xref: /btstack/src/hci.c (revision fac60fea7b1f8035236d9793b267925dfa9a010a)
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 
48 #ifdef HAVE_EMBEDDED_TICK
49 #include "btstack_run_loop_embedded.h"
50 #endif
51 
52 #ifdef HAVE_PLATFORM_IPHONE_OS
53 #include "../port/ios/src/btstack_control_iphone.h"
54 #endif
55 
56 #ifdef ENABLE_BLE
57 #include "gap.h"
58 #endif
59 
60 #include <stdarg.h>
61 #include <string.h>
62 #include <stdio.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "gap.h"
70 #include "hci.h"
71 #include "hci_cmd.h"
72 #include "hci_dump.h"
73 
74 
75 #define HCI_CONNECTION_TIMEOUT_MS 10000
76 #define HCI_RESET_RESEND_TIMEOUT_MS 200
77 
78 // prototypes
79 static void hci_update_scan_enable(void);
80 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
81 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
82 static void hci_connection_timestamp(hci_connection_t *connection);
83 static int  hci_power_control_on(void);
84 static void hci_power_control_off(void);
85 static void hci_state_reset(void);
86 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
87 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
88 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
89 static void hci_emit_nr_connections_changed(void);
90 static void hci_emit_hci_open_failed(void);
91 static void hci_emit_discoverable_enabled(uint8_t enabled);
92 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
93 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
94 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
95 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
96 static void hci_notify_if_sco_can_send_now(void);
97 static void hci_run(void);
98 static int  hci_is_le_connection(hci_connection_t * connection);
99 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
100 static int  hci_local_ssp_activated(void);
101 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
102 
103 #ifdef ENABLE_BLE
104 // called from test/ble_client/advertising_data_parser.c
105 void le_handle_advertisement_report(uint8_t *packet, int size);
106 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
107 #endif
108 
109 // the STACK is here
110 #ifndef HAVE_MALLOC
111 static hci_stack_t   hci_stack_static;
112 #endif
113 static hci_stack_t * hci_stack = NULL;
114 
115 // test helper
116 static uint8_t disable_l2cap_timeouts = 0;
117 
118 /**
119  * create connection for given address
120  *
121  * @return connection OR NULL, if no memory left
122  */
123 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
124     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
125     hci_connection_t * conn = btstack_memory_hci_connection_get();
126     if (!conn) return NULL;
127     memset(conn, 0, sizeof(hci_connection_t));
128     bd_addr_copy(conn->address, addr);
129     conn->address_type = addr_type;
130     conn->con_handle = 0xffff;
131     conn->authentication_flags = AUTH_FLAGS_NONE;
132     conn->bonding_flags = 0;
133     conn->requested_security_level = LEVEL_0;
134     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
135     btstack_run_loop_set_timer_context(&conn->timeout, conn);
136     hci_connection_timestamp(conn);
137     conn->acl_recombination_length = 0;
138     conn->acl_recombination_pos = 0;
139     conn->num_acl_packets_sent = 0;
140     conn->num_sco_packets_sent = 0;
141     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
142     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
143     return conn;
144 }
145 
146 
147 /**
148  * get le connection parameter range
149 *
150  * @return le connection parameter range struct
151  */
152 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
153     *range = hci_stack->le_connection_parameter_range;
154 }
155 
156 /**
157  * set le connection parameter range
158  *
159  */
160 
161 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
162     hci_stack->le_connection_parameter_range = *range;
163 }
164 
165 /**
166  * get hci connections iterator
167  *
168  * @return hci connections iterator
169  */
170 
171 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
172     btstack_linked_list_iterator_init(it, &hci_stack->connections);
173 }
174 
175 /**
176  * get connection for a given handle
177  *
178  * @return connection OR NULL, if not found
179  */
180 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
181     btstack_linked_list_iterator_t it;
182     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
183     while (btstack_linked_list_iterator_has_next(&it)){
184         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
185         if ( item->con_handle == con_handle ) {
186             return item;
187         }
188     }
189     return NULL;
190 }
191 
192 /**
193  * get connection for given address
194  *
195  * @return connection OR NULL, if not found
196  */
197 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
198     btstack_linked_list_iterator_t it;
199     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
200     while (btstack_linked_list_iterator_has_next(&it)){
201         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
202         if (connection->address_type != addr_type)  continue;
203         if (memcmp(addr, connection->address, 6) != 0) continue;
204         return connection;
205     }
206     return NULL;
207 }
208 
209 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
210     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
211 #ifdef HAVE_EMBEDDED_TICK
212     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
213         // connections might be timed out
214         hci_emit_l2cap_check_timeout(connection);
215     }
216 #else
217     if (btstack_run_loop_get_time_ms() > connection->timestamp + HCI_CONNECTION_TIMEOUT_MS){
218         // connections might be timed out
219         hci_emit_l2cap_check_timeout(connection);
220     }
221 #endif
222 }
223 
224 static void hci_connection_timestamp(hci_connection_t *connection){
225 #ifdef HAVE_EMBEDDED_TICK
226     connection->timestamp = btstack_run_loop_embedded_get_ticks();
227 #else
228     connection->timestamp = btstack_run_loop_get_time_ms();
229 #endif
230 }
231 
232 
233 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
234     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
235 }
236 
237 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
238     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
239 }
240 
241 
242 /**
243  * add authentication flags and reset timer
244  * @note: assumes classic connection
245  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
246  */
247 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
248     bd_addr_t addr;
249     reverse_bd_addr(bd_addr, addr);
250     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
251     if (conn) {
252         connectionSetAuthenticationFlags(conn, flags);
253         hci_connection_timestamp(conn);
254     }
255 }
256 
257 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
258     hci_connection_t * conn = hci_connection_for_handle(handle);
259     if (!conn) return 0;
260     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
261     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
262     return 0;
263 }
264 
265 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
266     if (!hci_stack->link_key_db) return;
267     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
268     hci_stack->link_key_db->delete_link_key(addr);
269 }
270 
271 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
272     if (!hci_stack->link_key_db) return;
273     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
274     hci_stack->link_key_db->put_link_key(addr, link_key, type);
275 }
276 
277 static int hci_is_le_connection(hci_connection_t * connection){
278     return  connection->address_type == BD_ADDR_TYPE_LE_PUBLIC ||
279     connection->address_type == BD_ADDR_TYPE_LE_RANDOM;
280 }
281 
282 /**
283  * count connections
284  */
285 static int nr_hci_connections(void){
286     int count = 0;
287     btstack_linked_item_t *it;
288     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
289     return count;
290 }
291 
292 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
293 
294     int num_packets_sent_classic = 0;
295     int num_packets_sent_le = 0;
296 
297     btstack_linked_item_t *it;
298     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
299         hci_connection_t * connection = (hci_connection_t *) it;
300         if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
301             num_packets_sent_classic += connection->num_acl_packets_sent;
302         } else {
303             num_packets_sent_le += connection->num_acl_packets_sent;
304         }
305     }
306     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
307     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
308     int free_slots_le = 0;
309 
310     if (free_slots_classic < 0){
311         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);
312         return 0;
313     }
314 
315     if (hci_stack->le_acl_packets_total_num){
316         // if we have LE slots, they are used
317         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
318         if (free_slots_le < 0){
319             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);
320             return 0;
321         }
322     } else {
323         // otherwise, classic slots are used for LE, too
324         free_slots_classic -= num_packets_sent_le;
325         if (free_slots_classic < 0){
326             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);
327             return 0;
328         }
329     }
330 
331     switch (address_type){
332         case BD_ADDR_TYPE_UNKNOWN:
333             log_error("hci_number_free_acl_slots: unknown address type");
334             return 0;
335 
336         case BD_ADDR_TYPE_CLASSIC:
337             return free_slots_classic;
338 
339         default:
340            if (hci_stack->le_acl_packets_total_num){
341                return free_slots_le;
342            }
343            return free_slots_classic;
344     }
345 }
346 
347 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
348     // get connection type
349     hci_connection_t * connection = hci_connection_for_handle(con_handle);
350     if (!connection){
351         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
352         return 0;
353     }
354     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
355 }
356 
357 static int hci_number_free_sco_slots(void){
358     int num_sco_packets_sent = 0;
359     btstack_linked_item_t *it;
360     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
361         hci_connection_t * connection = (hci_connection_t *) it;
362         num_sco_packets_sent += connection->num_sco_packets_sent;
363     }
364     if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
365         log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
366         return 0;
367     }
368     // log_info("hci_number_free_sco_slots u", handle, num_sco_packets_sent);
369     return hci_stack->sco_packets_total_num - num_sco_packets_sent;
370 }
371 
372 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
373 int hci_can_send_command_packet_now(void){
374     if (hci_stack->hci_packet_buffer_reserved) return 0;
375 
376     // check for async hci transport implementations
377     if (hci_stack->hci_transport->can_send_packet_now){
378         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
379             return 0;
380         }
381     }
382 
383     return hci_stack->num_cmd_packets > 0;
384 }
385 
386 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
387     // check for async hci transport implementations
388     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
389     return hci_stack->hci_transport->can_send_packet_now(packet_type);
390 }
391 
392 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
393     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
394     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
395 }
396 
397 int hci_can_send_acl_classic_packet_now(void){
398     if (hci_stack->hci_packet_buffer_reserved) return 0;
399     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_CLASSIC);
400 }
401 
402 int hci_can_send_acl_le_packet_now(void){
403     if (hci_stack->hci_packet_buffer_reserved) return 0;
404     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
405 }
406 
407 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
408     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
409     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
410 }
411 
412 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
413     if (hci_stack->hci_packet_buffer_reserved) return 0;
414     return hci_can_send_prepared_acl_packet_now(con_handle);
415 }
416 
417 int hci_can_send_prepared_sco_packet_now(void){
418     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
419     if (!hci_stack->synchronous_flow_control_enabled) return 1;
420     return hci_number_free_sco_slots() > 0;
421 }
422 
423 int hci_can_send_sco_packet_now(void){
424     if (hci_stack->hci_packet_buffer_reserved) return 0;
425     return hci_can_send_prepared_sco_packet_now();
426 }
427 
428 void hci_request_sco_can_send_now_event(void){
429     hci_stack->sco_waiting_for_can_send_now = 1;
430     hci_notify_if_sco_can_send_now();
431 }
432 
433 // used for internal checks in l2cap.c
434 int hci_is_packet_buffer_reserved(void){
435     return hci_stack->hci_packet_buffer_reserved;
436 }
437 
438 // reserves outgoing packet buffer. @returns 1 if successful
439 int hci_reserve_packet_buffer(void){
440     if (hci_stack->hci_packet_buffer_reserved) {
441         log_error("hci_reserve_packet_buffer called but buffer already reserved");
442         return 0;
443     }
444     hci_stack->hci_packet_buffer_reserved = 1;
445     return 1;
446 }
447 
448 void hci_release_packet_buffer(void){
449     hci_stack->hci_packet_buffer_reserved = 0;
450 }
451 
452 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
453 static int hci_transport_synchronous(void){
454     return hci_stack->hci_transport->can_send_packet_now == NULL;
455 }
456 
457 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
458 
459     // 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);
460 
461     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
462     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
463     if (hci_is_le_connection(connection) && hci_stack->le_data_packets_length > 0){
464         max_acl_data_packet_length = hci_stack->le_data_packets_length;
465     }
466 
467     // testing: reduce buffer to minimum
468     // max_acl_data_packet_length = 52;
469 
470     log_debug("hci_send_acl_packet_fragments entered");
471 
472     int err;
473     // multiple packets could be send on a synchronous HCI transport
474     while (1){
475 
476         log_debug("hci_send_acl_packet_fragments loop entered");
477 
478         // get current data
479         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
480         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
481         int more_fragments = 0;
482 
483         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
484         if (current_acl_data_packet_length > max_acl_data_packet_length){
485             more_fragments = 1;
486             current_acl_data_packet_length = max_acl_data_packet_length;
487         }
488 
489         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
490         if (acl_header_pos > 0){
491             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
492             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
493             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
494         }
495 
496         // update header len
497         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
498 
499         // count packet
500         connection->num_acl_packets_sent++;
501         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %u)", more_fragments);
502 
503         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
504         if (more_fragments){
505             // update start of next fragment to send
506             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
507         } else {
508             // done
509             hci_stack->acl_fragmentation_pos = 0;
510             hci_stack->acl_fragmentation_total_size = 0;
511         }
512 
513         // send packet
514         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
515         const int size = current_acl_data_packet_length + 4;
516         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
517         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
518 
519         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %u)", more_fragments);
520 
521         // done yet?
522         if (!more_fragments) break;
523 
524         // can send more?
525         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
526     }
527 
528     log_debug("hci_send_acl_packet_fragments loop over");
529 
530     // release buffer now for synchronous transport
531     if (hci_transport_synchronous()){
532         hci_release_packet_buffer();
533         // notify upper stack that it might be possible to send again
534         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
535         hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
536     }
537 
538     return err;
539 }
540 
541 // pre: caller has reserved the packet buffer
542 int hci_send_acl_packet_buffer(int size){
543 
544     // log_info("hci_send_acl_packet_buffer size %u", size);
545 
546     if (!hci_stack->hci_packet_buffer_reserved) {
547         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
548         return 0;
549     }
550 
551     uint8_t * packet = hci_stack->hci_packet_buffer;
552     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
553 
554     // check for free places on Bluetooth module
555     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
556         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
557         hci_release_packet_buffer();
558         return BTSTACK_ACL_BUFFERS_FULL;
559     }
560 
561     hci_connection_t *connection = hci_connection_for_handle( con_handle);
562     if (!connection) {
563         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
564         hci_release_packet_buffer();
565         return 0;
566     }
567     hci_connection_timestamp(connection);
568 
569     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
570 
571     // setup data
572     hci_stack->acl_fragmentation_total_size = size;
573     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
574 
575     return hci_send_acl_packet_fragments(connection);
576 }
577 
578 // pre: caller has reserved the packet buffer
579 int hci_send_sco_packet_buffer(int size){
580 
581     // log_info("hci_send_acl_packet_buffer size %u", size);
582 
583     if (!hci_stack->hci_packet_buffer_reserved) {
584         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
585         return 0;
586     }
587 
588     uint8_t * packet = hci_stack->hci_packet_buffer;
589 
590     // skip checks in loopback mode
591     if (!hci_stack->loopback_mode){
592         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
593 
594         // check for free places on Bluetooth module
595         if (!hci_can_send_prepared_sco_packet_now()) {
596             log_error("hci_send_sco_packet_buffer called but no free ACL buffers on controller");
597             hci_release_packet_buffer();
598             return BTSTACK_ACL_BUFFERS_FULL;
599         }
600 
601         // track send packet in connection struct
602         hci_connection_t *connection = hci_connection_for_handle( con_handle);
603         if (!connection) {
604             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
605             hci_release_packet_buffer();
606             return 0;
607         }
608         connection->num_sco_packets_sent++;
609     }
610 
611     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
612     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
613 
614     if (hci_transport_synchronous()){
615         hci_release_packet_buffer();
616         // notify upper stack that it might be possible to send again
617         uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
618         hci_emit_event(&event[0], sizeof(event), 0);    // don't dump
619     }
620 
621     return err;
622 }
623 
624 static void acl_handler(uint8_t *packet, int size){
625 
626     // log_info("acl_handler: size %u", size);
627 
628     // get info
629     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
630     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
631     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
632     uint16_t acl_length         = READ_ACL_LENGTH(packet);
633 
634     // ignore non-registered handle
635     if (!conn){
636         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
637         return;
638     }
639 
640     // assert packet is complete
641     if (acl_length + 4 != size){
642         log_error("hci.c: acl_handler called with ACL packet of wrong size %u, expected %u => dropping packet", size, acl_length + 4);
643         return;
644     }
645 
646     // update idle timestamp
647     hci_connection_timestamp(conn);
648 
649     // handle different packet types
650     switch (acl_flags & 0x03) {
651 
652         case 0x01: // continuation fragment
653 
654             // sanity checks
655             if (conn->acl_recombination_pos == 0) {
656                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
657                 return;
658             }
659             if (conn->acl_recombination_pos + acl_length > 4 + HCI_ACL_BUFFER_SIZE){
660                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
661                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
662                 conn->acl_recombination_pos = 0;
663                 return;
664             }
665 
666             // append fragment payload (header already stored)
667             memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos], &packet[4], acl_length );
668             conn->acl_recombination_pos += acl_length;
669 
670             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
671             //        conn->acl_recombination_pos, conn->acl_recombination_length);
672 
673             // forward complete L2CAP packet if complete.
674             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
675                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
676                 // reset recombination buffer
677                 conn->acl_recombination_length = 0;
678                 conn->acl_recombination_pos = 0;
679             }
680             break;
681 
682         case 0x02: { // first fragment
683 
684             // sanity check
685             if (conn->acl_recombination_pos) {
686                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
687                 conn->acl_recombination_pos = 0;
688             }
689 
690             // peek into L2CAP packet!
691             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
692 
693             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
694 
695             // compare fragment size to L2CAP packet size
696             if (acl_length >= l2cap_length + 4){
697                 // forward fragment as L2CAP packet
698                 hci_emit_acl_packet(packet, acl_length + 4);
699             } else {
700 
701                 if (acl_length > HCI_ACL_BUFFER_SIZE){
702                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
703                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
704                     return;
705                 }
706 
707                 // store first fragment and tweak acl length for complete package
708                 memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], packet, acl_length + 4);
709                 conn->acl_recombination_pos    = acl_length + 4;
710                 conn->acl_recombination_length = l2cap_length;
711                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
712             }
713             break;
714 
715         }
716         default:
717             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
718             return;
719     }
720 
721     // execute main loop
722     hci_run();
723 }
724 
725 static void hci_shutdown_connection(hci_connection_t *conn){
726     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
727 
728     btstack_run_loop_remove_timer(&conn->timeout);
729 
730     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
731     btstack_memory_hci_connection_free( conn );
732 
733     // now it's gone
734     hci_emit_nr_connections_changed();
735 }
736 
737 static const uint16_t packet_type_sizes[] = {
738     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
739     HCI_ACL_DH1_SIZE, 0, 0, 0,
740     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
741     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
742 };
743 static const uint8_t  packet_type_feature_requirement_bit[] = {
744      0, // 3 slot packets
745      1, // 5 slot packets
746     25, // EDR 2 mpbs
747     26, // EDR 3 mbps
748     39, // 3 slot EDR packts
749     40, // 5 slot EDR packet
750 };
751 static const uint16_t packet_type_feature_packet_mask[] = {
752     0x0f00, // 3 slot packets
753     0xf000, // 5 slot packets
754     0x1102, // EDR 2 mpbs
755     0x2204, // EDR 3 mbps
756     0x0300, // 3 slot EDR packts
757     0x3000, // 5 slot EDR packet
758 };
759 
760 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
761     // enable packet types based on size
762     uint16_t packet_types = 0;
763     unsigned int i;
764     for (i=0;i<16;i++){
765         if (packet_type_sizes[i] == 0) continue;
766         if (packet_type_sizes[i] <= buffer_size){
767             packet_types |= 1 << i;
768         }
769     }
770     // disable packet types due to missing local supported features
771     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
772         int bit_idx = packet_type_feature_requirement_bit[i];
773         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
774         if (feature_set) continue;
775         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
776         packet_types &= ~packet_type_feature_packet_mask[i];
777     }
778     // flip bits for "may not be used"
779     packet_types ^= 0x3306;
780     return packet_types;
781 }
782 
783 uint16_t hci_usable_acl_packet_types(void){
784     return hci_stack->packet_types;
785 }
786 
787 uint8_t* hci_get_outgoing_packet_buffer(void){
788     // hci packet buffer is >= acl data packet length
789     return hci_stack->hci_packet_buffer;
790 }
791 
792 uint16_t hci_max_acl_data_packet_length(void){
793     return hci_stack->acl_data_packet_length;
794 }
795 
796 int hci_extended_sco_link_supported(void){
797     // No. 31, byte 3, bit 7
798     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
799 }
800 
801 int hci_non_flushable_packet_boundary_flag_supported(void){
802     // No. 54, byte 6, bit 6
803     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
804 }
805 
806 static int gap_ssp_supported(void){
807     // No. 51, byte 6, bit 3
808     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
809 }
810 
811 static int hci_classic_supported(void){
812     // No. 37, byte 4, bit 5, = No BR/EDR Support
813     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
814 }
815 
816 static int hci_le_supported(void){
817 #ifdef ENABLE_BLE
818     // No. 37, byte 4, bit 6 = LE Supported (Controller)
819     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
820 #else
821     return 0;
822 #endif
823 }
824 
825 // get addr type and address used in advertisement packets
826 void gap_advertisements_get_address(uint8_t * addr_type, bd_addr_t  addr){
827     *addr_type = hci_stack->adv_addr_type;
828     if (hci_stack->adv_addr_type){
829         memcpy(addr, hci_stack->adv_address, 6);
830     } else {
831         memcpy(addr, hci_stack->local_bd_addr, 6);
832     }
833 }
834 
835 #ifdef ENABLE_BLE
836 void le_handle_advertisement_report(uint8_t *packet, int size){
837     int offset = 3;
838     int num_reports = packet[offset];
839     offset += 1;
840 
841     int i;
842     // log_info("HCI: handle adv report with num reports: %d", num_reports);
843     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
844     for (i=0; i<num_reports;i++){
845         uint8_t data_length = packet[offset + 8];
846         uint8_t event_size = 10 + data_length;
847         int pos = 0;
848         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
849         event[pos++] = event_size;
850         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
851         offset += 8;
852         pos += 8;
853         event[pos++] = packet[offset + 1 + data_length]; // rssi
854         event[pos++] = packet[offset++]; //data_length;
855         memcpy(&event[pos], &packet[offset], data_length);
856         pos += data_length;
857         offset += data_length + 1; // rssi
858         hci_emit_event(event, pos, 1);
859     }
860 }
861 #endif
862 
863 static uint32_t hci_transport_uart_get_main_baud_rate(void){
864     if (!hci_stack->config) return 0;
865     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
866     // Limit baud rate for Broadcom chipsets to 3 mbps
867     if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
868         baud_rate = 3000000;
869     }
870     return baud_rate;
871 }
872 
873 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
874     switch (hci_stack->substate){
875         case HCI_INIT_W4_SEND_RESET:
876             log_info("Resend HCI Reset");
877             hci_stack->substate = HCI_INIT_SEND_RESET;
878             hci_stack->num_cmd_packets = 1;
879             hci_run();
880             break;
881         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
882             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
883             if (hci_stack->hci_transport->reset_link){
884                 hci_stack->hci_transport->reset_link();
885             }
886             // NOTE: explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
887         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
888             log_info("Resend HCI Reset - CSR Warm Boot");
889             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
890             hci_stack->num_cmd_packets = 1;
891             hci_run();
892             break;
893         case HCI_INIT_W4_SEND_BAUD_CHANGE:
894             if (hci_stack->hci_transport->set_baudrate){
895                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
896                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
897                 hci_stack->hci_transport->set_baudrate(baud_rate);
898             }
899             // For CSR, HCI Reset is sent on new baud rate
900             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
901                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
902                 hci_run();
903             }
904             break;
905         default:
906             break;
907     }
908 }
909 
910 static void hci_initializing_next_state(void){
911     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
912 }
913 
914 // assumption: hci_can_send_command_packet_now() == true
915 static void hci_initializing_run(void){
916     log_info("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
917     switch (hci_stack->substate){
918         case HCI_INIT_SEND_RESET:
919             hci_state_reset();
920 
921 #ifndef HAVE_PLATFORM_IPHONE_OS
922             // prepare reset if command complete not received in 100ms
923             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
924             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
925             btstack_run_loop_add_timer(&hci_stack->timeout);
926 #endif
927             // send command
928             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
929             hci_send_cmd(&hci_reset);
930             break;
931         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
932             hci_send_cmd(&hci_read_local_version_information);
933             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
934             break;
935         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
936             hci_state_reset();
937             // prepare reset if command complete not received in 100ms
938             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
939             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
940             btstack_run_loop_add_timer(&hci_stack->timeout);
941             // send command
942             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
943             hci_send_cmd(&hci_reset);
944             break;
945         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
946             hci_state_reset();
947             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
948             hci_send_cmd(&hci_reset);
949             break;
950         case HCI_INIT_SEND_BAUD_CHANGE: {
951             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
952             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
953             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
954             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
955             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
956             // STLC25000D: baudrate change happens within 0.5 s after command was send,
957             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
958             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
959                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
960                 btstack_run_loop_add_timer(&hci_stack->timeout);
961             }
962             break;
963         }
964         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
965             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
966             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
967             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
968             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
969             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
970             break;
971         }
972         case HCI_INIT_CUSTOM_INIT:
973             log_info("Custom init");
974             // Custom initialization
975             if (hci_stack->chipset && hci_stack->chipset->next_command){
976                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
977                 if (valid_cmd){
978                     int size = 3 + hci_stack->hci_packet_buffer[2];
979                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
980                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
981                     switch (valid_cmd) {
982                         case 1:
983                         default:
984                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
985                             break;
986                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
987                             log_info("CSR Warm Boot");
988                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
989                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
990                             btstack_run_loop_add_timer(&hci_stack->timeout);
991                             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO
992                                 && hci_stack->config
993                                 && hci_stack->chipset
994                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
995                                 && hci_stack->hci_transport->set_baudrate
996                                 && hci_transport_uart_get_main_baud_rate()){
997                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
998                             } else {
999                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1000                             }
1001                             break;
1002                     }
1003                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1004                     break;
1005                 }
1006                 log_info("hci_run: init script done");
1007 
1008                 // Init script download causes baud rate to reset on Broadcom chipsets, restore UART baud rate if needed
1009                 if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1010                     int need_baud_change = hci_stack->config
1011                         && hci_stack->chipset
1012                         && hci_stack->chipset->set_baudrate_command
1013                         && hci_stack->hci_transport->set_baudrate
1014                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1015                     if (need_baud_change) {
1016                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1017                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1018                         hci_stack->hci_transport->set_baudrate(baud_rate);
1019                     }
1020                 }
1021             }
1022             // otherwise continue
1023             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1024             hci_send_cmd(&hci_read_local_supported_commands);
1025             break;
1026         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1027             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1028             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1029             hci_send_cmd(&hci_read_local_supported_commands);
1030             break;
1031         case HCI_INIT_SET_BD_ADDR:
1032             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1033             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1034             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1035             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1036             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1037             break;
1038         case HCI_INIT_READ_BD_ADDR:
1039             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1040             hci_send_cmd(&hci_read_bd_addr);
1041             break;
1042         case HCI_INIT_READ_BUFFER_SIZE:
1043             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1044             hci_send_cmd(&hci_read_buffer_size);
1045             break;
1046         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1047             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1048             hci_send_cmd(&hci_read_local_supported_features);
1049             break;
1050         case HCI_INIT_SET_EVENT_MASK:
1051             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1052             if (hci_le_supported()){
1053                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1054             } else {
1055                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1056                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1057             }
1058             break;
1059         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1060             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1061             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1062             break;
1063         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1064             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1065             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1066             break;
1067         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1068             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1069             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1070             break;
1071         case HCI_INIT_WRITE_LOCAL_NAME:
1072             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1073             if (hci_stack->local_name){
1074                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1075             } else {
1076                 char local_name[8+17+1];
1077                 // BTstack 11:22:33:44:55:66
1078                 memcpy(local_name, "BTstack ", 8);
1079                 memcpy(&local_name[8], bd_addr_to_str(hci_stack->local_bd_addr), 17);   // strlen(bd_addr_to_str(...)) = 17
1080                 local_name[8+17] = '\0';
1081                 log_info("---> Name %s", local_name);
1082                 hci_send_cmd(&hci_write_local_name, local_name);
1083             }
1084             break;
1085         case HCI_INIT_WRITE_INQUIRY_MODE:
1086             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1087             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1088             break;
1089         case HCI_INIT_WRITE_SCAN_ENABLE:
1090             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1091             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1092             break;
1093         // only sent if ENABLE_SCO_OVER_HCI is defined
1094         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1095             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1096             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1097             break;
1098         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1099             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1100             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1101             break;
1102 #ifdef ENABLE_BLE
1103         // LE INIT
1104         case HCI_INIT_LE_READ_BUFFER_SIZE:
1105             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1106             hci_send_cmd(&hci_le_read_buffer_size);
1107             break;
1108         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1109             // LE Supported Host = 1, Simultaneous Host = 0
1110             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1111             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1112             break;
1113         case HCI_INIT_READ_WHITE_LIST_SIZE:
1114             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1115             hci_send_cmd(&hci_le_read_white_list_size);
1116             break;
1117         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1118             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, public address, accept all advs
1119             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1120             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, 0, 0);
1121             break;
1122 #endif
1123         default:
1124             return;
1125     }
1126 }
1127 
1128 static void hci_init_done(void){
1129     // done. tell the app
1130     log_info("hci_init_done -> HCI_STATE_WORKING");
1131     hci_stack->state = HCI_STATE_WORKING;
1132     hci_emit_state();
1133     hci_run();
1134 }
1135 
1136 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1137     uint8_t command_completed = 0;
1138 
1139     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1140         uint16_t opcode = little_endian_read_16(packet,3);
1141         if (opcode == hci_stack->last_cmd_opcode){
1142             command_completed = 1;
1143             log_info("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1144         } else {
1145             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1146         }
1147     }
1148 
1149     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1150         uint8_t  status = packet[2];
1151         uint16_t opcode = little_endian_read_16(packet,4);
1152         if (opcode == hci_stack->last_cmd_opcode){
1153             if (status){
1154                 command_completed = 1;
1155                 log_error("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1156             } else {
1157                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1158             }
1159         } else {
1160             log_info("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1161         }
1162     }
1163 
1164     // Vendor == CSR
1165     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1166         // TODO: track actual command
1167         command_completed = 1;
1168     }
1169 
1170     // Vendor == Toshiba
1171     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1172         // TODO: track actual command
1173         command_completed = 1;
1174     }
1175 
1176     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1177     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1178     //
1179     // HCI Reset
1180     // Timeout 100 ms
1181     // HCI Reset
1182     // Command Complete Reset
1183     // HCI Read Local Version Information
1184     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1185     // hang...
1186     //
1187     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1188     if (!command_completed
1189             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1190             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1191 
1192         uint16_t opcode = little_endian_read_16(packet,3);
1193         if (opcode == hci_reset.opcode){
1194             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1195             return;
1196         }
1197     }
1198 
1199     // CSR & H5
1200     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1201     if (!command_completed
1202             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1203             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1204 
1205         uint16_t opcode = little_endian_read_16(packet,3);
1206         if (opcode == hci_reset.opcode){
1207             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1208             return;
1209         }
1210     }
1211 
1212     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1213     // fix: Correct substate and behave as command below
1214     if (command_completed){
1215         switch (hci_stack->substate){
1216             case HCI_INIT_SEND_RESET:
1217                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1218                 break;
1219             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1220                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1221                 break;
1222             default:
1223                 break;
1224         }
1225     }
1226 
1227 
1228     if (!command_completed) return;
1229 
1230     int need_baud_change = hci_stack->config
1231                         && hci_stack->chipset
1232                         && hci_stack->chipset->set_baudrate_command
1233                         && hci_stack->hci_transport->set_baudrate
1234                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1235 
1236     int need_addr_change = hci_stack->custom_bd_addr_set
1237                         && hci_stack->chipset
1238                         && hci_stack->chipset->set_bd_addr_command;
1239 
1240     switch(hci_stack->substate){
1241         case HCI_INIT_SEND_RESET:
1242             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1243             // fix: just correct substate and behave as command below
1244             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1245             btstack_run_loop_remove_timer(&hci_stack->timeout);
1246             break;
1247         case HCI_INIT_W4_SEND_RESET:
1248             btstack_run_loop_remove_timer(&hci_stack->timeout);
1249             break;
1250         case HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION:
1251             log_info("Received local version info, need baud change %u", need_baud_change);
1252             if (need_baud_change){
1253                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1254                 return;
1255             }
1256             // skip baud change
1257             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1258             return;
1259         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1260             // for STLC2500D, baud rate change already happened.
1261             // for others, baud rate gets changed now
1262             if ((hci_stack->manufacturer != COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1263                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1264                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1265                 hci_stack->hci_transport->set_baudrate(baud_rate);
1266             }
1267             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1268             return;
1269         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1270             btstack_run_loop_remove_timer(&hci_stack->timeout);
1271             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1272             return;
1273         case HCI_INIT_W4_CUSTOM_INIT:
1274             // repeat custom init
1275             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1276             return;
1277         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1278             if (need_baud_change && hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1279                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1280                 return;
1281             }
1282             if (need_addr_change){
1283                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1284                 return;
1285             }
1286             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1287             return;
1288         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1289             if (need_baud_change){
1290                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1291                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1292                 hci_stack->hci_transport->set_baudrate(baud_rate);
1293             }
1294             if (need_addr_change){
1295                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1296                 return;
1297             }
1298             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1299             return;
1300         case HCI_INIT_W4_SET_BD_ADDR:
1301             // for STLC2500D, bd addr change only gets active after sending reset command
1302             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1303                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1304                 return;
1305             }
1306             // skipping st warm boot
1307             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1308             return;
1309         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1310             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1311             return;
1312         case HCI_INIT_W4_READ_BD_ADDR:
1313             // only read buffer size if supported
1314             if (hci_stack->local_supported_commands[0] & 0x01) {
1315                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1316                 return;
1317             }
1318             // skipping read buffer size
1319             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1320             return;
1321         case HCI_INIT_W4_SET_EVENT_MASK:
1322             // skip Classic init commands for LE only chipsets
1323             if (!hci_classic_supported()){
1324                 if (hci_le_supported()){
1325                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1326                     return;
1327                 } else {
1328                     log_error("Neither BR/EDR nor LE supported");
1329                     hci_init_done();
1330                     return;
1331                 }
1332             }
1333             if (!gap_ssp_supported()){
1334                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1335                 return;
1336             }
1337             break;
1338         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1339             break;
1340         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1341             // skip write le host if not supported (e.g. on LE only EM9301)
1342             if (hci_stack->local_supported_commands[0] & 0x02) break;
1343             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1344             return;
1345 
1346 #ifdef ENABLE_SCO_OVER_HCI
1347         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1348         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1349             break;
1350         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1351             if (!hci_le_supported()){
1352                 // SKIP LE init for Classic only configuration
1353                 hci_init_done();
1354                 return;
1355             }
1356             break;
1357 #else
1358         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1359             if (!hci_le_supported()){
1360                 // SKIP LE init for Classic only configuration
1361                 hci_init_done();
1362                 return;
1363             }
1364 #endif
1365             break;
1366         // Response to command before init done state -> init done
1367         case (HCI_INIT_DONE-1):
1368             hci_init_done();
1369             return;
1370 
1371         default:
1372             break;
1373     }
1374     hci_initializing_next_state();
1375 }
1376 
1377 static void event_handler(uint8_t *packet, int size){
1378 
1379     uint16_t event_length = packet[1];
1380 
1381     // assert packet is complete
1382     if (size != event_length + 2){
1383         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
1384         return;
1385     }
1386 
1387     bd_addr_t addr;
1388     bd_addr_type_t addr_type;
1389     uint8_t link_type;
1390     hci_con_handle_t handle;
1391     hci_connection_t * conn;
1392     int i;
1393 
1394     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1395 
1396     switch (hci_event_packet_get_type(packet)) {
1397 
1398         case HCI_EVENT_COMMAND_COMPLETE:
1399             // get num cmd packets
1400             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u", hci_stack->num_cmd_packets, packet[2]);
1401             hci_stack->num_cmd_packets = packet[2];
1402 
1403             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1404                 // from offset 5
1405                 // status
1406                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1407                 hci_stack->acl_data_packet_length = little_endian_read_16(packet, 6);
1408                 hci_stack->sco_data_packet_length = packet[8];
1409                 hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1410                 hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1411 
1412                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1413                     // determine usable ACL payload size
1414                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1415                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1416                     }
1417                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1418                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1419                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1420                 }
1421             }
1422 #ifdef ENABLE_BLE
1423             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1424                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1425                 hci_stack->le_acl_packets_total_num  = packet[8];
1426                     // determine usable ACL payload size
1427                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1428                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1429                     }
1430                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1431             }
1432             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1433                 hci_stack->le_whitelist_capacity = little_endian_read_16(packet, 6);
1434                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1435             }
1436 #endif
1437             // Dump local address
1438             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1439                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1440 				hci_stack->local_bd_addr);
1441                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1442                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1443                 if (hci_stack->link_key_db){
1444                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1445                 }
1446             }
1447             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1448                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1449             }
1450             // Note: HCI init checks
1451             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1452                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1453 
1454                 // determine usable ACL packet types based on host buffer size and supported features
1455                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1456                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1457 
1458                 // Classic/LE
1459                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1460             }
1461             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1462                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1463                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1464                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1465                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1466                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1467                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1468                 // notify app
1469                 if (hci_stack->local_version_information_callback){
1470                     hci_stack->local_version_information_callback(packet);
1471                 }
1472             }
1473             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1474                 hci_stack->local_supported_commands[0] =
1475                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0X80) >> 7 |  // Octet 14, bit 7
1476                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5;   // Octet 24, bit 6
1477             }
1478             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1479                 if (packet[5] == 0){
1480                     hci_stack->synchronous_flow_control_enabled = 1;
1481                 }
1482             }
1483             break;
1484 
1485         case HCI_EVENT_COMMAND_STATUS:
1486             // get num cmd packets
1487             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u", hci_stack->num_cmd_packets, packet[3]);
1488             hci_stack->num_cmd_packets = packet[3];
1489             break;
1490 
1491         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1492             int offset = 3;
1493             for (i=0; i<packet[2];i++){
1494                 handle = little_endian_read_16(packet, offset);
1495                 offset += 2;
1496                 uint16_t num_packets = little_endian_read_16(packet, offset);
1497                 offset += 2;
1498 
1499                 conn = hci_connection_for_handle(handle);
1500                 if (!conn){
1501                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1502                     continue;
1503                 }
1504 
1505                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1506                     if (conn->num_sco_packets_sent >= num_packets){
1507                         conn->num_sco_packets_sent -= num_packets;
1508                     } else {
1509                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1510                         conn->num_sco_packets_sent = 0;
1511                     }
1512                     hci_notify_if_sco_can_send_now();
1513                 } else {
1514                     if (conn->num_acl_packets_sent >= num_packets){
1515                         conn->num_acl_packets_sent -= num_packets;
1516                     } else {
1517                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1518                         conn->num_acl_packets_sent = 0;
1519                     }
1520                 }
1521                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1522             }
1523             break;
1524         }
1525         case HCI_EVENT_CONNECTION_REQUEST:
1526             reverse_bd_addr(&packet[2], addr);
1527             // TODO: eval COD 8-10
1528             link_type = packet[11];
1529             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1530             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1531             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1532             if (!conn) {
1533                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1534             }
1535             if (!conn) {
1536                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1537                 hci_stack->decline_reason = 0x0d;
1538                 bd_addr_copy(hci_stack->decline_addr, addr);
1539                 break;
1540             }
1541             conn->role  = HCI_ROLE_SLAVE;
1542             conn->state = RECEIVED_CONNECTION_REQUEST;
1543             // store info about eSCO
1544             if (link_type == 0x02){
1545                 conn->remote_supported_feature_eSCO = 1;
1546             }
1547             hci_run();
1548             break;
1549 
1550         case HCI_EVENT_CONNECTION_COMPLETE:
1551             // Connection management
1552             reverse_bd_addr(&packet[5], addr);
1553             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1554             addr_type = BD_ADDR_TYPE_CLASSIC;
1555             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1556             if (conn) {
1557                 if (!packet[2]){
1558                     conn->state = OPEN;
1559                     conn->con_handle = little_endian_read_16(packet, 3);
1560                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1561 
1562                     // restart timer
1563                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1564                     btstack_run_loop_add_timer(&conn->timeout);
1565 
1566                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1567 
1568                     hci_emit_nr_connections_changed();
1569                 } else {
1570                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1571                     uint8_t status = packet[2];
1572                     bd_addr_t bd_address;
1573                     memcpy(&bd_address, conn->address, 6);
1574 
1575                     // connection failed, remove entry
1576                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1577                     btstack_memory_hci_connection_free( conn );
1578 
1579                     // notify client if dedicated bonding
1580                     if (notify_dedicated_bonding_failed){
1581                         log_info("hci notify_dedicated_bonding_failed");
1582                         hci_emit_dedicated_bonding_result(bd_address, status);
1583                     }
1584 
1585                     // if authentication error, also delete link key
1586                     if (packet[2] == 0x05) {
1587                         gap_drop_link_key_for_bd_addr(addr);
1588                     }
1589                 }
1590             }
1591             break;
1592 
1593         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1594             reverse_bd_addr(&packet[5], addr);
1595             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1596             if (packet[2]){
1597                 // connection failed
1598                 break;
1599             }
1600             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1601             if (!conn) {
1602                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1603             }
1604             if (!conn) {
1605                 break;
1606             }
1607             conn->state = OPEN;
1608             conn->con_handle = little_endian_read_16(packet, 3);
1609             break;
1610 
1611         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1612             handle = little_endian_read_16(packet, 3);
1613             conn = hci_connection_for_handle(handle);
1614             if (!conn) break;
1615             if (!packet[2]){
1616                 uint8_t * features = &packet[5];
1617                 if (features[6] & (1 << 3)){
1618                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1619                 }
1620                 if (features[3] & (1<<7)){
1621                     conn->remote_supported_feature_eSCO = 1;
1622                 }
1623             }
1624             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1625             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1626             if (conn->bonding_flags & BONDING_DEDICATED){
1627                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1628             }
1629             break;
1630 
1631         case HCI_EVENT_LINK_KEY_REQUEST:
1632             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1633             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1634             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1635             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1636             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1637             hci_run();
1638             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1639             return;
1640 
1641         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1642             reverse_bd_addr(&packet[2], addr);
1643             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1644             if (!conn) break;
1645             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1646             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1647             // Change Connection Encryption keeps link key type
1648             if (link_key_type != CHANGED_COMBINATION_KEY){
1649                 conn->link_key_type = link_key_type;
1650             }
1651             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1652             // still forward event to allow dismiss of pairing dialog
1653             break;
1654         }
1655 
1656         case HCI_EVENT_PIN_CODE_REQUEST:
1657             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1658             // non-bondable mode: pin code negative reply will be sent
1659             if (!hci_stack->bondable){
1660                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1661                 hci_run();
1662                 return;
1663             }
1664             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1665             if (!hci_stack->link_key_db) break;
1666             hci_event_pin_code_request_get_bd_addr(packet, addr);
1667             hci_stack->link_key_db->delete_link_key(addr);
1668             break;
1669 
1670         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1671             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1672             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1673             break;
1674 
1675         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1676             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1677             if (!hci_stack->ssp_auto_accept) break;
1678             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1679             break;
1680 
1681         case HCI_EVENT_USER_PASSKEY_REQUEST:
1682             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1683             if (!hci_stack->ssp_auto_accept) break;
1684             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1685             break;
1686 
1687         case HCI_EVENT_ENCRYPTION_CHANGE:
1688             handle = little_endian_read_16(packet, 3);
1689             conn = hci_connection_for_handle(handle);
1690             if (!conn) break;
1691             if (packet[2] == 0) {
1692                 if (packet[5]){
1693                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1694                 } else {
1695                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1696                 }
1697             }
1698             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1699             break;
1700 
1701         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1702             handle = little_endian_read_16(packet, 3);
1703             conn = hci_connection_for_handle(handle);
1704             if (!conn) break;
1705 
1706             // dedicated bonding: send result and disconnect
1707             if (conn->bonding_flags & BONDING_DEDICATED){
1708                 conn->bonding_flags &= ~BONDING_DEDICATED;
1709                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1710                 conn->bonding_status = packet[2];
1711                 break;
1712             }
1713 
1714             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1715                 // link key sufficient for requested security
1716                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1717                 break;
1718             }
1719             // not enough
1720             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1721             break;
1722 
1723         // HCI_EVENT_DISCONNECTION_COMPLETE
1724         // has been split, to first notify stack before shutting connection down
1725         // see end of function, too.
1726         case HCI_EVENT_DISCONNECTION_COMPLETE:
1727             if (packet[2]) break;   // status != 0
1728             handle = little_endian_read_16(packet, 3);
1729             // drop outgoing ACL fragments if it is for closed connection
1730             if (hci_stack->acl_fragmentation_total_size > 0) {
1731                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
1732                     log_info("hci: drop fragmented ACL data for closed connection");
1733                      hci_stack->acl_fragmentation_total_size = 0;
1734                      hci_stack->acl_fragmentation_pos = 0;
1735                 }
1736             }
1737             // re-enable advertisements for le connections if active
1738             conn = hci_connection_for_handle(handle);
1739             if (!conn) break;
1740             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1741                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1742             }
1743             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1744             break;
1745 
1746         case HCI_EVENT_HARDWARE_ERROR:
1747             log_error("Hardware Error: 0x%02x", packet[2]);
1748             if (hci_stack->hardware_error_callback){
1749                 (*hci_stack->hardware_error_callback)(packet[2]);
1750             } else {
1751                 // if no special requests, just reboot stack
1752                 hci_power_control_off();
1753                 hci_power_control_on();
1754             }
1755             break;
1756 
1757         case HCI_EVENT_ROLE_CHANGE:
1758             if (packet[2]) break;   // status != 0
1759             handle = little_endian_read_16(packet, 3);
1760             conn = hci_connection_for_handle(handle);
1761             if (!conn) break;       // no conn
1762             conn->role = packet[9];
1763             break;
1764 
1765         case HCI_EVENT_TRANSPORT_PACKET_SENT:
1766             // release packet buffer only for asynchronous transport and if there are not further fragements
1767             if (hci_transport_synchronous()) {
1768                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
1769                 return; // instead of break: to avoid re-entering hci_run()
1770             }
1771             if (hci_stack->acl_fragmentation_total_size) break;
1772             hci_release_packet_buffer();
1773 
1774             // L2CAP receives this event via the hci_emit_event below
1775 
1776             // For SCO, we do the can_send_now_check here
1777             hci_notify_if_sco_can_send_now();
1778             break;
1779 
1780         case HCI_EVENT_SCO_CAN_SEND_NOW:
1781             // For SCO, we do the can_send_now_check here
1782             hci_notify_if_sco_can_send_now();
1783             return;
1784 
1785 #ifdef ENABLE_BLE
1786         case HCI_EVENT_LE_META:
1787             switch (packet[2]){
1788                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1789                     // log_info("advertising report received");
1790                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1791                     le_handle_advertisement_report(packet, size);
1792                     break;
1793                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1794                     // Connection management
1795                     reverse_bd_addr(&packet[8], addr);
1796                     addr_type = (bd_addr_type_t)packet[7];
1797                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1798                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1799                     // if auto-connect, remove from whitelist in both roles
1800                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1801                         hci_remove_from_whitelist(addr_type, addr);
1802                     }
1803                     // handle error: error is reported only to the initiator -> outgoing connection
1804                     if (packet[3]){
1805                         // outgoing connection establishment is done
1806                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1807                         // remove entry
1808                         if (conn){
1809                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1810                             btstack_memory_hci_connection_free( conn );
1811                         }
1812                         break;
1813                     }
1814                     // on success, both hosts receive connection complete event
1815                     if (packet[6] == HCI_ROLE_MASTER){
1816                         // if we're master, it was an outgoing connection and we're done with it
1817                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1818                     } else {
1819                         // if we're slave, it was an incoming connection, advertisements have stopped
1820                         hci_stack->le_advertisements_active = 0;
1821                     }
1822                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1823                     if (!conn){
1824                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1825                     }
1826                     // no memory, sorry.
1827                     if (!conn){
1828                         break;
1829                     }
1830 
1831                     conn->state = OPEN;
1832                     conn->role  = packet[6];
1833                     conn->con_handle = little_endian_read_16(packet, 4);
1834 
1835                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1836 
1837                     // restart timer
1838                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1839                     // btstack_run_loop_add_timer(&conn->timeout);
1840 
1841                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1842 
1843                     hci_emit_nr_connections_changed();
1844                     break;
1845 
1846             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
1847 
1848                 default:
1849                     break;
1850             }
1851             break;
1852 #endif
1853         default:
1854             break;
1855     }
1856 
1857     // handle BT initialization
1858     if (hci_stack->state == HCI_STATE_INITIALIZING){
1859         hci_initializing_event_handler(packet, size);
1860     }
1861 
1862     // help with BT sleep
1863     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
1864         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
1865         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1866         hci_initializing_next_state();
1867     }
1868 
1869     // notify upper stack
1870 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
1871 
1872     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
1873     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
1874         if (!packet[2]){
1875             handle = little_endian_read_16(packet, 3);
1876             hci_connection_t * aConn = hci_connection_for_handle(handle);
1877             if (aConn) {
1878                 uint8_t status = aConn->bonding_status;
1879                 uint16_t flags = aConn->bonding_flags;
1880                 bd_addr_t bd_address;
1881                 memcpy(&bd_address, aConn->address, 6);
1882                 hci_shutdown_connection(aConn);
1883                 // connection struct is gone, don't access anymore
1884                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
1885                     hci_emit_dedicated_bonding_result(bd_address, status);
1886                 }
1887             }
1888         }
1889     }
1890 
1891 	// execute main loop
1892 	hci_run();
1893 }
1894 
1895 static void sco_handler(uint8_t * packet, uint16_t size){
1896     if (!hci_stack->sco_packet_handler) return;
1897     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
1898 }
1899 
1900 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
1901     hci_dump_packet(packet_type, 1, packet, size);
1902     switch (packet_type) {
1903         case HCI_EVENT_PACKET:
1904             event_handler(packet, size);
1905             break;
1906         case HCI_ACL_DATA_PACKET:
1907             acl_handler(packet, size);
1908             break;
1909         case HCI_SCO_DATA_PACKET:
1910             sco_handler(packet, size);
1911         default:
1912             break;
1913     }
1914 }
1915 
1916 /**
1917  * @brief Add event packet handler.
1918  */
1919 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
1920     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
1921 }
1922 
1923 
1924 /** Register HCI packet handlers */
1925 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
1926     hci_stack->acl_packet_handler = handler;
1927 }
1928 
1929 /**
1930  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
1931  */
1932 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
1933     hci_stack->sco_packet_handler = handler;
1934 }
1935 
1936 static void hci_state_reset(void){
1937     // no connections yet
1938     hci_stack->connections = NULL;
1939 
1940     // keep discoverable/connectable as this has been requested by the client(s)
1941     // hci_stack->discoverable = 0;
1942     // hci_stack->connectable = 0;
1943     // hci_stack->bondable = 1;
1944 
1945     // buffer is free
1946     hci_stack->hci_packet_buffer_reserved = 0;
1947 
1948     // no pending cmds
1949     hci_stack->decline_reason = 0;
1950     hci_stack->new_scan_enable_value = 0xff;
1951 
1952     // LE
1953     hci_stack->adv_addr_type = 0;
1954     memset(hci_stack->adv_address, 0, 6);
1955     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1956     hci_stack->le_scan_type = 0xff;
1957     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1958     hci_stack->le_whitelist = 0;
1959     hci_stack->le_whitelist_capacity = 0;
1960     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
1961     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
1962     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
1963     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
1964     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
1965     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
1966 }
1967 
1968 /**
1969  * @brief Configure Bluetooth hardware control. Has to be called before power on.
1970  */
1971 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
1972     // store and open remote device db
1973     hci_stack->link_key_db = link_key_db;
1974     if (hci_stack->link_key_db) {
1975         hci_stack->link_key_db->open();
1976     }
1977 }
1978 
1979 void hci_init(const hci_transport_t *transport, const void *config){
1980 
1981 #ifdef HAVE_MALLOC
1982     if (!hci_stack) {
1983         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
1984     }
1985 #else
1986     hci_stack = &hci_stack_static;
1987 #endif
1988     memset(hci_stack, 0, sizeof(hci_stack_t));
1989 
1990     // reference to use transport layer implementation
1991     hci_stack->hci_transport = transport;
1992 
1993     // reference to used config
1994     hci_stack->config = config;
1995 
1996     // setup pointer for outgoing packet buffer
1997     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
1998 
1999     // max acl payload size defined in config.h
2000     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2001 
2002     // register packet handlers with transport
2003     transport->register_packet_handler(&packet_handler);
2004 
2005     hci_stack->state = HCI_STATE_OFF;
2006 
2007     // class of device
2008     hci_stack->class_of_device = 0x007a020c; // Smartphone
2009 
2010     // bondable by default
2011     hci_stack->bondable = 1;
2012 
2013     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2014     hci_stack->ssp_enable = 1;
2015     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2016     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2017     hci_stack->ssp_auto_accept = 1;
2018 
2019     // voice setting - signed 8 bit pcm data with CVSD over the air
2020     hci_stack->sco_voice_setting = 0x40;
2021 
2022     hci_state_reset();
2023 }
2024 
2025 /**
2026  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2027  */
2028 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2029     hci_stack->chipset = chipset_driver;
2030 
2031     // reset chipset driver - init is also called on power_up
2032     if (hci_stack->chipset && hci_stack->chipset->init){
2033         hci_stack->chipset->init(hci_stack->config);
2034     }
2035 }
2036 
2037 /**
2038  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2039  */
2040 void hci_set_control(const btstack_control_t *hardware_control){
2041     // references to used control implementation
2042     hci_stack->control = hardware_control;
2043     // init with transport config
2044     hardware_control->init(hci_stack->config);
2045 }
2046 
2047 void hci_close(void){
2048     // close remote device db
2049     if (hci_stack->link_key_db) {
2050         hci_stack->link_key_db->close();
2051     }
2052 
2053     btstack_linked_list_iterator_t lit;
2054     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2055     while (btstack_linked_list_iterator_has_next(&lit)){
2056         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2057         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2058         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2059         hci_shutdown_connection(connection);
2060     }
2061 
2062     hci_power_control(HCI_POWER_OFF);
2063 
2064 #ifdef HAVE_MALLOC
2065     free(hci_stack);
2066 #endif
2067     hci_stack = NULL;
2068 }
2069 
2070 void gap_set_class_of_device(uint32_t class_of_device){
2071     hci_stack->class_of_device = class_of_device;
2072 }
2073 
2074 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2075 void hci_set_bd_addr(bd_addr_t addr){
2076     memcpy(hci_stack->custom_bd_addr, addr, 6);
2077     hci_stack->custom_bd_addr_set = 1;
2078 }
2079 
2080 void hci_disable_l2cap_timeout_check(void){
2081     disable_l2cap_timeouts = 1;
2082 }
2083 // State-Module-Driver overview
2084 // state                    module  low-level
2085 // HCI_STATE_OFF             off      close
2086 // HCI_STATE_INITIALIZING,   on       open
2087 // HCI_STATE_WORKING,        on       open
2088 // HCI_STATE_HALTING,        on       open
2089 // HCI_STATE_SLEEPING,    off/sleep   close
2090 // HCI_STATE_FALLING_ASLEEP  on       open
2091 
2092 static int hci_power_control_on(void){
2093 
2094     // power on
2095     int err = 0;
2096     if (hci_stack->control && hci_stack->control->on){
2097         err = (*hci_stack->control->on)();
2098     }
2099     if (err){
2100         log_error( "POWER_ON failed");
2101         hci_emit_hci_open_failed();
2102         return err;
2103     }
2104 
2105     // int chipset driver
2106     if (hci_stack->chipset && hci_stack->chipset->init){
2107         hci_stack->chipset->init(hci_stack->config);
2108     }
2109 
2110     // init transport
2111     if (hci_stack->hci_transport->init){
2112         hci_stack->hci_transport->init(hci_stack->config);
2113     }
2114 
2115     // open transport
2116     err = hci_stack->hci_transport->open();
2117     if (err){
2118         log_error( "HCI_INIT failed, turning Bluetooth off again");
2119         if (hci_stack->control && hci_stack->control->off){
2120             (*hci_stack->control->off)();
2121         }
2122         hci_emit_hci_open_failed();
2123         return err;
2124     }
2125     return 0;
2126 }
2127 
2128 static void hci_power_control_off(void){
2129 
2130     log_info("hci_power_control_off");
2131 
2132     // close low-level device
2133     hci_stack->hci_transport->close();
2134 
2135     log_info("hci_power_control_off - hci_transport closed");
2136 
2137     // power off
2138     if (hci_stack->control && hci_stack->control->off){
2139         (*hci_stack->control->off)();
2140     }
2141 
2142     log_info("hci_power_control_off - control closed");
2143 
2144     hci_stack->state = HCI_STATE_OFF;
2145 }
2146 
2147 static void hci_power_control_sleep(void){
2148 
2149     log_info("hci_power_control_sleep");
2150 
2151 #if 0
2152     // don't close serial port during sleep
2153 
2154     // close low-level device
2155     hci_stack->hci_transport->close(hci_stack->config);
2156 #endif
2157 
2158     // sleep mode
2159     if (hci_stack->control && hci_stack->control->sleep){
2160         (*hci_stack->control->sleep)();
2161     }
2162 
2163     hci_stack->state = HCI_STATE_SLEEPING;
2164 }
2165 
2166 static int hci_power_control_wake(void){
2167 
2168     log_info("hci_power_control_wake");
2169 
2170     // wake on
2171     if (hci_stack->control && hci_stack->control->wake){
2172         (*hci_stack->control->wake)();
2173     }
2174 
2175 #if 0
2176     // open low-level device
2177     int err = hci_stack->hci_transport->open(hci_stack->config);
2178     if (err){
2179         log_error( "HCI_INIT failed, turning Bluetooth off again");
2180         if (hci_stack->control && hci_stack->control->off){
2181             (*hci_stack->control->off)();
2182         }
2183         hci_emit_hci_open_failed();
2184         return err;
2185     }
2186 #endif
2187 
2188     return 0;
2189 }
2190 
2191 static void hci_power_transition_to_initializing(void){
2192     // set up state machine
2193     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2194     hci_stack->hci_packet_buffer_reserved = 0;
2195     hci_stack->state = HCI_STATE_INITIALIZING;
2196     hci_stack->substate = HCI_INIT_SEND_RESET;
2197 }
2198 
2199 int hci_power_control(HCI_POWER_MODE power_mode){
2200 
2201     log_info("hci_power_control: %u, current mode %u", power_mode, hci_stack->state);
2202 
2203     int err = 0;
2204     switch (hci_stack->state){
2205 
2206         case HCI_STATE_OFF:
2207             switch (power_mode){
2208                 case HCI_POWER_ON:
2209                     err = hci_power_control_on();
2210                     if (err) {
2211                         log_error("hci_power_control_on() error %u", err);
2212                         return err;
2213                     }
2214                     hci_power_transition_to_initializing();
2215                     break;
2216                 case HCI_POWER_OFF:
2217                     // do nothing
2218                     break;
2219                 case HCI_POWER_SLEEP:
2220                     // do nothing (with SLEEP == OFF)
2221                     break;
2222             }
2223             break;
2224 
2225         case HCI_STATE_INITIALIZING:
2226             switch (power_mode){
2227                 case HCI_POWER_ON:
2228                     // do nothing
2229                     break;
2230                 case HCI_POWER_OFF:
2231                     // no connections yet, just turn it off
2232                     hci_power_control_off();
2233                     break;
2234                 case HCI_POWER_SLEEP:
2235                     // no connections yet, just turn it off
2236                     hci_power_control_sleep();
2237                     break;
2238             }
2239             break;
2240 
2241         case HCI_STATE_WORKING:
2242             switch (power_mode){
2243                 case HCI_POWER_ON:
2244                     // do nothing
2245                     break;
2246                 case HCI_POWER_OFF:
2247                     // see hci_run
2248                     hci_stack->state = HCI_STATE_HALTING;
2249                     break;
2250                 case HCI_POWER_SLEEP:
2251                     // see hci_run
2252                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2253                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2254                     break;
2255             }
2256             break;
2257 
2258         case HCI_STATE_HALTING:
2259             switch (power_mode){
2260                 case HCI_POWER_ON:
2261                     hci_power_transition_to_initializing();
2262                     break;
2263                 case HCI_POWER_OFF:
2264                     // do nothing
2265                     break;
2266                 case HCI_POWER_SLEEP:
2267                     // see hci_run
2268                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2269                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2270                     break;
2271             }
2272             break;
2273 
2274         case HCI_STATE_FALLING_ASLEEP:
2275             switch (power_mode){
2276                 case HCI_POWER_ON:
2277 
2278 #ifdef HAVE_PLATFORM_IPHONE_OS
2279                     // nothing to do, if H4 supports power management
2280                     if (btstack_control_iphone_power_management_enabled()){
2281                         hci_stack->state = HCI_STATE_INITIALIZING;
2282                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2283                         break;
2284                     }
2285 #endif
2286                     hci_power_transition_to_initializing();
2287                     break;
2288                 case HCI_POWER_OFF:
2289                     // see hci_run
2290                     hci_stack->state = HCI_STATE_HALTING;
2291                     break;
2292                 case HCI_POWER_SLEEP:
2293                     // do nothing
2294                     break;
2295             }
2296             break;
2297 
2298         case HCI_STATE_SLEEPING:
2299             switch (power_mode){
2300                 case HCI_POWER_ON:
2301 
2302 #ifdef HAVE_PLATFORM_IPHONE_OS
2303                     // nothing to do, if H4 supports power management
2304                     if (btstack_control_iphone_power_management_enabled()){
2305                         hci_stack->state = HCI_STATE_INITIALIZING;
2306                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2307                         hci_update_scan_enable();
2308                         break;
2309                     }
2310 #endif
2311                     err = hci_power_control_wake();
2312                     if (err) return err;
2313                     hci_power_transition_to_initializing();
2314                     break;
2315                 case HCI_POWER_OFF:
2316                     hci_stack->state = HCI_STATE_HALTING;
2317                     break;
2318                 case HCI_POWER_SLEEP:
2319                     // do nothing
2320                     break;
2321             }
2322             break;
2323     }
2324 
2325     // create internal event
2326 	hci_emit_state();
2327 
2328 	// trigger next/first action
2329 	hci_run();
2330 
2331     return 0;
2332 }
2333 
2334 static void hci_update_scan_enable(void){
2335     // 2 = page scan, 1 = inq scan
2336     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2337     hci_run();
2338 }
2339 
2340 void gap_discoverable_control(uint8_t enable){
2341     if (enable) enable = 1; // normalize argument
2342 
2343     if (hci_stack->discoverable == enable){
2344         hci_emit_discoverable_enabled(hci_stack->discoverable);
2345         return;
2346     }
2347 
2348     hci_stack->discoverable = enable;
2349     hci_update_scan_enable();
2350 }
2351 
2352 void gap_connectable_control(uint8_t enable){
2353     if (enable) enable = 1; // normalize argument
2354 
2355     // don't emit event
2356     if (hci_stack->connectable == enable) return;
2357 
2358     hci_stack->connectable = enable;
2359     hci_update_scan_enable();
2360 }
2361 
2362 void gap_local_bd_addr(bd_addr_t address_buffer){
2363     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2364 }
2365 
2366 static void hci_run(void){
2367 
2368     // log_info("hci_run: entered");
2369     btstack_linked_item_t * it;
2370 
2371     // send continuation fragments first, as they block the prepared packet buffer
2372     if (hci_stack->acl_fragmentation_total_size > 0) {
2373         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2374         hci_connection_t *connection = hci_connection_for_handle(con_handle);
2375         if (connection) {
2376             if (hci_can_send_prepared_acl_packet_now(con_handle)){
2377                 hci_send_acl_packet_fragments(connection);
2378                 return;
2379             }
2380         } else {
2381             // connection gone -> discard further fragments
2382             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
2383             hci_stack->acl_fragmentation_total_size = 0;
2384             hci_stack->acl_fragmentation_pos = 0;
2385         }
2386     }
2387 
2388     if (!hci_can_send_command_packet_now()) return;
2389 
2390     // global/non-connection oriented commands
2391 
2392     // decline incoming connections
2393     if (hci_stack->decline_reason){
2394         uint8_t reason = hci_stack->decline_reason;
2395         hci_stack->decline_reason = 0;
2396         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2397         return;
2398     }
2399 
2400     // send scan enable
2401     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2402         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2403         hci_stack->new_scan_enable_value = 0xff;
2404         return;
2405     }
2406 
2407 #ifdef ENABLE_BLE
2408     if (hci_stack->state == HCI_STATE_WORKING){
2409         // handle le scan
2410         switch(hci_stack->le_scanning_state){
2411             case LE_START_SCAN:
2412                 hci_stack->le_scanning_state = LE_SCANNING;
2413                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2414                 return;
2415 
2416             case LE_STOP_SCAN:
2417                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2418                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2419                 return;
2420             default:
2421                 break;
2422         }
2423         if (hci_stack->le_scan_type != 0xff){
2424             // defaults: active scanning, accept all advertisement packets
2425             int scan_type = hci_stack->le_scan_type;
2426             hci_stack->le_scan_type = 0xff;
2427             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);
2428             return;
2429         }
2430         // le advertisement control
2431         if (hci_stack->le_advertisements_todo){
2432             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2433         }
2434         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2435             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2436             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2437             return;
2438         }
2439         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2440             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2441             hci_send_cmd(&hci_le_set_advertising_parameters,
2442                  hci_stack->le_advertisements_interval_min,
2443                  hci_stack->le_advertisements_interval_max,
2444                  hci_stack->le_advertisements_type,
2445                  hci_stack->le_advertisements_own_address_type,
2446                  hci_stack->le_advertisements_direct_address_type,
2447                  hci_stack->le_advertisements_direct_address,
2448                  hci_stack->le_advertisements_channel_map,
2449                  hci_stack->le_advertisements_filter_policy);
2450             return;
2451         }
2452         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2453             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2454             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2455                 hci_stack->le_advertisements_data);
2456             return;
2457         }
2458         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2459             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2460             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2461                 hci_stack->le_scan_response_data);
2462             return;
2463         }
2464         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2465             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2466             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2467             return;
2468         }
2469 
2470         //
2471         // LE Whitelist Management
2472         //
2473 
2474         // check if whitelist needs modification
2475         btstack_linked_list_iterator_t lit;
2476         int modification_pending = 0;
2477         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2478         while (btstack_linked_list_iterator_has_next(&lit)){
2479             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2480             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2481                 modification_pending = 1;
2482                 break;
2483             }
2484         }
2485 
2486         if (modification_pending){
2487             // stop connnecting if modification pending
2488             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2489                 hci_send_cmd(&hci_le_create_connection_cancel);
2490                 return;
2491             }
2492 
2493             // add/remove entries
2494             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2495             while (btstack_linked_list_iterator_has_next(&lit)){
2496                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2497                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2498                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2499                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2500                     return;
2501 
2502                 }
2503                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2504                     bd_addr_t address;
2505                     bd_addr_type_t address_type = entry->address_type;
2506                     memcpy(address, entry->address, 6);
2507                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2508                     btstack_memory_whitelist_entry_free(entry);
2509                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2510                     return;
2511                 }
2512             }
2513         }
2514 
2515         // start connecting
2516         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2517             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2518             bd_addr_t null_addr;
2519             memset(null_addr, 0, 6);
2520             hci_send_cmd(&hci_le_create_connection,
2521                  0x0060,    // scan interval: 60 ms
2522                  0x0030,    // scan interval: 30 ms
2523                  1,         // use whitelist
2524                  0,         // peer address type
2525                  null_addr,      // peer bd addr
2526                  hci_stack->adv_addr_type, // our addr type:
2527                  0x0008,    // conn interval min
2528                  0x0018,    // conn interval max
2529                  0,         // conn latency
2530                  0x0048,    // supervision timeout
2531                  0x0001,    // min ce length
2532                  0x0001     // max ce length
2533                  );
2534             return;
2535         }
2536     }
2537 #endif
2538 
2539     // send pending HCI commands
2540     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2541         hci_connection_t * connection = (hci_connection_t *) it;
2542 
2543         switch(connection->state){
2544             case SEND_CREATE_CONNECTION:
2545                 switch(connection->address_type){
2546                     case BD_ADDR_TYPE_CLASSIC:
2547                         log_info("sending hci_create_connection");
2548                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2549                         break;
2550                     default:
2551 #ifdef ENABLE_BLE
2552                         log_info("sending hci_le_create_connection");
2553                         hci_send_cmd(&hci_le_create_connection,
2554                                      0x0060,    // scan interval: 60 ms
2555                                      0x0030,    // scan interval: 30 ms
2556                                      0,         // don't use whitelist
2557                                      connection->address_type, // peer address type
2558                                      connection->address,      // peer bd addr
2559                                      hci_stack->adv_addr_type, // our addr type:
2560                                      0x0008,    // conn interval min
2561                                      0x0018,    // conn interval max
2562                                      0,         // conn latency
2563                                      0x0048,    // supervision timeout
2564                                      0x0001,    // min ce length
2565                                      0x0001     // max ce length
2566                                      );
2567 
2568                         connection->state = SENT_CREATE_CONNECTION;
2569 #endif
2570                         break;
2571                 }
2572                 return;
2573 
2574             case RECEIVED_CONNECTION_REQUEST:
2575                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2576                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2577                 connection->role  = HCI_ROLE_SLAVE;
2578                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2579                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2580                 }
2581                 return;
2582 
2583 #ifdef ENABLE_BLE
2584             case SEND_CANCEL_CONNECTION:
2585                 connection->state = SENT_CANCEL_CONNECTION;
2586                 hci_send_cmd(&hci_le_create_connection_cancel);
2587                 return;
2588 #endif
2589             case SEND_DISCONNECT:
2590                 connection->state = SENT_DISCONNECT;
2591                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2592                 return;
2593 
2594             default:
2595                 break;
2596         }
2597 
2598         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2599             log_info("responding to link key request");
2600             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2601             link_key_t link_key;
2602             link_key_type_t link_key_type;
2603             if ( hci_stack->link_key_db
2604               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2605               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2606                connection->link_key_type = link_key_type;
2607                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2608             } else {
2609                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2610             }
2611             return;
2612         }
2613 
2614         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2615             log_info("denying to pin request");
2616             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2617             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2618             return;
2619         }
2620 
2621         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2622             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2623             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2624             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2625                 // tweak authentication requirements
2626                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2627                 if (connection->bonding_flags & BONDING_DEDICATED){
2628                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2629                 }
2630                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2631                     authreq |= 1;
2632                 }
2633                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2634             } else {
2635                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2636             }
2637             return;
2638         }
2639 
2640         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2641             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2642             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2643             return;
2644         }
2645 
2646         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2647             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2648             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2649             return;
2650         }
2651 
2652         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2653             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2654             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2655             return;
2656         }
2657 
2658         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2659             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2660             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2661             return;
2662         }
2663         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2664             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2665             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2666             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2667             return;
2668         }
2669         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2670             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2671             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2672             return;
2673         }
2674         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2675             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2676             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2677             return;
2678         }
2679 
2680 #ifdef ENABLE_BLE
2681         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2682             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2683 
2684             uint16_t connection_interval_min = connection->le_conn_interval_min;
2685             connection->le_conn_interval_min = 0;
2686             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2687                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2688                 0x0000, 0xffff);
2689         }
2690 #endif
2691     }
2692 
2693     hci_connection_t * connection;
2694     switch (hci_stack->state){
2695         case HCI_STATE_INITIALIZING:
2696             hci_initializing_run();
2697             break;
2698 
2699         case HCI_STATE_HALTING:
2700 
2701             log_info("HCI_STATE_HALTING");
2702 
2703             // free whitelist entries
2704 #ifdef ENABLE_BLE
2705             {
2706                 btstack_linked_list_iterator_t lit;
2707                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2708                 while (btstack_linked_list_iterator_has_next(&lit)){
2709                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2710                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2711                     btstack_memory_whitelist_entry_free(entry);
2712                 }
2713             }
2714 #endif
2715             // close all open connections
2716             connection =  (hci_connection_t *) hci_stack->connections;
2717             if (connection){
2718                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2719                 if (!hci_can_send_command_packet_now()) return;
2720 
2721                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2722 
2723                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2724                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2725 
2726                 // ... which would be ignored anyway as we shutdown (free) the connection now
2727                 hci_shutdown_connection(connection);
2728 
2729                 // finally, send the disconnect command
2730                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2731                 return;
2732             }
2733             log_info("HCI_STATE_HALTING, calling off");
2734 
2735             // switch mode
2736             hci_power_control_off();
2737 
2738             log_info("HCI_STATE_HALTING, emitting state");
2739             hci_emit_state();
2740             log_info("HCI_STATE_HALTING, done");
2741             break;
2742 
2743         case HCI_STATE_FALLING_ASLEEP:
2744             switch(hci_stack->substate) {
2745                 case HCI_FALLING_ASLEEP_DISCONNECT:
2746                     log_info("HCI_STATE_FALLING_ASLEEP");
2747                     // close all open connections
2748                     connection =  (hci_connection_t *) hci_stack->connections;
2749 
2750 #ifdef HAVE_PLATFORM_IPHONE_OS
2751                     // don't close connections, if H4 supports power management
2752                     if (btstack_control_iphone_power_management_enabled()){
2753                         connection = NULL;
2754                     }
2755 #endif
2756                     if (connection){
2757 
2758                         // send disconnect
2759                         if (!hci_can_send_command_packet_now()) return;
2760 
2761                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2762                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2763 
2764                         // send disconnected event right away - causes higher layer connections to get closed, too.
2765                         hci_shutdown_connection(connection);
2766                         return;
2767                     }
2768 
2769                     if (hci_classic_supported()){
2770                         // disable page and inquiry scan
2771                         if (!hci_can_send_command_packet_now()) return;
2772 
2773                         log_info("HCI_STATE_HALTING, disabling inq scans");
2774                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2775 
2776                         // continue in next sub state
2777                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2778                         break;
2779                     }
2780                     // fall through for ble-only chips
2781 
2782                 case HCI_FALLING_ASLEEP_COMPLETE:
2783                     log_info("HCI_STATE_HALTING, calling sleep");
2784 #ifdef HAVE_PLATFORM_IPHONE_OS
2785                     // don't actually go to sleep, if H4 supports power management
2786                     if (btstack_control_iphone_power_management_enabled()){
2787                         // SLEEP MODE reached
2788                         hci_stack->state = HCI_STATE_SLEEPING;
2789                         hci_emit_state();
2790                         break;
2791                     }
2792 #endif
2793                     // switch mode
2794                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2795                     hci_emit_state();
2796                     break;
2797 
2798                 default:
2799                     break;
2800             }
2801             break;
2802 
2803         default:
2804             break;
2805     }
2806 }
2807 
2808 int hci_send_cmd_packet(uint8_t *packet, int size){
2809     bd_addr_t addr;
2810     hci_connection_t * conn;
2811     // house-keeping
2812 
2813     // create_connection?
2814     if (IS_COMMAND(packet, hci_create_connection)){
2815         reverse_bd_addr(&packet[3], addr);
2816         log_info("Create_connection to %s", bd_addr_to_str(addr));
2817 
2818         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2819         if (!conn){
2820             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2821             if (!conn){
2822                 // notify client that alloc failed
2823                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
2824                 return 0; // don't sent packet to controller
2825             }
2826             conn->state = SEND_CREATE_CONNECTION;
2827         }
2828         log_info("conn state %u", conn->state);
2829         switch (conn->state){
2830             // if connection active exists
2831             case OPEN:
2832                 // and OPEN, emit connection complete command, don't send to controller
2833                 hci_emit_connection_complete(addr, conn->con_handle, 0);
2834                 return 0;
2835             case SEND_CREATE_CONNECTION:
2836                 // connection created by hci, e.g. dedicated bonding
2837                 break;
2838             default:
2839                 // otherwise, just ignore as it is already in the open process
2840                 return 0;
2841         }
2842         conn->state = SENT_CREATE_CONNECTION;
2843     }
2844     if (IS_COMMAND(packet, hci_link_key_request_reply)){
2845         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
2846     }
2847     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
2848         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
2849     }
2850 
2851     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
2852         if (hci_stack->link_key_db){
2853             reverse_bd_addr(&packet[3], addr);
2854             hci_stack->link_key_db->delete_link_key(addr);
2855         }
2856     }
2857 
2858     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
2859     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
2860         reverse_bd_addr(&packet[3], addr);
2861         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2862         if (conn){
2863             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
2864         }
2865     }
2866 
2867     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
2868     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
2869     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
2870     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
2871         reverse_bd_addr(&packet[3], addr);
2872         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2873         if (conn){
2874             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
2875         }
2876     }
2877 
2878     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2879         hci_stack->loopback_mode = packet[3];
2880     }
2881 
2882 #ifdef ENABLE_BLE
2883     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
2884         hci_stack->adv_addr_type = packet[8];
2885     }
2886     if (IS_COMMAND(packet, hci_le_set_random_address)){
2887         reverse_bd_addr(&packet[3], hci_stack->adv_address);
2888     }
2889     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
2890         hci_stack->le_advertisements_active = packet[3];
2891     }
2892     if (IS_COMMAND(packet, hci_le_create_connection)){
2893         // white list used?
2894         uint8_t initiator_filter_policy = packet[7];
2895         switch (initiator_filter_policy){
2896             case 0:
2897                 // whitelist not used
2898                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
2899                 break;
2900             case 1:
2901                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
2902                 break;
2903             default:
2904                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
2905                 break;
2906         }
2907     }
2908     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
2909         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2910     }
2911 #endif
2912 
2913     hci_stack->num_cmd_packets--;
2914 
2915     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2916     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2917 
2918     // release packet buffer for synchronous transport implementations
2919     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
2920         hci_stack->hci_packet_buffer_reserved = 0;
2921     }
2922 
2923     return err;
2924 }
2925 
2926 // disconnect because of security block
2927 void hci_disconnect_security_block(hci_con_handle_t con_handle){
2928     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2929     if (!connection) return;
2930     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2931 }
2932 
2933 
2934 // Configure Secure Simple Pairing
2935 
2936 // enable will enable SSP during init
2937 void gap_ssp_set_enable(int enable){
2938     hci_stack->ssp_enable = enable;
2939 }
2940 
2941 static int hci_local_ssp_activated(void){
2942     return gap_ssp_supported() && hci_stack->ssp_enable;
2943 }
2944 
2945 // if set, BTstack will respond to io capability request using authentication requirement
2946 void gap_ssp_set_io_capability(int io_capability){
2947     hci_stack->ssp_io_capability = io_capability;
2948 }
2949 void gap_ssp_set_authentication_requirement(int authentication_requirement){
2950     hci_stack->ssp_authentication_requirement = authentication_requirement;
2951 }
2952 
2953 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
2954 void gap_ssp_set_auto_accept(int auto_accept){
2955     hci_stack->ssp_auto_accept = auto_accept;
2956 }
2957 
2958 /**
2959  * pre: numcmds >= 0 - it's allowed to send a command to the controller
2960  */
2961 int hci_send_cmd(const hci_cmd_t *cmd, ...){
2962 
2963     if (!hci_can_send_command_packet_now()){
2964         log_error("hci_send_cmd called but cannot send packet now");
2965         return 0;
2966     }
2967 
2968     // for HCI INITIALIZATION
2969     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
2970     hci_stack->last_cmd_opcode = cmd->opcode;
2971 
2972     hci_reserve_packet_buffer();
2973     uint8_t * packet = hci_stack->hci_packet_buffer;
2974 
2975     va_list argptr;
2976     va_start(argptr, cmd);
2977     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
2978     va_end(argptr);
2979 
2980     return hci_send_cmd_packet(packet, size);
2981 }
2982 
2983 // Create various non-HCI events.
2984 // TODO: generalize, use table similar to hci_create_command
2985 
2986 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
2987     // dump packet
2988     if (dump) {
2989         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
2990     }
2991 
2992     // dispatch to all event handlers
2993     btstack_linked_list_iterator_t it;
2994     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
2995     while (btstack_linked_list_iterator_has_next(&it)){
2996         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
2997         entry->callback(HCI_EVENT_PACKET, 0, event, size);
2998     }
2999 }
3000 
3001 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
3002     if (!hci_stack->acl_packet_handler) return;
3003     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3004 }
3005 
3006 static void hci_notify_if_sco_can_send_now(void){
3007     // notify SCO sender if waiting
3008     if (!hci_stack->sco_waiting_for_can_send_now) return;
3009     if (hci_can_send_sco_packet_now()){
3010         hci_stack->sco_waiting_for_can_send_now = 0;
3011         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3012         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3013         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3014     }
3015 }
3016 
3017 void hci_emit_state(void){
3018     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3019     uint8_t event[3];
3020     event[0] = BTSTACK_EVENT_STATE;
3021     event[1] = sizeof(event) - 2;
3022     event[2] = hci_stack->state;
3023     hci_emit_event(event, sizeof(event), 1);
3024 }
3025 
3026 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3027     uint8_t event[13];
3028     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3029     event[1] = sizeof(event) - 2;
3030     event[2] = status;
3031     little_endian_store_16(event, 3, con_handle);
3032     reverse_bd_addr(address, &event[5]);
3033     event[11] = 1; // ACL connection
3034     event[12] = 0; // encryption disabled
3035     hci_emit_event(event, sizeof(event), 1);
3036 }
3037 
3038 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3039     uint8_t event[21];
3040     event[0] = HCI_EVENT_LE_META;
3041     event[1] = sizeof(event) - 2;
3042     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3043     event[3] = status;
3044     little_endian_store_16(event, 4, con_handle);
3045     event[6] = 0; // TODO: role
3046     event[7] = address_type;
3047     reverse_bd_addr(address, &event[8]);
3048     little_endian_store_16(event, 14, 0); // interval
3049     little_endian_store_16(event, 16, 0); // latency
3050     little_endian_store_16(event, 18, 0); // supervision timeout
3051     event[20] = 0; // master clock accuracy
3052     hci_emit_event(event, sizeof(event), 1);
3053 }
3054 
3055 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3056     uint8_t event[6];
3057     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3058     event[1] = sizeof(event) - 2;
3059     event[2] = 0; // status = OK
3060     little_endian_store_16(event, 3, con_handle);
3061     event[5] = reason;
3062     hci_emit_event(event, sizeof(event), 1);
3063 }
3064 
3065 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3066     if (disable_l2cap_timeouts) return;
3067     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3068     uint8_t event[4];
3069     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3070     event[1] = sizeof(event) - 2;
3071     little_endian_store_16(event, 2, conn->con_handle);
3072     hci_emit_event(event, sizeof(event), 1);
3073 }
3074 
3075 static void hci_emit_nr_connections_changed(void){
3076     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3077     uint8_t event[3];
3078     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3079     event[1] = sizeof(event) - 2;
3080     event[2] = nr_hci_connections();
3081     hci_emit_event(event, sizeof(event), 1);
3082 }
3083 
3084 static void hci_emit_hci_open_failed(void){
3085     log_info("BTSTACK_EVENT_POWERON_FAILED");
3086     uint8_t event[2];
3087     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3088     event[1] = sizeof(event) - 2;
3089     hci_emit_event(event, sizeof(event), 1);
3090 }
3091 
3092 static void hci_emit_discoverable_enabled(uint8_t enabled){
3093     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3094     uint8_t event[3];
3095     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3096     event[1] = sizeof(event) - 2;
3097     event[2] = enabled;
3098     hci_emit_event(event, sizeof(event), 1);
3099 }
3100 
3101 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3102     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3103     uint8_t event[5];
3104     int pos = 0;
3105     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3106     event[pos++] = sizeof(event) - 2;
3107     little_endian_store_16(event, 2, con_handle);
3108     pos += 2;
3109     event[pos++] = level;
3110     hci_emit_event(event, sizeof(event), 1);
3111 }
3112 
3113 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3114     log_info("hci_emit_dedicated_bonding_result %u ", status);
3115     uint8_t event[9];
3116     int pos = 0;
3117     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3118     event[pos++] = sizeof(event) - 2;
3119     event[pos++] = status;
3120     reverse_bd_addr(address, &event[pos]);
3121     hci_emit_event(event, sizeof(event), 1);
3122 }
3123 
3124 // query if remote side supports eSCO
3125 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3126     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3127     if (!connection) return 0;
3128     return connection->remote_supported_feature_eSCO;
3129 }
3130 
3131 // query if remote side supports SSP
3132 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3133     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3134     if (!connection) return 0;
3135     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3136 }
3137 
3138 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3139     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3140 }
3141 
3142 // GAP API
3143 /**
3144  * @bbrief enable/disable bonding. default is enabled
3145  * @praram enabled
3146  */
3147 void gap_set_bondable_mode(int enable){
3148     hci_stack->bondable = enable ? 1 : 0;
3149 }
3150 /**
3151  * @brief Get bondable mode.
3152  * @return 1 if bondable
3153  */
3154 int gap_get_bondable_mode(void){
3155     return hci_stack->bondable;
3156 }
3157 
3158 /**
3159  * @brief map link keys to security levels
3160  */
3161 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3162     switch (link_key_type){
3163         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3164             return LEVEL_4;
3165         case COMBINATION_KEY:
3166         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3167             return LEVEL_3;
3168         default:
3169             return LEVEL_2;
3170     }
3171 }
3172 
3173 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3174     if (!connection) return LEVEL_0;
3175     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3176     return gap_security_level_for_link_key_type(connection->link_key_type);
3177 }
3178 
3179 
3180 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3181     log_info("gap_mitm_protection_required_for_security_level %u", level);
3182     return level > LEVEL_2;
3183 }
3184 
3185 /**
3186  * @brief get current security level
3187  */
3188 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3189     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3190     if (!connection) return LEVEL_0;
3191     return gap_security_level_for_connection(connection);
3192 }
3193 
3194 /**
3195  * @brief request connection to device to
3196  * @result GAP_AUTHENTICATION_RESULT
3197  */
3198 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3199     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3200     if (!connection){
3201         hci_emit_security_level(con_handle, LEVEL_0);
3202         return;
3203     }
3204     gap_security_level_t current_level = gap_security_level(con_handle);
3205     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3206     if (current_level >= requested_level){
3207         hci_emit_security_level(con_handle, current_level);
3208         return;
3209     }
3210 
3211     connection->requested_security_level = requested_level;
3212 
3213 #if 0
3214     // sending encryption request without a link key results in an error.
3215     // TODO: figure out how to use it properly
3216 
3217     // would enabling ecnryption suffice (>= LEVEL_2)?
3218     if (hci_stack->link_key_db){
3219         link_key_type_t link_key_type;
3220         link_key_t      link_key;
3221         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3222             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3223                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3224                 return;
3225             }
3226         }
3227     }
3228 #endif
3229 
3230     // try to authenticate connection
3231     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3232     hci_run();
3233 }
3234 
3235 /**
3236  * @brief start dedicated bonding with device. disconnect after bonding
3237  * @param device
3238  * @param request MITM protection
3239  * @result GAP_DEDICATED_BONDING_COMPLETE
3240  */
3241 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3242 
3243     // create connection state machine
3244     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3245 
3246     if (!connection){
3247         return BTSTACK_MEMORY_ALLOC_FAILED;
3248     }
3249 
3250     // delete linkn key
3251     gap_drop_link_key_for_bd_addr(device);
3252 
3253     // configure LEVEL_2/3, dedicated bonding
3254     connection->state = SEND_CREATE_CONNECTION;
3255     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3256     log_info("gap_dedicated_bonding, mitm %u -> level %u", mitm_protection_required, connection->requested_security_level);
3257     connection->bonding_flags = BONDING_DEDICATED;
3258 
3259     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3260 
3261     // handle: connnection failure (connection complete != ok)
3262     // handle: authentication failure
3263     // handle: disconnect on done
3264 
3265     hci_run();
3266 
3267     return 0;
3268 }
3269 
3270 void gap_set_local_name(const char * local_name){
3271     hci_stack->local_name = local_name;
3272 }
3273 
3274 void gap_start_scan(void){
3275     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3276     hci_stack->le_scanning_state = LE_START_SCAN;
3277     hci_run();
3278 }
3279 
3280 void gap_stop_scan(void){
3281     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3282     hci_stack->le_scanning_state = LE_STOP_SCAN;
3283     hci_run();
3284 }
3285 
3286 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3287     hci_stack->le_scan_type     = scan_type;
3288     hci_stack->le_scan_interval = scan_interval;
3289     hci_stack->le_scan_window   = scan_window;
3290     hci_run();
3291 }
3292 
3293 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3294     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3295     if (!conn){
3296         log_info("gap_connect: no connection exists yet, creating context");
3297         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3298         if (!conn){
3299             // notify client that alloc failed
3300             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3301             log_info("gap_connect: failed to alloc hci_connection_t");
3302             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3303         }
3304         conn->state = SEND_CREATE_CONNECTION;
3305         log_info("gap_connect: send create connection next");
3306         hci_run();
3307         return 0;
3308     }
3309 
3310     if (!hci_is_le_connection(conn) ||
3311         conn->state == SEND_CREATE_CONNECTION ||
3312         conn->state == SENT_CREATE_CONNECTION) {
3313         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3314         log_error("gap_connect: classic connection or connect is already being created");
3315         return GATT_CLIENT_IN_WRONG_STATE;
3316     }
3317 
3318     log_info("gap_connect: context exists with state %u", conn->state);
3319     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3320     hci_run();
3321     return 0;
3322 }
3323 
3324 // @assumption: only a single outgoing LE Connection exists
3325 static hci_connection_t * gap_get_outgoing_connection(void){
3326     btstack_linked_item_t *it;
3327     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3328         hci_connection_t * conn = (hci_connection_t *) it;
3329         if (!hci_is_le_connection(conn)) continue;
3330         switch (conn->state){
3331             case SEND_CREATE_CONNECTION:
3332             case SENT_CREATE_CONNECTION:
3333                 return conn;
3334             default:
3335                 break;
3336         };
3337     }
3338     return NULL;
3339 }
3340 
3341 uint8_t gap_connect_cancel(void){
3342     hci_connection_t * conn = gap_get_outgoing_connection();
3343     if (!conn) return 0;
3344     switch (conn->state){
3345         case SEND_CREATE_CONNECTION:
3346             // skip sending create connection and emit event instead
3347             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3348             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3349             btstack_memory_hci_connection_free( conn );
3350             break;
3351         case SENT_CREATE_CONNECTION:
3352             // request to send cancel connection
3353             conn->state = SEND_CANCEL_CONNECTION;
3354             hci_run();
3355             break;
3356         default:
3357             break;
3358     }
3359     return 0;
3360 }
3361 
3362 /**
3363  * @brief Updates the connection parameters for a given LE connection
3364  * @param handle
3365  * @param conn_interval_min (unit: 1.25ms)
3366  * @param conn_interval_max (unit: 1.25ms)
3367  * @param conn_latency
3368  * @param supervision_timeout (unit: 10ms)
3369  * @returns 0 if ok
3370  */
3371 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3372     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3373     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3374     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3375     connection->le_conn_interval_min = conn_interval_min;
3376     connection->le_conn_interval_max = conn_interval_max;
3377     connection->le_conn_latency = conn_latency;
3378     connection->le_supervision_timeout = supervision_timeout;
3379     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3380     hci_run();
3381     return 0;
3382 }
3383 
3384 /**
3385  * @brief Request an update of the connection parameter for a given LE connection
3386  * @param handle
3387  * @param conn_interval_min (unit: 1.25ms)
3388  * @param conn_interval_max (unit: 1.25ms)
3389  * @param conn_latency
3390  * @param supervision_timeout (unit: 10ms)
3391  * @returns 0 if ok
3392  */
3393 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3394     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3395     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3396     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3397     connection->le_conn_interval_min = conn_interval_min;
3398     connection->le_conn_interval_max = conn_interval_max;
3399     connection->le_conn_latency = conn_latency;
3400     connection->le_supervision_timeout = supervision_timeout;
3401     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3402     hci_run();
3403     return 0;
3404 }
3405 
3406 static void gap_advertisments_changed(void){
3407     // disable advertisements before updating adv, scan data, or adv params
3408     if (hci_stack->le_advertisements_active){
3409         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3410     }
3411     hci_run();
3412 }
3413 
3414 /**
3415  * @brief Set Advertisement Data
3416  * @param advertising_data_length
3417  * @param advertising_data (max 31 octets)
3418  * @note data is not copied, pointer has to stay valid
3419  */
3420 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3421     hci_stack->le_advertisements_data_len = advertising_data_length;
3422     hci_stack->le_advertisements_data = advertising_data;
3423     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3424     gap_advertisments_changed();
3425 }
3426 
3427 /**
3428  * @brief Set Scan Response Data
3429  * @param advertising_data_length
3430  * @param advertising_data (max 31 octets)
3431  * @note data is not copied, pointer has to stay valid
3432  */
3433 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3434     hci_stack->le_scan_response_data_len = scan_response_data_length;
3435     hci_stack->le_scan_response_data = scan_response_data;
3436     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3437     gap_advertisments_changed();
3438 }
3439 
3440 /**
3441  * @brief Set Advertisement Parameters
3442  * @param adv_int_min
3443  * @param adv_int_max
3444  * @param adv_type
3445  * @param own_address_type
3446  * @param direct_address_type
3447  * @param direct_address
3448  * @param channel_map
3449  * @param filter_policy
3450  *
3451  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3452  */
3453  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3454     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3455     uint8_t channel_map, uint8_t filter_policy) {
3456 
3457     hci_stack->le_advertisements_interval_min = adv_int_min;
3458     hci_stack->le_advertisements_interval_max = adv_int_max;
3459     hci_stack->le_advertisements_type = adv_type;
3460     hci_stack->le_advertisements_own_address_type = own_address_type;
3461     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3462     hci_stack->le_advertisements_channel_map = channel_map;
3463     hci_stack->le_advertisements_filter_policy = filter_policy;
3464     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3465 
3466     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3467     gap_advertisments_changed();
3468  }
3469 
3470 /**
3471  * @brief Enable/Disable Advertisements
3472  * @param enabled
3473  */
3474 void gap_advertisements_enable(int enabled){
3475     hci_stack->le_advertisements_enabled = enabled;
3476     if (enabled && !hci_stack->le_advertisements_active){
3477         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3478     }
3479     if (!enabled && hci_stack->le_advertisements_active){
3480         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3481     }
3482     hci_run();
3483 }
3484 
3485 
3486 uint8_t gap_disconnect(hci_con_handle_t handle){
3487     hci_connection_t * conn = hci_connection_for_handle(handle);
3488     if (!conn){
3489         hci_emit_disconnection_complete(handle, 0);
3490         return 0;
3491     }
3492     conn->state = SEND_DISCONNECT;
3493     hci_run();
3494     return 0;
3495 }
3496 
3497 /**
3498  * @brief Get connection type
3499  * @param con_handle
3500  * @result connection_type
3501  */
3502 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3503     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3504     if (!conn) return GAP_CONNECTION_INVALID;
3505     switch (conn->address_type){
3506         case BD_ADDR_TYPE_LE_PUBLIC:
3507         case BD_ADDR_TYPE_LE_RANDOM:
3508             return GAP_CONNECTION_LE;
3509         case BD_ADDR_TYPE_SCO:
3510             return GAP_CONNECTION_SCO;
3511         case BD_ADDR_TYPE_CLASSIC:
3512             return GAP_CONNECTION_ACL;
3513         default:
3514             return GAP_CONNECTION_INVALID;
3515     }
3516 }
3517 
3518 #ifdef ENABLE_BLE
3519 
3520 /**
3521  * @brief Auto Connection Establishment - Start Connecting to device
3522  * @param address_typ
3523  * @param address
3524  * @returns 0 if ok
3525  */
3526 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3527     // check capacity
3528     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3529     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3530     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3531     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3532     entry->address_type = address_type;
3533     memcpy(entry->address, address, 6);
3534     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3535     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3536     hci_run();
3537     return 0;
3538 }
3539 
3540 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3541     btstack_linked_list_iterator_t it;
3542     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3543     while (btstack_linked_list_iterator_has_next(&it)){
3544         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3545         if (entry->address_type != address_type) continue;
3546         if (memcmp(entry->address, address, 6) != 0) continue;
3547         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3548             // remove from controller if already present
3549             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3550             continue;
3551         }
3552         // direclty remove entry from whitelist
3553         btstack_linked_list_iterator_remove(&it);
3554         btstack_memory_whitelist_entry_free(entry);
3555     }
3556 }
3557 
3558 /**
3559  * @brief Auto Connection Establishment - Stop Connecting to device
3560  * @param address_typ
3561  * @param address
3562  * @returns 0 if ok
3563  */
3564 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3565     hci_remove_from_whitelist(address_type, address);
3566     hci_run();
3567     return 0;
3568 }
3569 
3570 /**
3571  * @brief Auto Connection Establishment - Stop everything
3572  * @note  Convenience function to stop all active auto connection attempts
3573  */
3574 void gap_auto_connection_stop_all(void){
3575     btstack_linked_list_iterator_t it;
3576     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3577     while (btstack_linked_list_iterator_has_next(&it)){
3578         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3579         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3580             // remove from controller if already present
3581             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3582             continue;
3583         }
3584         // directly remove entry from whitelist
3585         btstack_linked_list_iterator_remove(&it);
3586         btstack_memory_whitelist_entry_free(entry);
3587     }
3588     hci_run();
3589 }
3590 
3591 #endif
3592 
3593 /**
3594  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
3595  * @param inquriy_mode see bluetooth_defines.h
3596  */
3597 void hci_set_inquiry_mode(inquiry_mode_t mode){
3598     hci_stack->inquiry_mode = mode;
3599 }
3600 
3601 /**
3602  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3603  */
3604 void hci_set_sco_voice_setting(uint16_t voice_setting){
3605     hci_stack->sco_voice_setting = voice_setting;
3606 }
3607 
3608 /**
3609  * @brief Get SCO Voice Setting
3610  * @return current voice setting
3611  */
3612 uint16_t hci_get_sco_voice_setting(void){
3613     return hci_stack->sco_voice_setting;
3614 }
3615 
3616 /** @brief Get SCO packet length for current SCO Voice setting
3617  *  @note  Using SCO packets of the exact length is required for USB transfer
3618  *  @return Length of SCO packets in bytes (not audio frames)
3619  */
3620 int hci_get_sco_packet_length(void){
3621     // see Core Spec for H2 USB Transfer.
3622     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3623     return 27;
3624 }
3625 
3626 /**
3627  * @brief Set callback for Bluetooth Hardware Error
3628  */
3629 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
3630     hci_stack->hardware_error_callback = fn;
3631 }
3632 
3633 /**
3634  * @brief Set callback for local information from Bluetooth controller right after HCI Reset
3635  * @note Can be used to select chipset driver dynamically during startup
3636  */
3637 void hci_set_local_version_information_callback(void (*fn)(uint8_t * local_version_information)){
3638     hci_stack->local_version_information_callback = fn;
3639 }
3640 
3641 void hci_disconnect_all(void){
3642     btstack_linked_list_iterator_t it;
3643     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3644     while (btstack_linked_list_iterator_has_next(&it)){
3645         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3646         if (con->state == SENT_DISCONNECT) continue;
3647         con->state = SEND_DISCONNECT;
3648     }
3649     hci_run();
3650 }
3651