xref: /btstack/src/hci.c (revision f5054c0028135915921b5f31909b986101cbedd2)
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 /*
39  *  hci.c
40  *
41  *  Created by Matthias Ringwald on 4/29/09.
42  *
43  */
44 
45 #include "btstack-config.h"
46 
47 #include "hci.h"
48 #include "gap.h"
49 
50 #ifdef HAVE_BLE
51 #include "gap.h"
52 #endif
53 
54 #include <stdarg.h>
55 #include <string.h>
56 #include <stdio.h>
57 #include <inttypes.h>
58 
59 #ifndef EMBEDDED
60 #ifdef _WIN32
61 #include "Winsock2.h"
62 #else
63 #include <unistd.h> // gethostbyname
64 #endif
65 #include "version.h"
66 #endif
67 
68 #include "btstack_memory.h"
69 #include "debug.h"
70 #include "hci_dump.h"
71 
72 #include "linked_list.h"
73 #include "hci_cmds.h"
74 
75 #define HCI_CONNECTION_TIMEOUT_MS 10000
76 
77 #ifdef USE_BLUETOOL
78 #include "../port/ios/src/bt_control_iphone.h"
79 #endif
80 
81 static void hci_update_scan_enable(void);
82 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
83 static void hci_connection_timeout_handler(timer_source_t *timer);
84 static void hci_connection_timestamp(hci_connection_t *connection);
85 static int  hci_power_control_on(void);
86 static void hci_power_control_off(void);
87 static void hci_state_reset(void);
88 
89 #ifdef HAVE_BLE
90 // called from test/ble_client/advertising_data_parser.c
91 void le_handle_advertisement_report(uint8_t *packet, int size);
92 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
93 #endif
94 
95 // the STACK is here
96 #ifndef HAVE_MALLOC
97 static hci_stack_t   hci_stack_static;
98 #endif
99 static hci_stack_t * hci_stack = NULL;
100 
101 // test helper
102 static uint8_t disable_l2cap_timeouts = 0;
103 
104 /**
105  * create connection for given address
106  *
107  * @return connection OR NULL, if no memory left
108  */
109 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
110     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
111     hci_connection_t * conn = btstack_memory_hci_connection_get();
112     if (!conn) return NULL;
113     memset(conn, 0, sizeof(hci_connection_t));
114     BD_ADDR_COPY(conn->address, addr);
115     conn->address_type = addr_type;
116     conn->con_handle = 0xffff;
117     conn->authentication_flags = AUTH_FLAGS_NONE;
118     conn->bonding_flags = 0;
119     conn->requested_security_level = LEVEL_0;
120     linked_item_set_user(&conn->timeout.item, conn);
121     conn->timeout.process = hci_connection_timeout_handler;
122     hci_connection_timestamp(conn);
123     conn->acl_recombination_length = 0;
124     conn->acl_recombination_pos = 0;
125     conn->num_acl_packets_sent = 0;
126     conn->num_sco_packets_sent = 0;
127     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
128     linked_list_add(&hci_stack->connections, (linked_item_t *) conn);
129     return conn;
130 }
131 
132 
133 /**
134  * get le connection parameter range
135 *
136  * @return le connection parameter range struct
137  */
138 void gap_le_get_connection_parameter_range(le_connection_parameter_range_t range){
139     range = hci_stack->le_connection_parameter_range;
140 }
141 
142 /**
143  * set le connection parameter range
144  *
145  */
146 
147 void gap_le_set_connection_parameter_range(le_connection_parameter_range_t range){
148     hci_stack->le_connection_parameter_range = range;
149 }
150 
151 /**
152  * get hci connections iterator
153  *
154  * @return hci connections iterator
155  */
156 
157 void hci_connections_get_iterator(linked_list_iterator_t *it){
158     linked_list_iterator_init(it, &hci_stack->connections);
159 }
160 
161 /**
162  * get connection for a given handle
163  *
164  * @return connection OR NULL, if not found
165  */
166 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
167     linked_list_iterator_t it;
168     linked_list_iterator_init(&it, &hci_stack->connections);
169     while (linked_list_iterator_has_next(&it)){
170         hci_connection_t * item = (hci_connection_t *) linked_list_iterator_next(&it);
171         if ( item->con_handle == con_handle ) {
172             return item;
173         }
174     }
175     return NULL;
176 }
177 
178 /**
179  * get connection for given address
180  *
181  * @return connection OR NULL, if not found
182  */
183 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
184     linked_list_iterator_t it;
185     linked_list_iterator_init(&it, &hci_stack->connections);
186     while (linked_list_iterator_has_next(&it)){
187         hci_connection_t * connection = (hci_connection_t *) linked_list_iterator_next(&it);
188         if (connection->address_type != addr_type)  continue;
189         if (memcmp(addr, connection->address, 6) != 0) continue;
190         return connection;
191     }
192     return NULL;
193 }
194 
195 static void hci_connection_timeout_handler(timer_source_t *timer){
196     hci_connection_t * connection = (hci_connection_t *) linked_item_get_user(&timer->item);
197 #ifdef HAVE_TIME
198     struct timeval tv;
199     gettimeofday(&tv, NULL);
200     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
201         // connections might be timed out
202         hci_emit_l2cap_check_timeout(connection);
203     }
204 #endif
205 #ifdef HAVE_TICK
206     if (embedded_get_ticks() > connection->timestamp + embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
207         // connections might be timed out
208         hci_emit_l2cap_check_timeout(connection);
209     }
210 #endif
211     run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
212     run_loop_add_timer(timer);
213 }
214 
215 static void hci_connection_timestamp(hci_connection_t *connection){
216 #ifdef HAVE_TIME
217     gettimeofday(&connection->timestamp, NULL);
218 #endif
219 #ifdef HAVE_TICK
220     connection->timestamp = embedded_get_ticks();
221 #endif
222 }
223 
224 
225 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
226     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
227 }
228 
229 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
230     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
231 }
232 
233 
234 /**
235  * add authentication flags and reset timer
236  * @note: assumes classic connection
237  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
238  */
239 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
240     bd_addr_t addr;
241     bt_flip_addr(addr, bd_addr);
242     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
243     if (conn) {
244         connectionSetAuthenticationFlags(conn, flags);
245         hci_connection_timestamp(conn);
246     }
247 }
248 
249 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
250     hci_connection_t * conn = hci_connection_for_handle(handle);
251     if (!conn) return 0;
252     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
253     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
254     return 0;
255 }
256 
257 void hci_drop_link_key_for_bd_addr(bd_addr_t addr){
258     if (hci_stack->remote_device_db) {
259         hci_stack->remote_device_db->delete_link_key(addr);
260     }
261 }
262 
263 int hci_is_le_connection(hci_connection_t * connection){
264     return  connection->address_type == BD_ADDR_TYPE_LE_PUBLIC ||
265     connection->address_type == BD_ADDR_TYPE_LE_RANDOM;
266 }
267 
268 
269 /**
270  * count connections
271  */
272 static int nr_hci_connections(void){
273     int count = 0;
274     linked_item_t *it;
275     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
276     return count;
277 }
278 
279 /**
280  * Dummy handler called by HCI
281  */
282 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
283 }
284 
285 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
286     hci_connection_t * connection = hci_connection_for_handle(handle);
287     if (!connection) {
288         log_error("hci_number_outgoing_packets: connection for handle %u does not exist!", handle);
289         return 0;
290     }
291     return connection->num_acl_packets_sent;
292 }
293 
294 uint8_t hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
295 
296     int num_packets_sent_classic = 0;
297     int num_packets_sent_le = 0;
298 
299     bd_addr_type_t address_type = BD_ADDR_TYPE_UNKNOWN;
300 
301     linked_item_t *it;
302     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
303         hci_connection_t * connection = (hci_connection_t *) it;
304         if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
305             num_packets_sent_classic += connection->num_acl_packets_sent;
306         } else {
307             num_packets_sent_le += connection->num_acl_packets_sent;
308         }
309         // ignore connections that are not open, e.g., in state RECEIVED_DISCONNECTION_COMPLETE
310         if (connection->con_handle == con_handle && connection->state == OPEN){
311             address_type = connection->address_type;
312         }
313     }
314 
315     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
316     int free_slots_le = 0;
317 
318     if (free_slots_classic < 0){
319         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);
320         return 0;
321     }
322 
323     if (hci_stack->le_acl_packets_total_num){
324         // if we have LE slots, they are used
325         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
326         if (free_slots_le < 0){
327             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);
328             return 0;
329         }
330     } else {
331         // otherwise, classic slots are used for LE, too
332         free_slots_classic -= num_packets_sent_le;
333         if (free_slots_classic < 0){
334             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);
335             return 0;
336         }
337     }
338 
339     switch (address_type){
340         case BD_ADDR_TYPE_UNKNOWN:
341             log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
342             return 0;
343 
344         case BD_ADDR_TYPE_CLASSIC:
345             return free_slots_classic;
346 
347         default:
348            if (hci_stack->le_acl_packets_total_num){
349                return free_slots_le;
350            }
351            return free_slots_classic;
352     }
353 }
354 
355 static int hci_number_free_sco_slots_for_handle(hci_con_handle_t handle){
356     int num_sco_packets_sent = 0;
357     linked_item_t *it;
358     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
359         hci_connection_t * connection = (hci_connection_t *) it;
360         num_sco_packets_sent += connection->num_sco_packets_sent;
361     }
362     if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
363         log_info("hci_number_free_sco_slots_for_handle: outgoing packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
364         return 0;
365     }
366     return hci_stack->sco_packets_total_num - num_sco_packets_sent;
367 }
368 
369 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
370 int hci_can_send_command_packet_now(void){
371     if (hci_stack->hci_packet_buffer_reserved) return 0;
372 
373     // check for async hci transport implementations
374     if (hci_stack->hci_transport->can_send_packet_now){
375         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
376             return 0;
377         }
378     }
379 
380     return hci_stack->num_cmd_packets > 0;
381 }
382 
383 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
384     // check for async hci transport implementations
385     if (hci_stack->hci_transport->can_send_packet_now){
386         if (!hci_stack->hci_transport->can_send_packet_now(HCI_ACL_DATA_PACKET)){
387             return 0;
388         }
389     }
390     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
391 }
392 
393 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
394     if (hci_stack->hci_packet_buffer_reserved) return 0;
395     return hci_can_send_prepared_acl_packet_now(con_handle);
396 }
397 
398 int hci_can_send_prepared_sco_packet_now(hci_con_handle_t con_handle){
399     if (hci_stack->hci_transport->can_send_packet_now){
400         if (!hci_stack->hci_transport->can_send_packet_now(HCI_SCO_DATA_PACKET)){
401             return 0;
402         }
403     }
404     if (!hci_stack->synchronous_flow_control_enabled) return 1;
405     return hci_number_free_sco_slots_for_handle(con_handle) > 0;
406 }
407 
408 int hci_can_send_sco_packet_now(hci_con_handle_t con_handle){
409     if (hci_stack->hci_packet_buffer_reserved) return 0;
410     return hci_can_send_prepared_sco_packet_now(con_handle);
411 }
412 
413 // used for internal checks in l2cap[-le].c
414 int hci_is_packet_buffer_reserved(void){
415     return hci_stack->hci_packet_buffer_reserved;
416 }
417 
418 // reserves outgoing packet buffer. @returns 1 if successful
419 int hci_reserve_packet_buffer(void){
420     if (hci_stack->hci_packet_buffer_reserved) {
421         log_error("hci_reserve_packet_buffer called but buffer already reserved");
422         return 0;
423     }
424     hci_stack->hci_packet_buffer_reserved = 1;
425     return 1;
426 }
427 
428 void hci_release_packet_buffer(void){
429     hci_stack->hci_packet_buffer_reserved = 0;
430 }
431 
432 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
433 static int hci_transport_synchronous(void){
434     return hci_stack->hci_transport->can_send_packet_now == NULL;
435 }
436 
437 uint16_t hci_max_acl_le_data_packet_length(void){
438     return hci_stack->le_data_packets_length > 0 ? hci_stack->le_data_packets_length : hci_stack->acl_data_packet_length;
439 }
440 
441 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
442 
443     // 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);
444 
445     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
446     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
447     if (hci_is_le_connection(connection) && hci_stack->le_data_packets_length > 0){
448         max_acl_data_packet_length = hci_stack->le_data_packets_length;
449     }
450 
451     // testing: reduce buffer to minimum
452     // max_acl_data_packet_length = 52;
453 
454     int err;
455     // multiple packets could be send on a synchronous HCI transport
456     while (1){
457 
458         // get current data
459         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
460         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
461         int more_fragments = 0;
462 
463         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
464         if (current_acl_data_packet_length > max_acl_data_packet_length){
465             more_fragments = 1;
466             current_acl_data_packet_length = max_acl_data_packet_length;
467         }
468 
469         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
470         if (acl_header_pos > 0){
471             uint16_t handle_and_flags = READ_BT_16(hci_stack->hci_packet_buffer, 0);
472             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
473             bt_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
474         }
475 
476         // update header len
477         bt_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
478 
479         // count packet
480         connection->num_acl_packets_sent++;
481 
482         // send packet
483         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
484         const int size = current_acl_data_packet_length + 4;
485         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
486         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
487 
488         // done yet?
489         if (!more_fragments) break;
490 
491         // update start of next fragment to send
492         hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
493 
494         // can send more?
495         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
496     }
497 
498     // done
499     hci_stack->acl_fragmentation_pos = 0;
500     hci_stack->acl_fragmentation_total_size = 0;
501 
502     // release buffer now for synchronous transport
503     if (hci_transport_synchronous()){
504         hci_release_packet_buffer();
505         // notify upper stack that iit might be possible to send again
506         uint8_t event[] = { DAEMON_EVENT_HCI_PACKET_SENT, 0};
507         hci_stack->packet_handler(HCI_EVENT_PACKET, &event[0], sizeof(event));
508     }
509 
510     return err;
511 }
512 
513 // pre: caller has reserved the packet buffer
514 int hci_send_acl_packet_buffer(int size){
515 
516     // log_info("hci_send_acl_packet_buffer size %u", size);
517 
518     if (!hci_stack->hci_packet_buffer_reserved) {
519         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
520         return 0;
521     }
522 
523     uint8_t * packet = hci_stack->hci_packet_buffer;
524     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
525 
526     // check for free places on Bluetooth module
527     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
528         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
529         hci_release_packet_buffer();
530         return BTSTACK_ACL_BUFFERS_FULL;
531     }
532 
533     hci_connection_t *connection = hci_connection_for_handle( con_handle);
534     if (!connection) {
535         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
536         hci_release_packet_buffer();
537         return 0;
538     }
539     hci_connection_timestamp(connection);
540 
541     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
542 
543     // setup data
544     hci_stack->acl_fragmentation_total_size = size;
545     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
546 
547     return hci_send_acl_packet_fragments(connection);
548 }
549 
550 // pre: caller has reserved the packet buffer
551 int hci_send_sco_packet_buffer(int size){
552 
553     // log_info("hci_send_acl_packet_buffer size %u", size);
554 
555     if (!hci_stack->hci_packet_buffer_reserved) {
556         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
557         return 0;
558     }
559 
560     uint8_t * packet = hci_stack->hci_packet_buffer;
561 
562     // skip checks in loopback mode
563     if (!hci_stack->loopback_mode){
564         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
565 
566         // check for free places on Bluetooth module
567         if (!hci_can_send_prepared_sco_packet_now(con_handle)) {
568             log_error("hci_send_sco_packet_buffer called but no free ACL buffers on controller");
569             hci_release_packet_buffer();
570             return BTSTACK_ACL_BUFFERS_FULL;
571         }
572 
573         // track send packet in connection struct
574         hci_connection_t *connection = hci_connection_for_handle( con_handle);
575         if (!connection) {
576             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
577             hci_release_packet_buffer();
578             return 0;
579         }
580         connection->num_sco_packets_sent++;
581     }
582 
583     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
584     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
585 
586     if (hci_transport_synchronous()){
587         hci_release_packet_buffer();
588         // notify upper stack that iit might be possible to send again
589         uint8_t event[] = { DAEMON_EVENT_HCI_PACKET_SENT, 0};
590         hci_stack->packet_handler(HCI_EVENT_PACKET, &event[0], sizeof(event));
591     }
592 
593     return err;
594 }
595 
596 static void acl_handler(uint8_t *packet, int size){
597 
598     // log_info("acl_handler: size %u", size);
599 
600     // get info
601     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
602     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
603     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
604     uint16_t acl_length         = READ_ACL_LENGTH(packet);
605 
606     // ignore non-registered handle
607     if (!conn){
608         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
609         return;
610     }
611 
612     // assert packet is complete
613     if (acl_length + 4 != size){
614         log_error("hci.c: acl_handler called with ACL packet of wrong size %u, expected %u => dropping packet", size, acl_length + 4);
615         return;
616     }
617 
618     // update idle timestamp
619     hci_connection_timestamp(conn);
620 
621     // handle different packet types
622     switch (acl_flags & 0x03) {
623 
624         case 0x01: // continuation fragment
625 
626             // sanity checks
627             if (conn->acl_recombination_pos == 0) {
628                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
629                 return;
630             }
631             if (conn->acl_recombination_pos + acl_length > 4 + HCI_ACL_BUFFER_SIZE){
632                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
633                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
634                 conn->acl_recombination_pos = 0;
635                 return;
636             }
637 
638             // append fragment payload (header already stored)
639             memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos], &packet[4], acl_length );
640             conn->acl_recombination_pos += acl_length;
641 
642             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
643             //        conn->acl_recombination_pos, conn->acl_recombination_length);
644 
645             // forward complete L2CAP packet if complete.
646             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
647 
648                 hci_stack->packet_handler(HCI_ACL_DATA_PACKET, &conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
649                 // reset recombination buffer
650                 conn->acl_recombination_length = 0;
651                 conn->acl_recombination_pos = 0;
652             }
653             break;
654 
655         case 0x02: { // first fragment
656 
657             // sanity check
658             if (conn->acl_recombination_pos) {
659                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
660                 conn->acl_recombination_pos = 0;
661             }
662 
663             // peek into L2CAP packet!
664             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
665 
666             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
667 
668             // compare fragment size to L2CAP packet size
669             if (acl_length >= l2cap_length + 4){
670 
671                 // forward fragment as L2CAP packet
672                 hci_stack->packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
673 
674             } else {
675 
676                 if (acl_length > HCI_ACL_BUFFER_SIZE){
677                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
678                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
679                     return;
680                 }
681 
682                 // store first fragment and tweak acl length for complete package
683                 memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], packet, acl_length + 4);
684                 conn->acl_recombination_pos    = acl_length + 4;
685                 conn->acl_recombination_length = l2cap_length;
686                 bt_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
687             }
688             break;
689 
690         }
691         default:
692             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
693             return;
694     }
695 
696     // execute main loop
697     hci_run();
698 }
699 
700 static void hci_shutdown_connection(hci_connection_t *conn){
701     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
702 
703     run_loop_remove_timer(&conn->timeout);
704 
705     linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
706     btstack_memory_hci_connection_free( conn );
707 
708     // now it's gone
709     hci_emit_nr_connections_changed();
710 }
711 
712 static const uint16_t packet_type_sizes[] = {
713     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
714     HCI_ACL_DH1_SIZE, 0, 0, 0,
715     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
716     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
717 };
718 static const uint8_t  packet_type_feature_requirement_bit[] = {
719      0, // 3 slot packets
720      1, // 5 slot packets
721     25, // EDR 2 mpbs
722     26, // EDR 3 mbps
723     39, // 3 slot EDR packts
724     40, // 5 slot EDR packet
725 };
726 static const uint16_t packet_type_feature_packet_mask[] = {
727     0x0f00, // 3 slot packets
728     0xf000, // 5 slot packets
729     0x1102, // EDR 2 mpbs
730     0x2204, // EDR 3 mbps
731     0x0300, // 3 slot EDR packts
732     0x3000, // 5 slot EDR packet
733 };
734 
735 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
736     // enable packet types based on size
737     uint16_t packet_types = 0;
738     unsigned int i;
739     for (i=0;i<16;i++){
740         if (packet_type_sizes[i] == 0) continue;
741         if (packet_type_sizes[i] <= buffer_size){
742             packet_types |= 1 << i;
743         }
744     }
745     // disable packet types due to missing local supported features
746     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
747         int bit_idx = packet_type_feature_requirement_bit[i];
748         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
749         if (feature_set) continue;
750         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
751         packet_types &= ~packet_type_feature_packet_mask[i];
752     }
753     // flip bits for "may not be used"
754     packet_types ^= 0x3306;
755     return packet_types;
756 }
757 
758 uint16_t hci_usable_acl_packet_types(void){
759     return hci_stack->packet_types;
760 }
761 
762 uint8_t* hci_get_outgoing_packet_buffer(void){
763     // hci packet buffer is >= acl data packet length
764     return hci_stack->hci_packet_buffer;
765 }
766 
767 uint16_t hci_max_acl_data_packet_length(void){
768     return hci_stack->acl_data_packet_length;
769 }
770 
771 int hci_non_flushable_packet_boundary_flag_supported(void){
772     // No. 54, byte 6, bit 6
773     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
774 }
775 
776 static int hci_ssp_supported(void){
777     // No. 51, byte 6, bit 3
778     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
779 }
780 
781 static int hci_classic_supported(void){
782     // No. 37, byte 4, bit 5, = No BR/EDR Support
783     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
784 }
785 
786 static int hci_le_supported(void){
787 #ifdef HAVE_BLE
788     // No. 37, byte 4, bit 6 = LE Supported (Controller)
789     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
790 #else
791     return 0;
792 #endif
793 }
794 
795 // get addr type and address used in advertisement packets
796 void hci_le_advertisement_address(uint8_t * addr_type, bd_addr_t  addr){
797     *addr_type = hci_stack->adv_addr_type;
798     if (hci_stack->adv_addr_type){
799         memcpy(addr, hci_stack->adv_address, 6);
800     } else {
801         memcpy(addr, hci_stack->local_bd_addr, 6);
802     }
803 }
804 
805 #ifdef HAVE_BLE
806 void le_handle_advertisement_report(uint8_t *packet, int size){
807     int offset = 3;
808     int num_reports = packet[offset];
809     offset += 1;
810 
811     int i;
812     log_info("HCI: handle adv report with num reports: %d", num_reports);
813     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
814     for (i=0; i<num_reports;i++){
815         uint8_t data_length = packet[offset + 8];
816         uint8_t event_size = 10 + data_length;
817         int pos = 0;
818         event[pos++] = GAP_LE_ADVERTISING_REPORT;
819         event[pos++] = event_size;
820         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
821         offset += 8;
822         pos += 8;
823         event[pos++] = packet[offset + 1 + data_length]; // rssi
824         event[pos++] = packet[offset++]; //data_length;
825         memcpy(&event[pos], &packet[offset], data_length);
826         pos += data_length;
827         offset += data_length + 1; // rssi
828         hci_dump_packet( HCI_EVENT_PACKET, 0, event, pos);
829         hci_stack->packet_handler(HCI_EVENT_PACKET, event, pos);
830     }
831 }
832 #endif
833 
834 static void hci_initialization_timeout_handler(timer_source_t * ds){
835     switch (hci_stack->substate){
836         case HCI_INIT_W4_SEND_RESET:
837             log_info("Resend HCI Reset");
838             hci_stack->substate = HCI_INIT_SEND_RESET;
839             hci_stack->num_cmd_packets = 1;
840             hci_run();
841             break;
842         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
843             log_info("Resend HCI Reset - CSR Warm Boot");
844             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
845             hci_stack->num_cmd_packets = 1;
846             hci_run();
847             break;
848         case HCI_INIT_W4_SEND_BAUD_CHANGE:
849             log_info("Local baud rate change to %"PRIu32, ((hci_uart_config_t *)hci_stack->config)->baudrate_main);
850             hci_stack->hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack->config)->baudrate_main);
851             break;
852         default:
853             break;
854     }
855 }
856 
857 static void hci_initializing_next_state(void){
858     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
859 }
860 
861 // assumption: hci_can_send_command_packet_now() == true
862 static void hci_initializing_run(void){
863     log_info("hci_initializing_run: substate %u", hci_stack->substate);
864     switch (hci_stack->substate){
865         case HCI_INIT_SEND_RESET:
866             hci_state_reset();
867 
868 #ifndef USE_BLUETOOL
869             // prepare reset if command complete not received in 100ms
870             run_loop_set_timer(&hci_stack->timeout, 100);
871             run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
872             run_loop_add_timer(&hci_stack->timeout);
873 #endif
874             // send command
875             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
876             hci_send_cmd(&hci_reset);
877             break;
878         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
879             hci_send_cmd(&hci_read_local_version_information);
880             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
881             break;
882         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
883             hci_state_reset();
884             // prepare reset if command complete not received in 100ms
885             run_loop_set_timer(&hci_stack->timeout, 100);
886             run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
887             run_loop_add_timer(&hci_stack->timeout);
888             // send command
889             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
890             hci_send_cmd(&hci_reset);
891             break;
892         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
893             hci_state_reset();
894             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
895             hci_send_cmd(&hci_reset);
896             break;
897         case HCI_INIT_SET_BD_ADDR:
898             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
899             hci_stack->control->set_bd_addr_cmd(hci_stack->config, hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
900             hci_stack->last_cmd_opcode = READ_BT_16(hci_stack->hci_packet_buffer, 0);
901             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
902             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
903             break;
904         case HCI_INIT_SEND_BAUD_CHANGE:
905             hci_stack->control->baudrate_cmd(hci_stack->config, ((hci_uart_config_t *)hci_stack->config)->baudrate_main, hci_stack->hci_packet_buffer);
906             hci_stack->last_cmd_opcode = READ_BT_16(hci_stack->hci_packet_buffer, 0);
907             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
908             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
909             // STLC25000D: baudrate change happens within 0.5 s after command was send,
910             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
911             if (hci_stack->manufacturer == 0x0030){
912                 run_loop_set_timer(&hci_stack->timeout, 100);
913                 run_loop_add_timer(&hci_stack->timeout);
914             }
915             break;
916         case HCI_INIT_CUSTOM_INIT:
917             log_info("Custom init");
918             // Custom initialization
919             if (hci_stack->control && hci_stack->control->next_cmd){
920                 int valid_cmd = (*hci_stack->control->next_cmd)(hci_stack->config, hci_stack->hci_packet_buffer);
921                 if (valid_cmd){
922                     int size = 3 + hci_stack->hci_packet_buffer[2];
923                     hci_stack->last_cmd_opcode = READ_BT_16(hci_stack->hci_packet_buffer, 0);
924                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
925                     switch (valid_cmd) {
926                         case 1:
927                         default:
928                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
929                             break;
930                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
931                             log_info("CSR Warm Boot");
932                             run_loop_set_timer(&hci_stack->timeout, 100);
933                             run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
934                             run_loop_add_timer(&hci_stack->timeout);
935                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
936                             break;
937                     }
938                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
939                     break;
940                 }
941                log_info("hci_run: init script done");
942             }
943             // otherwise continue
944             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
945             hci_send_cmd(&hci_read_bd_addr);
946             break;
947         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
948             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
949             hci_send_cmd(&hci_read_local_supported_commands);
950             break;
951         case HCI_INIT_READ_BUFFER_SIZE:
952             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
953             hci_send_cmd(&hci_read_buffer_size);
954             break;
955         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATUES:
956             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATUES;
957             hci_send_cmd(&hci_read_local_supported_features);
958             break;
959         case HCI_INIT_SET_EVENT_MASK:
960             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
961             if (hci_le_supported()){
962                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
963             } else {
964                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
965                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
966             }
967             break;
968         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
969             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
970             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
971             break;
972         case HCI_INIT_WRITE_PAGE_TIMEOUT:
973             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
974             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
975             break;
976         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
977             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
978             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
979             break;
980         case HCI_INIT_WRITE_LOCAL_NAME:
981             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
982             if (hci_stack->local_name){
983                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
984             } else {
985                 char hostname[30];
986 #ifdef EMBEDDED
987                 // BTstack-11:22:33:44:55:66
988                 strcpy(hostname, "BTstack ");
989                 strcat(hostname, bd_addr_to_str(hci_stack->local_bd_addr));
990                 log_info("---> Name %s", hostname);
991 #else
992                 // hostname for POSIX systems
993                 gethostname(hostname, 30);
994                 hostname[29] = '\0';
995 #endif
996                 hci_send_cmd(&hci_write_local_name, hostname);
997             }
998             break;
999         case HCI_INIT_WRITE_SCAN_ENABLE:
1000             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1001             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1002             break;
1003 #ifdef HAVE_BLE
1004         // LE INIT
1005         case HCI_INIT_LE_READ_BUFFER_SIZE:
1006             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1007             hci_send_cmd(&hci_le_read_buffer_size);
1008             break;
1009         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1010             // LE Supported Host = 1, Simultaneous Host = 0
1011             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1012             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1013             break;
1014         case HCI_INIT_READ_WHITE_LIST_SIZE:
1015             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1016             hci_send_cmd(&hci_le_read_white_list_size);
1017             break;
1018         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1019             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, public address, accept all advs
1020             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1021             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, 0, 0);
1022             break;
1023 #endif
1024         // DONE
1025         case HCI_INIT_DONE:
1026             // done.
1027             hci_stack->state = HCI_STATE_WORKING;
1028             hci_emit_state();
1029             return;
1030         default:
1031             return;
1032     }
1033 }
1034 
1035 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1036     uint8_t command_completed = 0;
1037 
1038     if (packet[0] == HCI_EVENT_COMMAND_COMPLETE){
1039         uint16_t opcode = READ_BT_16(packet,3);
1040         if (opcode == hci_stack->last_cmd_opcode){
1041             command_completed = 1;
1042             log_info("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1043         } else {
1044             log_info("Command complete for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1045         }
1046     }
1047     if (packet[0] == HCI_EVENT_COMMAND_STATUS){
1048         uint8_t  status = packet[2];
1049         uint16_t opcode = READ_BT_16(packet,4);
1050         if (opcode == hci_stack->last_cmd_opcode){
1051             if (status){
1052                 command_completed = 1;
1053                 log_error("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1054             } else {
1055                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1056             }
1057         } else {
1058             log_info("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1059         }
1060     }
1061     // Vendor == CSR
1062     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && packet[0] == HCI_EVENT_VENDOR_SPECIFIC){
1063         // TODO: track actual command
1064         command_completed = 1;
1065     }
1066 
1067     if (!command_completed) return;
1068 
1069     int need_baud_change = hci_stack->config
1070                         && hci_stack->control
1071                         && hci_stack->control->baudrate_cmd
1072                         && hci_stack->hci_transport->set_baudrate
1073                         && ((hci_uart_config_t *)hci_stack->config)->baudrate_main;
1074 
1075     int need_addr_change = hci_stack->custom_bd_addr_set
1076                         && hci_stack->control
1077                         && hci_stack->control->set_bd_addr_cmd;
1078 
1079     switch(hci_stack->substate){
1080         case HCI_INIT_W4_SEND_RESET:
1081             run_loop_remove_timer(&hci_stack->timeout);
1082             break;
1083         case HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION:
1084             if (need_addr_change){
1085                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1086                 return;
1087             }
1088             // skipping addr change
1089             if (need_baud_change){
1090                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1091                 return;
1092             }
1093             // also skip baud change
1094             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1095             return;
1096         case HCI_INIT_W4_SET_BD_ADDR:
1097             // for STLC2500D, bd addr change only gets active after sending reset command
1098             if (hci_stack->manufacturer == 0x0030){
1099                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1100                 return;
1101             }
1102             // skipping warm boot on STLC2500D
1103             if (need_baud_change){
1104                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1105                 return;
1106             }
1107             // skipping baud change
1108             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1109             return;
1110         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1111             if (need_baud_change){
1112                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1113                 return;
1114             }
1115             // skipping baud change
1116             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1117             return;
1118         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1119             // for STLC2500D, baud rate change already happened.
1120             // for CC256x, baud rate gets changed now
1121             if (hci_stack->manufacturer != 0x0030){
1122                 uint32_t new_baud = ((hci_uart_config_t *)hci_stack->config)->baudrate_main;
1123                 log_info("Local baud rate change to %"PRIu32, new_baud);
1124                 hci_stack->hci_transport->set_baudrate(new_baud);
1125             }
1126             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1127             return;
1128         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1129             run_loop_remove_timer(&hci_stack->timeout);
1130             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1131             return;
1132         case HCI_INIT_W4_CUSTOM_INIT:
1133             // repeat custom init
1134             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1135             return;
1136         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1137             // skip read buffer size if not supported
1138             if (hci_stack->local_supported_commands[0] & 0x01) break;
1139             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATUES;
1140             return;
1141         case HCI_INIT_W4_SET_EVENT_MASK:
1142             // skip Classic init commands for LE only chipsets
1143             if (!hci_classic_supported()){
1144                 if (hci_le_supported()){
1145                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1146                     return;
1147                 } else {
1148                     log_error("Neither BR/EDR nor LE supported");
1149                     hci_stack->substate = HCI_INIT_DONE; // skip all
1150                     return;
1151                 }
1152             }
1153             if (!hci_ssp_supported()){
1154                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1155                 return;
1156             }
1157             break;
1158         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1159             // skip write le host if not supported (e.g. on LE only EM9301)
1160             if (hci_stack->local_supported_commands[0] & 0x02) break;
1161             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1162             return;
1163         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1164             if (!hci_le_supported()){
1165                 // SKIP LE init for Classic only configuration
1166                 hci_stack->substate = HCI_INIT_DONE;
1167                 return;
1168             }
1169         default:
1170             break;
1171     }
1172     hci_initializing_next_state();
1173 }
1174 
1175 
1176 // avoid huge local variables
1177 #ifndef EMBEDDED
1178 static device_name_t device_name;
1179 #endif
1180 static void event_handler(uint8_t *packet, int size){
1181 
1182     uint16_t event_length = packet[1];
1183 
1184     // assert packet is complete
1185     if (size != event_length + 2){
1186         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
1187         return;
1188     }
1189 
1190     bd_addr_t addr;
1191     bd_addr_type_t addr_type;
1192     uint8_t link_type;
1193     hci_con_handle_t handle;
1194     hci_connection_t * conn;
1195     int i;
1196 
1197     // log_info("HCI:EVENT:%02x", packet[0]);
1198 
1199     switch (packet[0]) {
1200 
1201         case HCI_EVENT_COMMAND_COMPLETE:
1202             // get num cmd packets
1203             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u", hci_stack->num_cmd_packets, packet[2]);
1204             hci_stack->num_cmd_packets = packet[2];
1205 
1206             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
1207                 // from offset 5
1208                 // status
1209                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1210                 hci_stack->acl_data_packet_length = READ_BT_16(packet, 6);
1211                 hci_stack->sco_data_packet_length = packet[8];
1212                 hci_stack->acl_packets_total_num  = READ_BT_16(packet, 9);
1213                 hci_stack->sco_packets_total_num  = READ_BT_16(packet, 11);
1214 
1215                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1216                     // determine usable ACL payload size
1217                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1218                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1219                     }
1220                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1221                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1222                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1223                 }
1224             }
1225 #ifdef HAVE_BLE
1226             if (COMMAND_COMPLETE_EVENT(packet, hci_le_read_buffer_size)){
1227                 hci_stack->le_data_packets_length = READ_BT_16(packet, 6);
1228                 hci_stack->le_acl_packets_total_num  = packet[8];
1229                     // determine usable ACL payload size
1230                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1231                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1232                     }
1233                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1234             }
1235             if (COMMAND_COMPLETE_EVENT(packet, hci_le_read_white_list_size)){
1236                 hci_stack->le_whitelist_capacity = READ_BT_16(packet, 6);
1237                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1238             }
1239 #endif
1240             // Dump local address
1241             if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)) {
1242                 bt_flip_addr(hci_stack->local_bd_addr, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1]);
1243                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1244                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1245             }
1246             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
1247                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1248             }
1249             // Note: HCI init checks
1250             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_features)){
1251                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1252 
1253                 // determine usable ACL packet types based on host buffer size and supported features
1254                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1255                 log_info("packet types %04x", hci_stack->packet_types);
1256 
1257                 // Classic/LE
1258                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1259             }
1260             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_version_information)){
1261                 // hci_stack->hci_version    = READ_BT_16(packet, 4);
1262                 // hci_stack->hci_revision   = READ_BT_16(packet, 6);
1263                 // hci_stack->lmp_version    = READ_BT_16(packet, 8);
1264                 hci_stack->manufacturer   = READ_BT_16(packet, 10);
1265                 // hci_stack->lmp_subversion = READ_BT_16(packet, 12);
1266                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1267             }
1268             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_commands)){
1269                 hci_stack->local_supported_commands[0] =
1270                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0X80) >> 7 |  // Octet 14, bit 7
1271                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5;   // Octet 24, bit 6
1272             }
1273             break;
1274 
1275         case HCI_EVENT_COMMAND_STATUS:
1276             // get num cmd packets
1277             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u", hci_stack->num_cmd_packets, packet[3]);
1278             hci_stack->num_cmd_packets = packet[3];
1279             break;
1280 
1281         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1282             int offset = 3;
1283             for (i=0; i<packet[2];i++){
1284                 handle = READ_BT_16(packet, offset);
1285                 offset += 2;
1286                 uint16_t num_packets = READ_BT_16(packet, offset);
1287                 offset += 2;
1288 
1289                 conn = hci_connection_for_handle(handle);
1290                 if (!conn){
1291                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1292                     continue;
1293                 }
1294 
1295                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1296                     if (conn->num_sco_packets_sent >= num_packets){
1297                         conn->num_sco_packets_sent -= num_packets;
1298                     } else {
1299                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1300                         conn->num_sco_packets_sent = 0;
1301                     }
1302 
1303                 } else {
1304                     if (conn->num_acl_packets_sent >= num_packets){
1305                         conn->num_acl_packets_sent -= num_packets;
1306                     } else {
1307                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1308                         conn->num_acl_packets_sent = 0;
1309                     }
1310                 }
1311                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1312             }
1313             break;
1314         }
1315         case HCI_EVENT_CONNECTION_REQUEST:
1316             bt_flip_addr(addr, &packet[2]);
1317             // TODO: eval COD 8-10
1318             link_type = packet[11];
1319             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1320             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1321             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1322             if (!conn) {
1323                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1324             }
1325             if (!conn) {
1326                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1327                 hci_stack->decline_reason = 0x0d;
1328                 BD_ADDR_COPY(hci_stack->decline_addr, addr);
1329                 break;
1330             }
1331             conn->role  = HCI_ROLE_SLAVE;
1332             conn->state = RECEIVED_CONNECTION_REQUEST;
1333             // store info about eSCO
1334             if (link_type == 0x02){
1335                 conn->remote_supported_feature_eSCO = 1;
1336             }
1337             hci_run();
1338             break;
1339 
1340         case HCI_EVENT_CONNECTION_COMPLETE:
1341             // Connection management
1342             bt_flip_addr(addr, &packet[5]);
1343             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1344             addr_type = BD_ADDR_TYPE_CLASSIC;
1345             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1346             if (conn) {
1347                 if (!packet[2]){
1348                     conn->state = OPEN;
1349                     conn->con_handle = READ_BT_16(packet, 3);
1350                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1351 
1352                     // restart timer
1353                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1354                     run_loop_add_timer(&conn->timeout);
1355 
1356                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1357 
1358                     hci_emit_nr_connections_changed();
1359                 } else {
1360                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1361                     uint8_t status = packet[2];
1362                     bd_addr_t bd_address;
1363                     memcpy(&bd_address, conn->address, 6);
1364 
1365                     // connection failed, remove entry
1366                     linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
1367                     btstack_memory_hci_connection_free( conn );
1368 
1369                     // notify client if dedicated bonding
1370                     if (notify_dedicated_bonding_failed){
1371                         log_info("hci notify_dedicated_bonding_failed");
1372                         hci_emit_dedicated_bonding_result(bd_address, status);
1373                     }
1374 
1375                     // if authentication error, also delete link key
1376                     if (packet[2] == 0x05) {
1377                         hci_drop_link_key_for_bd_addr(addr);
1378                     }
1379                 }
1380             }
1381             break;
1382 
1383         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1384             bt_flip_addr(addr, &packet[5]);
1385             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1386             if (packet[2]){
1387                 // connection failed
1388                 break;
1389             }
1390             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1391             if (!conn) {
1392                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1393             }
1394             if (!conn) {
1395                 break;
1396             }
1397             conn->state = OPEN;
1398             conn->con_handle = READ_BT_16(packet, 3);
1399             break;
1400 
1401         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1402             handle = READ_BT_16(packet, 3);
1403             conn = hci_connection_for_handle(handle);
1404             if (!conn) break;
1405             if (!packet[2]){
1406                 uint8_t * features = &packet[5];
1407                 if (features[6] & (1 << 3)){
1408                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1409                 }
1410                 if (features[3] & (1<<7)){
1411                     conn->remote_supported_feature_eSCO = 1;
1412                 }
1413             }
1414             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1415             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1416             if (conn->bonding_flags & BONDING_DEDICATED){
1417                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1418             }
1419             break;
1420 
1421         case HCI_EVENT_LINK_KEY_REQUEST:
1422             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1423             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1424             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1425             if (hci_stack->bondable && !hci_stack->remote_device_db) break;
1426             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1427             hci_run();
1428             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1429             return;
1430 
1431         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1432             bt_flip_addr(addr, &packet[2]);
1433             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1434             if (!conn) break;
1435             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1436             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1437             // Change Connection Encryption keeps link key type
1438             if (link_key_type != CHANGED_COMBINATION_KEY){
1439                 conn->link_key_type = link_key_type;
1440             }
1441             if (!hci_stack->remote_device_db) break;
1442             hci_stack->remote_device_db->put_link_key(addr, &packet[8], conn->link_key_type);
1443             // still forward event to allow dismiss of pairing dialog
1444             break;
1445         }
1446 
1447         case HCI_EVENT_PIN_CODE_REQUEST:
1448             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1449             // non-bondable mode: pin code negative reply will be sent
1450             if (!hci_stack->bondable){
1451                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1452                 hci_run();
1453                 return;
1454             }
1455             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1456             if (!hci_stack->remote_device_db) break;
1457             bt_flip_addr(addr, &packet[2]);
1458             hci_stack->remote_device_db->delete_link_key(addr);
1459             break;
1460 
1461         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1462             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1463             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1464             break;
1465 
1466         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1467             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1468             if (!hci_stack->ssp_auto_accept) break;
1469             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1470             break;
1471 
1472         case HCI_EVENT_USER_PASSKEY_REQUEST:
1473             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1474             if (!hci_stack->ssp_auto_accept) break;
1475             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1476             break;
1477 
1478         case HCI_EVENT_ENCRYPTION_CHANGE:
1479             handle = READ_BT_16(packet, 3);
1480             conn = hci_connection_for_handle(handle);
1481             if (!conn) break;
1482             if (packet[2] == 0) {
1483                 if (packet[5]){
1484                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1485                 } else {
1486                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1487                 }
1488             }
1489             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1490             break;
1491 
1492         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1493             handle = READ_BT_16(packet, 3);
1494             conn = hci_connection_for_handle(handle);
1495             if (!conn) break;
1496 
1497             // dedicated bonding: send result and disconnect
1498             if (conn->bonding_flags & BONDING_DEDICATED){
1499                 conn->bonding_flags &= ~BONDING_DEDICATED;
1500                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1501                 conn->bonding_status = packet[2];
1502                 break;
1503             }
1504 
1505             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1506                 // link key sufficient for requested security
1507                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1508                 break;
1509             }
1510             // not enough
1511             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1512             break;
1513 
1514 #ifndef EMBEDDED
1515         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
1516             if (!hci_stack->remote_device_db) break;
1517             if (packet[2]) break; // status not ok
1518             bt_flip_addr(addr, &packet[3]);
1519             // fix for invalid remote names - terminate on 0xff
1520             for (i=0; i<248;i++){
1521                 if (packet[9+i] == 0xff){
1522                     packet[9+i] = 0;
1523                     break;
1524                 }
1525             }
1526             memset(&device_name, 0, sizeof(device_name_t));
1527             strncpy((char*) device_name, (char*) &packet[9], 248);
1528             hci_stack->remote_device_db->put_name(addr, &device_name);
1529             break;
1530 
1531         case HCI_EVENT_INQUIRY_RESULT:
1532         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:{
1533             if (!hci_stack->remote_device_db) break;
1534             // first send inq result packet
1535             hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
1536             // then send cached remote names
1537             int offset = 3;
1538             for (i=0; i<packet[2];i++){
1539                 bt_flip_addr(addr, &packet[offset]);
1540                 offset += 14; // 6 + 1 + 1 + 1 + 3 + 2;
1541                 if (hci_stack->remote_device_db->get_name(addr, &device_name)){
1542                     hci_emit_remote_name_cached(addr, &device_name);
1543                 }
1544             }
1545             return;
1546         }
1547 #endif
1548 
1549         // HCI_EVENT_DISCONNECTION_COMPLETE
1550         // has been split, to first notify stack before shutting connection down
1551         // see end of function, too.
1552         case HCI_EVENT_DISCONNECTION_COMPLETE:
1553             if (packet[2]) break;   // status != 0
1554             handle = READ_BT_16(packet, 3);
1555             conn = hci_connection_for_handle(handle);
1556             if (!conn) break;       // no conn struct anymore
1557             // re-enable advertisements for le connections if active
1558             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1559                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1560             }
1561             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1562             break;
1563 
1564         case HCI_EVENT_HARDWARE_ERROR:
1565             if (hci_stack->hardware_error_callback){
1566                 (*hci_stack->hardware_error_callback)();
1567             } else if(hci_stack->control && hci_stack->control->hw_error){
1568                 (*hci_stack->control->hw_error)();
1569             } else {
1570                 // if no special requests, just reboot stack
1571                 hci_power_control_off();
1572                 hci_power_control_on();
1573             }
1574             break;
1575 
1576         case HCI_EVENT_ROLE_CHANGE:
1577             if (packet[2]) break;   // status != 0
1578             handle = READ_BT_16(packet, 3);
1579             conn = hci_connection_for_handle(handle);
1580             if (!conn) break;       // no conn
1581             conn->role = packet[9];
1582             break;
1583 
1584         case DAEMON_EVENT_HCI_PACKET_SENT:
1585             // release packet buffer only for asynchronous transport and if there are not further fragements
1586             if (hci_transport_synchronous()) {
1587                 log_error("Synchronous HCI Transport shouldn't send DAEMON_EVENT_HCI_PACKET_SENT");
1588                 return; // instead of break: to avoid re-entering hci_run()
1589             }
1590             if (hci_stack->acl_fragmentation_total_size) break;
1591             hci_release_packet_buffer();
1592             break;
1593 
1594 #ifdef HAVE_BLE
1595         case HCI_EVENT_LE_META:
1596             switch (packet[2]){
1597                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1598                     log_info("advertising report received");
1599                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1600                     le_handle_advertisement_report(packet, size);
1601                     break;
1602                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1603                     // Connection management
1604                     bt_flip_addr(addr, &packet[8]);
1605                     addr_type = (bd_addr_type_t)packet[7];
1606                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1607                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1608                     // if auto-connect, remove from whitelist in both roles
1609                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1610                         hci_remove_from_whitelist(addr_type, addr);
1611                     }
1612                     // handle error: error is reported only to the initiator -> outgoing connection
1613                     if (packet[3]){
1614                         // outgoing connection establishment is done
1615                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1616                         // remove entry
1617                         if (conn){
1618                             linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
1619                             btstack_memory_hci_connection_free( conn );
1620                         }
1621                         break;
1622                     }
1623                     // on success, both hosts receive connection complete event
1624                     if (packet[6] == HCI_ROLE_MASTER){
1625                         // if we're master, it was an outgoing connection and we're done with it
1626                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1627                     } else {
1628                         // if we're slave, it was an incoming connection, advertisements have stopped
1629                         hci_stack->le_advertisements_active = 0;
1630                     }
1631                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1632                     if (!conn){
1633                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1634                     }
1635                     // no memory, sorry.
1636                     if (!conn){
1637                         break;
1638                     }
1639 
1640                     conn->state = OPEN;
1641                     conn->role  = packet[6];
1642                     conn->con_handle = READ_BT_16(packet, 4);
1643 
1644                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1645 
1646                     // restart timer
1647                     // run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1648                     // run_loop_add_timer(&conn->timeout);
1649 
1650                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1651 
1652                     hci_emit_nr_connections_changed();
1653                     break;
1654 
1655             // log_info("LE buffer size: %u, count %u", READ_BT_16(packet,6), packet[8]);
1656 
1657                 default:
1658                     break;
1659             }
1660             break;
1661 #endif
1662         default:
1663             break;
1664     }
1665 
1666     // handle BT initialization
1667     if (hci_stack->state == HCI_STATE_INITIALIZING){
1668         hci_initializing_event_handler(packet, size);
1669     }
1670 
1671     // help with BT sleep
1672     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
1673         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
1674         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
1675         hci_initializing_next_state();
1676     }
1677 
1678     // notify upper stack
1679     hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
1680 
1681     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
1682     if (packet[0] == HCI_EVENT_DISCONNECTION_COMPLETE){
1683         if (!packet[2]){
1684             handle = READ_BT_16(packet, 3);
1685             hci_connection_t * aConn = hci_connection_for_handle(handle);
1686             if (aConn) {
1687                 uint8_t status = aConn->bonding_status;
1688                 uint16_t flags = aConn->bonding_flags;
1689                 bd_addr_t bd_address;
1690                 memcpy(&bd_address, aConn->address, 6);
1691                 hci_shutdown_connection(aConn);
1692                 // connection struct is gone, don't access anymore
1693                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
1694                     hci_emit_dedicated_bonding_result(bd_address, status);
1695                 }
1696             }
1697         }
1698     }
1699 
1700 	// execute main loop
1701 	hci_run();
1702 }
1703 
1704 static void sco_handler(uint8_t * packet, uint16_t size){
1705     if (!hci_stack->sco_packet_handler) return;
1706     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, packet, size);
1707 }
1708 
1709 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
1710     hci_dump_packet(packet_type, 1, packet, size);
1711     switch (packet_type) {
1712         case HCI_EVENT_PACKET:
1713             event_handler(packet, size);
1714             break;
1715         case HCI_ACL_DATA_PACKET:
1716             acl_handler(packet, size);
1717             break;
1718         case HCI_SCO_DATA_PACKET:
1719             sco_handler(packet, size);
1720         default:
1721             break;
1722     }
1723 }
1724 
1725 /** Register HCI packet handlers */
1726 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
1727     hci_stack->packet_handler = handler;
1728 }
1729 
1730 /**
1731  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
1732  */
1733 void hci_register_sco_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
1734     hci_stack->sco_packet_handler = handler;
1735 }
1736 
1737 static void hci_state_reset(void){
1738     // no connections yet
1739     hci_stack->connections = NULL;
1740 
1741     // keep discoverable/connectable as this has been requested by the client(s)
1742     // hci_stack->discoverable = 0;
1743     // hci_stack->connectable = 0;
1744     // hci_stack->bondable = 1;
1745 
1746     // buffer is free
1747     hci_stack->hci_packet_buffer_reserved = 0;
1748 
1749     // no pending cmds
1750     hci_stack->decline_reason = 0;
1751     hci_stack->new_scan_enable_value = 0xff;
1752 
1753     // LE
1754     hci_stack->adv_addr_type = 0;
1755     memset(hci_stack->adv_address, 0, 6);
1756     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1757     hci_stack->le_scan_type = 0xff;
1758     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1759     hci_stack->le_whitelist = 0;
1760     hci_stack->le_whitelist_capacity = 0;
1761     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
1762     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
1763     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
1764     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
1765     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
1766     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
1767 }
1768 
1769 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t const* remote_device_db){
1770 
1771 #ifdef HAVE_MALLOC
1772     if (!hci_stack) {
1773         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
1774     }
1775 #else
1776     hci_stack = &hci_stack_static;
1777 #endif
1778     memset(hci_stack, 0, sizeof(hci_stack_t));
1779 
1780     // reference to use transport layer implementation
1781     hci_stack->hci_transport = transport;
1782 
1783     // references to used control implementation
1784     hci_stack->control = control;
1785 
1786     // reference to used config
1787     hci_stack->config = config;
1788 
1789     // higher level handler
1790     hci_stack->packet_handler = dummy_handler;
1791 
1792     // store and open remote device db
1793     hci_stack->remote_device_db = remote_device_db;
1794     if (hci_stack->remote_device_db) {
1795         hci_stack->remote_device_db->open();
1796     }
1797 
1798     // max acl payload size defined in config.h
1799     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1800 
1801     // register packet handlers with transport
1802     transport->register_packet_handler(&packet_handler);
1803 
1804     hci_stack->state = HCI_STATE_OFF;
1805 
1806     // class of device
1807     hci_stack->class_of_device = 0x007a020c; // Smartphone
1808 
1809     // bondable by default
1810     hci_stack->bondable = 1;
1811 
1812     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
1813     hci_stack->ssp_enable = 1;
1814     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
1815     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
1816     hci_stack->ssp_auto_accept = 1;
1817 
1818     // voice setting - signed 8 bit pcm data with CVSD over the air
1819     hci_stack->sco_voice_setting = 0x40;
1820 
1821     hci_state_reset();
1822 }
1823 
1824 void hci_close(void){
1825     // close remote device db
1826     if (hci_stack->remote_device_db) {
1827         hci_stack->remote_device_db->close();
1828     }
1829     while (hci_stack->connections) {
1830         // cancel all l2cap connections
1831         hci_emit_disconnection_complete(((hci_connection_t *) hci_stack->connections)->con_handle, 0x16); // terminated by local host
1832         hci_shutdown_connection((hci_connection_t *) hci_stack->connections);
1833     }
1834     hci_power_control(HCI_POWER_OFF);
1835 
1836 #ifdef HAVE_MALLOC
1837     free(hci_stack);
1838 #endif
1839     hci_stack = NULL;
1840 }
1841 
1842 void hci_set_class_of_device(uint32_t class_of_device){
1843     hci_stack->class_of_device = class_of_device;
1844 }
1845 
1846 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
1847 void hci_set_bd_addr(bd_addr_t addr){
1848     memcpy(hci_stack->custom_bd_addr, addr, 6);
1849     hci_stack->custom_bd_addr_set = 1;
1850 }
1851 
1852 void hci_disable_l2cap_timeout_check(void){
1853     disable_l2cap_timeouts = 1;
1854 }
1855 // State-Module-Driver overview
1856 // state                    module  low-level
1857 // HCI_STATE_OFF             off      close
1858 // HCI_STATE_INITIALIZING,   on       open
1859 // HCI_STATE_WORKING,        on       open
1860 // HCI_STATE_HALTING,        on       open
1861 // HCI_STATE_SLEEPING,    off/sleep   close
1862 // HCI_STATE_FALLING_ASLEEP  on       open
1863 
1864 static int hci_power_control_on(void){
1865 
1866     // power on
1867     int err = 0;
1868     if (hci_stack->control && hci_stack->control->on){
1869         err = (*hci_stack->control->on)(hci_stack->config);
1870     }
1871     if (err){
1872         log_error( "POWER_ON failed");
1873         hci_emit_hci_open_failed();
1874         return err;
1875     }
1876 
1877     // open low-level device
1878     err = hci_stack->hci_transport->open(hci_stack->config);
1879     if (err){
1880         log_error( "HCI_INIT failed, turning Bluetooth off again");
1881         if (hci_stack->control && hci_stack->control->off){
1882             (*hci_stack->control->off)(hci_stack->config);
1883         }
1884         hci_emit_hci_open_failed();
1885         return err;
1886     }
1887     return 0;
1888 }
1889 
1890 static void hci_power_control_off(void){
1891 
1892     log_info("hci_power_control_off");
1893 
1894     // close low-level device
1895     hci_stack->hci_transport->close(hci_stack->config);
1896 
1897     log_info("hci_power_control_off - hci_transport closed");
1898 
1899     // power off
1900     if (hci_stack->control && hci_stack->control->off){
1901         (*hci_stack->control->off)(hci_stack->config);
1902     }
1903 
1904     log_info("hci_power_control_off - control closed");
1905 
1906     hci_stack->state = HCI_STATE_OFF;
1907 }
1908 
1909 static void hci_power_control_sleep(void){
1910 
1911     log_info("hci_power_control_sleep");
1912 
1913 #if 0
1914     // don't close serial port during sleep
1915 
1916     // close low-level device
1917     hci_stack->hci_transport->close(hci_stack->config);
1918 #endif
1919 
1920     // sleep mode
1921     if (hci_stack->control && hci_stack->control->sleep){
1922         (*hci_stack->control->sleep)(hci_stack->config);
1923     }
1924 
1925     hci_stack->state = HCI_STATE_SLEEPING;
1926 }
1927 
1928 static int hci_power_control_wake(void){
1929 
1930     log_info("hci_power_control_wake");
1931 
1932     // wake on
1933     if (hci_stack->control && hci_stack->control->wake){
1934         (*hci_stack->control->wake)(hci_stack->config);
1935     }
1936 
1937 #if 0
1938     // open low-level device
1939     int err = hci_stack->hci_transport->open(hci_stack->config);
1940     if (err){
1941         log_error( "HCI_INIT failed, turning Bluetooth off again");
1942         if (hci_stack->control && hci_stack->control->off){
1943             (*hci_stack->control->off)(hci_stack->config);
1944         }
1945         hci_emit_hci_open_failed();
1946         return err;
1947     }
1948 #endif
1949 
1950     return 0;
1951 }
1952 
1953 static void hci_power_transition_to_initializing(void){
1954     // set up state machine
1955     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1956     hci_stack->hci_packet_buffer_reserved = 0;
1957     hci_stack->state = HCI_STATE_INITIALIZING;
1958     hci_stack->substate = HCI_INIT_SEND_RESET;
1959 }
1960 
1961 int hci_power_control(HCI_POWER_MODE power_mode){
1962 
1963     log_info("hci_power_control: %u, current mode %u", power_mode, hci_stack->state);
1964 
1965     int err = 0;
1966     switch (hci_stack->state){
1967 
1968         case HCI_STATE_OFF:
1969             switch (power_mode){
1970                 case HCI_POWER_ON:
1971                     err = hci_power_control_on();
1972                     if (err) {
1973                         log_error("hci_power_control_on() error %u", err);
1974                         return err;
1975                     }
1976                     hci_power_transition_to_initializing();
1977                     break;
1978                 case HCI_POWER_OFF:
1979                     // do nothing
1980                     break;
1981                 case HCI_POWER_SLEEP:
1982                     // do nothing (with SLEEP == OFF)
1983                     break;
1984             }
1985             break;
1986 
1987         case HCI_STATE_INITIALIZING:
1988             switch (power_mode){
1989                 case HCI_POWER_ON:
1990                     // do nothing
1991                     break;
1992                 case HCI_POWER_OFF:
1993                     // no connections yet, just turn it off
1994                     hci_power_control_off();
1995                     break;
1996                 case HCI_POWER_SLEEP:
1997                     // no connections yet, just turn it off
1998                     hci_power_control_sleep();
1999                     break;
2000             }
2001             break;
2002 
2003         case HCI_STATE_WORKING:
2004             switch (power_mode){
2005                 case HCI_POWER_ON:
2006                     // do nothing
2007                     break;
2008                 case HCI_POWER_OFF:
2009                     // see hci_run
2010                     hci_stack->state = HCI_STATE_HALTING;
2011                     break;
2012                 case HCI_POWER_SLEEP:
2013                     // see hci_run
2014                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2015                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2016                     break;
2017             }
2018             break;
2019 
2020         case HCI_STATE_HALTING:
2021             switch (power_mode){
2022                 case HCI_POWER_ON:
2023                     hci_power_transition_to_initializing();
2024                     break;
2025                 case HCI_POWER_OFF:
2026                     // do nothing
2027                     break;
2028                 case HCI_POWER_SLEEP:
2029                     // see hci_run
2030                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2031                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2032                     break;
2033             }
2034             break;
2035 
2036         case HCI_STATE_FALLING_ASLEEP:
2037             switch (power_mode){
2038                 case HCI_POWER_ON:
2039 
2040 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
2041                     // nothing to do, if H4 supports power management
2042                     if (bt_control_iphone_power_management_enabled()){
2043                         hci_stack->state = HCI_STATE_INITIALIZING;
2044                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2045                         break;
2046                     }
2047 #endif
2048                     hci_power_transition_to_initializing();
2049                     break;
2050                 case HCI_POWER_OFF:
2051                     // see hci_run
2052                     hci_stack->state = HCI_STATE_HALTING;
2053                     break;
2054                 case HCI_POWER_SLEEP:
2055                     // do nothing
2056                     break;
2057             }
2058             break;
2059 
2060         case HCI_STATE_SLEEPING:
2061             switch (power_mode){
2062                 case HCI_POWER_ON:
2063 
2064 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
2065                     // nothing to do, if H4 supports power management
2066                     if (bt_control_iphone_power_management_enabled()){
2067                         hci_stack->state = HCI_STATE_INITIALIZING;
2068                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2069                         hci_update_scan_enable();
2070                         break;
2071                     }
2072 #endif
2073                     err = hci_power_control_wake();
2074                     if (err) return err;
2075                     hci_power_transition_to_initializing();
2076                     break;
2077                 case HCI_POWER_OFF:
2078                     hci_stack->state = HCI_STATE_HALTING;
2079                     break;
2080                 case HCI_POWER_SLEEP:
2081                     // do nothing
2082                     break;
2083             }
2084             break;
2085     }
2086 
2087     // create internal event
2088 	hci_emit_state();
2089 
2090 	// trigger next/first action
2091 	hci_run();
2092 
2093     return 0;
2094 }
2095 
2096 static void hci_update_scan_enable(void){
2097     // 2 = page scan, 1 = inq scan
2098     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2099     hci_run();
2100 }
2101 
2102 void hci_discoverable_control(uint8_t enable){
2103     if (enable) enable = 1; // normalize argument
2104 
2105     if (hci_stack->discoverable == enable){
2106         hci_emit_discoverable_enabled(hci_stack->discoverable);
2107         return;
2108     }
2109 
2110     hci_stack->discoverable = enable;
2111     hci_update_scan_enable();
2112 }
2113 
2114 void hci_connectable_control(uint8_t enable){
2115     if (enable) enable = 1; // normalize argument
2116 
2117     // don't emit event
2118     if (hci_stack->connectable == enable) return;
2119 
2120     hci_stack->connectable = enable;
2121     hci_update_scan_enable();
2122 }
2123 
2124 void hci_local_bd_addr(bd_addr_t address_buffer){
2125     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2126 }
2127 
2128 void hci_run(void){
2129 
2130     // log_info("hci_run: entered");
2131     linked_item_t * it;
2132 
2133     // send continuation fragments first, as they block the prepared packet buffer
2134     if (hci_stack->acl_fragmentation_total_size > 0) {
2135         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2136         if (hci_can_send_prepared_acl_packet_now(con_handle)){
2137             hci_connection_t *connection = hci_connection_for_handle(con_handle);
2138             if (connection) {
2139                 hci_send_acl_packet_fragments(connection);
2140                 return;
2141             }
2142             // connection gone -> discard further fragments
2143             hci_stack->acl_fragmentation_total_size = 0;
2144             hci_stack->acl_fragmentation_pos = 0;
2145         }
2146     }
2147 
2148     if (!hci_can_send_command_packet_now()) return;
2149 
2150     // global/non-connection oriented commands
2151 
2152     // decline incoming connections
2153     if (hci_stack->decline_reason){
2154         uint8_t reason = hci_stack->decline_reason;
2155         hci_stack->decline_reason = 0;
2156         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2157         return;
2158     }
2159 
2160     // send scan enable
2161     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2162         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2163         hci_stack->new_scan_enable_value = 0xff;
2164         return;
2165     }
2166 
2167 #ifdef HAVE_BLE
2168     if (hci_stack->state == HCI_STATE_WORKING){
2169         // handle le scan
2170         switch(hci_stack->le_scanning_state){
2171             case LE_START_SCAN:
2172                 hci_stack->le_scanning_state = LE_SCANNING;
2173                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2174                 return;
2175 
2176             case LE_STOP_SCAN:
2177                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2178                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2179                 return;
2180             default:
2181                 break;
2182         }
2183         if (hci_stack->le_scan_type != 0xff){
2184             // defaults: active scanning, accept all advertisement packets
2185             int scan_type = hci_stack->le_scan_type;
2186             hci_stack->le_scan_type = 0xff;
2187             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->adv_addr_type, 0);
2188             return;
2189         }
2190         // le advertisement control
2191         if (hci_stack->le_advertisements_todo){
2192             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2193         }
2194         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2195             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2196             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2197             return;
2198         }
2199         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2200             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2201             hci_send_cmd(&hci_le_set_advertising_parameters,
2202                  hci_stack->le_advertisements_interval_min,
2203                  hci_stack->le_advertisements_interval_max,
2204                  hci_stack->le_advertisements_type,
2205                  hci_stack->le_advertisements_own_address_type,
2206                  hci_stack->le_advertisements_direct_address_type,
2207                  hci_stack->le_advertisements_direct_address,
2208                  hci_stack->le_advertisements_channel_map,
2209                  hci_stack->le_advertisements_filter_policy);
2210             return;
2211         }
2212         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_DATA){
2213             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_DATA;
2214             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2215                 hci_stack->le_advertisements_data);
2216             return;
2217         }
2218         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2219             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2220             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2221             return;
2222         }
2223 
2224         //
2225         // LE Whitelist Management
2226         //
2227 
2228         // check if whitelist needs modification
2229         linked_list_iterator_t lit;
2230         int modification_pending = 0;
2231         linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2232         while (linked_list_iterator_has_next(&lit)){
2233             whitelist_entry_t * entry = (whitelist_entry_t*) linked_list_iterator_next(&lit);
2234             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2235                 modification_pending = 1;
2236                 break;
2237             }
2238         }
2239 
2240         if (modification_pending){
2241             // stop connnecting if modification pending
2242             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2243                 hci_send_cmd(&hci_le_create_connection_cancel);
2244                 return;
2245             }
2246 
2247             // add/remove entries
2248             linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2249             while (linked_list_iterator_has_next(&lit)){
2250                 whitelist_entry_t * entry = (whitelist_entry_t*) linked_list_iterator_next(&lit);
2251                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2252                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2253                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2254                     return;
2255 
2256                 }
2257                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2258                     bd_addr_t address;
2259                     bd_addr_type_t address_type = entry->address_type;
2260                     memcpy(address, entry->address, 6);
2261                     linked_list_remove(&hci_stack->le_whitelist, (linked_item_t *) entry);
2262                     btstack_memory_whitelist_entry_free(entry);
2263                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2264                     return;
2265                 }
2266             }
2267         }
2268 
2269         // start connecting
2270         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2271             !linked_list_empty(&hci_stack->le_whitelist)){
2272             bd_addr_t null_addr;
2273             memset(null_addr, 0, 6);
2274             hci_send_cmd(&hci_le_create_connection,
2275                  0x0060,    // scan interval: 60 ms
2276                  0x0030,    // scan interval: 30 ms
2277                  1,         // use whitelist
2278                  0,         // peer address type
2279                  null_addr,      // peer bd addr
2280                  hci_stack->adv_addr_type, // our addr type:
2281                  0x0008,    // conn interval min
2282                  0x0018,    // conn interval max
2283                  0,         // conn latency
2284                  0x0048,    // supervision timeout
2285                  0x0001,    // min ce length
2286                  0x0001     // max ce length
2287                  );
2288             return;
2289         }
2290     }
2291 #endif
2292 
2293     // send pending HCI commands
2294     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
2295         hci_connection_t * connection = (hci_connection_t *) it;
2296 
2297         switch(connection->state){
2298             case SEND_CREATE_CONNECTION:
2299                 switch(connection->address_type){
2300                     case BD_ADDR_TYPE_CLASSIC:
2301                         log_info("sending hci_create_connection");
2302                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2303                         break;
2304                     default:
2305 #ifdef HAVE_BLE
2306                         log_info("sending hci_le_create_connection");
2307                         hci_send_cmd(&hci_le_create_connection,
2308                                      0x0060,    // scan interval: 60 ms
2309                                      0x0030,    // scan interval: 30 ms
2310                                      0,         // don't use whitelist
2311                                      connection->address_type, // peer address type
2312                                      connection->address,      // peer bd addr
2313                                      hci_stack->adv_addr_type, // our addr type:
2314                                      0x0008,    // conn interval min
2315                                      0x0018,    // conn interval max
2316                                      0,         // conn latency
2317                                      0x0048,    // supervision timeout
2318                                      0x0001,    // min ce length
2319                                      0x0001     // max ce length
2320                                      );
2321 
2322                         connection->state = SENT_CREATE_CONNECTION;
2323 #endif
2324                         break;
2325                 }
2326                 return;
2327 
2328             case RECEIVED_CONNECTION_REQUEST:
2329                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2330                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2331                 connection->role  = HCI_ROLE_SLAVE;
2332                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2333                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2334                 } else {
2335                     // remote supported feature eSCO is set if link type is eSCO
2336                     if (connection->remote_supported_feature_eSCO){
2337                         // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
2338                         hci_send_cmd(&hci_accept_synchronous_connection, connection->address, 8000, 8000, 0x000c, hci_stack->sco_voice_setting, 0x02, 0x388);
2339                     } else {
2340                         // SCO: max latency, retransmission interval: N/A. any packet type
2341                         hci_send_cmd(&hci_accept_synchronous_connection, connection->address, 8000, 8000, 0xffff, hci_stack->sco_voice_setting, 0xff, 0x003f);
2342                     }
2343                 }
2344                 return;
2345 
2346 #ifdef HAVE_BLE
2347             case SEND_CANCEL_CONNECTION:
2348                 connection->state = SENT_CANCEL_CONNECTION;
2349                 hci_send_cmd(&hci_le_create_connection_cancel);
2350                 return;
2351 #endif
2352             case SEND_DISCONNECT:
2353                 connection->state = SENT_DISCONNECT;
2354                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2355                 return;
2356 
2357             default:
2358                 break;
2359         }
2360 
2361         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2362             log_info("responding to link key request");
2363             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2364             link_key_t link_key;
2365             link_key_type_t link_key_type;
2366             if ( hci_stack->remote_device_db
2367               && hci_stack->remote_device_db->get_link_key(connection->address, link_key, &link_key_type)
2368               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2369                connection->link_key_type = link_key_type;
2370                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2371             } else {
2372                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2373             }
2374             return;
2375         }
2376 
2377         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2378             log_info("denying to pin request");
2379             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2380             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2381             return;
2382         }
2383 
2384         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2385             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2386             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2387             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2388                 // tweak authentication requirements
2389                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2390                 if (connection->bonding_flags & BONDING_DEDICATED){
2391                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2392                 }
2393                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2394                     authreq |= 1;
2395                 }
2396                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2397             } else {
2398                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2399             }
2400             return;
2401         }
2402 
2403         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2404             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2405             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2406             return;
2407         }
2408 
2409         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2410             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2411             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2412             return;
2413         }
2414 
2415         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2416             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2417             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2418             return;
2419         }
2420 
2421         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2422             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2423             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2424             return;
2425         }
2426         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2427             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2428             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2429             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2430             return;
2431         }
2432         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2433             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2434             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2435             return;
2436         }
2437         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2438             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2439             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2440             return;
2441         }
2442 
2443 #ifdef HAVE_BLE
2444         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2445             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2446 
2447             uint16_t connection_interval_min = connection->le_conn_interval_min;
2448             connection->le_conn_interval_min = 0;
2449             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2450                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2451                 0x0000, 0xffff);
2452         }
2453 #endif
2454     }
2455 
2456     hci_connection_t * connection;
2457     switch (hci_stack->state){
2458         case HCI_STATE_INITIALIZING:
2459             hci_initializing_run();
2460             break;
2461 
2462         case HCI_STATE_HALTING:
2463 
2464             log_info("HCI_STATE_HALTING");
2465 
2466             // free whitelist entries
2467 #ifdef HAVE_BLE
2468             {
2469                 linked_list_iterator_t lit;
2470                 linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2471                 while (linked_list_iterator_has_next(&lit)){
2472                     whitelist_entry_t * entry = (whitelist_entry_t*) linked_list_iterator_next(&lit);
2473                     linked_list_remove(&hci_stack->le_whitelist, (linked_item_t *) entry);
2474                     btstack_memory_whitelist_entry_free(entry);
2475                 }
2476             }
2477 #endif
2478             // close all open connections
2479             connection =  (hci_connection_t *) hci_stack->connections;
2480             if (connection){
2481                 uint16_t con_handle = (uint16_t) connection->con_handle;
2482                 if (!hci_can_send_command_packet_now()) return;
2483 
2484                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2485 
2486                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2487                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2488 
2489                 // ... which would be ignored anyway as we shutdown (free) the connection now
2490                 hci_shutdown_connection(connection);
2491 
2492                 // finally, send the disconnect command
2493                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2494                 return;
2495             }
2496             log_info("HCI_STATE_HALTING, calling off");
2497 
2498             // switch mode
2499             hci_power_control_off();
2500 
2501             log_info("HCI_STATE_HALTING, emitting state");
2502             hci_emit_state();
2503             log_info("HCI_STATE_HALTING, done");
2504             break;
2505 
2506         case HCI_STATE_FALLING_ASLEEP:
2507             switch(hci_stack->substate) {
2508                 case HCI_FALLING_ASLEEP_DISCONNECT:
2509                     log_info("HCI_STATE_FALLING_ASLEEP");
2510                     // close all open connections
2511                     connection =  (hci_connection_t *) hci_stack->connections;
2512 
2513 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
2514                     // don't close connections, if H4 supports power management
2515                     if (bt_control_iphone_power_management_enabled()){
2516                         connection = NULL;
2517                     }
2518 #endif
2519                     if (connection){
2520 
2521                         // send disconnect
2522                         if (!hci_can_send_command_packet_now()) return;
2523 
2524                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2525                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2526 
2527                         // send disconnected event right away - causes higher layer connections to get closed, too.
2528                         hci_shutdown_connection(connection);
2529                         return;
2530                     }
2531 
2532                     if (hci_classic_supported()){
2533                         // disable page and inquiry scan
2534                         if (!hci_can_send_command_packet_now()) return;
2535 
2536                         log_info("HCI_STATE_HALTING, disabling inq scans");
2537                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2538 
2539                         // continue in next sub state
2540                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2541                         break;
2542                     }
2543                     // fall through for ble-only chips
2544 
2545                 case HCI_FALLING_ASLEEP_COMPLETE:
2546                     log_info("HCI_STATE_HALTING, calling sleep");
2547 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
2548                     // don't actually go to sleep, if H4 supports power management
2549                     if (bt_control_iphone_power_management_enabled()){
2550                         // SLEEP MODE reached
2551                         hci_stack->state = HCI_STATE_SLEEPING;
2552                         hci_emit_state();
2553                         break;
2554                     }
2555 #endif
2556                     // switch mode
2557                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2558                     hci_emit_state();
2559                     break;
2560 
2561                 default:
2562                     break;
2563             }
2564             break;
2565 
2566         default:
2567             break;
2568     }
2569 }
2570 
2571 int hci_send_cmd_packet(uint8_t *packet, int size){
2572     bd_addr_t addr;
2573     hci_connection_t * conn;
2574     // house-keeping
2575 
2576     // create_connection?
2577     if (IS_COMMAND(packet, hci_create_connection)){
2578         bt_flip_addr(addr, &packet[3]);
2579         log_info("Create_connection to %s", bd_addr_to_str(addr));
2580 
2581         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2582         if (!conn){
2583             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2584             if (!conn){
2585                 // notify client that alloc failed
2586                 hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
2587                 return 0; // don't sent packet to controller
2588             }
2589             conn->state = SEND_CREATE_CONNECTION;
2590         }
2591         log_info("conn state %u", conn->state);
2592         switch (conn->state){
2593             // if connection active exists
2594             case OPEN:
2595                 // and OPEN, emit connection complete command, don't send to controller
2596                 hci_emit_connection_complete(conn, 0);
2597                 return 0;
2598             case SEND_CREATE_CONNECTION:
2599                 // connection created by hci, e.g. dedicated bonding
2600                 break;
2601             default:
2602                 // otherwise, just ignore as it is already in the open process
2603                 return 0;
2604         }
2605         conn->state = SENT_CREATE_CONNECTION;
2606     }
2607     if (IS_COMMAND(packet, hci_link_key_request_reply)){
2608         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
2609     }
2610     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
2611         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
2612     }
2613 
2614     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
2615         if (hci_stack->remote_device_db){
2616             bt_flip_addr(addr, &packet[3]);
2617             hci_stack->remote_device_db->delete_link_key(addr);
2618         }
2619     }
2620 
2621     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
2622     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
2623         bt_flip_addr(addr, &packet[3]);
2624         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2625         if (conn){
2626             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
2627         }
2628     }
2629 
2630     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
2631     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
2632     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
2633     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
2634         bt_flip_addr(addr, &packet[3]);
2635         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2636         if (conn){
2637             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
2638         }
2639     }
2640 
2641     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2642         hci_stack->loopback_mode = packet[3];
2643     }
2644 
2645 #ifdef HAVE_BLE
2646     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
2647         hci_stack->adv_addr_type = packet[8];
2648     }
2649     if (IS_COMMAND(packet, hci_le_set_random_address)){
2650         bt_flip_addr(hci_stack->adv_address, &packet[3]);
2651     }
2652     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
2653         hci_stack->le_advertisements_active = packet[3];
2654     }
2655     if (IS_COMMAND(packet, hci_le_create_connection)){
2656         // white list used?
2657         uint8_t initiator_filter_policy = packet[7];
2658         switch (initiator_filter_policy){
2659             case 0:
2660                 // whitelist not used
2661                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
2662                 break;
2663             case 1:
2664                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
2665                 break;
2666             default:
2667                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
2668                 break;
2669         }
2670     }
2671     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
2672         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2673     }
2674 #endif
2675 
2676     hci_stack->num_cmd_packets--;
2677 
2678     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2679     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2680 
2681     // release packet buffer for synchronous transport implementations
2682     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
2683         hci_stack->hci_packet_buffer_reserved = 0;
2684     }
2685 
2686     return err;
2687 }
2688 
2689 // disconnect because of security block
2690 void hci_disconnect_security_block(hci_con_handle_t con_handle){
2691     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2692     if (!connection) return;
2693     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2694 }
2695 
2696 
2697 // Configure Secure Simple Pairing
2698 
2699 // enable will enable SSP during init
2700 void hci_ssp_set_enable(int enable){
2701     hci_stack->ssp_enable = enable;
2702 }
2703 
2704 int hci_local_ssp_activated(void){
2705     return hci_ssp_supported() && hci_stack->ssp_enable;
2706 }
2707 
2708 // if set, BTstack will respond to io capability request using authentication requirement
2709 void hci_ssp_set_io_capability(int io_capability){
2710     hci_stack->ssp_io_capability = io_capability;
2711 }
2712 void hci_ssp_set_authentication_requirement(int authentication_requirement){
2713     hci_stack->ssp_authentication_requirement = authentication_requirement;
2714 }
2715 
2716 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
2717 void hci_ssp_set_auto_accept(int auto_accept){
2718     hci_stack->ssp_auto_accept = auto_accept;
2719 }
2720 
2721 /**
2722  * pre: numcmds >= 0 - it's allowed to send a command to the controller
2723  */
2724 int hci_send_cmd(const hci_cmd_t *cmd, ...){
2725 
2726     if (!hci_can_send_command_packet_now()){
2727         log_error("hci_send_cmd called but cannot send packet now");
2728         return 0;
2729     }
2730 
2731     // for HCI INITIALIZATION
2732     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
2733     hci_stack->last_cmd_opcode = cmd->opcode;
2734 
2735     hci_reserve_packet_buffer();
2736     uint8_t * packet = hci_stack->hci_packet_buffer;
2737 
2738     va_list argptr;
2739     va_start(argptr, cmd);
2740     uint16_t size = hci_create_cmd_internal(packet, cmd, argptr);
2741     va_end(argptr);
2742 
2743     return hci_send_cmd_packet(packet, size);
2744 }
2745 
2746 // Create various non-HCI events.
2747 // TODO: generalize, use table similar to hci_create_command
2748 
2749 void hci_emit_state(void){
2750     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
2751     uint8_t event[3];
2752     event[0] = BTSTACK_EVENT_STATE;
2753     event[1] = sizeof(event) - 2;
2754     event[2] = hci_stack->state;
2755     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2756     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2757 }
2758 
2759 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
2760     uint8_t event[13];
2761     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
2762     event[1] = sizeof(event) - 2;
2763     event[2] = status;
2764     bt_store_16(event, 3, conn->con_handle);
2765     bt_flip_addr(&event[5], conn->address);
2766     event[11] = 1; // ACL connection
2767     event[12] = 0; // encryption disabled
2768     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
2769     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2770 }
2771 
2772 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, uint16_t conn_handle, uint8_t status){
2773     uint8_t event[21];
2774     event[0] = HCI_EVENT_LE_META;
2775     event[1] = sizeof(event) - 2;
2776     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
2777     event[3] = status;
2778     bt_store_16(event, 4, conn_handle);
2779     event[6] = 0; // TODO: role
2780     event[7] = address_type;
2781     bt_flip_addr(&event[8], address);
2782     bt_store_16(event, 14, 0); // interval
2783     bt_store_16(event, 16, 0); // latency
2784     bt_store_16(event, 18, 0); // supervision timeout
2785     event[20] = 0; // master clock accuracy
2786     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
2787     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2788 }
2789 
2790 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
2791     uint8_t event[6];
2792     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
2793     event[1] = sizeof(event) - 2;
2794     event[2] = 0; // status = OK
2795     bt_store_16(event, 3, handle);
2796     event[5] = reason;
2797     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
2798     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2799 }
2800 
2801 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
2802     if (disable_l2cap_timeouts) return;
2803     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
2804     uint8_t event[4];
2805     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
2806     event[1] = sizeof(event) - 2;
2807     bt_store_16(event, 2, conn->con_handle);
2808     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
2809     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2810 }
2811 
2812 void hci_emit_nr_connections_changed(void){
2813     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
2814     uint8_t event[3];
2815     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
2816     event[1] = sizeof(event) - 2;
2817     event[2] = nr_hci_connections();
2818     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2819     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2820 }
2821 
2822 void hci_emit_hci_open_failed(void){
2823     log_info("BTSTACK_EVENT_POWERON_FAILED");
2824     uint8_t event[2];
2825     event[0] = BTSTACK_EVENT_POWERON_FAILED;
2826     event[1] = sizeof(event) - 2;
2827     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2828     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2829 }
2830 
2831 #ifndef EMBEDDED
2832 void hci_emit_btstack_version(void){
2833     log_info("BTSTACK_EVENT_VERSION %u.%u", BTSTACK_MAJOR, BTSTACK_MINOR);
2834     uint8_t event[6];
2835     event[0] = BTSTACK_EVENT_VERSION;
2836     event[1] = sizeof(event) - 2;
2837     event[2] = BTSTACK_MAJOR;
2838     event[3] = BTSTACK_MINOR;
2839     bt_store_16(event, 4, 3257);    // last SVN commit on Google Code + 1
2840     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2841     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2842 }
2843 #endif
2844 
2845 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
2846     log_info("BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED %u", enabled);
2847     uint8_t event[3];
2848     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
2849     event[1] = sizeof(event) - 2;
2850     event[2] = enabled;
2851     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2852     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2853 }
2854 
2855 void hci_emit_remote_name_cached(bd_addr_t addr, device_name_t *name){
2856     uint8_t event[2+1+6+248+1]; // +1 for \0 in log_info
2857     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
2858     event[1] = sizeof(event) - 2 - 1;
2859     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
2860     bt_flip_addr(&event[3], addr);
2861     memcpy(&event[9], name, 248);
2862 
2863     event[9+248] = 0;   // assert \0 for log_info
2864     log_info("BTSTACK_EVENT_REMOTE_NAME_CACHED %s = '%s'", bd_addr_to_str(addr), &event[9]);
2865 
2866     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)-1);
2867     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event)-1);
2868 }
2869 
2870 void hci_emit_discoverable_enabled(uint8_t enabled){
2871     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
2872     uint8_t event[3];
2873     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
2874     event[1] = sizeof(event) - 2;
2875     event[2] = enabled;
2876     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2877     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2878 }
2879 
2880 void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
2881     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
2882     uint8_t event[5];
2883     int pos = 0;
2884     event[pos++] = GAP_SECURITY_LEVEL;
2885     event[pos++] = sizeof(event) - 2;
2886     bt_store_16(event, 2, con_handle);
2887     pos += 2;
2888     event[pos++] = level;
2889     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2890     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2891 }
2892 
2893 void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
2894     log_info("hci_emit_dedicated_bonding_result %u ", status);
2895     uint8_t event[9];
2896     int pos = 0;
2897     event[pos++] = GAP_DEDICATED_BONDING_COMPLETED;
2898     event[pos++] = sizeof(event) - 2;
2899     event[pos++] = status;
2900     bt_flip_addr( &event[pos], address);
2901     pos += 6;
2902     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2903     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2904 }
2905 
2906 // query if remote side supports eSCO
2907 int hci_remote_eSCO_supported(hci_con_handle_t con_handle){
2908     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2909     if (!connection) return 0;
2910     return connection->remote_supported_feature_eSCO;
2911 }
2912 
2913 // query if remote side supports SSP
2914 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
2915     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2916     if (!connection) return 0;
2917     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
2918 }
2919 
2920 int hci_ssp_supported_on_both_sides(hci_con_handle_t handle){
2921     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
2922 }
2923 
2924 // GAP API
2925 /**
2926  * @bbrief enable/disable bonding. default is enabled
2927  * @praram enabled
2928  */
2929 void gap_set_bondable_mode(int enable){
2930     hci_stack->bondable = enable ? 1 : 0;
2931 }
2932 /**
2933  * @brief Get bondable mode.
2934  * @return 1 if bondable
2935  */
2936 int gap_get_bondable_mode(void){
2937     return hci_stack->bondable;
2938 }
2939 
2940 /**
2941  * @brief map link keys to security levels
2942  */
2943 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
2944     switch (link_key_type){
2945         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
2946             return LEVEL_4;
2947         case COMBINATION_KEY:
2948         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
2949             return LEVEL_3;
2950         default:
2951             return LEVEL_2;
2952     }
2953 }
2954 
2955 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
2956     if (!connection) return LEVEL_0;
2957     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
2958     return gap_security_level_for_link_key_type(connection->link_key_type);
2959 }
2960 
2961 
2962 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
2963     log_info("gap_mitm_protection_required_for_security_level %u", level);
2964     return level > LEVEL_2;
2965 }
2966 
2967 /**
2968  * @brief get current security level
2969  */
2970 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
2971     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2972     if (!connection) return LEVEL_0;
2973     return gap_security_level_for_connection(connection);
2974 }
2975 
2976 /**
2977  * @brief request connection to device to
2978  * @result GAP_AUTHENTICATION_RESULT
2979  */
2980 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
2981     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2982     if (!connection){
2983         hci_emit_security_level(con_handle, LEVEL_0);
2984         return;
2985     }
2986     gap_security_level_t current_level = gap_security_level(con_handle);
2987     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
2988     if (current_level >= requested_level){
2989         hci_emit_security_level(con_handle, current_level);
2990         return;
2991     }
2992 
2993     connection->requested_security_level = requested_level;
2994 
2995 #if 0
2996     // sending encryption request without a link key results in an error.
2997     // TODO: figure out how to use it properly
2998 
2999     // would enabling ecnryption suffice (>= LEVEL_2)?
3000     if (hci_stack->remote_device_db){
3001         link_key_type_t link_key_type;
3002         link_key_t      link_key;
3003         if (hci_stack->remote_device_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3004             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3005                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3006                 return;
3007             }
3008         }
3009     }
3010 #endif
3011 
3012     // try to authenticate connection
3013     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3014     hci_run();
3015 }
3016 
3017 /**
3018  * @brief start dedicated bonding with device. disconnect after bonding
3019  * @param device
3020  * @param request MITM protection
3021  * @result GAP_DEDICATED_BONDING_COMPLETE
3022  */
3023 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3024 
3025     // create connection state machine
3026     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3027 
3028     if (!connection){
3029         return BTSTACK_MEMORY_ALLOC_FAILED;
3030     }
3031 
3032     // delete linkn key
3033     hci_drop_link_key_for_bd_addr(device);
3034 
3035     // configure LEVEL_2/3, dedicated bonding
3036     connection->state = SEND_CREATE_CONNECTION;
3037     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3038     log_info("gap_dedicated_bonding, mitm %u -> level %u", mitm_protection_required, connection->requested_security_level);
3039     connection->bonding_flags = BONDING_DEDICATED;
3040 
3041     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3042 
3043     // handle: connnection failure (connection complete != ok)
3044     // handle: authentication failure
3045     // handle: disconnect on done
3046 
3047     hci_run();
3048 
3049     return 0;
3050 }
3051 
3052 void gap_set_local_name(const char * local_name){
3053     hci_stack->local_name = local_name;
3054 }
3055 
3056 uint8_t le_central_start_scan(void){
3057     if (hci_stack->le_scanning_state == LE_SCANNING) return 0;
3058     hci_stack->le_scanning_state = LE_START_SCAN;
3059     hci_run();
3060     return 0;
3061 }
3062 
3063 uint8_t le_central_stop_scan(void){
3064     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return 0;
3065     hci_stack->le_scanning_state = LE_STOP_SCAN;
3066     hci_run();
3067     return 0;
3068 }
3069 
3070 void le_central_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3071     hci_stack->le_scan_type     = scan_type;
3072     hci_stack->le_scan_interval = scan_interval;
3073     hci_stack->le_scan_window   = scan_window;
3074     hci_run();
3075 }
3076 
3077 uint8_t le_central_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3078     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3079     if (!conn){
3080         log_info("le_central_connect: no connection exists yet, creating context");
3081         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3082         if (!conn){
3083             // notify client that alloc failed
3084             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3085             log_info("le_central_connect: failed to alloc hci_connection_t");
3086             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3087         }
3088         conn->state = SEND_CREATE_CONNECTION;
3089         log_info("le_central_connect: send create connection next");
3090         hci_run();
3091         return 0;
3092     }
3093 
3094     if (!hci_is_le_connection(conn) ||
3095         conn->state == SEND_CREATE_CONNECTION ||
3096         conn->state == SENT_CREATE_CONNECTION) {
3097         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3098         log_error("le_central_connect: classic connection or connect is already being created");
3099         return GATT_CLIENT_IN_WRONG_STATE;
3100     }
3101 
3102     log_info("le_central_connect: context exists with state %u", conn->state);
3103     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3104     hci_run();
3105     return 0;
3106 }
3107 
3108 // @assumption: only a single outgoing LE Connection exists
3109 static hci_connection_t * le_central_get_outgoing_connection(void){
3110     linked_item_t *it;
3111     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
3112         hci_connection_t * conn = (hci_connection_t *) it;
3113         if (!hci_is_le_connection(conn)) continue;
3114         switch (conn->state){
3115             case SEND_CREATE_CONNECTION:
3116             case SENT_CREATE_CONNECTION:
3117                 return conn;
3118             default:
3119                 break;
3120         };
3121     }
3122     return NULL;
3123 }
3124 
3125 uint8_t le_central_connect_cancel(void){
3126     hci_connection_t * conn = le_central_get_outgoing_connection();
3127     if (!conn) return 0;
3128     switch (conn->state){
3129         case SEND_CREATE_CONNECTION:
3130             // skip sending create connection and emit event instead
3131             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3132             linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
3133             btstack_memory_hci_connection_free( conn );
3134             break;
3135         case SENT_CREATE_CONNECTION:
3136             // request to send cancel connection
3137             conn->state = SEND_CANCEL_CONNECTION;
3138             hci_run();
3139             break;
3140         default:
3141             break;
3142     }
3143     return 0;
3144 }
3145 
3146 /**
3147  * @brief Updates the connection parameters for a given LE connection
3148  * @param handle
3149  * @param conn_interval_min (unit: 1.25ms)
3150  * @param conn_interval_max (unit: 1.25ms)
3151  * @param conn_latency
3152  * @param supervision_timeout (unit: 10ms)
3153  * @returns 0 if ok
3154  */
3155 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3156     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3157     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3158     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3159     connection->le_conn_interval_min = conn_interval_min;
3160     connection->le_conn_interval_max = conn_interval_max;
3161     connection->le_conn_latency = conn_latency;
3162     connection->le_supervision_timeout = supervision_timeout;
3163     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3164     hci_run();
3165     return 0;
3166 }
3167 
3168 /**
3169  * @brief Request an update of the connection parameter for a given LE connection
3170  * @param handle
3171  * @param conn_interval_min (unit: 1.25ms)
3172  * @param conn_interval_max (unit: 1.25ms)
3173  * @param conn_latency
3174  * @param supervision_timeout (unit: 10ms)
3175  * @returns 0 if ok
3176  */
3177 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3178     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3179     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3180     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3181     connection->le_conn_interval_min = conn_interval_min;
3182     connection->le_conn_interval_max = conn_interval_max;
3183     connection->le_conn_latency = conn_latency;
3184     connection->le_supervision_timeout = supervision_timeout;
3185     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3186     hci_run();
3187     return 0;
3188 }
3189 
3190 /**
3191  * @brief Set Advertisement Data
3192  * @param advertising_data_length
3193  * @param advertising_data (max 31 octets)
3194  * @note data is not copied, pointer has to stay valid
3195  */
3196 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3197     hci_stack->le_advertisements_data_len = advertising_data_length;
3198     hci_stack->le_advertisements_data = advertising_data;
3199     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_DATA;
3200     // disable advertisements before setting data
3201     if (hci_stack->le_advertisements_active){
3202         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3203     }
3204     hci_run();
3205 }
3206 
3207 /**
3208  * @brief Set Advertisement Parameters
3209  * @param adv_int_min
3210  * @param adv_int_max
3211  * @param adv_type
3212  * @param own_address_type
3213  * @param direct_address_type
3214  * @param direct_address
3215  * @param channel_map
3216  * @param filter_policy
3217  *
3218  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3219  */
3220  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3221     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3222     uint8_t channel_map, uint8_t filter_policy) {
3223 
3224     hci_stack->le_advertisements_interval_min = adv_int_min;
3225     hci_stack->le_advertisements_interval_max = adv_int_max;
3226     hci_stack->le_advertisements_type = adv_type;
3227     hci_stack->le_advertisements_own_address_type = own_address_type;
3228     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3229     hci_stack->le_advertisements_channel_map = channel_map;
3230     hci_stack->le_advertisements_filter_policy = filter_policy;
3231     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3232 
3233     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3234     // disable advertisements before changing params
3235     if (hci_stack->le_advertisements_active){
3236         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3237     }
3238     hci_run();
3239  }
3240 
3241 /**
3242  * @brief Enable/Disable Advertisements
3243  * @param enabled
3244  */
3245 void gap_advertisements_enable(int enabled){
3246     hci_stack->le_advertisements_enabled = enabled;
3247     if (enabled && !hci_stack->le_advertisements_active){
3248         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3249     }
3250     if (!enabled && hci_stack->le_advertisements_active){
3251         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3252     }
3253     hci_run();
3254 }
3255 
3256 
3257 uint8_t gap_disconnect(hci_con_handle_t handle){
3258     hci_connection_t * conn = hci_connection_for_handle(handle);
3259     if (!conn){
3260         hci_emit_disconnection_complete(handle, 0);
3261         return 0;
3262     }
3263     conn->state = SEND_DISCONNECT;
3264     hci_run();
3265     return 0;
3266 }
3267 
3268 /**
3269  * @brief Get connection type
3270  * @param con_handle
3271  * @result connection_type
3272  */
3273 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3274     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3275     if (!conn) return GAP_CONNECTION_INVALID;
3276     switch (conn->address_type){
3277         case BD_ADDR_TYPE_LE_PUBLIC:
3278         case BD_ADDR_TYPE_LE_RANDOM:
3279             return GAP_CONNECTION_LE;
3280         case BD_ADDR_TYPE_SCO:
3281             return GAP_CONNECTION_SCO;
3282         case BD_ADDR_TYPE_CLASSIC:
3283             return GAP_CONNECTION_ACL;
3284         default:
3285             return GAP_CONNECTION_INVALID;
3286     }
3287 }
3288 
3289 #ifdef HAVE_BLE
3290 
3291 /**
3292  * @brief Auto Connection Establishment - Start Connecting to device
3293  * @param address_typ
3294  * @param address
3295  * @returns 0 if ok
3296  */
3297 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3298     // check capacity
3299     int num_entries = linked_list_count(&hci_stack->le_whitelist);
3300     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3301     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3302     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3303     entry->address_type = address_type;
3304     memcpy(entry->address, address, 6);
3305     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3306     linked_list_add(&hci_stack->le_whitelist, (linked_item_t*) entry);
3307     hci_run();
3308     return 0;
3309 }
3310 
3311 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3312     linked_list_iterator_t it;
3313     linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3314     while (linked_list_iterator_has_next(&it)){
3315         whitelist_entry_t * entry = (whitelist_entry_t*) linked_list_iterator_next(&it);
3316         if (entry->address_type != address_type) continue;
3317         if (memcmp(entry->address, address, 6) != 0) continue;
3318         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3319             // remove from controller if already present
3320             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3321             continue;
3322         }
3323         // direclty remove entry from whitelist
3324         linked_list_iterator_remove(&it);
3325         btstack_memory_whitelist_entry_free(entry);
3326     }
3327 }
3328 
3329 /**
3330  * @brief Auto Connection Establishment - Stop Connecting to device
3331  * @param address_typ
3332  * @param address
3333  * @returns 0 if ok
3334  */
3335 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3336     hci_remove_from_whitelist(address_type, address);
3337     hci_run();
3338     return 0;
3339 }
3340 
3341 /**
3342  * @brief Auto Connection Establishment - Stop everything
3343  * @note  Convenience function to stop all active auto connection attempts
3344  */
3345 void gap_auto_connection_stop_all(void){
3346     linked_list_iterator_t it;
3347     linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3348     while (linked_list_iterator_has_next(&it)){
3349         whitelist_entry_t * entry = (whitelist_entry_t*) linked_list_iterator_next(&it);
3350         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3351             // remove from controller if already present
3352             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3353             continue;
3354         }
3355         // directly remove entry from whitelist
3356         linked_list_iterator_remove(&it);
3357         btstack_memory_whitelist_entry_free(entry);
3358     }
3359     hci_run();
3360 }
3361 
3362 #endif
3363 
3364 /**
3365  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3366  */
3367 void hci_set_sco_voice_setting(uint16_t voice_setting){
3368     hci_stack->sco_voice_setting = voice_setting;
3369 }
3370 
3371 /**
3372  * @brief Get SCO Voice Setting
3373  * @return current voice setting
3374  */
3375 uint16_t hci_get_sco_voice_setting(){
3376     return hci_stack->sco_voice_setting;
3377 }
3378 
3379 /**
3380  * @brief Set callback for Bluetooth Hardware Error
3381  */
3382 void hci_set_hardware_error_callback(void (*fn)(void)){
3383     hci_stack->hardware_error_callback = fn;
3384 }
3385 
3386 
3387 void hci_disconnect_all(void){
3388     linked_list_iterator_t it;
3389     linked_list_iterator_init(&it, &hci_stack->connections);
3390     while (linked_list_iterator_has_next(&it)){
3391         hci_connection_t * con = (hci_connection_t*) linked_list_iterator_next(&it);
3392         if (con->state == SENT_DISCONNECT) continue;
3393         con->state = SEND_DISCONNECT;
3394     }
3395     hci_run();
3396 }
3397