xref: /btstack/src/hci.c (revision 9dc32eb425c45f51cd4be899bc05cae06f314fba)
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 <stdio.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static 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 void hci_remove_from_whitelist(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->address_type = addr_type;
198     conn->con_handle = 0xffff;
199     conn->authentication_flags = AUTH_FLAGS_NONE;
200     conn->bonding_flags = 0;
201     conn->requested_security_level = LEVEL_0;
202 #ifdef ENABLE_CLASSIC
203     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
204     btstack_run_loop_set_timer_context(&conn->timeout, conn);
205     hci_connection_timestamp(conn);
206 #endif
207     conn->acl_recombination_length = 0;
208     conn->acl_recombination_pos = 0;
209     conn->num_packets_sent = 0;
210 
211     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
212 #ifdef ENABLE_BLE
213     conn->le_phy_update_all_phys = 0xff;
214 #endif
215 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
216     conn->le_max_tx_octets = 27;
217 #endif
218     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
219     return conn;
220 }
221 
222 
223 /**
224  * get le connection parameter range
225 *
226  * @return le connection parameter range struct
227  */
228 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
229     *range = hci_stack->le_connection_parameter_range;
230 }
231 
232 /**
233  * set le connection parameter range
234  *
235  */
236 
237 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
238     hci_stack->le_connection_parameter_range = *range;
239 }
240 
241 /**
242  * @brief Test if connection parameters are inside in existing rage
243  * @param conn_interval_min (unit: 1.25ms)
244  * @param conn_interval_max (unit: 1.25ms)
245  * @param conn_latency
246  * @param supervision_timeout (unit: 10ms)
247  * @returns 1 if included
248  */
249 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){
250     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
251     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
252 
253     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
254     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
255 
256     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
257     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
258 
259     return 1;
260 }
261 
262 /**
263  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
264  * @note: default: 1
265  * @param max_peripheral_connections
266  */
267 #ifdef ENABLE_LE_PERIPHERAL
268 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
269     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
270 }
271 #endif
272 
273 /**
274  * get hci connections iterator
275  *
276  * @return hci connections iterator
277  */
278 
279 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
280     btstack_linked_list_iterator_init(it, &hci_stack->connections);
281 }
282 
283 /**
284  * get connection for a given handle
285  *
286  * @return connection OR NULL, if not found
287  */
288 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
289     btstack_linked_list_iterator_t it;
290     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
291     while (btstack_linked_list_iterator_has_next(&it)){
292         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
293         if ( item->con_handle == con_handle ) {
294             return item;
295         }
296     }
297     return NULL;
298 }
299 
300 /**
301  * get connection for given address
302  *
303  * @return connection OR NULL, if not found
304  */
305 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
306     btstack_linked_list_iterator_t it;
307     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
308     while (btstack_linked_list_iterator_has_next(&it)){
309         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
310         if (connection->address_type != addr_type)  continue;
311         if (memcmp(addr, connection->address, 6) != 0) continue;
312         return connection;
313     }
314     return NULL;
315 }
316 
317 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
318     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
319 }
320 
321 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
322     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
323 }
324 
325 #ifdef ENABLE_CLASSIC
326 
327 #ifdef ENABLE_SCO_OVER_HCI
328 static int hci_number_sco_connections(void){
329     int connections = 0;
330     btstack_linked_list_iterator_t it;
331     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
332     while (btstack_linked_list_iterator_has_next(&it)){
333         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
334         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
335         connections++;
336     }
337     return connections;
338 }
339 #endif
340 
341 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
342     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
343 #ifdef HAVE_EMBEDDED_TICK
344     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
345         // connections might be timed out
346         hci_emit_l2cap_check_timeout(connection);
347     }
348 #else
349     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
350         // connections might be timed out
351         hci_emit_l2cap_check_timeout(connection);
352     }
353 #endif
354 }
355 
356 static void hci_connection_timestamp(hci_connection_t *connection){
357 #ifdef HAVE_EMBEDDED_TICK
358     connection->timestamp = btstack_run_loop_embedded_get_ticks();
359 #else
360     connection->timestamp = btstack_run_loop_get_time_ms();
361 #endif
362 }
363 
364 /**
365  * add authentication flags and reset timer
366  * @note: assumes classic connection
367  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
368  */
369 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
370     bd_addr_t addr;
371     reverse_bd_addr(bd_addr, addr);
372     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
373     if (conn) {
374         connectionSetAuthenticationFlags(conn, flags);
375         hci_connection_timestamp(conn);
376     }
377 }
378 
379 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
380     hci_connection_t * conn = hci_connection_for_handle(handle);
381     if (!conn) return 0;
382     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
383     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
384     return 0;
385 }
386 
387 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
388     if (!hci_stack->link_key_db) return;
389     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
390     hci_stack->link_key_db->delete_link_key(addr);
391 }
392 
393 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
394     if (!hci_stack->link_key_db) return;
395     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
396     hci_stack->link_key_db->put_link_key(addr, link_key, type);
397 }
398 
399 void gap_delete_all_link_keys(void){
400     bd_addr_t  addr;
401     link_key_t link_key;
402     link_key_type_t type;
403     btstack_link_key_iterator_t it;
404     int ok = gap_link_key_iterator_init(&it);
405     if (!ok) {
406         log_error("could not initialize iterator");
407         return;
408     }
409     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
410         gap_drop_link_key_for_bd_addr(addr);
411     }
412     gap_link_key_iterator_done(&it);
413 }
414 
415 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
416     if (!hci_stack->link_key_db) return 0;
417     if (!hci_stack->link_key_db->iterator_init) return 0;
418     return hci_stack->link_key_db->iterator_init(it);
419 }
420 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){
421     if (!hci_stack->link_key_db) return 0;
422     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
423 }
424 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
425     if (!hci_stack->link_key_db) return;
426     hci_stack->link_key_db->iterator_done(it);
427 }
428 #endif
429 
430 static int hci_is_le_connection(hci_connection_t * connection){
431     switch (connection->address_type){
432         case BD_ADDR_TYPE_LE_PUBLIC:
433         case BD_ADDR_TYPE_LE_RANDOM:
434         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
435         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
436             return 1;
437         default:
438             return 0;
439     }
440 }
441 
442 /**
443  * count connections
444  */
445 static int nr_hci_connections(void){
446     int count = 0;
447     btstack_linked_item_t *it;
448     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
449         count++;
450     }
451     return count;
452 }
453 
454 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
455 
456     unsigned int num_packets_sent_classic = 0;
457     unsigned int num_packets_sent_le = 0;
458 
459     btstack_linked_item_t *it;
460     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
461         hci_connection_t * connection = (hci_connection_t *) it;
462         if (hci_is_le_connection(connection)){
463             num_packets_sent_le += connection->num_packets_sent;
464         }
465         if (connection->address_type == BD_ADDR_TYPE_ACL){
466             num_packets_sent_classic += connection->num_packets_sent;
467         }
468     }
469     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
470     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
471     int free_slots_le = 0;
472 
473     if (free_slots_classic < 0){
474         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);
475         return 0;
476     }
477 
478     if (hci_stack->le_acl_packets_total_num){
479         // if we have LE slots, they are used
480         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
481         if (free_slots_le < 0){
482             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);
483             return 0;
484         }
485     } else {
486         // otherwise, classic slots are used for LE, too
487         free_slots_classic -= num_packets_sent_le;
488         if (free_slots_classic < 0){
489             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);
490             return 0;
491         }
492     }
493 
494     switch (address_type){
495         case BD_ADDR_TYPE_UNKNOWN:
496             log_error("hci_number_free_acl_slots: unknown address type");
497             return 0;
498 
499         case BD_ADDR_TYPE_ACL:
500             return free_slots_classic;
501 
502         default:
503            if (hci_stack->le_acl_packets_total_num){
504                return free_slots_le;
505            }
506            return free_slots_classic;
507     }
508 }
509 
510 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
511     // get connection type
512     hci_connection_t * connection = hci_connection_for_handle(con_handle);
513     if (!connection){
514         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
515         return 0;
516     }
517     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
518 }
519 
520 #ifdef ENABLE_CLASSIC
521 static int hci_number_free_sco_slots(void){
522     unsigned int num_sco_packets_sent  = 0;
523     btstack_linked_item_t *it;
524     if (hci_stack->synchronous_flow_control_enabled){
525         // explicit flow control
526         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
527             hci_connection_t * connection = (hci_connection_t *) it;
528             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
529             num_sco_packets_sent += connection->num_packets_sent;
530         }
531         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
532             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
533             return 0;
534         }
535         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
536     } else {
537         // implicit flow control -- TODO
538         int num_ready = 0;
539         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
540             hci_connection_t * connection = (hci_connection_t *) it;
541             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
542             if (connection->sco_tx_ready == 0) continue;
543             num_ready++;
544         }
545         return num_ready;
546     }
547 }
548 #endif
549 
550 // only used to send HCI Host Number Completed Packets
551 static int hci_can_send_comand_packet_transport(void){
552     if (hci_stack->hci_packet_buffer_reserved) return 0;
553 
554     // check for async hci transport implementations
555     if (hci_stack->hci_transport->can_send_packet_now){
556         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
557             return 0;
558         }
559     }
560     return 1;
561 }
562 
563 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
564 int hci_can_send_command_packet_now(void){
565     if (hci_can_send_comand_packet_transport() == 0) return 0;
566     return hci_stack->num_cmd_packets > 0;
567 }
568 
569 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
570     // check for async hci transport implementations
571     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
572     return hci_stack->hci_transport->can_send_packet_now(packet_type);
573 }
574 
575 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
576     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
577     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
578 }
579 
580 int hci_can_send_acl_le_packet_now(void){
581     if (hci_stack->hci_packet_buffer_reserved) return 0;
582     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
583 }
584 
585 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
586     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
587     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
588 }
589 
590 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
591     if (hci_stack->hci_packet_buffer_reserved) return 0;
592     return hci_can_send_prepared_acl_packet_now(con_handle);
593 }
594 
595 #ifdef ENABLE_CLASSIC
596 int hci_can_send_acl_classic_packet_now(void){
597     if (hci_stack->hci_packet_buffer_reserved) return 0;
598     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
599 }
600 
601 int hci_can_send_prepared_sco_packet_now(void){
602     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
603     if (hci_have_usb_transport()){
604         return hci_stack->sco_can_send_now;
605     } else {
606         return hci_number_free_sco_slots() > 0;
607     }
608 }
609 
610 int hci_can_send_sco_packet_now(void){
611     if (hci_stack->hci_packet_buffer_reserved) return 0;
612     return hci_can_send_prepared_sco_packet_now();
613 }
614 
615 void hci_request_sco_can_send_now_event(void){
616     hci_stack->sco_waiting_for_can_send_now = 1;
617     hci_notify_if_sco_can_send_now();
618 }
619 #endif
620 
621 // used for internal checks in l2cap.c
622 int hci_is_packet_buffer_reserved(void){
623     return hci_stack->hci_packet_buffer_reserved;
624 }
625 
626 // reserves outgoing packet buffer. @returns 1 if successful
627 int hci_reserve_packet_buffer(void){
628     if (hci_stack->hci_packet_buffer_reserved) {
629         log_error("hci_reserve_packet_buffer called but buffer already reserved");
630         return 0;
631     }
632     hci_stack->hci_packet_buffer_reserved = 1;
633     return 1;
634 }
635 
636 void hci_release_packet_buffer(void){
637     hci_stack->hci_packet_buffer_reserved = 0;
638 }
639 
640 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
641 static int hci_transport_synchronous(void){
642     return hci_stack->hci_transport->can_send_packet_now == NULL;
643 }
644 
645 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
646 
647     // 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);
648 
649     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
650     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
651     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0)){
652         max_acl_data_packet_length = hci_stack->le_data_packets_length;
653     }
654 
655 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
656     if (hci_is_le_connection(connection)){
657         max_acl_data_packet_length = connection->le_max_tx_octets;
658     }
659 #endif
660 
661     log_debug("hci_send_acl_packet_fragments entered");
662 
663     int err;
664     // multiple packets could be send on a synchronous HCI transport
665     while (true){
666 
667         log_debug("hci_send_acl_packet_fragments loop entered");
668 
669         // get current data
670         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
671         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
672         int more_fragments = 0;
673 
674         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
675         if (current_acl_data_packet_length > max_acl_data_packet_length){
676             more_fragments = 1;
677             current_acl_data_packet_length = max_acl_data_packet_length;
678         }
679 
680         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
681         if (acl_header_pos > 0){
682             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
683             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
684             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
685         }
686 
687         // update header len
688         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
689 
690         // count packet
691         connection->num_packets_sent++;
692         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
693 
694         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
695         if (more_fragments){
696             // update start of next fragment to send
697             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
698         } else {
699             // done
700             hci_stack->acl_fragmentation_pos = 0;
701             hci_stack->acl_fragmentation_total_size = 0;
702         }
703 
704         // send packet
705         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
706         const int size = current_acl_data_packet_length + 4;
707         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
708         hci_stack->acl_fragmentation_tx_active = 1;
709         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
710 
711         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
712 
713         // done yet?
714         if (!more_fragments) break;
715 
716         // can send more?
717         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
718     }
719 
720     log_debug("hci_send_acl_packet_fragments loop over");
721 
722     // release buffer now for synchronous transport
723     if (hci_transport_synchronous()){
724         hci_stack->acl_fragmentation_tx_active = 0;
725         hci_release_packet_buffer();
726         hci_emit_transport_packet_sent();
727     }
728 
729     return err;
730 }
731 
732 // pre: caller has reserved the packet buffer
733 int hci_send_acl_packet_buffer(int size){
734 
735     // log_info("hci_send_acl_packet_buffer size %u", size);
736 
737     if (!hci_stack->hci_packet_buffer_reserved) {
738         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
739         return 0;
740     }
741 
742     uint8_t * packet = hci_stack->hci_packet_buffer;
743     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
744 
745     // check for free places on Bluetooth module
746     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
747         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
748         hci_release_packet_buffer();
749         hci_emit_transport_packet_sent();
750         return BTSTACK_ACL_BUFFERS_FULL;
751     }
752 
753     hci_connection_t *connection = hci_connection_for_handle( con_handle);
754     if (!connection) {
755         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
756         hci_release_packet_buffer();
757         hci_emit_transport_packet_sent();
758         return 0;
759     }
760 
761 #ifdef ENABLE_CLASSIC
762     hci_connection_timestamp(connection);
763 #endif
764 
765     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
766 
767     // setup data
768     hci_stack->acl_fragmentation_total_size = size;
769     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
770 
771     return hci_send_acl_packet_fragments(connection);
772 }
773 
774 #ifdef ENABLE_CLASSIC
775 // pre: caller has reserved the packet buffer
776 int hci_send_sco_packet_buffer(int size){
777 
778     // log_info("hci_send_acl_packet_buffer size %u", size);
779 
780     if (!hci_stack->hci_packet_buffer_reserved) {
781         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
782         return 0;
783     }
784 
785     uint8_t * packet = hci_stack->hci_packet_buffer;
786 
787     // skip checks in loopback mode
788     if (!hci_stack->loopback_mode){
789         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
790 
791         // check for free places on Bluetooth module
792         if (!hci_can_send_prepared_sco_packet_now()) {
793             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
794             hci_release_packet_buffer();
795             hci_emit_transport_packet_sent();
796             return BTSTACK_ACL_BUFFERS_FULL;
797         }
798 
799         // track send packet in connection struct
800         hci_connection_t *connection = hci_connection_for_handle( con_handle);
801         if (!connection) {
802             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
803             hci_release_packet_buffer();
804             hci_emit_transport_packet_sent();
805             return 0;
806         }
807 
808         if (hci_have_usb_transport()){
809             // token used
810             hci_stack->sco_can_send_now = 0;
811         } else {
812             if (hci_stack->synchronous_flow_control_enabled){
813                 connection->num_packets_sent++;
814             } else {
815                 connection->sco_tx_ready--;
816             }
817         }
818     }
819 
820     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
821     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
822 
823     if (hci_transport_synchronous()){
824         hci_release_packet_buffer();
825         hci_emit_transport_packet_sent();
826     }
827 
828     return err;
829 }
830 #endif
831 
832 static void acl_handler(uint8_t *packet, int size){
833 
834     // log_info("acl_handler: size %u", size);
835 
836     // get info
837     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
838     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
839     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
840     uint16_t acl_length         = READ_ACL_LENGTH(packet);
841 
842     // ignore non-registered handle
843     if (!conn){
844         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
845         return;
846     }
847 
848     // assert packet is complete
849     if ((acl_length + 4) != size){
850         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
851         return;
852     }
853 
854 #ifdef ENABLE_CLASSIC
855     // update idle timestamp
856     hci_connection_timestamp(conn);
857 #endif
858 
859 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
860     hci_stack->host_completed_packets = 1;
861     conn->num_packets_completed++;
862 #endif
863 
864     // handle different packet types
865     switch (acl_flags & 0x03) {
866 
867         case 0x01: // continuation fragment
868 
869             // sanity checks
870             if (conn->acl_recombination_pos == 0) {
871                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
872                 return;
873             }
874             if ((conn->acl_recombination_pos + acl_length) > (4 + HCI_ACL_BUFFER_SIZE)){
875                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
876                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
877                 conn->acl_recombination_pos = 0;
878                 return;
879             }
880 
881             // append fragment payload (header already stored)
882             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
883                          &packet[4], acl_length);
884             conn->acl_recombination_pos += acl_length;
885 
886             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
887             //        conn->acl_recombination_pos, conn->acl_recombination_length);
888 
889             // forward complete L2CAP packet if complete.
890             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4 + 4)){ // pos already incl. ACL header
891                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
892                 // reset recombination buffer
893                 conn->acl_recombination_length = 0;
894                 conn->acl_recombination_pos = 0;
895             }
896             break;
897 
898         case 0x02: { // first fragment
899 
900             // sanity check
901             if (conn->acl_recombination_pos) {
902                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
903                 conn->acl_recombination_pos = 0;
904             }
905 
906             // peek into L2CAP packet!
907             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
908 
909             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
910 
911             // compare fragment size to L2CAP packet size
912             if (acl_length >= (l2cap_length + 4)){
913                 // forward fragment as L2CAP packet
914                 hci_emit_acl_packet(packet, acl_length + 4);
915             } else {
916 
917                 if (acl_length > HCI_ACL_BUFFER_SIZE){
918                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
919                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
920                     return;
921                 }
922 
923                 // store first fragment and tweak acl length for complete package
924                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
925                              packet, acl_length + 4);
926                 conn->acl_recombination_pos    = acl_length + 4;
927                 conn->acl_recombination_length = l2cap_length;
928                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
929             }
930             break;
931 
932         }
933         default:
934             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
935             return;
936     }
937 
938     // execute main loop
939     hci_run();
940 }
941 
942 static void hci_shutdown_connection(hci_connection_t *conn){
943     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
944 
945 #ifdef ENABLE_CLASSIC
946 #ifdef ENABLE_SCO_OVER_HCI
947     int addr_type = conn->address_type;
948 #endif
949 #endif
950 
951     btstack_run_loop_remove_timer(&conn->timeout);
952 
953     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
954     btstack_memory_hci_connection_free( conn );
955 
956     // now it's gone
957     hci_emit_nr_connections_changed();
958 
959 #ifdef ENABLE_CLASSIC
960 #ifdef ENABLE_SCO_OVER_HCI
961     // update SCO
962     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
963         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
964     }
965 #endif
966 #endif
967 }
968 
969 #ifdef ENABLE_CLASSIC
970 
971 static const uint16_t packet_type_sizes[] = {
972     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
973     HCI_ACL_DH1_SIZE, 0, 0, 0,
974     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
975     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
976 };
977 static const uint8_t  packet_type_feature_requirement_bit[] = {
978      0, // 3 slot packets
979      1, // 5 slot packets
980     25, // EDR 2 mpbs
981     26, // EDR 3 mbps
982     39, // 3 slot EDR packts
983     40, // 5 slot EDR packet
984 };
985 static const uint16_t packet_type_feature_packet_mask[] = {
986     0x0f00, // 3 slot packets
987     0xf000, // 5 slot packets
988     0x1102, // EDR 2 mpbs
989     0x2204, // EDR 3 mbps
990     0x0300, // 3 slot EDR packts
991     0x3000, // 5 slot EDR packet
992 };
993 
994 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
995     // enable packet types based on size
996     uint16_t packet_types = 0;
997     unsigned int i;
998     for (i=0;i<16;i++){
999         if (packet_type_sizes[i] == 0) continue;
1000         if (packet_type_sizes[i] <= buffer_size){
1001             packet_types |= 1 << i;
1002         }
1003     }
1004     // disable packet types due to missing local supported features
1005     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1006         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1007         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1008         if (feature_set) continue;
1009         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1010         packet_types &= ~packet_type_feature_packet_mask[i];
1011     }
1012     // flip bits for "may not be used"
1013     packet_types ^= 0x3306;
1014     return packet_types;
1015 }
1016 
1017 uint16_t hci_usable_acl_packet_types(void){
1018     return hci_stack->packet_types;
1019 }
1020 #endif
1021 
1022 uint8_t* hci_get_outgoing_packet_buffer(void){
1023     // hci packet buffer is >= acl data packet length
1024     return hci_stack->hci_packet_buffer;
1025 }
1026 
1027 uint16_t hci_max_acl_data_packet_length(void){
1028     return hci_stack->acl_data_packet_length;
1029 }
1030 
1031 #ifdef ENABLE_CLASSIC
1032 int hci_extended_sco_link_supported(void){
1033     // No. 31, byte 3, bit 7
1034     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1035 }
1036 #endif
1037 
1038 int hci_non_flushable_packet_boundary_flag_supported(void){
1039     // No. 54, byte 6, bit 6
1040     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1041 }
1042 
1043 static int gap_ssp_supported(void){
1044     // No. 51, byte 6, bit 3
1045     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1046 }
1047 
1048 static int hci_classic_supported(void){
1049 #ifdef ENABLE_CLASSIC
1050     // No. 37, byte 4, bit 5, = No BR/EDR Support
1051     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1052 #else
1053     return 0;
1054 #endif
1055 }
1056 
1057 static int hci_le_supported(void){
1058 #ifdef ENABLE_BLE
1059     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1060     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1061 #else
1062     return 0;
1063 #endif
1064 }
1065 
1066 #ifdef ENABLE_BLE
1067 
1068 /**
1069  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1070  */
1071 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1072     *addr_type = hci_stack->le_own_addr_type;
1073     if (hci_stack->le_own_addr_type){
1074         (void)memcpy(addr, hci_stack->le_random_address, 6);
1075     } else {
1076         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1077     }
1078 }
1079 
1080 #ifdef ENABLE_LE_CENTRAL
1081 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1082 
1083     int offset = 3;
1084     int num_reports = packet[offset];
1085     offset += 1;
1086 
1087     int i;
1088     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1089     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1090     for (i=0; (i<num_reports) && (offset < size);i++){
1091         // sanity checks on data_length:
1092         uint8_t data_length = packet[offset + 8];
1093         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1094         if ((offset + 9 + data_length + 1) > size)    return;
1095         // setup event
1096         uint8_t event_size = 10 + data_length;
1097         int pos = 0;
1098         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1099         event[pos++] = event_size;
1100         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1101         offset += 8;
1102         pos += 8;
1103         event[pos++] = packet[offset + 1 + data_length]; // rssi
1104         event[pos++] = data_length;
1105         offset++;
1106         (void)memcpy(&event[pos], &packet[offset], data_length);
1107         pos +=    data_length;
1108         offset += data_length + 1; // rssi
1109         hci_emit_event(event, pos, 1);
1110     }
1111 }
1112 #endif
1113 #endif
1114 
1115 #ifdef ENABLE_BLE
1116 #ifdef ENABLE_LE_PERIPHERAL
1117 static void hci_reenable_advertisements_if_needed(void){
1118     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1119         // get number of active le slave connections
1120         int num_slave_connections = 0;
1121         btstack_linked_list_iterator_t it;
1122         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1123         while (btstack_linked_list_iterator_has_next(&it)){
1124             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1125             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1126             if (con->state != OPEN) continue;
1127             if (con->role  != HCI_ROLE_SLAVE) continue;
1128             if (!hci_is_le_connection(con)) continue;
1129             num_slave_connections++;
1130         }
1131         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1132         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1133             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1134         }
1135     }
1136 }
1137 #endif
1138 #endif
1139 
1140 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1141 
1142 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1143     if (!hci_stack->config) return 0;
1144     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1145     // Limit baud rate for Broadcom chipsets to 3 mbps
1146     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1147         baud_rate = 3000000;
1148     }
1149     return baud_rate;
1150 }
1151 
1152 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1153     UNUSED(ds);
1154 
1155     switch (hci_stack->substate){
1156         case HCI_INIT_W4_SEND_RESET:
1157             log_info("Resend HCI Reset");
1158             hci_stack->substate = HCI_INIT_SEND_RESET;
1159             hci_stack->num_cmd_packets = 1;
1160             hci_run();
1161             break;
1162         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1163             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1164             if (hci_stack->hci_transport->reset_link){
1165                 hci_stack->hci_transport->reset_link();
1166             }
1167 
1168             /* fall through */
1169 
1170         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1171             log_info("Resend HCI Reset - CSR Warm Boot");
1172             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1173             hci_stack->num_cmd_packets = 1;
1174             hci_run();
1175             break;
1176         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1177             if (hci_stack->hci_transport->set_baudrate){
1178                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1179                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1180                 hci_stack->hci_transport->set_baudrate(baud_rate);
1181             }
1182             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1183             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1184                 if (hci_stack->hci_transport->reset_link){
1185                     log_info("Link Reset");
1186                     hci_stack->hci_transport->reset_link();
1187                 }
1188                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1189                 hci_run();
1190             }
1191             break;
1192         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1193             // otherwise continue
1194             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1195             hci_send_cmd(&hci_read_local_supported_commands);
1196             break;
1197         default:
1198             break;
1199     }
1200 }
1201 #endif
1202 
1203 static void hci_initializing_next_state(void){
1204     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1205 }
1206 
1207 // assumption: hci_can_send_command_packet_now() == true
1208 static void hci_initializing_run(void){
1209     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1210     switch (hci_stack->substate){
1211         case HCI_INIT_SEND_RESET:
1212             hci_state_reset();
1213 
1214 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1215             // prepare reset if command complete not received in 100ms
1216             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1217             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1218             btstack_run_loop_add_timer(&hci_stack->timeout);
1219 #endif
1220             // send command
1221             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1222             hci_send_cmd(&hci_reset);
1223             break;
1224         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1225             hci_send_cmd(&hci_read_local_version_information);
1226             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1227             break;
1228         case HCI_INIT_SEND_READ_LOCAL_NAME:
1229             hci_send_cmd(&hci_read_local_name);
1230             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1231             break;
1232 
1233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1234         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1235             hci_state_reset();
1236             // prepare reset if command complete not received in 100ms
1237             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1238             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1239             btstack_run_loop_add_timer(&hci_stack->timeout);
1240             // send command
1241             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1242             hci_send_cmd(&hci_reset);
1243             break;
1244         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1245             hci_state_reset();
1246             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1247             hci_send_cmd(&hci_reset);
1248             break;
1249         case HCI_INIT_SEND_BAUD_CHANGE: {
1250             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1251             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1252             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1253             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1254             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1255             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1256             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1257             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1258                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1259                 btstack_run_loop_add_timer(&hci_stack->timeout);
1260             }
1261             break;
1262         }
1263         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1264             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1265             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1266             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1267             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1268             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1269             break;
1270         }
1271         case HCI_INIT_CUSTOM_INIT:
1272             // Custom initialization
1273             if (hci_stack->chipset && hci_stack->chipset->next_command){
1274                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1275                 int send_cmd = 0;
1276                 switch (hci_stack->chipset_result){
1277                     case BTSTACK_CHIPSET_VALID_COMMAND:
1278                         send_cmd = 1;
1279                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1280                         break;
1281                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1282                         send_cmd = 1;
1283                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1284                         log_info("CSR Warm Boot");
1285                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1286                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1287                         btstack_run_loop_add_timer(&hci_stack->timeout);
1288                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1289                             && hci_stack->config
1290                             && hci_stack->chipset
1291                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1292                             && hci_stack->hci_transport->set_baudrate
1293                             && hci_transport_uart_get_main_baud_rate()){
1294                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1295                         } else {
1296                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1297                         }
1298                         break;
1299                     default:
1300                         break;
1301                 }
1302 
1303                 if (send_cmd){
1304                     int size = 3 + hci_stack->hci_packet_buffer[2];
1305                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1306                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1307                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1308                     break;
1309                 }
1310                 log_info("Init script done");
1311 
1312                 // Init script download on Broadcom chipsets causes:
1313                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1314                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1315                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1316 
1317                     // - baud rate to reset, restore UART baud rate if needed
1318                     int need_baud_change = hci_stack->config
1319                         && hci_stack->chipset
1320                         && hci_stack->chipset->set_baudrate_command
1321                         && hci_stack->hci_transport->set_baudrate
1322                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1323                     if (need_baud_change) {
1324                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1325                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1326                         hci_stack->hci_transport->set_baudrate(baud_rate);
1327                     }
1328 
1329                     uint16_t bcm_delay_ms = 300;
1330                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1331                     //   -> Work around: wait here.
1332                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1333                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1334                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1335                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1336                     btstack_run_loop_add_timer(&hci_stack->timeout);
1337                     break;
1338                 }
1339             }
1340             // otherwise continue
1341             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1342             hci_send_cmd(&hci_read_local_supported_commands);
1343             break;
1344         case HCI_INIT_SET_BD_ADDR:
1345             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1346             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1347             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1348             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1349             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1350             break;
1351 #endif
1352 
1353         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1354             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1355             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1356             hci_send_cmd(&hci_read_local_supported_commands);
1357             break;
1358         case HCI_INIT_READ_BD_ADDR:
1359             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1360             hci_send_cmd(&hci_read_bd_addr);
1361             break;
1362         case HCI_INIT_READ_BUFFER_SIZE:
1363             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1364             hci_send_cmd(&hci_read_buffer_size);
1365             break;
1366         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1367             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1368             hci_send_cmd(&hci_read_local_supported_features);
1369             break;
1370 
1371 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1372         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1373             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1374             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1375             break;
1376         case HCI_INIT_HOST_BUFFER_SIZE:
1377             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1378             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1379                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1380             break;
1381 #endif
1382 
1383         case HCI_INIT_SET_EVENT_MASK:
1384             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1385             if (hci_le_supported()){
1386                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1387             } else {
1388                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1389                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1390             }
1391             break;
1392 
1393 #ifdef ENABLE_CLASSIC
1394         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1395             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1396             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1397             break;
1398         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1399             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1400             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1401             break;
1402         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1403             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1404             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1405             break;
1406         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1407             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1408             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1409             break;
1410         case HCI_INIT_WRITE_LOCAL_NAME: {
1411             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1412             hci_reserve_packet_buffer();
1413             uint8_t * packet = hci_stack->hci_packet_buffer;
1414             // construct HCI Command and send
1415             uint16_t opcode = hci_write_local_name.opcode;
1416             hci_stack->last_cmd_opcode = opcode;
1417             packet[0] = opcode & 0xff;
1418             packet[1] = opcode >> 8;
1419             packet[2] = DEVICE_NAME_LEN;
1420             memset(&packet[3], 0, DEVICE_NAME_LEN);
1421             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1422             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1423             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1424             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1425             // expand '00:00:00:00:00:00' in name with bd_addr
1426             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1427             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1428             break;
1429         }
1430         case HCI_INIT_WRITE_EIR_DATA: {
1431             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1432             hci_reserve_packet_buffer();
1433             uint8_t * packet = hci_stack->hci_packet_buffer;
1434             // construct HCI Command in-place and send
1435             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1436             hci_stack->last_cmd_opcode = opcode;
1437             uint16_t offset = 0;
1438             packet[offset++] = opcode & 0xff;
1439             packet[offset++] = opcode >> 8;
1440             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1441             packet[offset++] = 0;  // FEC not required
1442             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1443             if (hci_stack->eir_data){
1444                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1445                 ad_context_t context;
1446                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1447                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1448                     uint8_t size        = ad_iterator_get_data_len(&context);
1449                     const uint8_t *data = ad_iterator_get_data(&context);
1450                     // copy item
1451                     packet[offset++] = size + 1;
1452                     packet[offset++] = data_type;
1453                     memcpy(&packet[offset], data, size);
1454                     // update name item
1455                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1456                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1457                     }
1458                     offset += size;
1459                 }
1460             } else {
1461                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1462                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1463                 packet[offset++] = bytes_to_copy + 1;
1464                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1465                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1466                 // expand '00:00:00:00:00:00' in name with bd_addr
1467                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1468             }
1469             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1470             break;
1471         }
1472         case HCI_INIT_WRITE_INQUIRY_MODE:
1473             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1474             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1475             break;
1476         case HCI_INIT_WRITE_SCAN_ENABLE:
1477             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1478             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1479             break;
1480         // only sent if ENABLE_SCO_OVER_HCI is defined
1481         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1482             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1483             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1484             break;
1485         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1486             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1487             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1488             break;
1489         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1490         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1491             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1492             log_info("BCM: Route SCO data via HCI transport");
1493             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1494             break;
1495 
1496 #endif
1497 #ifdef ENABLE_BLE
1498         // LE INIT
1499         case HCI_INIT_LE_READ_BUFFER_SIZE:
1500             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1501             hci_send_cmd(&hci_le_read_buffer_size);
1502             break;
1503         case HCI_INIT_LE_SET_EVENT_MASK:
1504             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1505             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1506             break;
1507         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1508             // LE Supported Host = 1, Simultaneous Host = 0
1509             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1510             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1511             break;
1512 #endif
1513 
1514 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1515         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1516             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1517             hci_send_cmd(&hci_le_read_maximum_data_length);
1518             break;
1519         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1520             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1521             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1522             break;
1523 #endif
1524 
1525 #ifdef ENABLE_LE_CENTRAL
1526         case HCI_INIT_READ_WHITE_LIST_SIZE:
1527             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1528             hci_send_cmd(&hci_le_read_white_list_size);
1529             break;
1530         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1531             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1532             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1533             hci_send_cmd(&hci_le_set_scan_parameters, 1, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
1534             break;
1535 #endif
1536         default:
1537             return;
1538     }
1539 }
1540 
1541 static void hci_init_done(void){
1542     // done. tell the app
1543     log_info("hci_init_done -> HCI_STATE_WORKING");
1544     hci_stack->state = HCI_STATE_WORKING;
1545     hci_emit_state();
1546     hci_run();
1547 }
1548 
1549 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1550     bool command_completed = false;
1551     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1552         uint16_t opcode = little_endian_read_16(packet,3);
1553         if (opcode == hci_stack->last_cmd_opcode){
1554             command_completed = true;
1555             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1556         } else {
1557             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1558         }
1559     }
1560 
1561     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1562         uint8_t  status = packet[2];
1563         uint16_t opcode = little_endian_read_16(packet,4);
1564         if (opcode == hci_stack->last_cmd_opcode){
1565             if (status){
1566                 command_completed = true;
1567                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1568             } else {
1569                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1570             }
1571         } else {
1572             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1573         }
1574     }
1575 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1576     // Vendor == CSR
1577     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1578         // TODO: track actual command
1579         command_completed = true;
1580     }
1581 
1582     // Vendor == Toshiba
1583     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1584         // TODO: track actual command
1585         command_completed = true;
1586         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1587         hci_stack->num_cmd_packets = 1;
1588     }
1589 #endif
1590 
1591     return command_completed;
1592 }
1593 
1594 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1595 
1596     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1597 
1598     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1599 
1600 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1601 
1602     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1603     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1604     //
1605     // HCI Reset
1606     // Timeout 100 ms
1607     // HCI Reset
1608     // Command Complete Reset
1609     // HCI Read Local Version Information
1610     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1611     // hang...
1612     //
1613     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1614     if (!command_completed
1615             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1616             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1617 
1618         uint16_t opcode = little_endian_read_16(packet,3);
1619         if (opcode == hci_reset.opcode){
1620             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1621             return;
1622         }
1623     }
1624 
1625     // CSR & H5
1626     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1627     if (!command_completed
1628             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1629             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1630 
1631         uint16_t opcode = little_endian_read_16(packet,3);
1632         if (opcode == hci_reset.opcode){
1633             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1634             return;
1635         }
1636     }
1637 
1638     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1639     // fix: Correct substate and behave as command below
1640     if (command_completed){
1641         switch (hci_stack->substate){
1642             case HCI_INIT_SEND_RESET:
1643                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1644                 break;
1645             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1646                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1647                 break;
1648             default:
1649                 break;
1650         }
1651     }
1652 
1653 #endif
1654 
1655     if (!command_completed) return;
1656 
1657     bool need_baud_change = false;
1658     bool need_addr_change = false;
1659 
1660 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1661     need_baud_change = hci_stack->config
1662                         && hci_stack->chipset
1663                         && hci_stack->chipset->set_baudrate_command
1664                         && hci_stack->hci_transport->set_baudrate
1665                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1666 
1667     need_addr_change = hci_stack->custom_bd_addr_set
1668                         && hci_stack->chipset
1669                         && hci_stack->chipset->set_bd_addr_command;
1670 #endif
1671 
1672     switch(hci_stack->substate){
1673 
1674 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1675         case HCI_INIT_SEND_RESET:
1676             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1677             // fix: just correct substate and behave as command below
1678             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1679             btstack_run_loop_remove_timer(&hci_stack->timeout);
1680             break;
1681         case HCI_INIT_W4_SEND_RESET:
1682             btstack_run_loop_remove_timer(&hci_stack->timeout);
1683             break;
1684         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1685             log_info("Received local name, need baud change %d", (int) need_baud_change);
1686             if (need_baud_change){
1687                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1688                 return;
1689             }
1690             // skip baud change
1691             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1692             return;
1693         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1694             // for STLC2500D, baud rate change already happened.
1695             // for others, baud rate gets changed now
1696             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1697                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1698                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1699                 hci_stack->hci_transport->set_baudrate(baud_rate);
1700             }
1701             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1702             return;
1703         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1704             btstack_run_loop_remove_timer(&hci_stack->timeout);
1705             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1706             return;
1707         case HCI_INIT_W4_CUSTOM_INIT:
1708             // repeat custom init
1709             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1710             return;
1711 #else
1712         case HCI_INIT_W4_SEND_RESET:
1713             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1714             return ;
1715 #endif
1716 
1717         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1718             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1719               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1720                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1721                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1722                 return;
1723             }
1724             if (need_addr_change){
1725                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1726                 return;
1727             }
1728             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1729             return;
1730 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1731         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1732             if (need_baud_change){
1733                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1734                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1735                 hci_stack->hci_transport->set_baudrate(baud_rate);
1736             }
1737             if (need_addr_change){
1738                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1739                 return;
1740             }
1741             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1742             return;
1743         case HCI_INIT_W4_SET_BD_ADDR:
1744             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1745             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1746             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1747                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1748                 return;
1749             }
1750             // skipping st warm boot
1751             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1752             return;
1753         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1754             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1755             return;
1756 #endif
1757         case HCI_INIT_W4_READ_BD_ADDR:
1758             // only read buffer size if supported
1759             if (hci_stack->local_supported_commands[0] & 0x01) {
1760                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1761                 return;
1762             }
1763             // skipping read buffer size
1764             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1765             return;
1766         case HCI_INIT_W4_SET_EVENT_MASK:
1767             // skip Classic init commands for LE only chipsets
1768             if (!hci_classic_supported()){
1769 #ifdef ENABLE_BLE
1770                 if (hci_le_supported()){
1771                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1772                     return;
1773                 }
1774 #endif
1775                 log_error("Neither BR/EDR nor LE supported");
1776                 hci_init_done();
1777                 return;
1778             }
1779             if (!gap_ssp_supported()){
1780                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1781                 return;
1782             }
1783             break;
1784 #ifdef ENABLE_BLE
1785         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1786             // skip write le host if not supported (e.g. on LE only EM9301)
1787             if (hci_stack->local_supported_commands[0] & 0x02) break;
1788             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1789             return;
1790 
1791 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1792         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1793             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1794             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1795                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1796                 return;
1797             }
1798             // explicit fall through to reduce repetitions
1799 
1800 #ifdef ENABLE_LE_CENTRAL
1801             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1802 #else
1803             hci_init_done();
1804 #endif
1805             return;
1806 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1807 
1808 #endif  /* ENABLE_BLE */
1809 
1810 #ifdef ENABLE_SCO_OVER_HCI
1811         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1812             // skip write synchronous flow control if not supported
1813             if (hci_stack->local_supported_commands[0] & 0x04) break;
1814             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1815 
1816             /* fall through */
1817 
1818         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1819             // skip write default erroneous data reporting if not supported
1820             if (hci_stack->local_supported_commands[0] & 0x08) break;
1821             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1822 
1823             /* fall through */
1824 
1825         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1826             // skip bcm set sco pcm config on non-Broadcom chipsets
1827             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1828             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1829 
1830             /* fall through */
1831 
1832         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1833             if (!hci_le_supported()){
1834                 // SKIP LE init for Classic only configuration
1835                 hci_init_done();
1836                 return;
1837             }
1838             break;
1839 
1840 #else /* !ENABLE_SCO_OVER_HCI */
1841 
1842         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1843 #ifdef ENABLE_BLE
1844             if (hci_le_supported()){
1845                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1846                 return;
1847             }
1848 #endif
1849             // SKIP LE init for Classic only configuration
1850             hci_init_done();
1851             return;
1852 #endif /* ENABLE_SCO_OVER_HCI */
1853 
1854 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1855 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1856         // Response to command before init done state -> init done
1857         case (HCI_INIT_DONE-1):
1858             hci_init_done();
1859             return;
1860 #endif
1861 
1862         default:
1863             break;
1864     }
1865     hci_initializing_next_state();
1866 }
1867 
1868 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1869     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1870     bd_addr_t bd_address;
1871     (void)memcpy(&bd_address, conn->address, 6);
1872 
1873 #ifdef ENABLE_CLASSIC
1874     // cache needed data
1875     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1876 #endif
1877 
1878     // connection failed, remove entry
1879     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1880     btstack_memory_hci_connection_free( conn );
1881 
1882 #ifdef ENABLE_CLASSIC
1883     // notify client if dedicated bonding
1884     if (notify_dedicated_bonding_failed){
1885         log_info("hci notify_dedicated_bonding_failed");
1886         hci_emit_dedicated_bonding_result(bd_address, status);
1887     }
1888 
1889     // if authentication error, also delete link key
1890     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1891         gap_drop_link_key_for_bd_addr(bd_address);
1892     }
1893 #endif
1894 }
1895 
1896 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1897     // handle BT initialization
1898     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1899         hci_initializing_event_handler(packet, size);
1900     }
1901 
1902     // help with BT sleep
1903     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1904         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1905         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1906         hci_initializing_next_state();
1907     }
1908 }
1909 
1910 static void event_handler(uint8_t *packet, int size){
1911 
1912     uint16_t event_length = packet[1];
1913 
1914     // assert packet is complete
1915     if (size != (event_length + 2)){
1916         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1917         return;
1918     }
1919 
1920     bd_addr_t addr;
1921     bd_addr_type_t addr_type;
1922     hci_con_handle_t handle;
1923     hci_connection_t * conn;
1924     int i;
1925     int create_connection_cmd;
1926 
1927 #ifdef ENABLE_CLASSIC
1928     uint8_t link_type;
1929 #endif
1930 
1931     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1932 
1933     switch (hci_event_packet_get_type(packet)) {
1934 
1935         case HCI_EVENT_COMMAND_COMPLETE:
1936             // get num cmd packets - limit to 1 to reduce complexity
1937             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1938 
1939             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1940                 if (packet[5]) break;
1941                 // terminate, name 248 chars
1942                 packet[6+248] = 0;
1943                 log_info("local name: %s", &packet[6]);
1944             }
1945             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1946                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1947                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1948                     uint16_t acl_len = little_endian_read_16(packet, 6);
1949                     uint16_t sco_len = packet[8];
1950 
1951                     // determine usable ACL/SCO payload size
1952                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1953                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1954 
1955                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1956                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1957 
1958                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1959                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1960                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1961                 }
1962             }
1963             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
1964                 if (packet[5] == 0){
1965                     uint8_t event[5];
1966                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
1967                     event[1] = 3;
1968                     (void)memcpy(&event[2], &packet[6], 3);
1969                     hci_emit_event(event, sizeof(event), 1);
1970                 }
1971             }
1972 #ifdef ENABLE_BLE
1973             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1974                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1975                 hci_stack->le_acl_packets_total_num  = packet[8];
1976                 // determine usable ACL payload size
1977                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1978                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1979                 }
1980                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1981             }
1982 #endif
1983 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1984             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
1985                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
1986                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
1987                 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);
1988             }
1989 #endif
1990 #ifdef ENABLE_LE_CENTRAL
1991             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1992                 hci_stack->le_whitelist_capacity = packet[6];
1993                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1994             }
1995 #endif
1996             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1997                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1998 				hci_stack->local_bd_addr);
1999                 log_info("Local Address, Status: 0x%02x: Addr: %s",
2000                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2001 #ifdef ENABLE_CLASSIC
2002                 if (hci_stack->link_key_db){
2003                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2004                 }
2005 #endif
2006             }
2007 #ifdef ENABLE_CLASSIC
2008             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2009                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2010             }
2011             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2012                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2013                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2014                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2015                     hci_emit_event(event, sizeof(event), 1);
2016                 }
2017             }
2018 #endif
2019 
2020             // Note: HCI init checks
2021             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2022                 (void)memcpy(hci_stack->local_supported_features,
2023 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2024 			     8);
2025 
2026 #ifdef ENABLE_CLASSIC
2027                 // determine usable ACL packet types based on host buffer size and supported features
2028                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2029                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2030 #endif
2031                 // Classic/LE
2032                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2033             }
2034             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2035                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2036                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2037                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2038                 // map Cypress to Broadcom
2039                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2040                     log_info("Treat Cypress as Broadcom");
2041                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2042                     little_endian_store_16(packet, 10, manufacturer);
2043                 }
2044                 hci_stack->manufacturer = manufacturer;
2045                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2046                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2047                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2048             }
2049             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2050                 hci_stack->local_supported_commands[0] =
2051                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2052                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2053                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2054                      (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)       |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2055                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2056                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2057                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2058                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2059                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
2060             }
2061 #ifdef ENABLE_CLASSIC
2062             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2063                 if (packet[5] == 0){
2064                     hci_stack->synchronous_flow_control_enabled = 1;
2065                 }
2066             }
2067             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2068                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2069                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2070                 conn   = hci_connection_for_handle(handle);
2071                 if (!conn) break;
2072                 if (status == 0){
2073                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2074                     log_info("Handle %x04x key Size: %u", handle, key_size);
2075                     conn->encryption_key_size = key_size;
2076                 } else {
2077                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2078                     conn->encryption_key_size = 1;
2079                 }
2080                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2081                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2082             }
2083 #endif
2084             break;
2085 
2086         case HCI_EVENT_COMMAND_STATUS:
2087             // get num cmd packets - limit to 1 to reduce complexity
2088             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2089 
2090             // check command status to detected failed outgoing connections
2091             create_connection_cmd = 0;
2092 #ifdef ENABLE_CLASSIC
2093             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2094                 create_connection_cmd = 1;
2095             }
2096 #endif
2097 #ifdef ENABLE_LE_CENTRAL
2098             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2099                 create_connection_cmd = 1;
2100             }
2101 #endif
2102             if (create_connection_cmd) {
2103                 uint8_t status = hci_event_command_status_get_status(packet);
2104                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2105                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), hci_stack->outgoing_addr_type);
2106 
2107                 // reset outgoing address info
2108                 memset(hci_stack->outgoing_addr, 0, 6);
2109                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2110 
2111                 // error => outgoing connection failed
2112                 if ((conn != NULL) && (status != 0)){
2113                     hci_handle_connection_failed(conn, status);
2114                 }
2115             }
2116             break;
2117 
2118         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2119             if (size < 3) return;
2120             uint16_t num_handles = packet[2];
2121             if (size != (3 + num_handles * 4)) return;
2122             uint16_t offset = 3;
2123             for (i=0; i<num_handles;i++){
2124                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2125                 offset += 2;
2126                 uint16_t num_packets = little_endian_read_16(packet, offset);
2127                 offset += 2;
2128 
2129                 conn = hci_connection_for_handle(handle);
2130                 if (!conn){
2131                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2132                     continue;
2133                 }
2134 
2135                 if (conn->num_packets_sent >= num_packets){
2136                     conn->num_packets_sent -= num_packets;
2137                 } else {
2138                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2139                     conn->num_packets_sent = 0;
2140                 }
2141                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2142 
2143 #ifdef ENABLE_CLASSIC
2144                 // For SCO, we do the can_send_now_check here
2145                 hci_notify_if_sco_can_send_now();
2146 #endif
2147             }
2148             break;
2149         }
2150 
2151 #ifdef ENABLE_CLASSIC
2152         case HCI_EVENT_INQUIRY_COMPLETE:
2153             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2154                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2155                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2156                 hci_emit_event(event, sizeof(event), 1);
2157             }
2158             break;
2159         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2160             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2161                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2162             }
2163             break;
2164         case HCI_EVENT_CONNECTION_REQUEST:
2165             reverse_bd_addr(&packet[2], addr);
2166             if (hci_stack->gap_classic_accept_callback != NULL){
2167                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2168                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2169                     bd_addr_copy(hci_stack->decline_addr, addr);
2170                     break;
2171                 }
2172             }
2173 
2174             // TODO: eval COD 8-10
2175             link_type = packet[11];
2176             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2177             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2178             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2179             if (!conn) {
2180                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2181             }
2182             if (!conn) {
2183                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2184                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2185                 bd_addr_copy(hci_stack->decline_addr, addr);
2186                 break;
2187             }
2188             conn->role  = HCI_ROLE_SLAVE;
2189             conn->state = RECEIVED_CONNECTION_REQUEST;
2190             // store info about eSCO
2191             if (link_type == 0x02){
2192                 conn->remote_supported_feature_eSCO = 1;
2193             }
2194             hci_run();
2195             break;
2196 
2197         case HCI_EVENT_CONNECTION_COMPLETE:
2198             // Connection management
2199             reverse_bd_addr(&packet[5], addr);
2200             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2201             addr_type = BD_ADDR_TYPE_ACL;
2202             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2203             if (conn) {
2204                 if (!packet[2]){
2205                     conn->state = OPEN;
2206                     conn->con_handle = little_endian_read_16(packet, 3);
2207 
2208                     // queue get remote feature
2209                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
2210 
2211                     // queue set supervision timeout if we're master
2212                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2213                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2214                     }
2215 
2216                     // restart timer
2217                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2218                     btstack_run_loop_add_timer(&conn->timeout);
2219 
2220                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2221 
2222                     hci_emit_nr_connections_changed();
2223                 } else {
2224                     // connection failed
2225                     hci_handle_connection_failed(conn, packet[2]);
2226                 }
2227             }
2228             break;
2229 
2230         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2231             reverse_bd_addr(&packet[5], addr);
2232             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2233             if (packet[2]){
2234                 // connection failed
2235                 break;
2236             }
2237             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2238             if (!conn) {
2239                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2240             }
2241             if (!conn) {
2242                 break;
2243             }
2244             conn->state = OPEN;
2245             conn->con_handle = little_endian_read_16(packet, 3);
2246 
2247 #ifdef ENABLE_SCO_OVER_HCI
2248             // update SCO
2249             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2250                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2251             }
2252             // trigger can send now
2253             if (hci_have_usb_transport()){
2254                 hci_stack->sco_can_send_now = 1;
2255             }
2256 #endif
2257             break;
2258 
2259         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2260             handle = little_endian_read_16(packet, 3);
2261             conn = hci_connection_for_handle(handle);
2262             if (!conn) break;
2263             if (!packet[2]){
2264                 uint8_t * features = &packet[5];
2265                 if (features[6] & (1 << 3)){
2266                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
2267                 }
2268                 if (features[3] & (1<<7)){
2269                     conn->remote_supported_feature_eSCO = 1;
2270                 }
2271             }
2272             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2273             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
2274             if (conn->bonding_flags & BONDING_DEDICATED){
2275                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2276             }
2277             break;
2278 
2279         case HCI_EVENT_LINK_KEY_REQUEST:
2280             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2281             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2282             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2283             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2284             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2285             hci_run();
2286             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2287             return;
2288 
2289         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2290             reverse_bd_addr(&packet[2], addr);
2291             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2292             if (!conn) break;
2293             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2294             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2295             // Change Connection Encryption keeps link key type
2296             if (link_key_type != CHANGED_COMBINATION_KEY){
2297                 conn->link_key_type = link_key_type;
2298             }
2299             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2300             // still forward event to allow dismiss of pairing dialog
2301             break;
2302         }
2303 
2304         case HCI_EVENT_PIN_CODE_REQUEST:
2305             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2306             // non-bondable mode: pin code negative reply will be sent
2307             if (!hci_stack->bondable){
2308                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2309                 hci_run();
2310                 return;
2311             }
2312             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2313             if (!hci_stack->link_key_db) break;
2314             hci_event_pin_code_request_get_bd_addr(packet, addr);
2315             hci_stack->link_key_db->delete_link_key(addr);
2316             break;
2317 
2318         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2319             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2320             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2321             break;
2322 
2323         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2324             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2325             if (!hci_stack->ssp_auto_accept) break;
2326             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2327             break;
2328 
2329         case HCI_EVENT_USER_PASSKEY_REQUEST:
2330             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2331             if (!hci_stack->ssp_auto_accept) break;
2332             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2333             break;
2334         case HCI_EVENT_MODE_CHANGE:
2335             handle = hci_event_mode_change_get_handle(packet);
2336             conn = hci_connection_for_handle(handle);
2337             if (!conn) break;
2338             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2339             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2340             break;
2341 #endif
2342 
2343         case HCI_EVENT_ENCRYPTION_CHANGE:
2344             handle = little_endian_read_16(packet, 3);
2345             conn = hci_connection_for_handle(handle);
2346             if (!conn) break;
2347             if (packet[2] == 0) {
2348                 if (packet[5]){
2349                     if (hci_is_le_connection(conn)){
2350                         // For LE, we accept connection as encrypted
2351                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2352                     }
2353 #ifdef ENABLE_CLASSIC
2354                     else {
2355                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2356                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2357                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2358                         } else {
2359                             // if not, pretend everything is perfect
2360                             conn->encryption_key_size = 16;
2361                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2362                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2363                         }
2364                     }
2365 #endif
2366                 } else {
2367                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2368                 }
2369             }
2370 
2371             break;
2372 
2373 #ifdef ENABLE_CLASSIC
2374         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2375             handle = little_endian_read_16(packet, 3);
2376             conn = hci_connection_for_handle(handle);
2377             if (!conn) break;
2378 
2379             // dedicated bonding: send result and disconnect
2380             if (conn->bonding_flags & BONDING_DEDICATED){
2381                 conn->bonding_flags &= ~BONDING_DEDICATED;
2382                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2383                 conn->bonding_status = packet[2];
2384                 break;
2385             }
2386 
2387             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2388                 // link key sufficient for requested security
2389                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2390                 break;
2391             }
2392             // not enough
2393             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2394             break;
2395 #endif
2396 
2397         // HCI_EVENT_DISCONNECTION_COMPLETE
2398         // has been split, to first notify stack before shutting connection down
2399         // see end of function, too.
2400         case HCI_EVENT_DISCONNECTION_COMPLETE:
2401             if (packet[2]) break;   // status != 0
2402             handle = little_endian_read_16(packet, 3);
2403             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2404             if (hci_stack->acl_fragmentation_total_size > 0) {
2405                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2406                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2407                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2408                     hci_stack->acl_fragmentation_total_size = 0;
2409                     hci_stack->acl_fragmentation_pos = 0;
2410                     if (release_buffer){
2411                         hci_release_packet_buffer();
2412                     }
2413                 }
2414             }
2415 
2416             conn = hci_connection_for_handle(handle);
2417             if (!conn) break;
2418             // mark connection for shutdown
2419             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2420 
2421             // emit dedicatd bonding event
2422             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2423                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2424             }
2425 
2426 #ifdef ENABLE_BLE
2427 #ifdef ENABLE_LE_PERIPHERAL
2428             // re-enable advertisements for le connections if active
2429             if (hci_is_le_connection(conn)){
2430                 hci_reenable_advertisements_if_needed();
2431             }
2432 #endif
2433 #endif
2434             break;
2435 
2436         case HCI_EVENT_HARDWARE_ERROR:
2437             log_error("Hardware Error: 0x%02x", packet[2]);
2438             if (hci_stack->hardware_error_callback){
2439                 (*hci_stack->hardware_error_callback)(packet[2]);
2440             } else {
2441                 // if no special requests, just reboot stack
2442                 hci_power_control_off();
2443                 hci_power_control_on();
2444             }
2445             break;
2446 
2447 #ifdef ENABLE_CLASSIC
2448         case HCI_EVENT_ROLE_CHANGE:
2449             if (packet[2]) break;   // status != 0
2450             reverse_bd_addr(&packet[3], addr);
2451             addr_type = BD_ADDR_TYPE_ACL;
2452             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2453             if (!conn) break;
2454             conn->role = packet[9];
2455             break;
2456 #endif
2457 
2458         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2459             // release packet buffer only for asynchronous transport and if there are not further fragements
2460             if (hci_transport_synchronous()) {
2461                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2462                 return; // instead of break: to avoid re-entering hci_run()
2463             }
2464             hci_stack->acl_fragmentation_tx_active = 0;
2465             if (hci_stack->acl_fragmentation_total_size) break;
2466             hci_release_packet_buffer();
2467 
2468             // L2CAP receives this event via the hci_emit_event below
2469 
2470 #ifdef ENABLE_CLASSIC
2471             // For SCO, we do the can_send_now_check here
2472             hci_notify_if_sco_can_send_now();
2473 #endif
2474             break;
2475 
2476 #ifdef ENABLE_CLASSIC
2477         case HCI_EVENT_SCO_CAN_SEND_NOW:
2478             // For SCO, we do the can_send_now_check here
2479             hci_stack->sco_can_send_now = 1;
2480             hci_notify_if_sco_can_send_now();
2481             return;
2482 
2483         // explode inquriy results for easier consumption
2484         case HCI_EVENT_INQUIRY_RESULT:
2485         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2486         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2487             gap_inquiry_explode(packet, size);
2488             break;
2489 #endif
2490 
2491 #ifdef ENABLE_BLE
2492         case HCI_EVENT_LE_META:
2493             switch (packet[2]){
2494 #ifdef ENABLE_LE_CENTRAL
2495                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2496                     // log_info("advertising report received");
2497                     if (!hci_stack->le_scanning_enabled) break;
2498                     le_handle_advertisement_report(packet, size);
2499                     break;
2500 #endif
2501                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2502                     // Connection management
2503                     reverse_bd_addr(&packet[8], addr);
2504                     addr_type = (bd_addr_type_t)packet[7];
2505                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2506                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2507 
2508 #ifdef ENABLE_LE_CENTRAL
2509                     // if auto-connect, remove from whitelist in both roles
2510                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2511                         hci_remove_from_whitelist(addr_type, addr);
2512                     }
2513                     // handle error: error is reported only to the initiator -> outgoing connection
2514                     if (packet[3]){
2515 
2516                         // handle cancelled outgoing connection
2517                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2518                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2519                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2520                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2521                             conn = gap_get_outgoing_connection();
2522                         }
2523 
2524                         // outgoing connection establishment is done
2525                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2526                         // remove entry
2527                         if (conn){
2528                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2529                             btstack_memory_hci_connection_free( conn );
2530                         }
2531                         break;
2532                     }
2533 #endif
2534                     // on success, both hosts receive connection complete event
2535                     if (packet[6] == HCI_ROLE_MASTER){
2536 #ifdef ENABLE_LE_CENTRAL
2537                         // if we're master, it was an outgoing connection and we're done with it
2538                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2539 #endif
2540                     } else {
2541 #ifdef ENABLE_LE_PERIPHERAL
2542                         // if we're slave, it was an incoming connection, advertisements have stopped
2543                         hci_stack->le_advertisements_active = 0;
2544 #endif
2545                     }
2546                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2547                     if (!conn){
2548                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2549                     }
2550                     // no memory, sorry.
2551                     if (!conn){
2552                         break;
2553                     }
2554 
2555                     conn->state = OPEN;
2556                     conn->role  = packet[6];
2557                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2558                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2559 
2560 #ifdef ENABLE_LE_PERIPHERAL
2561                     if (packet[6] == HCI_ROLE_SLAVE){
2562                         hci_reenable_advertisements_if_needed();
2563                     }
2564 #endif
2565 
2566                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2567 
2568                     // restart timer
2569                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2570                     // btstack_run_loop_add_timer(&conn->timeout);
2571 
2572                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2573 
2574                     hci_emit_nr_connections_changed();
2575                     break;
2576 
2577                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2578                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2579                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2580                     conn = hci_connection_for_handle(handle);
2581                     if (!conn) break;
2582                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2583                     break;
2584 
2585                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2586                     // connection
2587                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2588                     conn = hci_connection_for_handle(handle);
2589                     if (conn) {
2590                         // read arguments
2591                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2592                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2593                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2594                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2595 
2596                         // validate against current connection parameter range
2597                         le_connection_parameter_range_t existing_range;
2598                         gap_get_connection_parameter_range(&existing_range);
2599                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2600                         if (update_parameter){
2601                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2602                             conn->le_conn_interval_min = le_conn_interval_min;
2603                             conn->le_conn_interval_max = le_conn_interval_max;
2604                             conn->le_conn_latency = le_conn_latency;
2605                             conn->le_supervision_timeout = le_supervision_timeout;
2606                         } else {
2607                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2608                         }
2609                     }
2610                     break;
2611 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2612                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2613                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2614                     conn = hci_connection_for_handle(handle);
2615                     if (conn) {
2616                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2617                     }
2618                     break;
2619 #endif
2620                 default:
2621                     break;
2622             }
2623             break;
2624 #endif
2625         case HCI_EVENT_VENDOR_SPECIFIC:
2626             // Vendor specific commands often create vendor specific event instead of num completed packets
2627             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2628             switch (hci_stack->manufacturer){
2629                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2630                     hci_stack->num_cmd_packets = 1;
2631                     break;
2632                 default:
2633                     break;
2634             }
2635             break;
2636         default:
2637             break;
2638     }
2639 
2640     handle_event_for_current_stack_state(packet, size);
2641 
2642     // notify upper stack
2643 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2644 
2645     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2646     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2647         if (!packet[2]){
2648             handle = little_endian_read_16(packet, 3);
2649             hci_connection_t * aConn = hci_connection_for_handle(handle);
2650             if (aConn) {
2651                 // discard connection if app did not trigger a reconnect in the event handler
2652                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2653                     hci_shutdown_connection(aConn);
2654                 }
2655             }
2656         }
2657     }
2658 
2659 	// execute main loop
2660 	hci_run();
2661 }
2662 
2663 #ifdef ENABLE_CLASSIC
2664 
2665 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2666 static void sco_schedule_tx(hci_connection_t * conn);
2667 
2668 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2669     log_debug("SCO TX Timeout");
2670     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2671     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2672     if (!conn) return;
2673 
2674     // trigger send
2675     conn->sco_tx_ready = 1;
2676     // extra packet if CVSD but SCO buffer is too short
2677     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2678         conn->sco_tx_ready++;
2679     }
2680     hci_notify_if_sco_can_send_now();
2681 }
2682 
2683 
2684 #define SCO_TX_AFTER_RX_MS (6)
2685 
2686 static void sco_schedule_tx(hci_connection_t * conn){
2687 
2688     uint32_t now = btstack_run_loop_get_time_ms();
2689     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2690     int time_delta_ms = sco_tx_ms - now;
2691 
2692     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2693 
2694     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2695     btstack_run_loop_set_timer(timer, time_delta_ms);
2696     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2697     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2698     btstack_run_loop_add_timer(timer);
2699 }
2700 
2701 static void sco_handler(uint8_t * packet, uint16_t size){
2702     // lookup connection struct
2703     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2704     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2705     if (!conn) return;
2706 
2707     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2708     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2709         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2710             packet[2] = 0x3c;
2711             memmove(&packet[3], &packet[23], 63);
2712             size = 63;
2713         }
2714     }
2715 
2716     if (hci_have_usb_transport()){
2717         // Nothing to do
2718     } else {
2719         // 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);
2720         if (hci_stack->synchronous_flow_control_enabled == 0){
2721             uint32_t now = btstack_run_loop_get_time_ms();
2722 
2723             if (!conn->sco_rx_valid){
2724                 // ignore first 10 packets
2725                 conn->sco_rx_count++;
2726                 // log_debug("sco rx count %u", conn->sco_rx_count);
2727                 if (conn->sco_rx_count == 10) {
2728                     // use first timestamp as is and pretent it just started
2729                     conn->sco_rx_ms = now;
2730                     conn->sco_rx_valid = 1;
2731                     conn->sco_rx_count = 0;
2732                     sco_schedule_tx(conn);
2733                 }
2734             } else {
2735                 // track expected arrival timme
2736                 conn->sco_rx_count++;
2737                 conn->sco_rx_ms += 7;
2738                 int delta = (int32_t) (now - conn->sco_rx_ms);
2739                 if (delta > 0){
2740                     conn->sco_rx_ms++;
2741                 }
2742                 // log_debug("sco rx %u", conn->sco_rx_ms);
2743                 sco_schedule_tx(conn);
2744             }
2745         }
2746     }
2747     // deliver to app
2748     if (hci_stack->sco_packet_handler) {
2749         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2750     }
2751 
2752 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2753     conn->num_packets_completed++;
2754     hci_stack->host_completed_packets = 1;
2755     hci_run();
2756 #endif
2757 }
2758 #endif
2759 
2760 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2761     hci_dump_packet(packet_type, 1, packet, size);
2762     switch (packet_type) {
2763         case HCI_EVENT_PACKET:
2764             event_handler(packet, size);
2765             break;
2766         case HCI_ACL_DATA_PACKET:
2767             acl_handler(packet, size);
2768             break;
2769 #ifdef ENABLE_CLASSIC
2770         case HCI_SCO_DATA_PACKET:
2771             sco_handler(packet, size);
2772             break;
2773 #endif
2774         default:
2775             break;
2776     }
2777 }
2778 
2779 /**
2780  * @brief Add event packet handler.
2781  */
2782 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2783     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2784 }
2785 
2786 
2787 /** Register HCI packet handlers */
2788 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2789     hci_stack->acl_packet_handler = handler;
2790 }
2791 
2792 #ifdef ENABLE_CLASSIC
2793 /**
2794  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2795  */
2796 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2797     hci_stack->sco_packet_handler = handler;
2798 }
2799 #endif
2800 
2801 static void hci_state_reset(void){
2802     // no connections yet
2803     hci_stack->connections = NULL;
2804 
2805     // keep discoverable/connectable as this has been requested by the client(s)
2806     // hci_stack->discoverable = 0;
2807     // hci_stack->connectable = 0;
2808     // hci_stack->bondable = 1;
2809     // hci_stack->own_addr_type = 0;
2810 
2811     // buffer is free
2812     hci_stack->hci_packet_buffer_reserved = 0;
2813 
2814     // no pending cmds
2815     hci_stack->decline_reason = 0;
2816     hci_stack->new_scan_enable_value = 0xff;
2817 
2818     // LE
2819 #ifdef ENABLE_BLE
2820     memset(hci_stack->le_random_address, 0, 6);
2821     hci_stack->le_random_address_set = 0;
2822 #endif
2823 #ifdef ENABLE_LE_CENTRAL
2824     hci_stack->le_scanning_active  = 0;
2825     hci_stack->le_scan_type = 0xff;
2826     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2827     hci_stack->le_whitelist = 0;
2828     hci_stack->le_whitelist_capacity = 0;
2829 #endif
2830 }
2831 
2832 #ifdef ENABLE_CLASSIC
2833 /**
2834  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2835  */
2836 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2837     // store and open remote device db
2838     hci_stack->link_key_db = link_key_db;
2839     if (hci_stack->link_key_db) {
2840         hci_stack->link_key_db->open();
2841     }
2842 }
2843 #endif
2844 
2845 void hci_init(const hci_transport_t *transport, const void *config){
2846 
2847 #ifdef HAVE_MALLOC
2848     if (!hci_stack) {
2849         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2850     }
2851 #else
2852     hci_stack = &hci_stack_static;
2853 #endif
2854     memset(hci_stack, 0, sizeof(hci_stack_t));
2855 
2856     // reference to use transport layer implementation
2857     hci_stack->hci_transport = transport;
2858 
2859     // reference to used config
2860     hci_stack->config = config;
2861 
2862     // setup pointer for outgoing packet buffer
2863     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2864 
2865     // max acl payload size defined in config.h
2866     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2867 
2868     // register packet handlers with transport
2869     transport->register_packet_handler(&packet_handler);
2870 
2871     hci_stack->state = HCI_STATE_OFF;
2872 
2873     // class of device
2874     hci_stack->class_of_device = 0x007a020c; // Smartphone
2875 
2876     // bondable by default
2877     hci_stack->bondable = 1;
2878 
2879 #ifdef ENABLE_CLASSIC
2880     // classic name
2881     hci_stack->local_name = default_classic_name;
2882 
2883     // Master slave policy
2884     hci_stack->master_slave_policy = 1;
2885 
2886     // Allow Role Switch
2887     hci_stack->allow_role_switch = 1;
2888 
2889     // Default / minimum security level = 2
2890     hci_stack->gap_security_level = LEVEL_2;
2891 
2892     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2893     hci_stack->gap_required_encyrption_key_size = 16;
2894 #endif
2895 
2896     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2897     hci_stack->ssp_enable = 1;
2898     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2899     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2900     hci_stack->ssp_auto_accept = 1;
2901 
2902     // voice setting - signed 16 bit pcm data with CVSD over the air
2903     hci_stack->sco_voice_setting = 0x60;
2904 
2905 #ifdef ENABLE_LE_CENTRAL
2906     // connection parameter to use for outgoing connections
2907     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2908     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2909     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2910     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2911     hci_stack->le_connection_latency      = 4;         // 4
2912     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2913     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2914     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2915 
2916     // default LE Scanning
2917     hci_stack->le_scan_interval = 0x1e0;
2918     hci_stack->le_scan_window   =  0x30;
2919 #endif
2920 
2921 #ifdef ENABLE_LE_PERIPHERAL
2922     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2923 #endif
2924 
2925     // connection parameter range used to answer connection parameter update requests in l2cap
2926     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2927     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2928     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2929     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2930     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2931     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2932 
2933     hci_state_reset();
2934 }
2935 
2936 /**
2937  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2938  */
2939 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2940     hci_stack->chipset = chipset_driver;
2941 
2942     // reset chipset driver - init is also called on power_up
2943     if (hci_stack->chipset && hci_stack->chipset->init){
2944         hci_stack->chipset->init(hci_stack->config);
2945     }
2946 }
2947 
2948 /**
2949  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2950  */
2951 void hci_set_control(const btstack_control_t *hardware_control){
2952     // references to used control implementation
2953     hci_stack->control = hardware_control;
2954     // init with transport config
2955     hardware_control->init(hci_stack->config);
2956 }
2957 
2958 void hci_close(void){
2959     // close remote device db
2960     if (hci_stack->link_key_db) {
2961         hci_stack->link_key_db->close();
2962     }
2963 
2964     btstack_linked_list_iterator_t lit;
2965     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2966     while (btstack_linked_list_iterator_has_next(&lit)){
2967         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2968         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2969         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2970         hci_shutdown_connection(connection);
2971     }
2972 
2973     hci_power_control(HCI_POWER_OFF);
2974 
2975 #ifdef HAVE_MALLOC
2976     free(hci_stack);
2977 #endif
2978     hci_stack = NULL;
2979 }
2980 
2981 #ifdef ENABLE_CLASSIC
2982 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
2983     // validate ranage and set
2984     if (encryption_key_size < 7)  return;
2985     if (encryption_key_size > 16) return;
2986     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
2987 }
2988 
2989 void gap_set_security_level(gap_security_level_t security_level){
2990     hci_stack->gap_security_level = security_level;
2991 }
2992 
2993 gap_security_level_t gap_get_security_level(void){
2994     return hci_stack->gap_security_level;
2995 }
2996 #endif
2997 
2998 #ifdef ENABLE_CLASSIC
2999 void gap_set_class_of_device(uint32_t class_of_device){
3000     hci_stack->class_of_device = class_of_device;
3001 }
3002 
3003 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3004     hci_stack->default_link_policy_settings = default_link_policy_settings;
3005 }
3006 
3007 void gap_set_allow_role_switch(bool allow_role_switch){
3008     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3009 }
3010 
3011 uint8_t hci_get_allow_role_switch(void){
3012     return  hci_stack->allow_role_switch;
3013 }
3014 
3015 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3016     hci_stack->link_supervision_timeout = link_supervision_timeout;
3017 }
3018 
3019 void hci_disable_l2cap_timeout_check(void){
3020     disable_l2cap_timeouts = 1;
3021 }
3022 #endif
3023 
3024 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3025 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3026 void hci_set_bd_addr(bd_addr_t addr){
3027     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3028     hci_stack->custom_bd_addr_set = 1;
3029 }
3030 #endif
3031 
3032 // State-Module-Driver overview
3033 // state                    module  low-level
3034 // HCI_STATE_OFF             off      close
3035 // HCI_STATE_INITIALIZING,   on       open
3036 // HCI_STATE_WORKING,        on       open
3037 // HCI_STATE_HALTING,        on       open
3038 // HCI_STATE_SLEEPING,    off/sleep   close
3039 // HCI_STATE_FALLING_ASLEEP  on       open
3040 
3041 static int hci_power_control_on(void){
3042 
3043     // power on
3044     int err = 0;
3045     if (hci_stack->control && hci_stack->control->on){
3046         err = (*hci_stack->control->on)();
3047     }
3048     if (err){
3049         log_error( "POWER_ON failed");
3050         hci_emit_hci_open_failed();
3051         return err;
3052     }
3053 
3054     // int chipset driver
3055     if (hci_stack->chipset && hci_stack->chipset->init){
3056         hci_stack->chipset->init(hci_stack->config);
3057     }
3058 
3059     // init transport
3060     if (hci_stack->hci_transport->init){
3061         hci_stack->hci_transport->init(hci_stack->config);
3062     }
3063 
3064     // open transport
3065     err = hci_stack->hci_transport->open();
3066     if (err){
3067         log_error( "HCI_INIT failed, turning Bluetooth off again");
3068         if (hci_stack->control && hci_stack->control->off){
3069             (*hci_stack->control->off)();
3070         }
3071         hci_emit_hci_open_failed();
3072         return err;
3073     }
3074     return 0;
3075 }
3076 
3077 static void hci_power_control_off(void){
3078 
3079     log_info("hci_power_control_off");
3080 
3081     // close low-level device
3082     hci_stack->hci_transport->close();
3083 
3084     log_info("hci_power_control_off - hci_transport closed");
3085 
3086     // power off
3087     if (hci_stack->control && hci_stack->control->off){
3088         (*hci_stack->control->off)();
3089     }
3090 
3091     log_info("hci_power_control_off - control closed");
3092 
3093     hci_stack->state = HCI_STATE_OFF;
3094 }
3095 
3096 static void hci_power_control_sleep(void){
3097 
3098     log_info("hci_power_control_sleep");
3099 
3100 #if 0
3101     // don't close serial port during sleep
3102 
3103     // close low-level device
3104     hci_stack->hci_transport->close(hci_stack->config);
3105 #endif
3106 
3107     // sleep mode
3108     if (hci_stack->control && hci_stack->control->sleep){
3109         (*hci_stack->control->sleep)();
3110     }
3111 
3112     hci_stack->state = HCI_STATE_SLEEPING;
3113 }
3114 
3115 static int hci_power_control_wake(void){
3116 
3117     log_info("hci_power_control_wake");
3118 
3119     // wake on
3120     if (hci_stack->control && hci_stack->control->wake){
3121         (*hci_stack->control->wake)();
3122     }
3123 
3124 #if 0
3125     // open low-level device
3126     int err = hci_stack->hci_transport->open(hci_stack->config);
3127     if (err){
3128         log_error( "HCI_INIT failed, turning Bluetooth off again");
3129         if (hci_stack->control && hci_stack->control->off){
3130             (*hci_stack->control->off)();
3131         }
3132         hci_emit_hci_open_failed();
3133         return err;
3134     }
3135 #endif
3136 
3137     return 0;
3138 }
3139 
3140 static void hci_power_transition_to_initializing(void){
3141     // set up state machine
3142     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3143     hci_stack->hci_packet_buffer_reserved = 0;
3144     hci_stack->state = HCI_STATE_INITIALIZING;
3145     hci_stack->substate = HCI_INIT_SEND_RESET;
3146 }
3147 
3148 int hci_power_control(HCI_POWER_MODE power_mode){
3149 
3150     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3151 
3152     int err = 0;
3153     switch (hci_stack->state){
3154 
3155         case HCI_STATE_OFF:
3156             switch (power_mode){
3157                 case HCI_POWER_ON:
3158                     err = hci_power_control_on();
3159                     if (err) {
3160                         log_error("hci_power_control_on() error %d", err);
3161                         return err;
3162                     }
3163                     hci_power_transition_to_initializing();
3164                     break;
3165                 case HCI_POWER_OFF:
3166                     // do nothing
3167                     break;
3168                 case HCI_POWER_SLEEP:
3169                     // do nothing (with SLEEP == OFF)
3170                     break;
3171             }
3172             break;
3173 
3174         case HCI_STATE_INITIALIZING:
3175             switch (power_mode){
3176                 case HCI_POWER_ON:
3177                     // do nothing
3178                     break;
3179                 case HCI_POWER_OFF:
3180                     // no connections yet, just turn it off
3181                     hci_power_control_off();
3182                     break;
3183                 case HCI_POWER_SLEEP:
3184                     // no connections yet, just turn it off
3185                     hci_power_control_sleep();
3186                     break;
3187             }
3188             break;
3189 
3190         case HCI_STATE_WORKING:
3191             switch (power_mode){
3192                 case HCI_POWER_ON:
3193                     // do nothing
3194                     break;
3195                 case HCI_POWER_OFF:
3196                     // see hci_run
3197                     hci_stack->state = HCI_STATE_HALTING;
3198                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3199                     break;
3200                 case HCI_POWER_SLEEP:
3201                     // see hci_run
3202                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3203                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3204                     break;
3205             }
3206             break;
3207 
3208         case HCI_STATE_HALTING:
3209             switch (power_mode){
3210                 case HCI_POWER_ON:
3211                     hci_power_transition_to_initializing();
3212                     break;
3213                 case HCI_POWER_OFF:
3214                     // do nothing
3215                     break;
3216                 case HCI_POWER_SLEEP:
3217                     // see hci_run
3218                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3219                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3220                     break;
3221             }
3222             break;
3223 
3224         case HCI_STATE_FALLING_ASLEEP:
3225             switch (power_mode){
3226                 case HCI_POWER_ON:
3227 
3228 #ifdef HAVE_PLATFORM_IPHONE_OS
3229                     // nothing to do, if H4 supports power management
3230                     if (btstack_control_iphone_power_management_enabled()){
3231                         hci_stack->state = HCI_STATE_INITIALIZING;
3232                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3233                         break;
3234                     }
3235 #endif
3236                     hci_power_transition_to_initializing();
3237                     break;
3238                 case HCI_POWER_OFF:
3239                     // see hci_run
3240                     hci_stack->state = HCI_STATE_HALTING;
3241                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3242                     break;
3243                 case HCI_POWER_SLEEP:
3244                     // do nothing
3245                     break;
3246             }
3247             break;
3248 
3249         case HCI_STATE_SLEEPING:
3250             switch (power_mode){
3251                 case HCI_POWER_ON:
3252 
3253 #ifdef HAVE_PLATFORM_IPHONE_OS
3254                     // nothing to do, if H4 supports power management
3255                     if (btstack_control_iphone_power_management_enabled()){
3256                         hci_stack->state = HCI_STATE_INITIALIZING;
3257                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3258                         hci_update_scan_enable();
3259                         break;
3260                     }
3261 #endif
3262                     err = hci_power_control_wake();
3263                     if (err) return err;
3264                     hci_power_transition_to_initializing();
3265                     break;
3266                 case HCI_POWER_OFF:
3267                     hci_stack->state = HCI_STATE_HALTING;
3268                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3269                     break;
3270                 case HCI_POWER_SLEEP:
3271                     // do nothing
3272                     break;
3273             }
3274             break;
3275     }
3276 
3277     // create internal event
3278 	hci_emit_state();
3279 
3280 	// trigger next/first action
3281 	hci_run();
3282 
3283     return 0;
3284 }
3285 
3286 
3287 #ifdef ENABLE_CLASSIC
3288 
3289 static void hci_update_scan_enable(void){
3290     // 2 = page scan, 1 = inq scan
3291     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3292     hci_run();
3293 }
3294 
3295 void gap_discoverable_control(uint8_t enable){
3296     if (enable) enable = 1; // normalize argument
3297 
3298     if (hci_stack->discoverable == enable){
3299         hci_emit_discoverable_enabled(hci_stack->discoverable);
3300         return;
3301     }
3302 
3303     hci_stack->discoverable = enable;
3304     hci_update_scan_enable();
3305 }
3306 
3307 void gap_connectable_control(uint8_t enable){
3308     if (enable) enable = 1; // normalize argument
3309 
3310     // don't emit event
3311     if (hci_stack->connectable == enable) return;
3312 
3313     hci_stack->connectable = enable;
3314     hci_update_scan_enable();
3315 }
3316 #endif
3317 
3318 void gap_local_bd_addr(bd_addr_t address_buffer){
3319     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3320 }
3321 
3322 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3323 static void hci_host_num_completed_packets(void){
3324 
3325     // create packet manually as arrays are not supported and num_commands should not get reduced
3326     hci_reserve_packet_buffer();
3327     uint8_t * packet = hci_get_outgoing_packet_buffer();
3328 
3329     uint16_t size = 0;
3330     uint16_t num_handles = 0;
3331     packet[size++] = 0x35;
3332     packet[size++] = 0x0c;
3333     size++;  // skip param len
3334     size++;  // skip num handles
3335 
3336     // add { handle, packets } entries
3337     btstack_linked_item_t * it;
3338     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3339         hci_connection_t * connection = (hci_connection_t *) it;
3340         if (connection->num_packets_completed){
3341             little_endian_store_16(packet, size, connection->con_handle);
3342             size += 2;
3343             little_endian_store_16(packet, size, connection->num_packets_completed);
3344             size += 2;
3345             //
3346             num_handles++;
3347             connection->num_packets_completed = 0;
3348         }
3349     }
3350 
3351     packet[2] = size - 3;
3352     packet[3] = num_handles;
3353 
3354     hci_stack->host_completed_packets = 0;
3355 
3356     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3357     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3358 
3359     // release packet buffer for synchronous transport implementations
3360     if (hci_transport_synchronous()){
3361         hci_release_packet_buffer();
3362         hci_emit_transport_packet_sent();
3363     }
3364 }
3365 #endif
3366 
3367 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3368     UNUSED(ds);
3369     hci_stack->substate = HCI_HALTING_CLOSE;
3370     // allow packet handlers to defer final shutdown
3371     hci_emit_state();
3372     hci_run();
3373 }
3374 
3375 static bool hci_run_acl_fragments(void){
3376     if (hci_stack->acl_fragmentation_total_size > 0) {
3377         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3378         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3379         if (connection) {
3380             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3381                 hci_send_acl_packet_fragments(connection);
3382                 return true;
3383             }
3384         } else {
3385             // connection gone -> discard further fragments
3386             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3387             hci_stack->acl_fragmentation_total_size = 0;
3388             hci_stack->acl_fragmentation_pos = 0;
3389         }
3390     }
3391     return false;
3392 }
3393 
3394 #ifdef ENABLE_CLASSIC
3395 static bool hci_run_general_gap_classic(void){
3396 
3397     // decline incoming connections
3398     if (hci_stack->decline_reason){
3399         uint8_t reason = hci_stack->decline_reason;
3400         hci_stack->decline_reason = 0;
3401         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3402         return true;
3403     }
3404     // send scan enable
3405     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3406         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3407         hci_stack->new_scan_enable_value = 0xff;
3408         return true;
3409     }
3410     // start/stop inquiry
3411     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3412         uint8_t duration = hci_stack->inquiry_state;
3413         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3414         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3415         return true;
3416     }
3417     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3418         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3419         hci_send_cmd(&hci_inquiry_cancel);
3420         return true;
3421     }
3422     // remote name request
3423     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3424         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3425         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3426                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3427         return true;
3428     }
3429     // pairing
3430     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3431         uint8_t state = hci_stack->gap_pairing_state;
3432         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3433         switch (state){
3434             case GAP_PAIRING_STATE_SEND_PIN:
3435                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, strlen(hci_stack->gap_pairing_input.gap_pairing_pin), hci_stack->gap_pairing_input.gap_pairing_pin);
3436                 break;
3437             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3438                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3439                 break;
3440             case GAP_PAIRING_STATE_SEND_PASSKEY:
3441                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3442                 break;
3443             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3444                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3445                 break;
3446             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3447                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3448                 break;
3449             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3450                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3451                 break;
3452             default:
3453                 break;
3454         }
3455         return true;
3456     }
3457     return false;
3458 }
3459 #endif
3460 
3461 #ifdef ENABLE_BLE
3462 static bool hci_run_general_gap_le(void){
3463 
3464     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3465 
3466     if (hci_stack->state != HCI_STATE_WORKING) return false;
3467     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3468 
3469 #ifdef ENABLE_LE_CENTRAL
3470     // parameter change requires scanning to be stopped first
3471     if (hci_stack->le_scan_type != 0xff) {
3472         if (hci_stack->le_scanning_active){
3473             hci_stack->le_scanning_active = 0;
3474             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3475         } else {
3476             int scan_type = (int) hci_stack->le_scan_type;
3477             hci_stack->le_scan_type = 0xff;
3478             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
3479         }
3480         return true;
3481     }
3482     // finally, we can enable/disable le scan
3483     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3484         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3485         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3486         return true;
3487     }
3488 #endif
3489 #ifdef ENABLE_LE_PERIPHERAL
3490     // le advertisement control
3491     if (hci_stack->le_advertisements_todo){
3492         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3493     }
3494     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3495         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3496         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3497         return true;
3498     }
3499     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3500         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3501         hci_send_cmd(&hci_le_set_advertising_parameters,
3502                      hci_stack->le_advertisements_interval_min,
3503                      hci_stack->le_advertisements_interval_max,
3504                      hci_stack->le_advertisements_type,
3505                      hci_stack->le_own_addr_type,
3506                      hci_stack->le_advertisements_direct_address_type,
3507                      hci_stack->le_advertisements_direct_address,
3508                      hci_stack->le_advertisements_channel_map,
3509                      hci_stack->le_advertisements_filter_policy);
3510         return true;
3511     }
3512     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3513         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3514         uint8_t adv_data_clean[31];
3515         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3516         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3517                      hci_stack->le_advertisements_data_len);
3518         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3519         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3520         return true;
3521     }
3522     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3523         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3524         uint8_t scan_data_clean[31];
3525         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3526         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3527                      hci_stack->le_scan_response_data_len);
3528         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3529         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3530         return true;
3531     }
3532     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3533         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3534         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3535         return true;
3536     }
3537 #endif
3538 
3539 #ifdef ENABLE_LE_CENTRAL
3540     //
3541     // LE Whitelist Management
3542     //
3543 
3544     // check if whitelist needs modification
3545     btstack_linked_list_iterator_t lit;
3546     int modification_pending = 0;
3547     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3548     while (btstack_linked_list_iterator_has_next(&lit)){
3549         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3550         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3551             modification_pending = 1;
3552             break;
3553         }
3554     }
3555 
3556     if (modification_pending){
3557         // stop connnecting if modification pending
3558         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3559             hci_send_cmd(&hci_le_create_connection_cancel);
3560             return true;
3561         }
3562 
3563         // add/remove entries
3564         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3565         while (btstack_linked_list_iterator_has_next(&lit)){
3566             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3567             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3568                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3569                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3570                 return true;
3571             }
3572             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3573                 bd_addr_t address;
3574                 bd_addr_type_t address_type = entry->address_type;
3575                 (void)memcpy(address, entry->address, 6);
3576                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3577                 btstack_memory_whitelist_entry_free(entry);
3578                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3579                 return true;
3580             }
3581         }
3582     }
3583 
3584     // start connecting
3585     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3586          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3587         bd_addr_t null_addr;
3588         memset(null_addr, 0, 6);
3589         hci_send_cmd(&hci_le_create_connection,
3590                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3591                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3592                      1,         // use whitelist
3593                      0,         // peer address type
3594                      null_addr, // peer bd addr
3595                      hci_stack->le_own_addr_type, // our addr type:
3596                      hci_stack->le_connection_interval_min,    // conn interval min
3597                      hci_stack->le_connection_interval_max,    // conn interval max
3598                      hci_stack->le_connection_latency,         // conn latency
3599                      hci_stack->le_supervision_timeout,        // conn latency
3600                      hci_stack->le_minimum_ce_length,          // min ce length
3601                      hci_stack->le_maximum_ce_length           // max ce length
3602         );
3603         return true;
3604     }
3605 #endif
3606     return false;
3607 }
3608 #endif
3609 
3610 static bool hci_run_general_pending_commmands(void){
3611     btstack_linked_item_t * it;
3612     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3613         hci_connection_t * connection = (hci_connection_t *) it;
3614 
3615         switch(connection->state){
3616             case SEND_CREATE_CONNECTION:
3617                 switch(connection->address_type){
3618 #ifdef ENABLE_CLASSIC
3619                     case BD_ADDR_TYPE_ACL:
3620                         log_info("sending hci_create_connection");
3621                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3622                         break;
3623 #endif
3624                     default:
3625 #ifdef ENABLE_BLE
3626 #ifdef ENABLE_LE_CENTRAL
3627                         // track outgoing connection
3628                         hci_stack->outgoing_addr_type = connection->address_type;
3629                         (void)memcpy(hci_stack->outgoing_addr,
3630                                      connection->address, 6);
3631                         log_info("sending hci_le_create_connection");
3632                         hci_send_cmd(&hci_le_create_connection,
3633                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3634                                      hci_stack->le_connection_scan_window,      // conn scan windows
3635                                      0,         // don't use whitelist
3636                                      connection->address_type, // peer address type
3637                                      connection->address,      // peer bd addr
3638                                      hci_stack->le_own_addr_type, // our addr type:
3639                                      hci_stack->le_connection_interval_min,    // conn interval min
3640                                      hci_stack->le_connection_interval_max,    // conn interval max
3641                                      hci_stack->le_connection_latency,         // conn latency
3642                                      hci_stack->le_supervision_timeout,        // conn latency
3643                                      hci_stack->le_minimum_ce_length,          // min ce length
3644                                      hci_stack->le_maximum_ce_length          // max ce length
3645                         );
3646                         connection->state = SENT_CREATE_CONNECTION;
3647 #endif
3648 #endif
3649                         break;
3650                 }
3651                 return true;
3652 
3653 #ifdef ENABLE_CLASSIC
3654             case RECEIVED_CONNECTION_REQUEST:
3655                 connection->role  = HCI_ROLE_SLAVE;
3656                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3657                     log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
3658                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3659                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3660                 }
3661                 return true;
3662 #endif
3663 
3664 #ifdef ENABLE_BLE
3665 #ifdef ENABLE_LE_CENTRAL
3666             case SEND_CANCEL_CONNECTION:
3667                 connection->state = SENT_CANCEL_CONNECTION;
3668                 hci_send_cmd(&hci_le_create_connection_cancel);
3669                 return true;
3670 #endif
3671 #endif
3672             case SEND_DISCONNECT:
3673                 connection->state = SENT_DISCONNECT;
3674                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3675                 return true;
3676 
3677             default:
3678                 break;
3679         }
3680 
3681         // no further commands if connection is about to get shut down
3682         if (connection->state == SENT_DISCONNECT) continue;
3683 
3684         if (connection->authentication_flags & READ_RSSI){
3685             connectionClearAuthenticationFlags(connection, READ_RSSI);
3686             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3687             return true;
3688         }
3689 
3690 #ifdef ENABLE_CLASSIC
3691 
3692         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3693             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3694             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3695             return true;
3696         }
3697 
3698         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3699             log_info("responding to link key request");
3700             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3701             link_key_t link_key;
3702             link_key_type_t link_key_type;
3703             if ( hci_stack->link_key_db
3704                  && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3705                  && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level)){
3706                 connection->link_key_type = link_key_type;
3707                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3708             } else {
3709                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3710             }
3711             return true;
3712         }
3713 
3714         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3715             log_info("denying to pin request");
3716             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3717             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3718             return true;
3719         }
3720 
3721         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3722             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3723             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3724             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3725                 // tweak authentication requirements
3726                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3727                 if (connection->bonding_flags & BONDING_DEDICATED){
3728                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3729                 }
3730                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3731                     authreq |= 1;
3732                 }
3733                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3734             } else {
3735                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3736             }
3737             return true;
3738         }
3739 
3740         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3741             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3742             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3743             return true;
3744         }
3745 
3746         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3747             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3748             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3749             return true;
3750         }
3751 
3752         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
3753             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
3754             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3755             return true;
3756         }
3757 
3758         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3759             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3760             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3761             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3762             return true;
3763         }
3764 
3765         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3766             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3767             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3768             return true;
3769         }
3770 
3771         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3772             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3773             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3774             return true;
3775         }
3776         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3777             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3778             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3779             return true;
3780         }
3781 #endif
3782 
3783         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3784             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3785             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3786             return true;
3787         }
3788 
3789 #ifdef ENABLE_CLASSIC
3790         uint16_t sniff_min_interval;
3791         switch (connection->sniff_min_interval){
3792             case 0:
3793                 break;
3794             case 0xffff:
3795                 connection->sniff_min_interval = 0;
3796                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3797                 return true;
3798             default:
3799                 sniff_min_interval = connection->sniff_min_interval;
3800                 connection->sniff_min_interval = 0;
3801                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3802                 return true;
3803         }
3804 #endif
3805 
3806 #ifdef ENABLE_BLE
3807         switch (connection->le_con_parameter_update_state){
3808             // response to L2CAP CON PARAMETER UPDATE REQUEST
3809             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3810                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3811                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3812                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3813                              0x0000, 0xffff);
3814                 return true;
3815             case CON_PARAMETER_UPDATE_REPLY:
3816                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3817                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3818                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3819                              0x0000, 0xffff);
3820                 return true;
3821             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3822                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3823                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3824                 return true;
3825             default:
3826                 break;
3827         }
3828         if (connection->le_phy_update_all_phys != 0xff){
3829             uint8_t all_phys = connection->le_phy_update_all_phys;
3830             connection->le_phy_update_all_phys = 0xff;
3831             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);
3832             return true;
3833         }
3834 #endif
3835     }
3836     return false;
3837 }
3838 
3839 static void hci_run(void){
3840 
3841     bool done;
3842 
3843     // send continuation fragments first, as they block the prepared packet buffer
3844     done = hci_run_acl_fragments();
3845     if (done) return;
3846 
3847 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3848     // send host num completed packets next as they don't require num_cmd_packets > 0
3849     if (!hci_can_send_comand_packet_transport()) return;
3850     if (hci_stack->host_completed_packets){
3851         hci_host_num_completed_packets();
3852         return;
3853     }
3854 #endif
3855 
3856     if (!hci_can_send_command_packet_now()) return;
3857 
3858     // global/non-connection oriented commands
3859 
3860 
3861 #ifdef ENABLE_CLASSIC
3862     // general gap classic
3863     done = hci_run_general_gap_classic();
3864     if (done) return;
3865 #endif
3866 
3867 #ifdef ENABLE_BLE
3868     // general gap le
3869     done = hci_run_general_gap_le();
3870     if (done) return;
3871 #endif
3872 
3873     // send pending HCI commands
3874     done = hci_run_general_pending_commmands();
3875     if (done) return;
3876 
3877     // stack state sub statemachines
3878     hci_connection_t * connection;
3879     switch (hci_stack->state){
3880         case HCI_STATE_INITIALIZING:
3881             hci_initializing_run();
3882             break;
3883 
3884         case HCI_STATE_HALTING:
3885 
3886             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3887             switch (hci_stack->substate){
3888                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3889                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3890 
3891 #ifdef ENABLE_BLE
3892 #ifdef ENABLE_LE_CENTRAL
3893                     // free whitelist entries
3894                     {
3895                         btstack_linked_list_iterator_t lit;
3896                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3897                         while (btstack_linked_list_iterator_has_next(&lit)){
3898                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3899                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3900                             btstack_memory_whitelist_entry_free(entry);
3901                         }
3902                     }
3903 #endif
3904 #endif
3905                     // close all open connections
3906                     connection =  (hci_connection_t *) hci_stack->connections;
3907                     if (connection){
3908                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3909                         if (!hci_can_send_command_packet_now()) return;
3910 
3911                         // check state
3912                         if (connection->state == SENT_DISCONNECT) return;
3913                         connection->state = SENT_DISCONNECT;
3914 
3915                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3916 
3917                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3918                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3919 
3920                         // ... which would be ignored anyway as we shutdown (free) the connection now
3921                         hci_shutdown_connection(connection);
3922 
3923                         // finally, send the disconnect command
3924                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3925                         return;
3926                     }
3927 
3928                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
3929                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
3930                         log_info("HCI_STATE_HALTING: wait 50 ms");
3931                         hci_stack->substate = HCI_HALTING_W4_TIMER;
3932                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
3933                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3934                         btstack_run_loop_add_timer(&hci_stack->timeout);
3935                         break;
3936                     }
3937 
3938                     /* fall through */
3939 
3940                 case HCI_HALTING_CLOSE:
3941                     log_info("HCI_STATE_HALTING, calling off");
3942 
3943                     // switch mode
3944                     hci_power_control_off();
3945 
3946                     log_info("HCI_STATE_HALTING, emitting state");
3947                     hci_emit_state();
3948                     log_info("HCI_STATE_HALTING, done");
3949                     break;
3950 
3951                 case HCI_HALTING_W4_TIMER:
3952                     // keep waiting
3953 
3954                     break;
3955                 default:
3956                     break;
3957             }
3958 
3959             break;
3960 
3961         case HCI_STATE_FALLING_ASLEEP:
3962             switch(hci_stack->substate) {
3963                 case HCI_FALLING_ASLEEP_DISCONNECT:
3964                     log_info("HCI_STATE_FALLING_ASLEEP");
3965                     // close all open connections
3966                     connection =  (hci_connection_t *) hci_stack->connections;
3967 
3968 #ifdef HAVE_PLATFORM_IPHONE_OS
3969                     // don't close connections, if H4 supports power management
3970                     if (btstack_control_iphone_power_management_enabled()){
3971                         connection = NULL;
3972                     }
3973 #endif
3974                     if (connection){
3975 
3976                         // send disconnect
3977                         if (!hci_can_send_command_packet_now()) return;
3978 
3979                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
3980                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
3981 
3982                         // send disconnected event right away - causes higher layer connections to get closed, too.
3983                         hci_shutdown_connection(connection);
3984                         return;
3985                     }
3986 
3987                     if (hci_classic_supported()){
3988                         // disable page and inquiry scan
3989                         if (!hci_can_send_command_packet_now()) return;
3990 
3991                         log_info("HCI_STATE_HALTING, disabling inq scans");
3992                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
3993 
3994                         // continue in next sub state
3995                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
3996                         break;
3997                     }
3998 
3999                     /* fall through */
4000 
4001                 case HCI_FALLING_ASLEEP_COMPLETE:
4002                     log_info("HCI_STATE_HALTING, calling sleep");
4003 #ifdef HAVE_PLATFORM_IPHONE_OS
4004                     // don't actually go to sleep, if H4 supports power management
4005                     if (btstack_control_iphone_power_management_enabled()){
4006                         // SLEEP MODE reached
4007                         hci_stack->state = HCI_STATE_SLEEPING;
4008                         hci_emit_state();
4009                         break;
4010                     }
4011 #endif
4012                     // switch mode
4013                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4014                     hci_emit_state();
4015                     break;
4016 
4017                 default:
4018                     break;
4019             }
4020             break;
4021 
4022         default:
4023             break;
4024     }
4025 }
4026 
4027 int hci_send_cmd_packet(uint8_t *packet, int size){
4028     // house-keeping
4029 
4030     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4031         hci_stack->loopback_mode = packet[3];
4032     }
4033 
4034 #ifdef ENABLE_CLASSIC
4035     bd_addr_t addr;
4036     hci_connection_t * conn;
4037 
4038     // create_connection?
4039     if (IS_COMMAND(packet, hci_create_connection)){
4040         reverse_bd_addr(&packet[3], addr);
4041         log_info("Create_connection to %s", bd_addr_to_str(addr));
4042 
4043         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4044         if (!conn){
4045             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4046             if (!conn){
4047                 // notify client that alloc failed
4048                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4049                 return -1; // packet not sent to controller
4050             }
4051             conn->state = SEND_CREATE_CONNECTION;
4052         }
4053         log_info("conn state %u", conn->state);
4054         switch (conn->state){
4055             // if connection active exists
4056             case OPEN:
4057                 // and OPEN, emit connection complete command
4058                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4059                 return -1; // packet not sent to controller
4060             case RECEIVED_DISCONNECTION_COMPLETE:
4061                 // create connection triggered in disconnect complete event, let's do it now
4062                 break;
4063             case SEND_CREATE_CONNECTION:
4064                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4065                 break;
4066             default:
4067                 // otherwise, just ignore as it is already in the open process
4068                 return -1; // packet not sent to controller
4069         }
4070         conn->state = SENT_CREATE_CONNECTION;
4071 
4072         // track outgoing connection
4073         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4074         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4075     }
4076 
4077     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4078         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4079     }
4080     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4081         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4082     }
4083 
4084     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4085         if (hci_stack->link_key_db){
4086             reverse_bd_addr(&packet[3], addr);
4087             hci_stack->link_key_db->delete_link_key(addr);
4088         }
4089     }
4090 
4091     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4092     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4093         reverse_bd_addr(&packet[3], addr);
4094         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4095         if (conn){
4096             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4097         }
4098     }
4099 
4100     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4101     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4102     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4103     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4104         reverse_bd_addr(&packet[3], addr);
4105         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4106         if (conn){
4107             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4108         }
4109     }
4110 
4111 #ifdef ENABLE_SCO_OVER_HCI
4112     // setup_synchronous_connection? Voice setting at offset 22
4113     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4114         // TODO: compare to current setting if sco connection already active
4115         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4116     }
4117     // accept_synchronus_connection? Voice setting at offset 18
4118     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4119         // TODO: compare to current setting if sco connection already active
4120         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4121     }
4122 #endif
4123 #endif
4124 
4125 #ifdef ENABLE_BLE
4126     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4127         hci_stack->le_random_address_set = 1;
4128         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4129     }
4130 #ifdef ENABLE_LE_PERIPHERAL
4131     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4132         hci_stack->le_advertisements_active = packet[3];
4133     }
4134 #endif
4135 #ifdef ENABLE_LE_CENTRAL
4136     else if (IS_COMMAND(packet, hci_le_create_connection)){
4137         // white list used?
4138         uint8_t initiator_filter_policy = packet[7];
4139         switch (initiator_filter_policy){
4140             case 0:
4141                 // whitelist not used
4142                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4143                 break;
4144             case 1:
4145                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4146                 break;
4147             default:
4148                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4149                 break;
4150         }
4151     }
4152     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4153         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4154     }
4155 #endif
4156 #endif
4157 
4158     hci_stack->num_cmd_packets--;
4159 
4160     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4161     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4162 }
4163 
4164 // disconnect because of security block
4165 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4166     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4167     if (!connection) return;
4168     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4169 }
4170 
4171 
4172 // Configure Secure Simple Pairing
4173 
4174 #ifdef ENABLE_CLASSIC
4175 
4176 // enable will enable SSP during init
4177 void gap_ssp_set_enable(int enable){
4178     hci_stack->ssp_enable = enable;
4179 }
4180 
4181 static int hci_local_ssp_activated(void){
4182     return gap_ssp_supported() && hci_stack->ssp_enable;
4183 }
4184 
4185 // if set, BTstack will respond to io capability request using authentication requirement
4186 void gap_ssp_set_io_capability(int io_capability){
4187     hci_stack->ssp_io_capability = io_capability;
4188 }
4189 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4190     hci_stack->ssp_authentication_requirement = authentication_requirement;
4191 }
4192 
4193 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4194 void gap_ssp_set_auto_accept(int auto_accept){
4195     hci_stack->ssp_auto_accept = auto_accept;
4196 }
4197 #endif
4198 
4199 // va_list part of hci_send_cmd
4200 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4201     if (!hci_can_send_command_packet_now()){
4202         log_error("hci_send_cmd called but cannot send packet now");
4203         return 0;
4204     }
4205 
4206     // for HCI INITIALIZATION
4207     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4208     hci_stack->last_cmd_opcode = cmd->opcode;
4209 
4210     hci_reserve_packet_buffer();
4211     uint8_t * packet = hci_stack->hci_packet_buffer;
4212     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4213     int err = hci_send_cmd_packet(packet, size);
4214 
4215     // release packet buffer on error or for synchronous transport implementations
4216     if ((err < 0) || hci_transport_synchronous()){
4217         hci_release_packet_buffer();
4218         hci_emit_transport_packet_sent();
4219     }
4220 
4221     return err;
4222 }
4223 
4224 /**
4225  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4226  */
4227 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4228     va_list argptr;
4229     va_start(argptr, cmd);
4230     int res = hci_send_cmd_va_arg(cmd, argptr);
4231     va_end(argptr);
4232     return res;
4233 }
4234 
4235 // Create various non-HCI events.
4236 // TODO: generalize, use table similar to hci_create_command
4237 
4238 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4239     // dump packet
4240     if (dump) {
4241         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4242     }
4243 
4244     // dispatch to all event handlers
4245     btstack_linked_list_iterator_t it;
4246     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4247     while (btstack_linked_list_iterator_has_next(&it)){
4248         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4249         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4250     }
4251 }
4252 
4253 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4254     if (!hci_stack->acl_packet_handler) return;
4255     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4256 }
4257 
4258 #ifdef ENABLE_CLASSIC
4259 static void hci_notify_if_sco_can_send_now(void){
4260     // notify SCO sender if waiting
4261     if (!hci_stack->sco_waiting_for_can_send_now) return;
4262     if (hci_can_send_sco_packet_now()){
4263         hci_stack->sco_waiting_for_can_send_now = 0;
4264         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4265         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4266         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4267     }
4268 }
4269 
4270 // parsing end emitting has been merged to reduce code size
4271 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4272     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4273 
4274     uint8_t * eir_data;
4275     ad_context_t context;
4276     const uint8_t * name;
4277     uint8_t         name_len;
4278 
4279     if (size < 3) return;
4280 
4281     int event_type = hci_event_packet_get_type(packet);
4282     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4283     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4284 
4285     switch (event_type){
4286         case HCI_EVENT_INQUIRY_RESULT:
4287         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4288             if (size != (3 + (num_responses * 14))) return;
4289             break;
4290         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4291             if (size != 257) return;
4292             if (num_responses != 1) return;
4293             break;
4294         default:
4295             return;
4296     }
4297 
4298     // event[1] is set at the end
4299     int i;
4300     for (i=0; i<num_responses;i++){
4301         memset(event, 0, sizeof(event));
4302         event[0] = GAP_EVENT_INQUIRY_RESULT;
4303         uint8_t event_size = 18;    // if name is not set by EIR
4304 
4305         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4306         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4307         (void)memcpy(&event[9],
4308                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4309                      3); // class of device
4310         (void)memcpy(&event[12],
4311                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4312                      2); // clock offset
4313 
4314         switch (event_type){
4315             case HCI_EVENT_INQUIRY_RESULT:
4316                 // 14,15,16,17 = 0, size 18
4317                 break;
4318             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4319                 event[14] = 1;
4320                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4321                 // 16,17 = 0, size 18
4322                 break;
4323             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4324                 event[14] = 1;
4325                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4326                 // EIR packets only contain a single inquiry response
4327                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4328                 name = NULL;
4329                 // Iterate over EIR data
4330                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4331                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4332                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4333                     const uint8_t * data = ad_iterator_get_data(&context);
4334                     // Prefer Complete Local Name over Shortend Local Name
4335                     switch (data_type){
4336                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4337                             if (name) continue;
4338                             /* fall through */
4339                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4340                             name = data;
4341                             name_len = data_size;
4342                             break;
4343                         default:
4344                             break;
4345                     }
4346                 }
4347                 if (name){
4348                     event[16] = 1;
4349                     // truncate name if needed
4350                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4351                     event[17] = len;
4352                     (void)memcpy(&event[18], name, len);
4353                     event_size += len;
4354                 }
4355                 break;
4356         }
4357         event[1] = event_size - 2;
4358         hci_emit_event(event, event_size, 1);
4359     }
4360 }
4361 #endif
4362 
4363 void hci_emit_state(void){
4364     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4365     uint8_t event[3];
4366     event[0] = BTSTACK_EVENT_STATE;
4367     event[1] = sizeof(event) - 2;
4368     event[2] = hci_stack->state;
4369     hci_emit_event(event, sizeof(event), 1);
4370 }
4371 
4372 #ifdef ENABLE_CLASSIC
4373 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4374     uint8_t event[13];
4375     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4376     event[1] = sizeof(event) - 2;
4377     event[2] = status;
4378     little_endian_store_16(event, 3, con_handle);
4379     reverse_bd_addr(address, &event[5]);
4380     event[11] = 1; // ACL connection
4381     event[12] = 0; // encryption disabled
4382     hci_emit_event(event, sizeof(event), 1);
4383 }
4384 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4385     if (disable_l2cap_timeouts) return;
4386     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4387     uint8_t event[4];
4388     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4389     event[1] = sizeof(event) - 2;
4390     little_endian_store_16(event, 2, conn->con_handle);
4391     hci_emit_event(event, sizeof(event), 1);
4392 }
4393 #endif
4394 
4395 #ifdef ENABLE_BLE
4396 #ifdef ENABLE_LE_CENTRAL
4397 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4398     uint8_t event[21];
4399     event[0] = HCI_EVENT_LE_META;
4400     event[1] = sizeof(event) - 2;
4401     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4402     event[3] = status;
4403     little_endian_store_16(event, 4, con_handle);
4404     event[6] = 0; // TODO: role
4405     event[7] = address_type;
4406     reverse_bd_addr(address, &event[8]);
4407     little_endian_store_16(event, 14, 0); // interval
4408     little_endian_store_16(event, 16, 0); // latency
4409     little_endian_store_16(event, 18, 0); // supervision timeout
4410     event[20] = 0; // master clock accuracy
4411     hci_emit_event(event, sizeof(event), 1);
4412 }
4413 #endif
4414 #endif
4415 
4416 static void hci_emit_transport_packet_sent(void){
4417     // notify upper stack that it might be possible to send again
4418     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4419     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4420 }
4421 
4422 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4423     uint8_t event[6];
4424     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4425     event[1] = sizeof(event) - 2;
4426     event[2] = 0; // status = OK
4427     little_endian_store_16(event, 3, con_handle);
4428     event[5] = reason;
4429     hci_emit_event(event, sizeof(event), 1);
4430 }
4431 
4432 static void hci_emit_nr_connections_changed(void){
4433     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4434     uint8_t event[3];
4435     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4436     event[1] = sizeof(event) - 2;
4437     event[2] = nr_hci_connections();
4438     hci_emit_event(event, sizeof(event), 1);
4439 }
4440 
4441 static void hci_emit_hci_open_failed(void){
4442     log_info("BTSTACK_EVENT_POWERON_FAILED");
4443     uint8_t event[2];
4444     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4445     event[1] = sizeof(event) - 2;
4446     hci_emit_event(event, sizeof(event), 1);
4447 }
4448 
4449 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4450     log_info("hci_emit_dedicated_bonding_result %u ", status);
4451     uint8_t event[9];
4452     int pos = 0;
4453     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4454     event[pos++] = sizeof(event) - 2;
4455     event[pos++] = status;
4456     reverse_bd_addr(address, &event[pos]);
4457     hci_emit_event(event, sizeof(event), 1);
4458 }
4459 
4460 
4461 #ifdef ENABLE_CLASSIC
4462 
4463 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4464     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4465     uint8_t event[5];
4466     int pos = 0;
4467     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4468     event[pos++] = sizeof(event) - 2;
4469     little_endian_store_16(event, 2, con_handle);
4470     pos += 2;
4471     event[pos++] = level;
4472     hci_emit_event(event, sizeof(event), 1);
4473 }
4474 
4475 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4476     if (!connection) return LEVEL_0;
4477     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4478     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4479     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4480     // LEVEL 4 always requires 128 bit encrytion key size
4481     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4482         security_level = LEVEL_3;
4483     }
4484     return security_level;
4485 }
4486 
4487 static void hci_emit_discoverable_enabled(uint8_t enabled){
4488     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4489     uint8_t event[3];
4490     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4491     event[1] = sizeof(event) - 2;
4492     event[2] = enabled;
4493     hci_emit_event(event, sizeof(event), 1);
4494 }
4495 
4496 // query if remote side supports eSCO
4497 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4498     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4499     if (!connection) return 0;
4500     return connection->remote_supported_feature_eSCO;
4501 }
4502 
4503 // query if remote side supports SSP
4504 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4505     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4506     if (!connection) return 0;
4507     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
4508 }
4509 
4510 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4511     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4512 }
4513 
4514 // GAP API
4515 /**
4516  * @bbrief enable/disable bonding. default is enabled
4517  * @praram enabled
4518  */
4519 void gap_set_bondable_mode(int enable){
4520     hci_stack->bondable = enable ? 1 : 0;
4521 }
4522 /**
4523  * @brief Get bondable mode.
4524  * @return 1 if bondable
4525  */
4526 int gap_get_bondable_mode(void){
4527     return hci_stack->bondable;
4528 }
4529 
4530 /**
4531  * @brief map link keys to security levels
4532  */
4533 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4534     switch (link_key_type){
4535         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4536             return LEVEL_4;
4537         case COMBINATION_KEY:
4538         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4539             return LEVEL_3;
4540         default:
4541             return LEVEL_2;
4542     }
4543 }
4544 
4545 /**
4546  * @brief map link keys to secure connection yes/no
4547  */
4548 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4549     switch (link_key_type){
4550         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4551         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4552             return 1;
4553         default:
4554             return 0;
4555     }
4556 }
4557 
4558 /**
4559  * @brief map link keys to authenticated
4560  */
4561 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4562     switch (link_key_type){
4563         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4564         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4565             return 1;
4566         default:
4567             return 0;
4568     }
4569 }
4570 
4571 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4572     log_info("gap_mitm_protection_required_for_security_level %u", level);
4573     return level > LEVEL_2;
4574 }
4575 
4576 /**
4577  * @brief get current security level
4578  */
4579 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4580     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4581     if (!connection) return LEVEL_0;
4582     return gap_security_level_for_connection(connection);
4583 }
4584 
4585 /**
4586  * @brief request connection to device to
4587  * @result GAP_AUTHENTICATION_RESULT
4588  */
4589 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4590     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4591     if (!connection){
4592         hci_emit_security_level(con_handle, LEVEL_0);
4593         return;
4594     }
4595     gap_security_level_t current_level = gap_security_level(con_handle);
4596     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4597         requested_level, connection->requested_security_level, current_level);
4598 
4599     // assumption: earlier requested security higher than current level => security request is active
4600     if (current_level < connection->requested_security_level){
4601         if (connection->requested_security_level < requested_level){
4602             // increase requested level as new level is higher
4603 
4604             // TODO: handle re-authentication when done
4605 
4606             connection->requested_security_level = requested_level;
4607         }
4608         return;
4609     }
4610 
4611     // no request active, notify if security sufficient
4612     if (requested_level <= current_level){
4613         hci_emit_security_level(con_handle, current_level);
4614         return;
4615     }
4616 
4617     // start pairing to increase security level
4618     connection->requested_security_level = requested_level;
4619 
4620 #if 0
4621     // sending encryption request without a link key results in an error.
4622     // TODO: figure out how to use it properly
4623 
4624     // would enabling ecnryption suffice (>= LEVEL_2)?
4625     if (hci_stack->link_key_db){
4626         link_key_type_t link_key_type;
4627         link_key_t      link_key;
4628         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4629             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4630                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4631                 return;
4632             }
4633         }
4634     }
4635 #endif
4636 
4637     // start to authenticate connection
4638     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4639     hci_run();
4640 }
4641 
4642 /**
4643  * @brief start dedicated bonding with device. disconnect after bonding
4644  * @param device
4645  * @param request MITM protection
4646  * @result GAP_DEDICATED_BONDING_COMPLETE
4647  */
4648 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4649 
4650     // create connection state machine
4651     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4652 
4653     if (!connection){
4654         return BTSTACK_MEMORY_ALLOC_FAILED;
4655     }
4656 
4657     // delete linkn key
4658     gap_drop_link_key_for_bd_addr(device);
4659 
4660     // configure LEVEL_2/3, dedicated bonding
4661     connection->state = SEND_CREATE_CONNECTION;
4662     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4663     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4664     connection->bonding_flags = BONDING_DEDICATED;
4665 
4666     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4667 
4668     // handle: connnection failure (connection complete != ok)
4669     // handle: authentication failure
4670     // handle: disconnect on done
4671 
4672     hci_run();
4673 
4674     return 0;
4675 }
4676 #endif
4677 
4678 void gap_set_local_name(const char * local_name){
4679     hci_stack->local_name = local_name;
4680 }
4681 
4682 
4683 #ifdef ENABLE_BLE
4684 
4685 #ifdef ENABLE_LE_CENTRAL
4686 void gap_start_scan(void){
4687     hci_stack->le_scanning_enabled = 1;
4688     hci_run();
4689 }
4690 
4691 void gap_stop_scan(void){
4692     hci_stack->le_scanning_enabled = 0;
4693     hci_run();
4694 }
4695 
4696 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4697     hci_stack->le_scan_type     = scan_type;
4698     hci_stack->le_scan_interval = scan_interval;
4699     hci_stack->le_scan_window   = scan_window;
4700     hci_run();
4701 }
4702 
4703 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4704     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4705     if (!conn){
4706         log_info("gap_connect: no connection exists yet, creating context");
4707         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4708         if (!conn){
4709             // notify client that alloc failed
4710             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4711             log_info("gap_connect: failed to alloc hci_connection_t");
4712             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4713         }
4714         conn->state = SEND_CREATE_CONNECTION;
4715         log_info("gap_connect: send create connection next");
4716         hci_run();
4717         return ERROR_CODE_SUCCESS;
4718     }
4719 
4720     if (!hci_is_le_connection(conn) ||
4721         (conn->state == SEND_CREATE_CONNECTION) ||
4722         (conn->state == SENT_CREATE_CONNECTION)) {
4723         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4724         log_error("gap_connect: classic connection or connect is already being created");
4725         return GATT_CLIENT_IN_WRONG_STATE;
4726     }
4727 
4728     // check if connection was just disconnected
4729     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4730         log_info("gap_connect: send create connection (again)");
4731         conn->state = SEND_CREATE_CONNECTION;
4732         hci_run();
4733         return ERROR_CODE_SUCCESS;
4734     }
4735 
4736     log_info("gap_connect: context exists with state %u", conn->state);
4737     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4738     hci_run();
4739     return ERROR_CODE_SUCCESS;
4740 }
4741 
4742 // @assumption: only a single outgoing LE Connection exists
4743 static hci_connection_t * gap_get_outgoing_connection(void){
4744     btstack_linked_item_t *it;
4745     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4746         hci_connection_t * conn = (hci_connection_t *) it;
4747         if (!hci_is_le_connection(conn)) continue;
4748         switch (conn->state){
4749             case SEND_CREATE_CONNECTION:
4750             case SENT_CREATE_CONNECTION:
4751             case SENT_CANCEL_CONNECTION:
4752                 return conn;
4753             default:
4754                 break;
4755         };
4756     }
4757     return NULL;
4758 }
4759 
4760 uint8_t gap_connect_cancel(void){
4761     hci_connection_t * conn = gap_get_outgoing_connection();
4762     if (!conn) return 0;
4763     switch (conn->state){
4764         case SEND_CREATE_CONNECTION:
4765             // skip sending create connection and emit event instead
4766             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4767             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4768             btstack_memory_hci_connection_free( conn );
4769             break;
4770         case SENT_CREATE_CONNECTION:
4771             // request to send cancel connection
4772             conn->state = SEND_CANCEL_CONNECTION;
4773             hci_run();
4774             break;
4775         default:
4776             break;
4777     }
4778     return 0;
4779 }
4780 #endif
4781 
4782 #ifdef ENABLE_LE_CENTRAL
4783 /**
4784  * @brief Set connection parameters for outgoing connections
4785  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4786  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4787  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4788  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4789  * @param conn_latency, default: 4
4790  * @param supervision_timeout (unit: 10ms), default: 720 ms
4791  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4792  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4793  */
4794 
4795 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4796     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4797     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4798     hci_stack->le_connection_scan_interval = conn_scan_interval;
4799     hci_stack->le_connection_scan_window = conn_scan_window;
4800     hci_stack->le_connection_interval_min = conn_interval_min;
4801     hci_stack->le_connection_interval_max = conn_interval_max;
4802     hci_stack->le_connection_latency = conn_latency;
4803     hci_stack->le_supervision_timeout = supervision_timeout;
4804     hci_stack->le_minimum_ce_length = min_ce_length;
4805     hci_stack->le_maximum_ce_length = max_ce_length;
4806 }
4807 #endif
4808 
4809 /**
4810  * @brief Updates the connection parameters for a given LE connection
4811  * @param handle
4812  * @param conn_interval_min (unit: 1.25ms)
4813  * @param conn_interval_max (unit: 1.25ms)
4814  * @param conn_latency
4815  * @param supervision_timeout (unit: 10ms)
4816  * @returns 0 if ok
4817  */
4818 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4819     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4820     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4821     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4822     connection->le_conn_interval_min = conn_interval_min;
4823     connection->le_conn_interval_max = conn_interval_max;
4824     connection->le_conn_latency = conn_latency;
4825     connection->le_supervision_timeout = supervision_timeout;
4826     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4827     hci_run();
4828     return 0;
4829 }
4830 
4831 /**
4832  * @brief Request an update of the connection parameter for a given LE connection
4833  * @param handle
4834  * @param conn_interval_min (unit: 1.25ms)
4835  * @param conn_interval_max (unit: 1.25ms)
4836  * @param conn_latency
4837  * @param supervision_timeout (unit: 10ms)
4838  * @returns 0 if ok
4839  */
4840 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4841     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4842     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4843     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4844     connection->le_conn_interval_min = conn_interval_min;
4845     connection->le_conn_interval_max = conn_interval_max;
4846     connection->le_conn_latency = conn_latency;
4847     connection->le_supervision_timeout = supervision_timeout;
4848     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4849     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4850     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4851     return 0;
4852 }
4853 
4854 #ifdef ENABLE_LE_PERIPHERAL
4855 
4856 static void gap_advertisments_changed(void){
4857     // disable advertisements before updating adv, scan data, or adv params
4858     if (hci_stack->le_advertisements_active){
4859         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4860     }
4861     hci_run();
4862 }
4863 
4864 /**
4865  * @brief Set Advertisement Data
4866  * @param advertising_data_length
4867  * @param advertising_data (max 31 octets)
4868  * @note data is not copied, pointer has to stay valid
4869  */
4870 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4871     hci_stack->le_advertisements_data_len = advertising_data_length;
4872     hci_stack->le_advertisements_data = advertising_data;
4873     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4874     gap_advertisments_changed();
4875 }
4876 
4877 /**
4878  * @brief Set Scan Response Data
4879  * @param advertising_data_length
4880  * @param advertising_data (max 31 octets)
4881  * @note data is not copied, pointer has to stay valid
4882  */
4883 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4884     hci_stack->le_scan_response_data_len = scan_response_data_length;
4885     hci_stack->le_scan_response_data = scan_response_data;
4886     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4887     gap_advertisments_changed();
4888 }
4889 
4890 /**
4891  * @brief Set Advertisement Parameters
4892  * @param adv_int_min
4893  * @param adv_int_max
4894  * @param adv_type
4895  * @param direct_address_type
4896  * @param direct_address
4897  * @param channel_map
4898  * @param filter_policy
4899  *
4900  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4901  */
4902  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4903     uint8_t direct_address_typ, bd_addr_t direct_address,
4904     uint8_t channel_map, uint8_t filter_policy) {
4905 
4906     hci_stack->le_advertisements_interval_min = adv_int_min;
4907     hci_stack->le_advertisements_interval_max = adv_int_max;
4908     hci_stack->le_advertisements_type = adv_type;
4909     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4910     hci_stack->le_advertisements_channel_map = channel_map;
4911     hci_stack->le_advertisements_filter_policy = filter_policy;
4912     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
4913                  6);
4914 
4915     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4916     gap_advertisments_changed();
4917  }
4918 
4919 /**
4920  * @brief Enable/Disable Advertisements
4921  * @param enabled
4922  */
4923 void gap_advertisements_enable(int enabled){
4924     hci_stack->le_advertisements_enabled = enabled;
4925     if (enabled && !hci_stack->le_advertisements_active){
4926         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
4927     }
4928     if (!enabled && hci_stack->le_advertisements_active){
4929         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
4930     }
4931     hci_run();
4932 }
4933 
4934 #endif
4935 
4936 void hci_le_set_own_address_type(uint8_t own_address_type){
4937     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
4938     if (own_address_type == hci_stack->le_own_addr_type) return;
4939     hci_stack->le_own_addr_type = own_address_type;
4940 
4941 #ifdef ENABLE_LE_PERIPHERAL
4942     // update advertisement parameters, too
4943     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4944     gap_advertisments_changed();
4945 #endif
4946 #ifdef ENABLE_LE_CENTRAL
4947     // note: we don't update scan parameters or modify ongoing connection attempts
4948 #endif
4949 }
4950 
4951 #endif
4952 
4953 uint8_t gap_disconnect(hci_con_handle_t handle){
4954     hci_connection_t * conn = hci_connection_for_handle(handle);
4955     if (!conn){
4956         hci_emit_disconnection_complete(handle, 0);
4957         return 0;
4958     }
4959     // ignore if already disconnected
4960     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4961         return 0;
4962     }
4963     conn->state = SEND_DISCONNECT;
4964     hci_run();
4965     return 0;
4966 }
4967 
4968 int gap_read_rssi(hci_con_handle_t con_handle){
4969     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
4970     if (hci_connection == NULL) return 0;
4971     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
4972     hci_run();
4973     return 1;
4974 }
4975 
4976 /**
4977  * @brief Get connection type
4978  * @param con_handle
4979  * @result connection_type
4980  */
4981 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
4982     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4983     if (!conn) return GAP_CONNECTION_INVALID;
4984     switch (conn->address_type){
4985         case BD_ADDR_TYPE_LE_PUBLIC:
4986         case BD_ADDR_TYPE_LE_RANDOM:
4987             return GAP_CONNECTION_LE;
4988         case BD_ADDR_TYPE_SCO:
4989             return GAP_CONNECTION_SCO;
4990         case BD_ADDR_TYPE_ACL:
4991             return GAP_CONNECTION_ACL;
4992         default:
4993             return GAP_CONNECTION_INVALID;
4994     }
4995 }
4996 
4997 #ifdef ENABLE_BLE
4998 
4999 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){
5000     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5001     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5002 
5003     conn->le_phy_update_all_phys    = all_phys;
5004     conn->le_phy_update_tx_phys     = tx_phys;
5005     conn->le_phy_update_rx_phys     = rx_phys;
5006     conn->le_phy_update_phy_options = phy_options;
5007 
5008     hci_run();
5009 
5010     return 0;
5011 }
5012 
5013 #ifdef ENABLE_LE_CENTRAL
5014 /**
5015  * @brief Auto Connection Establishment - Start Connecting to device
5016  * @param address_typ
5017  * @param address
5018  * @returns 0 if ok
5019  */
5020 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5021     // check capacity
5022     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5023     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5024     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5025     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5026     entry->address_type = address_type;
5027     (void)memcpy(entry->address, address, 6);
5028     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5029     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5030     hci_run();
5031     return 0;
5032 }
5033 
5034 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5035     btstack_linked_list_iterator_t it;
5036     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5037     while (btstack_linked_list_iterator_has_next(&it)){
5038         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5039         if (entry->address_type != address_type) continue;
5040         if (memcmp(entry->address, address, 6) != 0) continue;
5041         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5042             // remove from controller if already present
5043             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5044             continue;
5045         }
5046         // direclty remove entry from whitelist
5047         btstack_linked_list_iterator_remove(&it);
5048         btstack_memory_whitelist_entry_free(entry);
5049     }
5050 }
5051 
5052 /**
5053  * @brief Auto Connection Establishment - Stop Connecting to device
5054  * @param address_typ
5055  * @param address
5056  * @returns 0 if ok
5057  */
5058 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5059     hci_remove_from_whitelist(address_type, address);
5060     hci_run();
5061     return 0;
5062 }
5063 
5064 /**
5065  * @brief Auto Connection Establishment - Stop everything
5066  * @note  Convenience function to stop all active auto connection attempts
5067  */
5068 void gap_auto_connection_stop_all(void){
5069     btstack_linked_list_iterator_t it;
5070     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5071     while (btstack_linked_list_iterator_has_next(&it)){
5072         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5073         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5074             // remove from controller if already present
5075             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5076             continue;
5077         }
5078         // directly remove entry from whitelist
5079         btstack_linked_list_iterator_remove(&it);
5080         btstack_memory_whitelist_entry_free(entry);
5081     }
5082     hci_run();
5083 }
5084 
5085 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5086     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5087     if (!conn) return 0;
5088     return conn->le_connection_interval;
5089 }
5090 #endif
5091 #endif
5092 
5093 #ifdef ENABLE_CLASSIC
5094 /**
5095  * @brief Set Extended Inquiry Response data
5096  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5097  * @note has to be done before stack starts up
5098  */
5099 void gap_set_extended_inquiry_response(const uint8_t * data){
5100     hci_stack->eir_data = data;
5101 }
5102 
5103 /**
5104  * @brief Start GAP Classic Inquiry
5105  * @param duration in 1.28s units
5106  * @return 0 if ok
5107  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5108  */
5109 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5110     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5111     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5112     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5113         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5114     }
5115     hci_stack->inquiry_state = duration_in_1280ms_units;
5116     hci_run();
5117     return 0;
5118 }
5119 
5120 /**
5121  * @brief Stop GAP Classic Inquiry
5122  * @returns 0 if ok
5123  */
5124 int gap_inquiry_stop(void){
5125     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5126         // emit inquiry complete event, before it even started
5127         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5128         hci_emit_event(event, sizeof(event), 1);
5129         return 0;
5130     }
5131     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5132     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5133     hci_run();
5134     return 0;
5135 }
5136 
5137 
5138 /**
5139  * @brief Remote Name Request
5140  * @param addr
5141  * @param page_scan_repetition_mode
5142  * @param clock_offset only used when bit 15 is set
5143  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5144  */
5145 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5146     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5147     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5148     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5149     hci_stack->remote_name_clock_offset = clock_offset;
5150     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5151     hci_run();
5152     return 0;
5153 }
5154 
5155 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5156     hci_stack->gap_pairing_state = state;
5157     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5158     hci_run();
5159     return 0;
5160 }
5161 
5162 /**
5163  * @brief Legacy Pairing Pin Code Response
5164  * @param addr
5165  * @param pin
5166  * @return 0 if ok
5167  */
5168 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5169     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5170     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5171     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5172 }
5173 
5174 /**
5175  * @brief Abort Legacy Pairing
5176  * @param addr
5177  * @param pin
5178  * @return 0 if ok
5179  */
5180 int gap_pin_code_negative(bd_addr_t addr){
5181     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5182     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5183 }
5184 
5185 /**
5186  * @brief SSP Passkey Response
5187  * @param addr
5188  * @param passkey
5189  * @return 0 if ok
5190  */
5191 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5192     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5193     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5194     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5195 }
5196 
5197 /**
5198  * @brief Abort SSP Passkey Entry/Pairing
5199  * @param addr
5200  * @param pin
5201  * @return 0 if ok
5202  */
5203 int gap_ssp_passkey_negative(bd_addr_t addr){
5204     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5205     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5206 }
5207 
5208 /**
5209  * @brief Accept SSP Numeric Comparison
5210  * @param addr
5211  * @param passkey
5212  * @return 0 if ok
5213  */
5214 int gap_ssp_confirmation_response(bd_addr_t addr){
5215     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5216     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5217 }
5218 
5219 /**
5220  * @brief Abort SSP Numeric Comparison/Pairing
5221  * @param addr
5222  * @param pin
5223  * @return 0 if ok
5224  */
5225 int gap_ssp_confirmation_negative(bd_addr_t addr){
5226     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5227     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5228 }
5229 
5230 /**
5231  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5232  * @param inquiry_mode see bluetooth_defines.h
5233  */
5234 void hci_set_inquiry_mode(inquiry_mode_t mode){
5235     hci_stack->inquiry_mode = mode;
5236 }
5237 
5238 /**
5239  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5240  */
5241 void hci_set_sco_voice_setting(uint16_t voice_setting){
5242     hci_stack->sco_voice_setting = voice_setting;
5243 }
5244 
5245 /**
5246  * @brief Get SCO Voice Setting
5247  * @return current voice setting
5248  */
5249 uint16_t hci_get_sco_voice_setting(void){
5250     return hci_stack->sco_voice_setting;
5251 }
5252 
5253 static int hci_have_usb_transport(void){
5254     if (!hci_stack->hci_transport) return 0;
5255     const char * transport_name = hci_stack->hci_transport->name;
5256     if (!transport_name) return 0;
5257     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5258 }
5259 
5260 /** @brief Get SCO packet length for current SCO Voice setting
5261  *  @note  Using SCO packets of the exact length is required for USB transfer
5262  *  @return Length of SCO packets in bytes (not audio frames)
5263  */
5264 int hci_get_sco_packet_length(void){
5265     int sco_packet_length = 0;
5266 
5267 #ifdef ENABLE_SCO_OVER_HCI
5268 
5269     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5270     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5271 
5272     if (hci_have_usb_transport()){
5273         // see Core Spec for H2 USB Transfer.
5274         // 3 byte SCO header + 24 bytes per connection
5275         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5276         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5277     } else {
5278         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5279         sco_packet_length = 3 + 60 * multiplier;
5280         // assert that it still fits inside an SCO buffer
5281         if (sco_packet_length > hci_stack->sco_data_packet_length){
5282             sco_packet_length = 3 + 60;
5283         }
5284     }
5285 #endif
5286     return sco_packet_length;
5287 }
5288 
5289 /**
5290 * @brief Sets the master/slave policy
5291 * @param policy (0: attempt to become master, 1: let connecting device decide)
5292 */
5293 void hci_set_master_slave_policy(uint8_t policy){
5294     hci_stack->master_slave_policy = policy;
5295 }
5296 
5297 #endif
5298 
5299 HCI_STATE hci_get_state(void){
5300     return hci_stack->state;
5301 }
5302 
5303 #ifdef ENABLE_CLASSIC
5304 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5305     hci_stack->gap_classic_accept_callback = accept_callback;
5306 }
5307 #endif
5308 
5309 /**
5310  * @brief Set callback for Bluetooth Hardware Error
5311  */
5312 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5313     hci_stack->hardware_error_callback = fn;
5314 }
5315 
5316 void hci_disconnect_all(void){
5317     btstack_linked_list_iterator_t it;
5318     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5319     while (btstack_linked_list_iterator_has_next(&it)){
5320         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5321         if (con->state == SENT_DISCONNECT) continue;
5322         con->state = SEND_DISCONNECT;
5323     }
5324     hci_run();
5325 }
5326 
5327 uint16_t hci_get_manufacturer(void){
5328     return hci_stack->manufacturer;
5329 }
5330 
5331 #ifdef ENABLE_BLE
5332 
5333 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5334     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5335     if (!hci_con) return NULL;
5336     return &hci_con->sm_connection;
5337 }
5338 
5339 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5340 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5341 
5342 int gap_encryption_key_size(hci_con_handle_t con_handle){
5343     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5344     if (hci_connection == NULL) return 0;
5345     if (hci_is_le_connection(hci_connection)){
5346         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5347         if (sm_conn->sm_connection_encrypted) {
5348             return sm_conn->sm_actual_encryption_key_size;
5349         }
5350     }
5351 #ifdef ENABLE_CLASSIC
5352     else {
5353         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5354             return hci_connection->encryption_key_size;
5355         }
5356     }
5357 #endif
5358     return 0;
5359 }
5360 
5361 int gap_authenticated(hci_con_handle_t con_handle){
5362     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5363     if (hci_connection == NULL) return 0;
5364 
5365     switch (hci_connection->address_type){
5366         case BD_ADDR_TYPE_LE_PUBLIC:
5367         case BD_ADDR_TYPE_LE_RANDOM:
5368             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5369             return hci_connection->sm_connection.sm_connection_authenticated;
5370 #ifdef ENABLE_CLASSIC
5371         case BD_ADDR_TYPE_SCO:
5372         case BD_ADDR_TYPE_ACL:
5373             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5374 #endif
5375         default:
5376             return 0;
5377     }
5378 }
5379 
5380 int gap_secure_connection(hci_con_handle_t con_handle){
5381     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5382     if (hci_connection == NULL) return 0;
5383 
5384     switch (hci_connection->address_type){
5385         case BD_ADDR_TYPE_LE_PUBLIC:
5386         case BD_ADDR_TYPE_LE_RANDOM:
5387             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5388             return hci_connection->sm_connection.sm_connection_sc;
5389 #ifdef ENABLE_CLASSIC
5390         case BD_ADDR_TYPE_SCO:
5391         case BD_ADDR_TYPE_ACL:
5392             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5393 #endif
5394         default:
5395             return 0;
5396     }
5397 }
5398 
5399 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5400     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5401     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5402     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5403     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5404     return sm_conn->sm_connection_authorization_state;
5405 }
5406 #endif
5407 
5408 #ifdef ENABLE_CLASSIC
5409 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){
5410     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5411     if (!conn) return GAP_CONNECTION_INVALID;
5412     conn->sniff_min_interval = sniff_min_interval;
5413     conn->sniff_max_interval = sniff_max_interval;
5414     conn->sniff_attempt = sniff_attempt;
5415     conn->sniff_timeout = sniff_timeout;
5416     hci_run();
5417     return 0;
5418 }
5419 
5420 /**
5421  * @brief Exit Sniff mode
5422  * @param con_handle
5423  @ @return 0 if ok
5424  */
5425 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5426     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5427     if (!conn) return GAP_CONNECTION_INVALID;
5428     conn->sniff_min_interval = 0xffff;
5429     hci_run();
5430     return 0;
5431 }
5432 #endif
5433 
5434 void hci_halting_defer(void){
5435     if (hci_stack->state != HCI_STATE_HALTING) return;
5436     switch (hci_stack->substate){
5437         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5438         case HCI_HALTING_CLOSE:
5439             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5440             break;
5441         default:
5442             break;
5443     }
5444 }
5445 
5446 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5447 void hci_setup_test_connections_fuzz(void){
5448     hci_connection_t * conn;
5449 
5450     // default address: 66:55:44:33:00:01
5451     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5452 
5453     // setup Controller info
5454     hci_stack->num_cmd_packets = 255;
5455     hci_stack->acl_packets_total_num = 255;
5456 
5457     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5458     addr[5] = 0x01;
5459     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5460     conn->con_handle = addr[5];
5461     conn->role  = HCI_ROLE_SLAVE;
5462     conn->state = RECEIVED_CONNECTION_REQUEST;
5463     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5464 
5465     // setup incoming Classic SCO connection with con handle 0x0002
5466     addr[5] = 0x02;
5467     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5468     conn->con_handle = addr[5];
5469     conn->role  = HCI_ROLE_SLAVE;
5470     conn->state = RECEIVED_CONNECTION_REQUEST;
5471     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5472 
5473     // setup ready Classic ACL connection with con handle 0x0003
5474     addr[5] = 0x03;
5475     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5476     conn->con_handle = addr[5];
5477     conn->role  = HCI_ROLE_SLAVE;
5478     conn->state = OPEN;
5479     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5480 
5481     // setup ready Classic SCO connection with con handle 0x0004
5482     addr[5] = 0x04;
5483     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5484     conn->con_handle = addr[5];
5485     conn->role  = HCI_ROLE_SLAVE;
5486     conn->state = OPEN;
5487     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5488 
5489     // setup ready LE ACL connection with con handle 0x005 and public address
5490     addr[5] = 0x05;
5491     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5492     conn->con_handle = addr[5];
5493     conn->role  = HCI_ROLE_SLAVE;
5494     conn->state = OPEN;
5495     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5496 }
5497 
5498 void hci_free_connections_fuzz(void){
5499     btstack_linked_list_iterator_t it;
5500     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5501     while (btstack_linked_list_iterator_has_next(&it)){
5502         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5503         btstack_linked_list_iterator_remove(&it);
5504         btstack_memory_hci_connection_free(con);
5505     }
5506 }
5507 void hci_simulate_working_fuzz(void){
5508     hci_init_done();
5509     hci_stack->num_cmd_packets = 255;
5510 }
5511 #endif
5512