xref: /btstack/src/hci.c (revision 2ac1dc76c9f11326904f6859da1d08322744e245)
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[11];
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     // write page timeout
1351     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_TIMEOUT) != 0) {
1352         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_TIMEOUT;
1353         hci_send_cmd(&hci_write_page_timeout, hci_stack->page_timeout);
1354         return;
1355     }
1356     // send scan enable
1357     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1358         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1359         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1360         return;
1361     }
1362 }
1363 #endif
1364 
1365 #ifndef HAVE_HOST_CONTROLLER_API
1366 
1367 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1368     if (!hci_stack->config) return 0;
1369     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1370     // Limit baud rate for Broadcom chipsets to 3 mbps
1371     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1372         baud_rate = 3000000;
1373     }
1374     return baud_rate;
1375 }
1376 
1377 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1378     UNUSED(ds);
1379 
1380     switch (hci_stack->substate){
1381         case HCI_INIT_W4_SEND_RESET:
1382             log_info("Resend HCI Reset");
1383             hci_stack->substate = HCI_INIT_SEND_RESET;
1384             hci_stack->num_cmd_packets = 1;
1385             hci_run();
1386             break;
1387         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1388             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1389             if (hci_stack->hci_transport->reset_link){
1390                 hci_stack->hci_transport->reset_link();
1391             }
1392 
1393             /* fall through */
1394 
1395         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1396             log_info("Resend HCI Reset - CSR Warm Boot");
1397             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1398             hci_stack->num_cmd_packets = 1;
1399             hci_run();
1400             break;
1401         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1402             if (hci_stack->hci_transport->set_baudrate){
1403                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1404                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1405                 hci_stack->hci_transport->set_baudrate(baud_rate);
1406             }
1407             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1408             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1409                 if (hci_stack->hci_transport->reset_link){
1410                     log_info("Link Reset");
1411                     hci_stack->hci_transport->reset_link();
1412                 }
1413                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1414                 hci_run();
1415             }
1416             break;
1417         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1418             // otherwise continue
1419             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1420             hci_send_cmd(&hci_read_local_supported_commands);
1421             break;
1422         default:
1423             break;
1424     }
1425 }
1426 #endif
1427 
1428 static void hci_initializing_next_state(void){
1429     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1430 }
1431 
1432 static void hci_init_done(void){
1433     // done. tell the app
1434     log_info("hci_init_done -> HCI_STATE_WORKING");
1435     hci_stack->state = HCI_STATE_WORKING;
1436     hci_emit_state();
1437 }
1438 
1439 // assumption: hci_can_send_command_packet_now() == true
1440 static void hci_initializing_run(void){
1441     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1442 
1443 #ifndef HAVE_HOST_CONTROLLER_API
1444     bool need_baud_change = hci_stack->config
1445             && hci_stack->chipset
1446             && hci_stack->chipset->set_baudrate_command
1447             && hci_stack->hci_transport->set_baudrate
1448             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1449 #endif
1450 
1451     switch (hci_stack->substate){
1452         case HCI_INIT_SEND_RESET:
1453             hci_state_reset();
1454 
1455 #ifndef HAVE_HOST_CONTROLLER_API
1456             // prepare reset if command complete not received in 100ms
1457             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1458             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1459             btstack_run_loop_add_timer(&hci_stack->timeout);
1460 #endif
1461             // send command
1462             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1463             hci_send_cmd(&hci_reset);
1464             break;
1465         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1466             hci_send_cmd(&hci_read_local_version_information);
1467             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1468             break;
1469 
1470 #ifndef HAVE_HOST_CONTROLLER_API
1471         case HCI_INIT_SEND_READ_LOCAL_NAME:
1472             hci_send_cmd(&hci_read_local_name);
1473             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1474             break;
1475         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1476             hci_state_reset();
1477             // prepare reset if command complete not received in 100ms
1478             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1479             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1480             btstack_run_loop_add_timer(&hci_stack->timeout);
1481             // send command
1482             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1483             hci_send_cmd(&hci_reset);
1484             break;
1485         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1486             hci_state_reset();
1487             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1488             hci_send_cmd(&hci_reset);
1489             break;
1490         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1491             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1492             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1493             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1494             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1495             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1496             break;
1497         }
1498         case HCI_INIT_SET_BD_ADDR:
1499             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1500             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1501             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1502             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1503             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1504             break;
1505         case HCI_INIT_SEND_BAUD_CHANGE:
1506             if (need_baud_change) {
1507                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1508                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1509                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1510                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1511                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1512                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1513                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1514                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1515                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1516                     btstack_run_loop_add_timer(&hci_stack->timeout);
1517                }
1518                break;
1519             }
1520 
1521             /* fall through */
1522 
1523         case HCI_INIT_CUSTOM_INIT:
1524             // Custom initialization
1525             if (hci_stack->chipset && hci_stack->chipset->next_command){
1526                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1527                 bool send_cmd = false;
1528                 switch (hci_stack->chipset_result){
1529                     case BTSTACK_CHIPSET_VALID_COMMAND:
1530                         send_cmd = true;
1531                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1532                         break;
1533                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1534                         send_cmd = true;
1535                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1536                         log_info("CSR Warm Boot");
1537                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1538                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1539                         btstack_run_loop_add_timer(&hci_stack->timeout);
1540                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1541                             && hci_stack->config
1542                             && hci_stack->chipset
1543                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1544                             && hci_stack->hci_transport->set_baudrate
1545                             && hci_transport_uart_get_main_baud_rate()){
1546                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1547                         } else {
1548                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1549                         }
1550                         break;
1551                     default:
1552                         break;
1553                 }
1554 
1555                 if (send_cmd){
1556                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1557                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1558                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1559                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1560                     break;
1561                 }
1562                 log_info("Init script done");
1563 
1564                 // Init script download on Broadcom chipsets causes:
1565                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1566                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1567                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1568 
1569                     // - baud rate to reset, restore UART baud rate if needed
1570                     if (need_baud_change) {
1571                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1572                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1573                         hci_stack->hci_transport->set_baudrate(baud_rate);
1574                     }
1575 
1576                     uint16_t bcm_delay_ms = 300;
1577                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1578                     //   -> Work around: wait here.
1579                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1580                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1581                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1582                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1583                     btstack_run_loop_add_timer(&hci_stack->timeout);
1584                     break;
1585                 }
1586             }
1587 #endif
1588             /* fall through */
1589 
1590         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1591             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1592             hci_send_cmd(&hci_read_local_supported_commands);
1593             break;
1594         case HCI_INIT_READ_BD_ADDR:
1595             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1596             hci_send_cmd(&hci_read_bd_addr);
1597             break;
1598         case HCI_INIT_READ_BUFFER_SIZE:
1599             // only read buffer size if supported
1600             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1601                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1602                 hci_send_cmd(&hci_read_buffer_size);
1603                 break;
1604             }
1605 
1606             /* fall through */
1607 
1608         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1609             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1610             hci_send_cmd(&hci_read_local_supported_features);
1611             break;
1612 
1613 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1614         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1615             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1616             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1617             break;
1618         case HCI_INIT_HOST_BUFFER_SIZE:
1619             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1620             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1621                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1622             break;
1623 #endif
1624 
1625         case HCI_INIT_SET_EVENT_MASK:
1626             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1627             if (hci_le_supported()){
1628                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1629             } else {
1630                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1631                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1632             }
1633             break;
1634 
1635 #ifdef ENABLE_CLASSIC
1636         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1637             if (hci_classic_supported() && gap_ssp_supported()){
1638                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1639                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1640                 break;
1641             }
1642 
1643             /* fall through */
1644 
1645         case HCI_INIT_WRITE_INQUIRY_MODE:
1646             if (hci_classic_supported()){
1647                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1648                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1649                 break;
1650             }
1651 
1652             /* fall through */
1653 
1654         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1655             // skip write secure connections host support if not supported or disabled
1656             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1657                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1658                 hci_stack->secure_connections_active = true;
1659                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1660                 break;
1661             }
1662 
1663 #ifdef ENABLE_SCO_OVER_HCI
1664             /* fall through */
1665 
1666         // only sent if ENABLE_SCO_OVER_HCI is defined
1667         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1668             // skip write synchronous flow control if not supported
1669             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1670                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1671                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1672                 break;
1673             }
1674             /* fall through */
1675 
1676         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1677             // skip write default erroneous data reporting if not supported
1678             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1679                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1680                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1681                 break;
1682             }
1683 #endif
1684 
1685 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1686             /* fall through */
1687 
1688         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1689         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1690             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1691                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1692 #ifdef ENABLE_SCO_OVER_HCI
1693                 log_info("BCM: Route SCO data via HCI transport");
1694                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1695 #endif
1696 #ifdef ENABLE_SCO_OVER_PCM
1697                 log_info("BCM: Route SCO data via PCM interface");
1698 #ifdef ENABLE_BCM_PCM_WBS
1699                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1700                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1701 #else
1702                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1703                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1704 #endif
1705 #endif
1706                 break;
1707             }
1708 #endif
1709 
1710 #ifdef ENABLE_SCO_OVER_PCM
1711             /* fall through */
1712 
1713         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1714             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1715                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1716                 log_info("BCM: Config PCM interface for I2S");
1717 #ifdef ENABLE_BCM_PCM_WBS
1718                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1719                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1720 #else
1721                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1722                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1723 #endif
1724                 break;
1725             }
1726 #endif
1727 #endif
1728 
1729 #ifdef ENABLE_BLE
1730             /* fall through */
1731 
1732         // LE INIT
1733         case HCI_INIT_LE_READ_BUFFER_SIZE:
1734             if (hci_le_supported()){
1735                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1736                 hci_send_cmd(&hci_le_read_buffer_size);
1737                 break;
1738             }
1739 
1740             /* fall through */
1741 
1742         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1743             // skip write le host if not supported (e.g. on LE only EM9301)
1744             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1745                 // LE Supported Host = 1, Simultaneous Host = 0
1746                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1747                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1748                 break;
1749             }
1750 
1751             /* fall through */
1752 
1753         case HCI_INIT_LE_SET_EVENT_MASK:
1754             if (hci_le_supported()){
1755                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1756                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1757                 break;
1758             }
1759 #endif
1760 
1761 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1762             /* fall through */
1763 
1764         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1765             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1766                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1767                 hci_send_cmd(&hci_le_read_maximum_data_length);
1768                 break;
1769             }
1770 
1771             /* fall through */
1772 
1773         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1774             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1775                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1776                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1777                 break;
1778             }
1779 #endif
1780 
1781 #ifdef ENABLE_LE_CENTRAL
1782             /* fall through */
1783 
1784         case HCI_INIT_READ_WHITE_LIST_SIZE:
1785             if (hci_le_supported()){
1786                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1787                 hci_send_cmd(&hci_le_read_white_list_size);
1788                 break;
1789             }
1790 
1791             /* fall through */
1792 
1793         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1794             if (hci_le_supported()){
1795                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1796                 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);
1797                 break;
1798             }
1799 #endif
1800 
1801             /* fall through */
1802 
1803         case HCI_INIT_DONE:
1804             hci_stack->substate = HCI_INIT_DONE;
1805 #ifdef ENABLE_CLASSIC
1806             // init sequence complete, check if GAP Tasks are completed
1807             if (hci_stack->gap_tasks != 0) {
1808                 hci_run_gap_tasks_classic();
1809                 break;
1810             }
1811 #endif
1812             hci_init_done();
1813             break;
1814 
1815         default:
1816             return;
1817     }
1818 }
1819 
1820 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1821     bool command_completed = false;
1822     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1823         uint16_t opcode = little_endian_read_16(packet,3);
1824         if (opcode == hci_stack->last_cmd_opcode){
1825             command_completed = true;
1826             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1827         } else {
1828             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1829         }
1830     }
1831 
1832     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1833         uint8_t  status = packet[2];
1834         uint16_t opcode = little_endian_read_16(packet,4);
1835         if (opcode == hci_stack->last_cmd_opcode){
1836             if (status){
1837                 command_completed = true;
1838                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1839             } else {
1840                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1841             }
1842         } else {
1843             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1844         }
1845     }
1846 #ifndef HAVE_HOST_CONTROLLER_API
1847     // Vendor == CSR
1848     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1849         // TODO: track actual command
1850         command_completed = true;
1851     }
1852 
1853     // Vendor == Toshiba
1854     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1855         // TODO: track actual command
1856         command_completed = true;
1857         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1858         hci_stack->num_cmd_packets = 1;
1859     }
1860 #endif
1861 
1862     return command_completed;
1863 }
1864 
1865 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1866 
1867     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1868 
1869     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1870 
1871 #ifndef HAVE_HOST_CONTROLLER_API
1872 
1873     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1874     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1875     //
1876     // HCI Reset
1877     // Timeout 100 ms
1878     // HCI Reset
1879     // Command Complete Reset
1880     // HCI Read Local Version Information
1881     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1882     // hang...
1883     //
1884     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1885     if (!command_completed
1886             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1887             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1888 
1889         uint16_t opcode = little_endian_read_16(packet,3);
1890         if (opcode == hci_reset.opcode){
1891             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1892             return;
1893         }
1894     }
1895 
1896     // CSR & H5
1897     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1898     if (!command_completed
1899             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1900             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1901 
1902         uint16_t opcode = little_endian_read_16(packet,3);
1903         if (opcode == hci_reset.opcode){
1904             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1905             return;
1906         }
1907     }
1908 
1909     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1910     // fix: Correct substate and behave as command below
1911     if (command_completed){
1912         switch (hci_stack->substate){
1913             case HCI_INIT_SEND_RESET:
1914                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1915                 break;
1916             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1917                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1918                 break;
1919             default:
1920                 break;
1921         }
1922     }
1923 
1924 #endif
1925 
1926     if (!command_completed) return;
1927 
1928     bool need_baud_change = false;
1929     bool need_addr_change = false;
1930 
1931 #ifndef HAVE_HOST_CONTROLLER_API
1932     need_baud_change = hci_stack->config
1933                         && hci_stack->chipset
1934                         && hci_stack->chipset->set_baudrate_command
1935                         && hci_stack->hci_transport->set_baudrate
1936                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1937 
1938     need_addr_change = hci_stack->custom_bd_addr_set
1939                         && hci_stack->chipset
1940                         && hci_stack->chipset->set_bd_addr_command;
1941 #endif
1942 
1943     switch(hci_stack->substate){
1944 
1945 #ifndef HAVE_HOST_CONTROLLER_API
1946         case HCI_INIT_SEND_RESET:
1947             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1948             // fix: just correct substate and behave as command below
1949 
1950             /* fall through */
1951 #endif
1952 
1953         case HCI_INIT_W4_SEND_RESET:
1954             btstack_run_loop_remove_timer(&hci_stack->timeout);
1955             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1956             return;
1957 
1958 #ifndef HAVE_HOST_CONTROLLER_API
1959         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1960             // for STLC2500D, baud rate change already happened.
1961             // for others, baud rate gets changed now
1962             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1963                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1964                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1965                 hci_stack->hci_transport->set_baudrate(baud_rate);
1966             }
1967             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1968             return;
1969         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1970             btstack_run_loop_remove_timer(&hci_stack->timeout);
1971             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1972             return;
1973         case HCI_INIT_W4_CUSTOM_INIT:
1974             // repeat custom init
1975             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1976             return;
1977 #endif
1978 
1979         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1980             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1981               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1982                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1983                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1984                 return;
1985             }
1986             if (need_addr_change){
1987                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1988                 return;
1989             }
1990             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1991             return;
1992 #ifndef HAVE_HOST_CONTROLLER_API
1993         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1994             if (need_baud_change){
1995                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1996                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1997                 hci_stack->hci_transport->set_baudrate(baud_rate);
1998             }
1999             if (need_addr_change){
2000                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
2001                 return;
2002             }
2003             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2004             return;
2005         case HCI_INIT_W4_SET_BD_ADDR:
2006             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
2007             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
2008             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2009                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2010                 return;
2011             }
2012             // skipping st warm boot
2013             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2014             return;
2015         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2016             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2017             return;
2018 #endif
2019 
2020         case HCI_INIT_DONE:
2021             // set state if we came here by fall through
2022             hci_stack->substate = HCI_INIT_DONE;
2023             return;
2024 
2025         default:
2026             break;
2027     }
2028     hci_initializing_next_state();
2029 }
2030 
2031 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2032     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2033     bd_addr_t bd_address;
2034     (void)memcpy(&bd_address, conn->address, 6);
2035 
2036 #ifdef ENABLE_CLASSIC
2037     // cache needed data
2038     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2039 #endif
2040 
2041     // connection failed, remove entry
2042     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2043     btstack_memory_hci_connection_free( conn );
2044 
2045 #ifdef ENABLE_CLASSIC
2046     // notify client if dedicated bonding
2047     if (notify_dedicated_bonding_failed){
2048         log_info("hci notify_dedicated_bonding_failed");
2049         hci_emit_dedicated_bonding_result(bd_address, status);
2050     }
2051 
2052     // if authentication error, also delete link key
2053     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2054         gap_drop_link_key_for_bd_addr(bd_address);
2055     }
2056 #else
2057     UNUSED(status);
2058 #endif
2059 }
2060 
2061 #ifdef ENABLE_CLASSIC
2062 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2063     // SSP Controller
2064     if (features[6] & (1 << 3)){
2065         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2066     }
2067     // eSCO
2068     if (features[3] & (1<<7)){
2069         conn->remote_supported_features[0] |= 1;
2070     }
2071     // Extended features
2072     if (features[7] & (1<<7)){
2073         conn->remote_supported_features[0] |= 2;
2074     }
2075 }
2076 
2077 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2078     // SSP Host
2079     if (features[0] & (1 << 0)){
2080         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2081     }
2082     // SC Host
2083     if (features[0] & (1 << 3)){
2084         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2085     }
2086 }
2087 
2088 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2089     // SC Controller
2090     if (features[1] & (1 << 0)){
2091         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2092     }
2093 }
2094 
2095 static void hci_handle_remote_features_received(hci_connection_t * conn){
2096     conn->bonding_flags &= ~BONDING_REMOTE_FEATURES_QUERY_ACTIVE;
2097     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2098     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2099     if (conn->bonding_flags & BONDING_DEDICATED){
2100         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2101     }
2102 }
2103 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2104     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2105     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2106 }
2107 
2108 #endif
2109 
2110 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2111     // handle BT initialization
2112     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2113         hci_initializing_event_handler(packet, size);
2114     }
2115 
2116     // help with BT sleep
2117     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2118         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2119         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2120         hci_initializing_next_state();
2121     }
2122 }
2123 
2124 #ifdef ENABLE_CLASSIC
2125 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2126     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2127     conn->encryption_key_size = encryption_key_size;
2128 
2129     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2130         conn->requested_security_level = LEVEL_0;
2131         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2132         return;
2133     }
2134 
2135     // Request remote features if not already done
2136     if ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) == 0) {
2137         conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2138     }
2139 
2140     // Request Authentication if not already done
2141     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2142     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2143 }
2144 #endif
2145 
2146 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2147     UNUSED(size);
2148 
2149     uint16_t manufacturer;
2150 #ifdef ENABLE_CLASSIC
2151     hci_con_handle_t handle;
2152     hci_connection_t * conn;
2153     uint8_t status;
2154 #endif
2155     // get num cmd packets - limit to 1 to reduce complexity
2156     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2157 
2158     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2159     switch (opcode){
2160         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2161             if (packet[5]) break;
2162             // terminate, name 248 chars
2163             packet[6+248] = 0;
2164             log_info("local name: %s", &packet[6]);
2165             break;
2166         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2167             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2168             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2169                 uint16_t acl_len = little_endian_read_16(packet, 6);
2170                 uint16_t sco_len = packet[8];
2171 
2172                 // determine usable ACL/SCO payload size
2173                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2174                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2175 
2176                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2177                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2178 
2179                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2180                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2181                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2182             }
2183             break;
2184         case HCI_OPCODE_HCI_READ_RSSI:
2185             if (packet[5] == ERROR_CODE_SUCCESS){
2186                 uint8_t event[5];
2187                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2188                 event[1] = 3;
2189                 (void)memcpy(&event[2], &packet[6], 3);
2190                 hci_emit_event(event, sizeof(event), 1);
2191             }
2192             break;
2193 #ifdef ENABLE_BLE
2194         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2195             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2196             hci_stack->le_acl_packets_total_num = packet[8];
2197             // determine usable ACL payload size
2198             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2199                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2200             }
2201             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2202             break;
2203 #endif
2204 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2205         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2206             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2207             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2208             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);
2209             break;
2210 #endif
2211 #ifdef ENABLE_LE_CENTRAL
2212         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2213             hci_stack->le_whitelist_capacity = packet[6];
2214             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2215             break;
2216 #endif
2217         case HCI_OPCODE_HCI_READ_BD_ADDR:
2218             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2219             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));
2220 #ifdef ENABLE_CLASSIC
2221             if (hci_stack->link_key_db){
2222                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2223             }
2224 #endif
2225             break;
2226 #ifdef ENABLE_CLASSIC
2227         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2228             hci_emit_discoverable_enabled(hci_stack->discoverable);
2229             break;
2230         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2231             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2232                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2233                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2234                 hci_emit_event(event, sizeof(event), 1);
2235             }
2236             break;
2237 #endif
2238         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2239             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2240 
2241 #ifdef ENABLE_CLASSIC
2242             // determine usable ACL packet types based on host buffer size and supported features
2243             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2244             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2245 #endif
2246             // Classic/LE
2247             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2248             break;
2249         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2250             manufacturer = little_endian_read_16(packet, 10);
2251             // map Cypress to Broadcom
2252             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2253                 log_info("Treat Cypress as Broadcom");
2254                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2255                 little_endian_store_16(packet, 10, manufacturer);
2256             }
2257             hci_stack->manufacturer = manufacturer;
2258             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2259             break;
2260         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2261             hci_stack->local_supported_commands[0] =
2262                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2263                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2264                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2265                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2266                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2267                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2268                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2269                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2270             hci_stack->local_supported_commands[1] =
2271                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2272                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2273                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2274                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2275                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2276             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2277             break;
2278 #ifdef ENABLE_CLASSIC
2279         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2280             if (packet[5]) return;
2281             hci_stack->synchronous_flow_control_enabled = 1;
2282             break;
2283         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2284             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2285             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2286             conn   = hci_connection_for_handle(handle);
2287             if (conn != NULL) {
2288                 uint8_t key_size = 0;
2289                 if (status == 0){
2290                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2291                     log_info("Handle %04x key Size: %u", handle, key_size);
2292                 } else {
2293                     key_size = 1;
2294                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2295                 }
2296                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2297             }
2298             break;
2299         // assert pairing complete event is emitted.
2300         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2301         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2302         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2303         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2304             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2305             // lookup connection by gap pairing addr
2306             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2307             if (conn == NULL) break;
2308             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2309             break;
2310 
2311 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2312         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2313         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2314             uint8_t event[67];
2315             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2316             event[1] = 65;
2317             (void)memset(&event[2], 0, 65);
2318             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2319                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2320                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2321                     event[2] = 3;
2322                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2323                 } else {
2324                     event[2] = 1;
2325                 }
2326             }
2327             hci_emit_event(event, sizeof(event), 0);
2328             break;
2329         }
2330 
2331         // note: only needed if user does not provide OOB data
2332         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2333             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2334             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2335             if (conn == NULL) break;
2336             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2337             break;
2338 #endif
2339 #endif
2340         default:
2341             break;
2342     }
2343 }
2344 
2345 #ifdef ENABLE_BLE
2346 static void event_handle_le_connection_complete(const uint8_t * packet){
2347 	bd_addr_t addr;
2348 	bd_addr_type_t addr_type;
2349 	hci_connection_t * conn;
2350 
2351 	// Connection management
2352 	reverse_bd_addr(&packet[8], addr);
2353 	addr_type = (bd_addr_type_t)packet[7];
2354 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2355 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2356 
2357 #ifdef ENABLE_LE_CENTRAL
2358 	// handle error: error is reported only to the initiator -> outgoing connection
2359 	if (packet[3]){
2360 
2361 		// handle cancelled outgoing connection
2362 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2363 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2364 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2365 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2366 		    // reset state
2367             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2368             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2369 			// get outgoing connection conn struct for direct connect
2370 			conn = gap_get_outgoing_connection();
2371 		}
2372 
2373 		// outgoing le connection establishment is done
2374 		if (conn){
2375 			// remove entry
2376 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2377 			btstack_memory_hci_connection_free( conn );
2378 		}
2379 		return;
2380 	}
2381 #endif
2382 
2383 	// on success, both hosts receive connection complete event
2384 	if (packet[6] == HCI_ROLE_MASTER){
2385 #ifdef ENABLE_LE_CENTRAL
2386 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2387 		// note: no hci_connection_t object exists yet for connect with whitelist
2388 		if (hci_is_le_connection_type(addr_type)){
2389 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2390 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2391 		}
2392 #endif
2393 	} else {
2394 #ifdef ENABLE_LE_PERIPHERAL
2395 		// if we're slave, it was an incoming connection, advertisements have stopped
2396 		hci_stack->le_advertisements_active = false;
2397 #endif
2398 	}
2399 
2400 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2401 	if (!conn){
2402 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2403 	}
2404 
2405 	// no memory, sorry.
2406 	if (!conn){
2407 		return;
2408 	}
2409 
2410 	conn->state = OPEN;
2411 	conn->role  = packet[6];
2412 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2413 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2414 
2415 #ifdef ENABLE_LE_PERIPHERAL
2416 	if (packet[6] == HCI_ROLE_SLAVE){
2417 		hci_update_advertisements_enabled_for_current_roles();
2418 	}
2419 #endif
2420 
2421     // init unenhanced att bearer mtu
2422     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2423     conn->att_connection.mtu_exchanged = false;
2424 
2425     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2426 
2427 	// restart timer
2428 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2429 	// btstack_run_loop_add_timer(&conn->timeout);
2430 
2431 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2432 
2433 	hci_emit_nr_connections_changed();
2434 }
2435 #endif
2436 
2437 #ifdef ENABLE_CLASSIC
2438 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){
2439     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2440     // LEVEL_4 is tested by l2cap
2441     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2442     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2443     if (level >= LEVEL_3){
2444         // MITM not possible without keyboard or display
2445         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2446         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2447 
2448         // MITM possible if one side has keyboard and the other has keyboard or display
2449         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2450         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2451 
2452         // MITM not possible if one side has only display and other side has no keyboard
2453         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2454         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2455     }
2456     // LEVEL 2 requires SSP, which is a given
2457     return true;
2458 }
2459 
2460 static bool btstack_is_null(uint8_t * data, uint16_t size){
2461     uint16_t i;
2462     for (i=0; i < size ; i++){
2463         if (data[i] != 0) {
2464             return false;
2465         }
2466     }
2467     return true;
2468 }
2469 
2470 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2471     // get requested security level
2472     gap_security_level_t requested_security_level = conn->requested_security_level;
2473     if (hci_stack->gap_secure_connections_only_mode){
2474         requested_security_level = LEVEL_4;
2475     }
2476 
2477     // assess security: LEVEL 4 requires SC
2478     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2479     if ((requested_security_level == LEVEL_4) &&
2480         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2481         !hci_remote_sc_enabled(conn)){
2482         log_info("Level 4 required, but SC not supported -> abort");
2483         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2484         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2485         return;
2486     }
2487 
2488     // assess security based on io capabilities
2489     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2490         // responder: fully validate io caps of both sides as well as OOB data
2491         bool security_possible = false;
2492         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2493 
2494 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2495         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2496         // so we merge the OOB data availability
2497         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2498         if (conn->classic_oob_c_192 != NULL){
2499             have_oob_data |= 1;
2500         }
2501         if (conn->classic_oob_c_256 != NULL){
2502             have_oob_data |= 2;
2503         }
2504         // for up to Level 3, either P-192 as well as P-256 will do
2505         // 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
2506         // if remote does not SC, we should not receive P-256 data either
2507         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2508             security_possible = true;
2509         }
2510         // for Level 4, P-256 is needed
2511         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2512             security_possible = true;
2513         }
2514 #endif
2515 
2516         if (security_possible == false){
2517             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2518             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2519             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2520             return;
2521         }
2522     } else {
2523         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2524 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2525 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2526         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2527             log_info("Level 3+ required, but no input/output -> abort");
2528             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2529             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2530             return;
2531         }
2532 #endif
2533 #endif
2534     }
2535 
2536 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2537     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2538         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2539     } else {
2540         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2541     }
2542 #endif
2543 }
2544 
2545 #endif
2546 
2547 static void event_handler(uint8_t *packet, uint16_t size){
2548 
2549     uint16_t event_length = packet[1];
2550 
2551     // assert packet is complete
2552     if (size != (event_length + 2u)){
2553         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2554         return;
2555     }
2556 
2557     bd_addr_type_t addr_type;
2558     hci_con_handle_t handle;
2559     hci_connection_t * conn;
2560     int i;
2561     int create_connection_cmd;
2562 
2563 #ifdef ENABLE_CLASSIC
2564     hci_link_type_t link_type;
2565     bd_addr_t addr;
2566 #endif
2567 
2568     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2569 
2570     switch (hci_event_packet_get_type(packet)) {
2571 
2572         case HCI_EVENT_COMMAND_COMPLETE:
2573             handle_command_complete_event(packet, size);
2574             break;
2575 
2576         case HCI_EVENT_COMMAND_STATUS:
2577             // get num cmd packets - limit to 1 to reduce complexity
2578             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2579 
2580             // check command status to detected failed outgoing connections
2581             create_connection_cmd = 0;
2582 #ifdef ENABLE_CLASSIC
2583             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2584                 create_connection_cmd = 1;
2585             }
2586 #endif
2587 #ifdef ENABLE_LE_CENTRAL
2588             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2589                 create_connection_cmd = 1;
2590             }
2591 #endif
2592             if (create_connection_cmd) {
2593                 uint8_t status = hci_event_command_status_get_status(packet);
2594                 addr_type = hci_stack->outgoing_addr_type;
2595                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2596                 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);
2597 
2598                 // reset outgoing address info
2599                 memset(hci_stack->outgoing_addr, 0, 6);
2600                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2601 
2602                 // on error
2603                 if (status != ERROR_CODE_SUCCESS){
2604 #ifdef ENABLE_LE_CENTRAL
2605                     if (hci_is_le_connection_type(addr_type)){
2606                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2607                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2608                     }
2609 #endif
2610                     // error => outgoing connection failed
2611                     if (conn != NULL){
2612                         hci_handle_connection_failed(conn, status);
2613                     }
2614                 }
2615             }
2616 
2617 #ifdef ENABLE_CLASSIC
2618             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2619                 uint8_t status = hci_event_command_status_get_status(packet);
2620                 log_info("command status (inquiry), status %x", status);
2621                 if (status == ERROR_CODE_SUCCESS) {
2622                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2623                 } else {
2624                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2625                 }
2626             }
2627 #endif
2628             break;
2629 
2630         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2631             if (size < 3) return;
2632             uint16_t num_handles = packet[2];
2633             if (size != (3u + num_handles * 4u)) return;
2634             uint16_t offset = 3;
2635             for (i=0; i<num_handles;i++){
2636                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2637                 offset += 2u;
2638                 uint16_t num_packets = little_endian_read_16(packet, offset);
2639                 offset += 2u;
2640 
2641                 conn = hci_connection_for_handle(handle);
2642                 if (!conn){
2643                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2644                     continue;
2645                 }
2646 
2647                 if (conn->num_packets_sent >= num_packets){
2648                     conn->num_packets_sent -= num_packets;
2649                 } else {
2650                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2651                     conn->num_packets_sent = 0;
2652                 }
2653                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2654 
2655 #ifdef ENABLE_CLASSIC
2656                 // For SCO, we do the can_send_now_check here
2657                 hci_notify_if_sco_can_send_now();
2658 #endif
2659             }
2660             break;
2661         }
2662 
2663 #ifdef ENABLE_CLASSIC
2664         case HCI_EVENT_INQUIRY_COMPLETE:
2665             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2666                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2667                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2668                 hci_emit_event(event, sizeof(event), 1);
2669             }
2670             break;
2671         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2672             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2673                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2674             }
2675             break;
2676         case HCI_EVENT_CONNECTION_REQUEST:
2677             reverse_bd_addr(&packet[2], addr);
2678             link_type = (hci_link_type_t) packet[11];
2679 
2680             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2681             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2682                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2683                 bd_addr_copy(hci_stack->decline_addr, addr);
2684                 break;
2685             }
2686 
2687             if (hci_stack->gap_classic_accept_callback != NULL){
2688                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2689                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2690                     bd_addr_copy(hci_stack->decline_addr, addr);
2691                     break;
2692                 }
2693             }
2694 
2695             // TODO: eval COD 8-10
2696             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2697             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2698             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2699             if (!conn) {
2700                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2701             }
2702             if (!conn) {
2703                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2704                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2705                 bd_addr_copy(hci_stack->decline_addr, addr);
2706                 break;
2707             }
2708             conn->role  = HCI_ROLE_SLAVE;
2709             conn->state = RECEIVED_CONNECTION_REQUEST;
2710             // store info about eSCO
2711             if (link_type == HCI_LINK_TYPE_ESCO){
2712                 conn->remote_supported_features[0] |= 1;
2713             }
2714             hci_run();
2715             break;
2716 
2717         case HCI_EVENT_CONNECTION_COMPLETE:
2718             // Connection management
2719             reverse_bd_addr(&packet[5], addr);
2720             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2721             addr_type = BD_ADDR_TYPE_ACL;
2722             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2723             if (conn) {
2724                 if (!packet[2]){
2725                     conn->state = OPEN;
2726                     conn->con_handle = little_endian_read_16(packet, 3);
2727 
2728                     // queue set supervision timeout if we're master
2729                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2730                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2731                     }
2732 
2733                     // restart timer
2734                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2735                     btstack_run_loop_add_timer(&conn->timeout);
2736 
2737                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2738 
2739                     hci_emit_nr_connections_changed();
2740                 } else {
2741                     // connection failed
2742                     hci_handle_connection_failed(conn, packet[2]);
2743                 }
2744             }
2745             break;
2746 
2747         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2748             reverse_bd_addr(&packet[5], addr);
2749             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2750             if (packet[2]){
2751                 // connection failed
2752                 break;
2753             }
2754             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2755             if (!conn) {
2756                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2757             }
2758             if (!conn) {
2759                 break;
2760             }
2761             conn->state = OPEN;
2762             conn->con_handle = little_endian_read_16(packet, 3);
2763 
2764 #ifdef ENABLE_SCO_OVER_HCI
2765             // update SCO
2766             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2767                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2768             }
2769             // trigger can send now
2770             if (hci_have_usb_transport()){
2771                 hci_stack->sco_can_send_now = true;
2772             }
2773 #endif
2774 #ifdef HAVE_SCO_TRANSPORT
2775             // configure sco transport
2776             if (hci_stack->sco_transport != NULL){
2777                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2778                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2779             }
2780 #endif
2781             break;
2782 
2783         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2784             handle = little_endian_read_16(packet, 3);
2785             conn = hci_connection_for_handle(handle);
2786             if (!conn) break;
2787             if (!packet[2]){
2788                 const uint8_t * features = &packet[5];
2789                 hci_handle_remote_features_page_0(conn, features);
2790 
2791                 // read extended features if possible
2792                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2793                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2794                     break;
2795                 }
2796             }
2797             hci_handle_remote_features_received(conn);
2798             break;
2799 
2800         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2801             handle = little_endian_read_16(packet, 3);
2802             conn = hci_connection_for_handle(handle);
2803             if (!conn) break;
2804             // status = ok, page = 1
2805             if (!packet[2]) {
2806                 uint8_t page_number = packet[5];
2807                 uint8_t maximum_page_number = packet[6];
2808                 const uint8_t * features = &packet[7];
2809                 bool done = false;
2810                 switch (page_number){
2811                     case 1:
2812                         hci_handle_remote_features_page_1(conn, features);
2813                         if (maximum_page_number >= 2){
2814                             // get Secure Connections (Controller) from Page 2 if available
2815                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2816                         } else {
2817                             // otherwise, assume SC (Controller) == SC (Host)
2818                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2819                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2820                             }
2821                             done = true;
2822                         }
2823                         break;
2824                     case 2:
2825                         hci_handle_remote_features_page_2(conn, features);
2826                         done = true;
2827                         break;
2828                     default:
2829                         break;
2830                 }
2831                 if (!done) break;
2832             }
2833             hci_handle_remote_features_received(conn);
2834             break;
2835 
2836         case HCI_EVENT_LINK_KEY_REQUEST:
2837 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2838             hci_event_link_key_request_get_bd_addr(packet, addr);
2839             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2840             if (!conn) break;
2841 
2842             // lookup link key in db if not cached
2843             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2844                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2845             }
2846 
2847             // response sent by hci_run()
2848             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2849 #endif
2850             break;
2851 
2852         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2853             hci_event_link_key_request_get_bd_addr(packet, addr);
2854             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2855             if (!conn) break;
2856 
2857             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2858 
2859             // CVE-2020-26555: ignore NULL link key
2860             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2861             if (btstack_is_null(&packet[8], 16)) break;
2862 
2863             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2864             // Change Connection Encryption keeps link key type
2865             if (link_key_type != CHANGED_COMBINATION_KEY){
2866                 conn->link_key_type = link_key_type;
2867             }
2868 
2869             // cache link key. link keys stored in little-endian format for legacy reasons
2870             memcpy(&conn->link_key, &packet[8], 16);
2871 
2872             // only store link key:
2873             // - if bondable enabled
2874             if (hci_stack->bondable == false) break;
2875             // - if security level sufficient
2876             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2877             // - for SSP, also check if remote side requested bonding as well
2878             if (conn->link_key_type != COMBINATION_KEY){
2879                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2880                 if (!remote_bonding){
2881                     break;
2882                 }
2883             }
2884             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2885             break;
2886         }
2887 
2888         case HCI_EVENT_PIN_CODE_REQUEST:
2889             hci_event_pin_code_request_get_bd_addr(packet, addr);
2890             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2891             if (!conn) break;
2892 
2893             hci_pairing_started(conn, false);
2894             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2895             if (!hci_stack->bondable ){
2896                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2897                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2898                 hci_run();
2899                 return;
2900             }
2901             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2902             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2903                 log_info("Level 4 required, but SC not supported -> abort");
2904                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2905                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2906                 hci_run();
2907                 return;
2908             }
2909             break;
2910 
2911         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2912             hci_event_io_capability_response_get_bd_addr(packet, addr);
2913             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2914             if (!conn) break;
2915 
2916             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2917             hci_pairing_started(conn, true);
2918             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2919             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2920 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2921             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2922 #endif
2923             break;
2924 
2925         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2926             hci_event_io_capability_response_get_bd_addr(packet, addr);
2927             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2928             if (!conn) break;
2929 
2930             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2931             hci_connection_timestamp(conn);
2932             hci_pairing_started(conn, true);
2933             break;
2934 
2935 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2936         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2937             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2938             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2939             if (!conn) break;
2940 
2941             hci_connection_timestamp(conn);
2942 
2943             hci_pairing_started(conn, true);
2944 
2945             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2946             break;
2947 #endif
2948 
2949         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2950             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2951             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2952             if (!conn) break;
2953             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2954                 if (hci_stack->ssp_auto_accept){
2955                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2956                 };
2957             } else {
2958                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2959                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2960                 // don't forward event to app
2961                 hci_run();
2962                 return;
2963             }
2964             break;
2965 
2966         case HCI_EVENT_USER_PASSKEY_REQUEST:
2967             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2968             if (hci_stack->ssp_auto_accept){
2969                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2970             };
2971             break;
2972 
2973         case HCI_EVENT_MODE_CHANGE:
2974             handle = hci_event_mode_change_get_handle(packet);
2975             conn = hci_connection_for_handle(handle);
2976             if (!conn) break;
2977             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2978             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2979             break;
2980 #endif
2981 
2982         case HCI_EVENT_ENCRYPTION_CHANGE:
2983             handle = hci_event_encryption_change_get_connection_handle(packet);
2984             conn = hci_connection_for_handle(handle);
2985             if (!conn) break;
2986             if (hci_event_encryption_change_get_status(packet) == 0u) {
2987                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2988                 if (encryption_enabled){
2989                     if (hci_is_le_connection(conn)){
2990                         // For LE, we accept connection as encrypted
2991                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2992                     }
2993 #ifdef ENABLE_CLASSIC
2994                     else {
2995 
2996                         // dedicated bonding: send result and disconnect
2997                         if (conn->bonding_flags & BONDING_DEDICATED){
2998                             conn->bonding_flags &= ~BONDING_DEDICATED;
2999                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3000                             conn->bonding_status = packet[2];
3001                             break;
3002                         }
3003 
3004                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3005                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3006                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3007                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3008                             log_info("SC during pairing, but only E0 now -> abort");
3009                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3010                             break;
3011                         }
3012 
3013                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3014                         if (connected_uses_aes_ccm){
3015                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3016                         }
3017 
3018 #ifdef ENABLE_TESTING_SUPPORT
3019                         // work around for issue with PTS dongle
3020                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3021 #endif
3022 
3023                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3024                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3025                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3026                         } else {
3027                             // if not, pretend everything is perfect
3028                             hci_handle_read_encryption_key_size_complete(conn, 16);
3029                         }
3030                     }
3031 #endif
3032                 } else {
3033                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3034                 }
3035             }
3036 
3037             break;
3038 
3039 #ifdef ENABLE_CLASSIC
3040         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3041             handle = hci_event_authentication_complete_get_connection_handle(packet);
3042             conn = hci_connection_for_handle(handle);
3043             if (!conn) break;
3044 
3045             // clear authentication active flag
3046             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3047             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3048 
3049             // authenticated only if auth status == 0
3050             if (hci_event_authentication_complete_get_status(packet) == 0){
3051                 // authenticated
3052                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3053 
3054                 // If not already encrypted, start encryption
3055                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3056                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3057                     break;
3058                 }
3059             }
3060 
3061             // emit updated security level
3062             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3063             break;
3064 
3065         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3066             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3067             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3068             if (!conn) break;
3069 
3070             // treat successfully paired connection as authenticated
3071             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3072                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3073             }
3074 
3075             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3076             break;
3077 #endif
3078 
3079         // HCI_EVENT_DISCONNECTION_COMPLETE
3080         // has been split, to first notify stack before shutting connection down
3081         // see end of function, too.
3082         case HCI_EVENT_DISCONNECTION_COMPLETE:
3083             if (packet[2]) break;   // status != 0
3084             handle = little_endian_read_16(packet, 3);
3085             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3086             if (hci_stack->acl_fragmentation_total_size > 0u) {
3087                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3088                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3089                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3090                     hci_stack->acl_fragmentation_total_size = 0;
3091                     hci_stack->acl_fragmentation_pos = 0;
3092                     if (release_buffer){
3093                         hci_release_packet_buffer();
3094                     }
3095                 }
3096             }
3097 
3098             conn = hci_connection_for_handle(handle);
3099             if (!conn) break;
3100 #ifdef ENABLE_CLASSIC
3101             // pairing failed if it was ongoing
3102             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3103 #endif
3104 
3105             // emit dedicatd bonding event
3106             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3107                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3108             }
3109 
3110             // mark connection for shutdown, stop timers, reset state
3111             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3112             hci_connection_stop_timer(conn);
3113             hci_connection_init(conn);
3114 
3115 #ifdef ENABLE_BLE
3116 #ifdef ENABLE_LE_PERIPHERAL
3117             // re-enable advertisements for le connections if active
3118             if (hci_is_le_connection(conn)){
3119                 hci_update_advertisements_enabled_for_current_roles();
3120             }
3121 #endif
3122 #endif
3123             break;
3124 
3125         case HCI_EVENT_HARDWARE_ERROR:
3126             log_error("Hardware Error: 0x%02x", packet[2]);
3127             if (hci_stack->hardware_error_callback){
3128                 (*hci_stack->hardware_error_callback)(packet[2]);
3129             } else {
3130                 // if no special requests, just reboot stack
3131                 hci_power_control_off();
3132                 hci_power_control_on();
3133             }
3134             break;
3135 
3136 #ifdef ENABLE_CLASSIC
3137         case HCI_EVENT_ROLE_CHANGE:
3138             if (packet[2]) break;   // status != 0
3139             reverse_bd_addr(&packet[3], addr);
3140             addr_type = BD_ADDR_TYPE_ACL;
3141             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3142             if (!conn) break;
3143             conn->role = packet[9];
3144             break;
3145 #endif
3146 
3147         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3148             // release packet buffer only for asynchronous transport and if there are not further fragements
3149             if (hci_transport_synchronous()) {
3150                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3151                 return; // instead of break: to avoid re-entering hci_run()
3152             }
3153             hci_stack->acl_fragmentation_tx_active = 0;
3154             if (hci_stack->acl_fragmentation_total_size) break;
3155             hci_release_packet_buffer();
3156 
3157             // L2CAP receives this event via the hci_emit_event below
3158 
3159 #ifdef ENABLE_CLASSIC
3160             // For SCO, we do the can_send_now_check here
3161             hci_notify_if_sco_can_send_now();
3162 #endif
3163             break;
3164 
3165 #ifdef ENABLE_CLASSIC
3166         case HCI_EVENT_SCO_CAN_SEND_NOW:
3167             // For SCO, we do the can_send_now_check here
3168             hci_stack->sco_can_send_now = true;
3169             hci_notify_if_sco_can_send_now();
3170             return;
3171 
3172         // explode inquriy results for easier consumption
3173         case HCI_EVENT_INQUIRY_RESULT:
3174         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3175         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3176             gap_inquiry_explode(packet, size);
3177             break;
3178 #endif
3179 
3180 #ifdef ENABLE_BLE
3181         case HCI_EVENT_LE_META:
3182             switch (packet[2]){
3183 #ifdef ENABLE_LE_CENTRAL
3184                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3185                     // log_info("advertising report received");
3186                     if (!hci_stack->le_scanning_enabled) break;
3187                     le_handle_advertisement_report(packet, size);
3188                     break;
3189 #endif
3190                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3191 					event_handle_le_connection_complete(packet);
3192                     break;
3193 
3194                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3195                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3196                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3197                     conn = hci_connection_for_handle(handle);
3198                     if (!conn) break;
3199                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3200                     break;
3201 
3202                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3203                     // connection
3204                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3205                     conn = hci_connection_for_handle(handle);
3206                     if (conn) {
3207                         // read arguments
3208                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3209                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3210                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3211                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3212 
3213                         // validate against current connection parameter range
3214                         le_connection_parameter_range_t existing_range;
3215                         gap_get_connection_parameter_range(&existing_range);
3216                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3217                         if (update_parameter){
3218                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3219                             conn->le_conn_interval_min = le_conn_interval_min;
3220                             conn->le_conn_interval_max = le_conn_interval_max;
3221                             conn->le_conn_latency = le_conn_latency;
3222                             conn->le_supervision_timeout = le_supervision_timeout;
3223                         } else {
3224                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3225                         }
3226                     }
3227                     break;
3228 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3229                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3230                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3231                     conn = hci_connection_for_handle(handle);
3232                     if (conn) {
3233                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3234                     }
3235                     break;
3236 #endif
3237                 default:
3238                     break;
3239             }
3240             break;
3241 #endif
3242         case HCI_EVENT_VENDOR_SPECIFIC:
3243             // Vendor specific commands often create vendor specific event instead of num completed packets
3244             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3245             switch (hci_stack->manufacturer){
3246                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3247                     hci_stack->num_cmd_packets = 1;
3248                     break;
3249                 default:
3250                     break;
3251             }
3252             break;
3253         default:
3254             break;
3255     }
3256 
3257     handle_event_for_current_stack_state(packet, size);
3258 
3259     // notify upper stack
3260 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3261 
3262     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3263     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3264 		handle = little_endian_read_16(packet, 3);
3265 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3266 		// discard connection if app did not trigger a reconnect in the event handler
3267 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3268 			hci_shutdown_connection(aConn);
3269 		}
3270     }
3271 
3272 	// execute main loop
3273 	hci_run();
3274 }
3275 
3276 #ifdef ENABLE_CLASSIC
3277 
3278 #ifdef ENABLE_SCO_OVER_HCI
3279 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3280 static void sco_schedule_tx(hci_connection_t * conn);
3281 
3282 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3283     log_debug("SCO TX Timeout");
3284     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3285     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3286     if (!conn) return;
3287 
3288     // trigger send
3289     conn->sco_tx_ready = 1;
3290     // extra packet if CVSD but SCO buffer is too short
3291     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3292         conn->sco_tx_ready++;
3293     }
3294     hci_notify_if_sco_can_send_now();
3295 }
3296 
3297 
3298 #define SCO_TX_AFTER_RX_MS (6)
3299 
3300 static void sco_schedule_tx(hci_connection_t * conn){
3301 
3302     uint32_t now = btstack_run_loop_get_time_ms();
3303     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3304     int time_delta_ms = sco_tx_ms - now;
3305 
3306     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3307 
3308     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3309     btstack_run_loop_remove_timer(timer);
3310     btstack_run_loop_set_timer(timer, time_delta_ms);
3311     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3312     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3313     btstack_run_loop_add_timer(timer);
3314 }
3315 #endif
3316 
3317 static void sco_handler(uint8_t * packet, uint16_t size){
3318     // lookup connection struct
3319     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3320     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3321     if (!conn) return;
3322 
3323 #ifdef ENABLE_SCO_OVER_HCI
3324     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3325     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3326         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3327             packet[2] = 0x3c;
3328             memmove(&packet[3], &packet[23], 63);
3329             size = 63;
3330         }
3331     }
3332 
3333     if (hci_have_usb_transport()){
3334         // Nothing to do
3335     } else {
3336         // 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);
3337         if (hci_stack->synchronous_flow_control_enabled == 0){
3338             uint32_t now = btstack_run_loop_get_time_ms();
3339 
3340             if (!conn->sco_rx_valid){
3341                 // ignore first 10 packets
3342                 conn->sco_rx_count++;
3343                 // log_debug("sco rx count %u", conn->sco_rx_count);
3344                 if (conn->sco_rx_count == 10) {
3345                     // use first timestamp as is and pretent it just started
3346                     conn->sco_rx_ms = now;
3347                     conn->sco_rx_valid = 1;
3348                     conn->sco_rx_count = 0;
3349                     sco_schedule_tx(conn);
3350                 }
3351             } else {
3352                 // track expected arrival timme
3353                 conn->sco_rx_count++;
3354                 conn->sco_rx_ms += 7;
3355                 int delta = (int32_t) (now - conn->sco_rx_ms);
3356                 if (delta > 0){
3357                     conn->sco_rx_ms++;
3358                 }
3359                 // log_debug("sco rx %u", conn->sco_rx_ms);
3360                 sco_schedule_tx(conn);
3361             }
3362         }
3363     }
3364 #endif
3365 
3366     // deliver to app
3367     if (hci_stack->sco_packet_handler) {
3368         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3369     }
3370 
3371 #ifdef HAVE_SCO_TRANSPORT
3372     // We can send one packet for each received packet
3373     conn->sco_tx_ready++;
3374     hci_notify_if_sco_can_send_now();
3375 #endif
3376 
3377 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3378     conn->num_packets_completed++;
3379     hci_stack->host_completed_packets = 1;
3380     hci_run();
3381 #endif
3382 }
3383 #endif
3384 
3385 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3386     hci_dump_packet(packet_type, 1, packet, size);
3387     switch (packet_type) {
3388         case HCI_EVENT_PACKET:
3389             event_handler(packet, size);
3390             break;
3391         case HCI_ACL_DATA_PACKET:
3392             acl_handler(packet, size);
3393             break;
3394 #ifdef ENABLE_CLASSIC
3395         case HCI_SCO_DATA_PACKET:
3396             sco_handler(packet, size);
3397             break;
3398 #endif
3399         default:
3400             break;
3401     }
3402 }
3403 
3404 /**
3405  * @brief Add event packet handler.
3406  */
3407 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3408     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3409 }
3410 
3411 /**
3412  * @brief Remove event packet handler.
3413  */
3414 void hci_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){
3415     btstack_linked_list_remove(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3416 }
3417 
3418 /** Register HCI packet handlers */
3419 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3420     hci_stack->acl_packet_handler = handler;
3421 }
3422 
3423 #ifdef ENABLE_CLASSIC
3424 /**
3425  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3426  */
3427 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3428     hci_stack->sco_packet_handler = handler;
3429 }
3430 #endif
3431 
3432 static void hci_state_reset(void){
3433     // no connections yet
3434     hci_stack->connections = NULL;
3435 
3436     // keep discoverable/connectable as this has been requested by the client(s)
3437     // hci_stack->discoverable = 0;
3438     // hci_stack->connectable = 0;
3439     // hci_stack->bondable = 1;
3440     // hci_stack->own_addr_type = 0;
3441 
3442     // buffer is free
3443     hci_stack->hci_packet_buffer_reserved = false;
3444 
3445     // no pending cmds
3446     hci_stack->decline_reason = 0;
3447 
3448     hci_stack->secure_connections_active = false;
3449 
3450 #ifdef ENABLE_CLASSIC
3451     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3452     hci_stack->page_timeout = 0x6000;  // ca. 15 sec
3453 
3454     hci_stack->gap_tasks =
3455             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3456             GAP_TASK_SET_CLASS_OF_DEVICE |
3457             GAP_TASK_SET_LOCAL_NAME |
3458             GAP_TASK_SET_EIR_DATA |
3459             GAP_TASK_WRITE_SCAN_ENABLE |
3460             GAP_TASK_WRITE_PAGE_TIMEOUT;
3461 #endif
3462 
3463 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3464     hci_stack->classic_read_local_oob_data = false;
3465     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3466 #endif
3467 
3468     // LE
3469 #ifdef ENABLE_BLE
3470     memset(hci_stack->le_random_address, 0, 6);
3471     hci_stack->le_random_address_set = 0;
3472 #endif
3473 #ifdef ENABLE_LE_CENTRAL
3474     hci_stack->le_scanning_active  = false;
3475     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3476     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3477     hci_stack->le_whitelist_capacity = 0;
3478 #endif
3479 #ifdef ENABLE_LE_PERIPHERAL
3480     hci_stack->le_advertisements_active = false;
3481     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3482         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3483     }
3484     if (hci_stack->le_advertisements_data != NULL){
3485         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3486     }
3487 #endif
3488 }
3489 
3490 #ifdef ENABLE_CLASSIC
3491 /**
3492  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3493  */
3494 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3495     // store and open remote device db
3496     hci_stack->link_key_db = link_key_db;
3497     if (hci_stack->link_key_db) {
3498         hci_stack->link_key_db->open();
3499     }
3500 }
3501 #endif
3502 
3503 void hci_init(const hci_transport_t *transport, const void *config){
3504 
3505 #ifdef HAVE_MALLOC
3506     if (!hci_stack) {
3507         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3508     }
3509 #else
3510     hci_stack = &hci_stack_static;
3511 #endif
3512     memset(hci_stack, 0, sizeof(hci_stack_t));
3513 
3514     // reference to use transport layer implementation
3515     hci_stack->hci_transport = transport;
3516 
3517     // reference to used config
3518     hci_stack->config = config;
3519 
3520     // setup pointer for outgoing packet buffer
3521     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3522 
3523     // max acl payload size defined in config.h
3524     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3525 
3526     // register packet handlers with transport
3527     transport->register_packet_handler(&packet_handler);
3528 
3529     hci_stack->state = HCI_STATE_OFF;
3530 
3531     // class of device
3532     hci_stack->class_of_device = 0x007a020c; // Smartphone
3533 
3534     // bondable by default
3535     hci_stack->bondable = 1;
3536 
3537 #ifdef ENABLE_CLASSIC
3538     // classic name
3539     hci_stack->local_name = default_classic_name;
3540 
3541     // Master slave policy
3542     hci_stack->master_slave_policy = 1;
3543 
3544     // Allow Role Switch
3545     hci_stack->allow_role_switch = 1;
3546 
3547     // Default / minimum security level = 2
3548     hci_stack->gap_security_level = LEVEL_2;
3549 
3550     // Default Security Mode 4
3551     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3552 
3553     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3554     hci_stack->gap_required_encyrption_key_size = 7;
3555 
3556     // Link Supervision Timeout
3557     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3558 
3559 #endif
3560 
3561     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3562     hci_stack->ssp_enable = 1;
3563     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3564     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3565     hci_stack->ssp_auto_accept = 1;
3566 
3567     // Secure Connections: enable (requires support from Controller)
3568     hci_stack->secure_connections_enable = true;
3569 
3570     // voice setting - signed 16 bit pcm data with CVSD over the air
3571     hci_stack->sco_voice_setting = 0x60;
3572 
3573 #ifdef ENABLE_LE_CENTRAL
3574     // connection parameter to use for outgoing connections
3575     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3576     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3577     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3578     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3579     hci_stack->le_connection_latency      = 4;         // 4
3580     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3581     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3582     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3583 
3584     // default LE Scanning
3585     hci_stack->le_scan_type     =   0x1; // active
3586     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3587     hci_stack->le_scan_window   =  0x30; //  30 ms
3588 #endif
3589 
3590 #ifdef ENABLE_LE_PERIPHERAL
3591     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3592 #endif
3593 
3594     // connection parameter range used to answer connection parameter update requests in l2cap
3595     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3596     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3597     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3598     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3599     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3600     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3601 
3602     hci_state_reset();
3603 }
3604 
3605 void hci_deinit(void){
3606 #ifdef HAVE_MALLOC
3607     if (hci_stack) {
3608         free(hci_stack);
3609     }
3610 #endif
3611     hci_stack = NULL;
3612 
3613 #ifdef ENABLE_CLASSIC
3614     disable_l2cap_timeouts = 0;
3615 #endif
3616 }
3617 
3618 /**
3619  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3620  */
3621 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3622     hci_stack->chipset = chipset_driver;
3623 
3624     // reset chipset driver - init is also called on power_up
3625     if (hci_stack->chipset && hci_stack->chipset->init){
3626         hci_stack->chipset->init(hci_stack->config);
3627     }
3628 }
3629 
3630 /**
3631  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3632  */
3633 void hci_set_control(const btstack_control_t *hardware_control){
3634     // references to used control implementation
3635     hci_stack->control = hardware_control;
3636     // init with transport config
3637     hardware_control->init(hci_stack->config);
3638 }
3639 
3640 void hci_close(void){
3641 
3642 #ifdef ENABLE_CLASSIC
3643     // close remote device db
3644     if (hci_stack->link_key_db) {
3645         hci_stack->link_key_db->close();
3646     }
3647 #endif
3648 
3649     btstack_linked_list_iterator_t lit;
3650     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3651     while (btstack_linked_list_iterator_has_next(&lit)){
3652         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3653         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3654         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3655         hci_shutdown_connection(connection);
3656     }
3657 
3658     hci_power_control(HCI_POWER_OFF);
3659 
3660 #ifdef HAVE_MALLOC
3661     free(hci_stack);
3662 #endif
3663     hci_stack = NULL;
3664 }
3665 
3666 #ifdef HAVE_SCO_TRANSPORT
3667 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3668     hci_stack->sco_transport = sco_transport;
3669     sco_transport->register_packet_handler(&packet_handler);
3670 }
3671 #endif
3672 
3673 #ifdef ENABLE_CLASSIC
3674 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3675     // validate ranage and set
3676     if (encryption_key_size < 7)  return;
3677     if (encryption_key_size > 16) return;
3678     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3679 }
3680 
3681 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3682     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3683         hci_stack->gap_security_mode = security_mode;
3684         return ERROR_CODE_SUCCESS;
3685     } else {
3686         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3687     }
3688 }
3689 
3690 gap_security_mode_t gap_get_security_mode(void){
3691     return hci_stack->gap_security_mode;
3692 }
3693 
3694 void gap_set_security_level(gap_security_level_t security_level){
3695     hci_stack->gap_security_level = security_level;
3696 }
3697 
3698 gap_security_level_t gap_get_security_level(void){
3699     if (hci_stack->gap_secure_connections_only_mode){
3700         return LEVEL_4;
3701     }
3702     return hci_stack->gap_security_level;
3703 }
3704 
3705 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3706     hci_stack->gap_minimal_service_security_level = security_level;
3707 }
3708 
3709 void gap_set_secure_connections_only_mode(bool enable){
3710     hci_stack->gap_secure_connections_only_mode = enable;
3711 }
3712 
3713 bool gap_get_secure_connections_only_mode(void){
3714     return hci_stack->gap_secure_connections_only_mode;
3715 }
3716 #endif
3717 
3718 #ifdef ENABLE_CLASSIC
3719 void gap_set_class_of_device(uint32_t class_of_device){
3720     hci_stack->class_of_device = class_of_device;
3721     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3722     hci_run();
3723 }
3724 
3725 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3726     hci_stack->default_link_policy_settings = default_link_policy_settings;
3727     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3728     hci_run();
3729 }
3730 
3731 void gap_set_allow_role_switch(bool allow_role_switch){
3732     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3733 }
3734 
3735 uint8_t hci_get_allow_role_switch(void){
3736     return  hci_stack->allow_role_switch;
3737 }
3738 
3739 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3740     hci_stack->link_supervision_timeout = link_supervision_timeout;
3741 }
3742 
3743 void hci_disable_l2cap_timeout_check(void){
3744     disable_l2cap_timeouts = 1;
3745 }
3746 #endif
3747 
3748 #ifndef HAVE_HOST_CONTROLLER_API
3749 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3750 void hci_set_bd_addr(bd_addr_t addr){
3751     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3752     hci_stack->custom_bd_addr_set = 1;
3753 }
3754 #endif
3755 
3756 // State-Module-Driver overview
3757 // state                    module  low-level
3758 // HCI_STATE_OFF             off      close
3759 // HCI_STATE_INITIALIZING,   on       open
3760 // HCI_STATE_WORKING,        on       open
3761 // HCI_STATE_HALTING,        on       open
3762 // HCI_STATE_SLEEPING,    off/sleep   close
3763 // HCI_STATE_FALLING_ASLEEP  on       open
3764 
3765 static int hci_power_control_on(void){
3766 
3767     // power on
3768     int err = 0;
3769     if (hci_stack->control && hci_stack->control->on){
3770         err = (*hci_stack->control->on)();
3771     }
3772     if (err){
3773         log_error( "POWER_ON failed");
3774         hci_emit_hci_open_failed();
3775         return err;
3776     }
3777 
3778     // int chipset driver
3779     if (hci_stack->chipset && hci_stack->chipset->init){
3780         hci_stack->chipset->init(hci_stack->config);
3781     }
3782 
3783     // init transport
3784     if (hci_stack->hci_transport->init){
3785         hci_stack->hci_transport->init(hci_stack->config);
3786     }
3787 
3788     // open transport
3789     err = hci_stack->hci_transport->open();
3790     if (err){
3791         log_error( "HCI_INIT failed, turning Bluetooth off again");
3792         if (hci_stack->control && hci_stack->control->off){
3793             (*hci_stack->control->off)();
3794         }
3795         hci_emit_hci_open_failed();
3796         return err;
3797     }
3798     return 0;
3799 }
3800 
3801 static void hci_power_control_off(void){
3802 
3803     log_info("hci_power_control_off");
3804 
3805     // close low-level device
3806     hci_stack->hci_transport->close();
3807 
3808     log_info("hci_power_control_off - hci_transport closed");
3809 
3810     // power off
3811     if (hci_stack->control && hci_stack->control->off){
3812         (*hci_stack->control->off)();
3813     }
3814 
3815     log_info("hci_power_control_off - control closed");
3816 
3817     hci_stack->state = HCI_STATE_OFF;
3818 }
3819 
3820 static void hci_power_control_sleep(void){
3821 
3822     log_info("hci_power_control_sleep");
3823 
3824 #if 0
3825     // don't close serial port during sleep
3826 
3827     // close low-level device
3828     hci_stack->hci_transport->close(hci_stack->config);
3829 #endif
3830 
3831     // sleep mode
3832     if (hci_stack->control && hci_stack->control->sleep){
3833         (*hci_stack->control->sleep)();
3834     }
3835 
3836     hci_stack->state = HCI_STATE_SLEEPING;
3837 }
3838 
3839 static int hci_power_control_wake(void){
3840 
3841     log_info("hci_power_control_wake");
3842 
3843     // wake on
3844     if (hci_stack->control && hci_stack->control->wake){
3845         (*hci_stack->control->wake)();
3846     }
3847 
3848 #if 0
3849     // open low-level device
3850     int err = hci_stack->hci_transport->open(hci_stack->config);
3851     if (err){
3852         log_error( "HCI_INIT failed, turning Bluetooth off again");
3853         if (hci_stack->control && hci_stack->control->off){
3854             (*hci_stack->control->off)();
3855         }
3856         hci_emit_hci_open_failed();
3857         return err;
3858     }
3859 #endif
3860 
3861     return 0;
3862 }
3863 
3864 static void hci_power_transition_to_initializing(void){
3865     // set up state machine
3866     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3867     hci_stack->hci_packet_buffer_reserved = false;
3868     hci_stack->state = HCI_STATE_INITIALIZING;
3869     hci_stack->substate = HCI_INIT_SEND_RESET;
3870 }
3871 
3872 // returns error
3873 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3874     int err;
3875     switch (power_mode){
3876         case HCI_POWER_ON:
3877             err = hci_power_control_on();
3878             if (err != 0) {
3879                 log_error("hci_power_control_on() error %d", err);
3880                 return err;
3881             }
3882             hci_power_transition_to_initializing();
3883             break;
3884         case HCI_POWER_OFF:
3885             // do nothing
3886             break;
3887         case HCI_POWER_SLEEP:
3888             // do nothing (with SLEEP == OFF)
3889             break;
3890         default:
3891             btstack_assert(false);
3892             break;
3893     }
3894     return ERROR_CODE_SUCCESS;
3895 }
3896 
3897 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3898     switch (power_mode){
3899         case HCI_POWER_ON:
3900             // do nothing
3901             break;
3902         case HCI_POWER_OFF:
3903             // no connections yet, just turn it off
3904             hci_power_control_off();
3905             break;
3906         case HCI_POWER_SLEEP:
3907             // no connections yet, just turn it off
3908             hci_power_control_sleep();
3909             break;
3910         default:
3911             btstack_assert(false);
3912             break;
3913     }
3914     return ERROR_CODE_SUCCESS;
3915 }
3916 
3917 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3918     switch (power_mode){
3919         case HCI_POWER_ON:
3920             // do nothing
3921             break;
3922         case HCI_POWER_OFF:
3923             // see hci_run
3924             hci_stack->state = HCI_STATE_HALTING;
3925             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3926             break;
3927         case HCI_POWER_SLEEP:
3928             // see hci_run
3929             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3930             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3931             break;
3932         default:
3933             btstack_assert(false);
3934             break;
3935     }
3936     return ERROR_CODE_SUCCESS;
3937 }
3938 
3939 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3940     switch (power_mode){
3941         case HCI_POWER_ON:
3942             hci_power_transition_to_initializing();
3943             break;
3944         case HCI_POWER_OFF:
3945             // do nothing
3946             break;
3947         case HCI_POWER_SLEEP:
3948             // see hci_run
3949             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3950             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3951             break;
3952         default:
3953             btstack_assert(false);
3954             break;
3955     }
3956     return ERROR_CODE_SUCCESS;
3957 }
3958 
3959 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3960     switch (power_mode){
3961         case HCI_POWER_ON:
3962             hci_power_transition_to_initializing();
3963             break;
3964         case HCI_POWER_OFF:
3965             // see hci_run
3966             hci_stack->state = HCI_STATE_HALTING;
3967             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3968             break;
3969         case HCI_POWER_SLEEP:
3970             // do nothing
3971             break;
3972         default:
3973             btstack_assert(false);
3974             break;
3975     }
3976     return ERROR_CODE_SUCCESS;
3977 }
3978 
3979 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3980     int err;
3981     switch (power_mode){
3982         case HCI_POWER_ON:
3983             err = hci_power_control_wake();
3984             if (err) return err;
3985             hci_power_transition_to_initializing();
3986             break;
3987         case HCI_POWER_OFF:
3988             hci_stack->state = HCI_STATE_HALTING;
3989             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3990             break;
3991         case HCI_POWER_SLEEP:
3992             // do nothing
3993             break;
3994         default:
3995             btstack_assert(false);
3996             break;
3997     }
3998     return ERROR_CODE_SUCCESS;
3999 }
4000 
4001 int hci_power_control(HCI_POWER_MODE power_mode){
4002     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4003     int err = 0;
4004     switch (hci_stack->state){
4005         case HCI_STATE_OFF:
4006             err = hci_power_control_state_off(power_mode);
4007             break;
4008         case HCI_STATE_INITIALIZING:
4009             err = hci_power_control_state_initializing(power_mode);
4010             break;
4011         case HCI_STATE_WORKING:
4012             err = hci_power_control_state_working(power_mode);
4013             break;
4014         case HCI_STATE_HALTING:
4015             err = hci_power_control_state_halting(power_mode);
4016             break;
4017         case HCI_STATE_FALLING_ASLEEP:
4018             err = hci_power_control_state_falling_asleep(power_mode);
4019             break;
4020         case HCI_STATE_SLEEPING:
4021             err = hci_power_control_state_sleeping(power_mode);
4022             break;
4023         default:
4024             btstack_assert(false);
4025             break;
4026     }
4027     if (err != 0){
4028         return err;
4029     }
4030 
4031     // create internal event
4032 	hci_emit_state();
4033 
4034 	// trigger next/first action
4035 	hci_run();
4036 
4037     return 0;
4038 }
4039 
4040 
4041 #ifdef ENABLE_CLASSIC
4042 
4043 static void hci_update_scan_enable(void){
4044     // 2 = page scan, 1 = inq scan
4045     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4046     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4047     hci_run();
4048 }
4049 
4050 void gap_discoverable_control(uint8_t enable){
4051     if (enable) enable = 1; // normalize argument
4052 
4053     if (hci_stack->discoverable == enable){
4054         hci_emit_discoverable_enabled(hci_stack->discoverable);
4055         return;
4056     }
4057 
4058     hci_stack->discoverable = enable;
4059     hci_update_scan_enable();
4060 }
4061 
4062 void gap_connectable_control(uint8_t enable){
4063     if (enable) enable = 1; // normalize argument
4064 
4065     // don't emit event
4066     if (hci_stack->connectable == enable) return;
4067 
4068     hci_stack->connectable = enable;
4069     hci_update_scan_enable();
4070 }
4071 #endif
4072 
4073 void gap_local_bd_addr(bd_addr_t address_buffer){
4074     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4075 }
4076 
4077 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4078 static void hci_host_num_completed_packets(void){
4079 
4080     // create packet manually as arrays are not supported and num_commands should not get reduced
4081     hci_reserve_packet_buffer();
4082     uint8_t * packet = hci_get_outgoing_packet_buffer();
4083 
4084     uint16_t size = 0;
4085     uint16_t num_handles = 0;
4086     packet[size++] = 0x35;
4087     packet[size++] = 0x0c;
4088     size++;  // skip param len
4089     size++;  // skip num handles
4090 
4091     // add { handle, packets } entries
4092     btstack_linked_item_t * it;
4093     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4094         hci_connection_t * connection = (hci_connection_t *) it;
4095         if (connection->num_packets_completed){
4096             little_endian_store_16(packet, size, connection->con_handle);
4097             size += 2;
4098             little_endian_store_16(packet, size, connection->num_packets_completed);
4099             size += 2;
4100             //
4101             num_handles++;
4102             connection->num_packets_completed = 0;
4103         }
4104     }
4105 
4106     packet[2] = size - 3;
4107     packet[3] = num_handles;
4108 
4109     hci_stack->host_completed_packets = 0;
4110 
4111     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4112     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4113 
4114     // release packet buffer for synchronous transport implementations
4115     if (hci_transport_synchronous()){
4116         hci_release_packet_buffer();
4117         hci_emit_transport_packet_sent();
4118     }
4119 }
4120 #endif
4121 
4122 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4123     UNUSED(ds);
4124     hci_stack->substate = HCI_HALTING_CLOSE;
4125     // allow packet handlers to defer final shutdown
4126     hci_emit_state();
4127     hci_run();
4128 }
4129 
4130 static bool hci_run_acl_fragments(void){
4131     if (hci_stack->acl_fragmentation_total_size > 0u) {
4132         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4133         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4134         if (connection) {
4135             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4136                 hci_send_acl_packet_fragments(connection);
4137                 return true;
4138             }
4139         } else {
4140             // connection gone -> discard further fragments
4141             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4142             hci_stack->acl_fragmentation_total_size = 0;
4143             hci_stack->acl_fragmentation_pos = 0;
4144         }
4145     }
4146     return false;
4147 }
4148 
4149 #ifdef ENABLE_CLASSIC
4150 static bool hci_run_general_gap_classic(void){
4151 
4152     // assert stack is working and classic is active
4153     if (hci_classic_supported() == false)      return false;
4154     if (hci_stack->state != HCI_STATE_WORKING) return false;
4155 
4156     // decline incoming connections
4157     if (hci_stack->decline_reason){
4158         uint8_t reason = hci_stack->decline_reason;
4159         hci_stack->decline_reason = 0;
4160         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4161         return true;
4162     }
4163 
4164     if (hci_stack->gap_tasks != 0){
4165         hci_run_gap_tasks_classic();
4166         return true;
4167     }
4168 
4169     // start/stop inquiry
4170     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4171         uint8_t duration = hci_stack->inquiry_state;
4172         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4173         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4174         return true;
4175     }
4176     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4177         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4178         hci_send_cmd(&hci_inquiry_cancel);
4179         return true;
4180     }
4181     // remote name request
4182     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4183         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4184         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4185                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4186         return true;
4187     }
4188 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4189     // Local OOB data
4190     if (hci_stack->classic_read_local_oob_data){
4191         hci_stack->classic_read_local_oob_data = false;
4192         if (hci_stack->local_supported_commands[1] & 0x10u){
4193             hci_send_cmd(&hci_read_local_extended_oob_data);
4194         } else {
4195             hci_send_cmd(&hci_read_local_oob_data);
4196         }
4197     }
4198 #endif
4199     // pairing
4200     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4201         uint8_t state = hci_stack->gap_pairing_state;
4202         uint8_t pin_code[16];
4203         switch (state){
4204             case GAP_PAIRING_STATE_SEND_PIN:
4205                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4206                 memset(pin_code, 0, 16);
4207                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4208                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4209                 break;
4210             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4211                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4212                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4213                 break;
4214             case GAP_PAIRING_STATE_SEND_PASSKEY:
4215                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4216                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4217                 break;
4218             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4219                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4220                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4221                 break;
4222             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4223                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4224                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4225                 break;
4226             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4227                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4228                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4229                 break;
4230             default:
4231                 break;
4232         }
4233         return true;
4234     }
4235     return false;
4236 }
4237 #endif
4238 
4239 #ifdef ENABLE_BLE
4240 static bool hci_run_general_gap_le(void){
4241 
4242     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4243 
4244     if (hci_stack->state != HCI_STATE_WORKING) return false;
4245     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4246 
4247 
4248     // Phase 1: collect what to stop
4249 
4250     bool scanning_stop = false;
4251     bool connecting_stop = false;
4252     bool advertising_stop = false;
4253 
4254 #ifndef ENABLE_LE_CENTRAL
4255     UNUSED(scanning_stop);
4256     UNUSED(connecting_stop);
4257 #endif
4258 #ifndef ENABLE_LE_PERIPHERAL
4259     UNUSED(advertising_stop);
4260 #endif
4261 
4262     // check if own address changes
4263     bool random_address_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADDRESS) != 0;
4264 
4265     // check if whitelist needs modification
4266     bool whitelist_modification_pending = false;
4267     btstack_linked_list_iterator_t lit;
4268     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4269     while (btstack_linked_list_iterator_has_next(&lit)){
4270         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4271         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4272             whitelist_modification_pending = true;
4273             break;
4274         }
4275     }
4276     // check if resolving list needs modification
4277     bool resolving_list_modification_pending = false;
4278 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4279     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4280 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4281         resolving_list_modification_pending = true;
4282     }
4283 #endif
4284 
4285 #ifdef ENABLE_LE_CENTRAL
4286     // scanning control
4287     if (hci_stack->le_scanning_active) {
4288         // stop if:
4289         // - parameter change required
4290         // - it's disabled
4291         // - whitelist change required but used for scanning
4292         // - resolving list modified
4293         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4294         if ((hci_stack->le_scanning_param_update) ||
4295             !hci_stack->le_scanning_enabled ||
4296             scanning_uses_whitelist ||
4297             resolving_list_modification_pending){
4298 
4299             scanning_stop = true;
4300         }
4301     }
4302 #endif
4303 
4304 #ifdef ENABLE_LE_CENTRAL
4305     // connecting control
4306     bool connecting_with_whitelist;
4307     switch (hci_stack->le_connecting_state){
4308         case LE_CONNECTING_DIRECT:
4309         case LE_CONNECTING_WHITELIST:
4310             // stop connecting if:
4311             // - connecting uses white and whitelist modification pending
4312             // - if it got disabled
4313             // - resolving list modified
4314             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4315             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4316                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4317                 resolving_list_modification_pending) {
4318 
4319                 connecting_stop = true;
4320             }
4321             break;
4322         default:
4323             break;
4324     }
4325 #endif
4326 
4327 #ifdef ENABLE_LE_PERIPHERAL
4328     // le advertisement control
4329     if (hci_stack->le_advertisements_active){
4330         // stop if:
4331         // - parameter change required
4332         // - random address used in advertising and changes
4333         // - it's disabled
4334         // - whitelist change required but used for advertisement filter policy
4335         // - resolving list modified
4336         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4337         bool advertising_uses_random_address = hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC;
4338         bool advertising_change    = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS)  != 0;
4339         if (advertising_change ||
4340             (advertising_uses_random_address && random_address_change) ||
4341             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4342             (advertising_uses_whitelist && whitelist_modification_pending) ||
4343             resolving_list_modification_pending) {
4344 
4345             advertising_stop = true;
4346         }
4347     }
4348 #endif
4349 
4350 
4351     // Phase 2: stop everything that should be off during modifications
4352 
4353 #ifdef ENABLE_LE_CENTRAL
4354     if (scanning_stop){
4355         hci_stack->le_scanning_active = false;
4356         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4357         return true;
4358     }
4359 #endif
4360 
4361 #ifdef ENABLE_LE_CENTRAL
4362     if (connecting_stop){
4363         hci_send_cmd(&hci_le_create_connection_cancel);
4364         return true;
4365     }
4366 #endif
4367 
4368 #ifdef ENABLE_LE_PERIPHERAL
4369     if (advertising_stop){
4370         hci_stack->le_advertisements_active = false;
4371         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4372         return true;
4373     }
4374 #endif
4375 
4376     // Phase 3: modify
4377 
4378     if (random_address_change){
4379         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
4380         hci_send_cmd(&hci_le_set_random_address, hci_stack->le_random_address);
4381         return true;
4382     }
4383 
4384 #ifdef ENABLE_LE_CENTRAL
4385     if (hci_stack->le_scanning_param_update){
4386         hci_stack->le_scanning_param_update = false;
4387         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4388                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4389         return true;
4390     }
4391 #endif
4392 
4393 #ifdef ENABLE_LE_PERIPHERAL
4394     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4395         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4396         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4397         hci_send_cmd(&hci_le_set_advertising_parameters,
4398                      hci_stack->le_advertisements_interval_min,
4399                      hci_stack->le_advertisements_interval_max,
4400                      hci_stack->le_advertisements_type,
4401                      hci_stack->le_advertisements_own_addr_type,
4402                      hci_stack->le_advertisements_direct_address_type,
4403                      hci_stack->le_advertisements_direct_address,
4404                      hci_stack->le_advertisements_channel_map,
4405                      hci_stack->le_advertisements_filter_policy);
4406         return true;
4407     }
4408     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4409         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4410         uint8_t adv_data_clean[31];
4411         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4412         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4413                      hci_stack->le_advertisements_data_len);
4414         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4415         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4416         return true;
4417     }
4418     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4419         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4420         uint8_t scan_data_clean[31];
4421         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4422         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4423                      hci_stack->le_scan_response_data_len);
4424         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4425         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4426         return true;
4427     }
4428 #endif
4429 
4430 
4431 #ifdef ENABLE_LE_CENTRAL
4432     // if connect with whitelist was active and is not cancelled yet, wait until next time
4433     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4434 #endif
4435 
4436     // LE Whitelist Management
4437     if (whitelist_modification_pending){
4438         // add/remove entries
4439         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4440         while (btstack_linked_list_iterator_has_next(&lit)){
4441             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4442 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4443 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4444 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4445 				return true;
4446 			}
4447             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4448 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4449                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4450                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4451                 return true;
4452             }
4453             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4454 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4455 				btstack_memory_whitelist_entry_free(entry);
4456             }
4457         }
4458     }
4459 
4460 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4461     // LE Resolving List Management
4462     if (resolving_list_supported) {
4463 		uint16_t i;
4464 		switch (hci_stack->le_resolving_list_state) {
4465 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4466 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4467 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4468 				return true;
4469 			case LE_RESOLVING_LIST_READ_SIZE:
4470 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4471 				hci_send_cmd(&hci_le_read_resolving_list_size);
4472 				return true;
4473 			case LE_RESOLVING_LIST_SEND_CLEAR:
4474 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4475 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4476 							  sizeof(hci_stack->le_resolving_list_add_entries));
4477 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4478 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4479 				hci_send_cmd(&hci_le_clear_resolving_list);
4480 				return true;
4481 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4482 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4483 					uint8_t offset = i >> 3;
4484 					uint8_t mask = 1 << (i & 7);
4485 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4486 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4487 					bd_addr_t peer_identity_addreses;
4488 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4489 					sm_key_t peer_irk;
4490 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4491 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4492 
4493 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4494 					// trigger whitelist entry 'update' (work around for controller bug)
4495 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4496 					while (btstack_linked_list_iterator_has_next(&lit)) {
4497 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4498 						if (entry->address_type != peer_identity_addr_type) continue;
4499 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4500 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4501 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4502 					}
4503 #endif
4504 
4505 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4506 								 peer_identity_addreses);
4507 					return true;
4508 				}
4509 
4510 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4511 
4512 				/* fall through */
4513 
4514 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4515 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4516 					uint8_t offset = i >> 3;
4517 					uint8_t mask = 1 << (i & 7);
4518 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4519 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4520 					bd_addr_t peer_identity_addreses;
4521 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4522 					sm_key_t peer_irk;
4523 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4524 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4525 					const uint8_t *local_irk = gap_get_persistent_irk();
4526 					// command uses format specifier 'P' that stores 16-byte value without flip
4527 					uint8_t local_irk_flipped[16];
4528 					uint8_t peer_irk_flipped[16];
4529 					reverse_128(local_irk, local_irk_flipped);
4530 					reverse_128(peer_irk, peer_irk_flipped);
4531 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4532 								 peer_irk_flipped, local_irk_flipped);
4533 					return true;
4534 				}
4535 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4536 				break;
4537 
4538 			default:
4539 				break;
4540 		}
4541 	}
4542     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4543 #endif
4544 
4545     // Phase 4: restore state
4546 
4547 #ifdef ENABLE_LE_CENTRAL
4548     // re-start scanning
4549     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4550         hci_stack->le_scanning_active = true;
4551         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4552         return true;
4553     }
4554 #endif
4555 
4556 #ifdef ENABLE_LE_CENTRAL
4557     // re-start connecting
4558     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4559         bd_addr_t null_addr;
4560         memset(null_addr, 0, 6);
4561         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4562         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4563         hci_send_cmd(&hci_le_create_connection,
4564                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4565                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4566                      1,         // use whitelist
4567                      0,         // peer address type
4568                      null_addr, // peer bd addr
4569                      hci_stack->le_connection_own_addr_type,   // our addr type:
4570                      hci_stack->le_connection_interval_min,    // conn interval min
4571                      hci_stack->le_connection_interval_max,    // conn interval max
4572                      hci_stack->le_connection_latency,         // conn latency
4573                      hci_stack->le_supervision_timeout,        // conn latency
4574                      hci_stack->le_minimum_ce_length,          // min ce length
4575                      hci_stack->le_maximum_ce_length           // max ce length
4576         );
4577         return true;
4578     }
4579 #endif
4580 
4581 #ifdef ENABLE_LE_PERIPHERAL
4582     // re-start advertising
4583     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4584         // check if advertisements should be enabled given
4585         hci_stack->le_advertisements_active = true;
4586         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4587         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4588         return true;
4589     }
4590 #endif
4591 
4592     return false;
4593 }
4594 #endif
4595 
4596 static bool hci_run_general_pending_commands(void){
4597     btstack_linked_item_t * it;
4598     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4599         hci_connection_t * connection = (hci_connection_t *) it;
4600 
4601         switch(connection->state){
4602             case SEND_CREATE_CONNECTION:
4603                 switch(connection->address_type){
4604 #ifdef ENABLE_CLASSIC
4605                     case BD_ADDR_TYPE_ACL:
4606                         log_info("sending hci_create_connection");
4607                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4608                         break;
4609 #endif
4610                     default:
4611 #ifdef ENABLE_BLE
4612 #ifdef ENABLE_LE_CENTRAL
4613                         log_info("sending hci_le_create_connection");
4614                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4615                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4616                         hci_send_cmd(&hci_le_create_connection,
4617                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4618                                      hci_stack->le_connection_scan_window,      // conn scan windows
4619                                      0,         // don't use whitelist
4620                                      connection->address_type, // peer address type
4621                                      connection->address,      // peer bd addr
4622                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4623                                      hci_stack->le_connection_interval_min,    // conn interval min
4624                                      hci_stack->le_connection_interval_max,    // conn interval max
4625                                      hci_stack->le_connection_latency,         // conn latency
4626                                      hci_stack->le_supervision_timeout,        // conn latency
4627                                      hci_stack->le_minimum_ce_length,          // min ce length
4628                                      hci_stack->le_maximum_ce_length          // max ce length
4629                         );
4630                         connection->state = SENT_CREATE_CONNECTION;
4631 #endif
4632 #endif
4633                         break;
4634                 }
4635                 return true;
4636 
4637 #ifdef ENABLE_CLASSIC
4638             case RECEIVED_CONNECTION_REQUEST:
4639                 connection->role  = HCI_ROLE_SLAVE;
4640                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4641                     log_info("sending hci_accept_connection_request");
4642                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4643                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4644                 }
4645                 return true;
4646 #endif
4647 
4648 #ifdef ENABLE_BLE
4649 #ifdef ENABLE_LE_CENTRAL
4650             case SEND_CANCEL_CONNECTION:
4651                 connection->state = SENT_CANCEL_CONNECTION;
4652                 hci_send_cmd(&hci_le_create_connection_cancel);
4653                 return true;
4654 #endif
4655 #endif
4656             case SEND_DISCONNECT:
4657                 connection->state = SENT_DISCONNECT;
4658                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4659                 return true;
4660 
4661             default:
4662                 break;
4663         }
4664 
4665         // no further commands if connection is about to get shut down
4666         if (connection->state == SENT_DISCONNECT) continue;
4667 
4668         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4669             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4670             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4671             return true;
4672         }
4673 
4674 #ifdef ENABLE_CLASSIC
4675 
4676         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4677             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4678             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4679             return true;
4680         }
4681 
4682         // Handling link key request requires remote supported features
4683         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4684             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4685             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4686 
4687             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4688             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4689             if (have_link_key && security_level_sufficient){
4690                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4691             } else {
4692                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4693             }
4694             return true;
4695         }
4696 
4697         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4698             log_info("denying to pin request");
4699             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4700             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4701             return true;
4702         }
4703 
4704         // security assessment requires remote features
4705         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4706             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4707             hci_ssp_assess_security_on_io_cap_request(connection);
4708             // 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
4709         }
4710 
4711         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4712             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4713             // set authentication requirements:
4714             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4715             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4716             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4717             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4718                 authreq |= 1;
4719             }
4720             bool bonding = hci_stack->bondable;
4721             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4722                 // if we have received IO Cap Response, we're in responder role
4723                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4724                 if (bonding && !remote_bonding){
4725                     log_info("Remote not bonding, dropping local flag");
4726                     bonding = false;
4727                 }
4728             }
4729             if (bonding){
4730                 if (connection->bonding_flags & BONDING_DEDICATED){
4731                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4732                 } else {
4733                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4734                 }
4735             }
4736             uint8_t have_oob_data = 0;
4737 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4738             if (connection->classic_oob_c_192 != NULL){
4739                     have_oob_data |= 1;
4740             }
4741             if (connection->classic_oob_c_256 != NULL){
4742                 have_oob_data |= 2;
4743             }
4744 #endif
4745             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4746             return true;
4747         }
4748 
4749         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4750             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4751             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4752             return true;
4753         }
4754 
4755 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4756         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4757             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4758             const uint8_t zero[16] = { 0 };
4759             const uint8_t * r_192 = zero;
4760             const uint8_t * c_192 = zero;
4761             const uint8_t * r_256 = zero;
4762             const uint8_t * c_256 = zero;
4763             // verify P-256 OOB
4764             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4765                 c_256 = connection->classic_oob_c_256;
4766                 if (connection->classic_oob_r_256 != NULL) {
4767                     r_256 = connection->classic_oob_r_256;
4768                 }
4769             }
4770             // verify P-192 OOB
4771             if ((connection->classic_oob_c_192 != NULL)) {
4772                 c_192 = connection->classic_oob_c_192;
4773                 if (connection->classic_oob_r_192 != NULL) {
4774                     r_192 = connection->classic_oob_r_192;
4775                 }
4776             }
4777 
4778             // assess security
4779             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4780             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4781             if (need_level_4 && !can_reach_level_4){
4782                 log_info("Level 4 required, but not possible -> abort");
4783                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4784                 // send oob negative reply
4785                 c_256 = NULL;
4786                 c_192 = NULL;
4787             }
4788 
4789             // Reply
4790             if (c_256 != zero) {
4791                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4792             } else if (c_192 != zero){
4793                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4794             } else {
4795                 hci_stack->classic_oob_con_handle = connection->con_handle;
4796                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4797             }
4798             return true;
4799         }
4800 #endif
4801 
4802         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4803             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4804             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4805             return true;
4806         }
4807 
4808         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4809             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4810             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4811             return true;
4812         }
4813 
4814         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4815             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4816             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4817             return true;
4818         }
4819 
4820         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4821             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4822             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4823             connection->state = SENT_DISCONNECT;
4824             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4825             return true;
4826         }
4827 
4828         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4829             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4830             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4831             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4832             return true;
4833         }
4834 
4835         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4836             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4837             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4838             return true;
4839         }
4840 
4841         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4842             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4843             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4844             return true;
4845         }
4846 
4847         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4848             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4849             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4850             return true;
4851         }
4852 
4853         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4854             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4855             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4856             return true;
4857         }
4858 
4859         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4860             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4861             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4862             return true;
4863         }
4864 #endif
4865 
4866         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4867             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4868 #ifdef ENABLE_CLASSIC
4869             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4870 #endif
4871             if (connection->state != SENT_DISCONNECT){
4872                 connection->state = SENT_DISCONNECT;
4873                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4874                 return true;
4875             }
4876         }
4877 
4878 #ifdef ENABLE_CLASSIC
4879         uint16_t sniff_min_interval;
4880         switch (connection->sniff_min_interval){
4881             case 0:
4882                 break;
4883             case 0xffff:
4884                 connection->sniff_min_interval = 0;
4885                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4886                 return true;
4887             default:
4888                 sniff_min_interval = connection->sniff_min_interval;
4889                 connection->sniff_min_interval = 0;
4890                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4891                 return true;
4892         }
4893 
4894         if (connection->sniff_subrating_max_latency != 0xffff){
4895             uint16_t max_latency = connection->sniff_subrating_max_latency;
4896             connection->sniff_subrating_max_latency = 0;
4897             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4898             return true;
4899         }
4900 
4901         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4902             uint8_t service_type = (uint8_t) connection->qos_service_type;
4903             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4904             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);
4905             return true;
4906         }
4907 
4908         if (connection->request_role != HCI_ROLE_INVALID){
4909             hci_role_t role = connection->request_role;
4910             connection->request_role = HCI_ROLE_INVALID;
4911             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4912             return true;
4913         }
4914 #endif
4915 
4916 #ifdef ENABLE_BLE
4917         switch (connection->le_con_parameter_update_state){
4918             // response to L2CAP CON PARAMETER UPDATE REQUEST
4919             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4920                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4921                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4922                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4923                              0x0000, 0xffff);
4924                 return true;
4925             case CON_PARAMETER_UPDATE_REPLY:
4926                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4927                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4928                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4929                              0x0000, 0xffff);
4930                 return true;
4931             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4932                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4933                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4934                 return true;
4935             default:
4936                 break;
4937         }
4938         if (connection->le_phy_update_all_phys != 0xffu){
4939             uint8_t all_phys = connection->le_phy_update_all_phys;
4940             connection->le_phy_update_all_phys = 0xff;
4941             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);
4942             return true;
4943         }
4944 #endif
4945     }
4946     return false;
4947 }
4948 
4949 static void hci_run(void){
4950 
4951     bool done;
4952 
4953     // send continuation fragments first, as they block the prepared packet buffer
4954     done = hci_run_acl_fragments();
4955     if (done) return;
4956 
4957 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4958     // send host num completed packets next as they don't require num_cmd_packets > 0
4959     if (!hci_can_send_comand_packet_transport()) return;
4960     if (hci_stack->host_completed_packets){
4961         hci_host_num_completed_packets();
4962         return;
4963     }
4964 #endif
4965 
4966     if (!hci_can_send_command_packet_now()) return;
4967 
4968     // global/non-connection oriented commands
4969 
4970 
4971 #ifdef ENABLE_CLASSIC
4972     // general gap classic
4973     done = hci_run_general_gap_classic();
4974     if (done) return;
4975 #endif
4976 
4977 #ifdef ENABLE_BLE
4978     // general gap le
4979     done = hci_run_general_gap_le();
4980     if (done) return;
4981 #endif
4982 
4983     // send pending HCI commands
4984     done = hci_run_general_pending_commands();
4985     if (done) return;
4986 
4987     // stack state sub statemachines
4988     hci_connection_t * connection;
4989     switch (hci_stack->state){
4990         case HCI_STATE_INITIALIZING:
4991             hci_initializing_run();
4992             break;
4993 
4994         case HCI_STATE_HALTING:
4995 
4996             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4997             switch (hci_stack->substate){
4998                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4999                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5000 
5001 #ifdef ENABLE_BLE
5002 #ifdef ENABLE_LE_CENTRAL
5003                     // free whitelist entries
5004                     {
5005                         btstack_linked_list_iterator_t lit;
5006                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5007                         while (btstack_linked_list_iterator_has_next(&lit)){
5008                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5009                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5010                             btstack_memory_whitelist_entry_free(entry);
5011                         }
5012                     }
5013 #endif
5014 #endif
5015                     // close all open connections
5016                     connection =  (hci_connection_t *) hci_stack->connections;
5017                     if (connection){
5018                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5019                         if (!hci_can_send_command_packet_now()) return;
5020 
5021                         // check state
5022                         if (connection->state == SENT_DISCONNECT) return;
5023                         connection->state = SENT_DISCONNECT;
5024 
5025                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5026 
5027                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5028                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5029 
5030                         // ... which would be ignored anyway as we shutdown (free) the connection now
5031                         hci_shutdown_connection(connection);
5032 
5033                         // finally, send the disconnect command
5034                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5035                         return;
5036                     }
5037 
5038                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5039                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5040                         log_info("HCI_STATE_HALTING: wait 50 ms");
5041                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5042                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5043                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5044                         btstack_run_loop_add_timer(&hci_stack->timeout);
5045                         break;
5046                     }
5047 
5048                     /* fall through */
5049 
5050                 case HCI_HALTING_CLOSE:
5051                     log_info("HCI_STATE_HALTING, calling off");
5052 
5053                     // switch mode
5054                     hci_power_control_off();
5055 
5056                     log_info("HCI_STATE_HALTING, emitting state");
5057                     hci_emit_state();
5058                     log_info("HCI_STATE_HALTING, done");
5059                     break;
5060 
5061                 case HCI_HALTING_W4_TIMER:
5062                     // keep waiting
5063 
5064                     break;
5065                 default:
5066                     break;
5067             }
5068 
5069             break;
5070 
5071         case HCI_STATE_FALLING_ASLEEP:
5072             switch(hci_stack->substate) {
5073                 case HCI_FALLING_ASLEEP_DISCONNECT:
5074                     log_info("HCI_STATE_FALLING_ASLEEP");
5075                     // close all open connections
5076                     connection =  (hci_connection_t *) hci_stack->connections;
5077                     if (connection){
5078 
5079                         // send disconnect
5080                         if (!hci_can_send_command_packet_now()) return;
5081 
5082                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5083                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5084 
5085                         // send disconnected event right away - causes higher layer connections to get closed, too.
5086                         hci_shutdown_connection(connection);
5087                         return;
5088                     }
5089 
5090                     if (hci_classic_supported()){
5091                         // disable page and inquiry scan
5092                         if (!hci_can_send_command_packet_now()) return;
5093 
5094                         log_info("HCI_STATE_HALTING, disabling inq scans");
5095                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5096 
5097                         // continue in next sub state
5098                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5099                         break;
5100                     }
5101 
5102                     /* fall through */
5103 
5104                 case HCI_FALLING_ASLEEP_COMPLETE:
5105                     log_info("HCI_STATE_HALTING, calling sleep");
5106                     // switch mode
5107                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5108                     hci_emit_state();
5109                     break;
5110 
5111                 default:
5112                     break;
5113             }
5114             break;
5115 
5116         default:
5117             break;
5118     }
5119 }
5120 
5121 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5122     // house-keeping
5123 
5124 #ifdef ENABLE_CLASSIC
5125     bd_addr_t addr;
5126     hci_connection_t * conn;
5127 #endif
5128 #ifdef ENABLE_LE_CENTRAL
5129     uint8_t initiator_filter_policy;
5130 #endif
5131 
5132     uint16_t opcode = little_endian_read_16(packet, 0);
5133     switch (opcode) {
5134         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5135             hci_stack->loopback_mode = packet[3];
5136             break;
5137 
5138 #ifdef ENABLE_CLASSIC
5139         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5140             reverse_bd_addr(&packet[3], addr);
5141             log_info("Create_connection to %s", bd_addr_to_str(addr));
5142 
5143             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5144             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5145                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5146                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5147             }
5148 
5149             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5150             if (!conn) {
5151                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5152                 if (!conn) {
5153                     // notify client that alloc failed
5154                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5155                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5156                 }
5157                 conn->state = SEND_CREATE_CONNECTION;
5158                 conn->role  = HCI_ROLE_MASTER;
5159             }
5160 
5161             conn->con_handle = HCI_CON_HANDLE_INVALID;
5162             conn->role = HCI_ROLE_INVALID;
5163 
5164             log_info("conn state %u", conn->state);
5165             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5166             switch (conn->state) {
5167                 // if connection active exists
5168                 case OPEN:
5169                     // and OPEN, emit connection complete command
5170                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5171                     // packet not sent to controller
5172                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5173                 case RECEIVED_DISCONNECTION_COMPLETE:
5174                     // create connection triggered in disconnect complete event, let's do it now
5175                     break;
5176                 case SEND_CREATE_CONNECTION:
5177                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5178                     break;
5179                 default:
5180                     // otherwise, just ignore as it is already in the open process
5181                     // packet not sent to controller
5182                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5183             }
5184             conn->state = SENT_CREATE_CONNECTION;
5185 
5186             // track outgoing connection
5187             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5188             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5189             break;
5190 
5191 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5192         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5193             // setup_synchronous_connection? Voice setting at offset 22
5194             // TODO: compare to current setting if sco connection already active
5195             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5196             break;
5197         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5198             // accept_synchronous_connection? Voice setting at offset 18
5199             // TODO: compare to current setting if sco connection already active
5200             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5201             break;
5202 #endif
5203 #endif
5204 
5205 #ifdef ENABLE_BLE
5206 #ifdef ENABLE_LE_CENTRAL
5207         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5208             // white list used?
5209             initiator_filter_policy = packet[7];
5210             switch (initiator_filter_policy) {
5211                 case 0:
5212                     // whitelist not used
5213                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5214                     break;
5215                 case 1:
5216                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5217                     break;
5218                 default:
5219                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5220                     break;
5221             }
5222             // track outgoing connection
5223             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5224             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5225             break;
5226         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5227             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5228             break;
5229 #endif
5230 #endif
5231         default:
5232             break;
5233     }
5234 
5235     hci_stack->num_cmd_packets--;
5236 
5237     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5238     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5239     if (err != 0){
5240         return ERROR_CODE_HARDWARE_FAILURE;
5241     }
5242     return ERROR_CODE_SUCCESS;
5243 }
5244 
5245 // disconnect because of security block
5246 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5247     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5248     if (!connection) return;
5249     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5250 }
5251 
5252 
5253 // Configure Secure Simple Pairing
5254 
5255 #ifdef ENABLE_CLASSIC
5256 
5257 // enable will enable SSP during init
5258 void gap_ssp_set_enable(int enable){
5259     hci_stack->ssp_enable = enable;
5260 }
5261 
5262 static int hci_local_ssp_activated(void){
5263     return gap_ssp_supported() && hci_stack->ssp_enable;
5264 }
5265 
5266 // if set, BTstack will respond to io capability request using authentication requirement
5267 void gap_ssp_set_io_capability(int io_capability){
5268     hci_stack->ssp_io_capability = io_capability;
5269 }
5270 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5271     hci_stack->ssp_authentication_requirement = authentication_requirement;
5272 }
5273 
5274 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5275 void gap_ssp_set_auto_accept(int auto_accept){
5276     hci_stack->ssp_auto_accept = auto_accept;
5277 }
5278 
5279 void gap_secure_connections_enable(bool enable){
5280     hci_stack->secure_connections_enable = enable;
5281 }
5282 
5283 #endif
5284 
5285 // va_list part of hci_send_cmd
5286 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5287     if (!hci_can_send_command_packet_now()){
5288         log_error("hci_send_cmd called but cannot send packet now");
5289         return ERROR_CODE_COMMAND_DISALLOWED;
5290     }
5291 
5292     // for HCI INITIALIZATION
5293     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5294     hci_stack->last_cmd_opcode = cmd->opcode;
5295 
5296     hci_reserve_packet_buffer();
5297     uint8_t * packet = hci_stack->hci_packet_buffer;
5298     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5299     uint8_t status = hci_send_cmd_packet(packet, size);
5300 
5301     // release packet buffer on error or for synchronous transport implementations
5302     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5303         hci_release_packet_buffer();
5304         hci_emit_transport_packet_sent();
5305     }
5306 
5307     return status;
5308 }
5309 
5310 /**
5311  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5312  */
5313 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5314     va_list argptr;
5315     va_start(argptr, cmd);
5316     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5317     va_end(argptr);
5318     return status;
5319 }
5320 
5321 // Create various non-HCI events.
5322 // TODO: generalize, use table similar to hci_create_command
5323 
5324 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5325     // dump packet
5326     if (dump) {
5327         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5328     }
5329 
5330     // dispatch to all event handlers
5331     btstack_linked_list_iterator_t it;
5332     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5333     while (btstack_linked_list_iterator_has_next(&it)){
5334         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5335         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5336     }
5337 }
5338 
5339 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5340     if (!hci_stack->acl_packet_handler) return;
5341     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5342 }
5343 
5344 #ifdef ENABLE_CLASSIC
5345 static void hci_notify_if_sco_can_send_now(void){
5346     // notify SCO sender if waiting
5347     if (!hci_stack->sco_waiting_for_can_send_now) return;
5348     if (hci_can_send_sco_packet_now()){
5349         hci_stack->sco_waiting_for_can_send_now = 0;
5350         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5351         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5352         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5353     }
5354 }
5355 
5356 // parsing end emitting has been merged to reduce code size
5357 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5358     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5359 
5360     uint8_t * eir_data;
5361     ad_context_t context;
5362     const uint8_t * name;
5363     uint8_t         name_len;
5364 
5365     if (size < 3) return;
5366 
5367     int event_type = hci_event_packet_get_type(packet);
5368     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5369     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5370 
5371     switch (event_type){
5372         case HCI_EVENT_INQUIRY_RESULT:
5373         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5374             if (size != (3 + (num_responses * 14))) return;
5375             break;
5376         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5377             if (size != 257) return;
5378             if (num_responses != 1) return;
5379             break;
5380         default:
5381             return;
5382     }
5383 
5384     // event[1] is set at the end
5385     int i;
5386     for (i=0; i<num_responses;i++){
5387         memset(event, 0, sizeof(event));
5388         event[0] = GAP_EVENT_INQUIRY_RESULT;
5389         uint8_t event_size = 27;    // if name is not set by EIR
5390 
5391         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5392         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5393         (void)memcpy(&event[9],
5394                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5395                      3); // class of device
5396         (void)memcpy(&event[12],
5397                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5398                      2); // clock offset
5399 
5400         switch (event_type){
5401             case HCI_EVENT_INQUIRY_RESULT:
5402                 // 14,15,16,17 = 0, size 18
5403                 break;
5404             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5405                 event[14] = 1;
5406                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5407                 // 16,17 = 0, size 18
5408                 break;
5409             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5410                 event[14] = 1;
5411                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5412                 // EIR packets only contain a single inquiry response
5413                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5414                 name = NULL;
5415                 // Iterate over EIR data
5416                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5417                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5418                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5419                     const uint8_t * data = ad_iterator_get_data(&context);
5420                     // Prefer Complete Local Name over Shortened Local Name
5421                     switch (data_type){
5422                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5423                             if (name) continue;
5424                             /* fall through */
5425                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5426                             name = data;
5427                             name_len = data_size;
5428                             break;
5429                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5430                             if (data_size != 8) break;
5431                             event[16] = 1;
5432                             memcpy(&event[17], data, 8);
5433                             break;
5434                         default:
5435                             break;
5436                     }
5437                 }
5438                 if (name){
5439                     event[25] = 1;
5440                     // truncate name if needed
5441                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5442                     event[26] = len;
5443                     (void)memcpy(&event[27], name, len);
5444                     event_size += len;
5445                 }
5446                 break;
5447             default:
5448                 return;
5449         }
5450         event[1] = event_size - 2;
5451         hci_emit_event(event, event_size, 1);
5452     }
5453 }
5454 #endif
5455 
5456 void hci_emit_state(void){
5457     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5458     uint8_t event[3];
5459     event[0] = BTSTACK_EVENT_STATE;
5460     event[1] = sizeof(event) - 2u;
5461     event[2] = hci_stack->state;
5462     hci_emit_event(event, sizeof(event), 1);
5463 }
5464 
5465 #ifdef ENABLE_CLASSIC
5466 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5467     uint8_t event[13];
5468     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5469     event[1] = sizeof(event) - 2;
5470     event[2] = status;
5471     little_endian_store_16(event, 3, con_handle);
5472     reverse_bd_addr(address, &event[5]);
5473     event[11] = 1; // ACL connection
5474     event[12] = 0; // encryption disabled
5475     hci_emit_event(event, sizeof(event), 1);
5476 }
5477 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5478     if (disable_l2cap_timeouts) return;
5479     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5480     uint8_t event[4];
5481     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5482     event[1] = sizeof(event) - 2;
5483     little_endian_store_16(event, 2, conn->con_handle);
5484     hci_emit_event(event, sizeof(event), 1);
5485 }
5486 #endif
5487 
5488 #ifdef ENABLE_BLE
5489 #ifdef ENABLE_LE_CENTRAL
5490 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){
5491     uint8_t event[21];
5492     event[0] = HCI_EVENT_LE_META;
5493     event[1] = sizeof(event) - 2u;
5494     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5495     event[3] = status;
5496     little_endian_store_16(event, 4, con_handle);
5497     event[6] = 0; // TODO: role
5498     event[7] = address_type;
5499     reverse_bd_addr(address, &event[8]);
5500     little_endian_store_16(event, 14, 0); // interval
5501     little_endian_store_16(event, 16, 0); // latency
5502     little_endian_store_16(event, 18, 0); // supervision timeout
5503     event[20] = 0; // master clock accuracy
5504     hci_emit_event(event, sizeof(event), 1);
5505 }
5506 #endif
5507 #endif
5508 
5509 static void hci_emit_transport_packet_sent(void){
5510     // notify upper stack that it might be possible to send again
5511     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5512     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5513 }
5514 
5515 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5516     uint8_t event[6];
5517     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5518     event[1] = sizeof(event) - 2u;
5519     event[2] = 0; // status = OK
5520     little_endian_store_16(event, 3, con_handle);
5521     event[5] = reason;
5522     hci_emit_event(event, sizeof(event), 1);
5523 }
5524 
5525 static void hci_emit_nr_connections_changed(void){
5526     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5527     uint8_t event[3];
5528     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5529     event[1] = sizeof(event) - 2u;
5530     event[2] = nr_hci_connections();
5531     hci_emit_event(event, sizeof(event), 1);
5532 }
5533 
5534 static void hci_emit_hci_open_failed(void){
5535     log_info("BTSTACK_EVENT_POWERON_FAILED");
5536     uint8_t event[2];
5537     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5538     event[1] = sizeof(event) - 2u;
5539     hci_emit_event(event, sizeof(event), 1);
5540 }
5541 
5542 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5543     log_info("hci_emit_dedicated_bonding_result %u ", status);
5544     uint8_t event[9];
5545     int pos = 0;
5546     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5547     event[pos++] = sizeof(event) - 2u;
5548     event[pos++] = status;
5549     reverse_bd_addr(address, &event[pos]);
5550     hci_emit_event(event, sizeof(event), 1);
5551 }
5552 
5553 
5554 #ifdef ENABLE_CLASSIC
5555 
5556 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5557     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5558     uint8_t event[5];
5559     int pos = 0;
5560     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5561     event[pos++] = sizeof(event) - 2;
5562     little_endian_store_16(event, 2, con_handle);
5563     pos += 2;
5564     event[pos++] = level;
5565     hci_emit_event(event, sizeof(event), 1);
5566 }
5567 
5568 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5569     if (!connection) return LEVEL_0;
5570     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5571     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5572     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5573     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5574     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5575     // LEVEL 4 always requires 128 bit encrytion key size
5576     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5577         security_level = LEVEL_3;
5578     }
5579     return security_level;
5580 }
5581 
5582 static void hci_emit_discoverable_enabled(uint8_t enabled){
5583     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5584     uint8_t event[3];
5585     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5586     event[1] = sizeof(event) - 2;
5587     event[2] = enabled;
5588     hci_emit_event(event, sizeof(event), 1);
5589 }
5590 
5591 // query if remote side supports eSCO
5592 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5593     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5594     if (!connection) return false;
5595     return (connection->remote_supported_features[0] & 1) != 0;
5596 }
5597 
5598 static bool hci_ssp_supported(hci_connection_t * connection){
5599     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5600     return (connection->bonding_flags & mask) == mask;
5601 }
5602 
5603 // query if remote side supports SSP
5604 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5605     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5606     if (!connection) return false;
5607     return hci_ssp_supported(connection) ? 1 : 0;
5608 }
5609 
5610 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5611     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5612 }
5613 
5614 /**
5615  * Check if remote supported features query has completed
5616  */
5617 bool hci_remote_features_available(hci_con_handle_t handle){
5618     hci_connection_t * connection = hci_connection_for_handle(handle);
5619     if (!connection) return false;
5620     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5621 }
5622 
5623 /**
5624  * Trigger remote supported features query
5625  */
5626 void hci_remote_features_query(hci_con_handle_t con_handle){
5627     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5628     if (!connection) return;
5629     if ((connection->bonding_flags & (BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_RECEIVED_REMOTE_FEATURES)) != 0) return;
5630     connection->bonding_flags |= BONDING_REMOTE_FEATURES_QUERY_ACTIVE | BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
5631     hci_run();
5632 }
5633 
5634 // GAP API
5635 /**
5636  * @bbrief enable/disable bonding. default is enabled
5637  * @praram enabled
5638  */
5639 void gap_set_bondable_mode(int enable){
5640     hci_stack->bondable = enable ? 1 : 0;
5641 }
5642 /**
5643  * @brief Get bondable mode.
5644  * @return 1 if bondable
5645  */
5646 int gap_get_bondable_mode(void){
5647     return hci_stack->bondable;
5648 }
5649 
5650 /**
5651  * @brief map link keys to security levels
5652  */
5653 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5654     switch (link_key_type){
5655         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5656             return LEVEL_4;
5657         case COMBINATION_KEY:
5658         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5659             return LEVEL_3;
5660         default:
5661             return LEVEL_2;
5662     }
5663 }
5664 
5665 /**
5666  * @brief map link keys to secure connection yes/no
5667  */
5668 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5669     switch (link_key_type){
5670         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5671         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5672             return 1;
5673         default:
5674             return 0;
5675     }
5676 }
5677 
5678 /**
5679  * @brief map link keys to authenticated
5680  */
5681 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5682     switch (link_key_type){
5683         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5684         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5685             return 1;
5686         default:
5687             return 0;
5688     }
5689 }
5690 
5691 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5692     log_info("gap_mitm_protection_required_for_security_level %u", level);
5693     return level > LEVEL_2;
5694 }
5695 
5696 /**
5697  * @brief get current security level
5698  */
5699 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5700     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5701     if (!connection) return LEVEL_0;
5702     return gap_security_level_for_connection(connection);
5703 }
5704 
5705 /**
5706  * @brief request connection to device to
5707  * @result GAP_AUTHENTICATION_RESULT
5708  */
5709 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5710     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5711     if (!connection){
5712         hci_emit_security_level(con_handle, LEVEL_0);
5713         return;
5714     }
5715 
5716     btstack_assert(hci_is_le_connection(connection) == false);
5717 
5718     // Core Spec 5.2, GAP 5.2.2: "When in Secure Connections Only mode, all services (except those allowed to have Security Mode 4, Level 0)
5719     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5720     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5721         requested_level = LEVEL_4;
5722     }
5723 
5724     gap_security_level_t current_level = gap_security_level(con_handle);
5725     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5726         requested_level, connection->requested_security_level, current_level);
5727 
5728     // authentication active if authentication request was sent or planned level > 0
5729     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5730     if (authentication_active){
5731         // authentication already active
5732         if (connection->requested_security_level < requested_level){
5733             // increase requested level as new level is higher
5734             // TODO: handle re-authentication when done
5735             connection->requested_security_level = requested_level;
5736         }
5737     } else {
5738         // no request active, notify if security sufficient
5739         if (requested_level <= current_level){
5740             hci_emit_security_level(con_handle, current_level);
5741             return;
5742         }
5743 
5744         // store request
5745         connection->requested_security_level = requested_level;
5746 
5747         // request remote features if not already active
5748         hci_remote_features_query(con_handle);
5749 
5750         // start to authenticate connection
5751         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5752         hci_run();
5753     }
5754 }
5755 
5756 /**
5757  * @brief start dedicated bonding with device. disconnect after bonding
5758  * @param device
5759  * @param request MITM protection
5760  * @result GAP_DEDICATED_BONDING_COMPLETE
5761  */
5762 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5763 
5764     // create connection state machine
5765     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5766 
5767     if (!connection){
5768         return BTSTACK_MEMORY_ALLOC_FAILED;
5769     }
5770 
5771     // delete linkn key
5772     gap_drop_link_key_for_bd_addr(device);
5773 
5774     // configure LEVEL_2/3, dedicated bonding
5775     connection->state = SEND_CREATE_CONNECTION;
5776     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5777     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5778     connection->bonding_flags = BONDING_DEDICATED;
5779 
5780     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5781 
5782     // handle: connnection failure (connection complete != ok)
5783     // handle: authentication failure
5784     // handle: disconnect on done
5785 
5786     hci_run();
5787 
5788     return 0;
5789 }
5790 
5791 void gap_set_local_name(const char * local_name){
5792     hci_stack->local_name = local_name;
5793     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5794     // also update EIR if not set by user
5795     if (hci_stack->eir_data == NULL){
5796         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5797     }
5798     hci_run();
5799 }
5800 #endif
5801 
5802 
5803 #ifdef ENABLE_BLE
5804 
5805 #ifdef ENABLE_LE_CENTRAL
5806 void gap_start_scan(void){
5807     hci_stack->le_scanning_enabled = true;
5808     hci_run();
5809 }
5810 
5811 void gap_stop_scan(void){
5812     hci_stack->le_scanning_enabled = false;
5813     hci_run();
5814 }
5815 
5816 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5817     hci_stack->le_scan_type          = scan_type;
5818     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5819     hci_stack->le_scan_interval      = scan_interval;
5820     hci_stack->le_scan_window        = scan_window;
5821     hci_stack->le_scanning_param_update = true;
5822     hci_run();
5823 }
5824 
5825 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5826     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5827 }
5828 
5829 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5830     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5831     if (!conn){
5832         // disallow if le connection is already outgoing
5833         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5834             log_error("le connection already active");
5835             return ERROR_CODE_COMMAND_DISALLOWED;
5836         }
5837 
5838         log_info("gap_connect: no connection exists yet, creating context");
5839         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5840         if (!conn){
5841             // notify client that alloc failed
5842             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5843             log_info("gap_connect: failed to alloc hci_connection_t");
5844             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5845         }
5846 
5847         // set le connecting state
5848         if (hci_is_le_connection_type(addr_type)){
5849             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5850         }
5851 
5852         conn->state = SEND_CREATE_CONNECTION;
5853         log_info("gap_connect: send create connection next");
5854         hci_run();
5855         return ERROR_CODE_SUCCESS;
5856     }
5857 
5858     if (!hci_is_le_connection(conn) ||
5859         (conn->state == SEND_CREATE_CONNECTION) ||
5860         (conn->state == SENT_CREATE_CONNECTION)) {
5861         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5862         log_error("gap_connect: classic connection or connect is already being created");
5863         return GATT_CLIENT_IN_WRONG_STATE;
5864     }
5865 
5866     // check if connection was just disconnected
5867     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5868         log_info("gap_connect: send create connection (again)");
5869         conn->state = SEND_CREATE_CONNECTION;
5870         hci_run();
5871         return ERROR_CODE_SUCCESS;
5872     }
5873 
5874     log_info("gap_connect: context exists with state %u", conn->state);
5875     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5876     hci_run();
5877     return ERROR_CODE_SUCCESS;
5878 }
5879 
5880 // @assumption: only a single outgoing LE Connection exists
5881 static hci_connection_t * gap_get_outgoing_connection(void){
5882     btstack_linked_item_t *it;
5883     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5884         hci_connection_t * conn = (hci_connection_t *) it;
5885         if (!hci_is_le_connection(conn)) continue;
5886         switch (conn->state){
5887             case SEND_CREATE_CONNECTION:
5888             case SENT_CREATE_CONNECTION:
5889             case SENT_CANCEL_CONNECTION:
5890                 return conn;
5891             default:
5892                 break;
5893         };
5894     }
5895     return NULL;
5896 }
5897 
5898 uint8_t gap_connect_cancel(void){
5899     hci_connection_t * conn = gap_get_outgoing_connection();
5900     if (!conn) return 0;
5901     switch (conn->state){
5902         case SEND_CREATE_CONNECTION:
5903             // skip sending create connection and emit event instead
5904             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5905             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5906             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5907             btstack_memory_hci_connection_free( conn );
5908             break;
5909         case SENT_CREATE_CONNECTION:
5910             // request to send cancel connection
5911             conn->state = SEND_CANCEL_CONNECTION;
5912             hci_run();
5913             break;
5914         default:
5915             break;
5916     }
5917     return 0;
5918 }
5919 #endif
5920 
5921 #ifdef ENABLE_LE_CENTRAL
5922 /**
5923  * @brief Set connection parameters for outgoing connections
5924  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5925  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5926  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5927  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5928  * @param conn_latency, default: 4
5929  * @param supervision_timeout (unit: 10ms), default: 720 ms
5930  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5931  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5932  */
5933 
5934 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5935     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5936     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5937     hci_stack->le_connection_scan_interval = conn_scan_interval;
5938     hci_stack->le_connection_scan_window = conn_scan_window;
5939     hci_stack->le_connection_interval_min = conn_interval_min;
5940     hci_stack->le_connection_interval_max = conn_interval_max;
5941     hci_stack->le_connection_latency = conn_latency;
5942     hci_stack->le_supervision_timeout = supervision_timeout;
5943     hci_stack->le_minimum_ce_length = min_ce_length;
5944     hci_stack->le_maximum_ce_length = max_ce_length;
5945 }
5946 #endif
5947 
5948 /**
5949  * @brief Updates the connection parameters for a given LE connection
5950  * @param handle
5951  * @param conn_interval_min (unit: 1.25ms)
5952  * @param conn_interval_max (unit: 1.25ms)
5953  * @param conn_latency
5954  * @param supervision_timeout (unit: 10ms)
5955  * @returns 0 if ok
5956  */
5957 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5958     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5959     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5960     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5961     connection->le_conn_interval_min = conn_interval_min;
5962     connection->le_conn_interval_max = conn_interval_max;
5963     connection->le_conn_latency = conn_latency;
5964     connection->le_supervision_timeout = supervision_timeout;
5965     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5966     hci_run();
5967     return 0;
5968 }
5969 
5970 /**
5971  * @brief Request an update of the connection parameter for a given LE connection
5972  * @param handle
5973  * @param conn_interval_min (unit: 1.25ms)
5974  * @param conn_interval_max (unit: 1.25ms)
5975  * @param conn_latency
5976  * @param supervision_timeout (unit: 10ms)
5977  * @returns 0 if ok
5978  */
5979 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5980     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5981     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5982     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5983     connection->le_conn_interval_min = conn_interval_min;
5984     connection->le_conn_interval_max = conn_interval_max;
5985     connection->le_conn_latency = conn_latency;
5986     connection->le_supervision_timeout = supervision_timeout;
5987     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5988     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5989     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5990     return 0;
5991 }
5992 
5993 #ifdef ENABLE_LE_PERIPHERAL
5994 
5995 /**
5996  * @brief Set Advertisement Data
5997  * @param advertising_data_length
5998  * @param advertising_data (max 31 octets)
5999  * @note data is not copied, pointer has to stay valid
6000  */
6001 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
6002     hci_stack->le_advertisements_data_len = advertising_data_length;
6003     hci_stack->le_advertisements_data = advertising_data;
6004     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6005     hci_run();
6006 }
6007 
6008 /**
6009  * @brief Set Scan Response Data
6010  * @param advertising_data_length
6011  * @param advertising_data (max 31 octets)
6012  * @note data is not copied, pointer has to stay valid
6013  */
6014 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6015     hci_stack->le_scan_response_data_len = scan_response_data_length;
6016     hci_stack->le_scan_response_data = scan_response_data;
6017     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6018     hci_run();
6019 }
6020 
6021 /**
6022  * @brief Set Advertisement Parameters
6023  * @param adv_int_min
6024  * @param adv_int_max
6025  * @param adv_type
6026  * @param direct_address_type
6027  * @param direct_address
6028  * @param channel_map
6029  * @param filter_policy
6030  *
6031  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6032  */
6033  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6034     uint8_t direct_address_typ, bd_addr_t direct_address,
6035     uint8_t channel_map, uint8_t filter_policy) {
6036 
6037     hci_stack->le_advertisements_interval_min = adv_int_min;
6038     hci_stack->le_advertisements_interval_max = adv_int_max;
6039     hci_stack->le_advertisements_type = adv_type;
6040     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6041     hci_stack->le_advertisements_channel_map = channel_map;
6042     hci_stack->le_advertisements_filter_policy = filter_policy;
6043     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6044                  6);
6045 
6046     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6047     hci_run();
6048  }
6049 
6050 /**
6051  * @brief Enable/Disable Advertisements
6052  * @param enabled
6053  */
6054 void gap_advertisements_enable(int enabled){
6055     hci_stack->le_advertisements_enabled = enabled != 0;
6056     hci_update_advertisements_enabled_for_current_roles();
6057     hci_run();
6058 }
6059 
6060 #endif
6061 
6062 void hci_le_set_own_address_type(uint8_t own_address_type){
6063     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6064     if (own_address_type == hci_stack->le_own_addr_type) return;
6065     hci_stack->le_own_addr_type = own_address_type;
6066 
6067 #ifdef ENABLE_LE_PERIPHERAL
6068     // update advertisement parameters, too
6069     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6070     hci_run();
6071 #endif
6072 #ifdef ENABLE_LE_CENTRAL
6073     // note: we don't update scan parameters or modify ongoing connection attempts
6074 #endif
6075 }
6076 
6077 void hci_le_random_address_set(const bd_addr_t random_address){
6078     memcpy(hci_stack->le_random_address, random_address, 6);
6079     hci_stack->le_random_address_set = true;
6080     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADDRESS;
6081     hci_run();
6082 }
6083 
6084 #endif
6085 
6086 uint8_t gap_disconnect(hci_con_handle_t handle){
6087     hci_connection_t * conn = hci_connection_for_handle(handle);
6088     if (!conn){
6089         hci_emit_disconnection_complete(handle, 0);
6090         return 0;
6091     }
6092     // ignore if already disconnected
6093     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6094         return 0;
6095     }
6096     conn->state = SEND_DISCONNECT;
6097     hci_run();
6098     return 0;
6099 }
6100 
6101 int gap_read_rssi(hci_con_handle_t con_handle){
6102     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6103     if (hci_connection == NULL) return 0;
6104     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6105     hci_run();
6106     return 1;
6107 }
6108 
6109 /**
6110  * @brief Get connection type
6111  * @param con_handle
6112  * @result connection_type
6113  */
6114 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6115     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6116     if (!conn) return GAP_CONNECTION_INVALID;
6117     switch (conn->address_type){
6118         case BD_ADDR_TYPE_LE_PUBLIC:
6119         case BD_ADDR_TYPE_LE_RANDOM:
6120             return GAP_CONNECTION_LE;
6121         case BD_ADDR_TYPE_SCO:
6122             return GAP_CONNECTION_SCO;
6123         case BD_ADDR_TYPE_ACL:
6124             return GAP_CONNECTION_ACL;
6125         default:
6126             return GAP_CONNECTION_INVALID;
6127     }
6128 }
6129 
6130 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6131     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6132     if (!conn) return HCI_ROLE_INVALID;
6133     return (hci_role_t) conn->role;
6134 }
6135 
6136 
6137 #ifdef ENABLE_CLASSIC
6138 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6139     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6140     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6141     conn->request_role = role;
6142     hci_run();
6143     return ERROR_CODE_SUCCESS;
6144 }
6145 #endif
6146 
6147 #ifdef ENABLE_BLE
6148 
6149 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){
6150     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6151     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6152 
6153     conn->le_phy_update_all_phys    = all_phys;
6154     conn->le_phy_update_tx_phys     = tx_phys;
6155     conn->le_phy_update_rx_phys     = rx_phys;
6156     conn->le_phy_update_phy_options = phy_options;
6157 
6158     hci_run();
6159 
6160     return 0;
6161 }
6162 
6163 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6164     // check if already in list
6165     btstack_linked_list_iterator_t it;
6166     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6167     while (btstack_linked_list_iterator_has_next(&it)) {
6168         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6169         if (entry->address_type != address_type) {
6170             continue;
6171         }
6172         if (memcmp(entry->address, address, 6) != 0) {
6173             continue;
6174         }
6175 		// disallow if already scheduled to add
6176 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6177 			return ERROR_CODE_COMMAND_DISALLOWED;
6178 		}
6179 		// still on controller, but scheduled to remove -> re-add
6180 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6181 		return ERROR_CODE_SUCCESS;
6182     }
6183     // alloc and add to list
6184     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6185     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6186     entry->address_type = address_type;
6187     (void)memcpy(entry->address, address, 6);
6188     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6189     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6190     return ERROR_CODE_SUCCESS;
6191 }
6192 
6193 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6194     btstack_linked_list_iterator_t it;
6195     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6196     while (btstack_linked_list_iterator_has_next(&it)){
6197         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6198         if (entry->address_type != address_type) {
6199             continue;
6200         }
6201         if (memcmp(entry->address, address, 6) != 0) {
6202             continue;
6203         }
6204         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6205             // remove from controller if already present
6206             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6207         }  else {
6208             // directly remove entry from whitelist
6209             btstack_linked_list_iterator_remove(&it);
6210             btstack_memory_whitelist_entry_free(entry);
6211         }
6212         return ERROR_CODE_SUCCESS;
6213     }
6214     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6215 }
6216 
6217 static void hci_whitelist_clear(void){
6218     btstack_linked_list_iterator_t it;
6219     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6220     while (btstack_linked_list_iterator_has_next(&it)){
6221         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6222         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6223             // remove from controller if already present
6224             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6225             continue;
6226         }
6227         // directly remove entry from whitelist
6228         btstack_linked_list_iterator_remove(&it);
6229         btstack_memory_whitelist_entry_free(entry);
6230     }
6231 }
6232 
6233 /**
6234  * @brief Clear Whitelist
6235  * @returns 0 if ok
6236  */
6237 uint8_t gap_whitelist_clear(void){
6238     hci_whitelist_clear();
6239     hci_run();
6240     return ERROR_CODE_SUCCESS;
6241 }
6242 
6243 /**
6244  * @brief Add Device to Whitelist
6245  * @param address_typ
6246  * @param address
6247  * @returns 0 if ok
6248  */
6249 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6250     uint8_t status = hci_whitelist_add(address_type, address);
6251     if (status){
6252         return status;
6253     }
6254     hci_run();
6255     return ERROR_CODE_SUCCESS;
6256 }
6257 
6258 /**
6259  * @brief Remove Device from Whitelist
6260  * @param address_typ
6261  * @param address
6262  * @returns 0 if ok
6263  */
6264 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6265     uint8_t status = hci_whitelist_remove(address_type, address);
6266     if (status){
6267         return status;
6268     }
6269     hci_run();
6270     return ERROR_CODE_SUCCESS;
6271 }
6272 
6273 #ifdef ENABLE_LE_CENTRAL
6274 /**
6275  *  @brief Connect with Whitelist
6276  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6277  *  @returns - if ok
6278  */
6279 uint8_t gap_connect_with_whitelist(void){
6280     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6281         return ERROR_CODE_COMMAND_DISALLOWED;
6282     }
6283     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6284     hci_run();
6285     return ERROR_CODE_SUCCESS;
6286 }
6287 
6288 /**
6289  * @brief Auto Connection Establishment - Start Connecting to device
6290  * @param address_typ
6291  * @param address
6292  * @returns 0 if ok
6293  */
6294 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6295     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6296         return ERROR_CODE_COMMAND_DISALLOWED;
6297     }
6298 
6299     uint8_t status = hci_whitelist_add(address_type, address);
6300     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6301         return status;
6302     }
6303 
6304     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6305 
6306     hci_run();
6307     return ERROR_CODE_SUCCESS;
6308 }
6309 
6310 /**
6311  * @brief Auto Connection Establishment - Stop Connecting to device
6312  * @param address_typ
6313  * @param address
6314  * @returns 0 if ok
6315  */
6316 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6317     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6318         return ERROR_CODE_COMMAND_DISALLOWED;
6319     }
6320 
6321     hci_whitelist_remove(address_type, address);
6322     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6323         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6324     }
6325     hci_run();
6326     return 0;
6327 }
6328 
6329 /**
6330  * @brief Auto Connection Establishment - Stop everything
6331  * @note  Convenience function to stop all active auto connection attempts
6332  */
6333 uint8_t gap_auto_connection_stop_all(void){
6334     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6335         return ERROR_CODE_COMMAND_DISALLOWED;
6336     }
6337     hci_whitelist_clear();
6338     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6339     hci_run();
6340     return ERROR_CODE_SUCCESS;
6341 }
6342 
6343 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6344     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6345     if (!conn) return 0;
6346     return conn->le_connection_interval;
6347 }
6348 #endif
6349 #endif
6350 
6351 #ifdef ENABLE_CLASSIC
6352 /**
6353  * @brief Set Extended Inquiry Response data
6354  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6355  * @note has to be done before stack starts up
6356  */
6357 void gap_set_extended_inquiry_response(const uint8_t * data){
6358     hci_stack->eir_data = data;
6359     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6360     hci_run();
6361 }
6362 
6363 /**
6364  * @brief Start GAP Classic Inquiry
6365  * @param duration in 1.28s units
6366  * @return 0 if ok
6367  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6368  */
6369 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6370     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6371     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6372     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6373         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6374     }
6375     hci_stack->inquiry_state = duration_in_1280ms_units;
6376     hci_run();
6377     return 0;
6378 }
6379 
6380 /**
6381  * @brief Stop GAP Classic Inquiry
6382  * @returns 0 if ok
6383  */
6384 int gap_inquiry_stop(void){
6385     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6386         // emit inquiry complete event, before it even started
6387         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6388         hci_emit_event(event, sizeof(event), 1);
6389         return 0;
6390     }
6391     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6392     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6393     hci_run();
6394     return 0;
6395 }
6396 
6397 void gap_inquiry_set_lap(uint32_t lap){
6398     hci_stack->inquiry_lap = lap;
6399 }
6400 
6401 
6402 /**
6403  * @brief Remote Name Request
6404  * @param addr
6405  * @param page_scan_repetition_mode
6406  * @param clock_offset only used when bit 15 is set
6407  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6408  */
6409 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6410     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6411     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6412     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6413     hci_stack->remote_name_clock_offset = clock_offset;
6414     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6415     hci_run();
6416     return 0;
6417 }
6418 
6419 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6420     hci_stack->gap_pairing_state = state;
6421     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6422     hci_run();
6423     return 0;
6424 }
6425 
6426 /**
6427  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6428  * @param addr
6429  * @param pin_data
6430  * @param pin_len
6431  * @return 0 if ok
6432  */
6433 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6434     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6435     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6436     hci_stack->gap_pairing_pin_len = pin_len;
6437     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6438 }
6439 
6440 /**
6441  * @brief Legacy Pairing Pin Code Response
6442  * @param addr
6443  * @param pin
6444  * @return 0 if ok
6445  */
6446 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6447     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6448 }
6449 
6450 /**
6451  * @brief Abort Legacy Pairing
6452  * @param addr
6453  * @param pin
6454  * @return 0 if ok
6455  */
6456 int gap_pin_code_negative(bd_addr_t addr){
6457     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6458     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6459 }
6460 
6461 /**
6462  * @brief SSP Passkey Response
6463  * @param addr
6464  * @param passkey
6465  * @return 0 if ok
6466  */
6467 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6468     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6469     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6470     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6471 }
6472 
6473 /**
6474  * @brief Abort SSP Passkey Entry/Pairing
6475  * @param addr
6476  * @param pin
6477  * @return 0 if ok
6478  */
6479 int gap_ssp_passkey_negative(const bd_addr_t addr){
6480     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6481     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6482 }
6483 
6484 /**
6485  * @brief Accept SSP Numeric Comparison
6486  * @param addr
6487  * @param passkey
6488  * @return 0 if ok
6489  */
6490 int gap_ssp_confirmation_response(const bd_addr_t addr){
6491     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6492     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6493 }
6494 
6495 /**
6496  * @brief Abort SSP Numeric Comparison/Pairing
6497  * @param addr
6498  * @param pin
6499  * @return 0 if ok
6500  */
6501 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6502     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6503     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6504 }
6505 
6506 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6507 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6508     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6509     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6510     connectionSetAuthenticationFlags(conn, flag);
6511     hci_run();
6512     return ERROR_CODE_SUCCESS;
6513 }
6514 #endif
6515 
6516 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6517 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6518     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6519 }
6520 
6521 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6522     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6523 }
6524 #endif
6525 
6526 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6527 /**
6528  * @brief Report Remote OOB Data
6529  * @param bd_addr
6530  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6531  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6532  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6533  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6534  */
6535 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){
6536     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6537     if (connection == NULL) {
6538         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6539     }
6540     connection->classic_oob_c_192 = c_192;
6541     connection->classic_oob_r_192 = r_192;
6542 
6543     // ignore P-256 if not supported by us
6544     if (hci_stack->secure_connections_active){
6545         connection->classic_oob_c_256 = c_256;
6546         connection->classic_oob_r_256 = r_256;
6547     }
6548 
6549     return ERROR_CODE_SUCCESS;
6550 }
6551 /**
6552  * @brief Generate new OOB data
6553  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6554  */
6555 void gap_ssp_generate_oob_data(void){
6556     hci_stack->classic_read_local_oob_data = true;
6557     hci_run();
6558 }
6559 
6560 #endif
6561 
6562 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6563 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6564     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6565     if (connection == NULL) {
6566         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6567     }
6568 
6569     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6570     connection->link_key_type = type;
6571 
6572     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6573 }
6574 
6575 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6576 /**
6577  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6578  * @param inquiry_mode see bluetooth_defines.h
6579  */
6580 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6581     hci_stack->inquiry_mode = inquiry_mode;
6582 }
6583 
6584 /**
6585  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6586  */
6587 void hci_set_sco_voice_setting(uint16_t voice_setting){
6588     hci_stack->sco_voice_setting = voice_setting;
6589 }
6590 
6591 /**
6592  * @brief Get SCO Voice Setting
6593  * @return current voice setting
6594  */
6595 uint16_t hci_get_sco_voice_setting(void){
6596     return hci_stack->sco_voice_setting;
6597 }
6598 
6599 static int hci_have_usb_transport(void){
6600     if (!hci_stack->hci_transport) return 0;
6601     const char * transport_name = hci_stack->hci_transport->name;
6602     if (!transport_name) return 0;
6603     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6604 }
6605 
6606 /** @brief Get SCO packet length for current SCO Voice setting
6607  *  @note  Using SCO packets of the exact length is required for USB transfer
6608  *  @return Length of SCO packets in bytes (not audio frames)
6609  */
6610 uint16_t hci_get_sco_packet_length(void){
6611     uint16_t sco_packet_length = 0;
6612 
6613 #ifdef ENABLE_SCO_OVER_HCI
6614     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6615     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6616 
6617     if (hci_have_usb_transport()){
6618         // see Core Spec for H2 USB Transfer.
6619         // 3 byte SCO header + 24 bytes per connection
6620         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6621         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6622     } else {
6623         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6624         sco_packet_length = 3 + 60 * multiplier;
6625         // assert that it still fits inside an SCO buffer
6626         if (sco_packet_length > hci_stack->sco_data_packet_length){
6627             sco_packet_length = 3 + 60;
6628         }
6629     }
6630 #endif
6631 
6632 #ifdef HAVE_SCO_TRANSPORT
6633     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6634     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6635     sco_packet_length = 3 + 60 * multiplier;
6636 #endif
6637     return sco_packet_length;
6638 }
6639 
6640 /**
6641 * @brief Sets the master/slave policy
6642 * @param policy (0: attempt to become master, 1: let connecting device decide)
6643 */
6644 void hci_set_master_slave_policy(uint8_t policy){
6645     hci_stack->master_slave_policy = policy;
6646 }
6647 
6648 #endif
6649 
6650 HCI_STATE hci_get_state(void){
6651     return hci_stack->state;
6652 }
6653 
6654 #ifdef ENABLE_CLASSIC
6655 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6656     hci_stack->gap_classic_accept_callback = accept_callback;
6657 }
6658 #endif
6659 
6660 /**
6661  * @brief Set callback for Bluetooth Hardware Error
6662  */
6663 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6664     hci_stack->hardware_error_callback = fn;
6665 }
6666 
6667 void hci_disconnect_all(void){
6668     btstack_linked_list_iterator_t it;
6669     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6670     while (btstack_linked_list_iterator_has_next(&it)){
6671         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6672         if (con->state == SENT_DISCONNECT) continue;
6673         con->state = SEND_DISCONNECT;
6674     }
6675     hci_run();
6676 }
6677 
6678 uint16_t hci_get_manufacturer(void){
6679     return hci_stack->manufacturer;
6680 }
6681 
6682 #ifdef ENABLE_BLE
6683 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6684     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6685     if (!hci_con) return NULL;
6686     return &hci_con->sm_connection;
6687 }
6688 
6689 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6690 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6691 #endif
6692 
6693 int gap_encryption_key_size(hci_con_handle_t con_handle){
6694     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6695     if (hci_connection == NULL) return 0;
6696     if (hci_is_le_connection(hci_connection)){
6697 #ifdef ENABLE_BLE
6698         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6699         if (sm_conn->sm_connection_encrypted) {
6700             return sm_conn->sm_actual_encryption_key_size;
6701         }
6702 #endif
6703     } else {
6704 #ifdef ENABLE_CLASSIC
6705         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6706             return hci_connection->encryption_key_size;
6707         }
6708 #endif
6709     }
6710     return 0;
6711 }
6712 
6713 int gap_authenticated(hci_con_handle_t con_handle){
6714     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6715     if (hci_connection == NULL) return 0;
6716 
6717     switch (hci_connection->address_type){
6718 #ifdef ENABLE_BLE
6719         case BD_ADDR_TYPE_LE_PUBLIC:
6720         case BD_ADDR_TYPE_LE_RANDOM:
6721             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6722             return hci_connection->sm_connection.sm_connection_authenticated;
6723 #endif
6724 #ifdef ENABLE_CLASSIC
6725         case BD_ADDR_TYPE_SCO:
6726         case BD_ADDR_TYPE_ACL:
6727             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6728 #endif
6729         default:
6730             return 0;
6731     }
6732 }
6733 
6734 int gap_secure_connection(hci_con_handle_t con_handle){
6735     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6736     if (hci_connection == NULL) return 0;
6737 
6738     switch (hci_connection->address_type){
6739 #ifdef ENABLE_BLE
6740         case BD_ADDR_TYPE_LE_PUBLIC:
6741         case BD_ADDR_TYPE_LE_RANDOM:
6742             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6743             return hci_connection->sm_connection.sm_connection_sc;
6744 #endif
6745 #ifdef ENABLE_CLASSIC
6746         case BD_ADDR_TYPE_SCO:
6747         case BD_ADDR_TYPE_ACL:
6748             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6749 #endif
6750         default:
6751             return 0;
6752     }
6753 }
6754 
6755 bool gap_bonded(hci_con_handle_t con_handle){
6756 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6757 	if (hci_connection == NULL) return 0;
6758 
6759 #ifdef ENABLE_CLASSIC
6760 	link_key_t link_key;
6761 	link_key_type_t link_key_type;
6762 #endif
6763 	switch (hci_connection->address_type){
6764 #ifdef ENABLE_BLE
6765 		case BD_ADDR_TYPE_LE_PUBLIC:
6766 		case BD_ADDR_TYPE_LE_RANDOM:
6767 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6768 #endif
6769 #ifdef ENABLE_CLASSIC
6770 		case BD_ADDR_TYPE_SCO:
6771 		case BD_ADDR_TYPE_ACL:
6772 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6773 #endif
6774 		default:
6775 			return false;
6776 	}
6777 }
6778 
6779 #ifdef ENABLE_BLE
6780 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6781     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6782     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6783     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6784     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6785     return sm_conn->sm_connection_authorization_state;
6786 }
6787 #endif
6788 
6789 #ifdef ENABLE_CLASSIC
6790 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){
6791     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6792     if (!conn) return GAP_CONNECTION_INVALID;
6793     conn->sniff_min_interval = sniff_min_interval;
6794     conn->sniff_max_interval = sniff_max_interval;
6795     conn->sniff_attempt = sniff_attempt;
6796     conn->sniff_timeout = sniff_timeout;
6797     hci_run();
6798     return 0;
6799 }
6800 
6801 /**
6802  * @brief Exit Sniff mode
6803  * @param con_handle
6804  @ @return 0 if ok
6805  */
6806 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6807     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6808     if (!conn) return GAP_CONNECTION_INVALID;
6809     conn->sniff_min_interval = 0xffff;
6810     hci_run();
6811     return 0;
6812 }
6813 
6814 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){
6815     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6816     if (!conn) return GAP_CONNECTION_INVALID;
6817     conn->sniff_subrating_max_latency = max_latency;
6818     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6819     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6820     hci_run();
6821     return ERROR_CODE_SUCCESS;
6822 }
6823 
6824 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){
6825     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6826     if (!conn) return GAP_CONNECTION_INVALID;
6827     conn->qos_service_type = service_type;
6828     conn->qos_token_rate = token_rate;
6829     conn->qos_peak_bandwidth = peak_bandwidth;
6830     conn->qos_latency = latency;
6831     conn->qos_delay_variation = delay_variation;
6832     hci_run();
6833     return ERROR_CODE_SUCCESS;
6834 }
6835 
6836 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6837     hci_stack->new_page_scan_interval = page_scan_interval;
6838     hci_stack->new_page_scan_window = page_scan_window;
6839     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6840     hci_run();
6841 }
6842 
6843 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6844     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6845     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6846     hci_run();
6847 }
6848 
6849 void gap_set_page_timeout(uint16_t page_timeout){
6850     hci_stack->page_timeout = page_timeout;
6851     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_TIMEOUT;
6852     hci_run();
6853 }
6854 
6855 #endif
6856 
6857 void hci_halting_defer(void){
6858     if (hci_stack->state != HCI_STATE_HALTING) return;
6859     switch (hci_stack->substate){
6860         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6861         case HCI_HALTING_CLOSE:
6862             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6863             break;
6864         default:
6865             break;
6866     }
6867 }
6868 
6869 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6870 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6871     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6872     if (le_device_db_index >= le_device_db_max_count()) return;
6873     uint8_t offset = le_device_db_index >> 3;
6874     uint8_t mask = 1 << (le_device_db_index & 7);
6875     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6876     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6877     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6878         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6879     }
6880 }
6881 
6882 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6883 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6884 	if (le_device_db_index >= le_device_db_max_count()) return;
6885 	uint8_t offset = le_device_db_index >> 3;
6886 	uint8_t mask = 1 << (le_device_db_index & 7);
6887 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6888 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6889 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6890 	}
6891 }
6892 
6893 uint8_t gap_load_resolving_list_from_le_device_db(void){
6894 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6895 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6896 	}
6897 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6898 		// restart le resolving list update
6899 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6900 	}
6901 	return ERROR_CODE_SUCCESS;
6902 }
6903 #endif
6904 
6905 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6906 void hci_setup_test_connections_fuzz(void){
6907     hci_connection_t * conn;
6908 
6909     // default address: 66:55:44:33:00:01
6910     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6911 
6912     // setup Controller info
6913     hci_stack->num_cmd_packets = 255;
6914     hci_stack->acl_packets_total_num = 255;
6915 
6916     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6917     addr[5] = 0x01;
6918     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6919     conn->con_handle = addr[5];
6920     conn->role  = HCI_ROLE_SLAVE;
6921     conn->state = RECEIVED_CONNECTION_REQUEST;
6922     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6923 
6924     // setup incoming Classic SCO connection with con handle 0x0002
6925     addr[5] = 0x02;
6926     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6927     conn->con_handle = addr[5];
6928     conn->role  = HCI_ROLE_SLAVE;
6929     conn->state = RECEIVED_CONNECTION_REQUEST;
6930     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6931 
6932     // setup ready Classic ACL connection with con handle 0x0003
6933     addr[5] = 0x03;
6934     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
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 Classic SCO connection with con handle 0x0004
6941     addr[5] = 0x04;
6942     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
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 
6948     // setup ready LE ACL connection with con handle 0x005 and public address
6949     addr[5] = 0x05;
6950     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6951     conn->con_handle = addr[5];
6952     conn->role  = HCI_ROLE_SLAVE;
6953     conn->state = OPEN;
6954     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6955     conn->sm_connection.sm_connection_encrypted = 1;
6956 }
6957 
6958 void hci_free_connections_fuzz(void){
6959     btstack_linked_list_iterator_t it;
6960     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6961     while (btstack_linked_list_iterator_has_next(&it)){
6962         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6963         btstack_linked_list_iterator_remove(&it);
6964         btstack_memory_hci_connection_free(con);
6965     }
6966 }
6967 void hci_simulate_working_fuzz(void){
6968     hci_init_done();
6969     hci_stack->num_cmd_packets = 255;
6970 }
6971 #endif
6972