xref: /btstack/src/hci.c (revision f400efd4c34c2c3d094122d9c99ddcc5357e2a2e)
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 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <inttypes.h>
67 
68 #include "btstack_debug.h"
69 #include "btstack_event.h"
70 #include "btstack_linked_list.h"
71 #include "btstack_memory.h"
72 #include "bluetooth_company_id.h"
73 #include "bluetooth_data_types.h"
74 #include "gap.h"
75 #include "hci.h"
76 #include "hci_cmd.h"
77 #include "hci_dump.h"
78 #include "ad_parser.h"
79 
80 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
81 #ifndef HCI_HOST_ACL_PACKET_NUM
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
83 #endif
84 #ifndef HCI_HOST_ACL_PACKET_LEN
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_NUM
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
89 #endif
90 #ifndef HCI_HOST_SCO_PACKET_LEN
91 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
92 #endif
93 #endif
94 
95 #define HCI_CONNECTION_TIMEOUT_MS 10000
96 
97 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
98 #define HCI_RESET_RESEND_TIMEOUT_MS 200
99 #endif
100 
101 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
102 #ifndef GAP_INQUIRY_MAX_NAME_LEN
103 #define GAP_INQUIRY_MAX_NAME_LEN 32
104 #endif
105 
106 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
107 #define GAP_INQUIRY_DURATION_MIN 0x01
108 #define GAP_INQUIRY_DURATION_MAX 0x30
109 #define GAP_INQUIRY_STATE_ACTIVE 0x80
110 #define GAP_INQUIRY_STATE_IDLE 0
111 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
112 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
113 
114 // GAP Remote Name Request
115 #define GAP_REMOTE_NAME_STATE_IDLE 0
116 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
117 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
118 
119 // GAP Pairing
120 #define GAP_PAIRING_STATE_IDLE                       0
121 #define GAP_PAIRING_STATE_SEND_PIN                   1
122 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
123 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
124 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
125 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
127 
128 
129 // prototypes
130 #ifdef ENABLE_CLASSIC
131 static void hci_update_scan_enable(void);
132 static void hci_emit_discoverable_enabled(uint8_t enabled);
133 static int  hci_local_ssp_activated(void);
134 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
135 static bool hci_ssp_supported(hci_connection_t * connection);
136 static void hci_notify_if_sco_can_send_now(void);
137 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
138 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
139 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
140 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
141 static void hci_connection_timestamp(hci_connection_t *connection);
142 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
143 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
144 #endif
145 
146 static int  hci_power_control_on(void);
147 static void hci_power_control_off(void);
148 static void hci_state_reset(void);
149 static void hci_emit_transport_packet_sent(void);
150 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
151 static void hci_emit_nr_connections_changed(void);
152 static void hci_emit_hci_open_failed(void);
153 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
154 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
155 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
156 static void hci_run(void);
157 static int  hci_is_le_connection(hci_connection_t * connection);
158 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
159 
160 #ifdef ENABLE_CLASSIC
161 static int hci_have_usb_transport(void);
162 #endif
163 
164 #ifdef ENABLE_BLE
165 #ifdef ENABLE_LE_CENTRAL
166 // called from test/ble_client/advertising_data_parser.c
167 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
168 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address);
169 static hci_connection_t * gap_get_outgoing_connection(void);
170 #endif
171 #endif
172 
173 // the STACK is here
174 #ifndef HAVE_MALLOC
175 static hci_stack_t   hci_stack_static;
176 #endif
177 static hci_stack_t * hci_stack = NULL;
178 
179 #ifdef ENABLE_CLASSIC
180 // default name
181 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
182 
183 // test helper
184 static uint8_t disable_l2cap_timeouts = 0;
185 #endif
186 
187 /**
188  * create connection for given address
189  *
190  * @return connection OR NULL, if no memory left
191  */
192 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
193     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
194     hci_connection_t * conn = btstack_memory_hci_connection_get();
195     if (!conn) return NULL;
196     bd_addr_copy(conn->address, addr);
197     conn->role = HCI_ROLE_INVALID;
198     conn->address_type = addr_type;
199     conn->con_handle = 0xffff;
200     conn->authentication_flags = AUTH_FLAGS_NONE;
201     conn->bonding_flags = 0;
202     conn->requested_security_level = LEVEL_0;
203 #ifdef ENABLE_CLASSIC
204     conn->request_role = HCI_ROLE_INVALID;
205     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
206     btstack_run_loop_set_timer_context(&conn->timeout, conn);
207     hci_connection_timestamp(conn);
208 #endif
209     conn->acl_recombination_length = 0;
210     conn->acl_recombination_pos = 0;
211     conn->num_packets_sent = 0;
212 
213     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
214 #ifdef ENABLE_BLE
215     conn->le_phy_update_all_phys = 0xff;
216 #endif
217 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
218     conn->le_max_tx_octets = 27;
219 #endif
220     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
221     return conn;
222 }
223 
224 
225 /**
226  * get le connection parameter range
227 *
228  * @return le connection parameter range struct
229  */
230 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
231     *range = hci_stack->le_connection_parameter_range;
232 }
233 
234 /**
235  * set le connection parameter range
236  *
237  */
238 
239 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
240     hci_stack->le_connection_parameter_range = *range;
241 }
242 
243 /**
244  * @brief Test if connection parameters are inside in existing rage
245  * @param conn_interval_min (unit: 1.25ms)
246  * @param conn_interval_max (unit: 1.25ms)
247  * @param conn_latency
248  * @param supervision_timeout (unit: 10ms)
249  * @returns 1 if included
250  */
251 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){
252     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
253     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
254 
255     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
256     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
257 
258     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
259     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
260 
261     return 1;
262 }
263 
264 /**
265  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
266  * @note: default: 1
267  * @param max_peripheral_connections
268  */
269 #ifdef ENABLE_LE_PERIPHERAL
270 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
271     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
272 }
273 #endif
274 
275 /**
276  * get hci connections iterator
277  *
278  * @return hci connections iterator
279  */
280 
281 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
282     btstack_linked_list_iterator_init(it, &hci_stack->connections);
283 }
284 
285 /**
286  * get connection for a given handle
287  *
288  * @return connection OR NULL, if not found
289  */
290 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
291     btstack_linked_list_iterator_t it;
292     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
293     while (btstack_linked_list_iterator_has_next(&it)){
294         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
295         if ( item->con_handle == con_handle ) {
296             return item;
297         }
298     }
299     return NULL;
300 }
301 
302 /**
303  * get connection for given address
304  *
305  * @return connection OR NULL, if not found
306  */
307 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
308     btstack_linked_list_iterator_t it;
309     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
310     while (btstack_linked_list_iterator_has_next(&it)){
311         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
312         if (connection->address_type != addr_type)  continue;
313         if (memcmp(addr, connection->address, 6) != 0) continue;
314         return connection;
315     }
316     return NULL;
317 }
318 
319 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
320     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
321 }
322 
323 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
324     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
325 }
326 
327 #ifdef ENABLE_CLASSIC
328 
329 #ifdef ENABLE_SCO_OVER_HCI
330 static int hci_number_sco_connections(void){
331     int connections = 0;
332     btstack_linked_list_iterator_t it;
333     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
334     while (btstack_linked_list_iterator_has_next(&it)){
335         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
336         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
337         connections++;
338     }
339     return connections;
340 }
341 #endif
342 
343 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
344     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
345 #ifdef HAVE_EMBEDDED_TICK
346     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
347         // connections might be timed out
348         hci_emit_l2cap_check_timeout(connection);
349     }
350 #else
351     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
352         // connections might be timed out
353         hci_emit_l2cap_check_timeout(connection);
354     }
355 #endif
356 }
357 
358 static void hci_connection_timestamp(hci_connection_t *connection){
359 #ifdef HAVE_EMBEDDED_TICK
360     connection->timestamp = btstack_run_loop_embedded_get_ticks();
361 #else
362     connection->timestamp = btstack_run_loop_get_time_ms();
363 #endif
364 }
365 
366 /**
367  * add authentication flags and reset timer
368  * @note: assumes classic connection
369  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
370  */
371 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
372     bd_addr_t addr;
373     reverse_bd_addr(bd_addr, addr);
374     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
375     if (conn) {
376         connectionSetAuthenticationFlags(conn, flags);
377         hci_connection_timestamp(conn);
378     }
379 }
380 
381 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
382     hci_connection_t * conn = hci_connection_for_handle(handle);
383     if (!conn) return 0;
384     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
385     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
386     return 0;
387 }
388 
389 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
390     if (!hci_stack->link_key_db) return;
391     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
392     hci_stack->link_key_db->delete_link_key(addr);
393 }
394 
395 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
396     if (!hci_stack->link_key_db) return;
397     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
398     hci_stack->link_key_db->put_link_key(addr, link_key, type);
399 }
400 
401 void gap_delete_all_link_keys(void){
402     bd_addr_t  addr;
403     link_key_t link_key;
404     link_key_type_t type;
405     btstack_link_key_iterator_t it;
406     int ok = gap_link_key_iterator_init(&it);
407     if (!ok) {
408         log_error("could not initialize iterator");
409         return;
410     }
411     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
412         gap_drop_link_key_for_bd_addr(addr);
413     }
414     gap_link_key_iterator_done(&it);
415 }
416 
417 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
418     if (!hci_stack->link_key_db) return 0;
419     if (!hci_stack->link_key_db->iterator_init) return 0;
420     return hci_stack->link_key_db->iterator_init(it);
421 }
422 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){
423     if (!hci_stack->link_key_db) return 0;
424     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
425 }
426 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
427     if (!hci_stack->link_key_db) return;
428     hci_stack->link_key_db->iterator_done(it);
429 }
430 #endif
431 
432 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
433     switch (address_type){
434         case BD_ADDR_TYPE_LE_PUBLIC:
435         case BD_ADDR_TYPE_LE_RANDOM:
436         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
437         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
438             return true;
439         default:
440             return false;
441     }
442 }
443 
444 static int hci_is_le_connection(hci_connection_t * connection){
445     return hci_is_le_connection_type(connection->address_type);
446 }
447 
448 /**
449  * count connections
450  */
451 static int nr_hci_connections(void){
452     int count = 0;
453     btstack_linked_item_t *it;
454     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
455         count++;
456     }
457     return count;
458 }
459 
460 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
461 
462     unsigned int num_packets_sent_classic = 0;
463     unsigned int num_packets_sent_le = 0;
464 
465     btstack_linked_item_t *it;
466     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
467         hci_connection_t * connection = (hci_connection_t *) it;
468         if (hci_is_le_connection(connection)){
469             num_packets_sent_le += connection->num_packets_sent;
470         }
471         if (connection->address_type == BD_ADDR_TYPE_ACL){
472             num_packets_sent_classic += connection->num_packets_sent;
473         }
474     }
475     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
476     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
477     int free_slots_le = 0;
478 
479     if (free_slots_classic < 0){
480         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);
481         return 0;
482     }
483 
484     if (hci_stack->le_acl_packets_total_num){
485         // if we have LE slots, they are used
486         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
487         if (free_slots_le < 0){
488             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);
489             return 0;
490         }
491     } else {
492         // otherwise, classic slots are used for LE, too
493         free_slots_classic -= num_packets_sent_le;
494         if (free_slots_classic < 0){
495             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);
496             return 0;
497         }
498     }
499 
500     switch (address_type){
501         case BD_ADDR_TYPE_UNKNOWN:
502             log_error("hci_number_free_acl_slots: unknown address type");
503             return 0;
504 
505         case BD_ADDR_TYPE_ACL:
506             return free_slots_classic;
507 
508         default:
509            if (hci_stack->le_acl_packets_total_num){
510                return free_slots_le;
511            }
512            return free_slots_classic;
513     }
514 }
515 
516 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
517     // get connection type
518     hci_connection_t * connection = hci_connection_for_handle(con_handle);
519     if (!connection){
520         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
521         return 0;
522     }
523     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
524 }
525 
526 #ifdef ENABLE_CLASSIC
527 static int hci_number_free_sco_slots(void){
528     unsigned int num_sco_packets_sent  = 0;
529     btstack_linked_item_t *it;
530     if (hci_stack->synchronous_flow_control_enabled){
531         // explicit flow control
532         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
533             hci_connection_t * connection = (hci_connection_t *) it;
534             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
535             num_sco_packets_sent += connection->num_packets_sent;
536         }
537         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
538             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
539             return 0;
540         }
541         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
542     } else {
543         // implicit flow control -- TODO
544         int num_ready = 0;
545         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
546             hci_connection_t * connection = (hci_connection_t *) it;
547             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
548             if (connection->sco_tx_ready == 0) continue;
549             num_ready++;
550         }
551         return num_ready;
552     }
553 }
554 #endif
555 
556 // only used to send HCI Host Number Completed Packets
557 static int hci_can_send_comand_packet_transport(void){
558     if (hci_stack->hci_packet_buffer_reserved) return 0;
559 
560     // check for async hci transport implementations
561     if (hci_stack->hci_transport->can_send_packet_now){
562         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
563             return 0;
564         }
565     }
566     return 1;
567 }
568 
569 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
570 int hci_can_send_command_packet_now(void){
571     if (hci_can_send_comand_packet_transport() == 0) return 0;
572     return hci_stack->num_cmd_packets > 0u;
573 }
574 
575 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
576     // check for async hci transport implementations
577     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
578     return hci_stack->hci_transport->can_send_packet_now(packet_type);
579 }
580 
581 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
582     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
583     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
584 }
585 
586 int hci_can_send_acl_le_packet_now(void){
587     if (hci_stack->hci_packet_buffer_reserved) return 0;
588     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
589 }
590 
591 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
592     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
593     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
594 }
595 
596 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
597     if (hci_stack->hci_packet_buffer_reserved) return 0;
598     return hci_can_send_prepared_acl_packet_now(con_handle);
599 }
600 
601 #ifdef ENABLE_CLASSIC
602 int hci_can_send_acl_classic_packet_now(void){
603     if (hci_stack->hci_packet_buffer_reserved) return 0;
604     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
605 }
606 
607 int hci_can_send_prepared_sco_packet_now(void){
608     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
609     if (hci_have_usb_transport()){
610         return hci_stack->sco_can_send_now;
611     } else {
612         return hci_number_free_sco_slots() > 0;
613     }
614 }
615 
616 int hci_can_send_sco_packet_now(void){
617     if (hci_stack->hci_packet_buffer_reserved) return 0;
618     return hci_can_send_prepared_sco_packet_now();
619 }
620 
621 void hci_request_sco_can_send_now_event(void){
622     hci_stack->sco_waiting_for_can_send_now = 1;
623     hci_notify_if_sco_can_send_now();
624 }
625 #endif
626 
627 // used for internal checks in l2cap.c
628 int hci_is_packet_buffer_reserved(void){
629     return hci_stack->hci_packet_buffer_reserved;
630 }
631 
632 // reserves outgoing packet buffer. @returns 1 if successful
633 int hci_reserve_packet_buffer(void){
634     if (hci_stack->hci_packet_buffer_reserved) {
635         log_error("hci_reserve_packet_buffer called but buffer already reserved");
636         return 0;
637     }
638     hci_stack->hci_packet_buffer_reserved = 1;
639     return 1;
640 }
641 
642 void hci_release_packet_buffer(void){
643     hci_stack->hci_packet_buffer_reserved = 0;
644 }
645 
646 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
647 static int hci_transport_synchronous(void){
648     return hci_stack->hci_transport->can_send_packet_now == NULL;
649 }
650 
651 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
652 
653     // 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);
654 
655     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
656     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
657     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
658         max_acl_data_packet_length = hci_stack->le_data_packets_length;
659     }
660 
661 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
662     if (hci_is_le_connection(connection)){
663         max_acl_data_packet_length = connection->le_max_tx_octets;
664     }
665 #endif
666 
667     log_debug("hci_send_acl_packet_fragments entered");
668 
669     int err;
670     // multiple packets could be send on a synchronous HCI transport
671     while (true){
672 
673         log_debug("hci_send_acl_packet_fragments loop entered");
674 
675         // get current data
676         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
677         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
678         int more_fragments = 0;
679 
680         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
681         if (current_acl_data_packet_length > max_acl_data_packet_length){
682             more_fragments = 1;
683             current_acl_data_packet_length = max_acl_data_packet_length;
684         }
685 
686         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
687         if (acl_header_pos > 0u){
688             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
689             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
690             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
691         }
692 
693         // update header len
694         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
695 
696         // count packet
697         connection->num_packets_sent++;
698         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
699 
700         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
701         if (more_fragments){
702             // update start of next fragment to send
703             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
704         } else {
705             // done
706             hci_stack->acl_fragmentation_pos = 0;
707             hci_stack->acl_fragmentation_total_size = 0;
708         }
709 
710         // send packet
711         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
712         const int size = current_acl_data_packet_length + 4;
713         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
714         hci_stack->acl_fragmentation_tx_active = 1;
715         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
716 
717         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
718 
719         // done yet?
720         if (!more_fragments) break;
721 
722         // can send more?
723         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
724     }
725 
726     log_debug("hci_send_acl_packet_fragments loop over");
727 
728     // release buffer now for synchronous transport
729     if (hci_transport_synchronous()){
730         hci_stack->acl_fragmentation_tx_active = 0;
731         hci_release_packet_buffer();
732         hci_emit_transport_packet_sent();
733     }
734 
735     return err;
736 }
737 
738 // pre: caller has reserved the packet buffer
739 int hci_send_acl_packet_buffer(int size){
740 
741     // log_info("hci_send_acl_packet_buffer size %u", size);
742 
743     if (!hci_stack->hci_packet_buffer_reserved) {
744         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
745         return 0;
746     }
747 
748     uint8_t * packet = hci_stack->hci_packet_buffer;
749     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
750 
751     // check for free places on Bluetooth module
752     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
753         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
754         hci_release_packet_buffer();
755         hci_emit_transport_packet_sent();
756         return BTSTACK_ACL_BUFFERS_FULL;
757     }
758 
759     hci_connection_t *connection = hci_connection_for_handle( con_handle);
760     if (!connection) {
761         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
762         hci_release_packet_buffer();
763         hci_emit_transport_packet_sent();
764         return 0;
765     }
766 
767 #ifdef ENABLE_CLASSIC
768     hci_connection_timestamp(connection);
769 #endif
770 
771     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
772 
773     // setup data
774     hci_stack->acl_fragmentation_total_size = size;
775     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
776 
777     return hci_send_acl_packet_fragments(connection);
778 }
779 
780 #ifdef ENABLE_CLASSIC
781 // pre: caller has reserved the packet buffer
782 int hci_send_sco_packet_buffer(int size){
783 
784     // log_info("hci_send_acl_packet_buffer size %u", size);
785 
786     if (!hci_stack->hci_packet_buffer_reserved) {
787         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
788         return 0;
789     }
790 
791     uint8_t * packet = hci_stack->hci_packet_buffer;
792 
793     // skip checks in loopback mode
794     if (!hci_stack->loopback_mode){
795         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
796 
797         // check for free places on Bluetooth module
798         if (!hci_can_send_prepared_sco_packet_now()) {
799             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
800             hci_release_packet_buffer();
801             hci_emit_transport_packet_sent();
802             return BTSTACK_ACL_BUFFERS_FULL;
803         }
804 
805         // track send packet in connection struct
806         hci_connection_t *connection = hci_connection_for_handle( con_handle);
807         if (!connection) {
808             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
809             hci_release_packet_buffer();
810             hci_emit_transport_packet_sent();
811             return 0;
812         }
813 
814         if (hci_have_usb_transport()){
815             // token used
816             hci_stack->sco_can_send_now = 0;
817         } else {
818             if (hci_stack->synchronous_flow_control_enabled){
819                 connection->num_packets_sent++;
820             } else {
821                 connection->sco_tx_ready--;
822             }
823         }
824     }
825 
826     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
827     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
828 
829     if (hci_transport_synchronous()){
830         hci_release_packet_buffer();
831         hci_emit_transport_packet_sent();
832     }
833 
834     return err;
835 }
836 #endif
837 
838 static void acl_handler(uint8_t *packet, uint16_t size){
839 
840     // get info
841     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
842     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
843     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
844     uint16_t acl_length         = READ_ACL_LENGTH(packet);
845 
846     // ignore non-registered handle
847     if (!conn){
848         log_error("acl_handler called with non-registered handle %u!" , con_handle);
849         return;
850     }
851 
852     // assert packet is complete
853     if ((acl_length + 4u) != size){
854         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
855         return;
856     }
857 
858 #ifdef ENABLE_CLASSIC
859     // update idle timestamp
860     hci_connection_timestamp(conn);
861 #endif
862 
863 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
864     hci_stack->host_completed_packets = 1;
865     conn->num_packets_completed++;
866 #endif
867 
868     // handle different packet types
869     switch (acl_flags & 0x03u) {
870 
871         case 0x01: // continuation fragment
872 
873             // sanity checks
874             if (conn->acl_recombination_pos == 0u) {
875                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
876                 return;
877             }
878             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
879                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
880                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
881                 conn->acl_recombination_pos = 0;
882                 return;
883             }
884 
885             // append fragment payload (header already stored)
886             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
887                          &packet[4], acl_length);
888             conn->acl_recombination_pos += acl_length;
889 
890             // forward complete L2CAP packet if complete.
891             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
892                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
893                 // reset recombination buffer
894                 conn->acl_recombination_length = 0;
895                 conn->acl_recombination_pos = 0;
896             }
897             break;
898 
899         case 0x02: { // first fragment
900 
901             // sanity check
902             if (conn->acl_recombination_pos) {
903                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
904                 conn->acl_recombination_pos = 0;
905             }
906 
907             // peek into L2CAP packet!
908             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
909 
910             // compare fragment size to L2CAP packet size
911             if (acl_length >= (l2cap_length + 4u)){
912                 // forward fragment as L2CAP packet
913                 hci_emit_acl_packet(packet, acl_length + 4u);
914             } else {
915 
916                 if (acl_length > HCI_ACL_BUFFER_SIZE){
917                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
918                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
919                     return;
920                 }
921 
922                 // store first fragment and tweak acl length for complete package
923                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
924                              packet, acl_length + 4u);
925                 conn->acl_recombination_pos    = acl_length + 4u;
926                 conn->acl_recombination_length = l2cap_length;
927                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
928             }
929             break;
930 
931         }
932         default:
933             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
934             return;
935     }
936 
937     // execute main loop
938     hci_run();
939 }
940 
941 static void hci_shutdown_connection(hci_connection_t *conn){
942     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
943 
944 #ifdef ENABLE_CLASSIC
945 #ifdef ENABLE_SCO_OVER_HCI
946     int addr_type = conn->address_type;
947 #endif
948 #endif
949 
950     btstack_run_loop_remove_timer(&conn->timeout);
951 
952     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
953     btstack_memory_hci_connection_free( conn );
954 
955     // now it's gone
956     hci_emit_nr_connections_changed();
957 
958 #ifdef ENABLE_CLASSIC
959 #ifdef ENABLE_SCO_OVER_HCI
960     // update SCO
961     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
962         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
963     }
964 #endif
965 #endif
966 }
967 
968 #ifdef ENABLE_CLASSIC
969 
970 static const uint16_t packet_type_sizes[] = {
971     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
972     HCI_ACL_DH1_SIZE, 0, 0, 0,
973     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
974     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
975 };
976 static const uint8_t  packet_type_feature_requirement_bit[] = {
977      0, // 3 slot packets
978      1, // 5 slot packets
979     25, // EDR 2 mpbs
980     26, // EDR 3 mbps
981     39, // 3 slot EDR packts
982     40, // 5 slot EDR packet
983 };
984 static const uint16_t packet_type_feature_packet_mask[] = {
985     0x0f00, // 3 slot packets
986     0xf000, // 5 slot packets
987     0x1102, // EDR 2 mpbs
988     0x2204, // EDR 3 mbps
989     0x0300, // 3 slot EDR packts
990     0x3000, // 5 slot EDR packet
991 };
992 
993 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
994     // enable packet types based on size
995     uint16_t packet_types = 0;
996     unsigned int i;
997     for (i=0;i<16;i++){
998         if (packet_type_sizes[i] == 0) continue;
999         if (packet_type_sizes[i] <= buffer_size){
1000             packet_types |= 1 << i;
1001         }
1002     }
1003     // disable packet types due to missing local supported features
1004     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1005         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1006         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1007         if (feature_set) continue;
1008         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1009         packet_types &= ~packet_type_feature_packet_mask[i];
1010     }
1011     // flip bits for "may not be used"
1012     packet_types ^= 0x3306;
1013     return packet_types;
1014 }
1015 
1016 uint16_t hci_usable_acl_packet_types(void){
1017     return hci_stack->packet_types;
1018 }
1019 #endif
1020 
1021 uint8_t* hci_get_outgoing_packet_buffer(void){
1022     // hci packet buffer is >= acl data packet length
1023     return hci_stack->hci_packet_buffer;
1024 }
1025 
1026 uint16_t hci_max_acl_data_packet_length(void){
1027     return hci_stack->acl_data_packet_length;
1028 }
1029 
1030 #ifdef ENABLE_CLASSIC
1031 int hci_extended_sco_link_supported(void){
1032     // No. 31, byte 3, bit 7
1033     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1034 }
1035 #endif
1036 
1037 int hci_non_flushable_packet_boundary_flag_supported(void){
1038     // No. 54, byte 6, bit 6
1039     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1040 }
1041 
1042 static int gap_ssp_supported(void){
1043     // No. 51, byte 6, bit 3
1044     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1045 }
1046 
1047 static int hci_classic_supported(void){
1048 #ifdef ENABLE_CLASSIC
1049     // No. 37, byte 4, bit 5, = No BR/EDR Support
1050     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1051 #else
1052     return 0;
1053 #endif
1054 }
1055 
1056 static int hci_le_supported(void){
1057 #ifdef ENABLE_BLE
1058     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1059     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1060 #else
1061     return 0;
1062 #endif
1063 }
1064 
1065 #ifdef ENABLE_BLE
1066 
1067 /**
1068  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1069  */
1070 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1071     *addr_type = hci_stack->le_own_addr_type;
1072     if (hci_stack->le_own_addr_type){
1073         (void)memcpy(addr, hci_stack->le_random_address, 6);
1074     } else {
1075         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1076     }
1077 }
1078 
1079 #ifdef ENABLE_LE_CENTRAL
1080 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1081 
1082     int offset = 3;
1083     int num_reports = packet[offset];
1084     offset += 1;
1085 
1086     int i;
1087     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1088     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1089     for (i=0; (i<num_reports) && (offset < size);i++){
1090         // sanity checks on data_length:
1091         uint8_t data_length = packet[offset + 8];
1092         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1093         if ((offset + 9u + data_length + 1u) > size)    return;
1094         // setup event
1095         uint8_t event_size = 10u + data_length;
1096         int pos = 0;
1097         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1098         event[pos++] = event_size;
1099         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1100         offset += 8;
1101         pos += 8;
1102         event[pos++] = packet[offset + 1 + data_length]; // rssi
1103         event[pos++] = data_length;
1104         offset++;
1105         (void)memcpy(&event[pos], &packet[offset], data_length);
1106         pos +=    data_length;
1107         offset += data_length + 1u; // rssi
1108         hci_emit_event(event, pos, 1);
1109     }
1110 }
1111 #endif
1112 #endif
1113 
1114 #ifdef ENABLE_BLE
1115 #ifdef ENABLE_LE_PERIPHERAL
1116 static void hci_update_advertisements_enabled_for_current_roles(void){
1117     if (hci_stack->le_advertisements_enabled){
1118         // get number of active le slave connections
1119         int num_slave_connections = 0;
1120         btstack_linked_list_iterator_t it;
1121         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1122         while (btstack_linked_list_iterator_has_next(&it)){
1123             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1124             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1125             if (con->state != OPEN) continue;
1126             if (con->role  != HCI_ROLE_SLAVE) continue;
1127             if (!hci_is_le_connection(con)) continue;
1128             num_slave_connections++;
1129         }
1130         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1131         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1132     } else {
1133         hci_stack->le_advertisements_enabled_for_current_roles = false;
1134     }
1135 }
1136 #endif
1137 #endif
1138 
1139 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1140 
1141 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1142     if (!hci_stack->config) return 0;
1143     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1144     // Limit baud rate for Broadcom chipsets to 3 mbps
1145     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1146         baud_rate = 3000000;
1147     }
1148     return baud_rate;
1149 }
1150 
1151 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1152     UNUSED(ds);
1153 
1154     switch (hci_stack->substate){
1155         case HCI_INIT_W4_SEND_RESET:
1156             log_info("Resend HCI Reset");
1157             hci_stack->substate = HCI_INIT_SEND_RESET;
1158             hci_stack->num_cmd_packets = 1;
1159             hci_run();
1160             break;
1161         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1162             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1163             if (hci_stack->hci_transport->reset_link){
1164                 hci_stack->hci_transport->reset_link();
1165             }
1166 
1167             /* fall through */
1168 
1169         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1170             log_info("Resend HCI Reset - CSR Warm Boot");
1171             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1172             hci_stack->num_cmd_packets = 1;
1173             hci_run();
1174             break;
1175         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1176             if (hci_stack->hci_transport->set_baudrate){
1177                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1178                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1179                 hci_stack->hci_transport->set_baudrate(baud_rate);
1180             }
1181             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1182             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1183                 if (hci_stack->hci_transport->reset_link){
1184                     log_info("Link Reset");
1185                     hci_stack->hci_transport->reset_link();
1186                 }
1187                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1188                 hci_run();
1189             }
1190             break;
1191         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1192             // otherwise continue
1193             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1194             hci_send_cmd(&hci_read_local_supported_commands);
1195             break;
1196         default:
1197             break;
1198     }
1199 }
1200 #endif
1201 
1202 static void hci_initializing_next_state(void){
1203     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1204 }
1205 
1206 // assumption: hci_can_send_command_packet_now() == true
1207 static void hci_initializing_run(void){
1208     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1209     switch (hci_stack->substate){
1210         case HCI_INIT_SEND_RESET:
1211             hci_state_reset();
1212 
1213 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1214             // prepare reset if command complete not received in 100ms
1215             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1216             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1217             btstack_run_loop_add_timer(&hci_stack->timeout);
1218 #endif
1219             // send command
1220             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1221             hci_send_cmd(&hci_reset);
1222             break;
1223         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1224             hci_send_cmd(&hci_read_local_version_information);
1225             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1226             break;
1227         case HCI_INIT_SEND_READ_LOCAL_NAME:
1228             hci_send_cmd(&hci_read_local_name);
1229             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1230             break;
1231 
1232 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1233         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1234             hci_state_reset();
1235             // prepare reset if command complete not received in 100ms
1236             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1237             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1238             btstack_run_loop_add_timer(&hci_stack->timeout);
1239             // send command
1240             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1241             hci_send_cmd(&hci_reset);
1242             break;
1243         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1244             hci_state_reset();
1245             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1246             hci_send_cmd(&hci_reset);
1247             break;
1248         case HCI_INIT_SEND_BAUD_CHANGE: {
1249             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1250             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1251             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1252             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1253             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1254             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1255             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1256             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1257                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1258                 btstack_run_loop_add_timer(&hci_stack->timeout);
1259             }
1260             break;
1261         }
1262         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1263             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1264             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1265             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1266             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1267             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1268             break;
1269         }
1270         case HCI_INIT_CUSTOM_INIT:
1271             // Custom initialization
1272             if (hci_stack->chipset && hci_stack->chipset->next_command){
1273                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1274                 int send_cmd = 0;
1275                 switch (hci_stack->chipset_result){
1276                     case BTSTACK_CHIPSET_VALID_COMMAND:
1277                         send_cmd = 1;
1278                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1279                         break;
1280                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1281                         send_cmd = 1;
1282                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1283                         log_info("CSR Warm Boot");
1284                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1285                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1286                         btstack_run_loop_add_timer(&hci_stack->timeout);
1287                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1288                             && hci_stack->config
1289                             && hci_stack->chipset
1290                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1291                             && hci_stack->hci_transport->set_baudrate
1292                             && hci_transport_uart_get_main_baud_rate()){
1293                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1294                         } else {
1295                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1296                         }
1297                         break;
1298                     default:
1299                         break;
1300                 }
1301 
1302                 if (send_cmd){
1303                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1304                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1305                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1306                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1307                     break;
1308                 }
1309                 log_info("Init script done");
1310 
1311                 // Init script download on Broadcom chipsets causes:
1312                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1313                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1314                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1315 
1316                     // - baud rate to reset, restore UART baud rate if needed
1317                     int need_baud_change = hci_stack->config
1318                         && hci_stack->chipset
1319                         && hci_stack->chipset->set_baudrate_command
1320                         && hci_stack->hci_transport->set_baudrate
1321                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1322                     if (need_baud_change) {
1323                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1324                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1325                         hci_stack->hci_transport->set_baudrate(baud_rate);
1326                     }
1327 
1328                     uint16_t bcm_delay_ms = 300;
1329                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1330                     //   -> Work around: wait here.
1331                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1332                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1333                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1334                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1335                     btstack_run_loop_add_timer(&hci_stack->timeout);
1336                     break;
1337                 }
1338             }
1339             // otherwise continue
1340             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1341             hci_send_cmd(&hci_read_local_supported_commands);
1342             break;
1343         case HCI_INIT_SET_BD_ADDR:
1344             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1345             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1346             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1347             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1348             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1349             break;
1350 #endif
1351 
1352         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1353             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1354             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1355             hci_send_cmd(&hci_read_local_supported_commands);
1356             break;
1357         case HCI_INIT_READ_BD_ADDR:
1358             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1359             hci_send_cmd(&hci_read_bd_addr);
1360             break;
1361         case HCI_INIT_READ_BUFFER_SIZE:
1362             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1363             hci_send_cmd(&hci_read_buffer_size);
1364             break;
1365         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1366             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1367             hci_send_cmd(&hci_read_local_supported_features);
1368             break;
1369 
1370 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1371         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1372             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1373             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1374             break;
1375         case HCI_INIT_HOST_BUFFER_SIZE:
1376             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1377             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1378                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1379             break;
1380 #endif
1381 
1382         case HCI_INIT_SET_EVENT_MASK:
1383             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1384             if (hci_le_supported()){
1385                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1386             } else {
1387                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1388                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1389             }
1390             break;
1391 
1392 #ifdef ENABLE_CLASSIC
1393         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1394             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1395             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1396             break;
1397         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1398             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1399             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1400             break;
1401         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1403             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1404             break;
1405         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1407             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1408             break;
1409         case HCI_INIT_WRITE_LOCAL_NAME: {
1410             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1411             hci_reserve_packet_buffer();
1412             uint8_t * packet = hci_stack->hci_packet_buffer;
1413             // construct HCI Command and send
1414             uint16_t opcode = hci_write_local_name.opcode;
1415             hci_stack->last_cmd_opcode = opcode;
1416             packet[0] = opcode & 0xff;
1417             packet[1] = opcode >> 8;
1418             packet[2] = DEVICE_NAME_LEN;
1419             memset(&packet[3], 0, DEVICE_NAME_LEN);
1420             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1421             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1422             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1423             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1424             // expand '00:00:00:00:00:00' in name with bd_addr
1425             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1426             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1427             break;
1428         }
1429         case HCI_INIT_WRITE_EIR_DATA: {
1430             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1431             hci_reserve_packet_buffer();
1432             uint8_t * packet = hci_stack->hci_packet_buffer;
1433             // construct HCI Command in-place and send
1434             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1435             hci_stack->last_cmd_opcode = opcode;
1436             uint16_t offset = 0;
1437             packet[offset++] = opcode & 0xff;
1438             packet[offset++] = opcode >> 8;
1439             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1440             packet[offset++] = 0;  // FEC not required
1441             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1442             if (hci_stack->eir_data){
1443                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1444                 ad_context_t context;
1445                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1446                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1447                     uint8_t size        = ad_iterator_get_data_len(&context);
1448                     const uint8_t *data = ad_iterator_get_data(&context);
1449                     // copy item
1450                     packet[offset++] = size + 1;
1451                     packet[offset++] = data_type;
1452                     memcpy(&packet[offset], data, size);
1453                     // update name item
1454                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1455                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1456                     }
1457                     offset += size;
1458                 }
1459             } else {
1460                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1461                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1462                 packet[offset++] = bytes_to_copy + 1;
1463                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1464                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1465                 // expand '00:00:00:00:00:00' in name with bd_addr
1466                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1467             }
1468             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1469             break;
1470         }
1471         case HCI_INIT_WRITE_INQUIRY_MODE:
1472             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1473             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1474             break;
1475         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1476             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1477             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1478             break;
1479         case HCI_INIT_WRITE_SCAN_ENABLE:
1480             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1481             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1482             break;
1483         // only sent if ENABLE_SCO_OVER_HCI is defined
1484         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1485             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1486             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1487             break;
1488         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1489             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1490             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1491             break;
1492         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1493         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1494             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1495             log_info("BCM: Route SCO data via HCI transport");
1496             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1497             break;
1498 
1499 #endif
1500 #ifdef ENABLE_BLE
1501         // LE INIT
1502         case HCI_INIT_LE_READ_BUFFER_SIZE:
1503             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1504             hci_send_cmd(&hci_le_read_buffer_size);
1505             break;
1506         case HCI_INIT_LE_SET_EVENT_MASK:
1507             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1508             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1509             break;
1510         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1511             // LE Supported Host = 1, Simultaneous Host = 0
1512             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1513             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1514             break;
1515 #endif
1516 
1517 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1518         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1519             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1520             hci_send_cmd(&hci_le_read_maximum_data_length);
1521             break;
1522         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1523             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1524             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1525             break;
1526 #endif
1527 
1528 #ifdef ENABLE_LE_CENTRAL
1529         case HCI_INIT_READ_WHITE_LIST_SIZE:
1530             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1531             hci_send_cmd(&hci_le_read_white_list_size);
1532             break;
1533         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1534             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1535             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);
1536             break;
1537 #endif
1538         default:
1539             return;
1540     }
1541 }
1542 
1543 static void hci_init_done(void){
1544     // done. tell the app
1545     log_info("hci_init_done -> HCI_STATE_WORKING");
1546     hci_stack->state = HCI_STATE_WORKING;
1547     hci_emit_state();
1548     hci_run();
1549 }
1550 
1551 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1552     bool command_completed = false;
1553     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1554         uint16_t opcode = little_endian_read_16(packet,3);
1555         if (opcode == hci_stack->last_cmd_opcode){
1556             command_completed = true;
1557             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1558         } else {
1559             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1560         }
1561     }
1562 
1563     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1564         uint8_t  status = packet[2];
1565         uint16_t opcode = little_endian_read_16(packet,4);
1566         if (opcode == hci_stack->last_cmd_opcode){
1567             if (status){
1568                 command_completed = true;
1569                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1570             } else {
1571                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1572             }
1573         } else {
1574             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1575         }
1576     }
1577 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1578     // Vendor == CSR
1579     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1580         // TODO: track actual command
1581         command_completed = true;
1582     }
1583 
1584     // Vendor == Toshiba
1585     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1586         // TODO: track actual command
1587         command_completed = true;
1588         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1589         hci_stack->num_cmd_packets = 1;
1590     }
1591 #endif
1592 
1593     return command_completed;
1594 }
1595 
1596 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1597 
1598     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1599 
1600     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1601 
1602 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1603 
1604     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1605     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1606     //
1607     // HCI Reset
1608     // Timeout 100 ms
1609     // HCI Reset
1610     // Command Complete Reset
1611     // HCI Read Local Version Information
1612     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1613     // hang...
1614     //
1615     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1616     if (!command_completed
1617             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1618             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1619 
1620         uint16_t opcode = little_endian_read_16(packet,3);
1621         if (opcode == hci_reset.opcode){
1622             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1623             return;
1624         }
1625     }
1626 
1627     // CSR & H5
1628     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1629     if (!command_completed
1630             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1631             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1632 
1633         uint16_t opcode = little_endian_read_16(packet,3);
1634         if (opcode == hci_reset.opcode){
1635             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1636             return;
1637         }
1638     }
1639 
1640     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1641     // fix: Correct substate and behave as command below
1642     if (command_completed){
1643         switch (hci_stack->substate){
1644             case HCI_INIT_SEND_RESET:
1645                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1646                 break;
1647             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1648                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1649                 break;
1650             default:
1651                 break;
1652         }
1653     }
1654 
1655 #endif
1656 
1657     if (!command_completed) return;
1658 
1659     bool need_baud_change = false;
1660     bool need_addr_change = false;
1661 
1662 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1663     need_baud_change = hci_stack->config
1664                         && hci_stack->chipset
1665                         && hci_stack->chipset->set_baudrate_command
1666                         && hci_stack->hci_transport->set_baudrate
1667                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1668 
1669     need_addr_change = hci_stack->custom_bd_addr_set
1670                         && hci_stack->chipset
1671                         && hci_stack->chipset->set_bd_addr_command;
1672 #endif
1673 
1674     switch(hci_stack->substate){
1675 
1676 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1677         case HCI_INIT_SEND_RESET:
1678             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1679             // fix: just correct substate and behave as command below
1680             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1681             btstack_run_loop_remove_timer(&hci_stack->timeout);
1682             break;
1683         case HCI_INIT_W4_SEND_RESET:
1684             btstack_run_loop_remove_timer(&hci_stack->timeout);
1685             break;
1686         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1687             log_info("Received local name, need baud change %d", (int) need_baud_change);
1688             if (need_baud_change){
1689                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1690                 return;
1691             }
1692             // skip baud change
1693             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1694             return;
1695         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1696             // for STLC2500D, baud rate change already happened.
1697             // for others, baud rate gets changed now
1698             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1699                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1700                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1701                 hci_stack->hci_transport->set_baudrate(baud_rate);
1702             }
1703             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1704             return;
1705         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1706             btstack_run_loop_remove_timer(&hci_stack->timeout);
1707             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1708             return;
1709         case HCI_INIT_W4_CUSTOM_INIT:
1710             // repeat custom init
1711             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1712             return;
1713 #else
1714         case HCI_INIT_W4_SEND_RESET:
1715             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1716             return ;
1717 #endif
1718 
1719         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1720             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1721               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1722                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1723                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1724                 return;
1725             }
1726             if (need_addr_change){
1727                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1728                 return;
1729             }
1730             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1731             return;
1732 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1733         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1734             if (need_baud_change){
1735                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1736                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1737                 hci_stack->hci_transport->set_baudrate(baud_rate);
1738             }
1739             if (need_addr_change){
1740                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1741                 return;
1742             }
1743             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1744             return;
1745         case HCI_INIT_W4_SET_BD_ADDR:
1746             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1747             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1748             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1749                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1750                 return;
1751             }
1752             // skipping st warm boot
1753             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1754             return;
1755         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1756             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1757             return;
1758 #endif
1759         case HCI_INIT_W4_READ_BD_ADDR:
1760             // only read buffer size if supported
1761             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1762                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1763                 return;
1764             }
1765             // skipping read buffer size
1766             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1767             return;
1768         case HCI_INIT_W4_SET_EVENT_MASK:
1769             // skip Classic init commands for LE only chipsets
1770             if (!hci_classic_supported()){
1771 #ifdef ENABLE_BLE
1772                 if (hci_le_supported()){
1773                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1774                     return;
1775                 }
1776 #endif
1777                 log_error("Neither BR/EDR nor LE supported");
1778                 hci_init_done();
1779                 return;
1780             }
1781             if (!gap_ssp_supported()){
1782                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1783                 return;
1784             }
1785             break;
1786 #ifdef ENABLE_BLE
1787         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1788             // skip write le host if not supported (e.g. on LE only EM9301)
1789             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1790             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1791             return;
1792 
1793 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1794         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1795             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1796             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1797                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1798                 return;
1799             }
1800             // explicit fall through to reduce repetitions
1801 
1802 #ifdef ENABLE_LE_CENTRAL
1803             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1804 #else
1805             hci_init_done();
1806 #endif
1807             return;
1808 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1809 
1810 #endif  /* ENABLE_BLE */
1811 
1812         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1813             // skip write secure connections host support if not supported or disabled
1814             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1815                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1816                 return;
1817             }
1818             break;
1819 
1820 #ifdef ENABLE_SCO_OVER_HCI
1821         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1822             // skip write synchronous flow control if not supported
1823             if (hci_stack->local_supported_commands[0] & 0x04) break;
1824             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1825 
1826             /* fall through */
1827 
1828         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1829             // skip write default erroneous data reporting if not supported
1830             if (hci_stack->local_supported_commands[0] & 0x08) break;
1831             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1832 
1833             /* fall through */
1834 
1835         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1836             // skip bcm set sco pcm config on non-Broadcom chipsets
1837             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1838             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1839 
1840             /* fall through */
1841 
1842         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1843             if (!hci_le_supported()){
1844                 // SKIP LE init for Classic only configuration
1845                 hci_init_done();
1846                 return;
1847             }
1848             break;
1849 
1850 #else /* !ENABLE_SCO_OVER_HCI */
1851 
1852         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1853 #ifdef ENABLE_BLE
1854             if (hci_le_supported()){
1855                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1856                 return;
1857             }
1858 #endif
1859             // SKIP LE init for Classic only configuration
1860             hci_init_done();
1861             return;
1862 #endif /* ENABLE_SCO_OVER_HCI */
1863 
1864 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1865 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1866         // Response to command before init done state -> init done
1867         case (HCI_INIT_DONE-1):
1868             hci_init_done();
1869             return;
1870 #endif
1871 
1872         default:
1873             break;
1874     }
1875     hci_initializing_next_state();
1876 }
1877 
1878 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1879     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1880     bd_addr_t bd_address;
1881     (void)memcpy(&bd_address, conn->address, 6);
1882 
1883 #ifdef ENABLE_CLASSIC
1884     // cache needed data
1885     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1886 #endif
1887 
1888     // connection failed, remove entry
1889     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1890     btstack_memory_hci_connection_free( conn );
1891 
1892 #ifdef ENABLE_CLASSIC
1893     // notify client if dedicated bonding
1894     if (notify_dedicated_bonding_failed){
1895         log_info("hci notify_dedicated_bonding_failed");
1896         hci_emit_dedicated_bonding_result(bd_address, status);
1897     }
1898 
1899     // if authentication error, also delete link key
1900     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1901         gap_drop_link_key_for_bd_addr(bd_address);
1902     }
1903 #else
1904     UNUSED(status);
1905 #endif
1906 }
1907 
1908 #ifdef ENABLE_CLASSIC
1909 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1910     // SSP Controller
1911     if (features[6] & (1 << 3)){
1912         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1913     }
1914     // eSCO
1915     if (features[3] & (1<<7)){
1916         conn->remote_supported_features[0] |= 1;
1917     }
1918     // Extended features
1919     if (features[7] & (1<<7)){
1920         conn->remote_supported_features[0] |= 2;
1921     }
1922 }
1923 
1924 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1925     // SSP Host
1926     if (features[0] & (1 << 0)){
1927         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1928     }
1929     // SC Host
1930     if (features[0] & (1 << 3)){
1931         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1932     }
1933 }
1934 
1935 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1936     // SC Controller
1937     if (features[1] & (1 << 0)){
1938         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1939     }
1940 }
1941 
1942 static void hci_handle_remote_features_received(hci_connection_t * conn){
1943     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1944     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1945     if (conn->bonding_flags & BONDING_DEDICATED){
1946         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1947     }
1948 }
1949 #endif
1950 
1951 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1952     // handle BT initialization
1953     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1954         hci_initializing_event_handler(packet, size);
1955     }
1956 
1957     // help with BT sleep
1958     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1959         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1960         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1961         hci_initializing_next_state();
1962     }
1963 }
1964 
1965 #ifdef ENABLE_CLASSIC
1966 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1967     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1968     conn->encryption_key_size = encryption_key_size;
1969 
1970     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1971         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1972         return;
1973     }
1974 
1975     // Request Authentication if not already done
1976     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1977     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1978 }
1979 #endif
1980 
1981 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1982     UNUSED(size);
1983 
1984     uint16_t manufacturer;
1985 #ifdef ENABLE_CLASSIC
1986     hci_con_handle_t handle;
1987     hci_connection_t * conn;
1988     uint8_t status;
1989 #endif
1990     // get num cmd packets - limit to 1 to reduce complexity
1991     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1992 
1993     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
1994     switch (opcode){
1995         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
1996             if (packet[5]) break;
1997             // terminate, name 248 chars
1998             packet[6+248] = 0;
1999             log_info("local name: %s", &packet[6]);
2000             break;
2001         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2002             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2003             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2004                 uint16_t acl_len = little_endian_read_16(packet, 6);
2005                 uint16_t sco_len = packet[8];
2006 
2007                 // determine usable ACL/SCO payload size
2008                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2009                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2010 
2011                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2012                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2013 
2014                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2015                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2016                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2017             }
2018             break;
2019         case HCI_OPCODE_HCI_READ_RSSI:
2020             if (packet[5] == ERROR_CODE_SUCCESS){
2021                 uint8_t event[5];
2022                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2023                 event[1] = 3;
2024                 (void)memcpy(&event[2], &packet[6], 3);
2025                 hci_emit_event(event, sizeof(event), 1);
2026             }
2027             break;
2028 #ifdef ENABLE_BLE
2029         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2030             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2031             hci_stack->le_acl_packets_total_num = packet[8];
2032             // determine usable ACL payload size
2033             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2034                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2035             }
2036             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2037             break;
2038 #endif
2039 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2040         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2041             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2042             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2043             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);
2044             break;
2045 #endif
2046 #ifdef ENABLE_LE_CENTRAL
2047         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2048             hci_stack->le_whitelist_capacity = packet[6];
2049             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2050             break;
2051 #endif
2052         case HCI_OPCODE_HCI_READ_BD_ADDR:
2053             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2054             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));
2055 #ifdef ENABLE_CLASSIC
2056             if (hci_stack->link_key_db){
2057                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2058             }
2059 #endif
2060             break;
2061 #ifdef ENABLE_CLASSIC
2062         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2063             hci_emit_discoverable_enabled(hci_stack->discoverable);
2064             break;
2065         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2066             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2067                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2068                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2069                 hci_emit_event(event, sizeof(event), 1);
2070             }
2071             break;
2072 #endif
2073         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2074             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2075 
2076 #ifdef ENABLE_CLASSIC
2077             // determine usable ACL packet types based on host buffer size and supported features
2078             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2079             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2080 #endif
2081             // Classic/LE
2082             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2083             break;
2084         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2085             manufacturer = little_endian_read_16(packet, 10);
2086             // map Cypress to Broadcom
2087             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2088                 log_info("Treat Cypress as Broadcom");
2089                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2090                 little_endian_store_16(packet, 10, manufacturer);
2091             }
2092             hci_stack->manufacturer = manufacturer;
2093             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2094             break;
2095         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2096             hci_stack->local_supported_commands[0] =
2097                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2098                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2099                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2100                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2101                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2102                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2103                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2104                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2105             hci_stack->local_supported_commands[1] =
2106                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2107                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2108             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2109             break;
2110 #ifdef ENABLE_CLASSIC
2111         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2112             if (packet[5]) return;
2113             hci_stack->synchronous_flow_control_enabled = 1;
2114             break;
2115         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2116             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2117             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2118             conn   = hci_connection_for_handle(handle);
2119             if (conn != NULL) {
2120                 uint8_t key_size = 0;
2121                 if (status == 0){
2122                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2123                     log_info("Handle %04x key Size: %u", handle, key_size);
2124                 } else {
2125                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2126                 }
2127                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2128             }
2129             break;
2130 #endif
2131         default:
2132             break;
2133     }
2134 }
2135 
2136 static void event_handler(uint8_t *packet, uint16_t size){
2137 
2138     uint16_t event_length = packet[1];
2139 
2140     // assert packet is complete
2141     if (size != (event_length + 2u)){
2142         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2143         return;
2144     }
2145 
2146     bd_addr_t addr;
2147     bd_addr_type_t addr_type;
2148     hci_con_handle_t handle;
2149     hci_connection_t * conn;
2150     int i;
2151     int create_connection_cmd;
2152 
2153 #ifdef ENABLE_CLASSIC
2154     uint8_t link_type;
2155 #endif
2156 
2157     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2158 
2159     switch (hci_event_packet_get_type(packet)) {
2160 
2161         case HCI_EVENT_COMMAND_COMPLETE:
2162             handle_command_complete_event(packet, size);
2163             break;
2164 
2165         case HCI_EVENT_COMMAND_STATUS:
2166             // get num cmd packets - limit to 1 to reduce complexity
2167             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2168 
2169             // check command status to detected failed outgoing connections
2170             create_connection_cmd = 0;
2171 #ifdef ENABLE_CLASSIC
2172             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2173                 create_connection_cmd = 1;
2174             }
2175 #endif
2176 #ifdef ENABLE_LE_CENTRAL
2177             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2178                 create_connection_cmd = 1;
2179             }
2180 #endif
2181             if (create_connection_cmd) {
2182                 uint8_t status = hci_event_command_status_get_status(packet);
2183                 addr_type = hci_stack->outgoing_addr_type;
2184                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2185                 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);
2186 
2187                 // reset outgoing address info
2188                 memset(hci_stack->outgoing_addr, 0, 6);
2189                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2190 
2191                 // on error
2192                 if (status != ERROR_CODE_SUCCESS){
2193 #ifdef ENABLE_LE_CENTRAL
2194                     if (hci_is_le_connection_type(addr_type)){
2195                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2196                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2197                     }
2198 #endif
2199                     // error => outgoing connection failed
2200                     if (conn != NULL){
2201                         hci_handle_connection_failed(conn, status);
2202                     }
2203                 }
2204             }
2205             break;
2206 
2207         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2208             if (size < 3) return;
2209             uint16_t num_handles = packet[2];
2210             if (size != (3u + num_handles * 4u)) return;
2211             uint16_t offset = 3;
2212             for (i=0; i<num_handles;i++){
2213                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2214                 offset += 2u;
2215                 uint16_t num_packets = little_endian_read_16(packet, offset);
2216                 offset += 2u;
2217 
2218                 conn = hci_connection_for_handle(handle);
2219                 if (!conn){
2220                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2221                     continue;
2222                 }
2223 
2224                 if (conn->num_packets_sent >= num_packets){
2225                     conn->num_packets_sent -= num_packets;
2226                 } else {
2227                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2228                     conn->num_packets_sent = 0;
2229                 }
2230                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2231 
2232 #ifdef ENABLE_CLASSIC
2233                 // For SCO, we do the can_send_now_check here
2234                 hci_notify_if_sco_can_send_now();
2235 #endif
2236             }
2237             break;
2238         }
2239 
2240 #ifdef ENABLE_CLASSIC
2241         case HCI_EVENT_INQUIRY_COMPLETE:
2242             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2243                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2244                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2245                 hci_emit_event(event, sizeof(event), 1);
2246             }
2247             break;
2248         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2249             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2250                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2251             }
2252             break;
2253         case HCI_EVENT_CONNECTION_REQUEST:
2254             reverse_bd_addr(&packet[2], addr);
2255             if (hci_stack->gap_classic_accept_callback != NULL){
2256                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2257                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2258                     bd_addr_copy(hci_stack->decline_addr, addr);
2259                     break;
2260                 }
2261             }
2262 
2263             // TODO: eval COD 8-10
2264             link_type = packet[11];
2265             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2266             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2267             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2268             if (!conn) {
2269                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2270             }
2271             if (!conn) {
2272                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2273                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2274                 bd_addr_copy(hci_stack->decline_addr, addr);
2275                 break;
2276             }
2277             conn->role  = HCI_ROLE_SLAVE;
2278             conn->state = RECEIVED_CONNECTION_REQUEST;
2279             // store info about eSCO
2280             if (link_type == 0x02){
2281                 conn->remote_supported_features[0] |= 1;
2282             }
2283             hci_run();
2284             break;
2285 
2286         case HCI_EVENT_CONNECTION_COMPLETE:
2287             // Connection management
2288             reverse_bd_addr(&packet[5], addr);
2289             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2290             addr_type = BD_ADDR_TYPE_ACL;
2291             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2292             if (conn) {
2293                 if (!packet[2]){
2294                     conn->state = OPEN;
2295                     conn->con_handle = little_endian_read_16(packet, 3);
2296 
2297                     // queue get remote feature
2298                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2299 
2300                     // queue set supervision timeout if we're master
2301                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2302                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2303                     }
2304 
2305                     // restart timer
2306                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2307                     btstack_run_loop_add_timer(&conn->timeout);
2308 
2309                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2310 
2311                     hci_emit_nr_connections_changed();
2312                 } else {
2313                     // connection failed
2314                     hci_handle_connection_failed(conn, packet[2]);
2315                 }
2316             }
2317             break;
2318 
2319         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2320             reverse_bd_addr(&packet[5], addr);
2321             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2322             if (packet[2]){
2323                 // connection failed
2324                 break;
2325             }
2326             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2327             if (!conn) {
2328                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2329             }
2330             if (!conn) {
2331                 break;
2332             }
2333             conn->state = OPEN;
2334             conn->con_handle = little_endian_read_16(packet, 3);
2335 
2336 #ifdef ENABLE_SCO_OVER_HCI
2337             // update SCO
2338             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2339                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2340             }
2341             // trigger can send now
2342             if (hci_have_usb_transport()){
2343                 hci_stack->sco_can_send_now = 1;
2344             }
2345 #endif
2346             break;
2347 
2348         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2349             handle = little_endian_read_16(packet, 3);
2350             conn = hci_connection_for_handle(handle);
2351             if (!conn) break;
2352             if (!packet[2]){
2353                 const uint8_t * features = &packet[5];
2354                 hci_handle_remote_features_page_0(conn, features);
2355 
2356                 // read extended features if possible
2357                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2358                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2359                     break;
2360                 }
2361             }
2362             hci_handle_remote_features_received(conn);
2363             break;
2364 
2365         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2366             handle = little_endian_read_16(packet, 3);
2367             conn = hci_connection_for_handle(handle);
2368             if (!conn) break;
2369             // status = ok, page = 1
2370             if (!packet[2]) {
2371                 uint8_t page_number = packet[5];
2372                 uint8_t maximum_page_number = packet[6];
2373                 const uint8_t * features = &packet[7];
2374                 bool done = false;
2375                 switch (page_number){
2376                     case 1:
2377                         hci_handle_remote_features_page_1(conn, features);
2378                         if (maximum_page_number >= 2){
2379                             // get Secure Connections (Controller) from Page 2 if available
2380                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2381                         } else {
2382                             // otherwise, assume SC (Controller) == SC (Host)
2383                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2384                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2385                             }
2386                             done = true;
2387                         }
2388                         break;
2389                     case 2:
2390                         hci_handle_remote_features_page_2(conn, features);
2391                         done = true;
2392                         break;
2393                     default:
2394                         break;
2395                 }
2396                 if (!done) break;
2397             }
2398             hci_handle_remote_features_received(conn);
2399             break;
2400 
2401         case HCI_EVENT_LINK_KEY_REQUEST:
2402             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2403             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2404             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2405             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2406             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2407             hci_run();
2408             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2409             return;
2410 
2411         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2412             reverse_bd_addr(&packet[2], addr);
2413             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2414             if (!conn) break;
2415             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2416             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2417             // Change Connection Encryption keeps link key type
2418             if (link_key_type != CHANGED_COMBINATION_KEY){
2419                 conn->link_key_type = link_key_type;
2420             }
2421             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2422             // still forward event to allow dismiss of pairing dialog
2423             break;
2424         }
2425 
2426         case HCI_EVENT_PIN_CODE_REQUEST:
2427             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2428             // non-bondable mode: pin code negative reply will be sent
2429             if (!hci_stack->bondable){
2430                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2431                 hci_run();
2432                 return;
2433             }
2434             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2435             if (!hci_stack->link_key_db) break;
2436             hci_event_pin_code_request_get_bd_addr(packet, addr);
2437             hci_stack->link_key_db->delete_link_key(addr);
2438             break;
2439 
2440         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2441             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2442             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2443             break;
2444 
2445         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2446             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2447             if (!hci_stack->ssp_auto_accept) break;
2448             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2449             break;
2450 
2451         case HCI_EVENT_USER_PASSKEY_REQUEST:
2452             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2453             if (!hci_stack->ssp_auto_accept) break;
2454             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2455             break;
2456         case HCI_EVENT_MODE_CHANGE:
2457             handle = hci_event_mode_change_get_handle(packet);
2458             conn = hci_connection_for_handle(handle);
2459             if (!conn) break;
2460             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2461             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2462             break;
2463 #endif
2464 
2465         case HCI_EVENT_ENCRYPTION_CHANGE:
2466             handle = hci_event_encryption_change_get_connection_handle(packet);
2467             conn = hci_connection_for_handle(handle);
2468             if (!conn) break;
2469             if (hci_event_encryption_change_get_status(packet) == 0u) {
2470                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2471                 if (encryption_enabled){
2472                     if (hci_is_le_connection(conn)){
2473                         // For LE, we accept connection as encrypted
2474                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2475                     }
2476 #ifdef ENABLE_CLASSIC
2477                     else {
2478                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2479                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2480                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2481                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2482                             log_info("SC during pairing, but only E0 now -> abort");
2483                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2484                             break;
2485                         }
2486 
2487                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2488                         if (connected_uses_aes_ccm){
2489                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2490                         }
2491 
2492                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2493                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2494                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2495                         } else {
2496                             // if not, pretend everything is perfect
2497                             hci_handle_read_encryption_key_size_complete(conn, 16);
2498                         }
2499                     }
2500 #endif
2501                 } else {
2502                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2503                 }
2504             }
2505 
2506             break;
2507 
2508 #ifdef ENABLE_CLASSIC
2509         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2510             handle = hci_event_authentication_complete_get_connection_handle(packet);
2511             conn = hci_connection_for_handle(handle);
2512             if (!conn) break;
2513 
2514             // ignore authentication event if we didn't request it
2515             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2516 
2517             // dedicated bonding: send result and disconnect
2518             if (conn->bonding_flags & BONDING_DEDICATED){
2519                 conn->bonding_flags &= ~BONDING_DEDICATED;
2520                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2521                 conn->bonding_status = packet[2];
2522                 break;
2523             }
2524 
2525             // authenticated only if auth status == 0
2526             if (hci_event_authentication_complete_get_status(packet) == 0){
2527                 // authenticated
2528                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2529 
2530                 // If link key sufficient for requested security and not already encrypted, start encryption
2531                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2532                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2533                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2534                     break;
2535                 }
2536             }
2537 
2538             // emit updated security level
2539             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2540             break;
2541 #endif
2542 
2543         // HCI_EVENT_DISCONNECTION_COMPLETE
2544         // has been split, to first notify stack before shutting connection down
2545         // see end of function, too.
2546         case HCI_EVENT_DISCONNECTION_COMPLETE:
2547             if (packet[2]) break;   // status != 0
2548             handle = little_endian_read_16(packet, 3);
2549             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2550             if (hci_stack->acl_fragmentation_total_size > 0u) {
2551                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2552                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2553                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2554                     hci_stack->acl_fragmentation_total_size = 0;
2555                     hci_stack->acl_fragmentation_pos = 0;
2556                     if (release_buffer){
2557                         hci_release_packet_buffer();
2558                     }
2559                 }
2560             }
2561 
2562             conn = hci_connection_for_handle(handle);
2563             if (!conn) break;
2564             // mark connection for shutdown
2565             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2566 
2567             // emit dedicatd bonding event
2568             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2569                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2570             }
2571 
2572 #ifdef ENABLE_BLE
2573 #ifdef ENABLE_LE_PERIPHERAL
2574             // re-enable advertisements for le connections if active
2575             if (hci_is_le_connection(conn)){
2576                 hci_update_advertisements_enabled_for_current_roles();
2577             }
2578 #endif
2579 #endif
2580             break;
2581 
2582         case HCI_EVENT_HARDWARE_ERROR:
2583             log_error("Hardware Error: 0x%02x", packet[2]);
2584             if (hci_stack->hardware_error_callback){
2585                 (*hci_stack->hardware_error_callback)(packet[2]);
2586             } else {
2587                 // if no special requests, just reboot stack
2588                 hci_power_control_off();
2589                 hci_power_control_on();
2590             }
2591             break;
2592 
2593 #ifdef ENABLE_CLASSIC
2594         case HCI_EVENT_ROLE_CHANGE:
2595             if (packet[2]) break;   // status != 0
2596             reverse_bd_addr(&packet[3], addr);
2597             addr_type = BD_ADDR_TYPE_ACL;
2598             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2599             if (!conn) break;
2600             conn->role = packet[9];
2601             break;
2602 #endif
2603 
2604         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2605             // release packet buffer only for asynchronous transport and if there are not further fragements
2606             if (hci_transport_synchronous()) {
2607                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2608                 return; // instead of break: to avoid re-entering hci_run()
2609             }
2610             hci_stack->acl_fragmentation_tx_active = 0;
2611             if (hci_stack->acl_fragmentation_total_size) break;
2612             hci_release_packet_buffer();
2613 
2614             // L2CAP receives this event via the hci_emit_event below
2615 
2616 #ifdef ENABLE_CLASSIC
2617             // For SCO, we do the can_send_now_check here
2618             hci_notify_if_sco_can_send_now();
2619 #endif
2620             break;
2621 
2622 #ifdef ENABLE_CLASSIC
2623         case HCI_EVENT_SCO_CAN_SEND_NOW:
2624             // For SCO, we do the can_send_now_check here
2625             hci_stack->sco_can_send_now = 1;
2626             hci_notify_if_sco_can_send_now();
2627             return;
2628 
2629         // explode inquriy results for easier consumption
2630         case HCI_EVENT_INQUIRY_RESULT:
2631         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2632         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2633             gap_inquiry_explode(packet, size);
2634             break;
2635 #endif
2636 
2637 #ifdef ENABLE_BLE
2638         case HCI_EVENT_LE_META:
2639             switch (packet[2]){
2640 #ifdef ENABLE_LE_CENTRAL
2641                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2642                     // log_info("advertising report received");
2643                     if (!hci_stack->le_scanning_enabled) break;
2644                     le_handle_advertisement_report(packet, size);
2645                     break;
2646 #endif
2647                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2648                     // Connection management
2649                     reverse_bd_addr(&packet[8], addr);
2650                     addr_type = (bd_addr_type_t)packet[7];
2651                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2652                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2653 
2654 #ifdef ENABLE_LE_CENTRAL
2655                     // handle error: error is reported only to the initiator -> outgoing connection
2656                     if (packet[3]){
2657 
2658                         // handle cancelled outgoing connection
2659                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2660                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2661                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2662                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2663                             // whitelist connect
2664                             if (hci_is_le_connection_type(addr_type)){
2665                                 hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2666                                 hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2667                             }
2668                             // get outgoing connection conn struct for direct connect
2669                             conn = gap_get_outgoing_connection();
2670                         }
2671 
2672                         // outgoing le connection establishment is done
2673                         if (conn){
2674                             // remove entry
2675                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2676                             btstack_memory_hci_connection_free( conn );
2677                         }
2678                         break;
2679                     }
2680 #endif
2681 
2682                     // on success, both hosts receive connection complete event
2683                     if (packet[6] == HCI_ROLE_MASTER){
2684 #ifdef ENABLE_LE_CENTRAL
2685                         // if we're master on an le connection, it was an outgoing connection and we're done with it
2686                         // note: no hci_connection_t object exists yet for connect with whitelist
2687                         if (hci_is_le_connection_type(addr_type)){
2688                             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2689                             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2690                         }
2691 #endif
2692                     } else {
2693 #ifdef ENABLE_LE_PERIPHERAL
2694                         // if we're slave, it was an incoming connection, advertisements have stopped
2695                         hci_stack->le_advertisements_active = 0;
2696 #endif
2697                     }
2698                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2699                     if (!conn){
2700                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2701                     }
2702                     // no memory, sorry.
2703                     if (!conn){
2704                         break;
2705                     }
2706 
2707                     conn->state = OPEN;
2708                     conn->role  = packet[6];
2709                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2710                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2711 
2712 #ifdef ENABLE_LE_PERIPHERAL
2713                     if (packet[6] == HCI_ROLE_SLAVE){
2714                         hci_update_advertisements_enabled_for_current_roles();
2715                     }
2716 #endif
2717 
2718                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2719 
2720                     // restart timer
2721                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2722                     // btstack_run_loop_add_timer(&conn->timeout);
2723 
2724                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2725 
2726                     hci_emit_nr_connections_changed();
2727                     break;
2728 
2729                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2730                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2731                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2732                     conn = hci_connection_for_handle(handle);
2733                     if (!conn) break;
2734                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2735                     break;
2736 
2737                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2738                     // connection
2739                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2740                     conn = hci_connection_for_handle(handle);
2741                     if (conn) {
2742                         // read arguments
2743                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2744                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2745                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2746                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2747 
2748                         // validate against current connection parameter range
2749                         le_connection_parameter_range_t existing_range;
2750                         gap_get_connection_parameter_range(&existing_range);
2751                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2752                         if (update_parameter){
2753                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2754                             conn->le_conn_interval_min = le_conn_interval_min;
2755                             conn->le_conn_interval_max = le_conn_interval_max;
2756                             conn->le_conn_latency = le_conn_latency;
2757                             conn->le_supervision_timeout = le_supervision_timeout;
2758                         } else {
2759                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2760                         }
2761                     }
2762                     break;
2763 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2764                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2765                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2766                     conn = hci_connection_for_handle(handle);
2767                     if (conn) {
2768                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2769                     }
2770                     break;
2771 #endif
2772                 default:
2773                     break;
2774             }
2775             break;
2776 #endif
2777         case HCI_EVENT_VENDOR_SPECIFIC:
2778             // Vendor specific commands often create vendor specific event instead of num completed packets
2779             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2780             switch (hci_stack->manufacturer){
2781                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2782                     hci_stack->num_cmd_packets = 1;
2783                     break;
2784                 default:
2785                     break;
2786             }
2787             break;
2788         default:
2789             break;
2790     }
2791 
2792     handle_event_for_current_stack_state(packet, size);
2793 
2794     // notify upper stack
2795 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2796 
2797     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2798     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2799         if (!packet[2]){
2800             handle = little_endian_read_16(packet, 3);
2801             hci_connection_t * aConn = hci_connection_for_handle(handle);
2802             if (aConn) {
2803                 // discard connection if app did not trigger a reconnect in the event handler
2804                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2805                     hci_shutdown_connection(aConn);
2806                 }
2807             }
2808         }
2809     }
2810 
2811 	// execute main loop
2812 	hci_run();
2813 }
2814 
2815 #ifdef ENABLE_CLASSIC
2816 
2817 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2818 static void sco_schedule_tx(hci_connection_t * conn);
2819 
2820 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2821     log_debug("SCO TX Timeout");
2822     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2823     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2824     if (!conn) return;
2825 
2826     // trigger send
2827     conn->sco_tx_ready = 1;
2828     // extra packet if CVSD but SCO buffer is too short
2829     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2830         conn->sco_tx_ready++;
2831     }
2832     hci_notify_if_sco_can_send_now();
2833 }
2834 
2835 
2836 #define SCO_TX_AFTER_RX_MS (6)
2837 
2838 static void sco_schedule_tx(hci_connection_t * conn){
2839 
2840     uint32_t now = btstack_run_loop_get_time_ms();
2841     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2842     int time_delta_ms = sco_tx_ms - now;
2843 
2844     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2845 
2846     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2847     btstack_run_loop_set_timer(timer, time_delta_ms);
2848     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2849     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2850     btstack_run_loop_add_timer(timer);
2851 }
2852 
2853 static void sco_handler(uint8_t * packet, uint16_t size){
2854     // lookup connection struct
2855     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2856     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2857     if (!conn) return;
2858 
2859     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2860     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2861         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2862             packet[2] = 0x3c;
2863             memmove(&packet[3], &packet[23], 63);
2864             size = 63;
2865         }
2866     }
2867 
2868     if (hci_have_usb_transport()){
2869         // Nothing to do
2870     } else {
2871         // 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);
2872         if (hci_stack->synchronous_flow_control_enabled == 0){
2873             uint32_t now = btstack_run_loop_get_time_ms();
2874 
2875             if (!conn->sco_rx_valid){
2876                 // ignore first 10 packets
2877                 conn->sco_rx_count++;
2878                 // log_debug("sco rx count %u", conn->sco_rx_count);
2879                 if (conn->sco_rx_count == 10) {
2880                     // use first timestamp as is and pretent it just started
2881                     conn->sco_rx_ms = now;
2882                     conn->sco_rx_valid = 1;
2883                     conn->sco_rx_count = 0;
2884                     sco_schedule_tx(conn);
2885                 }
2886             } else {
2887                 // track expected arrival timme
2888                 conn->sco_rx_count++;
2889                 conn->sco_rx_ms += 7;
2890                 int delta = (int32_t) (now - conn->sco_rx_ms);
2891                 if (delta > 0){
2892                     conn->sco_rx_ms++;
2893                 }
2894                 // log_debug("sco rx %u", conn->sco_rx_ms);
2895                 sco_schedule_tx(conn);
2896             }
2897         }
2898     }
2899     // deliver to app
2900     if (hci_stack->sco_packet_handler) {
2901         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2902     }
2903 
2904 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2905     conn->num_packets_completed++;
2906     hci_stack->host_completed_packets = 1;
2907     hci_run();
2908 #endif
2909 }
2910 #endif
2911 
2912 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2913     hci_dump_packet(packet_type, 1, packet, size);
2914     switch (packet_type) {
2915         case HCI_EVENT_PACKET:
2916             event_handler(packet, size);
2917             break;
2918         case HCI_ACL_DATA_PACKET:
2919             acl_handler(packet, size);
2920             break;
2921 #ifdef ENABLE_CLASSIC
2922         case HCI_SCO_DATA_PACKET:
2923             sco_handler(packet, size);
2924             break;
2925 #endif
2926         default:
2927             break;
2928     }
2929 }
2930 
2931 /**
2932  * @brief Add event packet handler.
2933  */
2934 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2935     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2936 }
2937 
2938 
2939 /** Register HCI packet handlers */
2940 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2941     hci_stack->acl_packet_handler = handler;
2942 }
2943 
2944 #ifdef ENABLE_CLASSIC
2945 /**
2946  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2947  */
2948 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2949     hci_stack->sco_packet_handler = handler;
2950 }
2951 #endif
2952 
2953 static void hci_state_reset(void){
2954     // no connections yet
2955     hci_stack->connections = NULL;
2956 
2957     // keep discoverable/connectable as this has been requested by the client(s)
2958     // hci_stack->discoverable = 0;
2959     // hci_stack->connectable = 0;
2960     // hci_stack->bondable = 1;
2961     // hci_stack->own_addr_type = 0;
2962 
2963     // buffer is free
2964     hci_stack->hci_packet_buffer_reserved = 0;
2965 
2966     // no pending cmds
2967     hci_stack->decline_reason = 0;
2968     hci_stack->new_scan_enable_value = 0xff;
2969 
2970     // LE
2971 #ifdef ENABLE_BLE
2972     memset(hci_stack->le_random_address, 0, 6);
2973     hci_stack->le_random_address_set = 0;
2974 #endif
2975 #ifdef ENABLE_LE_CENTRAL
2976     hci_stack->le_scanning_active  = 0;
2977     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2978     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2979     hci_stack->le_whitelist_capacity = 0;
2980 #endif
2981 }
2982 
2983 #ifdef ENABLE_CLASSIC
2984 /**
2985  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2986  */
2987 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2988     // store and open remote device db
2989     hci_stack->link_key_db = link_key_db;
2990     if (hci_stack->link_key_db) {
2991         hci_stack->link_key_db->open();
2992     }
2993 }
2994 #endif
2995 
2996 void hci_init(const hci_transport_t *transport, const void *config){
2997 
2998 #ifdef HAVE_MALLOC
2999     if (!hci_stack) {
3000         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3001     }
3002 #else
3003     hci_stack = &hci_stack_static;
3004 #endif
3005     memset(hci_stack, 0, sizeof(hci_stack_t));
3006 
3007     // reference to use transport layer implementation
3008     hci_stack->hci_transport = transport;
3009 
3010     // reference to used config
3011     hci_stack->config = config;
3012 
3013     // setup pointer for outgoing packet buffer
3014     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3015 
3016     // max acl payload size defined in config.h
3017     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3018 
3019     // register packet handlers with transport
3020     transport->register_packet_handler(&packet_handler);
3021 
3022     hci_stack->state = HCI_STATE_OFF;
3023 
3024     // class of device
3025     hci_stack->class_of_device = 0x007a020c; // Smartphone
3026 
3027     // bondable by default
3028     hci_stack->bondable = 1;
3029 
3030 #ifdef ENABLE_CLASSIC
3031     // classic name
3032     hci_stack->local_name = default_classic_name;
3033 
3034     // Master slave policy
3035     hci_stack->master_slave_policy = 1;
3036 
3037     // Allow Role Switch
3038     hci_stack->allow_role_switch = 1;
3039 
3040     // Default / minimum security level = 2
3041     hci_stack->gap_security_level = LEVEL_2;
3042 
3043     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3044     hci_stack->gap_required_encyrption_key_size = 7;
3045 #endif
3046 
3047     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3048     hci_stack->ssp_enable = 1;
3049     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3050     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3051     hci_stack->ssp_auto_accept = 1;
3052 
3053     // Secure Connections: enable (requires support from Controller)
3054     hci_stack->secure_connections_enable = true;
3055 
3056     // voice setting - signed 16 bit pcm data with CVSD over the air
3057     hci_stack->sco_voice_setting = 0x60;
3058 
3059 #ifdef ENABLE_LE_CENTRAL
3060     // connection parameter to use for outgoing connections
3061     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3062     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3063     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3064     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3065     hci_stack->le_connection_latency      = 4;         // 4
3066     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3067     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3068     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3069 
3070     // default LE Scanning
3071     hci_stack->le_scan_type     =   0x1; // active
3072     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3073     hci_stack->le_scan_window   =  0x30; //  30 ms
3074 #endif
3075 
3076 #ifdef ENABLE_LE_PERIPHERAL
3077     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3078 #endif
3079 
3080     // connection parameter range used to answer connection parameter update requests in l2cap
3081     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3082     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3083     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3084     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3085     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3086     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3087 
3088     hci_state_reset();
3089 }
3090 
3091 /**
3092  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3093  */
3094 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3095     hci_stack->chipset = chipset_driver;
3096 
3097     // reset chipset driver - init is also called on power_up
3098     if (hci_stack->chipset && hci_stack->chipset->init){
3099         hci_stack->chipset->init(hci_stack->config);
3100     }
3101 }
3102 
3103 /**
3104  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3105  */
3106 void hci_set_control(const btstack_control_t *hardware_control){
3107     // references to used control implementation
3108     hci_stack->control = hardware_control;
3109     // init with transport config
3110     hardware_control->init(hci_stack->config);
3111 }
3112 
3113 void hci_close(void){
3114     // close remote device db
3115     if (hci_stack->link_key_db) {
3116         hci_stack->link_key_db->close();
3117     }
3118 
3119     btstack_linked_list_iterator_t lit;
3120     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3121     while (btstack_linked_list_iterator_has_next(&lit)){
3122         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3123         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3124         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3125         hci_shutdown_connection(connection);
3126     }
3127 
3128     hci_power_control(HCI_POWER_OFF);
3129 
3130 #ifdef HAVE_MALLOC
3131     free(hci_stack);
3132 #endif
3133     hci_stack = NULL;
3134 }
3135 
3136 #ifdef ENABLE_CLASSIC
3137 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3138     // validate ranage and set
3139     if (encryption_key_size < 7)  return;
3140     if (encryption_key_size > 16) return;
3141     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3142 }
3143 
3144 void gap_set_security_level(gap_security_level_t security_level){
3145     hci_stack->gap_security_level = security_level;
3146 }
3147 
3148 gap_security_level_t gap_get_security_level(void){
3149     return hci_stack->gap_security_level;
3150 }
3151 #endif
3152 
3153 #ifdef ENABLE_CLASSIC
3154 void gap_set_class_of_device(uint32_t class_of_device){
3155     hci_stack->class_of_device = class_of_device;
3156 }
3157 
3158 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3159     hci_stack->default_link_policy_settings = default_link_policy_settings;
3160 }
3161 
3162 void gap_set_allow_role_switch(bool allow_role_switch){
3163     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3164 }
3165 
3166 uint8_t hci_get_allow_role_switch(void){
3167     return  hci_stack->allow_role_switch;
3168 }
3169 
3170 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3171     hci_stack->link_supervision_timeout = link_supervision_timeout;
3172 }
3173 
3174 void hci_disable_l2cap_timeout_check(void){
3175     disable_l2cap_timeouts = 1;
3176 }
3177 #endif
3178 
3179 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3180 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3181 void hci_set_bd_addr(bd_addr_t addr){
3182     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3183     hci_stack->custom_bd_addr_set = 1;
3184 }
3185 #endif
3186 
3187 // State-Module-Driver overview
3188 // state                    module  low-level
3189 // HCI_STATE_OFF             off      close
3190 // HCI_STATE_INITIALIZING,   on       open
3191 // HCI_STATE_WORKING,        on       open
3192 // HCI_STATE_HALTING,        on       open
3193 // HCI_STATE_SLEEPING,    off/sleep   close
3194 // HCI_STATE_FALLING_ASLEEP  on       open
3195 
3196 static int hci_power_control_on(void){
3197 
3198     // power on
3199     int err = 0;
3200     if (hci_stack->control && hci_stack->control->on){
3201         err = (*hci_stack->control->on)();
3202     }
3203     if (err){
3204         log_error( "POWER_ON failed");
3205         hci_emit_hci_open_failed();
3206         return err;
3207     }
3208 
3209     // int chipset driver
3210     if (hci_stack->chipset && hci_stack->chipset->init){
3211         hci_stack->chipset->init(hci_stack->config);
3212     }
3213 
3214     // init transport
3215     if (hci_stack->hci_transport->init){
3216         hci_stack->hci_transport->init(hci_stack->config);
3217     }
3218 
3219     // open transport
3220     err = hci_stack->hci_transport->open();
3221     if (err){
3222         log_error( "HCI_INIT failed, turning Bluetooth off again");
3223         if (hci_stack->control && hci_stack->control->off){
3224             (*hci_stack->control->off)();
3225         }
3226         hci_emit_hci_open_failed();
3227         return err;
3228     }
3229     return 0;
3230 }
3231 
3232 static void hci_power_control_off(void){
3233 
3234     log_info("hci_power_control_off");
3235 
3236     // close low-level device
3237     hci_stack->hci_transport->close();
3238 
3239     log_info("hci_power_control_off - hci_transport closed");
3240 
3241     // power off
3242     if (hci_stack->control && hci_stack->control->off){
3243         (*hci_stack->control->off)();
3244     }
3245 
3246     log_info("hci_power_control_off - control closed");
3247 
3248     hci_stack->state = HCI_STATE_OFF;
3249 }
3250 
3251 static void hci_power_control_sleep(void){
3252 
3253     log_info("hci_power_control_sleep");
3254 
3255 #if 0
3256     // don't close serial port during sleep
3257 
3258     // close low-level device
3259     hci_stack->hci_transport->close(hci_stack->config);
3260 #endif
3261 
3262     // sleep mode
3263     if (hci_stack->control && hci_stack->control->sleep){
3264         (*hci_stack->control->sleep)();
3265     }
3266 
3267     hci_stack->state = HCI_STATE_SLEEPING;
3268 }
3269 
3270 static int hci_power_control_wake(void){
3271 
3272     log_info("hci_power_control_wake");
3273 
3274     // wake on
3275     if (hci_stack->control && hci_stack->control->wake){
3276         (*hci_stack->control->wake)();
3277     }
3278 
3279 #if 0
3280     // open low-level device
3281     int err = hci_stack->hci_transport->open(hci_stack->config);
3282     if (err){
3283         log_error( "HCI_INIT failed, turning Bluetooth off again");
3284         if (hci_stack->control && hci_stack->control->off){
3285             (*hci_stack->control->off)();
3286         }
3287         hci_emit_hci_open_failed();
3288         return err;
3289     }
3290 #endif
3291 
3292     return 0;
3293 }
3294 
3295 static void hci_power_transition_to_initializing(void){
3296     // set up state machine
3297     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3298     hci_stack->hci_packet_buffer_reserved = 0;
3299     hci_stack->state = HCI_STATE_INITIALIZING;
3300     hci_stack->substate = HCI_INIT_SEND_RESET;
3301 }
3302 
3303 int hci_power_control(HCI_POWER_MODE power_mode){
3304 
3305     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3306 
3307     int err = 0;
3308     switch (hci_stack->state){
3309 
3310         case HCI_STATE_OFF:
3311             switch (power_mode){
3312                 case HCI_POWER_ON:
3313                     err = hci_power_control_on();
3314                     if (err) {
3315                         log_error("hci_power_control_on() error %d", err);
3316                         return err;
3317                     }
3318                     hci_power_transition_to_initializing();
3319                     break;
3320                 case HCI_POWER_OFF:
3321                     // do nothing
3322                     break;
3323                 case HCI_POWER_SLEEP:
3324                     // do nothing (with SLEEP == OFF)
3325                     break;
3326             }
3327             break;
3328 
3329         case HCI_STATE_INITIALIZING:
3330             switch (power_mode){
3331                 case HCI_POWER_ON:
3332                     // do nothing
3333                     break;
3334                 case HCI_POWER_OFF:
3335                     // no connections yet, just turn it off
3336                     hci_power_control_off();
3337                     break;
3338                 case HCI_POWER_SLEEP:
3339                     // no connections yet, just turn it off
3340                     hci_power_control_sleep();
3341                     break;
3342             }
3343             break;
3344 
3345         case HCI_STATE_WORKING:
3346             switch (power_mode){
3347                 case HCI_POWER_ON:
3348                     // do nothing
3349                     break;
3350                 case HCI_POWER_OFF:
3351                     // see hci_run
3352                     hci_stack->state = HCI_STATE_HALTING;
3353                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3354                     break;
3355                 case HCI_POWER_SLEEP:
3356                     // see hci_run
3357                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3358                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3359                     break;
3360             }
3361             break;
3362 
3363         case HCI_STATE_HALTING:
3364             switch (power_mode){
3365                 case HCI_POWER_ON:
3366                     hci_power_transition_to_initializing();
3367                     break;
3368                 case HCI_POWER_OFF:
3369                     // do nothing
3370                     break;
3371                 case HCI_POWER_SLEEP:
3372                     // see hci_run
3373                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3374                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3375                     break;
3376             }
3377             break;
3378 
3379         case HCI_STATE_FALLING_ASLEEP:
3380             switch (power_mode){
3381                 case HCI_POWER_ON:
3382 
3383 #ifdef HAVE_PLATFORM_IPHONE_OS
3384                     // nothing to do, if H4 supports power management
3385                     if (btstack_control_iphone_power_management_enabled()){
3386                         hci_stack->state = HCI_STATE_INITIALIZING;
3387                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3388                         break;
3389                     }
3390 #endif
3391                     hci_power_transition_to_initializing();
3392                     break;
3393                 case HCI_POWER_OFF:
3394                     // see hci_run
3395                     hci_stack->state = HCI_STATE_HALTING;
3396                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3397                     break;
3398                 case HCI_POWER_SLEEP:
3399                     // do nothing
3400                     break;
3401             }
3402             break;
3403 
3404         case HCI_STATE_SLEEPING:
3405             switch (power_mode){
3406                 case HCI_POWER_ON:
3407 
3408 #ifdef HAVE_PLATFORM_IPHONE_OS
3409                     // nothing to do, if H4 supports power management
3410                     if (btstack_control_iphone_power_management_enabled()){
3411                         hci_stack->state = HCI_STATE_INITIALIZING;
3412                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3413                         hci_update_scan_enable();
3414                         break;
3415                     }
3416 #endif
3417                     err = hci_power_control_wake();
3418                     if (err) return err;
3419                     hci_power_transition_to_initializing();
3420                     break;
3421                 case HCI_POWER_OFF:
3422                     hci_stack->state = HCI_STATE_HALTING;
3423                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3424                     break;
3425                 case HCI_POWER_SLEEP:
3426                     // do nothing
3427                     break;
3428             }
3429             break;
3430     }
3431 
3432     // create internal event
3433 	hci_emit_state();
3434 
3435 	// trigger next/first action
3436 	hci_run();
3437 
3438     return 0;
3439 }
3440 
3441 
3442 #ifdef ENABLE_CLASSIC
3443 
3444 static void hci_update_scan_enable(void){
3445     // 2 = page scan, 1 = inq scan
3446     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3447     hci_run();
3448 }
3449 
3450 void gap_discoverable_control(uint8_t enable){
3451     if (enable) enable = 1; // normalize argument
3452 
3453     if (hci_stack->discoverable == enable){
3454         hci_emit_discoverable_enabled(hci_stack->discoverable);
3455         return;
3456     }
3457 
3458     hci_stack->discoverable = enable;
3459     hci_update_scan_enable();
3460 }
3461 
3462 void gap_connectable_control(uint8_t enable){
3463     if (enable) enable = 1; // normalize argument
3464 
3465     // don't emit event
3466     if (hci_stack->connectable == enable) return;
3467 
3468     hci_stack->connectable = enable;
3469     hci_update_scan_enable();
3470 }
3471 #endif
3472 
3473 void gap_local_bd_addr(bd_addr_t address_buffer){
3474     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3475 }
3476 
3477 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3478 static void hci_host_num_completed_packets(void){
3479 
3480     // create packet manually as arrays are not supported and num_commands should not get reduced
3481     hci_reserve_packet_buffer();
3482     uint8_t * packet = hci_get_outgoing_packet_buffer();
3483 
3484     uint16_t size = 0;
3485     uint16_t num_handles = 0;
3486     packet[size++] = 0x35;
3487     packet[size++] = 0x0c;
3488     size++;  // skip param len
3489     size++;  // skip num handles
3490 
3491     // add { handle, packets } entries
3492     btstack_linked_item_t * it;
3493     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3494         hci_connection_t * connection = (hci_connection_t *) it;
3495         if (connection->num_packets_completed){
3496             little_endian_store_16(packet, size, connection->con_handle);
3497             size += 2;
3498             little_endian_store_16(packet, size, connection->num_packets_completed);
3499             size += 2;
3500             //
3501             num_handles++;
3502             connection->num_packets_completed = 0;
3503         }
3504     }
3505 
3506     packet[2] = size - 3;
3507     packet[3] = num_handles;
3508 
3509     hci_stack->host_completed_packets = 0;
3510 
3511     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3512     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3513 
3514     // release packet buffer for synchronous transport implementations
3515     if (hci_transport_synchronous()){
3516         hci_release_packet_buffer();
3517         hci_emit_transport_packet_sent();
3518     }
3519 }
3520 #endif
3521 
3522 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3523     UNUSED(ds);
3524     hci_stack->substate = HCI_HALTING_CLOSE;
3525     // allow packet handlers to defer final shutdown
3526     hci_emit_state();
3527     hci_run();
3528 }
3529 
3530 static bool hci_run_acl_fragments(void){
3531     if (hci_stack->acl_fragmentation_total_size > 0u) {
3532         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3533         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3534         if (connection) {
3535             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3536                 hci_send_acl_packet_fragments(connection);
3537                 return true;
3538             }
3539         } else {
3540             // connection gone -> discard further fragments
3541             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3542             hci_stack->acl_fragmentation_total_size = 0;
3543             hci_stack->acl_fragmentation_pos = 0;
3544         }
3545     }
3546     return false;
3547 }
3548 
3549 #ifdef ENABLE_CLASSIC
3550 static bool hci_run_general_gap_classic(void){
3551 
3552     // decline incoming connections
3553     if (hci_stack->decline_reason){
3554         uint8_t reason = hci_stack->decline_reason;
3555         hci_stack->decline_reason = 0;
3556         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3557         return true;
3558     }
3559     // send scan enable
3560     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3561         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3562         hci_stack->new_scan_enable_value = 0xff;
3563         return true;
3564     }
3565     // start/stop inquiry
3566     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3567         uint8_t duration = hci_stack->inquiry_state;
3568         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3569         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3570         return true;
3571     }
3572     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3573         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3574         hci_send_cmd(&hci_inquiry_cancel);
3575         return true;
3576     }
3577     // remote name request
3578     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3579         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3580         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3581                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3582         return true;
3583     }
3584     // pairing
3585     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3586         uint8_t state = hci_stack->gap_pairing_state;
3587         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3588         switch (state){
3589             case GAP_PAIRING_STATE_SEND_PIN:
3590                 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);
3591                 break;
3592             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3593                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3594                 break;
3595             case GAP_PAIRING_STATE_SEND_PASSKEY:
3596                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3597                 break;
3598             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3599                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3600                 break;
3601             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3602                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3603                 break;
3604             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3605                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3606                 break;
3607             default:
3608                 break;
3609         }
3610         return true;
3611     }
3612     return false;
3613 }
3614 #endif
3615 
3616 #ifdef ENABLE_BLE
3617 static bool hci_run_general_gap_le(void){
3618 
3619     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3620 
3621     if (hci_stack->state != HCI_STATE_WORKING) return false;
3622     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3623 
3624     // check if whitelist needs modification
3625     bool whitelist_modification_pending = false;
3626     btstack_linked_list_iterator_t lit;
3627     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3628     while (btstack_linked_list_iterator_has_next(&lit)){
3629         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3630         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3631             whitelist_modification_pending = true;
3632             break;
3633         }
3634     }
3635 
3636 #ifdef ENABLE_LE_CENTRAL
3637     // scanning control
3638     bool scanning_stop = false;
3639     if (hci_stack->le_scanning_active) {
3640         // stop if:
3641         // - parameter change required
3642         // - it's disabled
3643         // - whitelist change required but used for scanning
3644         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3645         if ((hci_stack->le_scanning_param_update) || !hci_stack->le_scanning_enabled || scanning_uses_whitelist){
3646             scanning_stop = true;
3647         }
3648     }
3649 
3650     if (scanning_stop){
3651         hci_stack->le_scanning_active = 0;
3652         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3653         return true;
3654     }
3655 
3656     if (hci_stack->le_scanning_param_update){
3657         hci_stack->le_scanning_param_update = false;
3658         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3659                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3660         return true;
3661     }
3662 #endif
3663 
3664 #ifdef ENABLE_LE_CENTRAL
3665     // connecting control
3666     bool connecting_stop = false;
3667     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3668         // stop connecting if:
3669         // - connecting uses white and whitelist modification pending
3670         // - if it got disabled
3671         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3672         if ((connecting_uses_whitelist && whitelist_modification_pending) || (hci_stack->le_connecting_request == LE_CONNECTING_IDLE)) {
3673             connecting_stop = true;
3674         }
3675     }
3676 
3677     if (connecting_stop){
3678         if (hci_stack->le_connecting_state != LE_CONNECTING_CANCEL){
3679             hci_send_cmd(&hci_le_create_connection_cancel);
3680             return true;
3681         }
3682     }
3683 #endif
3684 
3685 #ifdef ENABLE_LE_PERIPHERAL
3686     // le advertisement control
3687     bool advertising_stop = false;
3688     if (hci_stack->le_advertisements_active){
3689         // stop if:
3690         // - parameter change required
3691         // - it's disabled
3692         // - whitelist change required but used for scanning
3693         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3694         if ((hci_stack->le_advertisements_todo != 0) || !hci_stack->le_advertisements_enabled_for_current_roles || advertising_uses_whitelist) {
3695             advertising_stop = true;
3696         }
3697     }
3698 
3699     if (advertising_stop){
3700         hci_stack->le_advertisements_active = 0;
3701         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3702         return true;
3703     }
3704 
3705     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3706         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3707         hci_send_cmd(&hci_le_set_advertising_parameters,
3708                      hci_stack->le_advertisements_interval_min,
3709                      hci_stack->le_advertisements_interval_max,
3710                      hci_stack->le_advertisements_type,
3711                      hci_stack->le_own_addr_type,
3712                      hci_stack->le_advertisements_direct_address_type,
3713                      hci_stack->le_advertisements_direct_address,
3714                      hci_stack->le_advertisements_channel_map,
3715                      hci_stack->le_advertisements_filter_policy);
3716         return true;
3717     }
3718     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3719         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3720         uint8_t adv_data_clean[31];
3721         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3722         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3723                      hci_stack->le_advertisements_data_len);
3724         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3725         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3726         return true;
3727     }
3728     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3729         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3730         uint8_t scan_data_clean[31];
3731         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3732         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3733                      hci_stack->le_scan_response_data_len);
3734         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3735         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3736         return true;
3737     }
3738 #endif
3739 
3740     // LE Whitelist Management
3741     bool cancel_active = false;
3742 
3743 #ifdef ENABLE_LE_CENTRAL
3744     // if connect with whitelist is active, it will be cancelled, but we still get here until it is stopped
3745     cancel_active = hci_stack->le_connecting_state == LE_CONNECTING_CANCEL;
3746 #endif
3747 
3748     if (whitelist_modification_pending && !cancel_active){
3749         // add/remove entries
3750         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3751         while (btstack_linked_list_iterator_has_next(&lit)){
3752             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3753             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3754                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3755                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3756                 return true;
3757             }
3758             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3759                 bd_addr_t address;
3760                 bd_addr_type_t address_type = entry->address_type;
3761                 (void)memcpy(address, entry->address, 6);
3762                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3763                 btstack_memory_whitelist_entry_free(entry);
3764                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3765                 return true;
3766             }
3767         }
3768     }
3769 
3770 #ifdef ENABLE_LE_PERIPHERAL
3771     // re-start advertising
3772     if (hci_stack->le_advertisements_enabled_for_current_roles && (hci_stack->le_advertisements_active == 0)){
3773         // check if advertisements should be enabled given
3774         hci_stack->le_advertisements_active = 1;
3775         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3776         return true;
3777     }
3778 #endif
3779 
3780 #ifdef ENABLE_LE_CENTRAL
3781     // re-start scanning
3782     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3783         hci_stack->le_scanning_active = true;
3784         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3785         return true;
3786     }
3787 #endif
3788 
3789 #ifdef ENABLE_LE_CENTRAL
3790     // re-start connecting
3791     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3792         bd_addr_t null_addr;
3793         memset(null_addr, 0, 6);
3794         hci_send_cmd(&hci_le_create_connection,
3795                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3796                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3797                      1,         // use whitelist
3798                      0,         // peer address type
3799                      null_addr, // peer bd addr
3800                      hci_stack->le_own_addr_type, // our addr type:
3801                      hci_stack->le_connection_interval_min,    // conn interval min
3802                      hci_stack->le_connection_interval_max,    // conn interval max
3803                      hci_stack->le_connection_latency,         // conn latency
3804                      hci_stack->le_supervision_timeout,        // conn latency
3805                      hci_stack->le_minimum_ce_length,          // min ce length
3806                      hci_stack->le_maximum_ce_length           // max ce length
3807         );
3808         return true;
3809     }
3810 #endif
3811     return false;
3812 }
3813 #endif
3814 
3815 static bool hci_run_general_pending_commands(void){
3816     btstack_linked_item_t * it;
3817     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3818         hci_connection_t * connection = (hci_connection_t *) it;
3819 
3820         switch(connection->state){
3821             case SEND_CREATE_CONNECTION:
3822                 switch(connection->address_type){
3823 #ifdef ENABLE_CLASSIC
3824                     case BD_ADDR_TYPE_ACL:
3825                         log_info("sending hci_create_connection");
3826                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3827                         break;
3828 #endif
3829                     default:
3830 #ifdef ENABLE_BLE
3831 #ifdef ENABLE_LE_CENTRAL
3832                         log_info("sending hci_le_create_connection");
3833                         hci_send_cmd(&hci_le_create_connection,
3834                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3835                                      hci_stack->le_connection_scan_window,      // conn scan windows
3836                                      0,         // don't use whitelist
3837                                      connection->address_type, // peer address type
3838                                      connection->address,      // peer bd addr
3839                                      hci_stack->le_own_addr_type, // our addr type:
3840                                      hci_stack->le_connection_interval_min,    // conn interval min
3841                                      hci_stack->le_connection_interval_max,    // conn interval max
3842                                      hci_stack->le_connection_latency,         // conn latency
3843                                      hci_stack->le_supervision_timeout,        // conn latency
3844                                      hci_stack->le_minimum_ce_length,          // min ce length
3845                                      hci_stack->le_maximum_ce_length          // max ce length
3846                         );
3847                         connection->state = SENT_CREATE_CONNECTION;
3848 #endif
3849 #endif
3850                         break;
3851                 }
3852                 return true;
3853 
3854 #ifdef ENABLE_CLASSIC
3855             case RECEIVED_CONNECTION_REQUEST:
3856                 connection->role  = HCI_ROLE_SLAVE;
3857                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3858                     log_info("sending hci_accept_connection_request");
3859                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3860                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3861                 }
3862                 return true;
3863 #endif
3864 
3865 #ifdef ENABLE_BLE
3866 #ifdef ENABLE_LE_CENTRAL
3867             case SEND_CANCEL_CONNECTION:
3868                 connection->state = SENT_CANCEL_CONNECTION;
3869                 hci_send_cmd(&hci_le_create_connection_cancel);
3870                 return true;
3871 #endif
3872 #endif
3873             case SEND_DISCONNECT:
3874                 connection->state = SENT_DISCONNECT;
3875                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3876                 return true;
3877 
3878             default:
3879                 break;
3880         }
3881 
3882         // no further commands if connection is about to get shut down
3883         if (connection->state == SENT_DISCONNECT) continue;
3884 
3885         if (connection->authentication_flags & READ_RSSI){
3886             connectionClearAuthenticationFlags(connection, READ_RSSI);
3887             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3888             return true;
3889         }
3890 
3891 #ifdef ENABLE_CLASSIC
3892 
3893         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3894             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3895             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3896             return true;
3897         }
3898 
3899         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3900             log_info("responding to link key request");
3901             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3902 
3903             link_key_t link_key;
3904             link_key_type_t link_key_type;
3905             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
3906 
3907             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
3908             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
3909             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
3910             if (sc_downgrade){
3911                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
3912                 connection->state = SENT_DISCONNECT;
3913                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3914                 return true;
3915             }
3916 
3917             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
3918             if (have_link_key && security_level_sufficient){
3919                 connection->link_key_type = link_key_type;
3920                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3921             } else {
3922                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3923             }
3924             return true;
3925         }
3926 
3927         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3928             log_info("denying to pin request");
3929             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3930             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3931             return true;
3932         }
3933 
3934         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3935             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3936             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3937             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3938                 // tweak authentication requirements
3939                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3940                 if (connection->bonding_flags & BONDING_DEDICATED){
3941                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3942                 }
3943                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3944                     authreq |= 1;
3945                 }
3946                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3947             } else {
3948                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3949             }
3950             return true;
3951         }
3952 
3953         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3954             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3955             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3956             return true;
3957         }
3958 
3959         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3960             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3961             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3962             return true;
3963         }
3964 
3965         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3966             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3967             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3968             return true;
3969         }
3970 
3971         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3972             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3973             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3974             return true;
3975         }
3976 
3977         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
3978             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
3979             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
3980             return true;
3981         }
3982 
3983         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3984             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3985             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3986             connection->state = SENT_DISCONNECT;
3987             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3988             return true;
3989         }
3990 
3991         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3992             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3993             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
3994             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3995             return true;
3996         }
3997 
3998         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3999             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4000             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4001             return true;
4002         }
4003         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4004             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4005             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4006             return true;
4007         }
4008 #endif
4009 
4010         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4011             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4012             if (connection->state != SENT_DISCONNECT){
4013                 connection->state = SENT_DISCONNECT;
4014                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4015                 return true;
4016             }
4017         }
4018 
4019 #ifdef ENABLE_CLASSIC
4020         uint16_t sniff_min_interval;
4021         switch (connection->sniff_min_interval){
4022             case 0:
4023                 break;
4024             case 0xffff:
4025                 connection->sniff_min_interval = 0;
4026                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4027                 return true;
4028             default:
4029                 sniff_min_interval = connection->sniff_min_interval;
4030                 connection->sniff_min_interval = 0;
4031                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4032                 return true;
4033         }
4034 
4035         if (connection->request_role != HCI_ROLE_INVALID){
4036             hci_role_t  role = connection->request_role;
4037             connection->request_role = HCI_ROLE_INVALID;
4038             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4039             return true;
4040         }
4041 #endif
4042 
4043 #ifdef ENABLE_BLE
4044         switch (connection->le_con_parameter_update_state){
4045             // response to L2CAP CON PARAMETER UPDATE REQUEST
4046             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4047                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4048                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4049                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4050                              0x0000, 0xffff);
4051                 return true;
4052             case CON_PARAMETER_UPDATE_REPLY:
4053                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4054                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4055                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4056                              0x0000, 0xffff);
4057                 return true;
4058             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4059                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4060                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4061                 return true;
4062             default:
4063                 break;
4064         }
4065         if (connection->le_phy_update_all_phys != 0xffu){
4066             uint8_t all_phys = connection->le_phy_update_all_phys;
4067             connection->le_phy_update_all_phys = 0xff;
4068             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);
4069             return true;
4070         }
4071 #endif
4072     }
4073     return false;
4074 }
4075 
4076 static void hci_run(void){
4077 
4078     bool done;
4079 
4080     // send continuation fragments first, as they block the prepared packet buffer
4081     done = hci_run_acl_fragments();
4082     if (done) return;
4083 
4084 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4085     // send host num completed packets next as they don't require num_cmd_packets > 0
4086     if (!hci_can_send_comand_packet_transport()) return;
4087     if (hci_stack->host_completed_packets){
4088         hci_host_num_completed_packets();
4089         return;
4090     }
4091 #endif
4092 
4093     if (!hci_can_send_command_packet_now()) return;
4094 
4095     // global/non-connection oriented commands
4096 
4097 
4098 #ifdef ENABLE_CLASSIC
4099     // general gap classic
4100     done = hci_run_general_gap_classic();
4101     if (done) return;
4102 #endif
4103 
4104 #ifdef ENABLE_BLE
4105     // general gap le
4106     done = hci_run_general_gap_le();
4107     if (done) return;
4108 #endif
4109 
4110     // send pending HCI commands
4111     done = hci_run_general_pending_commands();
4112     if (done) return;
4113 
4114     // stack state sub statemachines
4115     hci_connection_t * connection;
4116     switch (hci_stack->state){
4117         case HCI_STATE_INITIALIZING:
4118             hci_initializing_run();
4119             break;
4120 
4121         case HCI_STATE_HALTING:
4122 
4123             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4124             switch (hci_stack->substate){
4125                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4126                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4127 
4128 #ifdef ENABLE_BLE
4129 #ifdef ENABLE_LE_CENTRAL
4130                     // free whitelist entries
4131                     {
4132                         btstack_linked_list_iterator_t lit;
4133                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4134                         while (btstack_linked_list_iterator_has_next(&lit)){
4135                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4136                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4137                             btstack_memory_whitelist_entry_free(entry);
4138                         }
4139                     }
4140 #endif
4141 #endif
4142                     // close all open connections
4143                     connection =  (hci_connection_t *) hci_stack->connections;
4144                     if (connection){
4145                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4146                         if (!hci_can_send_command_packet_now()) return;
4147 
4148                         // check state
4149                         if (connection->state == SENT_DISCONNECT) return;
4150                         connection->state = SENT_DISCONNECT;
4151 
4152                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4153 
4154                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4155                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4156 
4157                         // ... which would be ignored anyway as we shutdown (free) the connection now
4158                         hci_shutdown_connection(connection);
4159 
4160                         // finally, send the disconnect command
4161                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4162                         return;
4163                     }
4164 
4165                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4166                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4167                         log_info("HCI_STATE_HALTING: wait 50 ms");
4168                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4169                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4170                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4171                         btstack_run_loop_add_timer(&hci_stack->timeout);
4172                         break;
4173                     }
4174 
4175                     /* fall through */
4176 
4177                 case HCI_HALTING_CLOSE:
4178                     log_info("HCI_STATE_HALTING, calling off");
4179 
4180                     // switch mode
4181                     hci_power_control_off();
4182 
4183                     log_info("HCI_STATE_HALTING, emitting state");
4184                     hci_emit_state();
4185                     log_info("HCI_STATE_HALTING, done");
4186                     break;
4187 
4188                 case HCI_HALTING_W4_TIMER:
4189                     // keep waiting
4190 
4191                     break;
4192                 default:
4193                     break;
4194             }
4195 
4196             break;
4197 
4198         case HCI_STATE_FALLING_ASLEEP:
4199             switch(hci_stack->substate) {
4200                 case HCI_FALLING_ASLEEP_DISCONNECT:
4201                     log_info("HCI_STATE_FALLING_ASLEEP");
4202                     // close all open connections
4203                     connection =  (hci_connection_t *) hci_stack->connections;
4204 
4205 #ifdef HAVE_PLATFORM_IPHONE_OS
4206                     // don't close connections, if H4 supports power management
4207                     if (btstack_control_iphone_power_management_enabled()){
4208                         connection = NULL;
4209                     }
4210 #endif
4211                     if (connection){
4212 
4213                         // send disconnect
4214                         if (!hci_can_send_command_packet_now()) return;
4215 
4216                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4217                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4218 
4219                         // send disconnected event right away - causes higher layer connections to get closed, too.
4220                         hci_shutdown_connection(connection);
4221                         return;
4222                     }
4223 
4224                     if (hci_classic_supported()){
4225                         // disable page and inquiry scan
4226                         if (!hci_can_send_command_packet_now()) return;
4227 
4228                         log_info("HCI_STATE_HALTING, disabling inq scans");
4229                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4230 
4231                         // continue in next sub state
4232                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4233                         break;
4234                     }
4235 
4236                     /* fall through */
4237 
4238                 case HCI_FALLING_ASLEEP_COMPLETE:
4239                     log_info("HCI_STATE_HALTING, calling sleep");
4240 #ifdef HAVE_PLATFORM_IPHONE_OS
4241                     // don't actually go to sleep, if H4 supports power management
4242                     if (btstack_control_iphone_power_management_enabled()){
4243                         // SLEEP MODE reached
4244                         hci_stack->state = HCI_STATE_SLEEPING;
4245                         hci_emit_state();
4246                         break;
4247                     }
4248 #endif
4249                     // switch mode
4250                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4251                     hci_emit_state();
4252                     break;
4253 
4254                 default:
4255                     break;
4256             }
4257             break;
4258 
4259         default:
4260             break;
4261     }
4262 }
4263 
4264 int hci_send_cmd_packet(uint8_t *packet, int size){
4265     // house-keeping
4266 
4267 #ifdef ENABLE_CLASSIC
4268     bd_addr_t addr;
4269     hci_connection_t * conn;
4270 #endif
4271 #ifdef ENABLE_LE_CENTRAL
4272     uint8_t initiator_filter_policy;
4273 #endif
4274 
4275     uint16_t opcode = little_endian_read_16(packet, 0);
4276     switch (opcode) {
4277         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4278             hci_stack->loopback_mode = packet[3];
4279             break;
4280 
4281 #ifdef ENABLE_CLASSIC
4282         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4283             reverse_bd_addr(&packet[3], addr);
4284             log_info("Create_connection to %s", bd_addr_to_str(addr));
4285 
4286             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4287             if (!conn) {
4288                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4289                 if (!conn) {
4290                     // notify client that alloc failed
4291                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4292                     return -1; // packet not sent to controller
4293                 }
4294                 conn->state = SEND_CREATE_CONNECTION;
4295                 conn->role  = HCI_ROLE_MASTER;
4296             }
4297             log_info("conn state %u", conn->state);
4298             switch (conn->state) {
4299                 // if connection active exists
4300                 case OPEN:
4301                     // and OPEN, emit connection complete command
4302                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4303                     return -1; // packet not sent to controller
4304                 case RECEIVED_DISCONNECTION_COMPLETE:
4305                     // create connection triggered in disconnect complete event, let's do it now
4306                     break;
4307                 case SEND_CREATE_CONNECTION:
4308                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4309                     break;
4310                 default:
4311                     // otherwise, just ignore as it is already in the open process
4312                     return -1; // packet not sent to controller
4313             }
4314             conn->state = SENT_CREATE_CONNECTION;
4315 
4316             // track outgoing connection
4317             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4318             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4319             break;
4320         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4321             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4322             break;
4323         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4324             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4325             break;
4326         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4327             if (hci_stack->link_key_db) {
4328                 reverse_bd_addr(&packet[3], addr);
4329                 hci_stack->link_key_db->delete_link_key(addr);
4330             }
4331             break;
4332         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4333         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4334             reverse_bd_addr(&packet[3], addr);
4335             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4336             if (conn) {
4337                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4338             }
4339             break;
4340         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4341         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4342         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4343         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4344             reverse_bd_addr(&packet[3], addr);
4345             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4346             if (conn) {
4347                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4348             }
4349             break;
4350 
4351 #ifdef ENABLE_SCO_OVER_HCI
4352         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4353             // setup_synchronous_connection? Voice setting at offset 22
4354             // TODO: compare to current setting if sco connection already active
4355             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4356             break;
4357         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4358             // accept_synchronus_connection? Voice setting at offset 18
4359             // TODO: compare to current setting if sco connection already active
4360             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4361             break;
4362 #endif
4363 #endif
4364 
4365 #ifdef ENABLE_BLE
4366         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4367             hci_stack->le_random_address_set = 1;
4368             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4369             break;
4370 #ifdef ENABLE_LE_PERIPHERAL
4371         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4372             hci_stack->le_advertisements_active = packet[3];
4373             break;
4374 #endif
4375 #ifdef ENABLE_LE_CENTRAL
4376         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4377             // white list used?
4378             initiator_filter_policy = packet[7];
4379             switch (initiator_filter_policy) {
4380                 case 0:
4381                     // whitelist not used
4382                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4383                     break;
4384                 case 1:
4385                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4386                     break;
4387                 default:
4388                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4389                     break;
4390             }
4391             // track outgoing connection
4392             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
4393             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4394             break;
4395         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4396             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
4397             break;
4398 #endif
4399 #endif
4400         default:
4401             break;
4402     }
4403 
4404     hci_stack->num_cmd_packets--;
4405 
4406     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4407     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4408 }
4409 
4410 // disconnect because of security block
4411 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4412     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4413     if (!connection) return;
4414     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4415 }
4416 
4417 
4418 // Configure Secure Simple Pairing
4419 
4420 #ifdef ENABLE_CLASSIC
4421 
4422 // enable will enable SSP during init
4423 void gap_ssp_set_enable(int enable){
4424     hci_stack->ssp_enable = enable;
4425 }
4426 
4427 static int hci_local_ssp_activated(void){
4428     return gap_ssp_supported() && hci_stack->ssp_enable;
4429 }
4430 
4431 // if set, BTstack will respond to io capability request using authentication requirement
4432 void gap_ssp_set_io_capability(int io_capability){
4433     hci_stack->ssp_io_capability = io_capability;
4434 }
4435 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4436     hci_stack->ssp_authentication_requirement = authentication_requirement;
4437 }
4438 
4439 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4440 void gap_ssp_set_auto_accept(int auto_accept){
4441     hci_stack->ssp_auto_accept = auto_accept;
4442 }
4443 
4444 void gap_secure_connections_enable(bool enable){
4445     hci_stack->secure_connections_enable = enable;
4446 }
4447 
4448 #endif
4449 
4450 // va_list part of hci_send_cmd
4451 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4452     if (!hci_can_send_command_packet_now()){
4453         log_error("hci_send_cmd called but cannot send packet now");
4454         return 0;
4455     }
4456 
4457     // for HCI INITIALIZATION
4458     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4459     hci_stack->last_cmd_opcode = cmd->opcode;
4460 
4461     hci_reserve_packet_buffer();
4462     uint8_t * packet = hci_stack->hci_packet_buffer;
4463     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4464     int err = hci_send_cmd_packet(packet, size);
4465 
4466     // release packet buffer on error or for synchronous transport implementations
4467     if ((err < 0) || hci_transport_synchronous()){
4468         hci_release_packet_buffer();
4469         hci_emit_transport_packet_sent();
4470     }
4471 
4472     return err;
4473 }
4474 
4475 /**
4476  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4477  */
4478 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4479     va_list argptr;
4480     va_start(argptr, cmd);
4481     int res = hci_send_cmd_va_arg(cmd, argptr);
4482     va_end(argptr);
4483     return res;
4484 }
4485 
4486 // Create various non-HCI events.
4487 // TODO: generalize, use table similar to hci_create_command
4488 
4489 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4490     // dump packet
4491     if (dump) {
4492         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4493     }
4494 
4495     // dispatch to all event handlers
4496     btstack_linked_list_iterator_t it;
4497     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4498     while (btstack_linked_list_iterator_has_next(&it)){
4499         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4500         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4501     }
4502 }
4503 
4504 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4505     if (!hci_stack->acl_packet_handler) return;
4506     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4507 }
4508 
4509 #ifdef ENABLE_CLASSIC
4510 static void hci_notify_if_sco_can_send_now(void){
4511     // notify SCO sender if waiting
4512     if (!hci_stack->sco_waiting_for_can_send_now) return;
4513     if (hci_can_send_sco_packet_now()){
4514         hci_stack->sco_waiting_for_can_send_now = 0;
4515         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4516         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4517         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4518     }
4519 }
4520 
4521 // parsing end emitting has been merged to reduce code size
4522 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4523     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4524 
4525     uint8_t * eir_data;
4526     ad_context_t context;
4527     const uint8_t * name;
4528     uint8_t         name_len;
4529 
4530     if (size < 3) return;
4531 
4532     int event_type = hci_event_packet_get_type(packet);
4533     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4534     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4535 
4536     switch (event_type){
4537         case HCI_EVENT_INQUIRY_RESULT:
4538         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4539             if (size != (3 + (num_responses * 14))) return;
4540             break;
4541         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4542             if (size != 257) return;
4543             if (num_responses != 1) return;
4544             break;
4545         default:
4546             return;
4547     }
4548 
4549     // event[1] is set at the end
4550     int i;
4551     for (i=0; i<num_responses;i++){
4552         memset(event, 0, sizeof(event));
4553         event[0] = GAP_EVENT_INQUIRY_RESULT;
4554         uint8_t event_size = 18;    // if name is not set by EIR
4555 
4556         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4557         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4558         (void)memcpy(&event[9],
4559                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4560                      3); // class of device
4561         (void)memcpy(&event[12],
4562                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4563                      2); // clock offset
4564 
4565         switch (event_type){
4566             case HCI_EVENT_INQUIRY_RESULT:
4567                 // 14,15,16,17 = 0, size 18
4568                 break;
4569             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4570                 event[14] = 1;
4571                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4572                 // 16,17 = 0, size 18
4573                 break;
4574             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4575                 event[14] = 1;
4576                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4577                 // EIR packets only contain a single inquiry response
4578                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4579                 name = NULL;
4580                 // Iterate over EIR data
4581                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4582                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4583                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4584                     const uint8_t * data = ad_iterator_get_data(&context);
4585                     // Prefer Complete Local Name over Shortend Local Name
4586                     switch (data_type){
4587                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4588                             if (name) continue;
4589                             /* fall through */
4590                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4591                             name = data;
4592                             name_len = data_size;
4593                             break;
4594                         default:
4595                             break;
4596                     }
4597                 }
4598                 if (name){
4599                     event[16] = 1;
4600                     // truncate name if needed
4601                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4602                     event[17] = len;
4603                     (void)memcpy(&event[18], name, len);
4604                     event_size += len;
4605                 }
4606                 break;
4607         }
4608         event[1] = event_size - 2;
4609         hci_emit_event(event, event_size, 1);
4610     }
4611 }
4612 #endif
4613 
4614 void hci_emit_state(void){
4615     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4616     uint8_t event[3];
4617     event[0] = BTSTACK_EVENT_STATE;
4618     event[1] = sizeof(event) - 2u;
4619     event[2] = hci_stack->state;
4620     hci_emit_event(event, sizeof(event), 1);
4621 }
4622 
4623 #ifdef ENABLE_CLASSIC
4624 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4625     uint8_t event[13];
4626     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4627     event[1] = sizeof(event) - 2;
4628     event[2] = status;
4629     little_endian_store_16(event, 3, con_handle);
4630     reverse_bd_addr(address, &event[5]);
4631     event[11] = 1; // ACL connection
4632     event[12] = 0; // encryption disabled
4633     hci_emit_event(event, sizeof(event), 1);
4634 }
4635 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4636     if (disable_l2cap_timeouts) return;
4637     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4638     uint8_t event[4];
4639     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4640     event[1] = sizeof(event) - 2;
4641     little_endian_store_16(event, 2, conn->con_handle);
4642     hci_emit_event(event, sizeof(event), 1);
4643 }
4644 #endif
4645 
4646 #ifdef ENABLE_BLE
4647 #ifdef ENABLE_LE_CENTRAL
4648 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4649     uint8_t event[21];
4650     event[0] = HCI_EVENT_LE_META;
4651     event[1] = sizeof(event) - 2u;
4652     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4653     event[3] = status;
4654     little_endian_store_16(event, 4, con_handle);
4655     event[6] = 0; // TODO: role
4656     event[7] = address_type;
4657     reverse_bd_addr(address, &event[8]);
4658     little_endian_store_16(event, 14, 0); // interval
4659     little_endian_store_16(event, 16, 0); // latency
4660     little_endian_store_16(event, 18, 0); // supervision timeout
4661     event[20] = 0; // master clock accuracy
4662     hci_emit_event(event, sizeof(event), 1);
4663 }
4664 #endif
4665 #endif
4666 
4667 static void hci_emit_transport_packet_sent(void){
4668     // notify upper stack that it might be possible to send again
4669     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4670     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4671 }
4672 
4673 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4674     uint8_t event[6];
4675     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4676     event[1] = sizeof(event) - 2u;
4677     event[2] = 0; // status = OK
4678     little_endian_store_16(event, 3, con_handle);
4679     event[5] = reason;
4680     hci_emit_event(event, sizeof(event), 1);
4681 }
4682 
4683 static void hci_emit_nr_connections_changed(void){
4684     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4685     uint8_t event[3];
4686     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4687     event[1] = sizeof(event) - 2u;
4688     event[2] = nr_hci_connections();
4689     hci_emit_event(event, sizeof(event), 1);
4690 }
4691 
4692 static void hci_emit_hci_open_failed(void){
4693     log_info("BTSTACK_EVENT_POWERON_FAILED");
4694     uint8_t event[2];
4695     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4696     event[1] = sizeof(event) - 2u;
4697     hci_emit_event(event, sizeof(event), 1);
4698 }
4699 
4700 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4701     log_info("hci_emit_dedicated_bonding_result %u ", status);
4702     uint8_t event[9];
4703     int pos = 0;
4704     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4705     event[pos++] = sizeof(event) - 2u;
4706     event[pos++] = status;
4707     reverse_bd_addr(address, &event[pos]);
4708     hci_emit_event(event, sizeof(event), 1);
4709 }
4710 
4711 
4712 #ifdef ENABLE_CLASSIC
4713 
4714 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4715     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4716     uint8_t event[5];
4717     int pos = 0;
4718     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4719     event[pos++] = sizeof(event) - 2;
4720     little_endian_store_16(event, 2, con_handle);
4721     pos += 2;
4722     event[pos++] = level;
4723     hci_emit_event(event, sizeof(event), 1);
4724 }
4725 
4726 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4727     if (!connection) return LEVEL_0;
4728     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4729     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4730     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4731     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4732     // LEVEL 4 always requires 128 bit encrytion key size
4733     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4734         security_level = LEVEL_3;
4735     }
4736     return security_level;
4737 }
4738 
4739 static void hci_emit_discoverable_enabled(uint8_t enabled){
4740     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4741     uint8_t event[3];
4742     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4743     event[1] = sizeof(event) - 2;
4744     event[2] = enabled;
4745     hci_emit_event(event, sizeof(event), 1);
4746 }
4747 
4748 // query if remote side supports eSCO
4749 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4750     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4751     if (!connection) return 0;
4752     return (connection->remote_supported_features[0] & 1) != 0;
4753 }
4754 
4755 static bool hci_ssp_supported(hci_connection_t * connection){
4756     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4757     return (connection->bonding_flags & mask) == mask;
4758 }
4759 
4760 // query if remote side supports SSP
4761 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4762     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4763     if (!connection) return 0;
4764     return hci_ssp_supported(connection) ? 1 : 0;
4765 }
4766 
4767 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4768     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4769 }
4770 
4771 // GAP API
4772 /**
4773  * @bbrief enable/disable bonding. default is enabled
4774  * @praram enabled
4775  */
4776 void gap_set_bondable_mode(int enable){
4777     hci_stack->bondable = enable ? 1 : 0;
4778 }
4779 /**
4780  * @brief Get bondable mode.
4781  * @return 1 if bondable
4782  */
4783 int gap_get_bondable_mode(void){
4784     return hci_stack->bondable;
4785 }
4786 
4787 /**
4788  * @brief map link keys to security levels
4789  */
4790 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4791     switch (link_key_type){
4792         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4793             return LEVEL_4;
4794         case COMBINATION_KEY:
4795         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4796             return LEVEL_3;
4797         default:
4798             return LEVEL_2;
4799     }
4800 }
4801 
4802 /**
4803  * @brief map link keys to secure connection yes/no
4804  */
4805 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4806     switch (link_key_type){
4807         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4808         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4809             return 1;
4810         default:
4811             return 0;
4812     }
4813 }
4814 
4815 /**
4816  * @brief map link keys to authenticated
4817  */
4818 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4819     switch (link_key_type){
4820         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4821         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4822             return 1;
4823         default:
4824             return 0;
4825     }
4826 }
4827 
4828 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4829     log_info("gap_mitm_protection_required_for_security_level %u", level);
4830     return level > LEVEL_2;
4831 }
4832 
4833 /**
4834  * @brief get current security level
4835  */
4836 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4837     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4838     if (!connection) return LEVEL_0;
4839     return gap_security_level_for_connection(connection);
4840 }
4841 
4842 /**
4843  * @brief request connection to device to
4844  * @result GAP_AUTHENTICATION_RESULT
4845  */
4846 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4847     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4848     if (!connection){
4849         hci_emit_security_level(con_handle, LEVEL_0);
4850         return;
4851     }
4852     gap_security_level_t current_level = gap_security_level(con_handle);
4853     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4854         requested_level, connection->requested_security_level, current_level);
4855 
4856     // assumption: earlier requested security higher than current level => security request is active
4857     if (current_level < connection->requested_security_level){
4858         if (connection->requested_security_level < requested_level){
4859             // increase requested level as new level is higher
4860 
4861             // TODO: handle re-authentication when done
4862 
4863             connection->requested_security_level = requested_level;
4864         }
4865         return;
4866     }
4867 
4868     // no request active, notify if security sufficient
4869     if (requested_level <= current_level){
4870         hci_emit_security_level(con_handle, current_level);
4871         return;
4872     }
4873 
4874     // start pairing to increase security level
4875     connection->requested_security_level = requested_level;
4876 
4877 #if 0
4878     // sending encryption request without a link key results in an error.
4879     // TODO: figure out how to use it properly
4880 
4881     // would enabling ecnryption suffice (>= LEVEL_2)?
4882     if (hci_stack->link_key_db){
4883         link_key_type_t link_key_type;
4884         link_key_t      link_key;
4885         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4886             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4887                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4888                 return;
4889             }
4890         }
4891     }
4892 #endif
4893 
4894     // start to authenticate connection if not already active
4895     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
4896     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4897     hci_run();
4898 }
4899 
4900 /**
4901  * @brief start dedicated bonding with device. disconnect after bonding
4902  * @param device
4903  * @param request MITM protection
4904  * @result GAP_DEDICATED_BONDING_COMPLETE
4905  */
4906 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4907 
4908     // create connection state machine
4909     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4910 
4911     if (!connection){
4912         return BTSTACK_MEMORY_ALLOC_FAILED;
4913     }
4914 
4915     // delete linkn key
4916     gap_drop_link_key_for_bd_addr(device);
4917 
4918     // configure LEVEL_2/3, dedicated bonding
4919     connection->state = SEND_CREATE_CONNECTION;
4920     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4921     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4922     connection->bonding_flags = BONDING_DEDICATED;
4923 
4924     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4925 
4926     // handle: connnection failure (connection complete != ok)
4927     // handle: authentication failure
4928     // handle: disconnect on done
4929 
4930     hci_run();
4931 
4932     return 0;
4933 }
4934 #endif
4935 
4936 void gap_set_local_name(const char * local_name){
4937     hci_stack->local_name = local_name;
4938 }
4939 
4940 
4941 #ifdef ENABLE_BLE
4942 
4943 #ifdef ENABLE_LE_CENTRAL
4944 void gap_start_scan(void){
4945     hci_stack->le_scanning_enabled = true;
4946     hci_run();
4947 }
4948 
4949 void gap_stop_scan(void){
4950     hci_stack->le_scanning_enabled = false;
4951     hci_run();
4952 }
4953 
4954 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
4955     hci_stack->le_scan_type          = scan_type;
4956     hci_stack->le_scan_filter_policy = scanning_filter_policy;
4957     hci_stack->le_scan_interval      = scan_interval;
4958     hci_stack->le_scan_window        = scan_window;
4959     hci_stack->le_scanning_param_update = true;
4960     hci_run();
4961 }
4962 
4963 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4964     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
4965 }
4966 
4967 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4968     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4969     if (!conn){
4970         // disallow if le connection is already outgoing
4971         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
4972             log_error("le connection already active");
4973             return ERROR_CODE_COMMAND_DISALLOWED;
4974         }
4975 
4976         log_info("gap_connect: no connection exists yet, creating context");
4977         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4978         if (!conn){
4979             // notify client that alloc failed
4980             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4981             log_info("gap_connect: failed to alloc hci_connection_t");
4982             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4983         }
4984 
4985         // set le connecting state
4986         if (hci_is_le_connection_type(addr_type)){
4987             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
4988         }
4989 
4990         conn->state = SEND_CREATE_CONNECTION;
4991         log_info("gap_connect: send create connection next");
4992         hci_run();
4993         return ERROR_CODE_SUCCESS;
4994     }
4995 
4996     if (!hci_is_le_connection(conn) ||
4997         (conn->state == SEND_CREATE_CONNECTION) ||
4998         (conn->state == SENT_CREATE_CONNECTION)) {
4999         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5000         log_error("gap_connect: classic connection or connect is already being created");
5001         return GATT_CLIENT_IN_WRONG_STATE;
5002     }
5003 
5004     // check if connection was just disconnected
5005     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5006         log_info("gap_connect: send create connection (again)");
5007         conn->state = SEND_CREATE_CONNECTION;
5008         hci_run();
5009         return ERROR_CODE_SUCCESS;
5010     }
5011 
5012     log_info("gap_connect: context exists with state %u", conn->state);
5013     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5014     hci_run();
5015     return ERROR_CODE_SUCCESS;
5016 }
5017 
5018 // @assumption: only a single outgoing LE Connection exists
5019 static hci_connection_t * gap_get_outgoing_connection(void){
5020     btstack_linked_item_t *it;
5021     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5022         hci_connection_t * conn = (hci_connection_t *) it;
5023         if (!hci_is_le_connection(conn)) continue;
5024         switch (conn->state){
5025             case SEND_CREATE_CONNECTION:
5026             case SENT_CREATE_CONNECTION:
5027             case SENT_CANCEL_CONNECTION:
5028                 return conn;
5029             default:
5030                 break;
5031         };
5032     }
5033     return NULL;
5034 }
5035 
5036 uint8_t gap_connect_cancel(void){
5037     hci_connection_t * conn = gap_get_outgoing_connection();
5038     if (!conn) return 0;
5039     switch (conn->state){
5040         case SEND_CREATE_CONNECTION:
5041             // skip sending create connection and emit event instead
5042             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5043             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5044             btstack_memory_hci_connection_free( conn );
5045             break;
5046         case SENT_CREATE_CONNECTION:
5047             // request to send cancel connection
5048             conn->state = SEND_CANCEL_CONNECTION;
5049             hci_run();
5050             break;
5051         default:
5052             break;
5053     }
5054     return 0;
5055 }
5056 #endif
5057 
5058 #ifdef ENABLE_LE_CENTRAL
5059 /**
5060  * @brief Set connection parameters for outgoing connections
5061  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5062  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5063  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5064  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5065  * @param conn_latency, default: 4
5066  * @param supervision_timeout (unit: 10ms), default: 720 ms
5067  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5068  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5069  */
5070 
5071 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5072     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5073     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5074     hci_stack->le_connection_scan_interval = conn_scan_interval;
5075     hci_stack->le_connection_scan_window = conn_scan_window;
5076     hci_stack->le_connection_interval_min = conn_interval_min;
5077     hci_stack->le_connection_interval_max = conn_interval_max;
5078     hci_stack->le_connection_latency = conn_latency;
5079     hci_stack->le_supervision_timeout = supervision_timeout;
5080     hci_stack->le_minimum_ce_length = min_ce_length;
5081     hci_stack->le_maximum_ce_length = max_ce_length;
5082 }
5083 #endif
5084 
5085 /**
5086  * @brief Updates the connection parameters for a given LE connection
5087  * @param handle
5088  * @param conn_interval_min (unit: 1.25ms)
5089  * @param conn_interval_max (unit: 1.25ms)
5090  * @param conn_latency
5091  * @param supervision_timeout (unit: 10ms)
5092  * @returns 0 if ok
5093  */
5094 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5095     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5096     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5097     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5098     connection->le_conn_interval_min = conn_interval_min;
5099     connection->le_conn_interval_max = conn_interval_max;
5100     connection->le_conn_latency = conn_latency;
5101     connection->le_supervision_timeout = supervision_timeout;
5102     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5103     hci_run();
5104     return 0;
5105 }
5106 
5107 /**
5108  * @brief Request an update of the connection parameter for a given LE connection
5109  * @param handle
5110  * @param conn_interval_min (unit: 1.25ms)
5111  * @param conn_interval_max (unit: 1.25ms)
5112  * @param conn_latency
5113  * @param supervision_timeout (unit: 10ms)
5114  * @returns 0 if ok
5115  */
5116 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5117     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5118     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5119     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5120     connection->le_conn_interval_min = conn_interval_min;
5121     connection->le_conn_interval_max = conn_interval_max;
5122     connection->le_conn_latency = conn_latency;
5123     connection->le_supervision_timeout = supervision_timeout;
5124     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5125     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5126     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5127     return 0;
5128 }
5129 
5130 #ifdef ENABLE_LE_PERIPHERAL
5131 
5132 /**
5133  * @brief Set Advertisement Data
5134  * @param advertising_data_length
5135  * @param advertising_data (max 31 octets)
5136  * @note data is not copied, pointer has to stay valid
5137  */
5138 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5139     hci_stack->le_advertisements_data_len = advertising_data_length;
5140     hci_stack->le_advertisements_data = advertising_data;
5141     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5142     hci_run();
5143 }
5144 
5145 /**
5146  * @brief Set Scan Response Data
5147  * @param advertising_data_length
5148  * @param advertising_data (max 31 octets)
5149  * @note data is not copied, pointer has to stay valid
5150  */
5151 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5152     hci_stack->le_scan_response_data_len = scan_response_data_length;
5153     hci_stack->le_scan_response_data = scan_response_data;
5154     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5155     hci_run();
5156 }
5157 
5158 /**
5159  * @brief Set Advertisement Parameters
5160  * @param adv_int_min
5161  * @param adv_int_max
5162  * @param adv_type
5163  * @param direct_address_type
5164  * @param direct_address
5165  * @param channel_map
5166  * @param filter_policy
5167  *
5168  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5169  */
5170  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5171     uint8_t direct_address_typ, bd_addr_t direct_address,
5172     uint8_t channel_map, uint8_t filter_policy) {
5173 
5174     hci_stack->le_advertisements_interval_min = adv_int_min;
5175     hci_stack->le_advertisements_interval_max = adv_int_max;
5176     hci_stack->le_advertisements_type = adv_type;
5177     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5178     hci_stack->le_advertisements_channel_map = channel_map;
5179     hci_stack->le_advertisements_filter_policy = filter_policy;
5180     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5181                  6);
5182 
5183     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5184     hci_run();
5185  }
5186 
5187 /**
5188  * @brief Enable/Disable Advertisements
5189  * @param enabled
5190  */
5191 void gap_advertisements_enable(int enabled){
5192     hci_stack->le_advertisements_enabled = enabled;
5193     hci_update_advertisements_enabled_for_current_roles();
5194     hci_run();
5195 }
5196 
5197 #endif
5198 
5199 void hci_le_set_own_address_type(uint8_t own_address_type){
5200     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5201     if (own_address_type == hci_stack->le_own_addr_type) return;
5202     hci_stack->le_own_addr_type = own_address_type;
5203 
5204 #ifdef ENABLE_LE_PERIPHERAL
5205     // update advertisement parameters, too
5206     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5207     hci_run();
5208 #endif
5209 #ifdef ENABLE_LE_CENTRAL
5210     // note: we don't update scan parameters or modify ongoing connection attempts
5211 #endif
5212 }
5213 
5214 #endif
5215 
5216 uint8_t gap_disconnect(hci_con_handle_t handle){
5217     hci_connection_t * conn = hci_connection_for_handle(handle);
5218     if (!conn){
5219         hci_emit_disconnection_complete(handle, 0);
5220         return 0;
5221     }
5222     // ignore if already disconnected
5223     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5224         return 0;
5225     }
5226     conn->state = SEND_DISCONNECT;
5227     hci_run();
5228     return 0;
5229 }
5230 
5231 int gap_read_rssi(hci_con_handle_t con_handle){
5232     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5233     if (hci_connection == NULL) return 0;
5234     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5235     hci_run();
5236     return 1;
5237 }
5238 
5239 /**
5240  * @brief Get connection type
5241  * @param con_handle
5242  * @result connection_type
5243  */
5244 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5245     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5246     if (!conn) return GAP_CONNECTION_INVALID;
5247     switch (conn->address_type){
5248         case BD_ADDR_TYPE_LE_PUBLIC:
5249         case BD_ADDR_TYPE_LE_RANDOM:
5250             return GAP_CONNECTION_LE;
5251         case BD_ADDR_TYPE_SCO:
5252             return GAP_CONNECTION_SCO;
5253         case BD_ADDR_TYPE_ACL:
5254             return GAP_CONNECTION_ACL;
5255         default:
5256             return GAP_CONNECTION_INVALID;
5257     }
5258 }
5259 
5260 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5261     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5262     if (!conn) return HCI_ROLE_INVALID;
5263     return (hci_role_t) conn->role;
5264 }
5265 
5266 
5267 #ifdef ENABLE_CLASSIC
5268 uint8_t gap_request_role(bd_addr_t addr, hci_role_t role){
5269     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5270     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5271     conn->request_role = role;
5272     hci_run();
5273     return ERROR_CODE_SUCCESS;
5274 }
5275 #endif
5276 
5277 #ifdef ENABLE_BLE
5278 
5279 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){
5280     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5281     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5282 
5283     conn->le_phy_update_all_phys    = all_phys;
5284     conn->le_phy_update_tx_phys     = tx_phys;
5285     conn->le_phy_update_rx_phys     = rx_phys;
5286     conn->le_phy_update_phy_options = phy_options;
5287 
5288     hci_run();
5289 
5290     return 0;
5291 }
5292 
5293 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, bd_addr_t address){
5294     // check if already in list
5295     btstack_linked_list_iterator_t it;
5296     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5297     while (btstack_linked_list_iterator_has_next(&it)) {
5298         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5299         if (entry->address_type != address_type) {
5300             continue;
5301         }
5302         if (memcmp(entry->address, address, 6) != 0) {
5303             continue;
5304         }
5305         // already in there
5306         return ERROR_CODE_COMMAND_DISALLOWED;
5307     }
5308     // alloc and add to list
5309     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5310     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5311     entry->address_type = address_type;
5312     (void)memcpy(entry->address, address, 6);
5313     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5314     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5315     return ERROR_CODE_SUCCESS;
5316 }
5317 
5318 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address){
5319     btstack_linked_list_iterator_t it;
5320     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5321     while (btstack_linked_list_iterator_has_next(&it)){
5322         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5323         if (entry->address_type != address_type) {
5324             continue;
5325         }
5326         if (memcmp(entry->address, address, 6) != 0) {
5327             continue;
5328         }
5329         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5330             // remove from controller if already present
5331             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5332         }  else {
5333             // directly remove entry from whitelist
5334             btstack_linked_list_iterator_remove(&it);
5335             btstack_memory_whitelist_entry_free(entry);
5336         }
5337         return ERROR_CODE_SUCCESS;
5338     }
5339     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5340 }
5341 
5342 static void hci_whitelist_clear(void){
5343     btstack_linked_list_iterator_t it;
5344     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5345     while (btstack_linked_list_iterator_has_next(&it)){
5346         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5347         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5348             // remove from controller if already present
5349             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5350             continue;
5351         }
5352         // directly remove entry from whitelist
5353         btstack_linked_list_iterator_remove(&it);
5354         btstack_memory_whitelist_entry_free(entry);
5355     }
5356 }
5357 
5358 /**
5359  * @brief Clear Whitelist
5360  * @returns 0 if ok
5361  */
5362 uint8_t gap_whitelist_clear(void){
5363     hci_whitelist_clear();
5364     hci_run();
5365     return ERROR_CODE_SUCCESS;
5366 }
5367 
5368 /**
5369  * @brief Add Device to Whitelist
5370  * @param address_typ
5371  * @param address
5372  * @returns 0 if ok
5373  */
5374 uint8_t gap_whitelist_add(bd_addr_type_t address_type, bd_addr_t address){
5375     uint8_t status = hci_whitelist_add(address_type, address);
5376     if (status){
5377         return status;
5378     }
5379     hci_run();
5380     return ERROR_CODE_SUCCESS;
5381 }
5382 
5383 /**
5384  * @brief Remove Device from Whitelist
5385  * @param address_typ
5386  * @param address
5387  * @returns 0 if ok
5388  */
5389 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address){
5390     uint8_t status = hci_whitelist_remove(address_type, address);
5391     if (status){
5392         return status;
5393     }
5394     hci_run();
5395     return ERROR_CODE_SUCCESS;
5396 }
5397 
5398 #ifdef ENABLE_LE_CENTRAL
5399 /**
5400  *  @brief Connect with Whitelist
5401  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5402  *  @returns - if ok
5403  */
5404 uint8_t gap_connect_with_whitelist(void){
5405     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5406         return ERROR_CODE_COMMAND_DISALLOWED;
5407     }
5408     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5409     hci_run();
5410     return ERROR_CODE_SUCCESS;
5411 }
5412 
5413 /**
5414  * @brief Auto Connection Establishment - Start Connecting to device
5415  * @param address_typ
5416  * @param address
5417  * @returns 0 if ok
5418  */
5419 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5420     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5421         return ERROR_CODE_COMMAND_DISALLOWED;
5422     }
5423 
5424     uint8_t status = hci_whitelist_add(address_type, address);
5425     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
5426         return status;
5427     }
5428 
5429     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5430 
5431     hci_run();
5432     return ERROR_CODE_SUCCESS;
5433 }
5434 
5435 /**
5436  * @brief Auto Connection Establishment - Stop Connecting to device
5437  * @param address_typ
5438  * @param address
5439  * @returns 0 if ok
5440  */
5441 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5442     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5443         return ERROR_CODE_COMMAND_DISALLOWED;
5444     }
5445 
5446     hci_whitelist_remove(address_type, address);
5447     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5448         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5449     }
5450     hci_run();
5451     return 0;
5452 }
5453 
5454 /**
5455  * @brief Auto Connection Establishment - Stop everything
5456  * @note  Convenience function to stop all active auto connection attempts
5457  */
5458 uint8_t gap_auto_connection_stop_all(void){
5459     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5460         return ERROR_CODE_COMMAND_DISALLOWED;
5461     }
5462     hci_whitelist_clear();
5463     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5464     hci_run();
5465     return ERROR_CODE_SUCCESS;
5466 }
5467 
5468 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5469     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5470     if (!conn) return 0;
5471     return conn->le_connection_interval;
5472 }
5473 #endif
5474 #endif
5475 
5476 #ifdef ENABLE_CLASSIC
5477 /**
5478  * @brief Set Extended Inquiry Response data
5479  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5480  * @note has to be done before stack starts up
5481  */
5482 void gap_set_extended_inquiry_response(const uint8_t * data){
5483     hci_stack->eir_data = data;
5484 }
5485 
5486 /**
5487  * @brief Start GAP Classic Inquiry
5488  * @param duration in 1.28s units
5489  * @return 0 if ok
5490  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5491  */
5492 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5493     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5494     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5495     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5496         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5497     }
5498     hci_stack->inquiry_state = duration_in_1280ms_units;
5499     hci_run();
5500     return 0;
5501 }
5502 
5503 /**
5504  * @brief Stop GAP Classic Inquiry
5505  * @returns 0 if ok
5506  */
5507 int gap_inquiry_stop(void){
5508     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5509         // emit inquiry complete event, before it even started
5510         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5511         hci_emit_event(event, sizeof(event), 1);
5512         return 0;
5513     }
5514     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5515     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5516     hci_run();
5517     return 0;
5518 }
5519 
5520 
5521 /**
5522  * @brief Remote Name Request
5523  * @param addr
5524  * @param page_scan_repetition_mode
5525  * @param clock_offset only used when bit 15 is set
5526  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5527  */
5528 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5529     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5530     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5531     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5532     hci_stack->remote_name_clock_offset = clock_offset;
5533     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5534     hci_run();
5535     return 0;
5536 }
5537 
5538 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5539     hci_stack->gap_pairing_state = state;
5540     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5541     hci_run();
5542     return 0;
5543 }
5544 
5545 /**
5546  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5547  * @param addr
5548  * @param pin_data
5549  * @param pin_len
5550  * @return 0 if ok
5551  */
5552 int gap_pin_code_response_binary(bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5553     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5554     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5555     hci_stack->gap_pairing_pin_len = pin_len;
5556     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5557 }
5558 
5559 /**
5560  * @brief Legacy Pairing Pin Code Response
5561  * @param addr
5562  * @param pin
5563  * @return 0 if ok
5564  */
5565 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5566     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5567 }
5568 
5569 /**
5570  * @brief Abort Legacy Pairing
5571  * @param addr
5572  * @param pin
5573  * @return 0 if ok
5574  */
5575 int gap_pin_code_negative(bd_addr_t addr){
5576     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5577     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5578 }
5579 
5580 /**
5581  * @brief SSP Passkey Response
5582  * @param addr
5583  * @param passkey
5584  * @return 0 if ok
5585  */
5586 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5587     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5588     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5589     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5590 }
5591 
5592 /**
5593  * @brief Abort SSP Passkey Entry/Pairing
5594  * @param addr
5595  * @param pin
5596  * @return 0 if ok
5597  */
5598 int gap_ssp_passkey_negative(bd_addr_t addr){
5599     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5600     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5601 }
5602 
5603 /**
5604  * @brief Accept SSP Numeric Comparison
5605  * @param addr
5606  * @param passkey
5607  * @return 0 if ok
5608  */
5609 int gap_ssp_confirmation_response(bd_addr_t addr){
5610     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5611     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5612 }
5613 
5614 /**
5615  * @brief Abort SSP Numeric Comparison/Pairing
5616  * @param addr
5617  * @param pin
5618  * @return 0 if ok
5619  */
5620 int gap_ssp_confirmation_negative(bd_addr_t addr){
5621     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5622     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5623 }
5624 
5625 /**
5626  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5627  * @param inquiry_mode see bluetooth_defines.h
5628  */
5629 void hci_set_inquiry_mode(inquiry_mode_t mode){
5630     hci_stack->inquiry_mode = mode;
5631 }
5632 
5633 /**
5634  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5635  */
5636 void hci_set_sco_voice_setting(uint16_t voice_setting){
5637     hci_stack->sco_voice_setting = voice_setting;
5638 }
5639 
5640 /**
5641  * @brief Get SCO Voice Setting
5642  * @return current voice setting
5643  */
5644 uint16_t hci_get_sco_voice_setting(void){
5645     return hci_stack->sco_voice_setting;
5646 }
5647 
5648 static int hci_have_usb_transport(void){
5649     if (!hci_stack->hci_transport) return 0;
5650     const char * transport_name = hci_stack->hci_transport->name;
5651     if (!transport_name) return 0;
5652     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5653 }
5654 
5655 /** @brief Get SCO packet length for current SCO Voice setting
5656  *  @note  Using SCO packets of the exact length is required for USB transfer
5657  *  @return Length of SCO packets in bytes (not audio frames)
5658  */
5659 int hci_get_sco_packet_length(void){
5660     int sco_packet_length = 0;
5661 
5662 #ifdef ENABLE_SCO_OVER_HCI
5663 
5664     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5665     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5666 
5667     if (hci_have_usb_transport()){
5668         // see Core Spec for H2 USB Transfer.
5669         // 3 byte SCO header + 24 bytes per connection
5670         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5671         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5672     } else {
5673         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5674         sco_packet_length = 3 + 60 * multiplier;
5675         // assert that it still fits inside an SCO buffer
5676         if (sco_packet_length > hci_stack->sco_data_packet_length){
5677             sco_packet_length = 3 + 60;
5678         }
5679     }
5680 #endif
5681     return sco_packet_length;
5682 }
5683 
5684 /**
5685 * @brief Sets the master/slave policy
5686 * @param policy (0: attempt to become master, 1: let connecting device decide)
5687 */
5688 void hci_set_master_slave_policy(uint8_t policy){
5689     hci_stack->master_slave_policy = policy;
5690 }
5691 
5692 #endif
5693 
5694 HCI_STATE hci_get_state(void){
5695     return hci_stack->state;
5696 }
5697 
5698 #ifdef ENABLE_CLASSIC
5699 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5700     hci_stack->gap_classic_accept_callback = accept_callback;
5701 }
5702 #endif
5703 
5704 /**
5705  * @brief Set callback for Bluetooth Hardware Error
5706  */
5707 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5708     hci_stack->hardware_error_callback = fn;
5709 }
5710 
5711 void hci_disconnect_all(void){
5712     btstack_linked_list_iterator_t it;
5713     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5714     while (btstack_linked_list_iterator_has_next(&it)){
5715         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5716         if (con->state == SENT_DISCONNECT) continue;
5717         con->state = SEND_DISCONNECT;
5718     }
5719     hci_run();
5720 }
5721 
5722 uint16_t hci_get_manufacturer(void){
5723     return hci_stack->manufacturer;
5724 }
5725 
5726 #ifdef ENABLE_BLE
5727 
5728 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5729     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5730     if (!hci_con) return NULL;
5731     return &hci_con->sm_connection;
5732 }
5733 
5734 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5735 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5736 
5737 int gap_encryption_key_size(hci_con_handle_t con_handle){
5738     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5739     if (hci_connection == NULL) return 0;
5740     if (hci_is_le_connection(hci_connection)){
5741         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5742         if (sm_conn->sm_connection_encrypted) {
5743             return sm_conn->sm_actual_encryption_key_size;
5744         }
5745     }
5746 #ifdef ENABLE_CLASSIC
5747     else {
5748         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5749             return hci_connection->encryption_key_size;
5750         }
5751     }
5752 #endif
5753     return 0;
5754 }
5755 
5756 int gap_authenticated(hci_con_handle_t con_handle){
5757     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5758     if (hci_connection == NULL) return 0;
5759 
5760     switch (hci_connection->address_type){
5761         case BD_ADDR_TYPE_LE_PUBLIC:
5762         case BD_ADDR_TYPE_LE_RANDOM:
5763             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5764             return hci_connection->sm_connection.sm_connection_authenticated;
5765 #ifdef ENABLE_CLASSIC
5766         case BD_ADDR_TYPE_SCO:
5767         case BD_ADDR_TYPE_ACL:
5768             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5769 #endif
5770         default:
5771             return 0;
5772     }
5773 }
5774 
5775 int gap_secure_connection(hci_con_handle_t con_handle){
5776     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5777     if (hci_connection == NULL) return 0;
5778 
5779     switch (hci_connection->address_type){
5780         case BD_ADDR_TYPE_LE_PUBLIC:
5781         case BD_ADDR_TYPE_LE_RANDOM:
5782             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5783             return hci_connection->sm_connection.sm_connection_sc;
5784 #ifdef ENABLE_CLASSIC
5785         case BD_ADDR_TYPE_SCO:
5786         case BD_ADDR_TYPE_ACL:
5787             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5788 #endif
5789         default:
5790             return 0;
5791     }
5792 }
5793 
5794 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5795     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5796     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5797     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5798     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5799     return sm_conn->sm_connection_authorization_state;
5800 }
5801 #endif
5802 
5803 #ifdef ENABLE_CLASSIC
5804 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){
5805     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5806     if (!conn) return GAP_CONNECTION_INVALID;
5807     conn->sniff_min_interval = sniff_min_interval;
5808     conn->sniff_max_interval = sniff_max_interval;
5809     conn->sniff_attempt = sniff_attempt;
5810     conn->sniff_timeout = sniff_timeout;
5811     hci_run();
5812     return 0;
5813 }
5814 
5815 /**
5816  * @brief Exit Sniff mode
5817  * @param con_handle
5818  @ @return 0 if ok
5819  */
5820 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5821     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5822     if (!conn) return GAP_CONNECTION_INVALID;
5823     conn->sniff_min_interval = 0xffff;
5824     hci_run();
5825     return 0;
5826 }
5827 #endif
5828 
5829 void hci_halting_defer(void){
5830     if (hci_stack->state != HCI_STATE_HALTING) return;
5831     switch (hci_stack->substate){
5832         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5833         case HCI_HALTING_CLOSE:
5834             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5835             break;
5836         default:
5837             break;
5838     }
5839 }
5840 
5841 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5842 void hci_setup_test_connections_fuzz(void){
5843     hci_connection_t * conn;
5844 
5845     // default address: 66:55:44:33:00:01
5846     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5847 
5848     // setup Controller info
5849     hci_stack->num_cmd_packets = 255;
5850     hci_stack->acl_packets_total_num = 255;
5851 
5852     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5853     addr[5] = 0x01;
5854     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5855     conn->con_handle = addr[5];
5856     conn->role  = HCI_ROLE_SLAVE;
5857     conn->state = RECEIVED_CONNECTION_REQUEST;
5858     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5859 
5860     // setup incoming Classic SCO connection with con handle 0x0002
5861     addr[5] = 0x02;
5862     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5863     conn->con_handle = addr[5];
5864     conn->role  = HCI_ROLE_SLAVE;
5865     conn->state = RECEIVED_CONNECTION_REQUEST;
5866     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5867 
5868     // setup ready Classic ACL connection with con handle 0x0003
5869     addr[5] = 0x03;
5870     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5871     conn->con_handle = addr[5];
5872     conn->role  = HCI_ROLE_SLAVE;
5873     conn->state = OPEN;
5874     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5875 
5876     // setup ready Classic SCO connection with con handle 0x0004
5877     addr[5] = 0x04;
5878     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5879     conn->con_handle = addr[5];
5880     conn->role  = HCI_ROLE_SLAVE;
5881     conn->state = OPEN;
5882     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5883 
5884     // setup ready LE ACL connection with con handle 0x005 and public address
5885     addr[5] = 0x05;
5886     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5887     conn->con_handle = addr[5];
5888     conn->role  = HCI_ROLE_SLAVE;
5889     conn->state = OPEN;
5890     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5891 }
5892 
5893 void hci_free_connections_fuzz(void){
5894     btstack_linked_list_iterator_t it;
5895     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5896     while (btstack_linked_list_iterator_has_next(&it)){
5897         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5898         btstack_linked_list_iterator_remove(&it);
5899         btstack_memory_hci_connection_free(con);
5900     }
5901 }
5902 void hci_simulate_working_fuzz(void){
5903     hci_init_done();
5904     hci_stack->num_cmd_packets = 255;
5905 }
5906 #endif
5907