             return;
3198 
3199         // explode inquriy results for easier consumption
3200         case HCI_EVENT_INQUIRY_RESULT:
3201         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3202         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3203             gap_inquiry_explode(packet, size);
3204             break;
3205 #endif
3206 
3207 #ifdef ENABLE_BLE
3208         case HCI_EVENT_LE_META:
3209             switch (packet[2]){
3210 #ifdef ENABLE_LE_CENTRAL
3211                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3212                     // log_info("advertising report received");
3213                     if (!hci_stack->le_scanning_enabled) break;
3214                     le_handle_advertisement_report(packet, size);
3215                     break;
3216 #endif
3217                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3218 					event_handle_le_connection_complete(packet);
3219                     break;
3220 
3221                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3222                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3223                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3224                     conn = hci_connection_for_handle(handle);
3225                     if (!conn) break;
3226                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3227                     break;
3228 
3229                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3230                     // connection
3231                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3232                     conn = hci_connection_for_handle(handle);
3233                     if (conn) {
3234                         // read arguments
3235                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3236                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3237                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3238                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3239 
3240                         // validate against current connection parameter range
3241                         le_connection_parameter_range_t existing_range;
3242                         gap_get_connection_parameter_range(&existing_range);
3243                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3244                         if (update_parameter){
3245                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3246                             conn->le_conn_interval_min = le_conn_interval_min;
3247                             conn->le_conn_interval_max = le_conn_interval_max;
3248                             conn->le_conn_latency = le_conn_latency;
3249                             conn->le_supervision_timeout = le_supervision_timeout;
3250                         } else {
3251                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3252                         }
3253                     }
3254                     break;
3255 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3256                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3257                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3258                     conn = hci_connection_for_handle(handle);
3259                     if (conn) {
3260                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3261                     }
3262                     break;
3263 #endif
3264                 default:
3265                     break;
3266             }
3267             break;
3268 #endif
3269         case HCI_EVENT_VENDOR_SPECIFIC:
3270             // Vendor specific commands often create vendor specific event instead of num completed packets
3271             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3272             switch (hci_stack->manufacturer){
3273                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3274                     hci_stack->num_cmd_packets = 1;
3275                     break;
3276                 default:
3277                     break;
3278             }
3279             break;
3280         default:
3281             break;
3282     }
3283 
3284     handle_event_for_current_stack_state(packet, size);
3285 
3286     // notify upper stack
3287 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3288 
3289     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3290     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3291 		handle = little_endian_read_16(packet, 3);
3292 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3293 		// discard connection if app did not trigger a reconnect in the event handler
3294 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3295 			hci_shutdown_connection(aConn);
3296 		}
3297     }
3298 
3299 	// execute main loop
3300 	hci_run();
3301 }
3302 
3303 #ifdef ENABLE_CLASSIC
3304 
3305 #ifdef ENABLE_SCO_OVER_HCI
3306 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3307 static void sco_schedule_tx(hci_connection_t * conn);
3308 
3309 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3310     log_debug("SCO TX Timeout");
3311     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3312     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3313     if (!conn) return;
3314 
3315     // trigger send
3316     conn->sco_tx_ready = 1;
3317     // extra packet if CVSD but SCO buffer is too short
3318     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3319         conn->sco_tx_ready++;
3320     }
3321     hci_notify_if_sco_can_send_now();
3322 }
3323 
3324 
3325 #define SCO_TX_AFTER_RX_MS (6)
3326 
3327 static void sco_schedule_tx(hci_connection_t * conn){
3328 
3329     uint32_t now = btstack_run_loop_get_time_ms();
3330     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3331     int time_delta_ms = sco_tx_ms - now;
3332 
3333     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3334 
3335     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3336     btstack_run_loop_remove_timer(timer);
3337     btstack_run_loop_set_timer(timer, time_delta_ms);
3338     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3339     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3340     btstack_run_loop_add_timer(timer);
3341 }
3342 #endif
3343 
3344 static void sco_handler(uint8_t * packet, uint16_t size){
3345     // lookup connection struct
3346     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3347     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3348     if (!conn) return;
3349 
3350 #ifdef ENABLE_SCO_OVER_HCI
3351     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3352     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3353         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3354             packet[2] = 0x3c;
3355             memmove(&packet[3], &packet[23], 63);
3356             size = 63;
3357         }
3358     }
3359 
3360     if (hci_have_usb_transport()){
3361         // Nothing to do
3362     } else {
3363         // 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);
3364         if (hci_stack->synchronous_flow_control_enabled == 0){
3365             uint32_t now = btstack_run_loop_get_time_ms();
3366 
3367             if (!conn->sco_rx_valid){
3368                 // ignore first 10 packets
3369                 conn->sco_rx_count++;
3370                 // log_debug("sco rx count %u", conn->sco_rx_count);
3371                 if (conn->sco_rx_count == 10) {
3372                     // use first timestamp as is and pretent it just started
3373                     conn->sco_rx_ms = now;
3374                     conn->sco_rx_valid = 1;
3375                     conn->sco_rx_count = 0;
3376                     sco_schedule_tx(conn);
3377                 }
3378             } else {
3379                 // track expected arrival timme
3380                 conn->sco_rx_count++;
3381                 conn->sco_rx_ms += 7;
3382                 int delta = (int32_t) (now - conn->sco_rx_ms);
3383                 if (delta > 0){
3384                     conn->sco_rx_ms++;
3385                 }
3386                 // log_debug("sco rx %u", conn->sco_rx_ms);
3387                 sco_schedule_tx(conn);
3388             }
3389         }
3390     }
3391 #endif
3392 
3393     // deliver to app
3394     if (hci_stack->sco_packet_handler) {
3395         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3396     }
3397 
3398 #ifdef HAVE_SCO_TRANSPORT
3399     // We can send one packet for each received packet
3400     conn->sco_tx_ready++;
3401     hci_notify_if_sco_can_send_now();
3402 #endif
3403 
3404 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3405     conn->num_packets_completed++;
3406     hci_stack->host_completed_packets = 1;
3407     hci_run();
3408 #endif
3409 }
3410 #endif
3411 
3412 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3413     hci_dump_packet(packet_type, 1, packet, size);
3414     switch (packet_type) {
3415         case HCI_EVENT_PACKET:
3416             event_handler(packet, size);
3417             break;
3418         case HCI_ACL_DATA_PACKET:
3419             acl_handler(packet, size);
3420             break;
3421 #ifdef ENABLE_CLASSIC
3422         case HCI_SCO_DATA_PACKET:
3423             sco_handler(packet, size);
3424             break;
3425 #endif
3426         default:
3427             break;
3428     }
3429 }
3430 
3431 /**
3432  * @brief Add event packet handler.
3433  */
3434 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3435     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3436 }
3437 
3438 
3439 /** Register HCI packet handlers */
3440 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3441     hci_stack->acl_packet_handler = handler;
3442 }
3443 
3444 #ifdef ENABLE_CLASSIC
3445 /**
3446  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3447  */
3448 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3449     hci_stack->sco_packet_handler = handler;
3450 }
3451 #endif
3452 
3453 static void hci_state_reset(void){
3454     // no connections yet
3455     hci_stack->connections = NULL;
3456 
3457     // keep discoverable/connectable as this has been requested by the client(s)
3458     // hci_stack->discoverable = 0;
3459     // hci_stack->connectable = 0;
3460     // hci_stack->bondable = 1;
3461     // hci_stack->own_addr_type = 0;
3462 
3463     // buffer is free
3464     hci_stack->hci_packet_buffer_reserved = false;
3465 
3466     // no pending cmds
3467     hci_stack->decline_reason = 0;
3468 
3469     hci_stack->secure_connections_active = false;
3470 
3471 #ifdef ENABLE_CLASSIC
3472     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3473     hci_stack->gap_tasks =
3474             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3475             GAP_TASK_SET_CLASS_OF_DEVICE |
3476             GAP_TASK_SET_LOCAL_NAME |
3477             GAP_TASK_SET_EIR_DATA |
3478             GAP_TASK_WRITE_SCAN_ENABLE;
3479 #endif
3480 
3481 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3482     hci_stack->classic_read_local_oob_data = true;
3483     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3484 #endif
3485 
3486     // LE
3487 #ifdef ENABLE_BLE
3488     memset(hci_stack->le_random_address, 0, 6);
3489     hci_stack->le_random_address_set = 0;
3490 #endif
3491 #ifdef ENABLE_LE_CENTRAL
3492     hci_stack->le_scanning_active  = false;
3493     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3494     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3495     hci_stack->le_whitelist_capacity = 0;
3496 #endif
3497 #ifdef ENABLE_LE_PERIPHERAL
3498     hci_stack->le_advertisements_active = false;
3499     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3500         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3501     }
3502     if (hci_stack->le_advertisements_data != NULL){
3503         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3504     }
3505 #endif
3506 }
3507 
3508 #ifdef ENABLE_CLASSIC
3509 /**
3510  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3511  */
3512 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3513     // store and open remote device db
3514     hci_stack->link_key_db = link_key_db;
3515     if (hci_stack->link_key_db) {
3516         hci_stack->link_key_db->open();
3517     }
3518 }
3519 #endif
3520 
3521 void hci_init(const hci_transport_t *transport, const void *config){
3522 
3523 #ifdef HAVE_MALLOC
3524     if (!hci_stack) {
3525         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3526     }
3527 #else
3528     hci_stack = &hci_stack_static;
3529 #endif
3530     memset(hci_stack, 0, sizeof(hci_stack_t));
3531 
3532     // reference to use transport layer implementation
3533     hci_stack->hci_transport = transport;
3534 
3535     // reference to used config
3536     hci_stack->config = config;
3537 
3538     // setup pointer for outgoing packet buffer
3539     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3540 
3541     // max acl payload size defined in config.h
3542     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3543 
3544     // register packet handlers with transport
3545     transport->register_packet_handler(&packet_handler);
3546 
3547     hci_stack->state = HCI_STATE_OFF;
3548 
3549     // class of device
3550     hci_stack->class_of_device = 0x007a020c; // Smartphone
3551 
3552     // bondable by default
3553     hci_stack->bondable = 1;
3554 
3555 #ifdef ENABLE_CLASSIC
3556     // classic name
3557     hci_stack->local_name = default_classic_name;
3558 
3559     // Master slave policy
3560     hci_stack->master_slave_policy = 1;
3561 
3562     // Allow Role Switch
3563     hci_stack->allow_role_switch = 1;
3564 
3565     // Default / minimum security level = 2
3566     hci_stack->gap_security_level = LEVEL_2;
3567 
3568     // Default Security Mode 4
3569     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3570 
3571     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3572     hci_stack->gap_required_encyrption_key_size = 7;
3573 
3574     // Link Supervision Timeout
3575     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3576 
3577 #endif
3578 
3579     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3580     hci_stack->ssp_enable = 1;
3581     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3582     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3583     hci_stack->ssp_auto_accept = 1;
3584 
3585     // Secure Connections: enable (requires support from Controller)
3586     hci_stack->secure_connections_enable = true;
3587 
3588     // voice setting - signed 16 bit pcm data with CVSD over the air
3589     hci_stack->sco_voice_setting = 0x60;
3590 
3591 #ifdef ENABLE_LE_CENTRAL
3592     // connection parameter to use for outgoing connections
3593     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3594     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3595     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3596     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3597     hci_stack->le_connection_latency      = 4;         // 4
3598     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3599     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3600     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3601 
3602     // default LE Scanning
3603     hci_stack->le_scan_type     =   0x1; // active
3604     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3605     hci_stack->le_scan_window   =  0x30; //  30 ms
3606 #endif
3607 
3608 #ifdef ENABLE_LE_PERIPHERAL
3609     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3610 #endif
3611 
3612     // connection parameter range used to answer connection parameter update requests in l2cap
3613     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3614     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3615     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3616     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3617     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3618     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3619 
3620     hci_state_reset();
3621 }
3622 
3623 void hci_deinit(void){
3624 #ifdef HAVE_MALLOC
3625     if (hci_stack) {
3626         free(hci_stack);
3627     }
3628 #endif
3629     hci_stack = NULL;
3630 
3631 #ifdef ENABLE_CLASSIC
3632     disable_l2cap_timeouts = 0;
3633 #endif
3634 }
3635 
3636 /**
3637  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3638  */
3639 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3640     hci_stack->chipset = chipset_driver;
3641 
3642     // reset chipset driver - init is also called on power_up
3643     if (hci_stack->chipset && hci_stack->chipset->init){
3644         hci_stack->chipset->init(hci_stack->config);
3645     }
3646 }
3647 
3648 /**
3649  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3650  */
3651 void hci_set_control(const btstack_control_t *hardware_control){
3652     // references to used control implementation
3653     hci_stack->control = hardware_control;
3654     // init with transport config
3655     hardware_control->init(hci_stack->config);
3656 }
3657 
3658 void hci_close(void){
3659 
3660 #ifdef ENABLE_CLASSIC
3661     // close remote device db
3662     if (hci_stack->link_key_db) {
3663         hci_stack->link_key_db->close();
3664     }
3665 #endif
3666 
3667     btstack_linked_list_iterator_t lit;
3668     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3669     while (btstack_linked_list_iterator_has_next(&lit)){
3670         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3671         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3672         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3673         hci_shutdown_connection(connection);
3674     }
3675 
3676     hci_power_control(HCI_POWER_OFF);
3677 
3678 #ifdef HAVE_MALLOC
3679     free(hci_stack);
3680 #endif
3681     hci_stack = NULL;
3682 }
3683 
3684 #ifdef HAVE_SCO_TRANSPORT
3685 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3686     hci_stack->sco_transport = sco_transport;
3687     sco_transport->register_packet_handler(&packet_handler);
3688 }
3689 #endif
3690 
3691 #ifdef ENABLE_CLASSIC
3692 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3693     // validate ranage and set
3694     if (encryption_key_size < 7)  return;
3695     if (encryption_key_size > 16) return;
3696     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3697 }
3698 
3699 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3700     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3701         hci_stack->gap_security_mode = security_mode;
3702         return ERROR_CODE_SUCCESS;
3703     } else {
3704         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3705     }
3706 }
3707 
3708 gap_security_mode_t gap_get_security_mode(void){
3709     return hci_stack->gap_security_mode;
3710 }
3711 
3712 void gap_set_security_level(gap_security_level_t security_level){
3713     hci_stack->gap_security_level = security_level;
3714 }
3715 
3716 gap_security_level_t gap_get_security_level(void){
3717     if (hci_stack->gap_secure_connections_only_mode){
3718         return LEVEL_4;
3719     }
3720     return hci_stack->gap_security_level;
3721 }
3722 
3723 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3724     hci_stack->gap_minimal_service_security_level = security_level;
3725 }
3726 
3727 void gap_set_secure_connections_only_mode(bool enable){
3728     hci_stack->gap_secure_connections_only_mode = enable;
3729 }
3730 
3731 bool gap_get_secure_connections_only_mode(void){
3732     return hci_stack->gap_secure_connections_only_mode;
3733 }
3734 #endif
3735 
3736 #ifdef ENABLE_CLASSIC
3737 void gap_set_class_of_device(uint32_t class_of_device){
3738     hci_stack->class_of_device = class_of_device;
3739     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3740     hci_run();
3741 }
3742 
3743 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3744     hci_stack->default_link_policy_settings = default_link_policy_settings;
3745     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3746     hci_run();
3747 }
3748 
3749 void gap_set_allow_role_switch(bool allow_role_switch){
3750     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3751 }
3752 
3753 uint8_t hci_get_allow_role_switch(void){
3754     return  hci_stack->allow_role_switch;
3755 }
3756 
3757 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3758     hci_stack->link_supervision_timeout = link_supervision_timeout;
3759 }
3760 
3761 void hci_disable_l2cap_timeout_check(void){
3762     disable_l2cap_timeouts = 1;
3763 }
3764 #endif
3765 
3766 #ifndef HAVE_HOST_CONTROLLER_API
3767 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3768 void hci_set_bd_addr(bd_addr_t addr){
3769     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3770     hci_stack->custom_bd_addr_set = 1;
3771 }
3772 #endif
3773 
3774 // State-Module-Driver overview
3775 // state                    module  low-level
3776 // HCI_STATE_OFF             off      close
3777 // HCI_STATE_INITIALIZING,   on       open
3778 // HCI_STATE_WORKING,        on       open
3779 // HCI_STATE_HALTING,        on       open
3780 // HCI_STATE_SLEEPING,    off/sleep   close
3781 // HCI_STATE_FALLING_ASLEEP  on       open
3782 
3783 static int hci_power_control_on(void){
3784 
3785     // power on
3786     int err = 0;
3787     if (hci_stack->control && hci_stack->control->on){
3788         err = (*hci_stack->control->on)();
3789     }
3790     if (err){
3791         log_error( "POWER_ON failed");
3792         hci_emit_hci_open_failed();
3793         return err;
3794     }
3795 
3796     // int chipset driver
3797     if (hci_stack->chipset && hci_stack->chipset->init){
3798         hci_stack->chipset->init(hci_stack->config);
3799     }
3800 
3801     // init transport
3802     if (hci_stack->hci_transport->init){
3803         hci_stack->hci_transport->init(hci_stack->config);
3804     }
3805 
3806     // open transport
3807     err = hci_stack->hci_transport->open();
3808     if (err){
3809         log_error( "HCI_INIT failed, turning Bluetooth off again");
3810         if (hci_stack->control && hci_stack->control->off){
3811             (*hci_stack->control->off)();
3812         }
3813         hci_emit_hci_open_failed();
3814         return err;
3815     }
3816     return 0;
3817 }
3818 
3819 static void hci_power_control_off(void){
3820 
3821     log_info("hci_power_control_off");
3822 
3823     // close low-level device
3824     hci_stack->hci_transport->close();
3825 
3826     log_info("hci_power_control_off - hci_transport closed");
3827 
3828     // power off
3829     if (hci_stack->control && hci_stack->control->off){
3830         (*hci_stack->control->off)();
3831     }
3832 
3833     log_info("hci_power_control_off - control closed");
3834 
3835     hci_stack->state = HCI_STATE_OFF;
3836 }
3837 
3838 static void hci_power_control_sleep(void){
3839 
3840     log_info("hci_power_control_sleep");
3841 
3842 #if 0
3843     // don't close serial port during sleep
3844 
3845     // close low-level device
3846     hci_stack->hci_transport->close(hci_stack->config);
3847 #endif
3848 
3849     // sleep mode
3850     if (hci_stack->control && hci_stack->control->sleep){
3851         (*hci_stack->control->sleep)();
3852     }
3853 
3854     hci_stack->state = HCI_STATE_SLEEPING;
3855 }
3856 
3857 static int hci_power_control_wake(void){
3858 
3859     log_info("hci_power_control_wake");
3860 
3861     // wake on
3862     if (hci_stack->control && hci_stack->control->wake){
3863         (*hci_stack->control->wake)();
3864     }
3865 
3866 #if 0
3867     // open low-level device
3868     int err = hci_stack->hci_transport->open(hci_stack->config);
3869     if (err){
3870         log_error( "HCI_INIT failed, turning Bluetooth off again");
3871         if (hci_stack->control && hci_stack->control->off){
3872             (*hci_stack->control->off)();
3873         }
3874         hci_emit_hci_open_failed();
3875         return err;
3876     }
3877 #endif
3878 
3879     return 0;
3880 }
3881 
3882 static void hci_power_transition_to_initializing(void){
3883     // set up state machine
3884     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3885     hci_stack->hci_packet_buffer_reserved = false;
3886     hci_stack->state = HCI_STATE_INITIALIZING;
3887     hci_stack->substate = HCI_INIT_SEND_RESET;
3888 }
3889 
3890 // returns error
3891 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3892     int err;
3893     switch (power_mode){
3894         case HCI_POWER_ON:
3895             err = hci_power_control_on();
3896             if (err != 0) {
3897                 log_error("hci_power_control_on() error %d", err);
3898                 return err;
3899             }
3900             hci_power_transition_to_initializing();
3901             break;
3902         case HCI_POWER_OFF:
3903             // do nothing
3904             break;
3905         case HCI_POWER_SLEEP:
3906             // do nothing (with SLEEP == OFF)
3907             break;
3908         default:
3909             btstack_assert(false);
3910             break;
3911     }
3912     return ERROR_CODE_SUCCESS;
3913 }
3914 
3915 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3916     switch (power_mode){
3917         case HCI_POWER_ON:
3918             // do nothing
3919             break;
3920         case HCI_POWER_OFF:
3921             // no connections yet, just turn it off
3922             hci_power_control_off();
3923             break;
3924         case HCI_POWER_SLEEP:
3925             // no connections yet, just turn it off
3926             hci_power_control_sleep();
3927             break;
3928         default:
3929             btstack_assert(false);
3930             break;
3931     }
3932     return ERROR_CODE_SUCCESS;
3933 }
3934 
3935 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3936     switch (power_mode){
3937         case HCI_POWER_ON:
3938             // do nothing
3939             break;
3940         case HCI_POWER_OFF:
3941             // see hci_run
3942             hci_stack->state = HCI_STATE_HALTING;
3943             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3944             break;
3945         case HCI_POWER_SLEEP:
3946             // see hci_run
3947             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3948             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3949             break;
3950         default:
3951             btstack_assert(false);
3952             break;
3953     }
3954     return ERROR_CODE_SUCCESS;
3955 }
3956 
3957 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3958     switch (power_mode){
3959         case HCI_POWER_ON:
3960             hci_power_transition_to_initializing();
3961             break;
3962         case HCI_POWER_OFF:
3963             // do nothing
3964             break;
3965         case HCI_POWER_SLEEP:
3966             // see hci_run
3967             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3968             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3969             break;
3970         default:
3971             btstack_assert(false);
3972             break;
3973     }
3974     return ERROR_CODE_SUCCESS;
3975 }
3976 
3977 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3978     switch (power_mode){
3979         case HCI_POWER_ON:
3980             hci_power_transition_to_initializing();
3981             break;
3982         case HCI_POWER_OFF:
3983             // see hci_run
3984             hci_stack->state = HCI_STATE_HALTING;
3985             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3986             break;
3987         case HCI_POWER_SLEEP:
3988             // do nothing
3989             break;
3990         default:
3991             btstack_assert(false);
3992             break;
3993     }
3994     return ERROR_CODE_SUCCESS;
3995 }
3996 
3997 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3998     int err;
3999     switch (power_mode){
4000         case HCI_POWER_ON:
4001             err = hci_power_control_wake();
4002             if (err) return err;
4003             hci_power_transition_to_initializing();
4004             break;
4005         case HCI_POWER_OFF:
4006             hci_stack->state = HCI_STATE_HALTING;
4007             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4008             break;
4009         case HCI_POWER_SLEEP:
4010             // do nothing
4011             break;
4012         default:
4013             btstack_assert(false);
4014             break;
4015     }
4016     return ERROR_CODE_SUCCESS;
4017 }
4018 
4019 int hci_power_control(HCI_POWER_MODE power_mode){
4020     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4021     int err = 0;
4022     switch (hci_stack->state){
4023         case HCI_STATE_OFF:
4024             err = hci_power_control_state_off(power_mode);
4025             break;
4026         case HCI_STATE_INITIALIZING:
4027             err = hci_power_control_state_initializing(power_mode);
4028             break;
4029         case HCI_STATE_WORKING:
4030             err = hci_power_control_state_working(power_mode);
4031             break;
4032         case HCI_STATE_HALTING:
4033             err = hci_power_control_state_halting(power_mode);
4034             break;
4035         case HCI_STATE_FALLING_ASLEEP:
4036             err = hci_power_control_state_falling_asleep(power_mode);
4037             break;
4038         case HCI_STATE_SLEEPING:
4039             err = hci_power_control_state_sleeping(power_mode);
4040             break;
4041         default:
4042             btstack_assert(false);
4043             break;
4044     }
4045     if (err != 0){
4046         return err;
4047     }
4048 
4049     // create internal event
4050 	hci_emit_state();
4051 
4052 	// trigger next/first action
4053 	hci_run();
4054 
4055     return 0;
4056 }
4057 
4058 
4059 #ifdef ENABLE_CLASSIC
4060 
4061 static void hci_update_scan_enable(void){
4062     // 2 = page scan, 1 = inq scan
4063     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4064     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4065     hci_run();
4066 }
4067 
4068 void gap_discoverable_control(uint8_t enable){
4069     if (enable) enable = 1; // normalize argument
4070 
4071     if (hci_stack->discoverable == enable){
4072         hci_emit_discoverable_enabled(hci_stack->discoverable);
4073         return;
4074     }
4075 
4076     hci_stack->discoverable = enable;
4077     hci_update_scan_enable();
4078 }
4079 
4080 void gap_connectable_control(uint8_t enable){
4081     if (enable) enable = 1; // normalize argument
4082 
4083     // don't emit event
4084     if (hci_stack->connectable == enable) return;
4085 
4086     hci_stack->connectable = enable;
4087     hci_update_scan_enable();
4088 }
4089 #endif
4090 
4091 void gap_local_bd_addr(bd_addr_t address_buffer){
4092     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4093 }
4094 
4095 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4096 static void hci_host_num_completed_packets(void){
4097 
4098     // create packet manually as arrays are not supported and num_commands should not get reduced
4099     hci_reserve_packet_buffer();
4100     uint8_t * packet = hci_get_outgoing_packet_buffer();
4101 
4102     uint16_t size = 0;
4103     uint16_t num_handles = 0;
4104     packet[size++] = 0x35;
4105     packet[size++] = 0x0c;
4106     size++;  // skip param len
4107     size++;  // skip num handles
4108 
4109     // add { handle, packets } entries
4110     btstack_linked_item_t * it;
4111     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4112         hci_connection_t * connection = (hci_connection_t *) it;
4113         if (connection->num_packets_completed){
4114             little_endian_store_16(packet, size, connection->con_handle);
4115             size += 2;
4116             little_endian_store_16(packet, size, connection->num_packets_completed);
4117             size += 2;
4118             //
4119             num_handles++;
4120             connection->num_packets_completed = 0;
4121         }
4122     }
4123 
4124     packet[2] = size - 3;
4125     packet[3] = num_handles;
4126 
4127     hci_stack->host_completed_packets = 0;
4128 
4129     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4130     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4131 
4132     // release packet buffer for synchronous transport implementations
4133     if (hci_transport_synchronous()){
4134         hci_release_packet_buffer();
4135         hci_emit_transport_packet_sent();
4136     }
4137 }
4138 #endif
4139 
4140 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4141     UNUSED(ds);
4142     hci_stack->substate = HCI_HALTING_CLOSE;
4143     // allow packet handlers to defer final shutdown
4144     hci_emit_state();
4145     hci_run();
4146 }
4147 
4148 static bool hci_run_acl_fragments(void){
4149     if (hci_stack->acl_fragmentation_total_size > 0u) {
4150         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4151         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4152         if (connection) {
4153             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4154                 hci_send_acl_packet_fragments(connection);
4155                 return true;
4156             }
4157         } else {
4158             // connection gone -> discard further fragments
4159             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4160             hci_stack->acl_fragmentation_total_size = 0;
4161             hci_stack->acl_fragmentation_pos = 0;
4162         }
4163     }
4164     return false;
4165 }
4166 
4167 #ifdef ENABLE_CLASSIC
4168 static bool hci_run_general_gap_classic(void){
4169 
4170     // assert stack is working and classic is active
4171     if (hci_classic_supported() == false)      return false;
4172     if (hci_stack->state != HCI_STATE_WORKING) return false;
4173 
4174     // decline incoming connections
4175     if (hci_stack->decline_reason){
4176         uint8_t reason = hci_stack->decline_reason;
4177         hci_stack->decline_reason = 0;
4178         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4179         return true;
4180     }
4181 
4182     if (hci_stack->gap_tasks != 0){
4183         hci_run_gap_tasks_classic();
4184         return true;
4185     }
4186 
4187     // start/stop inquiry
4188     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4189         uint8_t duration = hci_stack->inquiry_state;
4190         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4191         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4192         return true;
4193     }
4194     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4195         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4196         hci_send_cmd(&hci_inquiry_cancel);
4197         return true;
4198     }
4199     // remote name request
4200     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4201         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4202         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4203                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4204         return true;
4205     }
4206 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4207     // Local OOB data
4208     if (hci_stack->classic_read_local_oob_data){
4209         hci_stack->classic_read_local_oob_data = false;
4210         if (hci_stack->local_supported_commands[1] & 0x10u){
4211             hci_send_cmd(&hci_read_local_extended_oob_data);
4212         } else {
4213             hci_send_cmd(&hci_read_local_oob_data);
4214         }
4215     }
4216 #endif
4217     // pairing
4218     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4219         uint8_t state = hci_stack->gap_pairing_state;
4220         uint8_t pin_code[16];
4221         switch (state){
4222             case GAP_PAIRING_STATE_SEND_PIN:
4223                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4224                 memset(pin_code, 0, 16);
4225                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4226                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4227                 break;
4228             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4229                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4230                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4231                 break;
4232             case GAP_PAIRING_STATE_SEND_PASSKEY:
4233                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4234                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4235                 break;
4236             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4237                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4238                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4239                 break;
4240             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4241                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4242                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4243                 break;
4244             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4245                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4246                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4247                 break;
4248             default:
4249                 break;
4250         }
4251         return true;
4252     }
4253     return false;
4254 }
4255 #endif
4256 
4257 #ifdef ENABLE_BLE
4258 static bool hci_run_general_gap_le(void){
4259 
4260     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4261 
4262     if (hci_stack->state != HCI_STATE_WORKING) return false;
4263     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4264 
4265 
4266     // Phase 1: collect what to stop
4267 
4268     bool scanning_stop = false;
4269     bool connecting_stop = false;
4270     bool advertising_stop = false;
4271 
4272 #ifndef ENABLE_LE_CENTRAL
4273     UNUSED(scanning_stop);
4274     UNUSED(connecting_stop);
4275 #endif
4276 #ifndef ENABLE_LE_PERIPHERAL
4277     UNUSED(advertising_stop);
4278 #endif
4279 
4280     // check if whitelist needs modification
4281     bool whitelist_modification_pending = false;
4282     btstack_linked_list_iterator_t lit;
4283     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4284     while (btstack_linked_list_iterator_has_next(&lit)){
4285         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4286         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4287             whitelist_modification_pending = true;
4288             break;
4289         }
4290     }
4291     // check if resolving list needs modification
4292     bool resolving_list_modification_pending = false;
4293 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4294     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4295 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4296         resolving_list_modification_pending = true;
4297     }
4298 #endif
4299 
4300 #ifdef ENABLE_LE_CENTRAL
4301     // scanning control
4302     if (hci_stack->le_scanning_active) {
4303         // stop if:
4304         // - parameter change required
4305         // - it's disabled
4306         // - whitelist change required but used for scanning
4307         // - resolving list modified
4308         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4309         if ((hci_stack->le_scanning_param_update) ||
4310             !hci_stack->le_scanning_enabled ||
4311             scanning_uses_whitelist ||
4312             resolving_list_modification_pending){
4313 
4314             scanning_stop = true;
4315         }
4316     }
4317 #endif
4318 
4319 #ifdef ENABLE_LE_CENTRAL
4320     // connecting control
4321     bool connecting_with_whitelist;
4322     switch (hci_stack->le_connecting_state){
4323         case LE_CONNECTING_DIRECT:
4324         case LE_CONNECTING_WHITELIST:
4325             // stop connecting if:
4326             // - connecting uses white and whitelist modification pending
4327             // - if it got disabled
4328             // - resolving list modified
4329             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4330             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4331                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4332                 resolving_list_modification_pending) {
4333 
4334                 connecting_stop = true;
4335             }
4336             break;
4337         default:
4338             break;
4339     }
4340 #endif
4341 
4342 #ifdef ENABLE_LE_PERIPHERAL
4343     // le advertisement control
4344     if (hci_stack->le_advertisements_active){
4345         // stop if:
4346         // - parameter change required
4347         // - it's disabled
4348         // - whitelist change required but used for advertisement filter policy
4349         // - resolving list modified
4350         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4351         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4352         if (advertising_change ||
4353             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4354             (advertising_uses_whitelist & whitelist_modification_pending) ||
4355             resolving_list_modification_pending) {
4356 
4357             advertising_stop = true;
4358         }
4359     }
4360 #endif
4361 
4362 
4363     // Phase 2: stop everything that should be off during modifications
4364 
4365 #ifdef ENABLE_LE_CENTRAL
4366     if (scanning_stop){
4367         hci_stack->le_scanning_active = false;
4368         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4369         return true;
4370     }
4371 #endif
4372 
4373 #ifdef ENABLE_LE_CENTRAL
4374     if (connecting_stop){
4375         hci_send_cmd(&hci_le_create_connection_cancel);
4376         return true;
4377     }
4378 #endif
4379 
4380 #ifdef ENABLE_LE_PERIPHERAL
4381     if (advertising_stop){
4382         hci_stack->le_advertisements_active = false;
4383         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4384         return true;
4385     }
4386 #endif
4387 
4388     // Phase 3: modify
4389 
4390 #ifdef ENABLE_LE_CENTRAL
4391     if (hci_stack->le_scanning_param_update){
4392         hci_stack->le_scanning_param_update = false;
4393         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4394                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4395         return true;
4396     }
4397 #endif
4398 
4399 #ifdef ENABLE_LE_PERIPHERAL
4400     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4401         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4402         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4403         hci_send_cmd(&hci_le_set_advertising_parameters,
4404                      hci_stack->le_advertisements_interval_min,
4405                      hci_stack->le_advertisements_interval_max,
4406                      hci_stack->le_advertisements_type,
4407                      hci_stack->le_advertisements_own_addr_type,
4408                      hci_stack->le_advertisements_direct_address_type,
4409                      hci_stack->le_advertisements_direct_address,
4410                      hci_stack->le_advertisements_channel_map,
4411                      hci_stack->le_advertisements_filter_policy);
4412         return true;
4413     }
4414     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4415         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4416         uint8_t adv_data_clean[31];
4417         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4418         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4419                      hci_stack->le_advertisements_data_len);
4420         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4421         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4422         return true;
4423     }
4424     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4425         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4426         uint8_t scan_data_clean[31];
4427         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4428         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4429                      hci_stack->le_scan_response_data_len);
4430         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4431         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4432         return true;
4433     }
4434 #endif
4435 
4436 
4437 #ifdef ENABLE_LE_CENTRAL
4438     // if connect with whitelist was active and is not cancelled yet, wait until next time
4439     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4440 #endif
4441 
4442     // LE Whitelist Management
4443     if (whitelist_modification_pending){
4444         // add/remove entries
4445         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4446         while (btstack_linked_list_iterator_has_next(&lit)){
4447             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4448 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4449 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4450 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4451 				return true;
4452 			}
4453             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4454 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4455                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4456                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4457                 return true;
4458             }
4459             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4460 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4461 				btstack_memory_whitelist_entry_free(entry);
4462             }
4463         }
4464     }
4465 
4466 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4467     // LE Resolving List Management
4468     if (resolving_list_supported) {
4469 		uint16_t i;
4470 		switch (hci_stack->le_resolving_list_state) {
4471 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4472 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4473 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4474 				return true;
4475 			case LE_RESOLVING_LIST_READ_SIZE:
4476 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4477 				hci_send_cmd(&hci_le_read_resolving_list_size);
4478 				return true;
4479 			case LE_RESOLVING_LIST_SEND_CLEAR:
4480 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4481 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4482 							  sizeof(hci_stack->le_resolving_list_add_entries));
4483 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4484 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4485 				hci_send_cmd(&hci_le_clear_resolving_list);
4486 				return true;
4487 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4488 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4489 					uint8_t offset = i >> 3;
4490 					uint8_t mask = 1 << (i & 7);
4491 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4492 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4493 					bd_addr_t peer_identity_addreses;
4494 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4495 					sm_key_t peer_irk;
4496 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4497 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4498 
4499 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4500 					// trigger whitelist entry 'update' (work around for controller bug)
4501 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4502 					while (btstack_linked_list_iterator_has_next(&lit)) {
4503 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4504 						if (entry->address_type != peer_identity_addr_type) continue;
4505 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4506 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4507 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4508 					}
4509 #endif
4510 
4511 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4512 								 peer_identity_addreses);
4513 					return true;
4514 				}
4515 
4516 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4517 
4518 				/* fall through */
4519 
4520 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4521 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4522 					uint8_t offset = i >> 3;
4523 					uint8_t mask = 1 << (i & 7);
4524 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4525 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4526 					bd_addr_t peer_identity_addreses;
4527 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4528 					sm_key_t peer_irk;
4529 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4530 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4531 					const uint8_t *local_irk = gap_get_persistent_irk();
4532 					// command uses format specifier 'P' that stores 16-byte value without flip
4533 					uint8_t local_irk_flipped[16];
4534 					uint8_t peer_irk_flipped[16];
4535 					reverse_128(local_irk, local_irk_flipped);
4536 					reverse_128(peer_irk, peer_irk_flipped);
4537 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4538 								 peer_irk_flipped, local_irk_flipped);
4539 					return true;
4540 				}
4541 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4542 				break;
4543 
4544 			default:
4545 				break;
4546 		}
4547 	}
4548     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4549 #endif
4550 
4551     // Phase 4: restore state
4552 
4553 #ifdef ENABLE_LE_CENTRAL
4554     // re-start scanning
4555     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4556         hci_stack->le_scanning_active = true;
4557         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4558         return true;
4559     }
4560 #endif
4561 
4562 #ifdef ENABLE_LE_CENTRAL
4563     // re-start connecting
4564     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4565         bd_addr_t null_addr;
4566         memset(null_addr, 0, 6);
4567         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4568         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4569         hci_send_cmd(&hci_le_create_connection,
4570                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4571                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4572                      1,         // use whitelist
4573                      0,         // peer address type
4574                      null_addr, // peer bd addr
4575                      hci_stack->le_connection_own_addr_type,   // our addr type:
4576                      hci_stack->le_connection_interval_min,    // conn interval min
4577                      hci_stack->le_connection_interval_max,    // conn interval max
4578                      hci_stack->le_connection_latency,         // conn latency
4579                      hci_stack->le_supervision_timeout,        // conn latency
4580                      hci_stack->le_minimum_ce_length,          // min ce length
4581                      hci_stack->le_maximum_ce_length           // max ce length
4582         );
4583         return true;
4584     }
4585 #endif
4586 
4587 #ifdef ENABLE_LE_PERIPHERAL
4588     // re-start advertising
4589     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4590         // check if advertisements should be enabled given
4591         hci_stack->le_advertisements_active = true;
4592         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4593         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4594         return true;
4595     }
4596 #endif
4597 
4598     return false;
4599 }
4600 #endif
4601 
4602 static bool hci_run_general_pending_commands(void){
4603     btstack_linked_item_t * it;
4604     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4605         hci_connection_t * connection = (hci_connection_t *) it;
4606 
4607         switch(connection->state){
4608             case SEND_CREATE_CONNECTION:
4609                 switch(connection->address_type){
4610 #ifdef ENABLE_CLASSIC
4611                     case BD_ADDR_TYPE_ACL:
4612                         log_info("sending hci_create_connection");
4613                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4614                         break;
4615 #endif
4616                     default:
4617 #ifdef ENABLE_BLE
4618 #ifdef ENABLE_LE_CENTRAL
4619                         log_info("sending hci_le_create_connection");
4620                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4621                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4622                         hci_send_cmd(&hci_le_create_connection,
4623                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4624                                      hci_stack->le_connection_scan_window,      // conn scan windows
4625                                      0,         // don't use whitelist
4626                                      connection->address_type, // peer address type
4627                                      connection->address,      // peer bd addr
4628                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4629                                      hci_stack->le_connection_interval_min,    // conn interval min
4630                                      hci_stack->le_connection_interval_max,    // conn interval max
4631                                      hci_stack->le_connection_latency,         // conn latency
4632                                      hci_stack->le_supervision_timeout,        // conn latency
4633                                      hci_stack->le_minimum_ce_length,          // min ce length
4634                                      hci_stack->le_maximum_ce_length          // max ce length
4635                         );
4636                         connection->state = SENT_CREATE_CONNECTION;
4637 #endif
4638 #endif
4639                         break;
4640                 }
4641                 return true;
4642 
4643 #ifdef ENABLE_CLASSIC
4644             case RECEIVED_CONNECTION_REQUEST:
4645                 connection->role  = HCI_ROLE_SLAVE;
4646                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4647                     log_info("sending hci_accept_connection_request");
4648                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4649                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4650                 }
4651                 return true;
4652 #endif
4653 
4654 #ifdef ENABLE_BLE
4655 #ifdef ENABLE_LE_CENTRAL
4656             case SEND_CANCEL_CONNECTION:
4657                 connection->state = SENT_CANCEL_CONNECTION;
4658                 hci_send_cmd(&hci_le_create_connection_cancel);
4659                 return true;
4660 #endif
4661 #endif
4662             case SEND_DISCONNECT:
4663                 connection->state = SENT_DISCONNECT;
4664                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4665                 return true;
4666 
4667             default:
4668                 break;
4669         }
4670 
4671         // no further commands if connection is about to get shut down
4672         if (connection->state == SENT_DISCONNECT) continue;
4673 
4674         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4675             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4676             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4677             return true;
4678         }
4679 
4680 #ifdef ENABLE_CLASSIC
4681 
4682         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4683             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4684             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4685             return true;
4686         }
4687 
4688         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4689             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4690             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4691             return true;
4692         }
4693 
4694         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4695             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4696             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4697             return true;
4698         }
4699 
4700         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4701             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4702             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4703             return true;
4704         }
4705 
4706         // Handling link key request requires remote supported features
4707         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4708             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4709             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4710 
4711             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4712             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4713             if (have_link_key && security_level_sufficient){
4714                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4715             } else {
4716                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4717             }
4718             return true;
4719         }
4720 
4721         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4722             log_info("denying to pin request");
4723             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4724             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4725             return true;
4726         }
4727 
4728         // security assessment requires remote features
4729         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4730             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4731             hci_ssp_assess_security_on_io_cap_request(connection);
4732             // 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
4733         }
4734 
4735         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4736             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4737             // set authentication requirements:
4738             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4739             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4740             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4741             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4742                 authreq |= 1;
4743             }
4744             bool bonding = hci_stack->bondable;
4745             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4746                 // if we have received IO Cap Response, we're in responder role
4747                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4748                 if (bonding && !remote_bonding){
4749                     log_info("Remote not bonding, dropping local flag");
4750                     bonding = false;
4751                 }
4752             }
4753             if (bonding){
4754                 if (connection->bonding_flags & BONDING_DEDICATED){
4755                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4756                 } else {
4757                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4758                 }
4759             }
4760             uint8_t have_oob_data = 0;
4761 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4762             if (connection->classic_oob_c_192 != NULL){
4763                     have_oob_data |= 1;
4764             }
4765             if (connection->classic_oob_c_256 != NULL){
4766                 have_oob_data |= 2;
4767             }
4768 #endif
4769             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4770             return true;
4771         }
4772 
4773         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4774             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4775             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4776             return true;
4777         }
4778 
4779 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4780         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4781             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4782             const uint8_t zero[16] = { 0 };
4783             const uint8_t * r_192 = zero;
4784             const uint8_t * c_192 = zero;
4785             const uint8_t * r_256 = zero;
4786             const uint8_t * c_256 = zero;
4787             // verify P-256 OOB
4788             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4789                 c_256 = connection->classic_oob_c_256;
4790                 if (connection->classic_oob_r_256 != NULL) {
4791                     r_256 = connection->classic_oob_r_256;
4792                 }
4793             }
4794             // verify P-192 OOB
4795             if ((connection->classic_oob_c_192 != NULL)) {
4796                 c_192 = connection->classic_oob_c_192;
4797                 if (connection->classic_oob_r_192 != NULL) {
4798                     r_192 = connection->classic_oob_r_192;
4799                 }
4800             }
4801 
4802             // assess security
4803             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4804             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4805             if (need_level_4 && !can_reach_level_4){
4806                 log_info("Level 4 required, but not possible -> abort");
4807                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4808                 // send oob negative reply
4809                 c_256 = NULL;
4810                 c_192 = NULL;
4811             }
4812 
4813             // Reply
4814             if (c_256 != zero) {
4815                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4816             } else if (c_192 != zero){
4817                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4818             } else {
4819                 hci_stack->classic_oob_con_handle = connection->con_handle;
4820                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4821             }
4822             return true;
4823         }
4824 #endif
4825 
4826         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4827             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4828             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4829             return true;
4830         }
4831 
4832         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4833             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4834             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4835             return true;
4836         }
4837 
4838         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4839             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4840             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4841             return true;
4842         }
4843 
4844         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4845             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4846             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4847             connection->state = SENT_DISCONNECT;
4848             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4849             return true;
4850         }
4851 
4852         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4853             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4854             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4855             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4856             return true;
4857         }
4858 
4859         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4860             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4861             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4862             return true;
4863         }
4864         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4865             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4866             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4867             return true;
4868         }
4869 #endif
4870 
4871         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4872             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4873 #ifdef ENABLE_CLASSIC
4874             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4875 #endif
4876             if (connection->state != SENT_DISCONNECT){
4877                 connection->state = SENT_DISCONNECT;
4878                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4879                 return true;
4880             }
4881         }
4882 
4883 #ifdef ENABLE_CLASSIC
4884         uint16_t sniff_min_interval;
4885         switch (connection->sniff_min_interval){
4886             case 0:
4887                 break;
4888             case 0xffff:
4889                 connection->sniff_min_interval = 0;
4890                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4891                 return true;
4892             default:
4893                 sniff_min_interval = connection->sniff_min_interval;
4894                 connection->sniff_min_interval = 0;
4895                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4896                 return true;
4897         }
4898 
4899         if (connection->sniff_subrating_max_latency != 0xffff){
4900             uint16_t max_latency = connection->sniff_subrating_max_latency;
4901             connection->sniff_subrating_max_latency = 0;
4902             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4903             return true;
4904         }
4905 
4906         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4907             uint8_t service_type = (uint8_t) connection->qos_service_type;
4908             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4909             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);
4910             return true;
4911         }
4912 
4913         if (connection->request_role != HCI_ROLE_INVALID){
4914             hci_role_t role = connection->request_role;
4915             connection->request_role = HCI_ROLE_INVALID;
4916             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4917             return true;
4918         }
4919 #endif
4920 
4921 #ifdef ENABLE_BLE
4922         switch (connection->le_con_parameter_update_state){
4923             // response to L2CAP CON PARAMETER UPDATE REQUEST
4924             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4925                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4926                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4927                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4928                              0x0000, 0xffff);
4929                 return true;
4930             case CON_PARAMETER_UPDATE_REPLY:
4931                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4932                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4933                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4934                              0x0000, 0xffff);
4935                 return true;
4936             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4937                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4938                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4939                 return true;
4940             default:
4941                 break;
4942         }
4943         if (connection->le_phy_update_all_phys != 0xffu){
4944             uint8_t all_phys = connection->le_phy_update_all_phys;
4945             connection->le_phy_update_all_phys = 0xff;
4946             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);
4947             return true;
4948         }
4949 #endif
4950     }
4951     return false;
4952 }
4953 
4954 static void hci_run(void){
4955 
4956     bool done;
4957 
4958     // send continuation fragments first, as they block the prepared packet buffer
4959     done = hci_run_acl_fragments();
4960     if (done) return;
4961 
4962 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4963     // send host num completed packets next as they don't require num_cmd_packets > 0
4964     if (!hci_can_send_comand_packet_transport()) return;
4965     if (hci_stack->host_completed_packets){
4966         hci_host_num_completed_packets();
4967         return;
4968     }
4969 #endif
4970 
4971     if (!hci_can_send_command_packet_now()) return;
4972 
4973     // global/non-connection oriented commands
4974 
4975 
4976 #ifdef ENABLE_CLASSIC
4977     // general gap classic
4978     done = hci_run_general_gap_classic();
4979     if (done) return;
4980 #endif
4981 
4982 #ifdef ENABLE_BLE
4983     // general gap le
4984     done = hci_run_general_gap_le();
4985     if (done) return;
4986 #endif
4987 
4988     // send pending HCI commands
4989     done = hci_run_general_pending_commands();
4990     if (done) return;
4991 
4992     // stack state sub statemachines
4993     hci_connection_t * connection;
4994     switch (hci_stack->state){
4995         case HCI_STATE_INITIALIZING:
4996             hci_initializing_run();
4997             break;
4998 
4999         case HCI_STATE_HALTING:
5000 
5001             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5002             switch (hci_stack->substate){
5003                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5004                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5005 
5006 #ifdef ENABLE_BLE
5007 #ifdef ENABLE_LE_CENTRAL
5008                     // free whitelist entries
5009                     {
5010                         btstack_linked_list_iterator_t lit;
5011                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5012                         while (btstack_linked_list_iterator_has_next(&lit)){
5013                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5014                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5015                             btstack_memory_whitelist_entry_free(entry);
5016                         }
5017                     }
5018 #endif
5019 #endif
5020                     // close all open connections
5021                     connection =  (hci_connection_t *) hci_stack->connections;
5022                     if (connection){
5023                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5024                         if (!hci_can_send_command_packet_now()) return;
5025 
5026                         // check state
5027                         if (connection->state == SENT_DISCONNECT) return;
5028                         connection->state = SENT_DISCONNECT;
5029 
5030                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5031 
5032                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5033                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5034 
5035                         // ... which would be ignored anyway as we shutdown (free) the connection now
5036                         hci_shutdown_connection(connection);
5037 
5038                         // finally, send the disconnect command
5039                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5040                         return;
5041                     }
5042 
5043                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5044                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5045                         log_info("HCI_STATE_HALTING: wait 50 ms");
5046                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5047                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5048                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5049                         btstack_run_loop_add_timer(&hci_stack->timeout);
5050                         break;
5051                     }
5052 
5053                     /* fall through */
5054 
5055                 case HCI_HALTING_CLOSE:
5056                     log_info("HCI_STATE_HALTING, calling off");
5057 
5058                     // switch mode
5059                     hci_power_control_off();
5060 
5061                     log_info("HCI_STATE_HALTING, emitting state");
5062                     hci_emit_state();
5063                     log_info("HCI_STATE_HALTING, done");
5064                     break;
5065 
5066                 case HCI_HALTING_W4_TIMER:
5067                     // keep waiting
5068 
5069                     break;
5070                 default:
5071                     break;
5072             }
5073 
5074             break;
5075 
5076         case HCI_STATE_FALLING_ASLEEP:
5077             switch(hci_stack->substate) {
5078                 case HCI_FALLING_ASLEEP_DISCONNECT:
5079                     log_info("HCI_STATE_FALLING_ASLEEP");
5080                     // close all open connections
5081                     connection =  (hci_connection_t *) hci_stack->connections;
5082                     if (connection){
5083 
5084                         // send disconnect
5085                         if (!hci_can_send_command_packet_now()) return;
5086 
5087                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5088                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5089 
5090                         // send disconnected event right away - causes higher layer connections to get closed, too.
5091                         hci_shutdown_connection(connection);
5092                         return;
5093                     }
5094 
5095                     if (hci_classic_supported()){
5096                         // disable page and inquiry scan
5097                         if (!hci_can_send_command_packet_now()) return;
5098 
5099                         log_info("HCI_STATE_HALTING, disabling inq scans");
5100                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5101 
5102                         // continue in next sub state
5103                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5104                         break;
5105                     }
5106 
5107                     /* fall through */
5108 
5109                 case HCI_FALLING_ASLEEP_COMPLETE:
5110                     log_info("HCI_STATE_HALTING, calling sleep");
5111                     // switch mode
5112                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5113                     hci_emit_state();
5114                     break;
5115 
5116                 default:
5117                     break;
5118             }
5119             break;
5120 
5121         default:
5122             break;
5123     }
5124 }
5125 
5126 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5127     // house-keeping
5128 
5129 #ifdef ENABLE_CLASSIC
5130     bd_addr_t addr;
5131     hci_connection_t * conn;
5132 #endif
5133 #ifdef ENABLE_LE_CENTRAL
5134     uint8_t initiator_filter_policy;
5135 #endif
5136 
5137     uint16_t opcode = little_endian_read_16(packet, 0);
5138     switch (opcode) {
5139         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5140             hci_stack->loopback_mode = packet[3];
5141             break;
5142 
5143 #ifdef ENABLE_CLASSIC
5144         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5145             reverse_bd_addr(&packet[3], addr);
5146             log_info("Create_connection to %s", bd_addr_to_str(addr));
5147 
5148             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5149             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5150                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5151                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5152             }
5153 
5154             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5155             if (!conn) {
5156                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5157                 if (!conn) {
5158                     // notify client that alloc failed
5159                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5160                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5161                 }
5162                 conn->state = SEND_CREATE_CONNECTION;
5163                 conn->role  = HCI_ROLE_MASTER;
5164             }
5165 
5166             conn->con_handle = HCI_CON_HANDLE_INVALID;
5167             conn->role = HCI_ROLE_INVALID;
5168 
5169             log_info("conn state %u", conn->state);
5170             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5171             switch (conn->state) {
5172                 // if connection active exists
5173                 case OPEN:
5174                     // and OPEN, emit connection complete command
5175                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5176                     // packet not sent to controller
5177                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5178                 case RECEIVED_DISCONNECTION_COMPLETE:
5179                     // create connection triggered in disconnect complete event, let's do it now
5180                     break;
5181                 case SEND_CREATE_CONNECTION:
5182                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5183                     break;
5184                 default:
5185                     // otherwise, just ignore as it is already in the open process
5186                     // packet not sent to controller
5187                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5188             }
5189             conn->state = SENT_CREATE_CONNECTION;
5190 
5191             // track outgoing connection
5192             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5193             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5194             break;
5195         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5196             if (hci_stack->link_key_db) {
5197                 reverse_bd_addr(&packet[3], addr);
5198                 hci_stack->link_key_db->delete_link_key(addr);
5199             }
5200             break;
5201 
5202 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5203         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5204             // setup_synchronous_connection? Voice setting at offset 22
5205             // TODO: compare to current setting if sco connection already active
5206             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5207             break;
5208         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5209             // accept_synchronus_connection? Voice setting at offset 18
5210             // TODO: compare to current setting if sco connection already active
5211             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5212             break;
5213 #endif
5214 #endif
5215 
5216 #ifdef ENABLE_BLE
5217         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5218             hci_stack->le_random_address_set = 1;
5219             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5220             break;
5221 #ifdef ENABLE_LE_PERIPHERAL
5222         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5223             hci_stack->le_advertisements_active = packet[3] != 0;
5224             break;
5225 #endif
5226 #ifdef ENABLE_LE_CENTRAL
5227         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5228             // white list used?
5229             initiator_filter_policy = packet[7];
5230             switch (initiator_filter_policy) {
5231                 case 0:
5232                     // whitelist not used
5233                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5234                     break;
5235                 case 1:
5236                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5237                     break;
5238                 default:
5239                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5240                     break;
5241             }
5242             // track outgoing connection
5243             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5244             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5245             break;
5246         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5247             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5248             break;
5249 #endif
5250 #endif
5251         default:
5252             break;
5253     }
5254 
5255     hci_stack->num_cmd_packets--;
5256 
5257     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5258     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5259     if (err != 0){
5260         return ERROR_CODE_HARDWARE_FAILURE;
5261     }
5262     return ERROR_CODE_SUCCESS;
5263 }
5264 
5265 // disconnect because of security block
5266 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5267     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5268     if (!connection) return;
5269     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5270 }
5271 
5272 
5273 // Configure Secure Simple Pairing
5274 
5275 #ifdef ENABLE_CLASSIC
5276 
5277 // enable will enable SSP during init
5278 void gap_ssp_set_enable(int enable){
5279     hci_stack->ssp_enable = enable;
5280 }
5281 
5282 static int hci_local_ssp_activated(void){
5283     return gap_ssp_supported() && hci_stack->ssp_enable;
5284 }
5285 
5286 // if set, BTstack will respond to io capability request using authentication requirement
5287 void gap_ssp_set_io_capability(int io_capability){
5288     hci_stack->ssp_io_capability = io_capability;
5289 }
5290 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5291     hci_stack->ssp_authentication_requirement = authentication_requirement;
5292 }
5293 
5294 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5295 void gap_ssp_set_auto_accept(int auto_accept){
5296     hci_stack->ssp_auto_accept = auto_accept;
5297 }
5298 
5299 void gap_secure_connections_enable(bool enable){
5300     hci_stack->secure_connections_enable = enable;
5301 }
5302 
5303 #endif
5304 
5305 // va_list part of hci_send_cmd
5306 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5307     if (!hci_can_send_command_packet_now()){
5308         log_error("hci_send_cmd called but cannot send packet now");
5309         return ERROR_CODE_COMMAND_DISALLOWED;
5310     }
5311 
5312     // for HCI INITIALIZATION
5313     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5314     hci_stack->last_cmd_opcode = cmd->opcode;
5315 
5316     hci_reserve_packet_buffer();
5317     uint8_t * packet = hci_stack->hci_packet_buffer;
5318     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5319     uint8_t status = hci_send_cmd_packet(packet, size);
5320 
5321     // release packet buffer on error or for synchronous transport implementations
5322     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5323         hci_release_packet_buffer();
5324         hci_emit_transport_packet_sent();
5325     }
5326 
5327     return status;
5328 }
5329 
5330 /**
5331  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5332  */
5333 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5334     va_list argptr;
5335     va_start(argptr, cmd);
5336     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5337     va_end(argptr);
5338     return status;
5339 }
5340 
5341 // Create various non-HCI events.
5342 // TODO: generalize, use table similar to hci_create_command
5343 
5344 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5345     // dump packet
5346     if (dump) {
5347         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5348     }
5349 
5350     // dispatch to all event handlers
5351     btstack_linked_list_iterator_t it;
5352     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5353     while (btstack_linked_list_iterator_has_next(&it)){
5354         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5355         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5356     }
5357 }
5358 
5359 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5360     if (!hci_stack->acl_packet_handler) return;
5361     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5362 }
5363 
5364 #ifdef ENABLE_CLASSIC
5365 static void hci_notify_if_sco_can_send_now(void){
5366     // notify SCO sender if waiting
5367     if (!hci_stack->sco_waiting_for_can_send_now) return;
5368     if (hci_can_send_sco_packet_now()){
5369         hci_stack->sco_waiting_for_can_send_now = 0;
5370         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5371         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5372         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5373     }
5374 }
5375 
5376 // parsing end emitting has been merged to reduce code size
5377 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5378     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5379 
5380     uint8_t * eir_data;
5381     ad_context_t context;
5382     const uint8_t * name;
5383     uint8_t         name_len;
5384 
5385     if (size < 3) return;
5386 
5387     int event_type = hci_event_packet_get_type(packet);
5388     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5389     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5390 
5391     switch (event_type){
5392         case HCI_EVENT_INQUIRY_RESULT:
5393         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5394             if (size != (3 + (num_responses * 14))) return;
5395             break;
5396         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5397             if (size != 257) return;
5398             if (num_responses != 1) return;
5399             break;
5400         default:
5401             return;
5402     }
5403 
5404     // event[1] is set at the end
5405     int i;
5406     for (i=0; i<num_responses;i++){
5407         memset(event, 0, sizeof(event));
5408         event[0] = GAP_EVENT_INQUIRY_RESULT;
5409         uint8_t event_size = 27;    // if name is not set by EIR
5410 
5411         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5412         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5413         (void)memcpy(&event[9],
5414                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5415                      3); // class of device
5416         (void)memcpy(&event[12],
5417                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5418                      2); // clock offset
5419 
5420         switch (event_type){
5421             case HCI_EVENT_INQUIRY_RESULT:
5422                 // 14,15,16,17 = 0, size 18
5423                 break;
5424             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5425                 event[14] = 1;
5426                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5427                 // 16,17 = 0, size 18
5428                 break;
5429             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5430                 event[14] = 1;
5431                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5432                 // EIR packets only contain a single inquiry response
5433                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5434                 name = NULL;
5435                 // Iterate over EIR data
5436                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5437                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5438                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5439                     const uint8_t * data = ad_iterator_get_data(&context);
5440                     // Prefer Complete Local Name over Shortened Local Name
5441                     switch (data_type){
5442                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5443                             if (name) continue;
5444                             /* fall through */
5445                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5446                             name = data;
5447                             name_len = data_size;
5448                             break;
5449                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5450                             if (data_size != 8) break;
5451                             event[16] = 1;
5452                             memcpy(&event[17], data, 8);
5453                             break;
5454                         default:
5455                             break;
5456                     }
5457                 }
5458                 if (name){
5459                     event[25] = 1;
5460                     // truncate name if needed
5461                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5462                     event[26] = len;
5463                     (void)memcpy(&event[27], name, len);
5464                     event_size += len;
5465                 }
5466                 break;
5467             default:
5468                 return;
5469         }
5470         event[1] = event_size - 2;
5471         hci_emit_event(event, event_size, 1);
5472     }
5473 }
5474 #endif
5475 
5476 void hci_emit_state(void){
5477     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5478     uint8_t event[3];
5479     event[0] = BTSTACK_EVENT_STATE;
5480     event[1] = sizeof(event) - 2u;
5481     event[2] = hci_stack->state;
5482     hci_emit_event(event, sizeof(event), 1);
5483 }
5484 
5485 #ifdef ENABLE_CLASSIC
5486 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5487     uint8_t event[13];
5488     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5489     event[1] = sizeof(event) - 2;
5490     event[2] = status;
5491     little_endian_store_16(event, 3, con_handle);
5492     reverse_bd_addr(address, &event[5]);
5493     event[11] = 1; // ACL connection
5494     event[12] = 0; // encryption disabled
5495     hci_emit_event(event, sizeof(event), 1);
5496 }
5497 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5498     if (disable_l2cap_timeouts) return;
5499     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5500     uint8_t event[4];
5501     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5502     event[1] = sizeof(event) - 2;
5503     little_endian_store_16(event, 2, conn->con_handle);
5504     hci_emit_event(event, sizeof(event), 1);
5505 }
5506 #endif
5507 
5508 #ifdef ENABLE_BLE
5509 #ifdef ENABLE_LE_CENTRAL
5510 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){
5511     uint8_t event[21];
5512     event[0] = HCI_EVENT_LE_META;
5513     event[1] = sizeof(event) - 2u;
5514     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5515     event[3] = status;
5516     little_endian_store_16(event, 4, con_handle);
5517     event[6] = 0; // TODO: role
5518     event[7] = address_type;
5519     reverse_bd_addr(address, &event[8]);
5520     little_endian_store_16(event, 14, 0); // interval
5521     little_endian_store_16(event, 16, 0); // latency
5522     little_endian_store_16(event, 18, 0); // supervision timeout
5523     event[20] = 0; // master clock accuracy
5524     hci_emit_event(event, sizeof(event), 1);
5525 }
5526 #endif
5527 #endif
5528 
5529 static void hci_emit_transport_packet_sent(void){
5530     // notify upper stack that it might be possible to send again
5531     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5532     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5533 }
5534 
5535 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5536     uint8_t event[6];
5537     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5538     event[1] = sizeof(event) - 2u;
5539     event[2] = 0; // status = OK
5540     little_endian_store_16(event, 3, con_handle);
5541     event[5] = reason;
5542     hci_emit_event(event, sizeof(event), 1);
5543 }
5544 
5545 static void hci_emit_nr_connections_changed(void){
5546     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5547     uint8_t event[3];
5548     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5549     event[1] = sizeof(event) - 2u;
5550     event[2] = nr_hci_connections();
5551     hci_emit_event(event, sizeof(event), 1);
5552 }
5553 
5554 static void hci_emit_hci_open_failed(void){
5555     log_info("BTSTACK_EVENT_POWERON_FAILED");
5556     uint8_t event[2];
5557     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5558     event[1] = sizeof(event) - 2u;
5559     hci_emit_event(event, sizeof(event), 1);
5560 }
5561 
5562 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5563     log_info("hci_emit_dedicated_bonding_result %u ", status);
5564     uint8_t event[9];
5565     int pos = 0;
5566     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5567     event[pos++] = sizeof(event) - 2u;
5568     event[pos++] = status;
5569     reverse_bd_addr(address, &event[pos]);
5570     hci_emit_event(event, sizeof(event), 1);
5571 }
5572 
5573 
5574 #ifdef ENABLE_CLASSIC
5575 
5576 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5577     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5578     uint8_t event[5];
5579     int pos = 0;
5580     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5581     event[pos++] = sizeof(event) - 2;
5582     little_endian_store_16(event, 2, con_handle);
5583     pos += 2;
5584     event[pos++] = level;
5585     hci_emit_event(event, sizeof(event), 1);
5586 }
5587 
5588 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5589     if (!connection) return LEVEL_0;
5590     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5591     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5592     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5593     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5594     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5595     // LEVEL 4 always requires 128 bit encrytion key size
5596     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5597         security_level = LEVEL_3;
5598     }
5599     return security_level;
5600 }
5601 
5602 static void hci_emit_discoverable_enabled(uint8_t enabled){
5603     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5604     uint8_t event[3];
5605     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5606     event[1] = sizeof(event) - 2;
5607     event[2] = enabled;
5608     hci_emit_event(event, sizeof(event), 1);
5609 }
5610 
5611 // query if remote side supports eSCO
5612 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5613     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5614     if (!connection) return false;
5615     return (connection->remote_supported_features[0] & 1) != 0;
5616 }
5617 
5618 static bool hci_ssp_supported(hci_connection_t * connection){
5619     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5620     return (connection->bonding_flags & mask) == mask;
5621 }
5622 
5623 // query if remote side supports SSP
5624 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5625     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5626     if (!connection) return false;
5627     return hci_ssp_supported(connection) ? 1 : 0;
5628 }
5629 
5630 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5631     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5632 }
5633 
5634 // GAP API
5635 /**
5636  * @bbrief enable/disable bonding. default is enabled
5637  * @praram enabled
5638  */
5639 void gap_set_bondable_mode(int enable){
5640     hci_stack->bondable = enable ? 1 : 0;
5641 }
5642 /**
5643  * @brief Get bondable mode.
5644  * @return 1 if bondable
5645  */
5646 int gap_get_bondable_mode(void){
5647     return hci_stack->bondable;
5648 }
5649 
5650 /**
5651  * @brief map link keys to security levels
5652  */
5653 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5654     switch (link_key_type){
5655         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5656             return LEVEL_4;
5657         case COMBINATION_KEY:
5658         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5659             return LEVEL_3;
5660         default:
5661             return LEVEL_2;
5662     }
5663 }
5664 
5665 /**
5666  * @brief map link keys to secure connection yes/no
5667  */
5668 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5669     switch (link_key_type){
5670         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5671         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5672             return 1;
5673         default:
5674             return 0;
5675     }
5676 }
5677 
5678 /**
5679  * @brief map link keys to authenticated
5680  */
5681 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5682     switch (link_key_type){
5683         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5684         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5685             return 1;
5686         default:
5687             return 0;
5688     }
5689 }
5690 
5691 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5692     log_info("gap_mitm_protection_required_for_security_level %u", level);
5693     return level > LEVEL_2;
5694 }
5695 
5696 /**
5697  * @brief get current security level
5698  */
5699 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5700     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5701     if (!connection) return LEVEL_0;
5702     return gap_security_level_for_connection(connection);
5703 }
5704 
5705 /**
5706  * @brief request connection to device to
5707  * @result GAP_AUTHENTICATION_RESULT
5708  */
5709 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5710     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5711     if (!connection){
5712         hci_emit_security_level(con_handle, LEVEL_0);
5713         return;
5714     }
5715 
5716     btstack_assert(hci_is_le_connection(connection) == false);
5717 
5718     // 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)
5719     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5720     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5721         requested_level = LEVEL_4;
5722     }
5723 
5724     gap_security_level_t current_level = gap_security_level(con_handle);
5725     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5726         requested_level, connection->requested_security_level, current_level);
5727 
5728     // authentication active if authentication request was sent or planned level > 0
5729     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5730     if (authentication_active){
5731         // authentication already active
5732         if (connection->requested_security_level < requested_level){
5733             // increase requested level as new level is higher
5734             // TODO: handle re-authentication when done
5735             connection->requested_security_level = requested_level;
5736         }
5737     } else {
5738         // no request active, notify if security sufficient
5739         if (requested_level <= current_level){
5740             hci_emit_security_level(con_handle, current_level);
5741             return;
5742         }
5743 
5744         // store request
5745         connection->requested_security_level = requested_level;
5746 
5747         // start to authenticate connection
5748         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5749         hci_run();
5750     }
5751 }
5752 
5753 /**
5754  * @brief start dedicated bonding with device. disconnect after bonding
5755  * @param device
5756  * @param request MITM protection
5757  * @result GAP_DEDICATED_BONDING_COMPLETE
5758  */
5759 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5760 
5761     // create connection state machine
5762     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5763 
5764     if (!connection){
5765         return BTSTACK_MEMORY_ALLOC_FAILED;
5766     }
5767 
5768     // delete linkn key
5769     gap_drop_link_key_for_bd_addr(device);
5770 
5771     // configure LEVEL_2/3, dedicated bonding
5772     connection->state = SEND_CREATE_CONNECTION;
5773     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5774     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5775     connection->bonding_flags = BONDING_DEDICATED;
5776 
5777     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5778 
5779     // handle: connnection failure (connection complete != ok)
5780     // handle: authentication failure
5781     // handle: disconnect on done
5782 
5783     hci_run();
5784 
5785     return 0;
5786 }
5787 
5788 void gap_set_local_name(const char * local_name){
5789     hci_stack->local_name = local_name;
5790     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5791     // also update EIR if not set by user
5792     if (hci_stack->eir_data == NULL){
5793         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5794     }
5795     hci_run();
5796 }
5797 #endif
5798 
5799 
5800 #ifdef ENABLE_BLE
5801 
5802 #ifdef ENABLE_LE_CENTRAL
5803 void gap_start_scan(void){
5804     hci_stack->le_scanning_enabled = true;
5805     hci_run();
5806 }
5807 
5808 void gap_stop_scan(void){
5809     hci_stack->le_scanning_enabled = false;
5810     hci_run();
5811 }
5812 
5813 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5814     hci_stack->le_scan_type          = scan_type;
5815     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5816     hci_stack->le_scan_interval      = scan_interval;
5817     hci_stack->le_scan_window        = scan_window;
5818     hci_stack->le_scanning_param_update = true;
5819     hci_run();
5820 }
5821 
5822 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5823     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5824 }
5825 
5826 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5827     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5828     if (!conn){
5829         // disallow if le connection is already outgoing
5830         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5831             log_error("le connection already active");
5832             return ERROR_CODE_COMMAND_DISALLOWED;
5833         }
5834 
5835         log_info("gap_connect: no connection exists yet, creating context");
5836         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5837         if (!conn){
5838             // notify client that alloc failed
5839             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5840             log_info("gap_connect: failed to alloc hci_connection_t");
5841             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5842         }
5843 
5844         // set le connecting state
5845         if (hci_is_le_connection_type(addr_type)){
5846             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5847         }
5848 
5849         conn->state = SEND_CREATE_CONNECTION;
5850         log_info("gap_connect: send create connection next");
5851         hci_run();
5852         return ERROR_CODE_SUCCESS;
5853     }
5854 
5855     if (!hci_is_le_connection(conn) ||
5856         (conn->state == SEND_CREATE_CONNECTION) ||
5857         (conn->state == SENT_CREATE_CONNECTION)) {
5858         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5859         log_error("gap_connect: classic connection or connect is already being created");
5860         return GATT_CLIENT_IN_WRONG_STATE;
5861     }
5862 
5863     // check if connection was just disconnected
5864     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5865         log_info("gap_connect: send create connection (again)");
5866         conn->state = SEND_CREATE_CONNECTION;
5867         hci_run();
5868         return ERROR_CODE_SUCCESS;
5869     }
5870 
5871     log_info("gap_connect: context exists with state %u", conn->state);
5872     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5873     hci_run();
5874     return ERROR_CODE_SUCCESS;
5875 }
5876 
5877 // @assumption: only a single outgoing LE Connection exists
5878 static hci_connection_t * gap_get_outgoing_connection(void){
5879     btstack_linked_item_t *it;
5880     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5881         hci_connection_t * conn = (hci_connection_t *) it;
5882         if (!hci_is_le_connection(conn)) continue;
5883         switch (conn->state){
5884             case SEND_CREATE_CONNECTION:
5885             case SENT_CREATE_CONNECTION:
5886             case SENT_CANCEL_CONNECTION:
5887                 return conn;
5888             default:
5889                 break;
5890         };
5891     }
5892     return NULL;
5893 }
5894 
5895 uint8_t gap_connect_cancel(void){
5896     hci_connection_t * conn = gap_get_outgoing_connection();
5897     if (!conn) return 0;
5898     switch (conn->state){
5899         case SEND_CREATE_CONNECTION:
5900             // skip sending create connection and emit event instead
5901             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5902             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5903             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5904             btstack_memory_hci_connection_free( conn );
5905             break;
5906         case SENT_CREATE_CONNECTION:
5907             // request to send cancel connection
5908             conn->state = SEND_CANCEL_CONNECTION;
5909             hci_run();
5910             break;
5911         default:
5912             break;
5913     }
5914     return 0;
5915 }
5916 #endif
5917 
5918 #ifdef ENABLE_LE_CENTRAL
5919 /**
5920  * @brief Set connection parameters for outgoing connections
5921  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5922  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5923  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5924  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5925  * @param conn_latency, default: 4
5926  * @param supervision_timeout (unit: 10ms), default: 720 ms
5927  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5928  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5929  */
5930 
5931 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5932     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5933     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5934     hci_stack->le_connection_scan_interval = conn_scan_interval;
5935     hci_stack->le_connection_scan_window = conn_scan_window;
5936     hci_stack->le_connection_interval_min = conn_interval_min;
5937     hci_stack->le_connection_interval_max = conn_interval_max;
5938     hci_stack->le_connection_latency = conn_latency;
5939     hci_stack->le_supervision_timeout = supervision_timeout;
5940     hci_stack->le_minimum_ce_length = min_ce_length;
5941     hci_stack->le_maximum_ce_length = max_ce_length;
5942 }
5943 #endif
5944 
5945 /**
5946  * @brief Updates the connection parameters for a given LE connection
5947  * @param handle
5948  * @param conn_interval_min (unit: 1.25ms)
5949  * @param conn_interval_max (unit: 1.25ms)
5950  * @param conn_latency
5951  * @param supervision_timeout (unit: 10ms)
5952  * @returns 0 if ok
5953  */
5954 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5955     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5956     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5957     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5958     connection->le_conn_interval_min = conn_interval_min;
5959     connection->le_conn_interval_max = conn_interval_max;
5960     connection->le_conn_latency = conn_latency;
5961     connection->le_supervision_timeout = supervision_timeout;
5962     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5963     hci_run();
5964     return 0;
5965 }
5966 
5967 /**
5968  * @brief Request an update of the connection parameter for a given LE connection
5969  * @param handle
5970  * @param conn_interval_min (unit: 1.25ms)
5971  * @param conn_interval_max (unit: 1.25ms)
5972  * @param conn_latency
5973  * @param supervision_timeout (unit: 10ms)
5974  * @returns 0 if ok
5975  */
5976 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5977     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5978     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5979     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5980     connection->le_conn_interval_min = conn_interval_min;
5981     connection->le_conn_interval_max = conn_interval_max;
5982     connection->le_conn_latency = conn_latency;
5983     connection->le_supervision_timeout = supervision_timeout;
5984     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5985     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5986     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5987     return 0;
5988 }
5989 
5990 #ifdef ENABLE_LE_PERIPHERAL
5991 
5992 /**
5993  * @brief Set Advertisement Data
5994  * @param advertising_data_length
5995  * @param advertising_data (max 31 octets)
5996  * @note data is not copied, pointer has to stay valid
5997  */
5998 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5999     hci_stack->le_advertisements_data_len = advertising_data_length;
6000     hci_stack->le_advertisements_data = advertising_data;
6001     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6002     hci_run();
6003 }
6004 
6005 /**
6006  * @brief Set Scan Response Data
6007  * @param advertising_data_length
6008  * @param advertising_data (max 31 octets)
6009  * @note data is not copied, pointer has to stay valid
6010  */
6011 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6012     hci_stack->le_scan_response_data_len = scan_response_data_length;
6013     hci_stack->le_scan_response_data = scan_response_data;
6014     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6015     hci_run();
6016 }
6017 
6018 /**
6019  * @brief Set Advertisement Parameters
6020  * @param adv_int_min
6021  * @param adv_int_max
6022  * @param adv_type
6023  * @param direct_address_type
6024  * @param direct_address
6025  * @param channel_map
6026  * @param filter_policy
6027  *
6028  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6029  */
6030  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6031     uint8_t direct_address_typ, bd_addr_t direct_address,
6032     uint8_t channel_map, uint8_t filter_policy) {
6033 
6034     hci_stack->le_advertisements_interval_min = adv_int_min;
6035     hci_stack->le_advertisements_interval_max = adv_int_max;
6036     hci_stack->le_advertisements_type = adv_type;
6037     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6038     hci_stack->le_advertisements_channel_map = channel_map;
6039     hci_stack->le_advertisements_filter_policy = filter_policy;
6040     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6041                  6);
6042 
6043     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6044     hci_run();
6045  }
6046 
6047 /**
6048  * @brief Enable/Disable Advertisements
6049  * @param enabled
6050  */
6051 void gap_advertisements_enable(int enabled){
6052     hci_stack->le_advertisements_enabled = enabled != 0;
6053     hci_update_advertisements_enabled_for_current_roles();
6054     hci_run();
6055 }
6056 
6057 #endif
6058 
6059 void hci_le_set_own_address_type(uint8_t own_address_type){
6060     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6061     if (own_address_type == hci_stack->le_own_addr_type) return;
6062     hci_stack->le_own_addr_type = own_address_type;
6063 
6064 #ifdef ENABLE_LE_PERIPHERAL
6065     // update advertisement parameters, too
6066     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6067     hci_run();
6068 #endif
6069 #ifdef ENABLE_LE_CENTRAL
6070     // note: we don't update scan parameters or modify ongoing connection attempts
6071 #endif
6072 }
6073 
6074 #endif
6075 
6076 uint8_t gap_disconnect(hci_con_handle_t handle){
6077     hci_connection_t * conn = hci_connection_for_handle(handle);
6078     if (!conn){
6079         hci_emit_disconnection_complete(handle, 0);
6080         return 0;
6081     }
6082     // ignore if already disconnected
6083     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6084         return 0;
6085     }
6086     conn->state = SEND_DISCONNECT;
6087     hci_run();
6088     return 0;
6089 }
6090 
6091 int gap_read_rssi(hci_con_handle_t con_handle){
6092     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6093     if (hci_connection == NULL) return 0;
6094     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6095     hci_run();
6096     return 1;
6097 }
6098 
6099 /**
6100  * @brief Get connection type
6101  * @param con_handle
6102  * @result connection_type
6103  */
6104 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6105     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6106     if (!conn) return GAP_CONNECTION_INVALID;
6107     switch (conn->address_type){
6108         case BD_ADDR_TYPE_LE_PUBLIC:
6109         case BD_ADDR_TYPE_LE_RANDOM:
6110             return GAP_CONNECTION_LE;
6111         case BD_ADDR_TYPE_SCO:
6112             return GAP_CONNECTION_SCO;
6113         case BD_ADDR_TYPE_ACL:
6114             return GAP_CONNECTION_ACL;
6115         default:
6116             return GAP_CONNECTION_INVALID;
6117     }
6118 }
6119 
6120 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6121     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6122     if (!conn) return HCI_ROLE_INVALID;
6123     return (hci_role_t) conn->role;
6124 }
6125 
6126 
6127 #ifdef ENABLE_CLASSIC
6128 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6129     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6130     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6131     conn->request_role = role;
6132     hci_run();
6133     return ERROR_CODE_SUCCESS;
6134 }
6135 #endif
6136 
6137 #ifdef ENABLE_BLE
6138 
6139 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){
6140     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6141     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6142 
6143     conn->le_phy_update_all_phys    = all_phys;
6144     conn->le_phy_update_tx_phys     = tx_phys;
6145     conn->le_phy_update_rx_phys     = rx_phys;
6146     conn->le_phy_update_phy_options = phy_options;
6147 
6148     hci_run();
6149 
6150     return 0;
6151 }
6152 
6153 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6154     // check if already in list
6155     btstack_linked_list_iterator_t it;
6156     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6157     while (btstack_linked_list_iterator_has_next(&it)) {
6158         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6159         if (entry->address_type != address_type) {
6160             continue;
6161         }
6162         if (memcmp(entry->address, address, 6) != 0) {
6163             continue;
6164         }
6165 		// disallow if already scheduled to add
6166 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6167 			return ERROR_CODE_COMMAND_DISALLOWED;
6168 		}
6169 		// still on controller, but scheduled to remove -> re-add
6170 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6171 		return ERROR_CODE_SUCCESS;
6172     }
6173     // alloc and add to list
6174     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6175     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6176     entry->address_type = address_type;
6177     (void)memcpy(entry->address, address, 6);
6178     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6179     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6180     return ERROR_CODE_SUCCESS;
6181 }
6182 
6183 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6184     btstack_linked_list_iterator_t it;
6185     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6186     while (btstack_linked_list_iterator_has_next(&it)){
6187         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6188         if (entry->address_type != address_type) {
6189             continue;
6190         }
6191         if (memcmp(entry->address, address, 6) != 0) {
6192             continue;
6193         }
6194         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6195             // remove from controller if already present
6196             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6197         }  else {
6198             // directly remove entry from whitelist
6199             btstack_linked_list_iterator_remove(&it);
6200             btstack_memory_whitelist_entry_free(entry);
6201         }
6202         return ERROR_CODE_SUCCESS;
6203     }
6204     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6205 }
6206 
6207 static void hci_whitelist_clear(void){
6208     btstack_linked_list_iterator_t it;
6209     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6210     while (btstack_linked_list_iterator_has_next(&it)){
6211         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6212         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6213             // remove from controller if already present
6214             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6215             continue;
6216         }
6217         // directly remove entry from whitelist
6218         btstack_linked_list_iterator_remove(&it);
6219         btstack_memory_whitelist_entry_free(entry);
6220     }
6221 }
6222 
6223 /**
6224  * @brief Clear Whitelist
6225  * @returns 0 if ok
6226  */
6227 uint8_t gap_whitelist_clear(void){
6228     hci_whitelist_clear();
6229     hci_run();
6230     return ERROR_CODE_SUCCESS;
6231 }
6232 
6233 /**
6234  * @brief Add Device to Whitelist
6235  * @param address_typ
6236  * @param address
6237  * @returns 0 if ok
6238  */
6239 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6240     uint8_t status = hci_whitelist_add(address_type, address);
6241     if (status){
6242         return status;
6243     }
6244     hci_run();
6245     return ERROR_CODE_SUCCESS;
6246 }
6247 
6248 /**
6249  * @brief Remove Device from Whitelist
6250  * @param address_typ
6251  * @param address
6252  * @returns 0 if ok
6253  */
6254 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6255     uint8_t status = hci_whitelist_remove(address_type, address);
6256     if (status){
6257         return status;
6258     }
6259     hci_run();
6260     return ERROR_CODE_SUCCESS;
6261 }
6262 
6263 #ifdef ENABLE_LE_CENTRAL
6264 /**
6265  *  @brief Connect with Whitelist
6266  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6267  *  @returns - if ok
6268  */
6269 uint8_t gap_connect_with_whitelist(void){
6270     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6271         return ERROR_CODE_COMMAND_DISALLOWED;
6272     }
6273     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6274     hci_run();
6275     return ERROR_CODE_SUCCESS;
6276 }
6277 
6278 /**
6279  * @brief Auto Connection Establishment - Start Connecting to device
6280  * @param address_typ
6281  * @param address
6282  * @returns 0 if ok
6283  */
6284 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6285     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6286         return ERROR_CODE_COMMAND_DISALLOWED;
6287     }
6288 
6289     uint8_t status = hci_whitelist_add(address_type, address);
6290     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6291         return status;
6292     }
6293 
6294     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6295 
6296     hci_run();
6297     return ERROR_CODE_SUCCESS;
6298 }
6299 
6300 /**
6301  * @brief Auto Connection Establishment - Stop Connecting to device
6302  * @param address_typ
6303  * @param address
6304  * @returns 0 if ok
6305  */
6306 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6307     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6308         return ERROR_CODE_COMMAND_DISALLOWED;
6309     }
6310 
6311     hci_whitelist_remove(address_type, address);
6312     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6313         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6314     }
6315     hci_run();
6316     return 0;
6317 }
6318 
6319 /**
6320  * @brief Auto Connection Establishment - Stop everything
6321  * @note  Convenience function to stop all active auto connection attempts
6322  */
6323 uint8_t gap_auto_connection_stop_all(void){
6324     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6325         return ERROR_CODE_COMMAND_DISALLOWED;
6326     }
6327     hci_whitelist_clear();
6328     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6329     hci_run();
6330     return ERROR_CODE_SUCCESS;
6331 }
6332 
6333 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6334     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6335     if (!conn) return 0;
6336     return conn->le_connection_interval;
6337 }
6338 #endif
6339 #endif
6340 
6341 #ifdef ENABLE_CLASSIC
6342 /**
6343  * @brief Set Extended Inquiry Response data
6344  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6345  * @note has to be done before stack starts up
6346  */
6347 void gap_set_extended_inquiry_response(const uint8_t * data){
6348     hci_stack->eir_data = data;
6349     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6350     hci_run();
6351 }
6352 
6353 /**
6354  * @brief Start GAP Classic Inquiry
6355  * @param duration in 1.28s units
6356  * @return 0 if ok
6357  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6358  */
6359 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6360     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6361     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6362     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6363         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6364     }
6365     hci_stack->inquiry_state = duration_in_1280ms_units;
6366     hci_run();
6367     return 0;
6368 }
6369 
6370 /**
6371  * @brief Stop GAP Classic Inquiry
6372  * @returns 0 if ok
6373  */
6374 int gap_inquiry_stop(void){
6375     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6376         // emit inquiry complete event, before it even started
6377         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6378         hci_emit_event(event, sizeof(event), 1);
6379         return 0;
6380     }
6381     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6382     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6383     hci_run();
6384     return 0;
6385 }
6386 
6387 void gap_inquiry_set_lap(uint32_t lap){
6388     hci_stack->inquiry_lap = lap;
6389 }
6390 
6391 
6392 /**
6393  * @brief Remote Name Request
6394  * @param addr
6395  * @param page_scan_repetition_mode
6396  * @param clock_offset only used when bit 15 is set
6397  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6398  */
6399 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6400     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6401     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6402     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6403     hci_stack->remote_name_clock_offset = clock_offset;
6404     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6405     hci_run();
6406     return 0;
6407 }
6408 
6409 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6410     hci_stack->gap_pairing_state = state;
6411     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6412     hci_run();
6413     return 0;
6414 }
6415 
6416 /**
6417  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6418  * @param addr
6419  * @param pin_data
6420  * @param pin_len
6421  * @return 0 if ok
6422  */
6423 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6424     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6425     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6426     hci_stack->gap_pairing_pin_len = pin_len;
6427     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6428 }
6429 
6430 /**
6431  * @brief Legacy Pairing Pin Code Response
6432  * @param addr
6433  * @param pin
6434  * @return 0 if ok
6435  */
6436 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6437     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6438 }
6439 
6440 /**
6441  * @brief Abort Legacy Pairing
6442  * @param addr
6443  * @param pin
6444  * @return 0 if ok
6445  */
6446 int gap_pin_code_negative(bd_addr_t addr){
6447     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6448     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6449 }
6450 
6451 /**
6452  * @brief SSP Passkey Response
6453  * @param addr
6454  * @param passkey
6455  * @return 0 if ok
6456  */
6457 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6458     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6459     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6460     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6461 }
6462 
6463 /**
6464  * @brief Abort SSP Passkey Entry/Pairing
6465  * @param addr
6466  * @param pin
6467  * @return 0 if ok
6468  */
6469 int gap_ssp_passkey_negative(const bd_addr_t addr){
6470     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6471     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6472 }
6473 
6474 /**
6475  * @brief Accept SSP Numeric Comparison
6476  * @param addr
6477  * @param passkey
6478  * @return 0 if ok
6479  */
6480 int gap_ssp_confirmation_response(const bd_addr_t addr){
6481     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6482     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6483 }
6484 
6485 /**
6486  * @brief Abort SSP Numeric Comparison/Pairing
6487  * @param addr
6488  * @param pin
6489  * @return 0 if ok
6490  */
6491 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6492     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6493     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6494 }
6495 
6496 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6497 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6498     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6499     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6500     connectionSetAuthenticationFlags(conn, flag);
6501     hci_run();
6502     return ERROR_CODE_SUCCESS;
6503 }
6504 #endif
6505 
6506 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6507 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6508     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6509 }
6510 
6511 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6512     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6513 }
6514 #endif
6515 
6516 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6517 /**
6518  * @brief Report Remote OOB Data
6519  * @param bd_addr
6520  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6521  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6522  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6523  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6524  */
6525 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){
6526     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6527     if (connection == NULL) {
6528         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6529     }
6530     connection->classic_oob_c_192 = c_192;
6531     connection->classic_oob_r_192 = r_192;
6532 
6533     // ignore P-256 if not supported by us
6534     if (hci_stack->secure_connections_active){
6535         connection->classic_oob_c_256 = c_256;
6536         connection->classic_oob_r_256 = r_256;
6537     }
6538 
6539     return ERROR_CODE_SUCCESS;
6540 }
6541 /**
6542  * @brief Generate new OOB data
6543  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6544  */
6545 void gap_ssp_generate_oob_data(void){
6546     hci_stack->classic_read_local_oob_data = true;
6547     hci_run();
6548 }
6549 
6550 #endif
6551 
6552 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6553 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6554     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6555     if (connection == NULL) {
6556         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6557     }
6558 
6559     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6560     connection->link_key_type = type;
6561 
6562     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6563 }
6564 
6565 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6566 /**
6567  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6568  * @param inquiry_mode see bluetooth_defines.h
6569  */
6570 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6571     hci_stack->inquiry_mode = inquiry_mode;
6572 }
6573 
6574 /**
6575  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6576  */
6577 void hci_set_sco_voice_setting(uint16_t voice_setting){
6578     hci_stack->sco_voice_setting = voice_setting;
6579 }
6580 
6581 /**
6582  * @brief Get SCO Voice Setting
6583  * @return current voice setting
6584  */
6585 uint16_t hci_get_sco_voice_setting(void){
6586     return hci_stack->sco_voice_setting;
6587 }
6588 
6589 static int hci_have_usb_transport(void){
6590     if (!hci_stack->hci_transport) return 0;
6591     const char * transport_name = hci_stack->hci_transport->name;
6592     if (!transport_name) return 0;
6593     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6594 }
6595 
6596 /** @brief Get SCO packet length for current SCO Voice setting
6597  *  @note  Using SCO packets of the exact length is required for USB transfer
6598  *  @return Length of SCO packets in bytes (not audio frames)
6599  */
6600 uint16_t hci_get_sco_packet_length(void){
6601     uint16_t sco_packet_length = 0;
6602 
6603 #ifdef ENABLE_SCO_OVER_HCI
6604     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6605     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6606 
6607     if (hci_have_usb_transport()){
6608         // see Core Spec for H2 USB Transfer.
6609         // 3 byte SCO header + 24 bytes per connection
6610         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6611         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6612     } else {
6613         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6614         sco_packet_length = 3 + 60 * multiplier;
6615         // assert that it still fits inside an SCO buffer
6616         if (sco_packet_length > hci_stack->sco_data_packet_length){
6617             sco_packet_length = 3 + 60;
6618         }
6619     }
6620 #endif
6621 
6622 #ifdef HAVE_SCO_TRANSPORT
6623     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6624     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6625     sco_packet_length = 3 + 60 * multiplier;
6626 #endif
6627     return sco_packet_length;
6628 }
6629 
6630 /**
6631 * @brief Sets the master/slave policy
6632 * @param policy (0: attempt to become master, 1: let connecting device decide)
6633 */
6634 void hci_set_master_slave_policy(uint8_t policy){
6635     hci_stack->master_slave_policy = policy;
6636 }
6637 
6638 #endif
6639 
6640 HCI_STATE hci_get_state(void){
6641     return hci_stack->state;
6642 }
6643 
6644 #ifdef ENABLE_CLASSIC
6645 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6646     hci_stack->gap_classic_accept_callback = accept_callback;
6647 }
6648 #endif
6649 
6650 /**
6651  * @brief Set callback for Bluetooth Hardware Error
6652  */
6653 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6654     hci_stack->hardware_error_callback = fn;
6655 }
6656 
6657 void hci_disconnect_all(void){
6658     btstack_linked_list_iterator_t it;
6659     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6660     while (btstack_linked_list_iterator_has_next(&it)){
6661         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6662         if (con->state == SENT_DISCONNECT) continue;
6663         con->state = SEND_DISCONNECT;
6664     }
6665     hci_run();
6666 }
6667 
6668 uint16_t hci_get_manufacturer(void){
6669     return hci_stack->manufacturer;
6670 }
6671 
6672 #ifdef ENABLE_BLE
6673 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6674     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6675     if (!hci_con) return NULL;
6676     return &hci_con->sm_connection;
6677 }
6678 
6679 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6680 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6681 #endif
6682 
6683 int gap_encryption_key_size(hci_con_handle_t con_handle){
6684     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6685     if (hci_connection == NULL) return 0;
6686     if (hci_is_le_connection(hci_connection)){
6687 #ifdef ENABLE_BLE
6688         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6689         if (sm_conn->sm_connection_encrypted) {
6690             return sm_conn->sm_actual_encryption_key_size;
6691         }
6692 #endif
6693     } else {
6694 #ifdef ENABLE_CLASSIC
6695         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6696             return hci_connection->encryption_key_size;
6697         }
6698 #endif
6699     }
6700     return 0;
6701 }
6702 
6703 int gap_authenticated(hci_con_handle_t con_handle){
6704     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6705     if (hci_connection == NULL) return 0;
6706 
6707     switch (hci_connection->address_type){
6708 #ifdef ENABLE_BLE
6709         case BD_ADDR_TYPE_LE_PUBLIC:
6710         case BD_ADDR_TYPE_LE_RANDOM:
6711             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6712             return hci_connection->sm_connection.sm_connection_authenticated;
6713 #endif
6714 #ifdef ENABLE_CLASSIC
6715         case BD_ADDR_TYPE_SCO:
6716         case BD_ADDR_TYPE_ACL:
6717             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6718 #endif
6719         default:
6720             return 0;
6721     }
6722 }
6723 
6724 int gap_secure_connection(hci_con_handle_t con_handle){
6725     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6726     if (hci_connection == NULL) return 0;
6727 
6728     switch (hci_connection->address_type){
6729 #ifdef ENABLE_BLE
6730         case BD_ADDR_TYPE_LE_PUBLIC:
6731         case BD_ADDR_TYPE_LE_RANDOM:
6732             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6733             return hci_connection->sm_connection.sm_connection_sc;
6734 #endif
6735 #ifdef ENABLE_CLASSIC
6736         case BD_ADDR_TYPE_SCO:
6737         case BD_ADDR_TYPE_ACL:
6738             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6739 #endif
6740         default:
6741             return 0;
6742     }
6743 }
6744 
6745 bool gap_bonded(hci_con_handle_t con_handle){
6746 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6747 	if (hci_connection == NULL) return 0;
6748 
6749 #ifdef ENABLE_CLASSIC
6750 	link_key_t link_key;
6751 	link_key_type_t link_key_type;
6752 #endif
6753 	switch (hci_connection->address_type){
6754 #ifdef ENABLE_BLE
6755 		case BD_ADDR_TYPE_LE_PUBLIC:
6756 		case BD_ADDR_TYPE_LE_RANDOM:
6757 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6758 #endif
6759 #ifdef ENABLE_CLASSIC
6760 		case BD_ADDR_TYPE_SCO:
6761 		case BD_ADDR_TYPE_ACL:
6762 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6763 #endif
6764 		default:
6765 			return false;
6766 	}
6767 }
6768 
6769 #ifdef ENABLE_BLE
6770 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6771     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6772     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6773     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6774     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6775     return sm_conn->sm_connection_authorization_state;
6776 }
6777 #endif
6778 
6779 #ifdef ENABLE_CLASSIC
6780 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){
6781     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6782     if (!conn) return GAP_CONNECTION_INVALID;
6783     conn->sniff_min_interval = sniff_min_interval;
6784     conn->sniff_max_interval = sniff_max_interval;
6785     conn->sniff_attempt = sniff_attempt;
6786     conn->sniff_timeout = sniff_timeout;
6787     hci_run();
6788     return 0;
6789 }
6790 
6791 /**
6792  * @brief Exit Sniff mode
6793  * @param con_handle
6794  @ @return 0 if ok
6795  */
6796 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6797     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6798     if (!conn) return GAP_CONNECTION_INVALID;
6799     conn->sniff_min_interval = 0xffff;
6800     hci_run();
6801     return 0;
6802 }
6803 
6804 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){
6805     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6806     if (!conn) return GAP_CONNECTION_INVALID;
6807     conn->sniff_subrating_max_latency = max_latency;
6808     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6809     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6810     hci_run();
6811     return ERROR_CODE_SUCCESS;
6812 }
6813 
6814 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){
6815     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6816     if (!conn) return GAP_CONNECTION_INVALID;
6817     conn->qos_service_type = service_type;
6818     conn->qos_token_rate = token_rate;
6819     conn->qos_peak_bandwidth = peak_bandwidth;
6820     conn->qos_latency = latency;
6821     conn->qos_delay_variation = delay_variation;
6822     hci_run();
6823     return ERROR_CODE_SUCCESS;
6824 }
6825 
6826 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6827     hci_stack->new_page_scan_interval = page_scan_interval;
6828     hci_stack->new_page_scan_window = page_scan_window;
6829     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6830     hci_run();
6831 }
6832 
6833 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6834     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6835     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6836     hci_run();
6837 }
6838 
6839 #endif
6840 
6841 void hci_halting_defer(void){
6842     if (hci_stack->state != HCI_STATE_HALTING) return;
6843     switch (hci_stack->substate){
6844         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6845         case HCI_HALTING_CLOSE:
6846             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6847             break;
6848         default:
6849             break;
6850     }
6851 }
6852 
6853 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6854 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6855     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6856     if (le_device_db_index >= le_device_db_max_count()) return;
6857     uint8_t offset = le_device_db_index >> 3;
6858     uint8_t mask = 1 << (le_device_db_index & 7);
6859     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6860     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6861     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6862         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6863     }
6864 }
6865 
6866 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6867 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6868 	if (le_device_db_index >= le_device_db_max_count()) return;
6869 	uint8_t offset = le_device_db_index >> 3;
6870 	uint8_t mask = 1 << (le_device_db_index & 7);
6871 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6872 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6873 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6874 	}
6875 }
6876 
6877 uint8_t gap_load_resolving_list_from_le_device_db(void){
6878 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6879 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6880 	}
6881 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6882 		// restart le resolving list update
6883 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6884 	}
6885 	return ERROR_CODE_SUCCESS;
6886 }
6887 #endif
6888 
6889 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6890 void hci_setup_test_connections_fuzz(void){
6891     hci_connection_t * conn;
6892 
6893     // default address: 66:55:44:33:00:01
6894     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6895 
6896     // setup Controller info
6897     hci_stack->num_cmd_packets = 255;
6898     hci_stack->acl_packets_total_num = 255;
6899 
6900     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6901     addr[5] = 0x01;
6902     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6903     conn->con_handle = addr[5];
6904     conn->role  = HCI_ROLE_SLAVE;
6905     conn->state = RECEIVED_CONNECTION_REQUEST;
6906     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6907 
6908     // setup incoming Classic SCO connection with con handle 0x0002
6909     addr[5] = 0x02;
6910     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6911     conn->con_handle = addr[5];
6912     conn->role  = HCI_ROLE_SLAVE;
6913     conn->state = RECEIVED_CONNECTION_REQUEST;
6914     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6915 
6916     // setup ready Classic ACL connection with con handle 0x0003
6917     addr[5] = 0x03;
6918     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6919     conn->con_handle = addr[5];
6920     conn->role  = HCI_ROLE_SLAVE;
6921     conn->state = OPEN;
6922     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6923 
6924     // setup ready Classic SCO connection with con handle 0x0004
6925     addr[5] = 0x04;
6926     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6927     conn->con_handle = addr[5];
6928     conn->role  = HCI_ROLE_SLAVE;
6929     conn->state = OPEN;
6930     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6931 
6932     // setup ready LE ACL connection with con handle 0x005 and public address
6933     addr[5] = 0x05;
6934     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6935     conn->con_handle = addr[5];
6936     conn->role  = HCI_ROLE_SLAVE;
6937     conn->state = OPEN;
6938     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6939     conn->sm_connection.sm_connection_encrypted = 1;
6940 }
6941 
6942 void hci_free_connections_fuzz(void){
6943     btstack_linked_list_iterator_t it;
6944     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6945     while (btstack_linked_list_iterator_has_next(&it)){
6946         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6947         btstack_linked_list_iterator_remove(&it);
6948         btstack_memory_hci_connection_free(con);
6949     }
6950 }
6951 void hci_simulate_working_fuzz(void){
6952     hci_init_done();
6953     hci_stack->num_cmd_packets = 255;
6954 }
6955 #endif
6956