xref: /btstack/src/hci.c (revision f5228c62dfa305f00bfdabbb48dafdc0b8919667)
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 HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->role = HCI_ROLE_INVALID;
199     conn->address_type = addr_type;
200     conn->con_handle = 0xffff;
201     conn->authentication_flags = AUTH_FLAGS_NONE;
202     conn->bonding_flags = 0;
203     conn->requested_security_level = LEVEL_0;
204 #ifdef ENABLE_CLASSIC
205     conn->request_role = HCI_ROLE_INVALID;
206     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
207     btstack_run_loop_set_timer_context(&conn->timeout, conn);
208     hci_connection_timestamp(conn);
209 #endif
210     conn->acl_recombination_length = 0;
211     conn->acl_recombination_pos = 0;
212     conn->num_packets_sent = 0;
213 
214     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
215 #ifdef ENABLE_BLE
216     conn->le_phy_update_all_phys = 0xff;
217 #endif
218 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
219     conn->le_max_tx_octets = 27;
220 #endif
221     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
222     return conn;
223 }
224 
225 
226 /**
227  * get le connection parameter range
228 *
229  * @return le connection parameter range struct
230  */
231 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
232     *range = hci_stack->le_connection_parameter_range;
233 }
234 
235 /**
236  * set le connection parameter range
237  *
238  */
239 
240 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
241     hci_stack->le_connection_parameter_range = *range;
242 }
243 
244 /**
245  * @brief Test if connection parameters are inside in existing rage
246  * @param conn_interval_min (unit: 1.25ms)
247  * @param conn_interval_max (unit: 1.25ms)
248  * @param conn_latency
249  * @param supervision_timeout (unit: 10ms)
250  * @returns 1 if included
251  */
252 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){
253     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
254     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
255 
256     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
257     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
258 
259     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
260     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
261 
262     return 1;
263 }
264 
265 /**
266  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
267  * @note: default: 1
268  * @param max_peripheral_connections
269  */
270 #ifdef ENABLE_LE_PERIPHERAL
271 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
272     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
273 }
274 #endif
275 
276 /**
277  * get hci connections iterator
278  *
279  * @return hci connections iterator
280  */
281 
282 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
283     btstack_linked_list_iterator_init(it, &hci_stack->connections);
284 }
285 
286 /**
287  * get connection for a given handle
288  *
289  * @return connection OR NULL, if not found
290  */
291 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
292     btstack_linked_list_iterator_t it;
293     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
294     while (btstack_linked_list_iterator_has_next(&it)){
295         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
296         if ( item->con_handle == con_handle ) {
297             return item;
298         }
299     }
300     return NULL;
301 }
302 
303 /**
304  * get connection for given address
305  *
306  * @return connection OR NULL, if not found
307  */
308 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
309     btstack_linked_list_iterator_t it;
310     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
311     while (btstack_linked_list_iterator_has_next(&it)){
312         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
313         if (connection->address_type != addr_type)  continue;
314         if (memcmp(addr, connection->address, 6) != 0) continue;
315         return connection;
316     }
317     return NULL;
318 }
319 
320 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
321     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
322 }
323 
324 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
325     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
326 }
327 
328 #ifdef ENABLE_CLASSIC
329 
330 #ifdef ENABLE_SCO_OVER_HCI
331 static int hci_number_sco_connections(void){
332     int connections = 0;
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 != BD_ADDR_TYPE_SCO) continue;
338         connections++;
339     }
340     return connections;
341 }
342 #endif
343 
344 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
345     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
346 #ifdef HAVE_EMBEDDED_TICK
347     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
348         // connections might be timed out
349         hci_emit_l2cap_check_timeout(connection);
350     }
351 #else
352     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
353         // connections might be timed out
354         hci_emit_l2cap_check_timeout(connection);
355     }
356 #endif
357 }
358 
359 static void hci_connection_timestamp(hci_connection_t *connection){
360 #ifdef HAVE_EMBEDDED_TICK
361     connection->timestamp = btstack_run_loop_embedded_get_ticks();
362 #else
363     connection->timestamp = btstack_run_loop_get_time_ms();
364 #endif
365 }
366 
367 /**
368  * add authentication flags and reset timer
369  * @note: assumes classic connection
370  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
371  */
372 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
373     bd_addr_t addr;
374     reverse_bd_addr(bd_addr, addr);
375     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
376     if (conn) {
377         connectionSetAuthenticationFlags(conn, flags);
378         hci_connection_timestamp(conn);
379     }
380 }
381 
382 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
383     hci_connection_t * conn = hci_connection_for_handle(handle);
384     if (!conn) return 0;
385     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
386     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
387     return 0;
388 }
389 
390 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
391     if (!hci_stack->link_key_db) return;
392     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
393     hci_stack->link_key_db->delete_link_key(addr);
394 }
395 
396 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
397     if (!hci_stack->link_key_db) return;
398     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
399     hci_stack->link_key_db->put_link_key(addr, link_key, type);
400 }
401 
402 void gap_delete_all_link_keys(void){
403     bd_addr_t  addr;
404     link_key_t link_key;
405     link_key_type_t type;
406     btstack_link_key_iterator_t it;
407     int ok = gap_link_key_iterator_init(&it);
408     if (!ok) {
409         log_error("could not initialize iterator");
410         return;
411     }
412     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
413         gap_drop_link_key_for_bd_addr(addr);
414     }
415     gap_link_key_iterator_done(&it);
416 }
417 
418 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
419     if (!hci_stack->link_key_db) return 0;
420     if (!hci_stack->link_key_db->iterator_init) return 0;
421     return hci_stack->link_key_db->iterator_init(it);
422 }
423 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){
424     if (!hci_stack->link_key_db) return 0;
425     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
426 }
427 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
428     if (!hci_stack->link_key_db) return;
429     hci_stack->link_key_db->iterator_done(it);
430 }
431 #endif
432 
433 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
434     switch (address_type){
435         case BD_ADDR_TYPE_LE_PUBLIC:
436         case BD_ADDR_TYPE_LE_RANDOM:
437         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
438         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
439             return true;
440         default:
441             return false;
442     }
443 }
444 
445 static int hci_is_le_connection(hci_connection_t * connection){
446     return hci_is_le_connection_type(connection->address_type);
447 }
448 
449 /**
450  * count connections
451  */
452 static int nr_hci_connections(void){
453     int count = 0;
454     btstack_linked_item_t *it;
455     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
456         count++;
457     }
458     return count;
459 }
460 
461 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
462 
463     unsigned int num_packets_sent_classic = 0;
464     unsigned int num_packets_sent_le = 0;
465 
466     btstack_linked_item_t *it;
467     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
468         hci_connection_t * connection = (hci_connection_t *) it;
469         if (hci_is_le_connection(connection)){
470             num_packets_sent_le += connection->num_packets_sent;
471         }
472         if (connection->address_type == BD_ADDR_TYPE_ACL){
473             num_packets_sent_classic += connection->num_packets_sent;
474         }
475     }
476     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
477     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
478     int free_slots_le = 0;
479 
480     if (free_slots_classic < 0){
481         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);
482         return 0;
483     }
484 
485     if (hci_stack->le_acl_packets_total_num){
486         // if we have LE slots, they are used
487         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
488         if (free_slots_le < 0){
489             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);
490             return 0;
491         }
492     } else {
493         // otherwise, classic slots are used for LE, too
494         free_slots_classic -= num_packets_sent_le;
495         if (free_slots_classic < 0){
496             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);
497             return 0;
498         }
499     }
500 
501     switch (address_type){
502         case BD_ADDR_TYPE_UNKNOWN:
503             log_error("hci_number_free_acl_slots: unknown address type");
504             return 0;
505 
506         case BD_ADDR_TYPE_ACL:
507             return free_slots_classic;
508 
509         default:
510            if (hci_stack->le_acl_packets_total_num){
511                return free_slots_le;
512            }
513            return free_slots_classic;
514     }
515 }
516 
517 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
518     // get connection type
519     hci_connection_t * connection = hci_connection_for_handle(con_handle);
520     if (!connection){
521         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
522         return 0;
523     }
524     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
525 }
526 
527 #ifdef ENABLE_CLASSIC
528 static int hci_number_free_sco_slots(void){
529     unsigned int num_sco_packets_sent  = 0;
530     btstack_linked_item_t *it;
531     if (hci_stack->synchronous_flow_control_enabled){
532         // explicit flow control
533         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
534             hci_connection_t * connection = (hci_connection_t *) it;
535             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
536             num_sco_packets_sent += connection->num_packets_sent;
537         }
538         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
539             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
540             return 0;
541         }
542         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
543     } else {
544         // implicit flow control -- TODO
545         int num_ready = 0;
546         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
547             hci_connection_t * connection = (hci_connection_t *) it;
548             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
549             if (connection->sco_tx_ready == 0) continue;
550             num_ready++;
551         }
552         return num_ready;
553     }
554 }
555 #endif
556 
557 // only used to send HCI Host Number Completed Packets
558 static int hci_can_send_comand_packet_transport(void){
559     if (hci_stack->hci_packet_buffer_reserved) return 0;
560 
561     // check for async hci transport implementations
562     if (hci_stack->hci_transport->can_send_packet_now){
563         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
564             return 0;
565         }
566     }
567     return 1;
568 }
569 
570 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
571 int hci_can_send_command_packet_now(void){
572     if (hci_can_send_comand_packet_transport() == 0) return 0;
573     return hci_stack->num_cmd_packets > 0u;
574 }
575 
576 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
577     // check for async hci transport implementations
578     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
579     return hci_stack->hci_transport->can_send_packet_now(packet_type);
580 }
581 
582 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
583     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
584     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
585 }
586 
587 int hci_can_send_acl_le_packet_now(void){
588     if (hci_stack->hci_packet_buffer_reserved) return 0;
589     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
590 }
591 
592 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
593     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
594     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
595 }
596 
597 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
598     if (hci_stack->hci_packet_buffer_reserved) return 0;
599     return hci_can_send_prepared_acl_packet_now(con_handle);
600 }
601 
602 #ifdef ENABLE_CLASSIC
603 int hci_can_send_acl_classic_packet_now(void){
604     if (hci_stack->hci_packet_buffer_reserved) return 0;
605     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
606 }
607 
608 int hci_can_send_prepared_sco_packet_now(void){
609     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
610     if (hci_have_usb_transport()){
611         return hci_stack->sco_can_send_now;
612     } else {
613         return hci_number_free_sco_slots() > 0;
614     }
615 }
616 
617 int hci_can_send_sco_packet_now(void){
618     if (hci_stack->hci_packet_buffer_reserved) return 0;
619     return hci_can_send_prepared_sco_packet_now();
620 }
621 
622 void hci_request_sco_can_send_now_event(void){
623     hci_stack->sco_waiting_for_can_send_now = 1;
624     hci_notify_if_sco_can_send_now();
625 }
626 #endif
627 
628 // used for internal checks in l2cap.c
629 int hci_is_packet_buffer_reserved(void){
630     return hci_stack->hci_packet_buffer_reserved;
631 }
632 
633 // reserves outgoing packet buffer. @returns 1 if successful
634 int hci_reserve_packet_buffer(void){
635     if (hci_stack->hci_packet_buffer_reserved) {
636         log_error("hci_reserve_packet_buffer called but buffer already reserved");
637         return 0;
638     }
639     hci_stack->hci_packet_buffer_reserved = 1;
640     return 1;
641 }
642 
643 void hci_release_packet_buffer(void){
644     hci_stack->hci_packet_buffer_reserved = 0;
645 }
646 
647 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
648 static int hci_transport_synchronous(void){
649     return hci_stack->hci_transport->can_send_packet_now == NULL;
650 }
651 
652 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
653 
654     // 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);
655 
656     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
657     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
658     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
659         max_acl_data_packet_length = hci_stack->le_data_packets_length;
660     }
661 
662 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
663     if (hci_is_le_connection(connection)){
664         max_acl_data_packet_length = connection->le_max_tx_octets;
665     }
666 #endif
667 
668     log_debug("hci_send_acl_packet_fragments entered");
669 
670     int err;
671     // multiple packets could be send on a synchronous HCI transport
672     while (true){
673 
674         log_debug("hci_send_acl_packet_fragments loop entered");
675 
676         // get current data
677         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
678         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
679         int more_fragments = 0;
680 
681         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
682         if (current_acl_data_packet_length > max_acl_data_packet_length){
683             more_fragments = 1;
684             current_acl_data_packet_length = max_acl_data_packet_length;
685         }
686 
687         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
688         if (acl_header_pos > 0u){
689             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
690             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
691             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
692         }
693 
694         // update header len
695         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
696 
697         // count packet
698         connection->num_packets_sent++;
699         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
700 
701         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
702         if (more_fragments){
703             // update start of next fragment to send
704             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
705         } else {
706             // done
707             hci_stack->acl_fragmentation_pos = 0;
708             hci_stack->acl_fragmentation_total_size = 0;
709         }
710 
711         // send packet
712         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
713         const int size = current_acl_data_packet_length + 4;
714         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
715         hci_stack->acl_fragmentation_tx_active = 1;
716         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
717 
718         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
719 
720         // done yet?
721         if (!more_fragments) break;
722 
723         // can send more?
724         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
725     }
726 
727     log_debug("hci_send_acl_packet_fragments loop over");
728 
729     // release buffer now for synchronous transport
730     if (hci_transport_synchronous()){
731         hci_stack->acl_fragmentation_tx_active = 0;
732         hci_release_packet_buffer();
733         hci_emit_transport_packet_sent();
734     }
735 
736     return err;
737 }
738 
739 // pre: caller has reserved the packet buffer
740 int hci_send_acl_packet_buffer(int size){
741 
742     // log_info("hci_send_acl_packet_buffer size %u", size);
743 
744     if (!hci_stack->hci_packet_buffer_reserved) {
745         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
746         return 0;
747     }
748 
749     uint8_t * packet = hci_stack->hci_packet_buffer;
750     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
751 
752     // check for free places on Bluetooth module
753     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
754         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
755         hci_release_packet_buffer();
756         hci_emit_transport_packet_sent();
757         return BTSTACK_ACL_BUFFERS_FULL;
758     }
759 
760     hci_connection_t *connection = hci_connection_for_handle( con_handle);
761     if (!connection) {
762         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
763         hci_release_packet_buffer();
764         hci_emit_transport_packet_sent();
765         return 0;
766     }
767 
768 #ifdef ENABLE_CLASSIC
769     hci_connection_timestamp(connection);
770 #endif
771 
772     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
773 
774     // setup data
775     hci_stack->acl_fragmentation_total_size = size;
776     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
777 
778     return hci_send_acl_packet_fragments(connection);
779 }
780 
781 #ifdef ENABLE_CLASSIC
782 // pre: caller has reserved the packet buffer
783 int hci_send_sco_packet_buffer(int size){
784 
785     // log_info("hci_send_acl_packet_buffer size %u", size);
786 
787     if (!hci_stack->hci_packet_buffer_reserved) {
788         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
789         return 0;
790     }
791 
792     uint8_t * packet = hci_stack->hci_packet_buffer;
793 
794     // skip checks in loopback mode
795     if (!hci_stack->loopback_mode){
796         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
797 
798         // check for free places on Bluetooth module
799         if (!hci_can_send_prepared_sco_packet_now()) {
800             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
801             hci_release_packet_buffer();
802             hci_emit_transport_packet_sent();
803             return BTSTACK_ACL_BUFFERS_FULL;
804         }
805 
806         // track send packet in connection struct
807         hci_connection_t *connection = hci_connection_for_handle( con_handle);
808         if (!connection) {
809             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
810             hci_release_packet_buffer();
811             hci_emit_transport_packet_sent();
812             return 0;
813         }
814 
815         if (hci_have_usb_transport()){
816             // token used
817             hci_stack->sco_can_send_now = 0;
818         } else {
819             if (hci_stack->synchronous_flow_control_enabled){
820                 connection->num_packets_sent++;
821             } else {
822                 connection->sco_tx_ready--;
823             }
824         }
825     }
826 
827     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
828     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
829 
830     if (hci_transport_synchronous()){
831         hci_release_packet_buffer();
832         hci_emit_transport_packet_sent();
833     }
834 
835     return err;
836 }
837 #endif
838 
839 static void acl_handler(uint8_t *packet, uint16_t size){
840 
841     // get info
842     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
843     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
844     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
845     uint16_t acl_length         = READ_ACL_LENGTH(packet);
846 
847     // ignore non-registered handle
848     if (!conn){
849         log_error("acl_handler called with non-registered handle %u!" , con_handle);
850         return;
851     }
852 
853     // assert packet is complete
854     if ((acl_length + 4u) != size){
855         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
856         return;
857     }
858 
859 #ifdef ENABLE_CLASSIC
860     // update idle timestamp
861     hci_connection_timestamp(conn);
862 #endif
863 
864 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
865     hci_stack->host_completed_packets = 1;
866     conn->num_packets_completed++;
867 #endif
868 
869     // handle different packet types
870     switch (acl_flags & 0x03u) {
871 
872         case 0x01: // continuation fragment
873 
874             // sanity checks
875             if (conn->acl_recombination_pos == 0u) {
876                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
877                 return;
878             }
879             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
880                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
881                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
882                 conn->acl_recombination_pos = 0;
883                 return;
884             }
885 
886             // append fragment payload (header already stored)
887             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
888                          &packet[4], acl_length);
889             conn->acl_recombination_pos += acl_length;
890 
891             // forward complete L2CAP packet if complete.
892             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
893                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
894                 // reset recombination buffer
895                 conn->acl_recombination_length = 0;
896                 conn->acl_recombination_pos = 0;
897             }
898             break;
899 
900         case 0x02: { // first fragment
901 
902             // sanity check
903             if (conn->acl_recombination_pos) {
904                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
905                 conn->acl_recombination_pos = 0;
906             }
907 
908             // peek into L2CAP packet!
909             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
910 
911             // compare fragment size to L2CAP packet size
912             if (acl_length >= (l2cap_length + 4u)){
913                 // forward fragment as L2CAP packet
914                 hci_emit_acl_packet(packet, acl_length + 4u);
915             } else {
916 
917                 if (acl_length > HCI_ACL_BUFFER_SIZE){
918                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
919                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
920                     return;
921                 }
922 
923                 // store first fragment and tweak acl length for complete package
924                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
925                              packet, acl_length + 4u);
926                 conn->acl_recombination_pos    = acl_length + 4u;
927                 conn->acl_recombination_length = l2cap_length;
928                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
929             }
930             break;
931 
932         }
933         default:
934             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
935             return;
936     }
937 
938     // execute main loop
939     hci_run();
940 }
941 
942 static void hci_shutdown_connection(hci_connection_t *conn){
943     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
944 
945 #ifdef ENABLE_CLASSIC
946 #ifdef ENABLE_SCO_OVER_HCI
947     int addr_type = conn->address_type;
948 #endif
949 #endif
950 
951     btstack_run_loop_remove_timer(&conn->timeout);
952 
953     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
954     btstack_memory_hci_connection_free( conn );
955 
956     // now it's gone
957     hci_emit_nr_connections_changed();
958 
959 #ifdef ENABLE_CLASSIC
960 #ifdef ENABLE_SCO_OVER_HCI
961     // update SCO
962     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
963         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
964     }
965 #endif
966 #endif
967 }
968 
969 #ifdef ENABLE_CLASSIC
970 
971 static const uint16_t packet_type_sizes[] = {
972     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
973     HCI_ACL_DH1_SIZE, 0, 0, 0,
974     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
975     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
976 };
977 static const uint8_t  packet_type_feature_requirement_bit[] = {
978      0, // 3 slot packets
979      1, // 5 slot packets
980     25, // EDR 2 mpbs
981     26, // EDR 3 mbps
982     39, // 3 slot EDR packts
983     40, // 5 slot EDR packet
984 };
985 static const uint16_t packet_type_feature_packet_mask[] = {
986     0x0f00, // 3 slot packets
987     0xf000, // 5 slot packets
988     0x1102, // EDR 2 mpbs
989     0x2204, // EDR 3 mbps
990     0x0300, // 3 slot EDR packts
991     0x3000, // 5 slot EDR packet
992 };
993 
994 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
995     // enable packet types based on size
996     uint16_t packet_types = 0;
997     unsigned int i;
998     for (i=0;i<16;i++){
999         if (packet_type_sizes[i] == 0) continue;
1000         if (packet_type_sizes[i] <= buffer_size){
1001             packet_types |= 1 << i;
1002         }
1003     }
1004     // disable packet types due to missing local supported features
1005     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1006         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1007         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1008         if (feature_set) continue;
1009         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1010         packet_types &= ~packet_type_feature_packet_mask[i];
1011     }
1012     // flip bits for "may not be used"
1013     packet_types ^= 0x3306;
1014     return packet_types;
1015 }
1016 
1017 uint16_t hci_usable_acl_packet_types(void){
1018     return hci_stack->packet_types;
1019 }
1020 #endif
1021 
1022 uint8_t* hci_get_outgoing_packet_buffer(void){
1023     // hci packet buffer is >= acl data packet length
1024     return hci_stack->hci_packet_buffer;
1025 }
1026 
1027 uint16_t hci_max_acl_data_packet_length(void){
1028     return hci_stack->acl_data_packet_length;
1029 }
1030 
1031 #ifdef ENABLE_CLASSIC
1032 int hci_extended_sco_link_supported(void){
1033     // No. 31, byte 3, bit 7
1034     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1035 }
1036 #endif
1037 
1038 int hci_non_flushable_packet_boundary_flag_supported(void){
1039     // No. 54, byte 6, bit 6
1040     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1041 }
1042 
1043 static int gap_ssp_supported(void){
1044     // No. 51, byte 6, bit 3
1045     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1046 }
1047 
1048 static int hci_classic_supported(void){
1049 #ifdef ENABLE_CLASSIC
1050     // No. 37, byte 4, bit 5, = No BR/EDR Support
1051     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1052 #else
1053     return 0;
1054 #endif
1055 }
1056 
1057 static int hci_le_supported(void){
1058 #ifdef ENABLE_BLE
1059     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1060     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1061 #else
1062     return 0;
1063 #endif
1064 }
1065 
1066 #ifdef ENABLE_BLE
1067 
1068 /**
1069  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1070  */
1071 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1072     *addr_type = hci_stack->le_own_addr_type;
1073     if (hci_stack->le_own_addr_type){
1074         (void)memcpy(addr, hci_stack->le_random_address, 6);
1075     } else {
1076         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1077     }
1078 }
1079 
1080 #ifdef ENABLE_LE_CENTRAL
1081 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1082 
1083     int offset = 3;
1084     int num_reports = packet[offset];
1085     offset += 1;
1086 
1087     int i;
1088     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1089     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1090     for (i=0; (i<num_reports) && (offset < size);i++){
1091         // sanity checks on data_length:
1092         uint8_t data_length = packet[offset + 8];
1093         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1094         if ((offset + 9u + data_length + 1u) > size)    return;
1095         // setup event
1096         uint8_t event_size = 10u + data_length;
1097         int pos = 0;
1098         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1099         event[pos++] = event_size;
1100         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1101         offset += 8;
1102         pos += 8;
1103         event[pos++] = packet[offset + 1 + data_length]; // rssi
1104         event[pos++] = data_length;
1105         offset++;
1106         (void)memcpy(&event[pos], &packet[offset], data_length);
1107         pos +=    data_length;
1108         offset += data_length + 1u; // rssi
1109         hci_emit_event(event, pos, 1);
1110     }
1111 }
1112 #endif
1113 #endif
1114 
1115 #ifdef ENABLE_BLE
1116 #ifdef ENABLE_LE_PERIPHERAL
1117 static void hci_update_advertisements_enabled_for_current_roles(void){
1118     if (hci_stack->le_advertisements_enabled){
1119         // get number of active le slave connections
1120         int num_slave_connections = 0;
1121         btstack_linked_list_iterator_t it;
1122         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1123         while (btstack_linked_list_iterator_has_next(&it)){
1124             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1125             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1126             if (con->state != OPEN) continue;
1127             if (con->role  != HCI_ROLE_SLAVE) continue;
1128             if (!hci_is_le_connection(con)) continue;
1129             num_slave_connections++;
1130         }
1131         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1132         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1133     } else {
1134         hci_stack->le_advertisements_enabled_for_current_roles = false;
1135     }
1136 }
1137 #endif
1138 #endif
1139 
1140 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1141 
1142 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1143     if (!hci_stack->config) return 0;
1144     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1145     // Limit baud rate for Broadcom chipsets to 3 mbps
1146     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1147         baud_rate = 3000000;
1148     }
1149     return baud_rate;
1150 }
1151 
1152 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1153     UNUSED(ds);
1154 
1155     switch (hci_stack->substate){
1156         case HCI_INIT_W4_SEND_RESET:
1157             log_info("Resend HCI Reset");
1158             hci_stack->substate = HCI_INIT_SEND_RESET;
1159             hci_stack->num_cmd_packets = 1;
1160             hci_run();
1161             break;
1162         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1163             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1164             if (hci_stack->hci_transport->reset_link){
1165                 hci_stack->hci_transport->reset_link();
1166             }
1167 
1168             /* fall through */
1169 
1170         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1171             log_info("Resend HCI Reset - CSR Warm Boot");
1172             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1173             hci_stack->num_cmd_packets = 1;
1174             hci_run();
1175             break;
1176         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1177             if (hci_stack->hci_transport->set_baudrate){
1178                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1179                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1180                 hci_stack->hci_transport->set_baudrate(baud_rate);
1181             }
1182             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1183             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1184                 if (hci_stack->hci_transport->reset_link){
1185                     log_info("Link Reset");
1186                     hci_stack->hci_transport->reset_link();
1187                 }
1188                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1189                 hci_run();
1190             }
1191             break;
1192         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1193             // otherwise continue
1194             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1195             hci_send_cmd(&hci_read_local_supported_commands);
1196             break;
1197         default:
1198             break;
1199     }
1200 }
1201 #endif
1202 
1203 static void hci_initializing_next_state(void){
1204     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1205 }
1206 
1207 // assumption: hci_can_send_command_packet_now() == true
1208 static void hci_initializing_run(void){
1209     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1210     switch (hci_stack->substate){
1211         case HCI_INIT_SEND_RESET:
1212             hci_state_reset();
1213 
1214 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1215             // prepare reset if command complete not received in 100ms
1216             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1217             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1218             btstack_run_loop_add_timer(&hci_stack->timeout);
1219 #endif
1220             // send command
1221             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1222             hci_send_cmd(&hci_reset);
1223             break;
1224         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1225             hci_send_cmd(&hci_read_local_version_information);
1226             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1227             break;
1228         case HCI_INIT_SEND_READ_LOCAL_NAME:
1229             hci_send_cmd(&hci_read_local_name);
1230             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1231             break;
1232 
1233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1234         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1235             hci_state_reset();
1236             // prepare reset if command complete not received in 100ms
1237             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1238             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1239             btstack_run_loop_add_timer(&hci_stack->timeout);
1240             // send command
1241             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1242             hci_send_cmd(&hci_reset);
1243             break;
1244         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1245             hci_state_reset();
1246             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1247             hci_send_cmd(&hci_reset);
1248             break;
1249         case HCI_INIT_SEND_BAUD_CHANGE: {
1250             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1251             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1252             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1253             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1254             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1255             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1256             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1257             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1258                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1259                 btstack_run_loop_add_timer(&hci_stack->timeout);
1260             }
1261             break;
1262         }
1263         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1264             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1265             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1266             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1267             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1268             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1269             break;
1270         }
1271         case HCI_INIT_CUSTOM_INIT:
1272             // Custom initialization
1273             if (hci_stack->chipset && hci_stack->chipset->next_command){
1274                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1275                 int send_cmd = 0;
1276                 switch (hci_stack->chipset_result){
1277                     case BTSTACK_CHIPSET_VALID_COMMAND:
1278                         send_cmd = 1;
1279                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1280                         break;
1281                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1282                         send_cmd = 1;
1283                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1284                         log_info("CSR Warm Boot");
1285                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1286                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1287                         btstack_run_loop_add_timer(&hci_stack->timeout);
1288                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1289                             && hci_stack->config
1290                             && hci_stack->chipset
1291                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1292                             && hci_stack->hci_transport->set_baudrate
1293                             && hci_transport_uart_get_main_baud_rate()){
1294                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1295                         } else {
1296                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1297                         }
1298                         break;
1299                     default:
1300                         break;
1301                 }
1302 
1303                 if (send_cmd){
1304                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1305                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1306                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1307                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1308                     break;
1309                 }
1310                 log_info("Init script done");
1311 
1312                 // Init script download on Broadcom chipsets causes:
1313                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1314                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1315                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1316 
1317                     // - baud rate to reset, restore UART baud rate if needed
1318                     int need_baud_change = hci_stack->config
1319                         && hci_stack->chipset
1320                         && hci_stack->chipset->set_baudrate_command
1321                         && hci_stack->hci_transport->set_baudrate
1322                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1323                     if (need_baud_change) {
1324                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1325                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1326                         hci_stack->hci_transport->set_baudrate(baud_rate);
1327                     }
1328 
1329                     uint16_t bcm_delay_ms = 300;
1330                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1331                     //   -> Work around: wait here.
1332                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1333                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1334                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1335                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1336                     btstack_run_loop_add_timer(&hci_stack->timeout);
1337                     break;
1338                 }
1339             }
1340             // otherwise continue
1341             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1342             hci_send_cmd(&hci_read_local_supported_commands);
1343             break;
1344         case HCI_INIT_SET_BD_ADDR:
1345             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1346             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1347             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1348             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1349             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1350             break;
1351 #endif
1352 
1353         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1354             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1355             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1356             hci_send_cmd(&hci_read_local_supported_commands);
1357             break;
1358         case HCI_INIT_READ_BD_ADDR:
1359             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1360             hci_send_cmd(&hci_read_bd_addr);
1361             break;
1362         case HCI_INIT_READ_BUFFER_SIZE:
1363             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1364             hci_send_cmd(&hci_read_buffer_size);
1365             break;
1366         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1367             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1368             hci_send_cmd(&hci_read_local_supported_features);
1369             break;
1370 
1371 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1372         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1373             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1374             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1375             break;
1376         case HCI_INIT_HOST_BUFFER_SIZE:
1377             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1378             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1379                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1380             break;
1381 #endif
1382 
1383         case HCI_INIT_SET_EVENT_MASK:
1384             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1385             if (hci_le_supported()){
1386                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1387             } else {
1388                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1389                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1390             }
1391             break;
1392 
1393 #ifdef ENABLE_CLASSIC
1394         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1395             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1396             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1397             break;
1398         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1399             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1400             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1401             break;
1402         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1403             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1404             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1405             break;
1406         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1407             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1408             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1409             break;
1410         case HCI_INIT_WRITE_LOCAL_NAME: {
1411             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1412             hci_reserve_packet_buffer();
1413             uint8_t * packet = hci_stack->hci_packet_buffer;
1414             // construct HCI Command and send
1415             uint16_t opcode = hci_write_local_name.opcode;
1416             hci_stack->last_cmd_opcode = opcode;
1417             packet[0] = opcode & 0xff;
1418             packet[1] = opcode >> 8;
1419             packet[2] = DEVICE_NAME_LEN;
1420             memset(&packet[3], 0, DEVICE_NAME_LEN);
1421             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1422             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1423             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1424             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1425             // expand '00:00:00:00:00:00' in name with bd_addr
1426             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1427             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1428             break;
1429         }
1430         case HCI_INIT_WRITE_EIR_DATA: {
1431             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1432             hci_reserve_packet_buffer();
1433             uint8_t * packet = hci_stack->hci_packet_buffer;
1434             // construct HCI Command in-place and send
1435             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1436             hci_stack->last_cmd_opcode = opcode;
1437             uint16_t offset = 0;
1438             packet[offset++] = opcode & 0xff;
1439             packet[offset++] = opcode >> 8;
1440             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1441             packet[offset++] = 0;  // FEC not required
1442             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1443             if (hci_stack->eir_data){
1444                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1445                 ad_context_t context;
1446                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1447                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1448                     uint8_t size        = ad_iterator_get_data_len(&context);
1449                     const uint8_t *data = ad_iterator_get_data(&context);
1450                     // copy item
1451                     packet[offset++] = size + 1;
1452                     packet[offset++] = data_type;
1453                     memcpy(&packet[offset], data, size);
1454                     // update name item
1455                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1456                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1457                     }
1458                     offset += size;
1459                 }
1460             } else {
1461                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1462                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1463                 packet[offset++] = bytes_to_copy + 1;
1464                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1465                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1466                 // expand '00:00:00:00:00:00' in name with bd_addr
1467                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1468             }
1469             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1470             break;
1471         }
1472         case HCI_INIT_WRITE_INQUIRY_MODE:
1473             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1474             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1475             break;
1476         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1477             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1478             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1479             break;
1480         case HCI_INIT_WRITE_SCAN_ENABLE:
1481             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1482             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1483             break;
1484         // only sent if ENABLE_SCO_OVER_HCI is defined
1485         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1487             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1488             break;
1489         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1490             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1491             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1492             break;
1493         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1494         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1495             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1496             log_info("BCM: Route SCO data via HCI transport");
1497             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1498             break;
1499 
1500 #endif
1501 #ifdef ENABLE_BLE
1502         // LE INIT
1503         case HCI_INIT_LE_READ_BUFFER_SIZE:
1504             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1505             hci_send_cmd(&hci_le_read_buffer_size);
1506             break;
1507         case HCI_INIT_LE_SET_EVENT_MASK:
1508             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1509             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1510             break;
1511         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1512             // LE Supported Host = 1, Simultaneous Host = 0
1513             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1514             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1515             break;
1516 #endif
1517 
1518 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1519         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1520             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1521             hci_send_cmd(&hci_le_read_maximum_data_length);
1522             break;
1523         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1524             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1525             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1526             break;
1527 #endif
1528 
1529 #ifdef ENABLE_LE_CENTRAL
1530         case HCI_INIT_READ_WHITE_LIST_SIZE:
1531             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1532             hci_send_cmd(&hci_le_read_white_list_size);
1533             break;
1534         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1535             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1536             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);
1537             break;
1538 #endif
1539         default:
1540             return;
1541     }
1542 }
1543 
1544 static void hci_init_done(void){
1545     // done. tell the app
1546     log_info("hci_init_done -> HCI_STATE_WORKING");
1547     hci_stack->state = HCI_STATE_WORKING;
1548     hci_emit_state();
1549     hci_run();
1550 }
1551 
1552 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1553     bool command_completed = false;
1554     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1555         uint16_t opcode = little_endian_read_16(packet,3);
1556         if (opcode == hci_stack->last_cmd_opcode){
1557             command_completed = true;
1558             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1559         } else {
1560             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1561         }
1562     }
1563 
1564     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1565         uint8_t  status = packet[2];
1566         uint16_t opcode = little_endian_read_16(packet,4);
1567         if (opcode == hci_stack->last_cmd_opcode){
1568             if (status){
1569                 command_completed = true;
1570                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1571             } else {
1572                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1573             }
1574         } else {
1575             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1576         }
1577     }
1578 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1579     // Vendor == CSR
1580     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1581         // TODO: track actual command
1582         command_completed = true;
1583     }
1584 
1585     // Vendor == Toshiba
1586     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1587         // TODO: track actual command
1588         command_completed = true;
1589         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1590         hci_stack->num_cmd_packets = 1;
1591     }
1592 #endif
1593 
1594     return command_completed;
1595 }
1596 
1597 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1598 
1599     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1600 
1601     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1602 
1603 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1604 
1605     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1606     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1607     //
1608     // HCI Reset
1609     // Timeout 100 ms
1610     // HCI Reset
1611     // Command Complete Reset
1612     // HCI Read Local Version Information
1613     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1614     // hang...
1615     //
1616     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1617     if (!command_completed
1618             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1619             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1620 
1621         uint16_t opcode = little_endian_read_16(packet,3);
1622         if (opcode == hci_reset.opcode){
1623             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1624             return;
1625         }
1626     }
1627 
1628     // CSR & H5
1629     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1630     if (!command_completed
1631             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1632             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1633 
1634         uint16_t opcode = little_endian_read_16(packet,3);
1635         if (opcode == hci_reset.opcode){
1636             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1637             return;
1638         }
1639     }
1640 
1641     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1642     // fix: Correct substate and behave as command below
1643     if (command_completed){
1644         switch (hci_stack->substate){
1645             case HCI_INIT_SEND_RESET:
1646                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1647                 break;
1648             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1649                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1650                 break;
1651             default:
1652                 break;
1653         }
1654     }
1655 
1656 #endif
1657 
1658     if (!command_completed) return;
1659 
1660     bool need_baud_change = false;
1661     bool need_addr_change = false;
1662 
1663 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1664     need_baud_change = hci_stack->config
1665                         && hci_stack->chipset
1666                         && hci_stack->chipset->set_baudrate_command
1667                         && hci_stack->hci_transport->set_baudrate
1668                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1669 
1670     need_addr_change = hci_stack->custom_bd_addr_set
1671                         && hci_stack->chipset
1672                         && hci_stack->chipset->set_bd_addr_command;
1673 #endif
1674 
1675     switch(hci_stack->substate){
1676 
1677 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1678         case HCI_INIT_SEND_RESET:
1679             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1680             // fix: just correct substate and behave as command below
1681             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1682             btstack_run_loop_remove_timer(&hci_stack->timeout);
1683             break;
1684         case HCI_INIT_W4_SEND_RESET:
1685             btstack_run_loop_remove_timer(&hci_stack->timeout);
1686             break;
1687         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1688             log_info("Received local name, need baud change %d", (int) need_baud_change);
1689             if (need_baud_change){
1690                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1691                 return;
1692             }
1693             // skip baud change
1694             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1695             return;
1696         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1697             // for STLC2500D, baud rate change already happened.
1698             // for others, baud rate gets changed now
1699             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1700                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1701                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1702                 hci_stack->hci_transport->set_baudrate(baud_rate);
1703             }
1704             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1705             return;
1706         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1707             btstack_run_loop_remove_timer(&hci_stack->timeout);
1708             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1709             return;
1710         case HCI_INIT_W4_CUSTOM_INIT:
1711             // repeat custom init
1712             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1713             return;
1714 #else
1715         case HCI_INIT_W4_SEND_RESET:
1716             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1717             return ;
1718 #endif
1719 
1720         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1721             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1722               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1723                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1724                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1725                 return;
1726             }
1727             if (need_addr_change){
1728                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1729                 return;
1730             }
1731             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1732             return;
1733 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1734         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1735             if (need_baud_change){
1736                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1737                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1738                 hci_stack->hci_transport->set_baudrate(baud_rate);
1739             }
1740             if (need_addr_change){
1741                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1742                 return;
1743             }
1744             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1745             return;
1746         case HCI_INIT_W4_SET_BD_ADDR:
1747             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1748             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1749             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1750                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1751                 return;
1752             }
1753             // skipping st warm boot
1754             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1755             return;
1756         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1757             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1758             return;
1759 #endif
1760         case HCI_INIT_W4_READ_BD_ADDR:
1761 #ifdef ENABLE_CLASSIC
1762             // only read buffer size if supported
1763             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1764                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1765                 return;
1766             }
1767 #endif
1768             // skipping read buffer size
1769             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1770             return;
1771         case HCI_INIT_W4_SET_EVENT_MASK:
1772             // skip Classic init commands for LE only chipsets
1773             if (!hci_classic_supported()){
1774 #ifdef ENABLE_BLE
1775                 if (hci_le_supported()){
1776                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1777                     return;
1778                 }
1779 #endif
1780                 log_error("Neither BR/EDR nor LE supported");
1781                 hci_init_done();
1782                 return;
1783             }
1784             if (!gap_ssp_supported()){
1785                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1786                 return;
1787             }
1788             break;
1789 #ifdef ENABLE_BLE
1790         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1791             // skip write le host if not supported (e.g. on LE only EM9301)
1792             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1793             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1794             return;
1795 
1796 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1797         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1798             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1799             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1800                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1801                 return;
1802             }
1803             // explicit fall through to reduce repetitions
1804 
1805 #ifdef ENABLE_LE_CENTRAL
1806             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1807 #else
1808             hci_init_done();
1809 #endif
1810             return;
1811 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1812 
1813 #endif  /* ENABLE_BLE */
1814 
1815         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1816             // skip write secure connections host support if not supported or disabled
1817             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1818                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1819                 return;
1820             }
1821             break;
1822 
1823 #ifdef ENABLE_SCO_OVER_HCI
1824         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1825             // skip write synchronous flow control if not supported
1826             if (hci_stack->local_supported_commands[0] & 0x04) break;
1827             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1828 
1829             /* fall through */
1830 
1831         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1832             // skip write default erroneous data reporting if not supported
1833             if (hci_stack->local_supported_commands[0] & 0x08) break;
1834             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1835 
1836             /* fall through */
1837 
1838         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1839             // skip bcm set sco pcm config on non-Broadcom chipsets
1840             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1841             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1842 
1843             /* fall through */
1844 
1845         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1846             if (!hci_le_supported()){
1847                 // SKIP LE init for Classic only configuration
1848                 hci_init_done();
1849                 return;
1850             }
1851             break;
1852 
1853 #else /* !ENABLE_SCO_OVER_HCI */
1854 
1855         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1856 #ifdef ENABLE_BLE
1857             if (hci_le_supported()){
1858                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1859                 return;
1860             }
1861 #endif
1862             // SKIP LE init for Classic only configuration
1863             hci_init_done();
1864             return;
1865 #endif /* ENABLE_SCO_OVER_HCI */
1866 
1867 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1868 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1869         // Response to command before init done state -> init done
1870         case (HCI_INIT_DONE-1):
1871             hci_init_done();
1872             return;
1873 #endif
1874 
1875         default:
1876             break;
1877     }
1878     hci_initializing_next_state();
1879 }
1880 
1881 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1882     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1883     bd_addr_t bd_address;
1884     (void)memcpy(&bd_address, conn->address, 6);
1885 
1886 #ifdef ENABLE_CLASSIC
1887     // cache needed data
1888     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1889 #endif
1890 
1891     // connection failed, remove entry
1892     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1893     btstack_memory_hci_connection_free( conn );
1894 
1895 #ifdef ENABLE_CLASSIC
1896     // notify client if dedicated bonding
1897     if (notify_dedicated_bonding_failed){
1898         log_info("hci notify_dedicated_bonding_failed");
1899         hci_emit_dedicated_bonding_result(bd_address, status);
1900     }
1901 
1902     // if authentication error, also delete link key
1903     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1904         gap_drop_link_key_for_bd_addr(bd_address);
1905     }
1906 #else
1907     UNUSED(status);
1908 #endif
1909 }
1910 
1911 #ifdef ENABLE_CLASSIC
1912 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1913     // SSP Controller
1914     if (features[6] & (1 << 3)){
1915         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1916     }
1917     // eSCO
1918     if (features[3] & (1<<7)){
1919         conn->remote_supported_features[0] |= 1;
1920     }
1921     // Extended features
1922     if (features[7] & (1<<7)){
1923         conn->remote_supported_features[0] |= 2;
1924     }
1925 }
1926 
1927 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1928     // SSP Host
1929     if (features[0] & (1 << 0)){
1930         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1931     }
1932     // SC Host
1933     if (features[0] & (1 << 3)){
1934         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1935     }
1936 }
1937 
1938 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1939     // SC Controller
1940     if (features[1] & (1 << 0)){
1941         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1942     }
1943 }
1944 
1945 static void hci_handle_remote_features_received(hci_connection_t * conn){
1946     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1947     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1948     if (conn->bonding_flags & BONDING_DEDICATED){
1949         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1950     }
1951 }
1952 #endif
1953 
1954 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1955     // handle BT initialization
1956     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1957         hci_initializing_event_handler(packet, size);
1958     }
1959 
1960     // help with BT sleep
1961     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1962         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1963         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1964         hci_initializing_next_state();
1965     }
1966 }
1967 
1968 #ifdef ENABLE_CLASSIC
1969 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1970     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1971     conn->encryption_key_size = encryption_key_size;
1972 
1973     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1974         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1975         return;
1976     }
1977 
1978     // Request Authentication if not already done
1979     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1980     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1981 }
1982 #endif
1983 
1984 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1985     UNUSED(size);
1986 
1987     uint16_t manufacturer;
1988 #ifdef ENABLE_CLASSIC
1989     hci_con_handle_t handle;
1990     hci_connection_t * conn;
1991     uint8_t status;
1992 #endif
1993     // get num cmd packets - limit to 1 to reduce complexity
1994     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1995 
1996     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
1997     switch (opcode){
1998         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
1999             if (packet[5]) break;
2000             // terminate, name 248 chars
2001             packet[6+248] = 0;
2002             log_info("local name: %s", &packet[6]);
2003             break;
2004         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2005             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2006             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2007                 uint16_t acl_len = little_endian_read_16(packet, 6);
2008                 uint16_t sco_len = packet[8];
2009 
2010                 // determine usable ACL/SCO payload size
2011                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2012                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2013 
2014                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2015                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2016 
2017                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2018                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2019                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2020             }
2021             break;
2022         case HCI_OPCODE_HCI_READ_RSSI:
2023             if (packet[5] == ERROR_CODE_SUCCESS){
2024                 uint8_t event[5];
2025                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2026                 event[1] = 3;
2027                 (void)memcpy(&event[2], &packet[6], 3);
2028                 hci_emit_event(event, sizeof(event), 1);
2029             }
2030             break;
2031 #ifdef ENABLE_BLE
2032         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2033             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2034             hci_stack->le_acl_packets_total_num = packet[8];
2035             // determine usable ACL payload size
2036             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2037                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2038             }
2039             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2040             break;
2041 #endif
2042 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2043         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2044             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2045             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2046             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);
2047             break;
2048 #endif
2049 #ifdef ENABLE_LE_CENTRAL
2050         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2051             hci_stack->le_whitelist_capacity = packet[6];
2052             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2053             break;
2054 #endif
2055         case HCI_OPCODE_HCI_READ_BD_ADDR:
2056             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2057             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));
2058 #ifdef ENABLE_CLASSIC
2059             if (hci_stack->link_key_db){
2060                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2061             }
2062 #endif
2063             break;
2064 #ifdef ENABLE_CLASSIC
2065         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2066             hci_emit_discoverable_enabled(hci_stack->discoverable);
2067             break;
2068         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2069             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2070                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2071                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2072                 hci_emit_event(event, sizeof(event), 1);
2073             }
2074             break;
2075 #endif
2076         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2077             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2078 
2079 #ifdef ENABLE_CLASSIC
2080             // determine usable ACL packet types based on host buffer size and supported features
2081             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2082             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2083 #endif
2084             // Classic/LE
2085             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2086             break;
2087         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2088             manufacturer = little_endian_read_16(packet, 10);
2089             // map Cypress to Broadcom
2090             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2091                 log_info("Treat Cypress as Broadcom");
2092                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2093                 little_endian_store_16(packet, 10, manufacturer);
2094             }
2095             hci_stack->manufacturer = manufacturer;
2096             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2097             break;
2098         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2099             hci_stack->local_supported_commands[0] =
2100                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2101                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2102                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2103                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2104                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2105                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2106                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2107                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2108             hci_stack->local_supported_commands[1] =
2109                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2110                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2111                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u);   // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2112             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2113             break;
2114 #ifdef ENABLE_CLASSIC
2115         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2116             if (packet[5]) return;
2117             hci_stack->synchronous_flow_control_enabled = 1;
2118             break;
2119         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2120             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2121             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2122             conn   = hci_connection_for_handle(handle);
2123             if (conn != NULL) {
2124                 uint8_t key_size = 0;
2125                 if (status == 0){
2126                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2127                     log_info("Handle %04x key Size: %u", handle, key_size);
2128                 } else {
2129                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2130                 }
2131                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2132             }
2133             break;
2134 #endif
2135         default:
2136             break;
2137     }
2138 }
2139 
2140 static void event_handler(uint8_t *packet, uint16_t size){
2141 
2142     uint16_t event_length = packet[1];
2143 
2144     // assert packet is complete
2145     if (size != (event_length + 2u)){
2146         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2147         return;
2148     }
2149 
2150     bd_addr_t addr;
2151     bd_addr_type_t addr_type;
2152     hci_con_handle_t handle;
2153     hci_connection_t * conn;
2154     int i;
2155     int create_connection_cmd;
2156 
2157 #ifdef ENABLE_CLASSIC
2158     uint8_t link_type;
2159 #endif
2160 
2161     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2162 
2163     switch (hci_event_packet_get_type(packet)) {
2164 
2165         case HCI_EVENT_COMMAND_COMPLETE:
2166             handle_command_complete_event(packet, size);
2167             break;
2168 
2169         case HCI_EVENT_COMMAND_STATUS:
2170             // get num cmd packets - limit to 1 to reduce complexity
2171             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2172 
2173             // check command status to detected failed outgoing connections
2174             create_connection_cmd = 0;
2175 #ifdef ENABLE_CLASSIC
2176             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2177                 create_connection_cmd = 1;
2178             }
2179 #endif
2180 #ifdef ENABLE_LE_CENTRAL
2181             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2182                 create_connection_cmd = 1;
2183             }
2184 #endif
2185             if (create_connection_cmd) {
2186                 uint8_t status = hci_event_command_status_get_status(packet);
2187                 addr_type = hci_stack->outgoing_addr_type;
2188                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2189                 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);
2190 
2191                 // reset outgoing address info
2192                 memset(hci_stack->outgoing_addr, 0, 6);
2193                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2194 
2195                 // on error
2196                 if (status != ERROR_CODE_SUCCESS){
2197 #ifdef ENABLE_LE_CENTRAL
2198                     if (hci_is_le_connection_type(addr_type)){
2199                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2200                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2201                     }
2202 #endif
2203                     // error => outgoing connection failed
2204                     if (conn != NULL){
2205                         hci_handle_connection_failed(conn, status);
2206                     }
2207                 }
2208             }
2209             break;
2210 
2211         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2212             if (size < 3) return;
2213             uint16_t num_handles = packet[2];
2214             if (size != (3u + num_handles * 4u)) return;
2215             uint16_t offset = 3;
2216             for (i=0; i<num_handles;i++){
2217                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2218                 offset += 2u;
2219                 uint16_t num_packets = little_endian_read_16(packet, offset);
2220                 offset += 2u;
2221 
2222                 conn = hci_connection_for_handle(handle);
2223                 if (!conn){
2224                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2225                     continue;
2226                 }
2227 
2228                 if (conn->num_packets_sent >= num_packets){
2229                     conn->num_packets_sent -= num_packets;
2230                 } else {
2231                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2232                     conn->num_packets_sent = 0;
2233                 }
2234                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2235 
2236 #ifdef ENABLE_CLASSIC
2237                 // For SCO, we do the can_send_now_check here
2238                 hci_notify_if_sco_can_send_now();
2239 #endif
2240             }
2241             break;
2242         }
2243 
2244 #ifdef ENABLE_CLASSIC
2245         case HCI_EVENT_INQUIRY_COMPLETE:
2246             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2247                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2248                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2249                 hci_emit_event(event, sizeof(event), 1);
2250             }
2251             break;
2252         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2253             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2254                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2255             }
2256             break;
2257         case HCI_EVENT_CONNECTION_REQUEST:
2258             reverse_bd_addr(&packet[2], addr);
2259             if (hci_stack->gap_classic_accept_callback != NULL){
2260                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2261                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2262                     bd_addr_copy(hci_stack->decline_addr, addr);
2263                     break;
2264                 }
2265             }
2266 
2267             // TODO: eval COD 8-10
2268             link_type = packet[11];
2269             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2270             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2271             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2272             if (!conn) {
2273                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2274             }
2275             if (!conn) {
2276                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2277                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2278                 bd_addr_copy(hci_stack->decline_addr, addr);
2279                 break;
2280             }
2281             conn->role  = HCI_ROLE_SLAVE;
2282             conn->state = RECEIVED_CONNECTION_REQUEST;
2283             // store info about eSCO
2284             if (link_type == 0x02){
2285                 conn->remote_supported_features[0] |= 1;
2286             }
2287             hci_run();
2288             break;
2289 
2290         case HCI_EVENT_CONNECTION_COMPLETE:
2291             // Connection management
2292             reverse_bd_addr(&packet[5], addr);
2293             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2294             addr_type = BD_ADDR_TYPE_ACL;
2295             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2296             if (conn) {
2297                 if (!packet[2]){
2298                     conn->state = OPEN;
2299                     conn->con_handle = little_endian_read_16(packet, 3);
2300 
2301                     // queue get remote feature
2302                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2303 
2304                     // queue set supervision timeout if we're master
2305                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2306                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2307                     }
2308 
2309                     // restart timer
2310                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2311                     btstack_run_loop_add_timer(&conn->timeout);
2312 
2313                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2314 
2315                     hci_emit_nr_connections_changed();
2316                 } else {
2317                     // connection failed
2318                     hci_handle_connection_failed(conn, packet[2]);
2319                 }
2320             }
2321             break;
2322 
2323         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2324             reverse_bd_addr(&packet[5], addr);
2325             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2326             if (packet[2]){
2327                 // connection failed
2328                 break;
2329             }
2330             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2331             if (!conn) {
2332                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2333             }
2334             if (!conn) {
2335                 break;
2336             }
2337             conn->state = OPEN;
2338             conn->con_handle = little_endian_read_16(packet, 3);
2339 
2340 #ifdef ENABLE_SCO_OVER_HCI
2341             // update SCO
2342             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2343                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2344             }
2345             // trigger can send now
2346             if (hci_have_usb_transport()){
2347                 hci_stack->sco_can_send_now = 1;
2348             }
2349 #endif
2350             break;
2351 
2352         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2353             handle = little_endian_read_16(packet, 3);
2354             conn = hci_connection_for_handle(handle);
2355             if (!conn) break;
2356             if (!packet[2]){
2357                 const uint8_t * features = &packet[5];
2358                 hci_handle_remote_features_page_0(conn, features);
2359 
2360                 // read extended features if possible
2361                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2362                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2363                     break;
2364                 }
2365             }
2366             hci_handle_remote_features_received(conn);
2367             break;
2368 
2369         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2370             handle = little_endian_read_16(packet, 3);
2371             conn = hci_connection_for_handle(handle);
2372             if (!conn) break;
2373             // status = ok, page = 1
2374             if (!packet[2]) {
2375                 uint8_t page_number = packet[5];
2376                 uint8_t maximum_page_number = packet[6];
2377                 const uint8_t * features = &packet[7];
2378                 bool done = false;
2379                 switch (page_number){
2380                     case 1:
2381                         hci_handle_remote_features_page_1(conn, features);
2382                         if (maximum_page_number >= 2){
2383                             // get Secure Connections (Controller) from Page 2 if available
2384                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2385                         } else {
2386                             // otherwise, assume SC (Controller) == SC (Host)
2387                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2388                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2389                             }
2390                             done = true;
2391                         }
2392                         break;
2393                     case 2:
2394                         hci_handle_remote_features_page_2(conn, features);
2395                         done = true;
2396                         break;
2397                     default:
2398                         break;
2399                 }
2400                 if (!done) break;
2401             }
2402             hci_handle_remote_features_received(conn);
2403             break;
2404 
2405         case HCI_EVENT_LINK_KEY_REQUEST:
2406             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2407             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2408             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2409             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2410             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2411             hci_run();
2412             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2413             return;
2414 
2415         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2416             reverse_bd_addr(&packet[2], addr);
2417             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2418             if (!conn) break;
2419             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2420             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2421             // Change Connection Encryption keeps link key type
2422             if (link_key_type != CHANGED_COMBINATION_KEY){
2423                 conn->link_key_type = link_key_type;
2424             }
2425             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2426             // still forward event to allow dismiss of pairing dialog
2427             break;
2428         }
2429 
2430         case HCI_EVENT_PIN_CODE_REQUEST:
2431             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2432             // non-bondable mode: pin code negative reply will be sent
2433             if (!hci_stack->bondable){
2434                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2435                 hci_run();
2436                 return;
2437             }
2438             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2439             if (!hci_stack->link_key_db) break;
2440             hci_event_pin_code_request_get_bd_addr(packet, addr);
2441             hci_stack->link_key_db->delete_link_key(addr);
2442             break;
2443 
2444         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2445             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2446             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2447             break;
2448 
2449         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2450             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2451             if (!hci_stack->ssp_auto_accept) break;
2452             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2453             break;
2454 
2455         case HCI_EVENT_USER_PASSKEY_REQUEST:
2456             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2457             if (!hci_stack->ssp_auto_accept) break;
2458             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2459             break;
2460         case HCI_EVENT_MODE_CHANGE:
2461             handle = hci_event_mode_change_get_handle(packet);
2462             conn = hci_connection_for_handle(handle);
2463             if (!conn) break;
2464             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2465             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2466             break;
2467 #endif
2468 
2469         case HCI_EVENT_ENCRYPTION_CHANGE:
2470             handle = hci_event_encryption_change_get_connection_handle(packet);
2471             conn = hci_connection_for_handle(handle);
2472             if (!conn) break;
2473             if (hci_event_encryption_change_get_status(packet) == 0u) {
2474                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2475                 if (encryption_enabled){
2476                     if (hci_is_le_connection(conn)){
2477                         // For LE, we accept connection as encrypted
2478                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2479                     }
2480 #ifdef ENABLE_CLASSIC
2481                     else {
2482                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2483                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2484                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2485                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2486                             log_info("SC during pairing, but only E0 now -> abort");
2487                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2488                             break;
2489                         }
2490 
2491                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2492                         if (connected_uses_aes_ccm){
2493                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2494                         }
2495 
2496                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2497                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2498                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2499                         } else {
2500                             // if not, pretend everything is perfect
2501                             hci_handle_read_encryption_key_size_complete(conn, 16);
2502                         }
2503                     }
2504 #endif
2505                 } else {
2506                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2507                 }
2508             }
2509 
2510             break;
2511 
2512 #ifdef ENABLE_CLASSIC
2513         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2514             handle = hci_event_authentication_complete_get_connection_handle(packet);
2515             conn = hci_connection_for_handle(handle);
2516             if (!conn) break;
2517 
2518             // ignore authentication event if we didn't request it
2519             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2520 
2521             // dedicated bonding: send result and disconnect
2522             if (conn->bonding_flags & BONDING_DEDICATED){
2523                 conn->bonding_flags &= ~BONDING_DEDICATED;
2524                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2525                 conn->bonding_status = packet[2];
2526                 break;
2527             }
2528 
2529             // authenticated only if auth status == 0
2530             if (hci_event_authentication_complete_get_status(packet) == 0){
2531                 // authenticated
2532                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2533 
2534                 // If link key sufficient for requested security and not already encrypted, start encryption
2535                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2536                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2537                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2538                     break;
2539                 }
2540             }
2541 
2542             // emit updated security level
2543             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2544             break;
2545 #endif
2546 
2547         // HCI_EVENT_DISCONNECTION_COMPLETE
2548         // has been split, to first notify stack before shutting connection down
2549         // see end of function, too.
2550         case HCI_EVENT_DISCONNECTION_COMPLETE:
2551             if (packet[2]) break;   // status != 0
2552             handle = little_endian_read_16(packet, 3);
2553             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2554             if (hci_stack->acl_fragmentation_total_size > 0u) {
2555                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2556                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2557                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2558                     hci_stack->acl_fragmentation_total_size = 0;
2559                     hci_stack->acl_fragmentation_pos = 0;
2560                     if (release_buffer){
2561                         hci_release_packet_buffer();
2562                     }
2563                 }
2564             }
2565 
2566             conn = hci_connection_for_handle(handle);
2567             if (!conn) break;
2568             // mark connection for shutdown
2569             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2570 
2571             // emit dedicatd bonding event
2572             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2573                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2574             }
2575 
2576 #ifdef ENABLE_BLE
2577 #ifdef ENABLE_LE_PERIPHERAL
2578             // re-enable advertisements for le connections if active
2579             if (hci_is_le_connection(conn)){
2580                 hci_update_advertisements_enabled_for_current_roles();
2581             }
2582 #endif
2583 #endif
2584             break;
2585 
2586         case HCI_EVENT_HARDWARE_ERROR:
2587             log_error("Hardware Error: 0x%02x", packet[2]);
2588             if (hci_stack->hardware_error_callback){
2589                 (*hci_stack->hardware_error_callback)(packet[2]);
2590             } else {
2591                 // if no special requests, just reboot stack
2592                 hci_power_control_off();
2593                 hci_power_control_on();
2594             }
2595             break;
2596 
2597 #ifdef ENABLE_CLASSIC
2598         case HCI_EVENT_ROLE_CHANGE:
2599             if (packet[2]) break;   // status != 0
2600             reverse_bd_addr(&packet[3], addr);
2601             addr_type = BD_ADDR_TYPE_ACL;
2602             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2603             if (!conn) break;
2604             conn->role = packet[9];
2605             break;
2606 #endif
2607 
2608         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2609             // release packet buffer only for asynchronous transport and if there are not further fragements
2610             if (hci_transport_synchronous()) {
2611                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2612                 return; // instead of break: to avoid re-entering hci_run()
2613             }
2614             hci_stack->acl_fragmentation_tx_active = 0;
2615             if (hci_stack->acl_fragmentation_total_size) break;
2616             hci_release_packet_buffer();
2617 
2618             // L2CAP receives this event via the hci_emit_event below
2619 
2620 #ifdef ENABLE_CLASSIC
2621             // For SCO, we do the can_send_now_check here
2622             hci_notify_if_sco_can_send_now();
2623 #endif
2624             break;
2625 
2626 #ifdef ENABLE_CLASSIC
2627         case HCI_EVENT_SCO_CAN_SEND_NOW:
2628             // For SCO, we do the can_send_now_check here
2629             hci_stack->sco_can_send_now = 1;
2630             hci_notify_if_sco_can_send_now();
2631             return;
2632 
2633         // explode inquriy results for easier consumption
2634         case HCI_EVENT_INQUIRY_RESULT:
2635         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2636         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2637             gap_inquiry_explode(packet, size);
2638             break;
2639 #endif
2640 
2641 #ifdef ENABLE_BLE
2642         case HCI_EVENT_LE_META:
2643             switch (packet[2]){
2644 #ifdef ENABLE_LE_CENTRAL
2645                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2646                     // log_info("advertising report received");
2647                     if (!hci_stack->le_scanning_enabled) break;
2648                     le_handle_advertisement_report(packet, size);
2649                     break;
2650 #endif
2651                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2652                     // Connection management
2653                     reverse_bd_addr(&packet[8], addr);
2654                     addr_type = (bd_addr_type_t)packet[7];
2655                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2656                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2657 
2658 #ifdef ENABLE_LE_CENTRAL
2659                     // handle error: error is reported only to the initiator -> outgoing connection
2660                     if (packet[3]){
2661 
2662                         // handle cancelled outgoing connection
2663                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2664                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2665                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2666                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2667                             // whitelist connect
2668                             if (hci_is_le_connection_type(addr_type)){
2669                                 hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2670                                 hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2671                             }
2672                             // get outgoing connection conn struct for direct connect
2673                             conn = gap_get_outgoing_connection();
2674                         }
2675 
2676                         // outgoing le connection establishment is done
2677                         if (conn){
2678                             // remove entry
2679                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2680                             btstack_memory_hci_connection_free( conn );
2681                         }
2682                         break;
2683                     }
2684 #endif
2685 
2686                     // on success, both hosts receive connection complete event
2687                     if (packet[6] == HCI_ROLE_MASTER){
2688 #ifdef ENABLE_LE_CENTRAL
2689                         // if we're master on an le connection, it was an outgoing connection and we're done with it
2690                         // note: no hci_connection_t object exists yet for connect with whitelist
2691                         if (hci_is_le_connection_type(addr_type)){
2692                             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2693                             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2694                         }
2695 #endif
2696                     } else {
2697 #ifdef ENABLE_LE_PERIPHERAL
2698                         // if we're slave, it was an incoming connection, advertisements have stopped
2699                         hci_stack->le_advertisements_active = false;
2700 #endif
2701                     }
2702                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2703                     if (!conn){
2704                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2705                     }
2706                     // no memory, sorry.
2707                     if (!conn){
2708                         break;
2709                     }
2710 
2711                     conn->state = OPEN;
2712                     conn->role  = packet[6];
2713                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2714                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2715 
2716 #ifdef ENABLE_LE_PERIPHERAL
2717                     if (packet[6] == HCI_ROLE_SLAVE){
2718                         hci_update_advertisements_enabled_for_current_roles();
2719                     }
2720 #endif
2721 
2722                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2723 
2724                     // restart timer
2725                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2726                     // btstack_run_loop_add_timer(&conn->timeout);
2727 
2728                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2729 
2730                     hci_emit_nr_connections_changed();
2731                     break;
2732 
2733                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2734                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2735                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2736                     conn = hci_connection_for_handle(handle);
2737                     if (!conn) break;
2738                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2739                     break;
2740 
2741                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2742                     // connection
2743                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2744                     conn = hci_connection_for_handle(handle);
2745                     if (conn) {
2746                         // read arguments
2747                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2748                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2749                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2750                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2751 
2752                         // validate against current connection parameter range
2753                         le_connection_parameter_range_t existing_range;
2754                         gap_get_connection_parameter_range(&existing_range);
2755                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2756                         if (update_parameter){
2757                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2758                             conn->le_conn_interval_min = le_conn_interval_min;
2759                             conn->le_conn_interval_max = le_conn_interval_max;
2760                             conn->le_conn_latency = le_conn_latency;
2761                             conn->le_supervision_timeout = le_supervision_timeout;
2762                         } else {
2763                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2764                         }
2765                     }
2766                     break;
2767 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2768                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2769                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2770                     conn = hci_connection_for_handle(handle);
2771                     if (conn) {
2772                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2773                     }
2774                     break;
2775 #endif
2776                 default:
2777                     break;
2778             }
2779             break;
2780 #endif
2781         case HCI_EVENT_VENDOR_SPECIFIC:
2782             // Vendor specific commands often create vendor specific event instead of num completed packets
2783             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2784             switch (hci_stack->manufacturer){
2785                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2786                     hci_stack->num_cmd_packets = 1;
2787                     break;
2788                 default:
2789                     break;
2790             }
2791             break;
2792         default:
2793             break;
2794     }
2795 
2796     handle_event_for_current_stack_state(packet, size);
2797 
2798     // notify upper stack
2799 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2800 
2801     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2802     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2803         if (!packet[2]){
2804             handle = little_endian_read_16(packet, 3);
2805             hci_connection_t * aConn = hci_connection_for_handle(handle);
2806             if (aConn) {
2807                 // discard connection if app did not trigger a reconnect in the event handler
2808                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2809                     hci_shutdown_connection(aConn);
2810                 }
2811             }
2812         }
2813     }
2814 
2815 	// execute main loop
2816 	hci_run();
2817 }
2818 
2819 #ifdef ENABLE_CLASSIC
2820 
2821 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2822 static void sco_schedule_tx(hci_connection_t * conn);
2823 
2824 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2825     log_debug("SCO TX Timeout");
2826     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2827     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2828     if (!conn) return;
2829 
2830     // trigger send
2831     conn->sco_tx_ready = 1;
2832     // extra packet if CVSD but SCO buffer is too short
2833     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2834         conn->sco_tx_ready++;
2835     }
2836     hci_notify_if_sco_can_send_now();
2837 }
2838 
2839 
2840 #define SCO_TX_AFTER_RX_MS (6)
2841 
2842 static void sco_schedule_tx(hci_connection_t * conn){
2843 
2844     uint32_t now = btstack_run_loop_get_time_ms();
2845     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2846     int time_delta_ms = sco_tx_ms - now;
2847 
2848     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2849 
2850     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2851     btstack_run_loop_set_timer(timer, time_delta_ms);
2852     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2853     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2854     btstack_run_loop_add_timer(timer);
2855 }
2856 
2857 static void sco_handler(uint8_t * packet, uint16_t size){
2858     // lookup connection struct
2859     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2860     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2861     if (!conn) return;
2862 
2863     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2864     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2865         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2866             packet[2] = 0x3c;
2867             memmove(&packet[3], &packet[23], 63);
2868             size = 63;
2869         }
2870     }
2871 
2872     if (hci_have_usb_transport()){
2873         // Nothing to do
2874     } else {
2875         // 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);
2876         if (hci_stack->synchronous_flow_control_enabled == 0){
2877             uint32_t now = btstack_run_loop_get_time_ms();
2878 
2879             if (!conn->sco_rx_valid){
2880                 // ignore first 10 packets
2881                 conn->sco_rx_count++;
2882                 // log_debug("sco rx count %u", conn->sco_rx_count);
2883                 if (conn->sco_rx_count == 10) {
2884                     // use first timestamp as is and pretent it just started
2885                     conn->sco_rx_ms = now;
2886                     conn->sco_rx_valid = 1;
2887                     conn->sco_rx_count = 0;
2888                     sco_schedule_tx(conn);
2889                 }
2890             } else {
2891                 // track expected arrival timme
2892                 conn->sco_rx_count++;
2893                 conn->sco_rx_ms += 7;
2894                 int delta = (int32_t) (now - conn->sco_rx_ms);
2895                 if (delta > 0){
2896                     conn->sco_rx_ms++;
2897                 }
2898                 // log_debug("sco rx %u", conn->sco_rx_ms);
2899                 sco_schedule_tx(conn);
2900             }
2901         }
2902     }
2903     // deliver to app
2904     if (hci_stack->sco_packet_handler) {
2905         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2906     }
2907 
2908 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2909     conn->num_packets_completed++;
2910     hci_stack->host_completed_packets = 1;
2911     hci_run();
2912 #endif
2913 }
2914 #endif
2915 
2916 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2917     hci_dump_packet(packet_type, 1, packet, size);
2918     switch (packet_type) {
2919         case HCI_EVENT_PACKET:
2920             event_handler(packet, size);
2921             break;
2922         case HCI_ACL_DATA_PACKET:
2923             acl_handler(packet, size);
2924             break;
2925 #ifdef ENABLE_CLASSIC
2926         case HCI_SCO_DATA_PACKET:
2927             sco_handler(packet, size);
2928             break;
2929 #endif
2930         default:
2931             break;
2932     }
2933 }
2934 
2935 /**
2936  * @brief Add event packet handler.
2937  */
2938 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2939     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2940 }
2941 
2942 
2943 /** Register HCI packet handlers */
2944 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2945     hci_stack->acl_packet_handler = handler;
2946 }
2947 
2948 #ifdef ENABLE_CLASSIC
2949 /**
2950  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2951  */
2952 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2953     hci_stack->sco_packet_handler = handler;
2954 }
2955 #endif
2956 
2957 static void hci_state_reset(void){
2958     // no connections yet
2959     hci_stack->connections = NULL;
2960 
2961     // keep discoverable/connectable as this has been requested by the client(s)
2962     // hci_stack->discoverable = 0;
2963     // hci_stack->connectable = 0;
2964     // hci_stack->bondable = 1;
2965     // hci_stack->own_addr_type = 0;
2966 
2967     // buffer is free
2968     hci_stack->hci_packet_buffer_reserved = 0;
2969 
2970     // no pending cmds
2971     hci_stack->decline_reason = 0;
2972     hci_stack->new_scan_enable_value = 0xff;
2973 
2974     // LE
2975 #ifdef ENABLE_BLE
2976     memset(hci_stack->le_random_address, 0, 6);
2977     hci_stack->le_random_address_set = 0;
2978 #endif
2979 #ifdef ENABLE_LE_CENTRAL
2980     hci_stack->le_scanning_active  = 0;
2981     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2982     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2983     hci_stack->le_whitelist_capacity = 0;
2984 #endif
2985 }
2986 
2987 #ifdef ENABLE_CLASSIC
2988 /**
2989  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2990  */
2991 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2992     // store and open remote device db
2993     hci_stack->link_key_db = link_key_db;
2994     if (hci_stack->link_key_db) {
2995         hci_stack->link_key_db->open();
2996     }
2997 }
2998 #endif
2999 
3000 void hci_init(const hci_transport_t *transport, const void *config){
3001 
3002 #ifdef HAVE_MALLOC
3003     if (!hci_stack) {
3004         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3005     }
3006 #else
3007     hci_stack = &hci_stack_static;
3008 #endif
3009     memset(hci_stack, 0, sizeof(hci_stack_t));
3010 
3011     // reference to use transport layer implementation
3012     hci_stack->hci_transport = transport;
3013 
3014     // reference to used config
3015     hci_stack->config = config;
3016 
3017     // setup pointer for outgoing packet buffer
3018     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3019 
3020     // max acl payload size defined in config.h
3021     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3022 
3023     // register packet handlers with transport
3024     transport->register_packet_handler(&packet_handler);
3025 
3026     hci_stack->state = HCI_STATE_OFF;
3027 
3028     // class of device
3029     hci_stack->class_of_device = 0x007a020c; // Smartphone
3030 
3031     // bondable by default
3032     hci_stack->bondable = 1;
3033 
3034 #ifdef ENABLE_CLASSIC
3035     // classic name
3036     hci_stack->local_name = default_classic_name;
3037 
3038     // Master slave policy
3039     hci_stack->master_slave_policy = 1;
3040 
3041     // Allow Role Switch
3042     hci_stack->allow_role_switch = 1;
3043 
3044     // Default / minimum security level = 2
3045     hci_stack->gap_security_level = LEVEL_2;
3046 
3047     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3048     hci_stack->gap_required_encyrption_key_size = 7;
3049 #endif
3050 
3051     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3052     hci_stack->ssp_enable = 1;
3053     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3054     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3055     hci_stack->ssp_auto_accept = 1;
3056 
3057     // Secure Connections: enable (requires support from Controller)
3058     hci_stack->secure_connections_enable = true;
3059 
3060     // voice setting - signed 16 bit pcm data with CVSD over the air
3061     hci_stack->sco_voice_setting = 0x60;
3062 
3063 #ifdef ENABLE_LE_CENTRAL
3064     // connection parameter to use for outgoing connections
3065     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3066     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3067     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3068     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3069     hci_stack->le_connection_latency      = 4;         // 4
3070     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3071     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3072     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3073 
3074     // default LE Scanning
3075     hci_stack->le_scan_type     =   0x1; // active
3076     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3077     hci_stack->le_scan_window   =  0x30; //  30 ms
3078 #endif
3079 
3080 #ifdef ENABLE_LE_PERIPHERAL
3081     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3082 #endif
3083 
3084     // connection parameter range used to answer connection parameter update requests in l2cap
3085     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3086     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3087     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3088     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3089     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3090     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3091 
3092     hci_state_reset();
3093 }
3094 
3095 /**
3096  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3097  */
3098 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3099     hci_stack->chipset = chipset_driver;
3100 
3101     // reset chipset driver - init is also called on power_up
3102     if (hci_stack->chipset && hci_stack->chipset->init){
3103         hci_stack->chipset->init(hci_stack->config);
3104     }
3105 }
3106 
3107 /**
3108  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3109  */
3110 void hci_set_control(const btstack_control_t *hardware_control){
3111     // references to used control implementation
3112     hci_stack->control = hardware_control;
3113     // init with transport config
3114     hardware_control->init(hci_stack->config);
3115 }
3116 
3117 void hci_close(void){
3118     // close remote device db
3119     if (hci_stack->link_key_db) {
3120         hci_stack->link_key_db->close();
3121     }
3122 
3123     btstack_linked_list_iterator_t lit;
3124     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3125     while (btstack_linked_list_iterator_has_next(&lit)){
3126         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3127         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3128         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3129         hci_shutdown_connection(connection);
3130     }
3131 
3132     hci_power_control(HCI_POWER_OFF);
3133 
3134 #ifdef HAVE_MALLOC
3135     free(hci_stack);
3136 #endif
3137     hci_stack = NULL;
3138 }
3139 
3140 #ifdef ENABLE_CLASSIC
3141 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3142     // validate ranage and set
3143     if (encryption_key_size < 7)  return;
3144     if (encryption_key_size > 16) return;
3145     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3146 }
3147 
3148 void gap_set_security_level(gap_security_level_t security_level){
3149     hci_stack->gap_security_level = security_level;
3150 }
3151 
3152 gap_security_level_t gap_get_security_level(void){
3153     return hci_stack->gap_security_level;
3154 }
3155 #endif
3156 
3157 #ifdef ENABLE_CLASSIC
3158 void gap_set_class_of_device(uint32_t class_of_device){
3159     hci_stack->class_of_device = class_of_device;
3160 }
3161 
3162 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3163     hci_stack->default_link_policy_settings = default_link_policy_settings;
3164 }
3165 
3166 void gap_set_allow_role_switch(bool allow_role_switch){
3167     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3168 }
3169 
3170 uint8_t hci_get_allow_role_switch(void){
3171     return  hci_stack->allow_role_switch;
3172 }
3173 
3174 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3175     hci_stack->link_supervision_timeout = link_supervision_timeout;
3176 }
3177 
3178 void hci_disable_l2cap_timeout_check(void){
3179     disable_l2cap_timeouts = 1;
3180 }
3181 #endif
3182 
3183 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3184 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3185 void hci_set_bd_addr(bd_addr_t addr){
3186     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3187     hci_stack->custom_bd_addr_set = 1;
3188 }
3189 #endif
3190 
3191 // State-Module-Driver overview
3192 // state                    module  low-level
3193 // HCI_STATE_OFF             off      close
3194 // HCI_STATE_INITIALIZING,   on       open
3195 // HCI_STATE_WORKING,        on       open
3196 // HCI_STATE_HALTING,        on       open
3197 // HCI_STATE_SLEEPING,    off/sleep   close
3198 // HCI_STATE_FALLING_ASLEEP  on       open
3199 
3200 static int hci_power_control_on(void){
3201 
3202     // power on
3203     int err = 0;
3204     if (hci_stack->control && hci_stack->control->on){
3205         err = (*hci_stack->control->on)();
3206     }
3207     if (err){
3208         log_error( "POWER_ON failed");
3209         hci_emit_hci_open_failed();
3210         return err;
3211     }
3212 
3213     // int chipset driver
3214     if (hci_stack->chipset && hci_stack->chipset->init){
3215         hci_stack->chipset->init(hci_stack->config);
3216     }
3217 
3218     // init transport
3219     if (hci_stack->hci_transport->init){
3220         hci_stack->hci_transport->init(hci_stack->config);
3221     }
3222 
3223     // open transport
3224     err = hci_stack->hci_transport->open();
3225     if (err){
3226         log_error( "HCI_INIT failed, turning Bluetooth off again");
3227         if (hci_stack->control && hci_stack->control->off){
3228             (*hci_stack->control->off)();
3229         }
3230         hci_emit_hci_open_failed();
3231         return err;
3232     }
3233     return 0;
3234 }
3235 
3236 static void hci_power_control_off(void){
3237 
3238     log_info("hci_power_control_off");
3239 
3240     // close low-level device
3241     hci_stack->hci_transport->close();
3242 
3243     log_info("hci_power_control_off - hci_transport closed");
3244 
3245     // power off
3246     if (hci_stack->control && hci_stack->control->off){
3247         (*hci_stack->control->off)();
3248     }
3249 
3250     log_info("hci_power_control_off - control closed");
3251 
3252     hci_stack->state = HCI_STATE_OFF;
3253 }
3254 
3255 static void hci_power_control_sleep(void){
3256 
3257     log_info("hci_power_control_sleep");
3258 
3259 #if 0
3260     // don't close serial port during sleep
3261 
3262     // close low-level device
3263     hci_stack->hci_transport->close(hci_stack->config);
3264 #endif
3265 
3266     // sleep mode
3267     if (hci_stack->control && hci_stack->control->sleep){
3268         (*hci_stack->control->sleep)();
3269     }
3270 
3271     hci_stack->state = HCI_STATE_SLEEPING;
3272 }
3273 
3274 static int hci_power_control_wake(void){
3275 
3276     log_info("hci_power_control_wake");
3277 
3278     // wake on
3279     if (hci_stack->control && hci_stack->control->wake){
3280         (*hci_stack->control->wake)();
3281     }
3282 
3283 #if 0
3284     // open low-level device
3285     int err = hci_stack->hci_transport->open(hci_stack->config);
3286     if (err){
3287         log_error( "HCI_INIT failed, turning Bluetooth off again");
3288         if (hci_stack->control && hci_stack->control->off){
3289             (*hci_stack->control->off)();
3290         }
3291         hci_emit_hci_open_failed();
3292         return err;
3293     }
3294 #endif
3295 
3296     return 0;
3297 }
3298 
3299 static void hci_power_transition_to_initializing(void){
3300     // set up state machine
3301     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3302     hci_stack->hci_packet_buffer_reserved = 0;
3303     hci_stack->state = HCI_STATE_INITIALIZING;
3304     hci_stack->substate = HCI_INIT_SEND_RESET;
3305 }
3306 
3307 int hci_power_control(HCI_POWER_MODE power_mode){
3308 
3309     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3310 
3311     int err = 0;
3312     switch (hci_stack->state){
3313 
3314         case HCI_STATE_OFF:
3315             switch (power_mode){
3316                 case HCI_POWER_ON:
3317                     err = hci_power_control_on();
3318                     if (err) {
3319                         log_error("hci_power_control_on() error %d", err);
3320                         return err;
3321                     }
3322                     hci_power_transition_to_initializing();
3323                     break;
3324                 case HCI_POWER_OFF:
3325                     // do nothing
3326                     break;
3327                 case HCI_POWER_SLEEP:
3328                     // do nothing (with SLEEP == OFF)
3329                     break;
3330             }
3331             break;
3332 
3333         case HCI_STATE_INITIALIZING:
3334             switch (power_mode){
3335                 case HCI_POWER_ON:
3336                     // do nothing
3337                     break;
3338                 case HCI_POWER_OFF:
3339                     // no connections yet, just turn it off
3340                     hci_power_control_off();
3341                     break;
3342                 case HCI_POWER_SLEEP:
3343                     // no connections yet, just turn it off
3344                     hci_power_control_sleep();
3345                     break;
3346             }
3347             break;
3348 
3349         case HCI_STATE_WORKING:
3350             switch (power_mode){
3351                 case HCI_POWER_ON:
3352                     // do nothing
3353                     break;
3354                 case HCI_POWER_OFF:
3355                     // see hci_run
3356                     hci_stack->state = HCI_STATE_HALTING;
3357                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3358                     break;
3359                 case HCI_POWER_SLEEP:
3360                     // see hci_run
3361                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3362                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3363                     break;
3364             }
3365             break;
3366 
3367         case HCI_STATE_HALTING:
3368             switch (power_mode){
3369                 case HCI_POWER_ON:
3370                     hci_power_transition_to_initializing();
3371                     break;
3372                 case HCI_POWER_OFF:
3373                     // do nothing
3374                     break;
3375                 case HCI_POWER_SLEEP:
3376                     // see hci_run
3377                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3378                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3379                     break;
3380             }
3381             break;
3382 
3383         case HCI_STATE_FALLING_ASLEEP:
3384             switch (power_mode){
3385                 case HCI_POWER_ON:
3386 
3387 #ifdef HAVE_PLATFORM_IPHONE_OS
3388                     // nothing to do, if H4 supports power management
3389                     if (btstack_control_iphone_power_management_enabled()){
3390                         hci_stack->state = HCI_STATE_INITIALIZING;
3391                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3392                         break;
3393                     }
3394 #endif
3395                     hci_power_transition_to_initializing();
3396                     break;
3397                 case HCI_POWER_OFF:
3398                     // see hci_run
3399                     hci_stack->state = HCI_STATE_HALTING;
3400                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3401                     break;
3402                 case HCI_POWER_SLEEP:
3403                     // do nothing
3404                     break;
3405             }
3406             break;
3407 
3408         case HCI_STATE_SLEEPING:
3409             switch (power_mode){
3410                 case HCI_POWER_ON:
3411 
3412 #ifdef HAVE_PLATFORM_IPHONE_OS
3413                     // nothing to do, if H4 supports power management
3414                     if (btstack_control_iphone_power_management_enabled()){
3415                         hci_stack->state = HCI_STATE_INITIALIZING;
3416                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3417                         hci_update_scan_enable();
3418                         break;
3419                     }
3420 #endif
3421                     err = hci_power_control_wake();
3422                     if (err) return err;
3423                     hci_power_transition_to_initializing();
3424                     break;
3425                 case HCI_POWER_OFF:
3426                     hci_stack->state = HCI_STATE_HALTING;
3427                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3428                     break;
3429                 case HCI_POWER_SLEEP:
3430                     // do nothing
3431                     break;
3432             }
3433             break;
3434     }
3435 
3436     // create internal event
3437 	hci_emit_state();
3438 
3439 	// trigger next/first action
3440 	hci_run();
3441 
3442     return 0;
3443 }
3444 
3445 
3446 #ifdef ENABLE_CLASSIC
3447 
3448 static void hci_update_scan_enable(void){
3449     // 2 = page scan, 1 = inq scan
3450     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3451     hci_run();
3452 }
3453 
3454 void gap_discoverable_control(uint8_t enable){
3455     if (enable) enable = 1; // normalize argument
3456 
3457     if (hci_stack->discoverable == enable){
3458         hci_emit_discoverable_enabled(hci_stack->discoverable);
3459         return;
3460     }
3461 
3462     hci_stack->discoverable = enable;
3463     hci_update_scan_enable();
3464 }
3465 
3466 void gap_connectable_control(uint8_t enable){
3467     if (enable) enable = 1; // normalize argument
3468 
3469     // don't emit event
3470     if (hci_stack->connectable == enable) return;
3471 
3472     hci_stack->connectable = enable;
3473     hci_update_scan_enable();
3474 }
3475 #endif
3476 
3477 void gap_local_bd_addr(bd_addr_t address_buffer){
3478     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3479 }
3480 
3481 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3482 static void hci_host_num_completed_packets(void){
3483 
3484     // create packet manually as arrays are not supported and num_commands should not get reduced
3485     hci_reserve_packet_buffer();
3486     uint8_t * packet = hci_get_outgoing_packet_buffer();
3487 
3488     uint16_t size = 0;
3489     uint16_t num_handles = 0;
3490     packet[size++] = 0x35;
3491     packet[size++] = 0x0c;
3492     size++;  // skip param len
3493     size++;  // skip num handles
3494 
3495     // add { handle, packets } entries
3496     btstack_linked_item_t * it;
3497     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3498         hci_connection_t * connection = (hci_connection_t *) it;
3499         if (connection->num_packets_completed){
3500             little_endian_store_16(packet, size, connection->con_handle);
3501             size += 2;
3502             little_endian_store_16(packet, size, connection->num_packets_completed);
3503             size += 2;
3504             //
3505             num_handles++;
3506             connection->num_packets_completed = 0;
3507         }
3508     }
3509 
3510     packet[2] = size - 3;
3511     packet[3] = num_handles;
3512 
3513     hci_stack->host_completed_packets = 0;
3514 
3515     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3516     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3517 
3518     // release packet buffer for synchronous transport implementations
3519     if (hci_transport_synchronous()){
3520         hci_release_packet_buffer();
3521         hci_emit_transport_packet_sent();
3522     }
3523 }
3524 #endif
3525 
3526 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3527     UNUSED(ds);
3528     hci_stack->substate = HCI_HALTING_CLOSE;
3529     // allow packet handlers to defer final shutdown
3530     hci_emit_state();
3531     hci_run();
3532 }
3533 
3534 static bool hci_run_acl_fragments(void){
3535     if (hci_stack->acl_fragmentation_total_size > 0u) {
3536         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3537         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3538         if (connection) {
3539             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3540                 hci_send_acl_packet_fragments(connection);
3541                 return true;
3542             }
3543         } else {
3544             // connection gone -> discard further fragments
3545             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3546             hci_stack->acl_fragmentation_total_size = 0;
3547             hci_stack->acl_fragmentation_pos = 0;
3548         }
3549     }
3550     return false;
3551 }
3552 
3553 #ifdef ENABLE_CLASSIC
3554 static bool hci_run_general_gap_classic(void){
3555 
3556     // decline incoming connections
3557     if (hci_stack->decline_reason){
3558         uint8_t reason = hci_stack->decline_reason;
3559         hci_stack->decline_reason = 0;
3560         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3561         return true;
3562     }
3563     // send scan enable
3564     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3565         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3566         hci_stack->new_scan_enable_value = 0xff;
3567         return true;
3568     }
3569     // start/stop inquiry
3570     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3571         uint8_t duration = hci_stack->inquiry_state;
3572         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3573         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3574         return true;
3575     }
3576     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3577         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3578         hci_send_cmd(&hci_inquiry_cancel);
3579         return true;
3580     }
3581     // remote name request
3582     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3583         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3584         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3585                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3586         return true;
3587     }
3588     // pairing
3589     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3590         uint8_t state = hci_stack->gap_pairing_state;
3591         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3592         switch (state){
3593             case GAP_PAIRING_STATE_SEND_PIN:
3594                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, hci_stack->gap_pairing_input.gap_pairing_pin);
3595                 break;
3596             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3597                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3598                 break;
3599             case GAP_PAIRING_STATE_SEND_PASSKEY:
3600                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3601                 break;
3602             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3603                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3604                 break;
3605             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3606                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3607                 break;
3608             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3609                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3610                 break;
3611             default:
3612                 break;
3613         }
3614         return true;
3615     }
3616     return false;
3617 }
3618 #endif
3619 
3620 #ifdef ENABLE_BLE
3621 static bool hci_run_general_gap_le(void){
3622 
3623     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3624 
3625     if (hci_stack->state != HCI_STATE_WORKING) return false;
3626     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3627 
3628 
3629     // Phase 1: collect what to stop
3630 
3631     bool scanning_stop = false;
3632     bool connecting_stop = false;
3633     bool advertising_stop = false;
3634 
3635 #ifndef ENABLE_LE_CENTRAL
3636     UNUSED(scanning_stop);
3637     UNUSED(connecting_stop)
3638 #endif
3639 #ifndef ENABLE_LE_PERIPHERAL
3640     UNUSED(advertising_stop);
3641 #endif
3642 
3643     // check if whitelist needs modification
3644     bool whitelist_modification_pending = false;
3645     btstack_linked_list_iterator_t lit;
3646     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3647     while (btstack_linked_list_iterator_has_next(&lit)){
3648         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3649         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3650             whitelist_modification_pending = true;
3651             break;
3652         }
3653     }
3654     // check if resolving list needs modification
3655     bool resolving_list_modification_pending = false;
3656 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3657     if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
3658         resolving_list_modification_pending = true;
3659     }
3660 #endif
3661 
3662 #ifdef ENABLE_LE_CENTRAL
3663     // scanning control
3664     if (hci_stack->le_scanning_active) {
3665         // stop if:
3666         // - parameter change required
3667         // - it's disabled
3668         // - whitelist change required but used for scanning
3669         // - resolving list modified
3670         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3671         if ((hci_stack->le_scanning_param_update) ||
3672             !hci_stack->le_scanning_enabled ||
3673             scanning_uses_whitelist ||
3674             resolving_list_modification_pending){
3675 
3676             scanning_stop = true;
3677         }
3678     }
3679 #endif
3680 
3681 #ifdef ENABLE_LE_CENTRAL
3682     // connecting control
3683     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3684         // stop connecting if:
3685         // - connecting uses white and whitelist modification pending
3686         // - if it got disabled
3687         // - resolving list modified
3688         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3689         if ((connecting_uses_whitelist && whitelist_modification_pending) ||
3690             (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
3691             resolving_list_modification_pending) {
3692 
3693             connecting_stop = true;
3694         }
3695     }
3696 #endif
3697 
3698 #ifdef ENABLE_LE_PERIPHERAL
3699     // le advertisement control
3700     if (hci_stack->le_advertisements_active){
3701         // stop if:
3702         // - parameter change required
3703         // - it's disabled
3704         // - whitelist change required but used for advertisement filter policy
3705         // - resolving list modified
3706         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3707         if ((hci_stack->le_advertisements_todo != 0) ||
3708             !hci_stack->le_advertisements_enabled_for_current_roles ||
3709             (advertising_uses_whitelist & whitelist_modification_pending) ||
3710             resolving_list_modification_pending) {
3711 
3712             advertising_stop = true;
3713         }
3714     }
3715 #endif
3716 
3717 
3718     // Phase 2: stop everything that should be off during modifications
3719 
3720 #ifdef ENABLE_LE_CENTRAL
3721     if (scanning_stop){
3722         hci_stack->le_scanning_active = false;
3723         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3724         return true;
3725     }
3726 #endif
3727 
3728 #ifdef ENABLE_LE_CENTRAL
3729     if (connecting_stop){
3730         if (hci_stack->le_connecting_state != LE_CONNECTING_CANCEL){
3731             hci_send_cmd(&hci_le_create_connection_cancel);
3732             return true;
3733         }
3734     }
3735 #endif
3736 
3737 #ifdef ENABLE_LE_PERIPHERAL
3738     if (advertising_stop){
3739         hci_stack->le_advertisements_active = false;
3740         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3741         return true;
3742     }
3743 #endif
3744 
3745     // Phase 3: modify
3746 
3747 #ifdef ENABLE_LE_CENTRAL
3748     if (hci_stack->le_scanning_param_update){
3749         hci_stack->le_scanning_param_update = false;
3750         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3751                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3752         return true;
3753     }
3754 #endif
3755 
3756 #ifdef ENABLE_LE_PERIPHERAL
3757     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3758         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3759         hci_send_cmd(&hci_le_set_advertising_parameters,
3760                      hci_stack->le_advertisements_interval_min,
3761                      hci_stack->le_advertisements_interval_max,
3762                      hci_stack->le_advertisements_type,
3763                      hci_stack->le_own_addr_type,
3764                      hci_stack->le_advertisements_direct_address_type,
3765                      hci_stack->le_advertisements_direct_address,
3766                      hci_stack->le_advertisements_channel_map,
3767                      hci_stack->le_advertisements_filter_policy);
3768         return true;
3769     }
3770     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3771         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3772         uint8_t adv_data_clean[31];
3773         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3774         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3775                      hci_stack->le_advertisements_data_len);
3776         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3777         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3778         return true;
3779     }
3780     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3781         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3782         uint8_t scan_data_clean[31];
3783         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3784         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3785                      hci_stack->le_scan_response_data_len);
3786         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3787         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3788         return true;
3789     }
3790 #endif
3791 
3792 
3793 #ifdef ENABLE_LE_CENTRAL
3794     // if connect with whitelist was active and is not cancelled yet, wait until next time
3795     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
3796 #endif
3797 
3798     // LE Whitelist Management
3799     if (whitelist_modification_pending){
3800         // add/remove entries
3801         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3802         while (btstack_linked_list_iterator_has_next(&lit)){
3803             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3804 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3805 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3806 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
3807 				return true;
3808 			}
3809             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3810 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
3811                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
3812                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3813                 return true;
3814             }
3815             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
3816 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3817 				btstack_memory_whitelist_entry_free(entry);
3818             }
3819         }
3820     }
3821 
3822 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
3823     // LE Resolving List Management
3824     uint16_t i;
3825     switch (hci_stack->le_resolving_list_state){
3826         case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
3827             // check if supported
3828             if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0){
3829                 log_info("LE Address Resolution not supported");
3830                 break;
3831             } else {
3832                 hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
3833                 hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
3834                 return true;
3835             }
3836             break;
3837         case LE_RESOLVING_LIST_READ_SIZE:
3838             hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
3839             hci_send_cmd(&hci_le_read_resolving_list_size);
3840             return true;
3841         case LE_RESOLVING_LIST_SEND_CLEAR:
3842             hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
3843             (void) memset(hci_stack->le_resolving_list_add_entries, 0xff, sizeof(hci_stack->le_resolving_list_add_entries));
3844 			(void) memset(hci_stack->le_resolving_list_remove_entries, 0, sizeof(hci_stack->le_resolving_list_remove_entries));
3845             hci_send_cmd(&hci_le_clear_resolving_list);
3846             return true;
3847 		case LE_RESOLVING_LIST_REMOVE_ENTRIES:
3848 			for (i = 0 ; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++){
3849 				uint8_t offset = i >> 3;
3850 				uint8_t mask = 1 << (i & 7);
3851 				if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
3852 				hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
3853 				bd_addr_t peer_identity_addreses;
3854 				int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3855 				sm_key_t peer_irk;
3856 				le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3857 				if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3858 
3859 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
3860 				// trigger whitelist entry 'update' (work around for controller bug)
3861 				btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3862 				while (btstack_linked_list_iterator_has_next(&lit)) {
3863 					whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
3864 					if (entry->address_type != peer_identity_addr_type) continue;
3865 					if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
3866 					log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
3867 					entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
3868 				}
3869 #endif
3870 
3871 				hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type, peer_identity_addreses);
3872 				return true;
3873 			}
3874 
3875 			hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
3876 
3877 			/* fall through */
3878 
3879 		case LE_RESOLVING_LIST_ADD_ENTRIES:
3880             for (i = 0 ; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++){
3881                 uint8_t offset = i >> 3;
3882                 uint8_t mask = 1 << (i & 7);
3883                 if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
3884                 hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
3885                 bd_addr_t peer_identity_addreses;
3886                 int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
3887                 sm_key_t peer_irk;
3888                 le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
3889                 if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
3890                 const uint8_t * local_irk = gap_get_persistent_irk();
3891                 // command uses format specifier 'P' that stores 16-byte value without flip
3892                 uint8_t local_irk_flipped[16];
3893                 uint8_t peer_irk_flipped[16];
3894                 reverse_128(local_irk, local_irk_flipped);
3895                 reverse_128(peer_irk, peer_irk_flipped);
3896                 hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses, peer_irk_flipped, local_irk_flipped);
3897                 return true;
3898             }
3899 			hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3900 			break;
3901 
3902 		default:
3903             break;
3904     }
3905     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
3906 #endif
3907 
3908     // Phase 4: restore state
3909 
3910 #ifdef ENABLE_LE_CENTRAL
3911     // re-start scanning
3912     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3913         hci_stack->le_scanning_active = true;
3914         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3915         return true;
3916     }
3917 #endif
3918 
3919 #ifdef ENABLE_LE_CENTRAL
3920     // re-start connecting
3921     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3922         bd_addr_t null_addr;
3923         memset(null_addr, 0, 6);
3924         hci_send_cmd(&hci_le_create_connection,
3925                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3926                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3927                      1,         // use whitelist
3928                      0,         // peer address type
3929                      null_addr, // peer bd addr
3930                      hci_stack->le_own_addr_type, // our addr type:
3931                      hci_stack->le_connection_interval_min,    // conn interval min
3932                      hci_stack->le_connection_interval_max,    // conn interval max
3933                      hci_stack->le_connection_latency,         // conn latency
3934                      hci_stack->le_supervision_timeout,        // conn latency
3935                      hci_stack->le_minimum_ce_length,          // min ce length
3936                      hci_stack->le_maximum_ce_length           // max ce length
3937         );
3938         return true;
3939     }
3940 #endif
3941 
3942 #ifdef ENABLE_LE_PERIPHERAL
3943     // re-start advertising
3944     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
3945         // check if advertisements should be enabled given
3946         hci_stack->le_advertisements_active = true;
3947         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3948         return true;
3949     }
3950 #endif
3951 
3952     return false;
3953 }
3954 #endif
3955 
3956 static bool hci_run_general_pending_commands(void){
3957     btstack_linked_item_t * it;
3958     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3959         hci_connection_t * connection = (hci_connection_t *) it;
3960 
3961         switch(connection->state){
3962             case SEND_CREATE_CONNECTION:
3963                 switch(connection->address_type){
3964 #ifdef ENABLE_CLASSIC
3965                     case BD_ADDR_TYPE_ACL:
3966                         log_info("sending hci_create_connection");
3967                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3968                         break;
3969 #endif
3970                     default:
3971 #ifdef ENABLE_BLE
3972 #ifdef ENABLE_LE_CENTRAL
3973                         log_info("sending hci_le_create_connection");
3974                         hci_send_cmd(&hci_le_create_connection,
3975                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3976                                      hci_stack->le_connection_scan_window,      // conn scan windows
3977                                      0,         // don't use whitelist
3978                                      connection->address_type, // peer address type
3979                                      connection->address,      // peer bd addr
3980                                      hci_stack->le_own_addr_type, // our addr type:
3981                                      hci_stack->le_connection_interval_min,    // conn interval min
3982                                      hci_stack->le_connection_interval_max,    // conn interval max
3983                                      hci_stack->le_connection_latency,         // conn latency
3984                                      hci_stack->le_supervision_timeout,        // conn latency
3985                                      hci_stack->le_minimum_ce_length,          // min ce length
3986                                      hci_stack->le_maximum_ce_length          // max ce length
3987                         );
3988                         connection->state = SENT_CREATE_CONNECTION;
3989 #endif
3990 #endif
3991                         break;
3992                 }
3993                 return true;
3994 
3995 #ifdef ENABLE_CLASSIC
3996             case RECEIVED_CONNECTION_REQUEST:
3997                 connection->role  = HCI_ROLE_SLAVE;
3998                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3999                     log_info("sending hci_accept_connection_request");
4000                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4001                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4002                 }
4003                 return true;
4004 #endif
4005 
4006 #ifdef ENABLE_BLE
4007 #ifdef ENABLE_LE_CENTRAL
4008             case SEND_CANCEL_CONNECTION:
4009                 connection->state = SENT_CANCEL_CONNECTION;
4010                 hci_send_cmd(&hci_le_create_connection_cancel);
4011                 return true;
4012 #endif
4013 #endif
4014             case SEND_DISCONNECT:
4015                 connection->state = SENT_DISCONNECT;
4016                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4017                 return true;
4018 
4019             default:
4020                 break;
4021         }
4022 
4023         // no further commands if connection is about to get shut down
4024         if (connection->state == SENT_DISCONNECT) continue;
4025 
4026         if (connection->authentication_flags & READ_RSSI){
4027             connectionClearAuthenticationFlags(connection, READ_RSSI);
4028             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4029             return true;
4030         }
4031 
4032 #ifdef ENABLE_CLASSIC
4033 
4034         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4035             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4036             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4037             return true;
4038         }
4039 
4040         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
4041             log_info("responding to link key request");
4042             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4043 
4044             link_key_t link_key;
4045             link_key_type_t link_key_type;
4046             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
4047 
4048             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4049             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4050             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
4051             if (sc_downgrade){
4052                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4053                 connection->state = SENT_DISCONNECT;
4054                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4055                 return true;
4056             }
4057 
4058             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
4059             if (have_link_key && security_level_sufficient){
4060                 connection->link_key_type = link_key_type;
4061                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
4062             } else {
4063                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4064             }
4065             return true;
4066         }
4067 
4068         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4069             log_info("denying to pin request");
4070             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4071             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4072             return true;
4073         }
4074 
4075         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4076             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4077             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
4078             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
4079                 // tweak authentication requirements
4080                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
4081                 if (connection->bonding_flags & BONDING_DEDICATED){
4082                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4083                 }
4084                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4085                     authreq |= 1;
4086                 }
4087                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
4088             } else {
4089                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4090             }
4091             return true;
4092         }
4093 
4094         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4095             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4096             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4097             return true;
4098         }
4099 
4100         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4101             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4102             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4103             return true;
4104         }
4105 
4106         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4107             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4108             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4109             return true;
4110         }
4111 
4112         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4113             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4114             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4115             return true;
4116         }
4117 
4118         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4119             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4120             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4121             return true;
4122         }
4123 
4124         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4125             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4126             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4127             connection->state = SENT_DISCONNECT;
4128             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4129             return true;
4130         }
4131 
4132         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4133             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4134             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4135             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4136             return true;
4137         }
4138 
4139         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4140             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4141             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4142             return true;
4143         }
4144         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4145             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4146             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4147             return true;
4148         }
4149 #endif
4150 
4151         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4152             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4153             if (connection->state != SENT_DISCONNECT){
4154                 connection->state = SENT_DISCONNECT;
4155                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4156                 return true;
4157             }
4158         }
4159 
4160 #ifdef ENABLE_CLASSIC
4161         uint16_t sniff_min_interval;
4162         switch (connection->sniff_min_interval){
4163             case 0:
4164                 break;
4165             case 0xffff:
4166                 connection->sniff_min_interval = 0;
4167                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4168                 return true;
4169             default:
4170                 sniff_min_interval = connection->sniff_min_interval;
4171                 connection->sniff_min_interval = 0;
4172                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4173                 return true;
4174         }
4175 
4176         if (connection->request_role != HCI_ROLE_INVALID){
4177             hci_role_t  role = connection->request_role;
4178             connection->request_role = HCI_ROLE_INVALID;
4179             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4180             return true;
4181         }
4182 #endif
4183 
4184 #ifdef ENABLE_BLE
4185         switch (connection->le_con_parameter_update_state){
4186             // response to L2CAP CON PARAMETER UPDATE REQUEST
4187             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4188                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4189                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4190                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4191                              0x0000, 0xffff);
4192                 return true;
4193             case CON_PARAMETER_UPDATE_REPLY:
4194                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4195                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4196                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4197                              0x0000, 0xffff);
4198                 return true;
4199             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4200                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4201                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4202                 return true;
4203             default:
4204                 break;
4205         }
4206         if (connection->le_phy_update_all_phys != 0xffu){
4207             uint8_t all_phys = connection->le_phy_update_all_phys;
4208             connection->le_phy_update_all_phys = 0xff;
4209             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);
4210             return true;
4211         }
4212 #endif
4213     }
4214     return false;
4215 }
4216 
4217 static void hci_run(void){
4218 
4219     bool done;
4220 
4221     // send continuation fragments first, as they block the prepared packet buffer
4222     done = hci_run_acl_fragments();
4223     if (done) return;
4224 
4225 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4226     // send host num completed packets next as they don't require num_cmd_packets > 0
4227     if (!hci_can_send_comand_packet_transport()) return;
4228     if (hci_stack->host_completed_packets){
4229         hci_host_num_completed_packets();
4230         return;
4231     }
4232 #endif
4233 
4234     if (!hci_can_send_command_packet_now()) return;
4235 
4236     // global/non-connection oriented commands
4237 
4238 
4239 #ifdef ENABLE_CLASSIC
4240     // general gap classic
4241     done = hci_run_general_gap_classic();
4242     if (done) return;
4243 #endif
4244 
4245 #ifdef ENABLE_BLE
4246     // general gap le
4247     done = hci_run_general_gap_le();
4248     if (done) return;
4249 #endif
4250 
4251     // send pending HCI commands
4252     done = hci_run_general_pending_commands();
4253     if (done) return;
4254 
4255     // stack state sub statemachines
4256     hci_connection_t * connection;
4257     switch (hci_stack->state){
4258         case HCI_STATE_INITIALIZING:
4259             hci_initializing_run();
4260             break;
4261 
4262         case HCI_STATE_HALTING:
4263 
4264             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4265             switch (hci_stack->substate){
4266                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4267                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4268 
4269 #ifdef ENABLE_BLE
4270 #ifdef ENABLE_LE_CENTRAL
4271                     // free whitelist entries
4272                     {
4273                         btstack_linked_list_iterator_t lit;
4274                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4275                         while (btstack_linked_list_iterator_has_next(&lit)){
4276                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4277                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4278                             btstack_memory_whitelist_entry_free(entry);
4279                         }
4280                     }
4281 #endif
4282 #endif
4283                     // close all open connections
4284                     connection =  (hci_connection_t *) hci_stack->connections;
4285                     if (connection){
4286                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4287                         if (!hci_can_send_command_packet_now()) return;
4288 
4289                         // check state
4290                         if (connection->state == SENT_DISCONNECT) return;
4291                         connection->state = SENT_DISCONNECT;
4292 
4293                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4294 
4295                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4296                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4297 
4298                         // ... which would be ignored anyway as we shutdown (free) the connection now
4299                         hci_shutdown_connection(connection);
4300 
4301                         // finally, send the disconnect command
4302                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4303                         return;
4304                     }
4305 
4306                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4307                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4308                         log_info("HCI_STATE_HALTING: wait 50 ms");
4309                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4310                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4311                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4312                         btstack_run_loop_add_timer(&hci_stack->timeout);
4313                         break;
4314                     }
4315 
4316                     /* fall through */
4317 
4318                 case HCI_HALTING_CLOSE:
4319                     log_info("HCI_STATE_HALTING, calling off");
4320 
4321                     // switch mode
4322                     hci_power_control_off();
4323 
4324                     log_info("HCI_STATE_HALTING, emitting state");
4325                     hci_emit_state();
4326                     log_info("HCI_STATE_HALTING, done");
4327                     break;
4328 
4329                 case HCI_HALTING_W4_TIMER:
4330                     // keep waiting
4331 
4332                     break;
4333                 default:
4334                     break;
4335             }
4336 
4337             break;
4338 
4339         case HCI_STATE_FALLING_ASLEEP:
4340             switch(hci_stack->substate) {
4341                 case HCI_FALLING_ASLEEP_DISCONNECT:
4342                     log_info("HCI_STATE_FALLING_ASLEEP");
4343                     // close all open connections
4344                     connection =  (hci_connection_t *) hci_stack->connections;
4345 
4346 #ifdef HAVE_PLATFORM_IPHONE_OS
4347                     // don't close connections, if H4 supports power management
4348                     if (btstack_control_iphone_power_management_enabled()){
4349                         connection = NULL;
4350                     }
4351 #endif
4352                     if (connection){
4353 
4354                         // send disconnect
4355                         if (!hci_can_send_command_packet_now()) return;
4356 
4357                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4358                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4359 
4360                         // send disconnected event right away - causes higher layer connections to get closed, too.
4361                         hci_shutdown_connection(connection);
4362                         return;
4363                     }
4364 
4365                     if (hci_classic_supported()){
4366                         // disable page and inquiry scan
4367                         if (!hci_can_send_command_packet_now()) return;
4368 
4369                         log_info("HCI_STATE_HALTING, disabling inq scans");
4370                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4371 
4372                         // continue in next sub state
4373                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4374                         break;
4375                     }
4376 
4377                     /* fall through */
4378 
4379                 case HCI_FALLING_ASLEEP_COMPLETE:
4380                     log_info("HCI_STATE_HALTING, calling sleep");
4381 #ifdef HAVE_PLATFORM_IPHONE_OS
4382                     // don't actually go to sleep, if H4 supports power management
4383                     if (btstack_control_iphone_power_management_enabled()){
4384                         // SLEEP MODE reached
4385                         hci_stack->state = HCI_STATE_SLEEPING;
4386                         hci_emit_state();
4387                         break;
4388                     }
4389 #endif
4390                     // switch mode
4391                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4392                     hci_emit_state();
4393                     break;
4394 
4395                 default:
4396                     break;
4397             }
4398             break;
4399 
4400         default:
4401             break;
4402     }
4403 }
4404 
4405 int hci_send_cmd_packet(uint8_t *packet, int size){
4406     // house-keeping
4407 
4408 #ifdef ENABLE_CLASSIC
4409     bd_addr_t addr;
4410     hci_connection_t * conn;
4411 #endif
4412 #ifdef ENABLE_LE_CENTRAL
4413     uint8_t initiator_filter_policy;
4414 #endif
4415 
4416     uint16_t opcode = little_endian_read_16(packet, 0);
4417     switch (opcode) {
4418         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4419             hci_stack->loopback_mode = packet[3];
4420             break;
4421 
4422 #ifdef ENABLE_CLASSIC
4423         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4424             reverse_bd_addr(&packet[3], addr);
4425             log_info("Create_connection to %s", bd_addr_to_str(addr));
4426 
4427             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4428             if (!conn) {
4429                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4430                 if (!conn) {
4431                     // notify client that alloc failed
4432                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4433                     return -1; // packet not sent to controller
4434                 }
4435                 conn->state = SEND_CREATE_CONNECTION;
4436                 conn->role  = HCI_ROLE_MASTER;
4437             }
4438             log_info("conn state %u", conn->state);
4439             switch (conn->state) {
4440                 // if connection active exists
4441                 case OPEN:
4442                     // and OPEN, emit connection complete command
4443                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4444                     return -1; // packet not sent to controller
4445                 case RECEIVED_DISCONNECTION_COMPLETE:
4446                     // create connection triggered in disconnect complete event, let's do it now
4447                     break;
4448                 case SEND_CREATE_CONNECTION:
4449                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4450                     break;
4451                 default:
4452                     // otherwise, just ignore as it is already in the open process
4453                     return -1; // packet not sent to controller
4454             }
4455             conn->state = SENT_CREATE_CONNECTION;
4456 
4457             // track outgoing connection
4458             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4459             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4460             break;
4461         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4462             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4463             break;
4464         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4465             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4466             break;
4467         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4468             if (hci_stack->link_key_db) {
4469                 reverse_bd_addr(&packet[3], addr);
4470                 hci_stack->link_key_db->delete_link_key(addr);
4471             }
4472             break;
4473         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4474         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4475             reverse_bd_addr(&packet[3], addr);
4476             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4477             if (conn) {
4478                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4479             }
4480             break;
4481         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4482         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4483         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4484         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4485             reverse_bd_addr(&packet[3], addr);
4486             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4487             if (conn) {
4488                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4489             }
4490             break;
4491 
4492 #ifdef ENABLE_SCO_OVER_HCI
4493         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4494             // setup_synchronous_connection? Voice setting at offset 22
4495             // TODO: compare to current setting if sco connection already active
4496             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4497             break;
4498         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4499             // accept_synchronus_connection? Voice setting at offset 18
4500             // TODO: compare to current setting if sco connection already active
4501             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4502             break;
4503 #endif
4504 #endif
4505 
4506 #ifdef ENABLE_BLE
4507         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4508             hci_stack->le_random_address_set = 1;
4509             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4510             break;
4511 #ifdef ENABLE_LE_PERIPHERAL
4512         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4513             hci_stack->le_advertisements_active = packet[3] != 0;
4514             break;
4515 #endif
4516 #ifdef ENABLE_LE_CENTRAL
4517         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4518             // white list used?
4519             initiator_filter_policy = packet[7];
4520             switch (initiator_filter_policy) {
4521                 case 0:
4522                     // whitelist not used
4523                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4524                     break;
4525                 case 1:
4526                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4527                     break;
4528                 default:
4529                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4530                     break;
4531             }
4532             // track outgoing connection
4533             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4534             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4535             break;
4536         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4537             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4538             break;
4539 #endif
4540 #endif
4541         default:
4542             break;
4543     }
4544 
4545     hci_stack->num_cmd_packets--;
4546 
4547     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4548     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4549 }
4550 
4551 // disconnect because of security block
4552 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4553     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4554     if (!connection) return;
4555     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4556 }
4557 
4558 
4559 // Configure Secure Simple Pairing
4560 
4561 #ifdef ENABLE_CLASSIC
4562 
4563 // enable will enable SSP during init
4564 void gap_ssp_set_enable(int enable){
4565     hci_stack->ssp_enable = enable;
4566 }
4567 
4568 static int hci_local_ssp_activated(void){
4569     return gap_ssp_supported() && hci_stack->ssp_enable;
4570 }
4571 
4572 // if set, BTstack will respond to io capability request using authentication requirement
4573 void gap_ssp_set_io_capability(int io_capability){
4574     hci_stack->ssp_io_capability = io_capability;
4575 }
4576 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4577     hci_stack->ssp_authentication_requirement = authentication_requirement;
4578 }
4579 
4580 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4581 void gap_ssp_set_auto_accept(int auto_accept){
4582     hci_stack->ssp_auto_accept = auto_accept;
4583 }
4584 
4585 void gap_secure_connections_enable(bool enable){
4586     hci_stack->secure_connections_enable = enable;
4587 }
4588 
4589 #endif
4590 
4591 // va_list part of hci_send_cmd
4592 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4593     if (!hci_can_send_command_packet_now()){
4594         log_error("hci_send_cmd called but cannot send packet now");
4595         return 0;
4596     }
4597 
4598     // for HCI INITIALIZATION
4599     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4600     hci_stack->last_cmd_opcode = cmd->opcode;
4601 
4602     hci_reserve_packet_buffer();
4603     uint8_t * packet = hci_stack->hci_packet_buffer;
4604     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4605     int err = hci_send_cmd_packet(packet, size);
4606 
4607     // release packet buffer on error or for synchronous transport implementations
4608     if ((err < 0) || hci_transport_synchronous()){
4609         hci_release_packet_buffer();
4610         hci_emit_transport_packet_sent();
4611     }
4612 
4613     return err;
4614 }
4615 
4616 /**
4617  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4618  */
4619 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4620     va_list argptr;
4621     va_start(argptr, cmd);
4622     int res = hci_send_cmd_va_arg(cmd, argptr);
4623     va_end(argptr);
4624     return res;
4625 }
4626 
4627 // Create various non-HCI events.
4628 // TODO: generalize, use table similar to hci_create_command
4629 
4630 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4631     // dump packet
4632     if (dump) {
4633         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4634     }
4635 
4636     // dispatch to all event handlers
4637     btstack_linked_list_iterator_t it;
4638     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4639     while (btstack_linked_list_iterator_has_next(&it)){
4640         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4641         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4642     }
4643 }
4644 
4645 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4646     if (!hci_stack->acl_packet_handler) return;
4647     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4648 }
4649 
4650 #ifdef ENABLE_CLASSIC
4651 static void hci_notify_if_sco_can_send_now(void){
4652     // notify SCO sender if waiting
4653     if (!hci_stack->sco_waiting_for_can_send_now) return;
4654     if (hci_can_send_sco_packet_now()){
4655         hci_stack->sco_waiting_for_can_send_now = 0;
4656         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4657         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4658         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4659     }
4660 }
4661 
4662 // parsing end emitting has been merged to reduce code size
4663 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4664     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4665 
4666     uint8_t * eir_data;
4667     ad_context_t context;
4668     const uint8_t * name;
4669     uint8_t         name_len;
4670 
4671     if (size < 3) return;
4672 
4673     int event_type = hci_event_packet_get_type(packet);
4674     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4675     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4676 
4677     switch (event_type){
4678         case HCI_EVENT_INQUIRY_RESULT:
4679         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4680             if (size != (3 + (num_responses * 14))) return;
4681             break;
4682         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4683             if (size != 257) return;
4684             if (num_responses != 1) return;
4685             break;
4686         default:
4687             return;
4688     }
4689 
4690     // event[1] is set at the end
4691     int i;
4692     for (i=0; i<num_responses;i++){
4693         memset(event, 0, sizeof(event));
4694         event[0] = GAP_EVENT_INQUIRY_RESULT;
4695         uint8_t event_size = 18;    // if name is not set by EIR
4696 
4697         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4698         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4699         (void)memcpy(&event[9],
4700                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4701                      3); // class of device
4702         (void)memcpy(&event[12],
4703                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4704                      2); // clock offset
4705 
4706         switch (event_type){
4707             case HCI_EVENT_INQUIRY_RESULT:
4708                 // 14,15,16,17 = 0, size 18
4709                 break;
4710             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4711                 event[14] = 1;
4712                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4713                 // 16,17 = 0, size 18
4714                 break;
4715             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4716                 event[14] = 1;
4717                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4718                 // EIR packets only contain a single inquiry response
4719                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4720                 name = NULL;
4721                 // Iterate over EIR data
4722                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4723                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4724                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4725                     const uint8_t * data = ad_iterator_get_data(&context);
4726                     // Prefer Complete Local Name over Shortend Local Name
4727                     switch (data_type){
4728                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4729                             if (name) continue;
4730                             /* fall through */
4731                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4732                             name = data;
4733                             name_len = data_size;
4734                             break;
4735                         default:
4736                             break;
4737                     }
4738                 }
4739                 if (name){
4740                     event[16] = 1;
4741                     // truncate name if needed
4742                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4743                     event[17] = len;
4744                     (void)memcpy(&event[18], name, len);
4745                     event_size += len;
4746                 }
4747                 break;
4748         }
4749         event[1] = event_size - 2;
4750         hci_emit_event(event, event_size, 1);
4751     }
4752 }
4753 #endif
4754 
4755 void hci_emit_state(void){
4756     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4757     uint8_t event[3];
4758     event[0] = BTSTACK_EVENT_STATE;
4759     event[1] = sizeof(event) - 2u;
4760     event[2] = hci_stack->state;
4761     hci_emit_event(event, sizeof(event), 1);
4762 }
4763 
4764 #ifdef ENABLE_CLASSIC
4765 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4766     uint8_t event[13];
4767     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4768     event[1] = sizeof(event) - 2;
4769     event[2] = status;
4770     little_endian_store_16(event, 3, con_handle);
4771     reverse_bd_addr(address, &event[5]);
4772     event[11] = 1; // ACL connection
4773     event[12] = 0; // encryption disabled
4774     hci_emit_event(event, sizeof(event), 1);
4775 }
4776 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4777     if (disable_l2cap_timeouts) return;
4778     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4779     uint8_t event[4];
4780     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4781     event[1] = sizeof(event) - 2;
4782     little_endian_store_16(event, 2, conn->con_handle);
4783     hci_emit_event(event, sizeof(event), 1);
4784 }
4785 #endif
4786 
4787 #ifdef ENABLE_BLE
4788 #ifdef ENABLE_LE_CENTRAL
4789 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){
4790     uint8_t event[21];
4791     event[0] = HCI_EVENT_LE_META;
4792     event[1] = sizeof(event) - 2u;
4793     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4794     event[3] = status;
4795     little_endian_store_16(event, 4, con_handle);
4796     event[6] = 0; // TODO: role
4797     event[7] = address_type;
4798     reverse_bd_addr(address, &event[8]);
4799     little_endian_store_16(event, 14, 0); // interval
4800     little_endian_store_16(event, 16, 0); // latency
4801     little_endian_store_16(event, 18, 0); // supervision timeout
4802     event[20] = 0; // master clock accuracy
4803     hci_emit_event(event, sizeof(event), 1);
4804 }
4805 #endif
4806 #endif
4807 
4808 static void hci_emit_transport_packet_sent(void){
4809     // notify upper stack that it might be possible to send again
4810     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4811     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4812 }
4813 
4814 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4815     uint8_t event[6];
4816     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4817     event[1] = sizeof(event) - 2u;
4818     event[2] = 0; // status = OK
4819     little_endian_store_16(event, 3, con_handle);
4820     event[5] = reason;
4821     hci_emit_event(event, sizeof(event), 1);
4822 }
4823 
4824 static void hci_emit_nr_connections_changed(void){
4825     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4826     uint8_t event[3];
4827     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4828     event[1] = sizeof(event) - 2u;
4829     event[2] = nr_hci_connections();
4830     hci_emit_event(event, sizeof(event), 1);
4831 }
4832 
4833 static void hci_emit_hci_open_failed(void){
4834     log_info("BTSTACK_EVENT_POWERON_FAILED");
4835     uint8_t event[2];
4836     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4837     event[1] = sizeof(event) - 2u;
4838     hci_emit_event(event, sizeof(event), 1);
4839 }
4840 
4841 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4842     log_info("hci_emit_dedicated_bonding_result %u ", status);
4843     uint8_t event[9];
4844     int pos = 0;
4845     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4846     event[pos++] = sizeof(event) - 2u;
4847     event[pos++] = status;
4848     reverse_bd_addr(address, &event[pos]);
4849     hci_emit_event(event, sizeof(event), 1);
4850 }
4851 
4852 
4853 #ifdef ENABLE_CLASSIC
4854 
4855 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4856     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4857     uint8_t event[5];
4858     int pos = 0;
4859     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4860     event[pos++] = sizeof(event) - 2;
4861     little_endian_store_16(event, 2, con_handle);
4862     pos += 2;
4863     event[pos++] = level;
4864     hci_emit_event(event, sizeof(event), 1);
4865 }
4866 
4867 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4868     if (!connection) return LEVEL_0;
4869     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4870     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4871     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4872     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4873     // LEVEL 4 always requires 128 bit encrytion key size
4874     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4875         security_level = LEVEL_3;
4876     }
4877     return security_level;
4878 }
4879 
4880 static void hci_emit_discoverable_enabled(uint8_t enabled){
4881     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4882     uint8_t event[3];
4883     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4884     event[1] = sizeof(event) - 2;
4885     event[2] = enabled;
4886     hci_emit_event(event, sizeof(event), 1);
4887 }
4888 
4889 // query if remote side supports eSCO
4890 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4891     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4892     if (!connection) return 0;
4893     return (connection->remote_supported_features[0] & 1) != 0;
4894 }
4895 
4896 static bool hci_ssp_supported(hci_connection_t * connection){
4897     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4898     return (connection->bonding_flags & mask) == mask;
4899 }
4900 
4901 // query if remote side supports SSP
4902 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4903     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4904     if (!connection) return 0;
4905     return hci_ssp_supported(connection) ? 1 : 0;
4906 }
4907 
4908 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4909     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4910 }
4911 
4912 // GAP API
4913 /**
4914  * @bbrief enable/disable bonding. default is enabled
4915  * @praram enabled
4916  */
4917 void gap_set_bondable_mode(int enable){
4918     hci_stack->bondable = enable ? 1 : 0;
4919 }
4920 /**
4921  * @brief Get bondable mode.
4922  * @return 1 if bondable
4923  */
4924 int gap_get_bondable_mode(void){
4925     return hci_stack->bondable;
4926 }
4927 
4928 /**
4929  * @brief map link keys to security levels
4930  */
4931 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4932     switch (link_key_type){
4933         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4934             return LEVEL_4;
4935         case COMBINATION_KEY:
4936         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4937             return LEVEL_3;
4938         default:
4939             return LEVEL_2;
4940     }
4941 }
4942 
4943 /**
4944  * @brief map link keys to secure connection yes/no
4945  */
4946 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4947     switch (link_key_type){
4948         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4949         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4950             return 1;
4951         default:
4952             return 0;
4953     }
4954 }
4955 
4956 /**
4957  * @brief map link keys to authenticated
4958  */
4959 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4960     switch (link_key_type){
4961         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4962         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4963             return 1;
4964         default:
4965             return 0;
4966     }
4967 }
4968 
4969 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4970     log_info("gap_mitm_protection_required_for_security_level %u", level);
4971     return level > LEVEL_2;
4972 }
4973 
4974 /**
4975  * @brief get current security level
4976  */
4977 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4978     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4979     if (!connection) return LEVEL_0;
4980     return gap_security_level_for_connection(connection);
4981 }
4982 
4983 /**
4984  * @brief request connection to device to
4985  * @result GAP_AUTHENTICATION_RESULT
4986  */
4987 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4988     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4989     if (!connection){
4990         hci_emit_security_level(con_handle, LEVEL_0);
4991         return;
4992     }
4993     gap_security_level_t current_level = gap_security_level(con_handle);
4994     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4995         requested_level, connection->requested_security_level, current_level);
4996 
4997     // assumption: earlier requested security higher than current level => security request is active
4998     if (current_level < connection->requested_security_level){
4999         if (connection->requested_security_level < requested_level){
5000             // increase requested level as new level is higher
5001 
5002             // TODO: handle re-authentication when done
5003 
5004             connection->requested_security_level = requested_level;
5005         }
5006         return;
5007     }
5008 
5009     // no request active, notify if security sufficient
5010     if (requested_level <= current_level){
5011         hci_emit_security_level(con_handle, current_level);
5012         return;
5013     }
5014 
5015     // start pairing to increase security level
5016     connection->requested_security_level = requested_level;
5017 
5018 #if 0
5019     // sending encryption request without a link key results in an error.
5020     // TODO: figure out how to use it properly
5021 
5022     // would enabling ecnryption suffice (>= LEVEL_2)?
5023     if (hci_stack->link_key_db){
5024         link_key_type_t link_key_type;
5025         link_key_t      link_key;
5026         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
5027             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
5028                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
5029                 return;
5030             }
5031         }
5032     }
5033 #endif
5034 
5035     // start to authenticate connection if not already active
5036     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
5037     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5038     hci_run();
5039 }
5040 
5041 /**
5042  * @brief start dedicated bonding with device. disconnect after bonding
5043  * @param device
5044  * @param request MITM protection
5045  * @result GAP_DEDICATED_BONDING_COMPLETE
5046  */
5047 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5048 
5049     // create connection state machine
5050     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5051 
5052     if (!connection){
5053         return BTSTACK_MEMORY_ALLOC_FAILED;
5054     }
5055 
5056     // delete linkn key
5057     gap_drop_link_key_for_bd_addr(device);
5058 
5059     // configure LEVEL_2/3, dedicated bonding
5060     connection->state = SEND_CREATE_CONNECTION;
5061     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5062     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5063     connection->bonding_flags = BONDING_DEDICATED;
5064 
5065     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5066 
5067     // handle: connnection failure (connection complete != ok)
5068     // handle: authentication failure
5069     // handle: disconnect on done
5070 
5071     hci_run();
5072 
5073     return 0;
5074 }
5075 #endif
5076 
5077 void gap_set_local_name(const char * local_name){
5078     hci_stack->local_name = local_name;
5079 }
5080 
5081 
5082 #ifdef ENABLE_BLE
5083 
5084 #ifdef ENABLE_LE_CENTRAL
5085 void gap_start_scan(void){
5086     hci_stack->le_scanning_enabled = true;
5087     hci_run();
5088 }
5089 
5090 void gap_stop_scan(void){
5091     hci_stack->le_scanning_enabled = false;
5092     hci_run();
5093 }
5094 
5095 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5096     hci_stack->le_scan_type          = scan_type;
5097     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5098     hci_stack->le_scan_interval      = scan_interval;
5099     hci_stack->le_scan_window        = scan_window;
5100     hci_stack->le_scanning_param_update = true;
5101     hci_run();
5102 }
5103 
5104 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5105     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5106 }
5107 
5108 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5109     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5110     if (!conn){
5111         // disallow if le connection is already outgoing
5112         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5113             log_error("le connection already active");
5114             return ERROR_CODE_COMMAND_DISALLOWED;
5115         }
5116 
5117         log_info("gap_connect: no connection exists yet, creating context");
5118         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5119         if (!conn){
5120             // notify client that alloc failed
5121             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5122             log_info("gap_connect: failed to alloc hci_connection_t");
5123             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5124         }
5125 
5126         // set le connecting state
5127         if (hci_is_le_connection_type(addr_type)){
5128             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5129         }
5130 
5131         conn->state = SEND_CREATE_CONNECTION;
5132         log_info("gap_connect: send create connection next");
5133         hci_run();
5134         return ERROR_CODE_SUCCESS;
5135     }
5136 
5137     if (!hci_is_le_connection(conn) ||
5138         (conn->state == SEND_CREATE_CONNECTION) ||
5139         (conn->state == SENT_CREATE_CONNECTION)) {
5140         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5141         log_error("gap_connect: classic connection or connect is already being created");
5142         return GATT_CLIENT_IN_WRONG_STATE;
5143     }
5144 
5145     // check if connection was just disconnected
5146     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5147         log_info("gap_connect: send create connection (again)");
5148         conn->state = SEND_CREATE_CONNECTION;
5149         hci_run();
5150         return ERROR_CODE_SUCCESS;
5151     }
5152 
5153     log_info("gap_connect: context exists with state %u", conn->state);
5154     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5155     hci_run();
5156     return ERROR_CODE_SUCCESS;
5157 }
5158 
5159 // @assumption: only a single outgoing LE Connection exists
5160 static hci_connection_t * gap_get_outgoing_connection(void){
5161     btstack_linked_item_t *it;
5162     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5163         hci_connection_t * conn = (hci_connection_t *) it;
5164         if (!hci_is_le_connection(conn)) continue;
5165         switch (conn->state){
5166             case SEND_CREATE_CONNECTION:
5167             case SENT_CREATE_CONNECTION:
5168             case SENT_CANCEL_CONNECTION:
5169                 return conn;
5170             default:
5171                 break;
5172         };
5173     }
5174     return NULL;
5175 }
5176 
5177 uint8_t gap_connect_cancel(void){
5178     hci_connection_t * conn = gap_get_outgoing_connection();
5179     if (!conn) return 0;
5180     switch (conn->state){
5181         case SEND_CREATE_CONNECTION:
5182             // skip sending create connection and emit event instead
5183             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5184             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5185             btstack_memory_hci_connection_free( conn );
5186             break;
5187         case SENT_CREATE_CONNECTION:
5188             // request to send cancel connection
5189             conn->state = SEND_CANCEL_CONNECTION;
5190             hci_run();
5191             break;
5192         default:
5193             break;
5194     }
5195     return 0;
5196 }
5197 #endif
5198 
5199 #ifdef ENABLE_LE_CENTRAL
5200 /**
5201  * @brief Set connection parameters for outgoing connections
5202  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5203  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5204  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5205  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5206  * @param conn_latency, default: 4
5207  * @param supervision_timeout (unit: 10ms), default: 720 ms
5208  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5209  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5210  */
5211 
5212 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5213     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5214     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5215     hci_stack->le_connection_scan_interval = conn_scan_interval;
5216     hci_stack->le_connection_scan_window = conn_scan_window;
5217     hci_stack->le_connection_interval_min = conn_interval_min;
5218     hci_stack->le_connection_interval_max = conn_interval_max;
5219     hci_stack->le_connection_latency = conn_latency;
5220     hci_stack->le_supervision_timeout = supervision_timeout;
5221     hci_stack->le_minimum_ce_length = min_ce_length;
5222     hci_stack->le_maximum_ce_length = max_ce_length;
5223 }
5224 #endif
5225 
5226 /**
5227  * @brief Updates the connection parameters for a given LE connection
5228  * @param handle
5229  * @param conn_interval_min (unit: 1.25ms)
5230  * @param conn_interval_max (unit: 1.25ms)
5231  * @param conn_latency
5232  * @param supervision_timeout (unit: 10ms)
5233  * @returns 0 if ok
5234  */
5235 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5236     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5237     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5238     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5239     connection->le_conn_interval_min = conn_interval_min;
5240     connection->le_conn_interval_max = conn_interval_max;
5241     connection->le_conn_latency = conn_latency;
5242     connection->le_supervision_timeout = supervision_timeout;
5243     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5244     hci_run();
5245     return 0;
5246 }
5247 
5248 /**
5249  * @brief Request an update of the connection parameter for a given LE connection
5250  * @param handle
5251  * @param conn_interval_min (unit: 1.25ms)
5252  * @param conn_interval_max (unit: 1.25ms)
5253  * @param conn_latency
5254  * @param supervision_timeout (unit: 10ms)
5255  * @returns 0 if ok
5256  */
5257 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5258     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5259     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5260     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5261     connection->le_conn_interval_min = conn_interval_min;
5262     connection->le_conn_interval_max = conn_interval_max;
5263     connection->le_conn_latency = conn_latency;
5264     connection->le_supervision_timeout = supervision_timeout;
5265     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5266     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5267     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5268     return 0;
5269 }
5270 
5271 #ifdef ENABLE_LE_PERIPHERAL
5272 
5273 /**
5274  * @brief Set Advertisement Data
5275  * @param advertising_data_length
5276  * @param advertising_data (max 31 octets)
5277  * @note data is not copied, pointer has to stay valid
5278  */
5279 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5280     hci_stack->le_advertisements_data_len = advertising_data_length;
5281     hci_stack->le_advertisements_data = advertising_data;
5282     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5283     hci_run();
5284 }
5285 
5286 /**
5287  * @brief Set Scan Response Data
5288  * @param advertising_data_length
5289  * @param advertising_data (max 31 octets)
5290  * @note data is not copied, pointer has to stay valid
5291  */
5292 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5293     hci_stack->le_scan_response_data_len = scan_response_data_length;
5294     hci_stack->le_scan_response_data = scan_response_data;
5295     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5296     hci_run();
5297 }
5298 
5299 /**
5300  * @brief Set Advertisement Parameters
5301  * @param adv_int_min
5302  * @param adv_int_max
5303  * @param adv_type
5304  * @param direct_address_type
5305  * @param direct_address
5306  * @param channel_map
5307  * @param filter_policy
5308  *
5309  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5310  */
5311  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5312     uint8_t direct_address_typ, bd_addr_t direct_address,
5313     uint8_t channel_map, uint8_t filter_policy) {
5314 
5315     hci_stack->le_advertisements_interval_min = adv_int_min;
5316     hci_stack->le_advertisements_interval_max = adv_int_max;
5317     hci_stack->le_advertisements_type = adv_type;
5318     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5319     hci_stack->le_advertisements_channel_map = channel_map;
5320     hci_stack->le_advertisements_filter_policy = filter_policy;
5321     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5322                  6);
5323 
5324     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5325     hci_run();
5326  }
5327 
5328 /**
5329  * @brief Enable/Disable Advertisements
5330  * @param enabled
5331  */
5332 void gap_advertisements_enable(int enabled){
5333     hci_stack->le_advertisements_enabled = enabled != 0;
5334     hci_update_advertisements_enabled_for_current_roles();
5335     hci_run();
5336 }
5337 
5338 #endif
5339 
5340 void hci_le_set_own_address_type(uint8_t own_address_type){
5341     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5342     if (own_address_type == hci_stack->le_own_addr_type) return;
5343     hci_stack->le_own_addr_type = own_address_type;
5344 
5345 #ifdef ENABLE_LE_PERIPHERAL
5346     // update advertisement parameters, too
5347     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5348     hci_run();
5349 #endif
5350 #ifdef ENABLE_LE_CENTRAL
5351     // note: we don't update scan parameters or modify ongoing connection attempts
5352 #endif
5353 }
5354 
5355 #endif
5356 
5357 uint8_t gap_disconnect(hci_con_handle_t handle){
5358     hci_connection_t * conn = hci_connection_for_handle(handle);
5359     if (!conn){
5360         hci_emit_disconnection_complete(handle, 0);
5361         return 0;
5362     }
5363     // ignore if already disconnected
5364     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5365         return 0;
5366     }
5367     conn->state = SEND_DISCONNECT;
5368     hci_run();
5369     return 0;
5370 }
5371 
5372 int gap_read_rssi(hci_con_handle_t con_handle){
5373     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5374     if (hci_connection == NULL) return 0;
5375     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5376     hci_run();
5377     return 1;
5378 }
5379 
5380 /**
5381  * @brief Get connection type
5382  * @param con_handle
5383  * @result connection_type
5384  */
5385 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5386     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5387     if (!conn) return GAP_CONNECTION_INVALID;
5388     switch (conn->address_type){
5389         case BD_ADDR_TYPE_LE_PUBLIC:
5390         case BD_ADDR_TYPE_LE_RANDOM:
5391             return GAP_CONNECTION_LE;
5392         case BD_ADDR_TYPE_SCO:
5393             return GAP_CONNECTION_SCO;
5394         case BD_ADDR_TYPE_ACL:
5395             return GAP_CONNECTION_ACL;
5396         default:
5397             return GAP_CONNECTION_INVALID;
5398     }
5399 }
5400 
5401 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5402     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5403     if (!conn) return HCI_ROLE_INVALID;
5404     return (hci_role_t) conn->role;
5405 }
5406 
5407 
5408 #ifdef ENABLE_CLASSIC
5409 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5410     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5411     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5412     conn->request_role = role;
5413     hci_run();
5414     return ERROR_CODE_SUCCESS;
5415 }
5416 #endif
5417 
5418 #ifdef ENABLE_BLE
5419 
5420 uint8_t gap_le_set_phy(hci_con_handle_t connection_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
5421     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5422     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5423 
5424     conn->le_phy_update_all_phys    = all_phys;
5425     conn->le_phy_update_tx_phys     = tx_phys;
5426     conn->le_phy_update_rx_phys     = rx_phys;
5427     conn->le_phy_update_phy_options = phy_options;
5428 
5429     hci_run();
5430 
5431     return 0;
5432 }
5433 
5434 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5435     // check if already in list
5436     btstack_linked_list_iterator_t it;
5437     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5438     while (btstack_linked_list_iterator_has_next(&it)) {
5439         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5440         if (entry->address_type != address_type) {
5441             continue;
5442         }
5443         if (memcmp(entry->address, address, 6) != 0) {
5444             continue;
5445         }
5446         // already in there
5447         return ERROR_CODE_COMMAND_DISALLOWED;
5448     }
5449     // alloc and add to list
5450     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5451     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5452     entry->address_type = address_type;
5453     (void)memcpy(entry->address, address, 6);
5454     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5455     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5456     return ERROR_CODE_SUCCESS;
5457 }
5458 
5459 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5460     btstack_linked_list_iterator_t it;
5461     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5462     while (btstack_linked_list_iterator_has_next(&it)){
5463         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5464         if (entry->address_type != address_type) {
5465             continue;
5466         }
5467         if (memcmp(entry->address, address, 6) != 0) {
5468             continue;
5469         }
5470         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5471             // remove from controller if already present
5472             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5473         }  else {
5474             // directly remove entry from whitelist
5475             btstack_linked_list_iterator_remove(&it);
5476             btstack_memory_whitelist_entry_free(entry);
5477         }
5478         return ERROR_CODE_SUCCESS;
5479     }
5480     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5481 }
5482 
5483 static void hci_whitelist_clear(void){
5484     btstack_linked_list_iterator_t it;
5485     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5486     while (btstack_linked_list_iterator_has_next(&it)){
5487         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5488         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5489             // remove from controller if already present
5490             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5491             continue;
5492         }
5493         // directly remove entry from whitelist
5494         btstack_linked_list_iterator_remove(&it);
5495         btstack_memory_whitelist_entry_free(entry);
5496     }
5497 }
5498 
5499 /**
5500  * @brief Clear Whitelist
5501  * @returns 0 if ok
5502  */
5503 uint8_t gap_whitelist_clear(void){
5504     hci_whitelist_clear();
5505     hci_run();
5506     return ERROR_CODE_SUCCESS;
5507 }
5508 
5509 /**
5510  * @brief Add Device to Whitelist
5511  * @param address_typ
5512  * @param address
5513  * @returns 0 if ok
5514  */
5515 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5516     uint8_t status = hci_whitelist_add(address_type, address);
5517     if (status){
5518         return status;
5519     }
5520     hci_run();
5521     return ERROR_CODE_SUCCESS;
5522 }
5523 
5524 /**
5525  * @brief Remove Device from Whitelist
5526  * @param address_typ
5527  * @param address
5528  * @returns 0 if ok
5529  */
5530 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5531     uint8_t status = hci_whitelist_remove(address_type, address);
5532     if (status){
5533         return status;
5534     }
5535     hci_run();
5536     return ERROR_CODE_SUCCESS;
5537 }
5538 
5539 #ifdef ENABLE_LE_CENTRAL
5540 /**
5541  *  @brief Connect with Whitelist
5542  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5543  *  @returns - if ok
5544  */
5545 uint8_t gap_connect_with_whitelist(void){
5546     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5547         return ERROR_CODE_COMMAND_DISALLOWED;
5548     }
5549     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5550     hci_run();
5551     return ERROR_CODE_SUCCESS;
5552 }
5553 
5554 /**
5555  * @brief Auto Connection Establishment - Start Connecting to device
5556  * @param address_typ
5557  * @param address
5558  * @returns 0 if ok
5559  */
5560 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
5561     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5562         return ERROR_CODE_COMMAND_DISALLOWED;
5563     }
5564 
5565     uint8_t status = hci_whitelist_add(address_type, address);
5566     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5567         return status;
5568     }
5569 
5570     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5571 
5572     hci_run();
5573     return ERROR_CODE_SUCCESS;
5574 }
5575 
5576 /**
5577  * @brief Auto Connection Establishment - Stop Connecting to device
5578  * @param address_typ
5579  * @param address
5580  * @returns 0 if ok
5581  */
5582 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
5583     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5584         return ERROR_CODE_COMMAND_DISALLOWED;
5585     }
5586 
5587     hci_whitelist_remove(address_type, address);
5588     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5589         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5590     }
5591     hci_run();
5592     return 0;
5593 }
5594 
5595 /**
5596  * @brief Auto Connection Establishment - Stop everything
5597  * @note  Convenience function to stop all active auto connection attempts
5598  */
5599 uint8_t gap_auto_connection_stop_all(void){
5600     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5601         return ERROR_CODE_COMMAND_DISALLOWED;
5602     }
5603     hci_whitelist_clear();
5604     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5605     hci_run();
5606     return ERROR_CODE_SUCCESS;
5607 }
5608 
5609 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5610     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5611     if (!conn) return 0;
5612     return conn->le_connection_interval;
5613 }
5614 #endif
5615 #endif
5616 
5617 #ifdef ENABLE_CLASSIC
5618 /**
5619  * @brief Set Extended Inquiry Response data
5620  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5621  * @note has to be done before stack starts up
5622  */
5623 void gap_set_extended_inquiry_response(const uint8_t * data){
5624     hci_stack->eir_data = data;
5625 }
5626 
5627 /**
5628  * @brief Start GAP Classic Inquiry
5629  * @param duration in 1.28s units
5630  * @return 0 if ok
5631  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5632  */
5633 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5634     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5635     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5636     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5637         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5638     }
5639     hci_stack->inquiry_state = duration_in_1280ms_units;
5640     hci_run();
5641     return 0;
5642 }
5643 
5644 /**
5645  * @brief Stop GAP Classic Inquiry
5646  * @returns 0 if ok
5647  */
5648 int gap_inquiry_stop(void){
5649     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5650         // emit inquiry complete event, before it even started
5651         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5652         hci_emit_event(event, sizeof(event), 1);
5653         return 0;
5654     }
5655     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5656     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5657     hci_run();
5658     return 0;
5659 }
5660 
5661 
5662 /**
5663  * @brief Remote Name Request
5664  * @param addr
5665  * @param page_scan_repetition_mode
5666  * @param clock_offset only used when bit 15 is set
5667  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5668  */
5669 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5670     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5671     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5672     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5673     hci_stack->remote_name_clock_offset = clock_offset;
5674     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5675     hci_run();
5676     return 0;
5677 }
5678 
5679 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
5680     hci_stack->gap_pairing_state = state;
5681     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5682     hci_run();
5683     return 0;
5684 }
5685 
5686 /**
5687  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5688  * @param addr
5689  * @param pin_data
5690  * @param pin_len
5691  * @return 0 if ok
5692  */
5693 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5694     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5695     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5696     hci_stack->gap_pairing_pin_len = pin_len;
5697     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5698 }
5699 
5700 /**
5701  * @brief Legacy Pairing Pin Code Response
5702  * @param addr
5703  * @param pin
5704  * @return 0 if ok
5705  */
5706 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
5707     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5708 }
5709 
5710 /**
5711  * @brief Abort Legacy Pairing
5712  * @param addr
5713  * @param pin
5714  * @return 0 if ok
5715  */
5716 int gap_pin_code_negative(bd_addr_t addr){
5717     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5718     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5719 }
5720 
5721 /**
5722  * @brief SSP Passkey Response
5723  * @param addr
5724  * @param passkey
5725  * @return 0 if ok
5726  */
5727 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
5728     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5729     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5730     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5731 }
5732 
5733 /**
5734  * @brief Abort SSP Passkey Entry/Pairing
5735  * @param addr
5736  * @param pin
5737  * @return 0 if ok
5738  */
5739 int gap_ssp_passkey_negative(const bd_addr_t addr){
5740     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5741     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5742 }
5743 
5744 /**
5745  * @brief Accept SSP Numeric Comparison
5746  * @param addr
5747  * @param passkey
5748  * @return 0 if ok
5749  */
5750 int gap_ssp_confirmation_response(const bd_addr_t addr){
5751     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5752     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5753 }
5754 
5755 /**
5756  * @brief Abort SSP Numeric Comparison/Pairing
5757  * @param addr
5758  * @param pin
5759  * @return 0 if ok
5760  */
5761 int gap_ssp_confirmation_negative(const bd_addr_t addr){
5762     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5763     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5764 }
5765 
5766 /**
5767  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5768  * @param inquiry_mode see bluetooth_defines.h
5769  */
5770 void hci_set_inquiry_mode(inquiry_mode_t mode){
5771     hci_stack->inquiry_mode = mode;
5772 }
5773 
5774 /**
5775  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5776  */
5777 void hci_set_sco_voice_setting(uint16_t voice_setting){
5778     hci_stack->sco_voice_setting = voice_setting;
5779 }
5780 
5781 /**
5782  * @brief Get SCO Voice Setting
5783  * @return current voice setting
5784  */
5785 uint16_t hci_get_sco_voice_setting(void){
5786     return hci_stack->sco_voice_setting;
5787 }
5788 
5789 static int hci_have_usb_transport(void){
5790     if (!hci_stack->hci_transport) return 0;
5791     const char * transport_name = hci_stack->hci_transport->name;
5792     if (!transport_name) return 0;
5793     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5794 }
5795 
5796 /** @brief Get SCO packet length for current SCO Voice setting
5797  *  @note  Using SCO packets of the exact length is required for USB transfer
5798  *  @return Length of SCO packets in bytes (not audio frames)
5799  */
5800 int hci_get_sco_packet_length(void){
5801     int sco_packet_length = 0;
5802 
5803 #ifdef ENABLE_SCO_OVER_HCI
5804 
5805     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5806     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5807 
5808     if (hci_have_usb_transport()){
5809         // see Core Spec for H2 USB Transfer.
5810         // 3 byte SCO header + 24 bytes per connection
5811         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5812         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5813     } else {
5814         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5815         sco_packet_length = 3 + 60 * multiplier;
5816         // assert that it still fits inside an SCO buffer
5817         if (sco_packet_length > hci_stack->sco_data_packet_length){
5818             sco_packet_length = 3 + 60;
5819         }
5820     }
5821 #endif
5822     return sco_packet_length;
5823 }
5824 
5825 /**
5826 * @brief Sets the master/slave policy
5827 * @param policy (0: attempt to become master, 1: let connecting device decide)
5828 */
5829 void hci_set_master_slave_policy(uint8_t policy){
5830     hci_stack->master_slave_policy = policy;
5831 }
5832 
5833 #endif
5834 
5835 HCI_STATE hci_get_state(void){
5836     return hci_stack->state;
5837 }
5838 
5839 #ifdef ENABLE_CLASSIC
5840 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5841     hci_stack->gap_classic_accept_callback = accept_callback;
5842 }
5843 #endif
5844 
5845 /**
5846  * @brief Set callback for Bluetooth Hardware Error
5847  */
5848 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5849     hci_stack->hardware_error_callback = fn;
5850 }
5851 
5852 void hci_disconnect_all(void){
5853     btstack_linked_list_iterator_t it;
5854     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5855     while (btstack_linked_list_iterator_has_next(&it)){
5856         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5857         if (con->state == SENT_DISCONNECT) continue;
5858         con->state = SEND_DISCONNECT;
5859     }
5860     hci_run();
5861 }
5862 
5863 uint16_t hci_get_manufacturer(void){
5864     return hci_stack->manufacturer;
5865 }
5866 
5867 #ifdef ENABLE_BLE
5868 
5869 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5870     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5871     if (!hci_con) return NULL;
5872     return &hci_con->sm_connection;
5873 }
5874 
5875 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5876 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5877 
5878 int gap_encryption_key_size(hci_con_handle_t con_handle){
5879     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5880     if (hci_connection == NULL) return 0;
5881     if (hci_is_le_connection(hci_connection)){
5882         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5883         if (sm_conn->sm_connection_encrypted) {
5884             return sm_conn->sm_actual_encryption_key_size;
5885         }
5886     }
5887 #ifdef ENABLE_CLASSIC
5888     else {
5889         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5890             return hci_connection->encryption_key_size;
5891         }
5892     }
5893 #endif
5894     return 0;
5895 }
5896 
5897 int gap_authenticated(hci_con_handle_t con_handle){
5898     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5899     if (hci_connection == NULL) return 0;
5900 
5901     switch (hci_connection->address_type){
5902         case BD_ADDR_TYPE_LE_PUBLIC:
5903         case BD_ADDR_TYPE_LE_RANDOM:
5904             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5905             return hci_connection->sm_connection.sm_connection_authenticated;
5906 #ifdef ENABLE_CLASSIC
5907         case BD_ADDR_TYPE_SCO:
5908         case BD_ADDR_TYPE_ACL:
5909             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5910 #endif
5911         default:
5912             return 0;
5913     }
5914 }
5915 
5916 int gap_secure_connection(hci_con_handle_t con_handle){
5917     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5918     if (hci_connection == NULL) return 0;
5919 
5920     switch (hci_connection->address_type){
5921         case BD_ADDR_TYPE_LE_PUBLIC:
5922         case BD_ADDR_TYPE_LE_RANDOM:
5923             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5924             return hci_connection->sm_connection.sm_connection_sc;
5925 #ifdef ENABLE_CLASSIC
5926         case BD_ADDR_TYPE_SCO:
5927         case BD_ADDR_TYPE_ACL:
5928             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5929 #endif
5930         default:
5931             return 0;
5932     }
5933 }
5934 
5935 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5936     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5937     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5938     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5939     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5940     return sm_conn->sm_connection_authorization_state;
5941 }
5942 #endif
5943 
5944 #ifdef ENABLE_CLASSIC
5945 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){
5946     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5947     if (!conn) return GAP_CONNECTION_INVALID;
5948     conn->sniff_min_interval = sniff_min_interval;
5949     conn->sniff_max_interval = sniff_max_interval;
5950     conn->sniff_attempt = sniff_attempt;
5951     conn->sniff_timeout = sniff_timeout;
5952     hci_run();
5953     return 0;
5954 }
5955 
5956 /**
5957  * @brief Exit Sniff mode
5958  * @param con_handle
5959  @ @return 0 if ok
5960  */
5961 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5962     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5963     if (!conn) return GAP_CONNECTION_INVALID;
5964     conn->sniff_min_interval = 0xffff;
5965     hci_run();
5966     return 0;
5967 }
5968 #endif
5969 
5970 void hci_halting_defer(void){
5971     if (hci_stack->state != HCI_STATE_HALTING) return;
5972     switch (hci_stack->substate){
5973         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5974         case HCI_HALTING_CLOSE:
5975             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5976             break;
5977         default:
5978             break;
5979     }
5980 }
5981 
5982 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
5983 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
5984     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
5985     if (le_device_db_index >= le_device_db_max_count()) return;
5986     uint8_t offset = le_device_db_index >> 3;
5987     uint8_t mask = 1 << (le_device_db_index & 7);
5988     hci_stack->le_resolving_list_add_entries[offset] |= mask;
5989     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
5990     	// note: go back to remove entries, otherwise, a remove + add will skip the add
5991         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
5992     }
5993 }
5994 
5995 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
5996 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
5997 	if (le_device_db_index >= le_device_db_max_count()) return;
5998 	uint8_t offset = le_device_db_index >> 3;
5999 	uint8_t mask = 1 << (le_device_db_index & 7);
6000 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6001 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6002 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6003 	}
6004 }
6005 
6006 uint8_t gap_load_resolving_list_from_le_device_db(void){
6007 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6008 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6009 	}
6010 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6011 		// restart le resolving list update
6012 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6013 	}
6014 	return ERROR_CODE_SUCCESS;
6015 }
6016 #endif
6017 
6018 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6019 void hci_setup_test_connections_fuzz(void){
6020     hci_connection_t * conn;
6021 
6022     // default address: 66:55:44:33:00:01
6023     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6024 
6025     // setup Controller info
6026     hci_stack->num_cmd_packets = 255;
6027     hci_stack->acl_packets_total_num = 255;
6028 
6029     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6030     addr[5] = 0x01;
6031     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6032     conn->con_handle = addr[5];
6033     conn->role  = HCI_ROLE_SLAVE;
6034     conn->state = RECEIVED_CONNECTION_REQUEST;
6035     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6036 
6037     // setup incoming Classic SCO connection with con handle 0x0002
6038     addr[5] = 0x02;
6039     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6040     conn->con_handle = addr[5];
6041     conn->role  = HCI_ROLE_SLAVE;
6042     conn->state = RECEIVED_CONNECTION_REQUEST;
6043     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6044 
6045     // setup ready Classic ACL connection with con handle 0x0003
6046     addr[5] = 0x03;
6047     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6048     conn->con_handle = addr[5];
6049     conn->role  = HCI_ROLE_SLAVE;
6050     conn->state = OPEN;
6051     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6052 
6053     // setup ready Classic SCO connection with con handle 0x0004
6054     addr[5] = 0x04;
6055     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6056     conn->con_handle = addr[5];
6057     conn->role  = HCI_ROLE_SLAVE;
6058     conn->state = OPEN;
6059     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6060 
6061     // setup ready LE ACL connection with con handle 0x005 and public address
6062     addr[5] = 0x05;
6063     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6064     conn->con_handle = addr[5];
6065     conn->role  = HCI_ROLE_SLAVE;
6066     conn->state = OPEN;
6067     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6068 }
6069 
6070 void hci_free_connections_fuzz(void){
6071     btstack_linked_list_iterator_t it;
6072     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6073     while (btstack_linked_list_iterator_has_next(&it)){
6074         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6075         btstack_linked_list_iterator_remove(&it);
6076         btstack_memory_hci_connection_free(con);
6077     }
6078 }
6079 void hci_simulate_working_fuzz(void){
6080     hci_init_done();
6081     hci_stack->num_cmd_packets = 255;
6082 }
6083 #endif
6084