xref: /btstack/src/hci.c (revision f4c579d45b11af71e6484c0678b5a8aa5ea0f7d6)
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_SEND_BAUD_CHANGE:
1488             if (need_baud_change) {
1489                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1490                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1491                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1492                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1493                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1494                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1495                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1496                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1497                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1498                     btstack_run_loop_add_timer(&hci_stack->timeout);
1499                }
1500                break;
1501             }
1502 
1503             /* fall through */
1504 
1505         case HCI_INIT_CUSTOM_INIT:
1506             // Custom initialization
1507             if (hci_stack->chipset && hci_stack->chipset->next_command){
1508                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1509                 bool send_cmd = false;
1510                 switch (hci_stack->chipset_result){
1511                     case BTSTACK_CHIPSET_VALID_COMMAND:
1512                         send_cmd = true;
1513                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1514                         break;
1515                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1516                         send_cmd = true;
1517                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1518                         log_info("CSR Warm Boot");
1519                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1520                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1521                         btstack_run_loop_add_timer(&hci_stack->timeout);
1522                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1523                             && hci_stack->config
1524                             && hci_stack->chipset
1525                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1526                             && hci_stack->hci_transport->set_baudrate
1527                             && hci_transport_uart_get_main_baud_rate()){
1528                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1529                         } else {
1530                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1531                         }
1532                         break;
1533                     default:
1534                         break;
1535                 }
1536 
1537                 if (send_cmd){
1538                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1539                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1540                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1541                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1542                     break;
1543                 }
1544                 log_info("Init script done");
1545 
1546                 // Init script download on Broadcom chipsets causes:
1547                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1548                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1549                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1550 
1551                     // - baud rate to reset, restore UART baud rate if needed
1552                     if (need_baud_change) {
1553                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1554                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1555                         hci_stack->hci_transport->set_baudrate(baud_rate);
1556                     }
1557 
1558                     uint16_t bcm_delay_ms = 300;
1559                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1560                     //   -> Work around: wait here.
1561                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1562                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1563                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1564                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1565                     btstack_run_loop_add_timer(&hci_stack->timeout);
1566                     break;
1567                 }
1568             }
1569             // otherwise continue
1570             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1571             hci_send_cmd(&hci_read_local_supported_commands);
1572             break;
1573         case HCI_INIT_SET_BD_ADDR:
1574             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1575             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1576             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1577             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1578             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1579             break;
1580 #endif
1581 
1582         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1583             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1584             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1585             hci_send_cmd(&hci_read_local_supported_commands);
1586             break;
1587         case HCI_INIT_READ_BD_ADDR:
1588             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1589             hci_send_cmd(&hci_read_bd_addr);
1590             break;
1591         case HCI_INIT_READ_BUFFER_SIZE:
1592             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1593             hci_send_cmd(&hci_read_buffer_size);
1594             break;
1595         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1596             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1597             hci_send_cmd(&hci_read_local_supported_features);
1598             break;
1599 
1600 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1601         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1602             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1603             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1604             break;
1605         case HCI_INIT_HOST_BUFFER_SIZE:
1606             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1607             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1608                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1609             break;
1610 #endif
1611 
1612         case HCI_INIT_SET_EVENT_MASK:
1613             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1614             if (hci_le_supported()){
1615                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1616             } else {
1617                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1618                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1619             }
1620             break;
1621 
1622 #ifdef ENABLE_CLASSIC
1623         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1624             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1625             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1626             break;
1627         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1628             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1629             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1630             break;
1631         case HCI_INIT_WRITE_INQUIRY_MODE:
1632             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1633             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1634             break;
1635         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1636             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1637 			hci_stack->secure_connections_active = true;
1638             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1639             break;
1640         // only sent if ENABLE_SCO_OVER_HCI is defined
1641         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1642             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1643             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1644             break;
1645         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1646             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1647             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1648             break;
1649         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1650         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1651             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1652 #ifdef ENABLE_SCO_OVER_HCI
1653             log_info("BCM: Route SCO data via HCI transport");
1654             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1655 #endif
1656 #ifdef ENABLE_SCO_OVER_PCM
1657             log_info("BCM: Route SCO data via PCM interface");
1658 #ifdef ENABLE_BCM_PCM_WBS
1659             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1660             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1661 #else
1662             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1663             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1664 #endif
1665 #endif
1666             break;
1667 #ifdef ENABLE_SCO_OVER_PCM
1668         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1669             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1670             log_info("BCM: Config PCM interface for I2S");
1671 #ifdef ENABLE_BCM_PCM_WBS
1672             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1673             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1674 #else
1675             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1676             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1677 #endif
1678             break;
1679 #endif
1680 #endif
1681 
1682 #ifdef ENABLE_BLE
1683         // LE INIT
1684         case HCI_INIT_LE_READ_BUFFER_SIZE:
1685             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1686             hci_send_cmd(&hci_le_read_buffer_size);
1687             break;
1688         case HCI_INIT_LE_SET_EVENT_MASK:
1689             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1690             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1691             break;
1692         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1693             // LE Supported Host = 1, Simultaneous Host = 0
1694             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1695             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1696             break;
1697 #endif
1698 
1699 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1700         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1701             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1702             hci_send_cmd(&hci_le_read_maximum_data_length);
1703             break;
1704         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1705             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1706             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1707             break;
1708 #endif
1709 
1710 #ifdef ENABLE_LE_CENTRAL
1711         case HCI_INIT_READ_WHITE_LIST_SIZE:
1712             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1713             hci_send_cmd(&hci_le_read_white_list_size);
1714             break;
1715         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1716             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1717             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);
1718             break;
1719 #endif
1720         default:
1721             return;
1722     }
1723 }
1724 
1725 static void hci_init_done(void){
1726 #ifdef ENABLE_CLASSIC
1727     // init sequence complete, check if GAP Tasks are completed
1728     if (hci_stack->gap_tasks != 0) {
1729         hci_run_gap_tasks_classic();
1730         return;
1731     }
1732 #endif
1733 
1734     // done. tell the app
1735     log_info("hci_init_done -> HCI_STATE_WORKING");
1736     hci_stack->state = HCI_STATE_WORKING;
1737     hci_emit_state();
1738     hci_run();
1739 }
1740 
1741 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1742     bool command_completed = false;
1743     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1744         uint16_t opcode = little_endian_read_16(packet,3);
1745         if (opcode == hci_stack->last_cmd_opcode){
1746             command_completed = true;
1747             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1748         } else {
1749             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1750         }
1751     }
1752 
1753     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1754         uint8_t  status = packet[2];
1755         uint16_t opcode = little_endian_read_16(packet,4);
1756         if (opcode == hci_stack->last_cmd_opcode){
1757             if (status){
1758                 command_completed = true;
1759                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1760             } else {
1761                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1762             }
1763         } else {
1764             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1765         }
1766     }
1767 #ifndef HAVE_HOST_CONTROLLER_API
1768     // Vendor == CSR
1769     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1770         // TODO: track actual command
1771         command_completed = true;
1772     }
1773 
1774     // Vendor == Toshiba
1775     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1776         // TODO: track actual command
1777         command_completed = true;
1778         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1779         hci_stack->num_cmd_packets = 1;
1780     }
1781 #endif
1782 
1783     return command_completed;
1784 }
1785 
1786 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1787 
1788     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1789 
1790     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1791 
1792 #ifndef HAVE_HOST_CONTROLLER_API
1793 
1794     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1795     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1796     //
1797     // HCI Reset
1798     // Timeout 100 ms
1799     // HCI Reset
1800     // Command Complete Reset
1801     // HCI Read Local Version Information
1802     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1803     // hang...
1804     //
1805     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1806     if (!command_completed
1807             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1808             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1809 
1810         uint16_t opcode = little_endian_read_16(packet,3);
1811         if (opcode == hci_reset.opcode){
1812             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1813             return;
1814         }
1815     }
1816 
1817     // CSR & H5
1818     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1819     if (!command_completed
1820             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1821             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1822 
1823         uint16_t opcode = little_endian_read_16(packet,3);
1824         if (opcode == hci_reset.opcode){
1825             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1826             return;
1827         }
1828     }
1829 
1830     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1831     // fix: Correct substate and behave as command below
1832     if (command_completed){
1833         switch (hci_stack->substate){
1834             case HCI_INIT_SEND_RESET:
1835                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1836                 break;
1837             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1838                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1839                 break;
1840             default:
1841                 break;
1842         }
1843     }
1844 
1845 #endif
1846 
1847     if (!command_completed) return;
1848 
1849     bool need_baud_change = false;
1850     bool need_addr_change = false;
1851 
1852 #ifndef HAVE_HOST_CONTROLLER_API
1853     need_baud_change = hci_stack->config
1854                         && hci_stack->chipset
1855                         && hci_stack->chipset->set_baudrate_command
1856                         && hci_stack->hci_transport->set_baudrate
1857                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1858 
1859     need_addr_change = hci_stack->custom_bd_addr_set
1860                         && hci_stack->chipset
1861                         && hci_stack->chipset->set_bd_addr_command;
1862 #endif
1863 
1864     switch(hci_stack->substate){
1865 
1866 #ifndef HAVE_HOST_CONTROLLER_API
1867         case HCI_INIT_SEND_RESET:
1868             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1869             // fix: just correct substate and behave as command below
1870 
1871             /* fall through */
1872 #endif
1873 
1874         case HCI_INIT_W4_SEND_RESET:
1875             btstack_run_loop_remove_timer(&hci_stack->timeout);
1876             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1877             return;
1878 
1879 #ifndef HAVE_HOST_CONTROLLER_API
1880         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1881             // for STLC2500D, baud rate change already happened.
1882             // for others, baud rate gets changed now
1883             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1884                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1885                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1886                 hci_stack->hci_transport->set_baudrate(baud_rate);
1887             }
1888             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1889             return;
1890         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1891             btstack_run_loop_remove_timer(&hci_stack->timeout);
1892             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1893             return;
1894         case HCI_INIT_W4_CUSTOM_INIT:
1895             // repeat custom init
1896             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1897             return;
1898 #endif
1899 
1900         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1901             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1902               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1903                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1904                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1905                 return;
1906             }
1907             if (need_addr_change){
1908                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1909                 return;
1910             }
1911             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1912             return;
1913 #ifndef HAVE_HOST_CONTROLLER_API
1914         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1915             if (need_baud_change){
1916                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1917                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1918                 hci_stack->hci_transport->set_baudrate(baud_rate);
1919             }
1920             if (need_addr_change){
1921                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1922                 return;
1923             }
1924             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1925             return;
1926         case HCI_INIT_W4_SET_BD_ADDR:
1927             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1928             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1929             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1930                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1931                 return;
1932             }
1933             // skipping st warm boot
1934             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1935             return;
1936         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1937             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1938             return;
1939 #endif
1940         case HCI_INIT_W4_READ_BD_ADDR:
1941             // only read buffer size if supported
1942             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1943                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1944                 return;
1945             }
1946             // skipping read buffer size
1947             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1948             return;
1949         case HCI_INIT_W4_SET_EVENT_MASK:
1950             // skip Classic init commands for LE only chipsets
1951             if (!hci_classic_supported()){
1952 #ifdef ENABLE_BLE
1953                 if (hci_le_supported()){
1954                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1955                     return;
1956                 }
1957 #endif
1958                 log_error("Neither BR/EDR nor LE supported");
1959                 hci_init_done();
1960                 return;
1961             }
1962             if (!gap_ssp_supported()){
1963                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1964                 return;
1965             }
1966             break;
1967 #ifdef ENABLE_BLE
1968         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1969             // skip write le host if not supported (e.g. on LE only EM9301)
1970             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1971             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1972             return;
1973 
1974 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1975         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1976             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1977             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1978                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1979                 return;
1980             }
1981             // explicit fall through to reduce repetitions
1982 
1983 #ifdef ENABLE_LE_CENTRAL
1984             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1985 #else
1986             hci_init_done();
1987 #endif
1988             return;
1989 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1990 
1991 #endif  /* ENABLE_BLE */
1992 
1993         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1994             // skip write secure connections host support if not supported or disabled
1995             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1996                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1997                 return;
1998             }
1999             break;
2000 
2001 #ifdef ENABLE_SCO_OVER_HCI
2002         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2003             // skip write synchronous flow control if not supported
2004             if (hci_stack->local_supported_commands[0] & 0x04) break;
2005             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
2006 
2007             /* fall through */
2008 
2009         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2010             // skip write default erroneous data reporting if not supported
2011             if (hci_stack->local_supported_commands[0] & 0x08) break;
2012             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
2013 
2014             /* fall through */
2015 
2016         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
2017             // skip bcm set sco pcm config on non-Broadcom chipsets
2018             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
2019             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2020 
2021             /* fall through */
2022 
2023         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
2024             if (!hci_le_supported()){
2025                 // SKIP LE init for Classic only configuration
2026                 hci_init_done();
2027                 return;
2028             }
2029             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
2030             break;
2031 
2032 #else /* !ENABLE_SCO_OVER_HCI */
2033 
2034         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
2035 #ifdef ENABLE_SCO_OVER_PCM
2036             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
2037                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
2038                 return;
2039             }
2040 #endif
2041             /* fall through */
2042 
2043         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
2044 #ifdef ENABLE_BLE
2045             if (hci_le_supported()){
2046                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
2047                 return;
2048             }
2049 #endif
2050             // SKIP LE init for Classic only configuration
2051             hci_init_done();
2052             return;
2053 #endif /* ENABLE_SCO_OVER_HCI */
2054 
2055 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2056 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2057         // Response to command before init done state -> init done
2058         case (HCI_INIT_DONE-1):
2059             hci_init_done();
2060             return;
2061 #endif
2062 
2063         default:
2064             break;
2065     }
2066     hci_initializing_next_state();
2067 }
2068 
2069 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2070     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2071     bd_addr_t bd_address;
2072     (void)memcpy(&bd_address, conn->address, 6);
2073 
2074 #ifdef ENABLE_CLASSIC
2075     // cache needed data
2076     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2077 #endif
2078 
2079     // connection failed, remove entry
2080     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2081     btstack_memory_hci_connection_free( conn );
2082 
2083 #ifdef ENABLE_CLASSIC
2084     // notify client if dedicated bonding
2085     if (notify_dedicated_bonding_failed){
2086         log_info("hci notify_dedicated_bonding_failed");
2087         hci_emit_dedicated_bonding_result(bd_address, status);
2088     }
2089 
2090     // if authentication error, also delete link key
2091     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2092         gap_drop_link_key_for_bd_addr(bd_address);
2093     }
2094 #else
2095     UNUSED(status);
2096 #endif
2097 }
2098 
2099 #ifdef ENABLE_CLASSIC
2100 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2101     // SSP Controller
2102     if (features[6] & (1 << 3)){
2103         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2104     }
2105     // eSCO
2106     if (features[3] & (1<<7)){
2107         conn->remote_supported_features[0] |= 1;
2108     }
2109     // Extended features
2110     if (features[7] & (1<<7)){
2111         conn->remote_supported_features[0] |= 2;
2112     }
2113 }
2114 
2115 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2116     // SSP Host
2117     if (features[0] & (1 << 0)){
2118         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2119     }
2120     // SC Host
2121     if (features[0] & (1 << 3)){
2122         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2123     }
2124 }
2125 
2126 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2127     // SC Controller
2128     if (features[1] & (1 << 0)){
2129         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2130     }
2131 }
2132 
2133 static void hci_handle_remote_features_received(hci_connection_t * conn){
2134     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2135     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2136     if (conn->bonding_flags & BONDING_DEDICATED){
2137         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2138     }
2139 }
2140 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2141     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2142     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2143 }
2144 
2145 #endif
2146 
2147 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2148     // handle BT initialization
2149     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2150         hci_initializing_event_handler(packet, size);
2151     }
2152 
2153     // help with BT sleep
2154     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2155         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2156         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2157         hci_initializing_next_state();
2158     }
2159 }
2160 
2161 #ifdef ENABLE_CLASSIC
2162 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2163     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2164     conn->encryption_key_size = encryption_key_size;
2165 
2166     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2167         conn->requested_security_level = LEVEL_0;
2168         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2169         return;
2170     }
2171 
2172     // Request Authentication if not already done
2173     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2174     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2175 }
2176 #endif
2177 
2178 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2179     UNUSED(size);
2180 
2181     uint16_t manufacturer;
2182 #ifdef ENABLE_CLASSIC
2183     hci_con_handle_t handle;
2184     hci_connection_t * conn;
2185     uint8_t status;
2186 #endif
2187     // get num cmd packets - limit to 1 to reduce complexity
2188     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2189 
2190     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2191     switch (opcode){
2192         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2193             if (packet[5]) break;
2194             // terminate, name 248 chars
2195             packet[6+248] = 0;
2196             log_info("local name: %s", &packet[6]);
2197             break;
2198         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2199             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2200             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2201                 uint16_t acl_len = little_endian_read_16(packet, 6);
2202                 uint16_t sco_len = packet[8];
2203 
2204                 // determine usable ACL/SCO payload size
2205                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2206                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2207 
2208                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2209                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2210 
2211                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2212                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2213                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2214             }
2215             break;
2216         case HCI_OPCODE_HCI_READ_RSSI:
2217             if (packet[5] == ERROR_CODE_SUCCESS){
2218                 uint8_t event[5];
2219                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2220                 event[1] = 3;
2221                 (void)memcpy(&event[2], &packet[6], 3);
2222                 hci_emit_event(event, sizeof(event), 1);
2223             }
2224             break;
2225 #ifdef ENABLE_BLE
2226         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2227             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2228             hci_stack->le_acl_packets_total_num = packet[8];
2229             // determine usable ACL payload size
2230             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2231                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2232             }
2233             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2234             break;
2235 #endif
2236 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2237         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2238             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2239             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2240             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);
2241             break;
2242 #endif
2243 #ifdef ENABLE_LE_CENTRAL
2244         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2245             hci_stack->le_whitelist_capacity = packet[6];
2246             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2247             break;
2248 #endif
2249         case HCI_OPCODE_HCI_READ_BD_ADDR:
2250             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2251             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));
2252 #ifdef ENABLE_CLASSIC
2253             if (hci_stack->link_key_db){
2254                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2255             }
2256 #endif
2257             break;
2258 #ifdef ENABLE_CLASSIC
2259         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2260             hci_emit_discoverable_enabled(hci_stack->discoverable);
2261             break;
2262         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2263             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2264                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2265                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2266                 hci_emit_event(event, sizeof(event), 1);
2267             }
2268             break;
2269 #endif
2270         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2271             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2272 
2273 #ifdef ENABLE_CLASSIC
2274             // determine usable ACL packet types based on host buffer size and supported features
2275             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2276             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2277 #endif
2278             // Classic/LE
2279             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2280             break;
2281         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2282             manufacturer = little_endian_read_16(packet, 10);
2283             // map Cypress to Broadcom
2284             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2285                 log_info("Treat Cypress as Broadcom");
2286                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2287                 little_endian_store_16(packet, 10, manufacturer);
2288             }
2289             hci_stack->manufacturer = manufacturer;
2290             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2291             break;
2292         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2293             hci_stack->local_supported_commands[0] =
2294                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2295                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2296                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2297                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2298                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2299                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2300                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2301                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2302             hci_stack->local_supported_commands[1] =
2303                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2304                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2305                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2306                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2307                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2308             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2309             break;
2310 #ifdef ENABLE_CLASSIC
2311         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2312             if (packet[5]) return;
2313             hci_stack->synchronous_flow_control_enabled = 1;
2314             break;
2315         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2316             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2317             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2318             conn   = hci_connection_for_handle(handle);
2319             if (conn != NULL) {
2320                 uint8_t key_size = 0;
2321                 if (status == 0){
2322                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2323                     log_info("Handle %04x key Size: %u", handle, key_size);
2324                 } else {
2325                     key_size = 1;
2326                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2327                 }
2328                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2329             }
2330             break;
2331         // assert pairing complete event is emitted.
2332         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2333         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2334         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2335         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2336             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2337             // lookup connection by gap pairing addr
2338             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2339             if (conn == NULL) break;
2340             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2341             break;
2342 
2343 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2344         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2345         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2346             uint8_t event[67];
2347             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2348             event[1] = 65;
2349             (void)memset(&event[2], 0, 65);
2350             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2351                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2352                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2353                     event[2] = 3;
2354                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2355                 } else {
2356                     event[2] = 1;
2357                 }
2358             }
2359             hci_emit_event(event, sizeof(event), 0);
2360             break;
2361         }
2362 
2363         // note: only needed if user does not provide OOB data
2364         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2365             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2366             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2367             if (conn == NULL) break;
2368             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2369             break;
2370 #endif
2371 #endif
2372         default:
2373             break;
2374     }
2375 }
2376 
2377 #ifdef ENABLE_BLE
2378 static void event_handle_le_connection_complete(const uint8_t * packet){
2379 	bd_addr_t addr;
2380 	bd_addr_type_t addr_type;
2381 	hci_connection_t * conn;
2382 
2383 	// Connection management
2384 	reverse_bd_addr(&packet[8], addr);
2385 	addr_type = (bd_addr_type_t)packet[7];
2386 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2387 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2388 
2389 #ifdef ENABLE_LE_CENTRAL
2390 	// handle error: error is reported only to the initiator -> outgoing connection
2391 	if (packet[3]){
2392 
2393 		// handle cancelled outgoing connection
2394 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2395 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2396 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2397 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2398 		    // reset state
2399             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2400             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2401 			// get outgoing connection conn struct for direct connect
2402 			conn = gap_get_outgoing_connection();
2403 		}
2404 
2405 		// outgoing le connection establishment is done
2406 		if (conn){
2407 			// remove entry
2408 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2409 			btstack_memory_hci_connection_free( conn );
2410 		}
2411 		return;
2412 	}
2413 #endif
2414 
2415 	// on success, both hosts receive connection complete event
2416 	if (packet[6] == HCI_ROLE_MASTER){
2417 #ifdef ENABLE_LE_CENTRAL
2418 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2419 		// note: no hci_connection_t object exists yet for connect with whitelist
2420 		if (hci_is_le_connection_type(addr_type)){
2421 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2422 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2423 		}
2424 #endif
2425 	} else {
2426 #ifdef ENABLE_LE_PERIPHERAL
2427 		// if we're slave, it was an incoming connection, advertisements have stopped
2428 		hci_stack->le_advertisements_active = false;
2429 #endif
2430 	}
2431 
2432 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2433 	if (!conn){
2434 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2435 	}
2436 
2437 	// no memory, sorry.
2438 	if (!conn){
2439 		return;
2440 	}
2441 
2442 	conn->state = OPEN;
2443 	conn->role  = packet[6];
2444 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2445 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2446 
2447 #ifdef ENABLE_LE_PERIPHERAL
2448 	if (packet[6] == HCI_ROLE_SLAVE){
2449 		hci_update_advertisements_enabled_for_current_roles();
2450 	}
2451 #endif
2452 
2453     // init unenhanced att bearer mtu
2454     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2455     conn->att_connection.mtu_exchanged = false;
2456 
2457     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2458 
2459 	// restart timer
2460 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2461 	// btstack_run_loop_add_timer(&conn->timeout);
2462 
2463 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2464 
2465 	hci_emit_nr_connections_changed();
2466 }
2467 #endif
2468 
2469 #ifdef ENABLE_CLASSIC
2470 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){
2471     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2472     // LEVEL_4 is tested by l2cap
2473     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2474     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2475     if (level >= LEVEL_3){
2476         // MITM not possible without keyboard or display
2477         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2478         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2479 
2480         // MITM possible if one side has keyboard and the other has keyboard or display
2481         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2482         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2483 
2484         // MITM not possible if one side has only display and other side has no keyboard
2485         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2486         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2487     }
2488     // LEVEL 2 requires SSP, which is a given
2489     return true;
2490 }
2491 
2492 static bool btstack_is_null(uint8_t * data, uint16_t size){
2493     uint16_t i;
2494     for (i=0; i < size ; i++){
2495         if (data[i] != 0) {
2496             return false;
2497         }
2498     }
2499     return true;
2500 }
2501 
2502 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2503     // get requested security level
2504     gap_security_level_t requested_security_level = conn->requested_security_level;
2505     if (hci_stack->gap_secure_connections_only_mode){
2506         requested_security_level = LEVEL_4;
2507     }
2508 
2509     // assess security: LEVEL 4 requires SC
2510     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2511     if ((requested_security_level == LEVEL_4) &&
2512         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2513         !hci_remote_sc_enabled(conn)){
2514         log_info("Level 4 required, but SC not supported -> abort");
2515         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2516         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2517         return;
2518     }
2519 
2520     // assess security based on io capabilities
2521     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2522         // responder: fully validate io caps of both sides as well as OOB data
2523         bool security_possible = false;
2524         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2525 
2526 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2527         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2528         // so we merge the OOB data availability
2529         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2530         if (conn->classic_oob_c_192 != NULL){
2531             have_oob_data |= 1;
2532         }
2533         if (conn->classic_oob_c_256 != NULL){
2534             have_oob_data |= 2;
2535         }
2536         // for up to Level 3, either P-192 as well as P-256 will do
2537         // 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
2538         // if remote does not SC, we should not receive P-256 data either
2539         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2540             security_possible = true;
2541         }
2542         // for Level 4, P-256 is needed
2543         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2544             security_possible = true;
2545         }
2546 #endif
2547 
2548         if (security_possible == false){
2549             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2550             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2551             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2552             return;
2553         }
2554     } else {
2555         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2556 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2557 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2558         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2559             log_info("Level 3+ required, but no input/output -> abort");
2560             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2561             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2562             return;
2563         }
2564 #endif
2565 #endif
2566     }
2567 
2568 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2569     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2570         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2571     } else {
2572         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2573     }
2574 #endif
2575 }
2576 
2577 #endif
2578 
2579 static void event_handler(uint8_t *packet, uint16_t size){
2580 
2581     uint16_t event_length = packet[1];
2582 
2583     // assert packet is complete
2584     if (size != (event_length + 2u)){
2585         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2586         return;
2587     }
2588 
2589     bd_addr_type_t addr_type;
2590     hci_con_handle_t handle;
2591     hci_connection_t * conn;
2592     int i;
2593     int create_connection_cmd;
2594 
2595 #ifdef ENABLE_CLASSIC
2596     hci_link_type_t link_type;
2597     bd_addr_t addr;
2598 #endif
2599 
2600     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2601 
2602     switch (hci_event_packet_get_type(packet)) {
2603 
2604         case HCI_EVENT_COMMAND_COMPLETE:
2605             handle_command_complete_event(packet, size);
2606             break;
2607 
2608         case HCI_EVENT_COMMAND_STATUS:
2609             // get num cmd packets - limit to 1 to reduce complexity
2610             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2611 
2612             // check command status to detected failed outgoing connections
2613             create_connection_cmd = 0;
2614 #ifdef ENABLE_CLASSIC
2615             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2616                 create_connection_cmd = 1;
2617             }
2618 #endif
2619 #ifdef ENABLE_LE_CENTRAL
2620             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2621                 create_connection_cmd = 1;
2622             }
2623 #endif
2624             if (create_connection_cmd) {
2625                 uint8_t status = hci_event_command_status_get_status(packet);
2626                 addr_type = hci_stack->outgoing_addr_type;
2627                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2628                 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);
2629 
2630                 // reset outgoing address info
2631                 memset(hci_stack->outgoing_addr, 0, 6);
2632                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2633 
2634                 // on error
2635                 if (status != ERROR_CODE_SUCCESS){
2636 #ifdef ENABLE_LE_CENTRAL
2637                     if (hci_is_le_connection_type(addr_type)){
2638                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2639                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2640                     }
2641 #endif
2642                     // error => outgoing connection failed
2643                     if (conn != NULL){
2644                         hci_handle_connection_failed(conn, status);
2645                     }
2646                 }
2647             }
2648 
2649 #ifdef ENABLE_CLASSIC
2650             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2651                 uint8_t status = hci_event_command_status_get_status(packet);
2652                 log_info("command status (inquiry), status %x", status);
2653                 if (status == ERROR_CODE_SUCCESS) {
2654                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2655                 } else {
2656                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2657                 }
2658             }
2659 #endif
2660             break;
2661 
2662         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2663             if (size < 3) return;
2664             uint16_t num_handles = packet[2];
2665             if (size != (3u + num_handles * 4u)) return;
2666             uint16_t offset = 3;
2667             for (i=0; i<num_handles;i++){
2668                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2669                 offset += 2u;
2670                 uint16_t num_packets = little_endian_read_16(packet, offset);
2671                 offset += 2u;
2672 
2673                 conn = hci_connection_for_handle(handle);
2674                 if (!conn){
2675                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2676                     continue;
2677                 }
2678 
2679                 if (conn->num_packets_sent >= num_packets){
2680                     conn->num_packets_sent -= num_packets;
2681                 } else {
2682                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2683                     conn->num_packets_sent = 0;
2684                 }
2685                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2686 
2687 #ifdef ENABLE_CLASSIC
2688                 // For SCO, we do the can_send_now_check here
2689                 hci_notify_if_sco_can_send_now();
2690 #endif
2691             }
2692             break;
2693         }
2694 
2695 #ifdef ENABLE_CLASSIC
2696         case HCI_EVENT_INQUIRY_COMPLETE:
2697             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2698                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2699                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2700                 hci_emit_event(event, sizeof(event), 1);
2701             }
2702             break;
2703         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2704             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2705                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2706             }
2707             break;
2708         case HCI_EVENT_CONNECTION_REQUEST:
2709             reverse_bd_addr(&packet[2], addr);
2710             link_type = (hci_link_type_t) packet[11];
2711 
2712             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2713             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2714                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2715                 bd_addr_copy(hci_stack->decline_addr, addr);
2716                 break;
2717             }
2718 
2719             if (hci_stack->gap_classic_accept_callback != NULL){
2720                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2721                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2722                     bd_addr_copy(hci_stack->decline_addr, addr);
2723                     break;
2724                 }
2725             }
2726 
2727             // TODO: eval COD 8-10
2728             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2729             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2730             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2731             if (!conn) {
2732                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2733             }
2734             if (!conn) {
2735                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2736                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2737                 bd_addr_copy(hci_stack->decline_addr, addr);
2738                 break;
2739             }
2740             conn->role  = HCI_ROLE_SLAVE;
2741             conn->state = RECEIVED_CONNECTION_REQUEST;
2742             // store info about eSCO
2743             if (link_type == HCI_LINK_TYPE_ESCO){
2744                 conn->remote_supported_features[0] |= 1;
2745             }
2746             hci_run();
2747             break;
2748 
2749         case HCI_EVENT_CONNECTION_COMPLETE:
2750             // Connection management
2751             reverse_bd_addr(&packet[5], addr);
2752             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2753             addr_type = BD_ADDR_TYPE_ACL;
2754             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2755             if (conn) {
2756                 if (!packet[2]){
2757                     conn->state = OPEN;
2758                     conn->con_handle = little_endian_read_16(packet, 3);
2759 
2760                     // queue get remote feature
2761                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2762 
2763                     // queue set supervision timeout if we're master
2764                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2765                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2766                     }
2767 
2768                     // restart timer
2769                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2770                     btstack_run_loop_add_timer(&conn->timeout);
2771 
2772                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2773 
2774                     hci_emit_nr_connections_changed();
2775                 } else {
2776                     // connection failed
2777                     hci_handle_connection_failed(conn, packet[2]);
2778                 }
2779             }
2780             break;
2781 
2782         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2783             reverse_bd_addr(&packet[5], addr);
2784             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2785             if (packet[2]){
2786                 // connection failed
2787                 break;
2788             }
2789             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2790             if (!conn) {
2791                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2792             }
2793             if (!conn) {
2794                 break;
2795             }
2796             conn->state = OPEN;
2797             conn->con_handle = little_endian_read_16(packet, 3);
2798 
2799 #ifdef ENABLE_SCO_OVER_HCI
2800             // update SCO
2801             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2802                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2803             }
2804             // trigger can send now
2805             if (hci_have_usb_transport()){
2806                 hci_stack->sco_can_send_now = true;
2807             }
2808 #endif
2809 #ifdef HAVE_SCO_TRANSPORT
2810             // configure sco transport
2811             if (hci_stack->sco_transport != NULL){
2812                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2813                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2814             }
2815 #endif
2816             break;
2817 
2818         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2819             handle = little_endian_read_16(packet, 3);
2820             conn = hci_connection_for_handle(handle);
2821             if (!conn) break;
2822             if (!packet[2]){
2823                 const uint8_t * features = &packet[5];
2824                 hci_handle_remote_features_page_0(conn, features);
2825 
2826                 // read extended features if possible
2827                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2828                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2829                     break;
2830                 }
2831             }
2832             hci_handle_remote_features_received(conn);
2833             break;
2834 
2835         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2836             handle = little_endian_read_16(packet, 3);
2837             conn = hci_connection_for_handle(handle);
2838             if (!conn) break;
2839             // status = ok, page = 1
2840             if (!packet[2]) {
2841                 uint8_t page_number = packet[5];
2842                 uint8_t maximum_page_number = packet[6];
2843                 const uint8_t * features = &packet[7];
2844                 bool done = false;
2845                 switch (page_number){
2846                     case 1:
2847                         hci_handle_remote_features_page_1(conn, features);
2848                         if (maximum_page_number >= 2){
2849                             // get Secure Connections (Controller) from Page 2 if available
2850                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2851                         } else {
2852                             // otherwise, assume SC (Controller) == SC (Host)
2853                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2854                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2855                             }
2856                             done = true;
2857                         }
2858                         break;
2859                     case 2:
2860                         hci_handle_remote_features_page_2(conn, features);
2861                         done = true;
2862                         break;
2863                     default:
2864                         break;
2865                 }
2866                 if (!done) break;
2867             }
2868             hci_handle_remote_features_received(conn);
2869             break;
2870 
2871         case HCI_EVENT_LINK_KEY_REQUEST:
2872 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2873             hci_event_link_key_request_get_bd_addr(packet, addr);
2874             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2875             if (!conn) break;
2876 
2877             // lookup link key in db if not cached
2878             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2879                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2880             }
2881 
2882             // response sent by hci_run()
2883             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2884 #endif
2885             break;
2886 
2887         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2888             hci_event_link_key_request_get_bd_addr(packet, addr);
2889             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2890             if (!conn) break;
2891 
2892             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2893 
2894             // CVE-2020-26555: ignore NULL link key
2895             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2896             if (btstack_is_null(&packet[8], 16)) break;
2897 
2898             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2899             // Change Connection Encryption keeps link key type
2900             if (link_key_type != CHANGED_COMBINATION_KEY){
2901                 conn->link_key_type = link_key_type;
2902             }
2903 
2904             // cache link key. link keys stored in little-endian format for legacy reasons
2905             memcpy(&conn->link_key, &packet[8], 16);
2906 
2907             // only store link key:
2908             // - if bondable enabled
2909             if (hci_stack->bondable == false) break;
2910             // - if security level sufficient
2911             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2912             // - for SSP, also check if remote side requested bonding as well
2913             if (conn->link_key_type != COMBINATION_KEY){
2914                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2915                 if (!remote_bonding){
2916                     break;
2917                 }
2918             }
2919             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2920             break;
2921         }
2922 
2923         case HCI_EVENT_PIN_CODE_REQUEST:
2924             hci_event_pin_code_request_get_bd_addr(packet, addr);
2925             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2926             if (!conn) break;
2927 
2928             hci_pairing_started(conn, false);
2929             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2930             if (!hci_stack->bondable ){
2931                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2932                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2933                 hci_run();
2934                 return;
2935             }
2936             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2937             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2938                 log_info("Level 4 required, but SC not supported -> abort");
2939                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2940                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2941                 hci_run();
2942                 return;
2943             }
2944             break;
2945 
2946         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2947             hci_event_io_capability_response_get_bd_addr(packet, addr);
2948             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2949             if (!conn) break;
2950 
2951             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2952             hci_pairing_started(conn, true);
2953             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2954             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2955 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2956             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2957 #endif
2958             break;
2959 
2960         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2961             hci_event_io_capability_response_get_bd_addr(packet, addr);
2962             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2963             if (!conn) break;
2964 
2965             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2966             hci_connection_timestamp(conn);
2967             hci_pairing_started(conn, true);
2968             break;
2969 
2970 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2971         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2972             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2973             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2974             if (!conn) break;
2975 
2976             hci_connection_timestamp(conn);
2977 
2978             hci_pairing_started(conn, true);
2979 
2980             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2981             break;
2982 #endif
2983 
2984         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2985             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2986             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2987             if (!conn) break;
2988             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2989                 if (hci_stack->ssp_auto_accept){
2990                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2991                 };
2992             } else {
2993                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2994                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2995                 // don't forward event to app
2996                 hci_run();
2997                 return;
2998             }
2999             break;
3000 
3001         case HCI_EVENT_USER_PASSKEY_REQUEST:
3002             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
3003             if (hci_stack->ssp_auto_accept){
3004                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
3005             };
3006             break;
3007 
3008         case HCI_EVENT_MODE_CHANGE:
3009             handle = hci_event_mode_change_get_handle(packet);
3010             conn = hci_connection_for_handle(handle);
3011             if (!conn) break;
3012             conn->connection_mode = hci_event_mode_change_get_mode(packet);
3013             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
3014             break;
3015 #endif
3016 
3017         case HCI_EVENT_ENCRYPTION_CHANGE:
3018             handle = hci_event_encryption_change_get_connection_handle(packet);
3019             conn = hci_connection_for_handle(handle);
3020             if (!conn) break;
3021             if (hci_event_encryption_change_get_status(packet) == 0u) {
3022                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
3023                 if (encryption_enabled){
3024                     if (hci_is_le_connection(conn)){
3025                         // For LE, we accept connection as encrypted
3026                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3027                     }
3028 #ifdef ENABLE_CLASSIC
3029                     else {
3030 
3031                         // dedicated bonding: send result and disconnect
3032                         if (conn->bonding_flags & BONDING_DEDICATED){
3033                             conn->bonding_flags &= ~BONDING_DEDICATED;
3034                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3035                             conn->bonding_status = packet[2];
3036                             break;
3037                         }
3038 
3039                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3040                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3041                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3042                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3043                             log_info("SC during pairing, but only E0 now -> abort");
3044                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3045                             break;
3046                         }
3047 
3048                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3049                         if (connected_uses_aes_ccm){
3050                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3051                         }
3052 
3053 #ifdef ENABLE_TESTING_SUPPORT
3054                         // work around for issue with PTS dongle
3055                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3056 #endif
3057 
3058                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3059                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3060                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3061                         } else {
3062                             // if not, pretend everything is perfect
3063                             hci_handle_read_encryption_key_size_complete(conn, 16);
3064                         }
3065                     }
3066 #endif
3067                 } else {
3068                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3069                 }
3070             }
3071 
3072             break;
3073 
3074 #ifdef ENABLE_CLASSIC
3075         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3076             handle = hci_event_authentication_complete_get_connection_handle(packet);
3077             conn = hci_connection_for_handle(handle);
3078             if (!conn) break;
3079 
3080             // clear authentication active flag
3081             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3082             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3083 
3084             // authenticated only if auth status == 0
3085             if (hci_event_authentication_complete_get_status(packet) == 0){
3086                 // authenticated
3087                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3088 
3089                 // If not already encrypted, start encryption
3090                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3091                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3092                     break;
3093                 }
3094             }
3095 
3096             // emit updated security level
3097             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3098             break;
3099 
3100         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3101             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3102             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3103             if (!conn) break;
3104 
3105             // treat successfully paired connection as authenticated
3106             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3107                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3108             }
3109 
3110             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3111             break;
3112 #endif
3113 
3114         // HCI_EVENT_DISCONNECTION_COMPLETE
3115         // has been split, to first notify stack before shutting connection down
3116         // see end of function, too.
3117         case HCI_EVENT_DISCONNECTION_COMPLETE:
3118             if (packet[2]) break;   // status != 0
3119             handle = little_endian_read_16(packet, 3);
3120             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3121             if (hci_stack->acl_fragmentation_total_size > 0u) {
3122                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3123                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3124                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3125                     hci_stack->acl_fragmentation_total_size = 0;
3126                     hci_stack->acl_fragmentation_pos = 0;
3127                     if (release_buffer){
3128                         hci_release_packet_buffer();
3129                     }
3130                 }
3131             }
3132 
3133             conn = hci_connection_for_handle(handle);
3134             if (!conn) break;
3135 #ifdef ENABLE_CLASSIC
3136             // pairing failed if it was ongoing
3137             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3138 #endif
3139 
3140             // emit dedicatd bonding event
3141             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3142                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3143             }
3144 
3145             // mark connection for shutdown, stop timers, reset state
3146             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3147             hci_connection_stop_timer(conn);
3148             hci_connection_init(conn);
3149 
3150 #ifdef ENABLE_BLE
3151 #ifdef ENABLE_LE_PERIPHERAL
3152             // re-enable advertisements for le connections if active
3153             if (hci_is_le_connection(conn)){
3154                 hci_update_advertisements_enabled_for_current_roles();
3155             }
3156 #endif
3157 #endif
3158             break;
3159 
3160         case HCI_EVENT_HARDWARE_ERROR:
3161             log_error("Hardware Error: 0x%02x", packet[2]);
3162             if (hci_stack->hardware_error_callback){
3163                 (*hci_stack->hardware_error_callback)(packet[2]);
3164             } else {
3165                 // if no special requests, just reboot stack
3166                 hci_power_control_off();
3167                 hci_power_control_on();
3168             }
3169             break;
3170 
3171 #ifdef ENABLE_CLASSIC
3172         case HCI_EVENT_ROLE_CHANGE:
3173             if (packet[2]) break;   // status != 0
3174             reverse_bd_addr(&packet[3], addr);
3175             addr_type = BD_ADDR_TYPE_ACL;
3176             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3177             if (!conn) break;
3178             conn->role = packet[9];
3179             break;
3180 #endif
3181 
3182         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3183             // release packet buffer only for asynchronous transport and if there are not further fragements
3184             if (hci_transport_synchronous()) {
3185                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3186                 return; // instead of break: to avoid re-entering hci_run()
3187             }
3188             hci_stack->acl_fragmentation_tx_active = 0;
3189             if (hci_stack->acl_fragmentation_total_size) break;
3190             hci_release_packet_buffer();
3191 
3192             // L2CAP receives this event via the hci_emit_event below
3193 
3194 #ifdef ENABLE_CLASSIC
3195             // For SCO, we do the can_send_now_check here
3196             hci_notify_if_sco_can_send_now();
3197 #endif
3198             break;
3199 
3200 #ifdef ENABLE_CLASSIC
3201         case HCI_EVENT_SCO_CAN_SEND_NOW:
3202             // For SCO, we do the can_send_now_check here
3203             hci_stack->sco_can_send_now = true;
3204             hci_notify_if_sco_can_send_now();
3205             return;
3206 
3207         // explode inquriy results for easier consumption
3208         case HCI_EVENT_INQUIRY_RESULT:
3209         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3210         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3211             gap_inquiry_explode(packet, size);
3212             break;
3213 #endif
3214 
3215 #ifdef ENABLE_BLE
3216         case HCI_EVENT_LE_META:
3217             switch (packet[2]){
3218 #ifdef ENABLE_LE_CENTRAL
3219                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3220                     // log_info("advertising report received");
3221                     if (!hci_stack->le_scanning_enabled) break;
3222                     le_handle_advertisement_report(packet, size);
3223                     break;
3224 #endif
3225                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3226 					event_handle_le_connection_complete(packet);
3227                     break;
3228 
3229                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3230                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3231                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3232                     conn = hci_connection_for_handle(handle);
3233                     if (!conn) break;
3234                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3235                     break;
3236 
3237                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3238                     // connection
3239                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3240                     conn = hci_connection_for_handle(handle);
3241                     if (conn) {
3242                         // read arguments
3243                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3244                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3245                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3246                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3247 
3248                         // validate against current connection parameter range
3249                         le_connection_parameter_range_t existing_range;
3250                         gap_get_connection_parameter_range(&existing_range);
3251                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3252                         if (update_parameter){
3253                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3254                             conn->le_conn_interval_min = le_conn_interval_min;
3255                             conn->le_conn_interval_max = le_conn_interval_max;
3256                             conn->le_conn_latency = le_conn_latency;
3257                             conn->le_supervision_timeout = le_supervision_timeout;
3258                         } else {
3259                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3260                         }
3261                     }
3262                     break;
3263 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3264                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3265                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3266                     conn = hci_connection_for_handle(handle);
3267                     if (conn) {
3268                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3269                     }
3270                     break;
3271 #endif
3272                 default:
3273                     break;
3274             }
3275             break;
3276 #endif
3277         case HCI_EVENT_VENDOR_SPECIFIC:
3278             // Vendor specific commands often create vendor specific event instead of num completed packets
3279             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3280             switch (hci_stack->manufacturer){
3281                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3282                     hci_stack->num_cmd_packets = 1;
3283                     break;
3284                 default:
3285                     break;
3286             }
3287             break;
3288         default:
3289             break;
3290     }
3291 
3292     handle_event_for_current_stack_state(packet, size);
3293 
3294     // notify upper stack
3295 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3296 
3297     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3298     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3299 		handle = little_endian_read_16(packet, 3);
3300 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3301 		// discard connection if app did not trigger a reconnect in the event handler
3302 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3303 			hci_shutdown_connection(aConn);
3304 		}
3305     }
3306 
3307 	// execute main loop
3308 	hci_run();
3309 }
3310 
3311 #ifdef ENABLE_CLASSIC
3312 
3313 #ifdef ENABLE_SCO_OVER_HCI
3314 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3315 static void sco_schedule_tx(hci_connection_t * conn);
3316 
3317 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3318     log_debug("SCO TX Timeout");
3319     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3320     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3321     if (!conn) return;
3322 
3323     // trigger send
3324     conn->sco_tx_ready = 1;
3325     // extra packet if CVSD but SCO buffer is too short
3326     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3327         conn->sco_tx_ready++;
3328     }
3329     hci_notify_if_sco_can_send_now();
3330 }
3331 
3332 
3333 #define SCO_TX_AFTER_RX_MS (6)
3334 
3335 static void sco_schedule_tx(hci_connection_t * conn){
3336 
3337     uint32_t now = btstack_run_loop_get_time_ms();
3338     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3339     int time_delta_ms = sco_tx_ms - now;
3340 
3341     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3342 
3343     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3344     btstack_run_loop_remove_timer(timer);
3345     btstack_run_loop_set_timer(timer, time_delta_ms);
3346     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3347     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3348     btstack_run_loop_add_timer(timer);
3349 }
3350 #endif
3351 
3352 static void sco_handler(uint8_t * packet, uint16_t size){
3353     // lookup connection struct
3354     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3355     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3356     if (!conn) return;
3357 
3358 #ifdef ENABLE_SCO_OVER_HCI
3359     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3360     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3361         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3362             packet[2] = 0x3c;
3363             memmove(&packet[3], &packet[23], 63);
3364             size = 63;
3365         }
3366     }
3367 
3368     if (hci_have_usb_transport()){
3369         // Nothing to do
3370     } else {
3371         // 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);
3372         if (hci_stack->synchronous_flow_control_enabled == 0){
3373             uint32_t now = btstack_run_loop_get_time_ms();
3374 
3375             if (!conn->sco_rx_valid){
3376                 // ignore first 10 packets
3377                 conn->sco_rx_count++;
3378                 // log_debug("sco rx count %u", conn->sco_rx_count);
3379                 if (conn->sco_rx_count == 10) {
3380                     // use first timestamp as is and pretent it just started
3381                     conn->sco_rx_ms = now;
3382                     conn->sco_rx_valid = 1;
3383                     conn->sco_rx_count = 0;
3384                     sco_schedule_tx(conn);
3385                 }
3386             } else {
3387                 // track expected arrival timme
3388                 conn->sco_rx_count++;
3389                 conn->sco_rx_ms += 7;
3390                 int delta = (int32_t) (now - conn->sco_rx_ms);
3391                 if (delta > 0){
3392                     conn->sco_rx_ms++;
3393                 }
3394                 // log_debug("sco rx %u", conn->sco_rx_ms);
3395                 sco_schedule_tx(conn);
3396             }
3397         }
3398     }
3399 #endif
3400 
3401     // deliver to app
3402     if (hci_stack->sco_packet_handler) {
3403         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3404     }
3405 
3406 #ifdef HAVE_SCO_TRANSPORT
3407     // We can send one packet for each received packet
3408     conn->sco_tx_ready++;
3409     hci_notify_if_sco_can_send_now();
3410 #endif
3411 
3412 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3413     conn->num_packets_completed++;
3414     hci_stack->host_completed_packets = 1;
3415     hci_run();
3416 #endif
3417 }
3418 #endif
3419 
3420 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3421     hci_dump_packet(packet_type, 1, packet, size);
3422     switch (packet_type) {
3423         case HCI_EVENT_PACKET:
3424             event_handler(packet, size);
3425             break;
3426         case HCI_ACL_DATA_PACKET:
3427             acl_handler(packet, size);
3428             break;
3429 #ifdef ENABLE_CLASSIC
3430         case HCI_SCO_DATA_PACKET:
3431             sco_handler(packet, size);
3432             break;
3433 #endif
3434         default:
3435             break;
3436     }
3437 }
3438 
3439 /**
3440  * @brief Add event packet handler.
3441  */
3442 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3443     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3444 }
3445 
3446 
3447 /** Register HCI packet handlers */
3448 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3449     hci_stack->acl_packet_handler = handler;
3450 }
3451 
3452 #ifdef ENABLE_CLASSIC
3453 /**
3454  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3455  */
3456 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3457     hci_stack->sco_packet_handler = handler;
3458 }
3459 #endif
3460 
3461 static void hci_state_reset(void){
3462     // no connections yet
3463     hci_stack->connections = NULL;
3464 
3465     // keep discoverable/connectable as this has been requested by the client(s)
3466     // hci_stack->discoverable = 0;
3467     // hci_stack->connectable = 0;
3468     // hci_stack->bondable = 1;
3469     // hci_stack->own_addr_type = 0;
3470 
3471     // buffer is free
3472     hci_stack->hci_packet_buffer_reserved = false;
3473 
3474     // no pending cmds
3475     hci_stack->decline_reason = 0;
3476 
3477     hci_stack->secure_connections_active = false;
3478 
3479 #ifdef ENABLE_CLASSIC
3480     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3481     hci_stack->gap_tasks =
3482             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3483             GAP_TASK_SET_CLASS_OF_DEVICE |
3484             GAP_TASK_SET_LOCAL_NAME |
3485             GAP_TASK_SET_EIR_DATA |
3486             GAP_TASK_WRITE_SCAN_ENABLE;
3487 #endif
3488 
3489 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3490     hci_stack->classic_read_local_oob_data = true;
3491     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3492 #endif
3493 
3494     // LE
3495 #ifdef ENABLE_BLE
3496     memset(hci_stack->le_random_address, 0, 6);
3497     hci_stack->le_random_address_set = 0;
3498 #endif
3499 #ifdef ENABLE_LE_CENTRAL
3500     hci_stack->le_scanning_active  = false;
3501     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3502     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3503     hci_stack->le_whitelist_capacity = 0;
3504 #endif
3505 #ifdef ENABLE_LE_PERIPHERAL
3506     hci_stack->le_advertisements_active = false;
3507     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3508         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3509     }
3510     if (hci_stack->le_advertisements_data != NULL){
3511         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3512     }
3513 #endif
3514 }
3515 
3516 #ifdef ENABLE_CLASSIC
3517 /**
3518  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3519  */
3520 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3521     // store and open remote device db
3522     hci_stack->link_key_db = link_key_db;
3523     if (hci_stack->link_key_db) {
3524         hci_stack->link_key_db->open();
3525     }
3526 }
3527 #endif
3528 
3529 void hci_init(const hci_transport_t *transport, const void *config){
3530 
3531 #ifdef HAVE_MALLOC
3532     if (!hci_stack) {
3533         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3534     }
3535 #else
3536     hci_stack = &hci_stack_static;
3537 #endif
3538     memset(hci_stack, 0, sizeof(hci_stack_t));
3539 
3540     // reference to use transport layer implementation
3541     hci_stack->hci_transport = transport;
3542 
3543     // reference to used config
3544     hci_stack->config = config;
3545 
3546     // setup pointer for outgoing packet buffer
3547     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3548 
3549     // max acl payload size defined in config.h
3550     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3551 
3552     // register packet handlers with transport
3553     transport->register_packet_handler(&packet_handler);
3554 
3555     hci_stack->state = HCI_STATE_OFF;
3556 
3557     // class of device
3558     hci_stack->class_of_device = 0x007a020c; // Smartphone
3559 
3560     // bondable by default
3561     hci_stack->bondable = 1;
3562 
3563 #ifdef ENABLE_CLASSIC
3564     // classic name
3565     hci_stack->local_name = default_classic_name;
3566 
3567     // Master slave policy
3568     hci_stack->master_slave_policy = 1;
3569 
3570     // Allow Role Switch
3571     hci_stack->allow_role_switch = 1;
3572 
3573     // Default / minimum security level = 2
3574     hci_stack->gap_security_level = LEVEL_2;
3575 
3576     // Default Security Mode 4
3577     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3578 
3579     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3580     hci_stack->gap_required_encyrption_key_size = 7;
3581 
3582     // Link Supervision Timeout
3583     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3584 
3585 #endif
3586 
3587     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3588     hci_stack->ssp_enable = 1;
3589     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3590     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3591     hci_stack->ssp_auto_accept = 1;
3592 
3593     // Secure Connections: enable (requires support from Controller)
3594     hci_stack->secure_connections_enable = true;
3595 
3596     // voice setting - signed 16 bit pcm data with CVSD over the air
3597     hci_stack->sco_voice_setting = 0x60;
3598 
3599 #ifdef ENABLE_LE_CENTRAL
3600     // connection parameter to use for outgoing connections
3601     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3602     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3603     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3604     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3605     hci_stack->le_connection_latency      = 4;         // 4
3606     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3607     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3608     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3609 
3610     // default LE Scanning
3611     hci_stack->le_scan_type     =   0x1; // active
3612     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3613     hci_stack->le_scan_window   =  0x30; //  30 ms
3614 #endif
3615 
3616 #ifdef ENABLE_LE_PERIPHERAL
3617     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3618 #endif
3619 
3620     // connection parameter range used to answer connection parameter update requests in l2cap
3621     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3622     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3623     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3624     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3625     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3626     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3627 
3628     hci_state_reset();
3629 }
3630 
3631 void hci_deinit(void){
3632 #ifdef HAVE_MALLOC
3633     if (hci_stack) {
3634         free(hci_stack);
3635     }
3636 #endif
3637     hci_stack = NULL;
3638 
3639 #ifdef ENABLE_CLASSIC
3640     disable_l2cap_timeouts = 0;
3641 #endif
3642 }
3643 
3644 /**
3645  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3646  */
3647 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3648     hci_stack->chipset = chipset_driver;
3649 
3650     // reset chipset driver - init is also called on power_up
3651     if (hci_stack->chipset && hci_stack->chipset->init){
3652         hci_stack->chipset->init(hci_stack->config);
3653     }
3654 }
3655 
3656 /**
3657  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3658  */
3659 void hci_set_control(const btstack_control_t *hardware_control){
3660     // references to used control implementation
3661     hci_stack->control = hardware_control;
3662     // init with transport config
3663     hardware_control->init(hci_stack->config);
3664 }
3665 
3666 void hci_close(void){
3667 
3668 #ifdef ENABLE_CLASSIC
3669     // close remote device db
3670     if (hci_stack->link_key_db) {
3671         hci_stack->link_key_db->close();
3672     }
3673 #endif
3674 
3675     btstack_linked_list_iterator_t lit;
3676     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3677     while (btstack_linked_list_iterator_has_next(&lit)){
3678         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3679         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3680         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3681         hci_shutdown_connection(connection);
3682     }
3683 
3684     hci_power_control(HCI_POWER_OFF);
3685 
3686 #ifdef HAVE_MALLOC
3687     free(hci_stack);
3688 #endif
3689     hci_stack = NULL;
3690 }
3691 
3692 #ifdef HAVE_SCO_TRANSPORT
3693 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3694     hci_stack->sco_transport = sco_transport;
3695     sco_transport->register_packet_handler(&packet_handler);
3696 }
3697 #endif
3698 
3699 #ifdef ENABLE_CLASSIC
3700 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3701     // validate ranage and set
3702     if (encryption_key_size < 7)  return;
3703     if (encryption_key_size > 16) return;
3704     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3705 }
3706 
3707 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3708     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3709         hci_stack->gap_security_mode = security_mode;
3710         return ERROR_CODE_SUCCESS;
3711     } else {
3712         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3713     }
3714 }
3715 
3716 gap_security_mode_t gap_get_security_mode(void){
3717     return hci_stack->gap_security_mode;
3718 }
3719 
3720 void gap_set_security_level(gap_security_level_t security_level){
3721     hci_stack->gap_security_level = security_level;
3722 }
3723 
3724 gap_security_level_t gap_get_security_level(void){
3725     if (hci_stack->gap_secure_connections_only_mode){
3726         return LEVEL_4;
3727     }
3728     return hci_stack->gap_security_level;
3729 }
3730 
3731 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3732     hci_stack->gap_minimal_service_security_level = security_level;
3733 }
3734 
3735 void gap_set_secure_connections_only_mode(bool enable){
3736     hci_stack->gap_secure_connections_only_mode = enable;
3737 }
3738 
3739 bool gap_get_secure_connections_only_mode(void){
3740     return hci_stack->gap_secure_connections_only_mode;
3741 }
3742 #endif
3743 
3744 #ifdef ENABLE_CLASSIC
3745 void gap_set_class_of_device(uint32_t class_of_device){
3746     hci_stack->class_of_device = class_of_device;
3747     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3748     hci_run();
3749 }
3750 
3751 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3752     hci_stack->default_link_policy_settings = default_link_policy_settings;
3753     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3754     hci_run();
3755 }
3756 
3757 void gap_set_allow_role_switch(bool allow_role_switch){
3758     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3759 }
3760 
3761 uint8_t hci_get_allow_role_switch(void){
3762     return  hci_stack->allow_role_switch;
3763 }
3764 
3765 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3766     hci_stack->link_supervision_timeout = link_supervision_timeout;
3767 }
3768 
3769 void hci_disable_l2cap_timeout_check(void){
3770     disable_l2cap_timeouts = 1;
3771 }
3772 #endif
3773 
3774 #ifndef HAVE_HOST_CONTROLLER_API
3775 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3776 void hci_set_bd_addr(bd_addr_t addr){
3777     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3778     hci_stack->custom_bd_addr_set = 1;
3779 }
3780 #endif
3781 
3782 // State-Module-Driver overview
3783 // state                    module  low-level
3784 // HCI_STATE_OFF             off      close
3785 // HCI_STATE_INITIALIZING,   on       open
3786 // HCI_STATE_WORKING,        on       open
3787 // HCI_STATE_HALTING,        on       open
3788 // HCI_STATE_SLEEPING,    off/sleep   close
3789 // HCI_STATE_FALLING_ASLEEP  on       open
3790 
3791 static int hci_power_control_on(void){
3792 
3793     // power on
3794     int err = 0;
3795     if (hci_stack->control && hci_stack->control->on){
3796         err = (*hci_stack->control->on)();
3797     }
3798     if (err){
3799         log_error( "POWER_ON failed");
3800         hci_emit_hci_open_failed();
3801         return err;
3802     }
3803 
3804     // int chipset driver
3805     if (hci_stack->chipset && hci_stack->chipset->init){
3806         hci_stack->chipset->init(hci_stack->config);
3807     }
3808 
3809     // init transport
3810     if (hci_stack->hci_transport->init){
3811         hci_stack->hci_transport->init(hci_stack->config);
3812     }
3813 
3814     // open transport
3815     err = hci_stack->hci_transport->open();
3816     if (err){
3817         log_error( "HCI_INIT failed, turning Bluetooth off again");
3818         if (hci_stack->control && hci_stack->control->off){
3819             (*hci_stack->control->off)();
3820         }
3821         hci_emit_hci_open_failed();
3822         return err;
3823     }
3824     return 0;
3825 }
3826 
3827 static void hci_power_control_off(void){
3828 
3829     log_info("hci_power_control_off");
3830 
3831     // close low-level device
3832     hci_stack->hci_transport->close();
3833 
3834     log_info("hci_power_control_off - hci_transport closed");
3835 
3836     // power off
3837     if (hci_stack->control && hci_stack->control->off){
3838         (*hci_stack->control->off)();
3839     }
3840 
3841     log_info("hci_power_control_off - control closed");
3842 
3843     hci_stack->state = HCI_STATE_OFF;
3844 }
3845 
3846 static void hci_power_control_sleep(void){
3847 
3848     log_info("hci_power_control_sleep");
3849 
3850 #if 0
3851     // don't close serial port during sleep
3852 
3853     // close low-level device
3854     hci_stack->hci_transport->close(hci_stack->config);
3855 #endif
3856 
3857     // sleep mode
3858     if (hci_stack->control && hci_stack->control->sleep){
3859         (*hci_stack->control->sleep)();
3860     }
3861 
3862     hci_stack->state = HCI_STATE_SLEEPING;
3863 }
3864 
3865 static int hci_power_control_wake(void){
3866 
3867     log_info("hci_power_control_wake");
3868 
3869     // wake on
3870     if (hci_stack->control && hci_stack->control->wake){
3871         (*hci_stack->control->wake)();
3872     }
3873 
3874 #if 0
3875     // open low-level device
3876     int err = hci_stack->hci_transport->open(hci_stack->config);
3877     if (err){
3878         log_error( "HCI_INIT failed, turning Bluetooth off again");
3879         if (hci_stack->control && hci_stack->control->off){
3880             (*hci_stack->control->off)();
3881         }
3882         hci_emit_hci_open_failed();
3883         return err;
3884     }
3885 #endif
3886 
3887     return 0;
3888 }
3889 
3890 static void hci_power_transition_to_initializing(void){
3891     // set up state machine
3892     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3893     hci_stack->hci_packet_buffer_reserved = false;
3894     hci_stack->state = HCI_STATE_INITIALIZING;
3895     hci_stack->substate = HCI_INIT_SEND_RESET;
3896 }
3897 
3898 // returns error
3899 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3900     int err;
3901     switch (power_mode){
3902         case HCI_POWER_ON:
3903             err = hci_power_control_on();
3904             if (err != 0) {
3905                 log_error("hci_power_control_on() error %d", err);
3906                 return err;
3907             }
3908             hci_power_transition_to_initializing();
3909             break;
3910         case HCI_POWER_OFF:
3911             // do nothing
3912             break;
3913         case HCI_POWER_SLEEP:
3914             // do nothing (with SLEEP == OFF)
3915             break;
3916         default:
3917             btstack_assert(false);
3918             break;
3919     }
3920     return ERROR_CODE_SUCCESS;
3921 }
3922 
3923 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3924     switch (power_mode){
3925         case HCI_POWER_ON:
3926             // do nothing
3927             break;
3928         case HCI_POWER_OFF:
3929             // no connections yet, just turn it off
3930             hci_power_control_off();
3931             break;
3932         case HCI_POWER_SLEEP:
3933             // no connections yet, just turn it off
3934             hci_power_control_sleep();
3935             break;
3936         default:
3937             btstack_assert(false);
3938             break;
3939     }
3940     return ERROR_CODE_SUCCESS;
3941 }
3942 
3943 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3944     switch (power_mode){
3945         case HCI_POWER_ON:
3946             // do nothing
3947             break;
3948         case HCI_POWER_OFF:
3949             // see hci_run
3950             hci_stack->state = HCI_STATE_HALTING;
3951             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3952             break;
3953         case HCI_POWER_SLEEP:
3954             // see hci_run
3955             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3956             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3957             break;
3958         default:
3959             btstack_assert(false);
3960             break;
3961     }
3962     return ERROR_CODE_SUCCESS;
3963 }
3964 
3965 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3966     switch (power_mode){
3967         case HCI_POWER_ON:
3968             hci_power_transition_to_initializing();
3969             break;
3970         case HCI_POWER_OFF:
3971             // do nothing
3972             break;
3973         case HCI_POWER_SLEEP:
3974             // see hci_run
3975             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3976             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3977             break;
3978         default:
3979             btstack_assert(false);
3980             break;
3981     }
3982     return ERROR_CODE_SUCCESS;
3983 }
3984 
3985 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3986     switch (power_mode){
3987         case HCI_POWER_ON:
3988             hci_power_transition_to_initializing();
3989             break;
3990         case HCI_POWER_OFF:
3991             // see hci_run
3992             hci_stack->state = HCI_STATE_HALTING;
3993             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3994             break;
3995         case HCI_POWER_SLEEP:
3996             // do nothing
3997             break;
3998         default:
3999             btstack_assert(false);
4000             break;
4001     }
4002     return ERROR_CODE_SUCCESS;
4003 }
4004 
4005 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
4006     int err;
4007     switch (power_mode){
4008         case HCI_POWER_ON:
4009             err = hci_power_control_wake();
4010             if (err) return err;
4011             hci_power_transition_to_initializing();
4012             break;
4013         case HCI_POWER_OFF:
4014             hci_stack->state = HCI_STATE_HALTING;
4015             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
4016             break;
4017         case HCI_POWER_SLEEP:
4018             // do nothing
4019             break;
4020         default:
4021             btstack_assert(false);
4022             break;
4023     }
4024     return ERROR_CODE_SUCCESS;
4025 }
4026 
4027 int hci_power_control(HCI_POWER_MODE power_mode){
4028     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4029     int err = 0;
4030     switch (hci_stack->state){
4031         case HCI_STATE_OFF:
4032             err = hci_power_control_state_off(power_mode);
4033             break;
4034         case HCI_STATE_INITIALIZING:
4035             err = hci_power_control_state_initializing(power_mode);
4036             break;
4037         case HCI_STATE_WORKING:
4038             err = hci_power_control_state_working(power_mode);
4039             break;
4040         case HCI_STATE_HALTING:
4041             err = hci_power_control_state_halting(power_mode);
4042             break;
4043         case HCI_STATE_FALLING_ASLEEP:
4044             err = hci_power_control_state_falling_asleep(power_mode);
4045             break;
4046         case HCI_STATE_SLEEPING:
4047             err = hci_power_control_state_sleeping(power_mode);
4048             break;
4049         default:
4050             btstack_assert(false);
4051             break;
4052     }
4053     if (err != 0){
4054         return err;
4055     }
4056 
4057     // create internal event
4058 	hci_emit_state();
4059 
4060 	// trigger next/first action
4061 	hci_run();
4062 
4063     return 0;
4064 }
4065 
4066 
4067 #ifdef ENABLE_CLASSIC
4068 
4069 static void hci_update_scan_enable(void){
4070     // 2 = page scan, 1 = inq scan
4071     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4072     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4073     hci_run();
4074 }
4075 
4076 void gap_discoverable_control(uint8_t enable){
4077     if (enable) enable = 1; // normalize argument
4078 
4079     if (hci_stack->discoverable == enable){
4080         hci_emit_discoverable_enabled(hci_stack->discoverable);
4081         return;
4082     }
4083 
4084     hci_stack->discoverable = enable;
4085     hci_update_scan_enable();
4086 }
4087 
4088 void gap_connectable_control(uint8_t enable){
4089     if (enable) enable = 1; // normalize argument
4090 
4091     // don't emit event
4092     if (hci_stack->connectable == enable) return;
4093 
4094     hci_stack->connectable = enable;
4095     hci_update_scan_enable();
4096 }
4097 #endif
4098 
4099 void gap_local_bd_addr(bd_addr_t address_buffer){
4100     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4101 }
4102 
4103 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4104 static void hci_host_num_completed_packets(void){
4105 
4106     // create packet manually as arrays are not supported and num_commands should not get reduced
4107     hci_reserve_packet_buffer();
4108     uint8_t * packet = hci_get_outgoing_packet_buffer();
4109 
4110     uint16_t size = 0;
4111     uint16_t num_handles = 0;
4112     packet[size++] = 0x35;
4113     packet[size++] = 0x0c;
4114     size++;  // skip param len
4115     size++;  // skip num handles
4116 
4117     // add { handle, packets } entries
4118     btstack_linked_item_t * it;
4119     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4120         hci_connection_t * connection = (hci_connection_t *) it;
4121         if (connection->num_packets_completed){
4122             little_endian_store_16(packet, size, connection->con_handle);
4123             size += 2;
4124             little_endian_store_16(packet, size, connection->num_packets_completed);
4125             size += 2;
4126             //
4127             num_handles++;
4128             connection->num_packets_completed = 0;
4129         }
4130     }
4131 
4132     packet[2] = size - 3;
4133     packet[3] = num_handles;
4134 
4135     hci_stack->host_completed_packets = 0;
4136 
4137     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4138     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4139 
4140     // release packet buffer for synchronous transport implementations
4141     if (hci_transport_synchronous()){
4142         hci_release_packet_buffer();
4143         hci_emit_transport_packet_sent();
4144     }
4145 }
4146 #endif
4147 
4148 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4149     UNUSED(ds);
4150     hci_stack->substate = HCI_HALTING_CLOSE;
4151     // allow packet handlers to defer final shutdown
4152     hci_emit_state();
4153     hci_run();
4154 }
4155 
4156 static bool hci_run_acl_fragments(void){
4157     if (hci_stack->acl_fragmentation_total_size > 0u) {
4158         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4159         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4160         if (connection) {
4161             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4162                 hci_send_acl_packet_fragments(connection);
4163                 return true;
4164             }
4165         } else {
4166             // connection gone -> discard further fragments
4167             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4168             hci_stack->acl_fragmentation_total_size = 0;
4169             hci_stack->acl_fragmentation_pos = 0;
4170         }
4171     }
4172     return false;
4173 }
4174 
4175 #ifdef ENABLE_CLASSIC
4176 static bool hci_run_general_gap_classic(void){
4177 
4178     // assert stack is working and classic is active
4179     if (hci_classic_supported() == false)      return false;
4180     if (hci_stack->state != HCI_STATE_WORKING) return false;
4181 
4182     // decline incoming connections
4183     if (hci_stack->decline_reason){
4184         uint8_t reason = hci_stack->decline_reason;
4185         hci_stack->decline_reason = 0;
4186         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4187         return true;
4188     }
4189 
4190     if (hci_stack->gap_tasks != 0){
4191         hci_run_gap_tasks_classic();
4192         return true;
4193     }
4194 
4195     // start/stop inquiry
4196     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4197         uint8_t duration = hci_stack->inquiry_state;
4198         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4199         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4200         return true;
4201     }
4202     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4203         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4204         hci_send_cmd(&hci_inquiry_cancel);
4205         return true;
4206     }
4207     // remote name request
4208     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4209         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4210         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4211                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4212         return true;
4213     }
4214 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4215     // Local OOB data
4216     if (hci_stack->classic_read_local_oob_data){
4217         hci_stack->classic_read_local_oob_data = false;
4218         if (hci_stack->local_supported_commands[1] & 0x10u){
4219             hci_send_cmd(&hci_read_local_extended_oob_data);
4220         } else {
4221             hci_send_cmd(&hci_read_local_oob_data);
4222         }
4223     }
4224 #endif
4225     // pairing
4226     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4227         uint8_t state = hci_stack->gap_pairing_state;
4228         uint8_t pin_code[16];
4229         switch (state){
4230             case GAP_PAIRING_STATE_SEND_PIN:
4231                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4232                 memset(pin_code, 0, 16);
4233                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4234                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4235                 break;
4236             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4237                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4238                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4239                 break;
4240             case GAP_PAIRING_STATE_SEND_PASSKEY:
4241                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4242                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4243                 break;
4244             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4245                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4246                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4247                 break;
4248             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4249                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4250                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4251                 break;
4252             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4253                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4254                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4255                 break;
4256             default:
4257                 break;
4258         }
4259         return true;
4260     }
4261     return false;
4262 }
4263 #endif
4264 
4265 #ifdef ENABLE_BLE
4266 static bool hci_run_general_gap_le(void){
4267 
4268     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4269 
4270     if (hci_stack->state != HCI_STATE_WORKING) return false;
4271     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4272 
4273 
4274     // Phase 1: collect what to stop
4275 
4276     bool scanning_stop = false;
4277     bool connecting_stop = false;
4278     bool advertising_stop = false;
4279 
4280 #ifndef ENABLE_LE_CENTRAL
4281     UNUSED(scanning_stop);
4282     UNUSED(connecting_stop);
4283 #endif
4284 #ifndef ENABLE_LE_PERIPHERAL
4285     UNUSED(advertising_stop);
4286 #endif
4287 
4288     // check if whitelist needs modification
4289     bool whitelist_modification_pending = false;
4290     btstack_linked_list_iterator_t lit;
4291     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4292     while (btstack_linked_list_iterator_has_next(&lit)){
4293         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4294         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4295             whitelist_modification_pending = true;
4296             break;
4297         }
4298     }
4299     // check if resolving list needs modification
4300     bool resolving_list_modification_pending = false;
4301 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4302     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4303 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4304         resolving_list_modification_pending = true;
4305     }
4306 #endif
4307 
4308 #ifdef ENABLE_LE_CENTRAL
4309     // scanning control
4310     if (hci_stack->le_scanning_active) {
4311         // stop if:
4312         // - parameter change required
4313         // - it's disabled
4314         // - whitelist change required but used for scanning
4315         // - resolving list modified
4316         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4317         if ((hci_stack->le_scanning_param_update) ||
4318             !hci_stack->le_scanning_enabled ||
4319             scanning_uses_whitelist ||
4320             resolving_list_modification_pending){
4321 
4322             scanning_stop = true;
4323         }
4324     }
4325 #endif
4326 
4327 #ifdef ENABLE_LE_CENTRAL
4328     // connecting control
4329     bool connecting_with_whitelist;
4330     switch (hci_stack->le_connecting_state){
4331         case LE_CONNECTING_DIRECT:
4332         case LE_CONNECTING_WHITELIST:
4333             // stop connecting if:
4334             // - connecting uses white and whitelist modification pending
4335             // - if it got disabled
4336             // - resolving list modified
4337             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4338             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4339                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4340                 resolving_list_modification_pending) {
4341 
4342                 connecting_stop = true;
4343             }
4344             break;
4345         default:
4346             break;
4347     }
4348 #endif
4349 
4350 #ifdef ENABLE_LE_PERIPHERAL
4351     // le advertisement control
4352     if (hci_stack->le_advertisements_active){
4353         // stop if:
4354         // - parameter change required
4355         // - it's disabled
4356         // - whitelist change required but used for advertisement filter policy
4357         // - resolving list modified
4358         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4359         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4360         if (advertising_change ||
4361             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4362             (advertising_uses_whitelist & whitelist_modification_pending) ||
4363             resolving_list_modification_pending) {
4364 
4365             advertising_stop = true;
4366         }
4367     }
4368 #endif
4369 
4370 
4371     // Phase 2: stop everything that should be off during modifications
4372 
4373 #ifdef ENABLE_LE_CENTRAL
4374     if (scanning_stop){
4375         hci_stack->le_scanning_active = false;
4376         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4377         return true;
4378     }
4379 #endif
4380 
4381 #ifdef ENABLE_LE_CENTRAL
4382     if (connecting_stop){
4383         hci_send_cmd(&hci_le_create_connection_cancel);
4384         return true;
4385     }
4386 #endif
4387 
4388 #ifdef ENABLE_LE_PERIPHERAL
4389     if (advertising_stop){
4390         hci_stack->le_advertisements_active = false;
4391         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4392         return true;
4393     }
4394 #endif
4395 
4396     // Phase 3: modify
4397 
4398 #ifdef ENABLE_LE_CENTRAL
4399     if (hci_stack->le_scanning_param_update){
4400         hci_stack->le_scanning_param_update = false;
4401         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4402                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4403         return true;
4404     }
4405 #endif
4406 
4407 #ifdef ENABLE_LE_PERIPHERAL
4408     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4409         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4410         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4411         hci_send_cmd(&hci_le_set_advertising_parameters,
4412                      hci_stack->le_advertisements_interval_min,
4413                      hci_stack->le_advertisements_interval_max,
4414                      hci_stack->le_advertisements_type,
4415                      hci_stack->le_advertisements_own_addr_type,
4416                      hci_stack->le_advertisements_direct_address_type,
4417                      hci_stack->le_advertisements_direct_address,
4418                      hci_stack->le_advertisements_channel_map,
4419                      hci_stack->le_advertisements_filter_policy);
4420         return true;
4421     }
4422     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4423         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4424         uint8_t adv_data_clean[31];
4425         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4426         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4427                      hci_stack->le_advertisements_data_len);
4428         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4429         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4430         return true;
4431     }
4432     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4433         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4434         uint8_t scan_data_clean[31];
4435         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4436         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4437                      hci_stack->le_scan_response_data_len);
4438         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4439         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4440         return true;
4441     }
4442 #endif
4443 
4444 
4445 #ifdef ENABLE_LE_CENTRAL
4446     // if connect with whitelist was active and is not cancelled yet, wait until next time
4447     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4448 #endif
4449 
4450     // LE Whitelist Management
4451     if (whitelist_modification_pending){
4452         // add/remove entries
4453         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4454         while (btstack_linked_list_iterator_has_next(&lit)){
4455             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4456 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4457 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4458 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4459 				return true;
4460 			}
4461             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4462 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4463                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4464                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4465                 return true;
4466             }
4467             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4468 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4469 				btstack_memory_whitelist_entry_free(entry);
4470             }
4471         }
4472     }
4473 
4474 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4475     // LE Resolving List Management
4476     if (resolving_list_supported) {
4477 		uint16_t i;
4478 		switch (hci_stack->le_resolving_list_state) {
4479 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4480 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4481 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4482 				return true;
4483 			case LE_RESOLVING_LIST_READ_SIZE:
4484 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4485 				hci_send_cmd(&hci_le_read_resolving_list_size);
4486 				return true;
4487 			case LE_RESOLVING_LIST_SEND_CLEAR:
4488 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4489 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4490 							  sizeof(hci_stack->le_resolving_list_add_entries));
4491 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4492 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4493 				hci_send_cmd(&hci_le_clear_resolving_list);
4494 				return true;
4495 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4496 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4497 					uint8_t offset = i >> 3;
4498 					uint8_t mask = 1 << (i & 7);
4499 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4500 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4501 					bd_addr_t peer_identity_addreses;
4502 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4503 					sm_key_t peer_irk;
4504 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4505 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4506 
4507 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4508 					// trigger whitelist entry 'update' (work around for controller bug)
4509 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4510 					while (btstack_linked_list_iterator_has_next(&lit)) {
4511 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4512 						if (entry->address_type != peer_identity_addr_type) continue;
4513 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4514 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4515 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4516 					}
4517 #endif
4518 
4519 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4520 								 peer_identity_addreses);
4521 					return true;
4522 				}
4523 
4524 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4525 
4526 				/* fall through */
4527 
4528 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4529 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4530 					uint8_t offset = i >> 3;
4531 					uint8_t mask = 1 << (i & 7);
4532 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4533 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4534 					bd_addr_t peer_identity_addreses;
4535 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4536 					sm_key_t peer_irk;
4537 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4538 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4539 					const uint8_t *local_irk = gap_get_persistent_irk();
4540 					// command uses format specifier 'P' that stores 16-byte value without flip
4541 					uint8_t local_irk_flipped[16];
4542 					uint8_t peer_irk_flipped[16];
4543 					reverse_128(local_irk, local_irk_flipped);
4544 					reverse_128(peer_irk, peer_irk_flipped);
4545 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4546 								 peer_irk_flipped, local_irk_flipped);
4547 					return true;
4548 				}
4549 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4550 				break;
4551 
4552 			default:
4553 				break;
4554 		}
4555 	}
4556     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4557 #endif
4558 
4559     // Phase 4: restore state
4560 
4561 #ifdef ENABLE_LE_CENTRAL
4562     // re-start scanning
4563     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4564         hci_stack->le_scanning_active = true;
4565         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4566         return true;
4567     }
4568 #endif
4569 
4570 #ifdef ENABLE_LE_CENTRAL
4571     // re-start connecting
4572     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4573         bd_addr_t null_addr;
4574         memset(null_addr, 0, 6);
4575         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4576         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4577         hci_send_cmd(&hci_le_create_connection,
4578                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4579                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4580                      1,         // use whitelist
4581                      0,         // peer address type
4582                      null_addr, // peer bd addr
4583                      hci_stack->le_connection_own_addr_type,   // our addr type:
4584                      hci_stack->le_connection_interval_min,    // conn interval min
4585                      hci_stack->le_connection_interval_max,    // conn interval max
4586                      hci_stack->le_connection_latency,         // conn latency
4587                      hci_stack->le_supervision_timeout,        // conn latency
4588                      hci_stack->le_minimum_ce_length,          // min ce length
4589                      hci_stack->le_maximum_ce_length           // max ce length
4590         );
4591         return true;
4592     }
4593 #endif
4594 
4595 #ifdef ENABLE_LE_PERIPHERAL
4596     // re-start advertising
4597     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4598         // check if advertisements should be enabled given
4599         hci_stack->le_advertisements_active = true;
4600         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4601         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4602         return true;
4603     }
4604 #endif
4605 
4606     return false;
4607 }
4608 #endif
4609 
4610 static bool hci_run_general_pending_commands(void){
4611     btstack_linked_item_t * it;
4612     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4613         hci_connection_t * connection = (hci_connection_t *) it;
4614 
4615         switch(connection->state){
4616             case SEND_CREATE_CONNECTION:
4617                 switch(connection->address_type){
4618 #ifdef ENABLE_CLASSIC
4619                     case BD_ADDR_TYPE_ACL:
4620                         log_info("sending hci_create_connection");
4621                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4622                         break;
4623 #endif
4624                     default:
4625 #ifdef ENABLE_BLE
4626 #ifdef ENABLE_LE_CENTRAL
4627                         log_info("sending hci_le_create_connection");
4628                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4629                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4630                         hci_send_cmd(&hci_le_create_connection,
4631                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4632                                      hci_stack->le_connection_scan_window,      // conn scan windows
4633                                      0,         // don't use whitelist
4634                                      connection->address_type, // peer address type
4635                                      connection->address,      // peer bd addr
4636                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4637                                      hci_stack->le_connection_interval_min,    // conn interval min
4638                                      hci_stack->le_connection_interval_max,    // conn interval max
4639                                      hci_stack->le_connection_latency,         // conn latency
4640                                      hci_stack->le_supervision_timeout,        // conn latency
4641                                      hci_stack->le_minimum_ce_length,          // min ce length
4642                                      hci_stack->le_maximum_ce_length          // max ce length
4643                         );
4644                         connection->state = SENT_CREATE_CONNECTION;
4645 #endif
4646 #endif
4647                         break;
4648                 }
4649                 return true;
4650 
4651 #ifdef ENABLE_CLASSIC
4652             case RECEIVED_CONNECTION_REQUEST:
4653                 connection->role  = HCI_ROLE_SLAVE;
4654                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4655                     log_info("sending hci_accept_connection_request");
4656                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4657                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4658                 }
4659                 return true;
4660 #endif
4661 
4662 #ifdef ENABLE_BLE
4663 #ifdef ENABLE_LE_CENTRAL
4664             case SEND_CANCEL_CONNECTION:
4665                 connection->state = SENT_CANCEL_CONNECTION;
4666                 hci_send_cmd(&hci_le_create_connection_cancel);
4667                 return true;
4668 #endif
4669 #endif
4670             case SEND_DISCONNECT:
4671                 connection->state = SENT_DISCONNECT;
4672                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4673                 return true;
4674 
4675             default:
4676                 break;
4677         }
4678 
4679         // no further commands if connection is about to get shut down
4680         if (connection->state == SENT_DISCONNECT) continue;
4681 
4682         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4683             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4684             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4685             return true;
4686         }
4687 
4688 #ifdef ENABLE_CLASSIC
4689 
4690         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4691             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4692             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4693             return true;
4694         }
4695 
4696         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4697             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4698             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4699             return true;
4700         }
4701 
4702         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4703             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4704             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4705             return true;
4706         }
4707 
4708         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4709             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4710             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4711             return true;
4712         }
4713 
4714         // Handling link key request requires remote supported features
4715         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4716             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4717             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4718 
4719             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4720             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4721             if (have_link_key && security_level_sufficient){
4722                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4723             } else {
4724                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4725             }
4726             return true;
4727         }
4728 
4729         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4730             log_info("denying to pin request");
4731             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4732             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4733             return true;
4734         }
4735 
4736         // security assessment requires remote features
4737         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4738             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4739             hci_ssp_assess_security_on_io_cap_request(connection);
4740             // 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
4741         }
4742 
4743         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4744             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4745             // set authentication requirements:
4746             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4747             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4748             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4749             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4750                 authreq |= 1;
4751             }
4752             bool bonding = hci_stack->bondable;
4753             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4754                 // if we have received IO Cap Response, we're in responder role
4755                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4756                 if (bonding && !remote_bonding){
4757                     log_info("Remote not bonding, dropping local flag");
4758                     bonding = false;
4759                 }
4760             }
4761             if (bonding){
4762                 if (connection->bonding_flags & BONDING_DEDICATED){
4763                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4764                 } else {
4765                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4766                 }
4767             }
4768             uint8_t have_oob_data = 0;
4769 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4770             if (connection->classic_oob_c_192 != NULL){
4771                     have_oob_data |= 1;
4772             }
4773             if (connection->classic_oob_c_256 != NULL){
4774                 have_oob_data |= 2;
4775             }
4776 #endif
4777             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4778             return true;
4779         }
4780 
4781         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4782             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4783             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4784             return true;
4785         }
4786 
4787 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4788         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4789             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4790             const uint8_t zero[16] = { 0 };
4791             const uint8_t * r_192 = zero;
4792             const uint8_t * c_192 = zero;
4793             const uint8_t * r_256 = zero;
4794             const uint8_t * c_256 = zero;
4795             // verify P-256 OOB
4796             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4797                 c_256 = connection->classic_oob_c_256;
4798                 if (connection->classic_oob_r_256 != NULL) {
4799                     r_256 = connection->classic_oob_r_256;
4800                 }
4801             }
4802             // verify P-192 OOB
4803             if ((connection->classic_oob_c_192 != NULL)) {
4804                 c_192 = connection->classic_oob_c_192;
4805                 if (connection->classic_oob_r_192 != NULL) {
4806                     r_192 = connection->classic_oob_r_192;
4807                 }
4808             }
4809 
4810             // assess security
4811             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4812             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4813             if (need_level_4 && !can_reach_level_4){
4814                 log_info("Level 4 required, but not possible -> abort");
4815                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4816                 // send oob negative reply
4817                 c_256 = NULL;
4818                 c_192 = NULL;
4819             }
4820 
4821             // Reply
4822             if (c_256 != zero) {
4823                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4824             } else if (c_192 != zero){
4825                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4826             } else {
4827                 hci_stack->classic_oob_con_handle = connection->con_handle;
4828                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4829             }
4830             return true;
4831         }
4832 #endif
4833 
4834         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4835             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4836             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4837             return true;
4838         }
4839 
4840         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4841             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4842             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4843             return true;
4844         }
4845 
4846         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4847             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4848             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4849             return true;
4850         }
4851 
4852         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4853             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4854             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4855             connection->state = SENT_DISCONNECT;
4856             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4857             return true;
4858         }
4859 
4860         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4861             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4862             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4863             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4864             return true;
4865         }
4866 
4867         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4868             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4869             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4870             return true;
4871         }
4872         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4873             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4874             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4875             return true;
4876         }
4877 #endif
4878 
4879         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4880             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4881 #ifdef ENABLE_CLASSIC
4882             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4883 #endif
4884             if (connection->state != SENT_DISCONNECT){
4885                 connection->state = SENT_DISCONNECT;
4886                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4887                 return true;
4888             }
4889         }
4890 
4891 #ifdef ENABLE_CLASSIC
4892         uint16_t sniff_min_interval;
4893         switch (connection->sniff_min_interval){
4894             case 0:
4895                 break;
4896             case 0xffff:
4897                 connection->sniff_min_interval = 0;
4898                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4899                 return true;
4900             default:
4901                 sniff_min_interval = connection->sniff_min_interval;
4902                 connection->sniff_min_interval = 0;
4903                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4904                 return true;
4905         }
4906 
4907         if (connection->sniff_subrating_max_latency != 0xffff){
4908             uint16_t max_latency = connection->sniff_subrating_max_latency;
4909             connection->sniff_subrating_max_latency = 0;
4910             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4911             return true;
4912         }
4913 
4914         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4915             uint8_t service_type = (uint8_t) connection->qos_service_type;
4916             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4917             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);
4918             return true;
4919         }
4920 
4921         if (connection->request_role != HCI_ROLE_INVALID){
4922             hci_role_t role = connection->request_role;
4923             connection->request_role = HCI_ROLE_INVALID;
4924             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4925             return true;
4926         }
4927 #endif
4928 
4929 #ifdef ENABLE_BLE
4930         switch (connection->le_con_parameter_update_state){
4931             // response to L2CAP CON PARAMETER UPDATE REQUEST
4932             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4933                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4934                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4935                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4936                              0x0000, 0xffff);
4937                 return true;
4938             case CON_PARAMETER_UPDATE_REPLY:
4939                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4940                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4941                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4942                              0x0000, 0xffff);
4943                 return true;
4944             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4945                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4946                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4947                 return true;
4948             default:
4949                 break;
4950         }
4951         if (connection->le_phy_update_all_phys != 0xffu){
4952             uint8_t all_phys = connection->le_phy_update_all_phys;
4953             connection->le_phy_update_all_phys = 0xff;
4954             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);
4955             return true;
4956         }
4957 #endif
4958     }
4959     return false;
4960 }
4961 
4962 static void hci_run(void){
4963 
4964     bool done;
4965 
4966     // send continuation fragments first, as they block the prepared packet buffer
4967     done = hci_run_acl_fragments();
4968     if (done) return;
4969 
4970 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4971     // send host num completed packets next as they don't require num_cmd_packets > 0
4972     if (!hci_can_send_comand_packet_transport()) return;
4973     if (hci_stack->host_completed_packets){
4974         hci_host_num_completed_packets();
4975         return;
4976     }
4977 #endif
4978 
4979     if (!hci_can_send_command_packet_now()) return;
4980 
4981     // global/non-connection oriented commands
4982 
4983 
4984 #ifdef ENABLE_CLASSIC
4985     // general gap classic
4986     done = hci_run_general_gap_classic();
4987     if (done) return;
4988 #endif
4989 
4990 #ifdef ENABLE_BLE
4991     // general gap le
4992     done = hci_run_general_gap_le();
4993     if (done) return;
4994 #endif
4995 
4996     // send pending HCI commands
4997     done = hci_run_general_pending_commands();
4998     if (done) return;
4999 
5000     // stack state sub statemachines
5001     hci_connection_t * connection;
5002     switch (hci_stack->state){
5003         case HCI_STATE_INITIALIZING:
5004             hci_initializing_run();
5005             break;
5006 
5007         case HCI_STATE_HALTING:
5008 
5009             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5010             switch (hci_stack->substate){
5011                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5012                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5013 
5014 #ifdef ENABLE_BLE
5015 #ifdef ENABLE_LE_CENTRAL
5016                     // free whitelist entries
5017                     {
5018                         btstack_linked_list_iterator_t lit;
5019                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5020                         while (btstack_linked_list_iterator_has_next(&lit)){
5021                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5022                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5023                             btstack_memory_whitelist_entry_free(entry);
5024                         }
5025                     }
5026 #endif
5027 #endif
5028                     // close all open connections
5029                     connection =  (hci_connection_t *) hci_stack->connections;
5030                     if (connection){
5031                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5032                         if (!hci_can_send_command_packet_now()) return;
5033 
5034                         // check state
5035                         if (connection->state == SENT_DISCONNECT) return;
5036                         connection->state = SENT_DISCONNECT;
5037 
5038                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5039 
5040                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5041                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5042 
5043                         // ... which would be ignored anyway as we shutdown (free) the connection now
5044                         hci_shutdown_connection(connection);
5045 
5046                         // finally, send the disconnect command
5047                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5048                         return;
5049                     }
5050 
5051                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5052                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5053                         log_info("HCI_STATE_HALTING: wait 50 ms");
5054                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5055                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5056                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5057                         btstack_run_loop_add_timer(&hci_stack->timeout);
5058                         break;
5059                     }
5060 
5061                     /* fall through */
5062 
5063                 case HCI_HALTING_CLOSE:
5064                     log_info("HCI_STATE_HALTING, calling off");
5065 
5066                     // switch mode
5067                     hci_power_control_off();
5068 
5069                     log_info("HCI_STATE_HALTING, emitting state");
5070                     hci_emit_state();
5071                     log_info("HCI_STATE_HALTING, done");
5072                     break;
5073 
5074                 case HCI_HALTING_W4_TIMER:
5075                     // keep waiting
5076 
5077                     break;
5078                 default:
5079                     break;
5080             }
5081 
5082             break;
5083 
5084         case HCI_STATE_FALLING_ASLEEP:
5085             switch(hci_stack->substate) {
5086                 case HCI_FALLING_ASLEEP_DISCONNECT:
5087                     log_info("HCI_STATE_FALLING_ASLEEP");
5088                     // close all open connections
5089                     connection =  (hci_connection_t *) hci_stack->connections;
5090                     if (connection){
5091 
5092                         // send disconnect
5093                         if (!hci_can_send_command_packet_now()) return;
5094 
5095                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5096                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5097 
5098                         // send disconnected event right away - causes higher layer connections to get closed, too.
5099                         hci_shutdown_connection(connection);
5100                         return;
5101                     }
5102 
5103                     if (hci_classic_supported()){
5104                         // disable page and inquiry scan
5105                         if (!hci_can_send_command_packet_now()) return;
5106 
5107                         log_info("HCI_STATE_HALTING, disabling inq scans");
5108                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5109 
5110                         // continue in next sub state
5111                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5112                         break;
5113                     }
5114 
5115                     /* fall through */
5116 
5117                 case HCI_FALLING_ASLEEP_COMPLETE:
5118                     log_info("HCI_STATE_HALTING, calling sleep");
5119                     // switch mode
5120                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5121                     hci_emit_state();
5122                     break;
5123 
5124                 default:
5125                     break;
5126             }
5127             break;
5128 
5129         default:
5130             break;
5131     }
5132 }
5133 
5134 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5135     // house-keeping
5136 
5137 #ifdef ENABLE_CLASSIC
5138     bd_addr_t addr;
5139     hci_connection_t * conn;
5140 #endif
5141 #ifdef ENABLE_LE_CENTRAL
5142     uint8_t initiator_filter_policy;
5143 #endif
5144 
5145     uint16_t opcode = little_endian_read_16(packet, 0);
5146     switch (opcode) {
5147         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5148             hci_stack->loopback_mode = packet[3];
5149             break;
5150 
5151 #ifdef ENABLE_CLASSIC
5152         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5153             reverse_bd_addr(&packet[3], addr);
5154             log_info("Create_connection to %s", bd_addr_to_str(addr));
5155 
5156             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5157             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5158                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5159                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5160             }
5161 
5162             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5163             if (!conn) {
5164                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5165                 if (!conn) {
5166                     // notify client that alloc failed
5167                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5168                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5169                 }
5170                 conn->state = SEND_CREATE_CONNECTION;
5171                 conn->role  = HCI_ROLE_MASTER;
5172             }
5173 
5174             conn->con_handle = HCI_CON_HANDLE_INVALID;
5175             conn->role = HCI_ROLE_INVALID;
5176 
5177             log_info("conn state %u", conn->state);
5178             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5179             switch (conn->state) {
5180                 // if connection active exists
5181                 case OPEN:
5182                     // and OPEN, emit connection complete command
5183                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5184                     // packet not sent to controller
5185                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5186                 case RECEIVED_DISCONNECTION_COMPLETE:
5187                     // create connection triggered in disconnect complete event, let's do it now
5188                     break;
5189                 case SEND_CREATE_CONNECTION:
5190                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5191                     break;
5192                 default:
5193                     // otherwise, just ignore as it is already in the open process
5194                     // packet not sent to controller
5195                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5196             }
5197             conn->state = SENT_CREATE_CONNECTION;
5198 
5199             // track outgoing connection
5200             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5201             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5202             break;
5203         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5204             if (hci_stack->link_key_db) {
5205                 reverse_bd_addr(&packet[3], addr);
5206                 hci_stack->link_key_db->delete_link_key(addr);
5207             }
5208             break;
5209 
5210 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5211         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5212             // setup_synchronous_connection? Voice setting at offset 22
5213             // TODO: compare to current setting if sco connection already active
5214             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5215             break;
5216         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5217             // accept_synchronus_connection? Voice setting at offset 18
5218             // TODO: compare to current setting if sco connection already active
5219             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5220             break;
5221 #endif
5222 #endif
5223 
5224 #ifdef ENABLE_BLE
5225         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5226             hci_stack->le_random_address_set = 1;
5227             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5228             break;
5229 #ifdef ENABLE_LE_PERIPHERAL
5230         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5231             hci_stack->le_advertisements_active = packet[3] != 0;
5232             break;
5233 #endif
5234 #ifdef ENABLE_LE_CENTRAL
5235         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5236             // white list used?
5237             initiator_filter_policy = packet[7];
5238             switch (initiator_filter_policy) {
5239                 case 0:
5240                     // whitelist not used
5241                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5242                     break;
5243                 case 1:
5244                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5245                     break;
5246                 default:
5247                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5248                     break;
5249             }
5250             // track outgoing connection
5251             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5252             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5253             break;
5254         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5255             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5256             break;
5257 #endif
5258 #endif
5259         default:
5260             break;
5261     }
5262 
5263     hci_stack->num_cmd_packets--;
5264 
5265     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5266     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5267     if (err != 0){
5268         return ERROR_CODE_HARDWARE_FAILURE;
5269     }
5270     return ERROR_CODE_SUCCESS;
5271 }
5272 
5273 // disconnect because of security block
5274 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5275     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5276     if (!connection) return;
5277     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5278 }
5279 
5280 
5281 // Configure Secure Simple Pairing
5282 
5283 #ifdef ENABLE_CLASSIC
5284 
5285 // enable will enable SSP during init
5286 void gap_ssp_set_enable(int enable){
5287     hci_stack->ssp_enable = enable;
5288 }
5289 
5290 static int hci_local_ssp_activated(void){
5291     return gap_ssp_supported() && hci_stack->ssp_enable;
5292 }
5293 
5294 // if set, BTstack will respond to io capability request using authentication requirement
5295 void gap_ssp_set_io_capability(int io_capability){
5296     hci_stack->ssp_io_capability = io_capability;
5297 }
5298 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5299     hci_stack->ssp_authentication_requirement = authentication_requirement;
5300 }
5301 
5302 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5303 void gap_ssp_set_auto_accept(int auto_accept){
5304     hci_stack->ssp_auto_accept = auto_accept;
5305 }
5306 
5307 void gap_secure_connections_enable(bool enable){
5308     hci_stack->secure_connections_enable = enable;
5309 }
5310 
5311 #endif
5312 
5313 // va_list part of hci_send_cmd
5314 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5315     if (!hci_can_send_command_packet_now()){
5316         log_error("hci_send_cmd called but cannot send packet now");
5317         return ERROR_CODE_COMMAND_DISALLOWED;
5318     }
5319 
5320     // for HCI INITIALIZATION
5321     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5322     hci_stack->last_cmd_opcode = cmd->opcode;
5323 
5324     hci_reserve_packet_buffer();
5325     uint8_t * packet = hci_stack->hci_packet_buffer;
5326     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5327     uint8_t status = hci_send_cmd_packet(packet, size);
5328 
5329     // release packet buffer on error or for synchronous transport implementations
5330     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5331         hci_release_packet_buffer();
5332         hci_emit_transport_packet_sent();
5333     }
5334 
5335     return status;
5336 }
5337 
5338 /**
5339  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5340  */
5341 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5342     va_list argptr;
5343     va_start(argptr, cmd);
5344     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5345     va_end(argptr);
5346     return status;
5347 }
5348 
5349 // Create various non-HCI events.
5350 // TODO: generalize, use table similar to hci_create_command
5351 
5352 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5353     // dump packet
5354     if (dump) {
5355         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5356     }
5357 
5358     // dispatch to all event handlers
5359     btstack_linked_list_iterator_t it;
5360     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5361     while (btstack_linked_list_iterator_has_next(&it)){
5362         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5363         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5364     }
5365 }
5366 
5367 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5368     if (!hci_stack->acl_packet_handler) return;
5369     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5370 }
5371 
5372 #ifdef ENABLE_CLASSIC
5373 static void hci_notify_if_sco_can_send_now(void){
5374     // notify SCO sender if waiting
5375     if (!hci_stack->sco_waiting_for_can_send_now) return;
5376     if (hci_can_send_sco_packet_now()){
5377         hci_stack->sco_waiting_for_can_send_now = 0;
5378         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5379         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5380         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5381     }
5382 }
5383 
5384 // parsing end emitting has been merged to reduce code size
5385 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5386     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5387 
5388     uint8_t * eir_data;
5389     ad_context_t context;
5390     const uint8_t * name;
5391     uint8_t         name_len;
5392 
5393     if (size < 3) return;
5394 
5395     int event_type = hci_event_packet_get_type(packet);
5396     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5397     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5398 
5399     switch (event_type){
5400         case HCI_EVENT_INQUIRY_RESULT:
5401         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5402             if (size != (3 + (num_responses * 14))) return;
5403             break;
5404         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5405             if (size != 257) return;
5406             if (num_responses != 1) return;
5407             break;
5408         default:
5409             return;
5410     }
5411 
5412     // event[1] is set at the end
5413     int i;
5414     for (i=0; i<num_responses;i++){
5415         memset(event, 0, sizeof(event));
5416         event[0] = GAP_EVENT_INQUIRY_RESULT;
5417         uint8_t event_size = 27;    // if name is not set by EIR
5418 
5419         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5420         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5421         (void)memcpy(&event[9],
5422                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5423                      3); // class of device
5424         (void)memcpy(&event[12],
5425                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5426                      2); // clock offset
5427 
5428         switch (event_type){
5429             case HCI_EVENT_INQUIRY_RESULT:
5430                 // 14,15,16,17 = 0, size 18
5431                 break;
5432             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5433                 event[14] = 1;
5434                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5435                 // 16,17 = 0, size 18
5436                 break;
5437             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5438                 event[14] = 1;
5439                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5440                 // EIR packets only contain a single inquiry response
5441                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5442                 name = NULL;
5443                 // Iterate over EIR data
5444                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5445                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5446                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5447                     const uint8_t * data = ad_iterator_get_data(&context);
5448                     // Prefer Complete Local Name over Shortened Local Name
5449                     switch (data_type){
5450                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5451                             if (name) continue;
5452                             /* fall through */
5453                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5454                             name = data;
5455                             name_len = data_size;
5456                             break;
5457                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5458                             if (data_size != 8) break;
5459                             event[16] = 1;
5460                             memcpy(&event[17], data, 8);
5461                             break;
5462                         default:
5463                             break;
5464                     }
5465                 }
5466                 if (name){
5467                     event[25] = 1;
5468                     // truncate name if needed
5469                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5470                     event[26] = len;
5471                     (void)memcpy(&event[27], name, len);
5472                     event_size += len;
5473                 }
5474                 break;
5475             default:
5476                 return;
5477         }
5478         event[1] = event_size - 2;
5479         hci_emit_event(event, event_size, 1);
5480     }
5481 }
5482 #endif
5483 
5484 void hci_emit_state(void){
5485     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5486     uint8_t event[3];
5487     event[0] = BTSTACK_EVENT_STATE;
5488     event[1] = sizeof(event) - 2u;
5489     event[2] = hci_stack->state;
5490     hci_emit_event(event, sizeof(event), 1);
5491 }
5492 
5493 #ifdef ENABLE_CLASSIC
5494 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5495     uint8_t event[13];
5496     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5497     event[1] = sizeof(event) - 2;
5498     event[2] = status;
5499     little_endian_store_16(event, 3, con_handle);
5500     reverse_bd_addr(address, &event[5]);
5501     event[11] = 1; // ACL connection
5502     event[12] = 0; // encryption disabled
5503     hci_emit_event(event, sizeof(event), 1);
5504 }
5505 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5506     if (disable_l2cap_timeouts) return;
5507     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5508     uint8_t event[4];
5509     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5510     event[1] = sizeof(event) - 2;
5511     little_endian_store_16(event, 2, conn->con_handle);
5512     hci_emit_event(event, sizeof(event), 1);
5513 }
5514 #endif
5515 
5516 #ifdef ENABLE_BLE
5517 #ifdef ENABLE_LE_CENTRAL
5518 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){
5519     uint8_t event[21];
5520     event[0] = HCI_EVENT_LE_META;
5521     event[1] = sizeof(event) - 2u;
5522     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5523     event[3] = status;
5524     little_endian_store_16(event, 4, con_handle);
5525     event[6] = 0; // TODO: role
5526     event[7] = address_type;
5527     reverse_bd_addr(address, &event[8]);
5528     little_endian_store_16(event, 14, 0); // interval
5529     little_endian_store_16(event, 16, 0); // latency
5530     little_endian_store_16(event, 18, 0); // supervision timeout
5531     event[20] = 0; // master clock accuracy
5532     hci_emit_event(event, sizeof(event), 1);
5533 }
5534 #endif
5535 #endif
5536 
5537 static void hci_emit_transport_packet_sent(void){
5538     // notify upper stack that it might be possible to send again
5539     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5540     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5541 }
5542 
5543 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5544     uint8_t event[6];
5545     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5546     event[1] = sizeof(event) - 2u;
5547     event[2] = 0; // status = OK
5548     little_endian_store_16(event, 3, con_handle);
5549     event[5] = reason;
5550     hci_emit_event(event, sizeof(event), 1);
5551 }
5552 
5553 static void hci_emit_nr_connections_changed(void){
5554     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5555     uint8_t event[3];
5556     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5557     event[1] = sizeof(event) - 2u;
5558     event[2] = nr_hci_connections();
5559     hci_emit_event(event, sizeof(event), 1);
5560 }
5561 
5562 static void hci_emit_hci_open_failed(void){
5563     log_info("BTSTACK_EVENT_POWERON_FAILED");
5564     uint8_t event[2];
5565     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5566     event[1] = sizeof(event) - 2u;
5567     hci_emit_event(event, sizeof(event), 1);
5568 }
5569 
5570 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5571     log_info("hci_emit_dedicated_bonding_result %u ", status);
5572     uint8_t event[9];
5573     int pos = 0;
5574     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5575     event[pos++] = sizeof(event) - 2u;
5576     event[pos++] = status;
5577     reverse_bd_addr(address, &event[pos]);
5578     hci_emit_event(event, sizeof(event), 1);
5579 }
5580 
5581 
5582 #ifdef ENABLE_CLASSIC
5583 
5584 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5585     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5586     uint8_t event[5];
5587     int pos = 0;
5588     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5589     event[pos++] = sizeof(event) - 2;
5590     little_endian_store_16(event, 2, con_handle);
5591     pos += 2;
5592     event[pos++] = level;
5593     hci_emit_event(event, sizeof(event), 1);
5594 }
5595 
5596 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5597     if (!connection) return LEVEL_0;
5598     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5599     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5600     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5601     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5602     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5603     // LEVEL 4 always requires 128 bit encrytion key size
5604     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5605         security_level = LEVEL_3;
5606     }
5607     return security_level;
5608 }
5609 
5610 static void hci_emit_discoverable_enabled(uint8_t enabled){
5611     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5612     uint8_t event[3];
5613     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5614     event[1] = sizeof(event) - 2;
5615     event[2] = enabled;
5616     hci_emit_event(event, sizeof(event), 1);
5617 }
5618 
5619 // query if remote side supports eSCO
5620 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5621     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5622     if (!connection) return false;
5623     return (connection->remote_supported_features[0] & 1) != 0;
5624 }
5625 
5626 static bool hci_ssp_supported(hci_connection_t * connection){
5627     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5628     return (connection->bonding_flags & mask) == mask;
5629 }
5630 
5631 // query if remote side supports SSP
5632 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5633     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5634     if (!connection) return false;
5635     return hci_ssp_supported(connection) ? 1 : 0;
5636 }
5637 
5638 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5639     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5640 }
5641 
5642 // GAP API
5643 /**
5644  * @bbrief enable/disable bonding. default is enabled
5645  * @praram enabled
5646  */
5647 void gap_set_bondable_mode(int enable){
5648     hci_stack->bondable = enable ? 1 : 0;
5649 }
5650 /**
5651  * @brief Get bondable mode.
5652  * @return 1 if bondable
5653  */
5654 int gap_get_bondable_mode(void){
5655     return hci_stack->bondable;
5656 }
5657 
5658 /**
5659  * @brief map link keys to security levels
5660  */
5661 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5662     switch (link_key_type){
5663         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5664             return LEVEL_4;
5665         case COMBINATION_KEY:
5666         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5667             return LEVEL_3;
5668         default:
5669             return LEVEL_2;
5670     }
5671 }
5672 
5673 /**
5674  * @brief map link keys to secure connection yes/no
5675  */
5676 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5677     switch (link_key_type){
5678         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5679         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5680             return 1;
5681         default:
5682             return 0;
5683     }
5684 }
5685 
5686 /**
5687  * @brief map link keys to authenticated
5688  */
5689 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5690     switch (link_key_type){
5691         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5692         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5693             return 1;
5694         default:
5695             return 0;
5696     }
5697 }
5698 
5699 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5700     log_info("gap_mitm_protection_required_for_security_level %u", level);
5701     return level > LEVEL_2;
5702 }
5703 
5704 /**
5705  * @brief get current security level
5706  */
5707 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5708     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5709     if (!connection) return LEVEL_0;
5710     return gap_security_level_for_connection(connection);
5711 }
5712 
5713 /**
5714  * @brief request connection to device to
5715  * @result GAP_AUTHENTICATION_RESULT
5716  */
5717 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5718     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5719     if (!connection){
5720         hci_emit_security_level(con_handle, LEVEL_0);
5721         return;
5722     }
5723 
5724     btstack_assert(hci_is_le_connection(connection) == false);
5725 
5726     // 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)
5727     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5728     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5729         requested_level = LEVEL_4;
5730     }
5731 
5732     gap_security_level_t current_level = gap_security_level(con_handle);
5733     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5734         requested_level, connection->requested_security_level, current_level);
5735 
5736     // authentication active if authentication request was sent or planned level > 0
5737     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5738     if (authentication_active){
5739         // authentication already active
5740         if (connection->requested_security_level < requested_level){
5741             // increase requested level as new level is higher
5742             // TODO: handle re-authentication when done
5743             connection->requested_security_level = requested_level;
5744         }
5745     } else {
5746         // no request active, notify if security sufficient
5747         if (requested_level <= current_level){
5748             hci_emit_security_level(con_handle, current_level);
5749             return;
5750         }
5751 
5752         // store request
5753         connection->requested_security_level = requested_level;
5754 
5755         // start to authenticate connection
5756         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5757         hci_run();
5758     }
5759 }
5760 
5761 /**
5762  * @brief start dedicated bonding with device. disconnect after bonding
5763  * @param device
5764  * @param request MITM protection
5765  * @result GAP_DEDICATED_BONDING_COMPLETE
5766  */
5767 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5768 
5769     // create connection state machine
5770     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5771 
5772     if (!connection){
5773         return BTSTACK_MEMORY_ALLOC_FAILED;
5774     }
5775 
5776     // delete linkn key
5777     gap_drop_link_key_for_bd_addr(device);
5778 
5779     // configure LEVEL_2/3, dedicated bonding
5780     connection->state = SEND_CREATE_CONNECTION;
5781     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5782     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5783     connection->bonding_flags = BONDING_DEDICATED;
5784 
5785     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5786 
5787     // handle: connnection failure (connection complete != ok)
5788     // handle: authentication failure
5789     // handle: disconnect on done
5790 
5791     hci_run();
5792 
5793     return 0;
5794 }
5795 
5796 void gap_set_local_name(const char * local_name){
5797     hci_stack->local_name = local_name;
5798     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5799     // also update EIR if not set by user
5800     if (hci_stack->eir_data == NULL){
5801         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5802     }
5803     hci_run();
5804 }
5805 #endif
5806 
5807 
5808 #ifdef ENABLE_BLE
5809 
5810 #ifdef ENABLE_LE_CENTRAL
5811 void gap_start_scan(void){
5812     hci_stack->le_scanning_enabled = true;
5813     hci_run();
5814 }
5815 
5816 void gap_stop_scan(void){
5817     hci_stack->le_scanning_enabled = false;
5818     hci_run();
5819 }
5820 
5821 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5822     hci_stack->le_scan_type          = scan_type;
5823     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5824     hci_stack->le_scan_interval      = scan_interval;
5825     hci_stack->le_scan_window        = scan_window;
5826     hci_stack->le_scanning_param_update = true;
5827     hci_run();
5828 }
5829 
5830 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5831     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5832 }
5833 
5834 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5835     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5836     if (!conn){
5837         // disallow if le connection is already outgoing
5838         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5839             log_error("le connection already active");
5840             return ERROR_CODE_COMMAND_DISALLOWED;
5841         }
5842 
5843         log_info("gap_connect: no connection exists yet, creating context");
5844         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5845         if (!conn){
5846             // notify client that alloc failed
5847             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5848             log_info("gap_connect: failed to alloc hci_connection_t");
5849             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5850         }
5851 
5852         // set le connecting state
5853         if (hci_is_le_connection_type(addr_type)){
5854             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5855         }
5856 
5857         conn->state = SEND_CREATE_CONNECTION;
5858         log_info("gap_connect: send create connection next");
5859         hci_run();
5860         return ERROR_CODE_SUCCESS;
5861     }
5862 
5863     if (!hci_is_le_connection(conn) ||
5864         (conn->state == SEND_CREATE_CONNECTION) ||
5865         (conn->state == SENT_CREATE_CONNECTION)) {
5866         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5867         log_error("gap_connect: classic connection or connect is already being created");
5868         return GATT_CLIENT_IN_WRONG_STATE;
5869     }
5870 
5871     // check if connection was just disconnected
5872     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5873         log_info("gap_connect: send create connection (again)");
5874         conn->state = SEND_CREATE_CONNECTION;
5875         hci_run();
5876         return ERROR_CODE_SUCCESS;
5877     }
5878 
5879     log_info("gap_connect: context exists with state %u", conn->state);
5880     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5881     hci_run();
5882     return ERROR_CODE_SUCCESS;
5883 }
5884 
5885 // @assumption: only a single outgoing LE Connection exists
5886 static hci_connection_t * gap_get_outgoing_connection(void){
5887     btstack_linked_item_t *it;
5888     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5889         hci_connection_t * conn = (hci_connection_t *) it;
5890         if (!hci_is_le_connection(conn)) continue;
5891         switch (conn->state){
5892             case SEND_CREATE_CONNECTION:
5893             case SENT_CREATE_CONNECTION:
5894             case SENT_CANCEL_CONNECTION:
5895                 return conn;
5896             default:
5897                 break;
5898         };
5899     }
5900     return NULL;
5901 }
5902 
5903 uint8_t gap_connect_cancel(void){
5904     hci_connection_t * conn = gap_get_outgoing_connection();
5905     if (!conn) return 0;
5906     switch (conn->state){
5907         case SEND_CREATE_CONNECTION:
5908             // skip sending create connection and emit event instead
5909             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5910             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5911             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5912             btstack_memory_hci_connection_free( conn );
5913             break;
5914         case SENT_CREATE_CONNECTION:
5915             // request to send cancel connection
5916             conn->state = SEND_CANCEL_CONNECTION;
5917             hci_run();
5918             break;
5919         default:
5920             break;
5921     }
5922     return 0;
5923 }
5924 #endif
5925 
5926 #ifdef ENABLE_LE_CENTRAL
5927 /**
5928  * @brief Set connection parameters for outgoing connections
5929  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5930  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5931  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5932  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5933  * @param conn_latency, default: 4
5934  * @param supervision_timeout (unit: 10ms), default: 720 ms
5935  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5936  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5937  */
5938 
5939 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5940     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5941     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5942     hci_stack->le_connection_scan_interval = conn_scan_interval;
5943     hci_stack->le_connection_scan_window = conn_scan_window;
5944     hci_stack->le_connection_interval_min = conn_interval_min;
5945     hci_stack->le_connection_interval_max = conn_interval_max;
5946     hci_stack->le_connection_latency = conn_latency;
5947     hci_stack->le_supervision_timeout = supervision_timeout;
5948     hci_stack->le_minimum_ce_length = min_ce_length;
5949     hci_stack->le_maximum_ce_length = max_ce_length;
5950 }
5951 #endif
5952 
5953 /**
5954  * @brief Updates the connection parameters for a given LE connection
5955  * @param handle
5956  * @param conn_interval_min (unit: 1.25ms)
5957  * @param conn_interval_max (unit: 1.25ms)
5958  * @param conn_latency
5959  * @param supervision_timeout (unit: 10ms)
5960  * @returns 0 if ok
5961  */
5962 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5963     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5964     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5965     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5966     connection->le_conn_interval_min = conn_interval_min;
5967     connection->le_conn_interval_max = conn_interval_max;
5968     connection->le_conn_latency = conn_latency;
5969     connection->le_supervision_timeout = supervision_timeout;
5970     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5971     hci_run();
5972     return 0;
5973 }
5974 
5975 /**
5976  * @brief Request an update of the connection parameter for a given LE connection
5977  * @param handle
5978  * @param conn_interval_min (unit: 1.25ms)
5979  * @param conn_interval_max (unit: 1.25ms)
5980  * @param conn_latency
5981  * @param supervision_timeout (unit: 10ms)
5982  * @returns 0 if ok
5983  */
5984 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5985     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5986     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5987     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5988     connection->le_conn_interval_min = conn_interval_min;
5989     connection->le_conn_interval_max = conn_interval_max;
5990     connection->le_conn_latency = conn_latency;
5991     connection->le_supervision_timeout = supervision_timeout;
5992     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5993     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5994     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5995     return 0;
5996 }
5997 
5998 #ifdef ENABLE_LE_PERIPHERAL
5999 
6000 /**
6001  * @brief Set Advertisement Data
6002  * @param advertising_data_length
6003  * @param advertising_data (max 31 octets)
6004  * @note data is not copied, pointer has to stay valid
6005  */
6006 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6007     hci_stack->le_advertisements_data_len = advertising_data_length;
6008     hci_stack->le_advertisements_data = advertising_data;
6009     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6010     hci_run();
6011 }
6012 
6013 /**
6014  * @brief Set Scan Response Data
6015  * @param advertising_data_length
6016  * @param advertising_data (max 31 octets)
6017  * @note data is not copied, pointer has to stay valid
6018  */
6019 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6020     hci_stack->le_scan_response_data_len = scan_response_data_length;
6021     hci_stack->le_scan_response_data = scan_response_data;
6022     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6023     hci_run();
6024 }
6025 
6026 /**
6027  * @brief Set Advertisement Parameters
6028  * @param adv_int_min
6029  * @param adv_int_max
6030  * @param adv_type
6031  * @param direct_address_type
6032  * @param direct_address
6033  * @param channel_map
6034  * @param filter_policy
6035  *
6036  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6037  */
6038  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6039     uint8_t direct_address_typ, bd_addr_t direct_address,
6040     uint8_t channel_map, uint8_t filter_policy) {
6041 
6042     hci_stack->le_advertisements_interval_min = adv_int_min;
6043     hci_stack->le_advertisements_interval_max = adv_int_max;
6044     hci_stack->le_advertisements_type = adv_type;
6045     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6046     hci_stack->le_advertisements_channel_map = channel_map;
6047     hci_stack->le_advertisements_filter_policy = filter_policy;
6048     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6049                  6);
6050 
6051     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6052     hci_run();
6053  }
6054 
6055 /**
6056  * @brief Enable/Disable Advertisements
6057  * @param enabled
6058  */
6059 void gap_advertisements_enable(int enabled){
6060     hci_stack->le_advertisements_enabled = enabled != 0;
6061     hci_update_advertisements_enabled_for_current_roles();
6062     hci_run();
6063 }
6064 
6065 #endif
6066 
6067 void hci_le_set_own_address_type(uint8_t own_address_type){
6068     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6069     if (own_address_type == hci_stack->le_own_addr_type) return;
6070     hci_stack->le_own_addr_type = own_address_type;
6071 
6072 #ifdef ENABLE_LE_PERIPHERAL
6073     // update advertisement parameters, too
6074     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6075     hci_run();
6076 #endif
6077 #ifdef ENABLE_LE_CENTRAL
6078     // note: we don't update scan parameters or modify ongoing connection attempts
6079 #endif
6080 }
6081 
6082 #endif
6083 
6084 uint8_t gap_disconnect(hci_con_handle_t handle){
6085     hci_connection_t * conn = hci_connection_for_handle(handle);
6086     if (!conn){
6087         hci_emit_disconnection_complete(handle, 0);
6088         return 0;
6089     }
6090     // ignore if already disconnected
6091     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6092         return 0;
6093     }
6094     conn->state = SEND_DISCONNECT;
6095     hci_run();
6096     return 0;
6097 }
6098 
6099 int gap_read_rssi(hci_con_handle_t con_handle){
6100     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6101     if (hci_connection == NULL) return 0;
6102     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6103     hci_run();
6104     return 1;
6105 }
6106 
6107 /**
6108  * @brief Get connection type
6109  * @param con_handle
6110  * @result connection_type
6111  */
6112 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6113     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6114     if (!conn) return GAP_CONNECTION_INVALID;
6115     switch (conn->address_type){
6116         case BD_ADDR_TYPE_LE_PUBLIC:
6117         case BD_ADDR_TYPE_LE_RANDOM:
6118             return GAP_CONNECTION_LE;
6119         case BD_ADDR_TYPE_SCO:
6120             return GAP_CONNECTION_SCO;
6121         case BD_ADDR_TYPE_ACL:
6122             return GAP_CONNECTION_ACL;
6123         default:
6124             return GAP_CONNECTION_INVALID;
6125     }
6126 }
6127 
6128 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6129     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6130     if (!conn) return HCI_ROLE_INVALID;
6131     return (hci_role_t) conn->role;
6132 }
6133 
6134 
6135 #ifdef ENABLE_CLASSIC
6136 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6137     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6138     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6139     conn->request_role = role;
6140     hci_run();
6141     return ERROR_CODE_SUCCESS;
6142 }
6143 #endif
6144 
6145 #ifdef ENABLE_BLE
6146 
6147 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){
6148     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6149     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6150 
6151     conn->le_phy_update_all_phys    = all_phys;
6152     conn->le_phy_update_tx_phys     = tx_phys;
6153     conn->le_phy_update_rx_phys     = rx_phys;
6154     conn->le_phy_update_phy_options = phy_options;
6155 
6156     hci_run();
6157 
6158     return 0;
6159 }
6160 
6161 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6162     // check if already in list
6163     btstack_linked_list_iterator_t it;
6164     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6165     while (btstack_linked_list_iterator_has_next(&it)) {
6166         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6167         if (entry->address_type != address_type) {
6168             continue;
6169         }
6170         if (memcmp(entry->address, address, 6) != 0) {
6171             continue;
6172         }
6173 		// disallow if already scheduled to add
6174 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6175 			return ERROR_CODE_COMMAND_DISALLOWED;
6176 		}
6177 		// still on controller, but scheduled to remove -> re-add
6178 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6179 		return ERROR_CODE_SUCCESS;
6180     }
6181     // alloc and add to list
6182     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6183     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6184     entry->address_type = address_type;
6185     (void)memcpy(entry->address, address, 6);
6186     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6187     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6188     return ERROR_CODE_SUCCESS;
6189 }
6190 
6191 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6192     btstack_linked_list_iterator_t it;
6193     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6194     while (btstack_linked_list_iterator_has_next(&it)){
6195         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6196         if (entry->address_type != address_type) {
6197             continue;
6198         }
6199         if (memcmp(entry->address, address, 6) != 0) {
6200             continue;
6201         }
6202         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6203             // remove from controller if already present
6204             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6205         }  else {
6206             // directly remove entry from whitelist
6207             btstack_linked_list_iterator_remove(&it);
6208             btstack_memory_whitelist_entry_free(entry);
6209         }
6210         return ERROR_CODE_SUCCESS;
6211     }
6212     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6213 }
6214 
6215 static void hci_whitelist_clear(void){
6216     btstack_linked_list_iterator_t it;
6217     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6218     while (btstack_linked_list_iterator_has_next(&it)){
6219         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6220         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6221             // remove from controller if already present
6222             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6223             continue;
6224         }
6225         // directly remove entry from whitelist
6226         btstack_linked_list_iterator_remove(&it);
6227         btstack_memory_whitelist_entry_free(entry);
6228     }
6229 }
6230 
6231 /**
6232  * @brief Clear Whitelist
6233  * @returns 0 if ok
6234  */
6235 uint8_t gap_whitelist_clear(void){
6236     hci_whitelist_clear();
6237     hci_run();
6238     return ERROR_CODE_SUCCESS;
6239 }
6240 
6241 /**
6242  * @brief Add Device to Whitelist
6243  * @param address_typ
6244  * @param address
6245  * @returns 0 if ok
6246  */
6247 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6248     uint8_t status = hci_whitelist_add(address_type, address);
6249     if (status){
6250         return status;
6251     }
6252     hci_run();
6253     return ERROR_CODE_SUCCESS;
6254 }
6255 
6256 /**
6257  * @brief Remove Device from Whitelist
6258  * @param address_typ
6259  * @param address
6260  * @returns 0 if ok
6261  */
6262 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6263     uint8_t status = hci_whitelist_remove(address_type, address);
6264     if (status){
6265         return status;
6266     }
6267     hci_run();
6268     return ERROR_CODE_SUCCESS;
6269 }
6270 
6271 #ifdef ENABLE_LE_CENTRAL
6272 /**
6273  *  @brief Connect with Whitelist
6274  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6275  *  @returns - if ok
6276  */
6277 uint8_t gap_connect_with_whitelist(void){
6278     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6279         return ERROR_CODE_COMMAND_DISALLOWED;
6280     }
6281     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6282     hci_run();
6283     return ERROR_CODE_SUCCESS;
6284 }
6285 
6286 /**
6287  * @brief Auto Connection Establishment - Start Connecting to device
6288  * @param address_typ
6289  * @param address
6290  * @returns 0 if ok
6291  */
6292 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6293     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6294         return ERROR_CODE_COMMAND_DISALLOWED;
6295     }
6296 
6297     uint8_t status = hci_whitelist_add(address_type, address);
6298     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6299         return status;
6300     }
6301 
6302     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6303 
6304     hci_run();
6305     return ERROR_CODE_SUCCESS;
6306 }
6307 
6308 /**
6309  * @brief Auto Connection Establishment - Stop Connecting to device
6310  * @param address_typ
6311  * @param address
6312  * @returns 0 if ok
6313  */
6314 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6315     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6316         return ERROR_CODE_COMMAND_DISALLOWED;
6317     }
6318 
6319     hci_whitelist_remove(address_type, address);
6320     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6321         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6322     }
6323     hci_run();
6324     return 0;
6325 }
6326 
6327 /**
6328  * @brief Auto Connection Establishment - Stop everything
6329  * @note  Convenience function to stop all active auto connection attempts
6330  */
6331 uint8_t gap_auto_connection_stop_all(void){
6332     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6333         return ERROR_CODE_COMMAND_DISALLOWED;
6334     }
6335     hci_whitelist_clear();
6336     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6337     hci_run();
6338     return ERROR_CODE_SUCCESS;
6339 }
6340 
6341 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6342     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6343     if (!conn) return 0;
6344     return conn->le_connection_interval;
6345 }
6346 #endif
6347 #endif
6348 
6349 #ifdef ENABLE_CLASSIC
6350 /**
6351  * @brief Set Extended Inquiry Response data
6352  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6353  * @note has to be done before stack starts up
6354  */
6355 void gap_set_extended_inquiry_response(const uint8_t * data){
6356     hci_stack->eir_data = data;
6357     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6358     hci_run();
6359 }
6360 
6361 /**
6362  * @brief Start GAP Classic Inquiry
6363  * @param duration in 1.28s units
6364  * @return 0 if ok
6365  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6366  */
6367 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6368     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6369     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6370     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6371         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6372     }
6373     hci_stack->inquiry_state = duration_in_1280ms_units;
6374     hci_run();
6375     return 0;
6376 }
6377 
6378 /**
6379  * @brief Stop GAP Classic Inquiry
6380  * @returns 0 if ok
6381  */
6382 int gap_inquiry_stop(void){
6383     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6384         // emit inquiry complete event, before it even started
6385         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6386         hci_emit_event(event, sizeof(event), 1);
6387         return 0;
6388     }
6389     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6390     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6391     hci_run();
6392     return 0;
6393 }
6394 
6395 void gap_inquiry_set_lap(uint32_t lap){
6396     hci_stack->inquiry_lap = lap;
6397 }
6398 
6399 
6400 /**
6401  * @brief Remote Name Request
6402  * @param addr
6403  * @param page_scan_repetition_mode
6404  * @param clock_offset only used when bit 15 is set
6405  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6406  */
6407 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6408     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6409     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6410     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6411     hci_stack->remote_name_clock_offset = clock_offset;
6412     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6413     hci_run();
6414     return 0;
6415 }
6416 
6417 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6418     hci_stack->gap_pairing_state = state;
6419     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6420     hci_run();
6421     return 0;
6422 }
6423 
6424 /**
6425  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6426  * @param addr
6427  * @param pin_data
6428  * @param pin_len
6429  * @return 0 if ok
6430  */
6431 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6432     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6433     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6434     hci_stack->gap_pairing_pin_len = pin_len;
6435     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6436 }
6437 
6438 /**
6439  * @brief Legacy Pairing Pin Code Response
6440  * @param addr
6441  * @param pin
6442  * @return 0 if ok
6443  */
6444 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6445     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6446 }
6447 
6448 /**
6449  * @brief Abort Legacy Pairing
6450  * @param addr
6451  * @param pin
6452  * @return 0 if ok
6453  */
6454 int gap_pin_code_negative(bd_addr_t addr){
6455     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6456     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6457 }
6458 
6459 /**
6460  * @brief SSP Passkey Response
6461  * @param addr
6462  * @param passkey
6463  * @return 0 if ok
6464  */
6465 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6466     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6467     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6468     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6469 }
6470 
6471 /**
6472  * @brief Abort SSP Passkey Entry/Pairing
6473  * @param addr
6474  * @param pin
6475  * @return 0 if ok
6476  */
6477 int gap_ssp_passkey_negative(const bd_addr_t addr){
6478     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6479     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6480 }
6481 
6482 /**
6483  * @brief Accept SSP Numeric Comparison
6484  * @param addr
6485  * @param passkey
6486  * @return 0 if ok
6487  */
6488 int gap_ssp_confirmation_response(const bd_addr_t addr){
6489     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6490     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6491 }
6492 
6493 /**
6494  * @brief Abort SSP Numeric Comparison/Pairing
6495  * @param addr
6496  * @param pin
6497  * @return 0 if ok
6498  */
6499 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6500     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6501     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6502 }
6503 
6504 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6505 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6506     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6507     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6508     connectionSetAuthenticationFlags(conn, flag);
6509     hci_run();
6510     return ERROR_CODE_SUCCESS;
6511 }
6512 #endif
6513 
6514 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6515 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6516     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6517 }
6518 
6519 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6520     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6521 }
6522 #endif
6523 
6524 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6525 /**
6526  * @brief Report Remote OOB Data
6527  * @param bd_addr
6528  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6529  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6530  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6531  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6532  */
6533 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){
6534     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6535     if (connection == NULL) {
6536         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6537     }
6538     connection->classic_oob_c_192 = c_192;
6539     connection->classic_oob_r_192 = r_192;
6540 
6541     // ignore P-256 if not supported by us
6542     if (hci_stack->secure_connections_active){
6543         connection->classic_oob_c_256 = c_256;
6544         connection->classic_oob_r_256 = r_256;
6545     }
6546 
6547     return ERROR_CODE_SUCCESS;
6548 }
6549 /**
6550  * @brief Generate new OOB data
6551  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6552  */
6553 void gap_ssp_generate_oob_data(void){
6554     hci_stack->classic_read_local_oob_data = true;
6555     hci_run();
6556 }
6557 
6558 #endif
6559 
6560 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6561 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6562     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6563     if (connection == NULL) {
6564         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6565     }
6566 
6567     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6568     connection->link_key_type = type;
6569 
6570     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6571 }
6572 
6573 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6574 /**
6575  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6576  * @param inquiry_mode see bluetooth_defines.h
6577  */
6578 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6579     hci_stack->inquiry_mode = inquiry_mode;
6580 }
6581 
6582 /**
6583  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6584  */
6585 void hci_set_sco_voice_setting(uint16_t voice_setting){
6586     hci_stack->sco_voice_setting = voice_setting;
6587 }
6588 
6589 /**
6590  * @brief Get SCO Voice Setting
6591  * @return current voice setting
6592  */
6593 uint16_t hci_get_sco_voice_setting(void){
6594     return hci_stack->sco_voice_setting;
6595 }
6596 
6597 static int hci_have_usb_transport(void){
6598     if (!hci_stack->hci_transport) return 0;
6599     const char * transport_name = hci_stack->hci_transport->name;
6600     if (!transport_name) return 0;
6601     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6602 }
6603 
6604 /** @brief Get SCO packet length for current SCO Voice setting
6605  *  @note  Using SCO packets of the exact length is required for USB transfer
6606  *  @return Length of SCO packets in bytes (not audio frames)
6607  */
6608 uint16_t hci_get_sco_packet_length(void){
6609     uint16_t sco_packet_length = 0;
6610 
6611 #ifdef ENABLE_SCO_OVER_HCI
6612     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6613     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6614 
6615     if (hci_have_usb_transport()){
6616         // see Core Spec for H2 USB Transfer.
6617         // 3 byte SCO header + 24 bytes per connection
6618         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6619         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6620     } else {
6621         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6622         sco_packet_length = 3 + 60 * multiplier;
6623         // assert that it still fits inside an SCO buffer
6624         if (sco_packet_length > hci_stack->sco_data_packet_length){
6625             sco_packet_length = 3 + 60;
6626         }
6627     }
6628 #endif
6629 
6630 #ifdef HAVE_SCO_TRANSPORT
6631     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6632     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6633     sco_packet_length = 3 + 60 * multiplier;
6634 #endif
6635     return sco_packet_length;
6636 }
6637 
6638 /**
6639 * @brief Sets the master/slave policy
6640 * @param policy (0: attempt to become master, 1: let connecting device decide)
6641 */
6642 void hci_set_master_slave_policy(uint8_t policy){
6643     hci_stack->master_slave_policy = policy;
6644 }
6645 
6646 #endif
6647 
6648 HCI_STATE hci_get_state(void){
6649     return hci_stack->state;
6650 }
6651 
6652 #ifdef ENABLE_CLASSIC
6653 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6654     hci_stack->gap_classic_accept_callback = accept_callback;
6655 }
6656 #endif
6657 
6658 /**
6659  * @brief Set callback for Bluetooth Hardware Error
6660  */
6661 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6662     hci_stack->hardware_error_callback = fn;
6663 }
6664 
6665 void hci_disconnect_all(void){
6666     btstack_linked_list_iterator_t it;
6667     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6668     while (btstack_linked_list_iterator_has_next(&it)){
6669         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6670         if (con->state == SENT_DISCONNECT) continue;
6671         con->state = SEND_DISCONNECT;
6672     }
6673     hci_run();
6674 }
6675 
6676 uint16_t hci_get_manufacturer(void){
6677     return hci_stack->manufacturer;
6678 }
6679 
6680 #ifdef ENABLE_BLE
6681 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6682     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6683     if (!hci_con) return NULL;
6684     return &hci_con->sm_connection;
6685 }
6686 
6687 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6688 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6689 #endif
6690 
6691 int gap_encryption_key_size(hci_con_handle_t con_handle){
6692     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6693     if (hci_connection == NULL) return 0;
6694     if (hci_is_le_connection(hci_connection)){
6695 #ifdef ENABLE_BLE
6696         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6697         if (sm_conn->sm_connection_encrypted) {
6698             return sm_conn->sm_actual_encryption_key_size;
6699         }
6700 #endif
6701     } else {
6702 #ifdef ENABLE_CLASSIC
6703         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6704             return hci_connection->encryption_key_size;
6705         }
6706 #endif
6707     }
6708     return 0;
6709 }
6710 
6711 int gap_authenticated(hci_con_handle_t con_handle){
6712     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6713     if (hci_connection == NULL) return 0;
6714 
6715     switch (hci_connection->address_type){
6716 #ifdef ENABLE_BLE
6717         case BD_ADDR_TYPE_LE_PUBLIC:
6718         case BD_ADDR_TYPE_LE_RANDOM:
6719             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6720             return hci_connection->sm_connection.sm_connection_authenticated;
6721 #endif
6722 #ifdef ENABLE_CLASSIC
6723         case BD_ADDR_TYPE_SCO:
6724         case BD_ADDR_TYPE_ACL:
6725             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6726 #endif
6727         default:
6728             return 0;
6729     }
6730 }
6731 
6732 int gap_secure_connection(hci_con_handle_t con_handle){
6733     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6734     if (hci_connection == NULL) return 0;
6735 
6736     switch (hci_connection->address_type){
6737 #ifdef ENABLE_BLE
6738         case BD_ADDR_TYPE_LE_PUBLIC:
6739         case BD_ADDR_TYPE_LE_RANDOM:
6740             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6741             return hci_connection->sm_connection.sm_connection_sc;
6742 #endif
6743 #ifdef ENABLE_CLASSIC
6744         case BD_ADDR_TYPE_SCO:
6745         case BD_ADDR_TYPE_ACL:
6746             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6747 #endif
6748         default:
6749             return 0;
6750     }
6751 }
6752 
6753 bool gap_bonded(hci_con_handle_t con_handle){
6754 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6755 	if (hci_connection == NULL) return 0;
6756 
6757 #ifdef ENABLE_CLASSIC
6758 	link_key_t link_key;
6759 	link_key_type_t link_key_type;
6760 #endif
6761 	switch (hci_connection->address_type){
6762 #ifdef ENABLE_BLE
6763 		case BD_ADDR_TYPE_LE_PUBLIC:
6764 		case BD_ADDR_TYPE_LE_RANDOM:
6765 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6766 #endif
6767 #ifdef ENABLE_CLASSIC
6768 		case BD_ADDR_TYPE_SCO:
6769 		case BD_ADDR_TYPE_ACL:
6770 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6771 #endif
6772 		default:
6773 			return false;
6774 	}
6775 }
6776 
6777 #ifdef ENABLE_BLE
6778 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6779     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6780     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6781     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6782     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6783     return sm_conn->sm_connection_authorization_state;
6784 }
6785 #endif
6786 
6787 #ifdef ENABLE_CLASSIC
6788 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){
6789     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6790     if (!conn) return GAP_CONNECTION_INVALID;
6791     conn->sniff_min_interval = sniff_min_interval;
6792     conn->sniff_max_interval = sniff_max_interval;
6793     conn->sniff_attempt = sniff_attempt;
6794     conn->sniff_timeout = sniff_timeout;
6795     hci_run();
6796     return 0;
6797 }
6798 
6799 /**
6800  * @brief Exit Sniff mode
6801  * @param con_handle
6802  @ @return 0 if ok
6803  */
6804 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6805     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6806     if (!conn) return GAP_CONNECTION_INVALID;
6807     conn->sniff_min_interval = 0xffff;
6808     hci_run();
6809     return 0;
6810 }
6811 
6812 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){
6813     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6814     if (!conn) return GAP_CONNECTION_INVALID;
6815     conn->sniff_subrating_max_latency = max_latency;
6816     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6817     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6818     hci_run();
6819     return ERROR_CODE_SUCCESS;
6820 }
6821 
6822 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){
6823     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6824     if (!conn) return GAP_CONNECTION_INVALID;
6825     conn->qos_service_type = service_type;
6826     conn->qos_token_rate = token_rate;
6827     conn->qos_peak_bandwidth = peak_bandwidth;
6828     conn->qos_latency = latency;
6829     conn->qos_delay_variation = delay_variation;
6830     hci_run();
6831     return ERROR_CODE_SUCCESS;
6832 }
6833 
6834 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6835     hci_stack->new_page_scan_interval = page_scan_interval;
6836     hci_stack->new_page_scan_window = page_scan_window;
6837     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6838     hci_run();
6839 }
6840 
6841 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6842     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6843     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6844     hci_run();
6845 }
6846 
6847 #endif
6848 
6849 void hci_halting_defer(void){
6850     if (hci_stack->state != HCI_STATE_HALTING) return;
6851     switch (hci_stack->substate){
6852         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6853         case HCI_HALTING_CLOSE:
6854             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6855             break;
6856         default:
6857             break;
6858     }
6859 }
6860 
6861 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6862 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6863     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6864     if (le_device_db_index >= le_device_db_max_count()) return;
6865     uint8_t offset = le_device_db_index >> 3;
6866     uint8_t mask = 1 << (le_device_db_index & 7);
6867     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6868     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6869     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6870         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6871     }
6872 }
6873 
6874 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6875 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6876 	if (le_device_db_index >= le_device_db_max_count()) return;
6877 	uint8_t offset = le_device_db_index >> 3;
6878 	uint8_t mask = 1 << (le_device_db_index & 7);
6879 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6880 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6881 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6882 	}
6883 }
6884 
6885 uint8_t gap_load_resolving_list_from_le_device_db(void){
6886 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6887 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6888 	}
6889 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6890 		// restart le resolving list update
6891 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6892 	}
6893 	return ERROR_CODE_SUCCESS;
6894 }
6895 #endif
6896 
6897 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6898 void hci_setup_test_connections_fuzz(void){
6899     hci_connection_t * conn;
6900 
6901     // default address: 66:55:44:33:00:01
6902     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6903 
6904     // setup Controller info
6905     hci_stack->num_cmd_packets = 255;
6906     hci_stack->acl_packets_total_num = 255;
6907 
6908     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6909     addr[5] = 0x01;
6910     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
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 incoming Classic SCO connection with con handle 0x0002
6917     addr[5] = 0x02;
6918     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6919     conn->con_handle = addr[5];
6920     conn->role  = HCI_ROLE_SLAVE;
6921     conn->state = RECEIVED_CONNECTION_REQUEST;
6922     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6923 
6924     // setup ready Classic ACL connection with con handle 0x0003
6925     addr[5] = 0x03;
6926     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
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 Classic SCO connection with con handle 0x0004
6933     addr[5] = 0x04;
6934     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
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 
6940     // setup ready LE ACL connection with con handle 0x005 and public address
6941     addr[5] = 0x05;
6942     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6943     conn->con_handle = addr[5];
6944     conn->role  = HCI_ROLE_SLAVE;
6945     conn->state = OPEN;
6946     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6947     conn->sm_connection.sm_connection_encrypted = 1;
6948 }
6949 
6950 void hci_free_connections_fuzz(void){
6951     btstack_linked_list_iterator_t it;
6952     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6953     while (btstack_linked_list_iterator_has_next(&it)){
6954         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6955         btstack_linked_list_iterator_remove(&it);
6956         btstack_memory_hci_connection_free(con);
6957     }
6958 }
6959 void hci_simulate_working_fuzz(void){
6960     hci_init_done();
6961     hci_stack->num_cmd_packets = 255;
6962 }
6963 #endif
6964