xref: /btstack/src/hci.c (revision 6704d3d7a94df59e3b07f591430d5749b9c69be1)
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_SCAN_ENABLE:
1086             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1087             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1088             break;
1089         // only sent if ENABLE_SCO_OVER_HCI is defined
1090         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1091             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1092             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1093             break;
1094         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1095             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1096             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1097             break;
1098 #ifdef ENABLE_BLE
1099         // LE INIT
1100         case HCI_INIT_LE_READ_BUFFER_SIZE:
1101             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1102             hci_send_cmd(&hci_le_read_buffer_size);
1103             break;
1104         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1105             // LE Supported Host = 1, Simultaneous Host = 0
1106             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1107             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1108             break;
1109         case HCI_INIT_READ_WHITE_LIST_SIZE:
1110             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1111             hci_send_cmd(&hci_le_read_white_list_size);
1112             break;
1113         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1114             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, public address, accept all advs
1115             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1116             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, 0, 0);
1117             break;
1118 #endif
1119         default:
1120             return;
1121     }
1122 }
1123 
1124 static void hci_init_done(void){
1125     // done. tell the app
1126     log_info("hci_init_done -> HCI_STATE_WORKING");
1127     hci_stack->state = HCI_STATE_WORKING;
1128     hci_emit_state();
1129     hci_run();
1130 }
1131 
1132 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1133     uint8_t command_completed = 0;
1134 
1135     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1136         uint16_t opcode = little_endian_read_16(packet,3);
1137         if (opcode == hci_stack->last_cmd_opcode){
1138             command_completed = 1;
1139             log_info("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1140         } else {
1141             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1142         }
1143     }
1144 
1145     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1146         uint8_t  status = packet[2];
1147         uint16_t opcode = little_endian_read_16(packet,4);
1148         if (opcode == hci_stack->last_cmd_opcode){
1149             if (status){
1150                 command_completed = 1;
1151                 log_error("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1152             } else {
1153                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1154             }
1155         } else {
1156             log_info("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1157         }
1158     }
1159 
1160     // Vendor == CSR
1161     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1162         // TODO: track actual command
1163         command_completed = 1;
1164     }
1165 
1166     // Vendor == Toshiba
1167     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1168         // TODO: track actual command
1169         command_completed = 1;
1170     }
1171 
1172     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1173     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1174     //
1175     // HCI Reset
1176     // Timeout 100 ms
1177     // HCI Reset
1178     // Command Complete Reset
1179     // HCI Read Local Version Information
1180     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1181     // hang...
1182     //
1183     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1184     if (!command_completed
1185             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1186             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1187 
1188         uint16_t opcode = little_endian_read_16(packet,3);
1189         if (opcode == hci_reset.opcode){
1190             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1191             return;
1192         }
1193     }
1194 
1195     // CSR & H5
1196     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1197     if (!command_completed
1198             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1199             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1200 
1201         uint16_t opcode = little_endian_read_16(packet,3);
1202         if (opcode == hci_reset.opcode){
1203             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1204             return;
1205         }
1206     }
1207 
1208     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1209     // fix: Correct substate and behave as command below
1210     if (command_completed){
1211         switch (hci_stack->substate){
1212             case HCI_INIT_SEND_RESET:
1213                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1214                 break;
1215             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1216                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1217                 break;
1218             default:
1219                 break;
1220         }
1221     }
1222 
1223 
1224     if (!command_completed) return;
1225 
1226     int need_baud_change = hci_stack->config
1227                         && hci_stack->chipset
1228                         && hci_stack->chipset->set_baudrate_command
1229                         && hci_stack->hci_transport->set_baudrate
1230                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1231 
1232     int need_addr_change = hci_stack->custom_bd_addr_set
1233                         && hci_stack->chipset
1234                         && hci_stack->chipset->set_bd_addr_command;
1235 
1236     switch(hci_stack->substate){
1237         case HCI_INIT_SEND_RESET:
1238             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1239             // fix: just correct substate and behave as command below
1240             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1241             btstack_run_loop_remove_timer(&hci_stack->timeout);
1242             break;
1243         case HCI_INIT_W4_SEND_RESET:
1244             btstack_run_loop_remove_timer(&hci_stack->timeout);
1245             break;
1246         case HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION:
1247             log_info("Received local version info, need baud change %u", need_baud_change);
1248             if (need_baud_change){
1249                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1250                 return;
1251             }
1252             // skip baud change
1253             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1254             return;
1255         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1256             // for STLC2500D, baud rate change already happened.
1257             // for others, baud rate gets changed now
1258             if ((hci_stack->manufacturer != COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1259                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1260                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1261                 hci_stack->hci_transport->set_baudrate(baud_rate);
1262             }
1263             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1264             return;
1265         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1266             btstack_run_loop_remove_timer(&hci_stack->timeout);
1267             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1268             return;
1269         case HCI_INIT_W4_CUSTOM_INIT:
1270             // repeat custom init
1271             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1272             return;
1273         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1274             if (need_baud_change && hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1275                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1276                 return;
1277             }
1278             if (need_addr_change){
1279                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1280                 return;
1281             }
1282             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1283             return;
1284         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1285             if (need_baud_change){
1286                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1287                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1288                 hci_stack->hci_transport->set_baudrate(baud_rate);
1289             }
1290             if (need_addr_change){
1291                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1292                 return;
1293             }
1294             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1295             return;
1296         case HCI_INIT_W4_SET_BD_ADDR:
1297             // for STLC2500D, bd addr change only gets active after sending reset command
1298             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1299                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1300                 return;
1301             }
1302             // skipping st warm boot
1303             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1304             return;
1305         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1306             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1307             return;
1308         case HCI_INIT_W4_READ_BD_ADDR:
1309             // only read buffer size if supported
1310             if (hci_stack->local_supported_commands[0] & 0x01) {
1311                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1312                 return;
1313             }
1314             // skipping read buffer size
1315             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1316             return;
1317         case HCI_INIT_W4_SET_EVENT_MASK:
1318             // skip Classic init commands for LE only chipsets
1319             if (!hci_classic_supported()){
1320                 if (hci_le_supported()){
1321                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1322                     return;
1323                 } else {
1324                     log_error("Neither BR/EDR nor LE supported");
1325                     hci_init_done();
1326                     return;
1327                 }
1328             }
1329             if (!gap_ssp_supported()){
1330                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1331                 return;
1332             }
1333             break;
1334         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1335             break;
1336         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1337             // skip write le host if not supported (e.g. on LE only EM9301)
1338             if (hci_stack->local_supported_commands[0] & 0x02) break;
1339             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1340             return;
1341 
1342 #ifdef ENABLE_SCO_OVER_HCI
1343         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1344         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1345             break;
1346         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1347             if (!hci_le_supported()){
1348                 // SKIP LE init for Classic only configuration
1349                 hci_init_done();
1350                 return;
1351             }
1352             break;
1353 #else
1354         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1355             if (!hci_le_supported()){
1356                 // SKIP LE init for Classic only configuration
1357                 hci_init_done();
1358                 return;
1359             }
1360 #endif
1361             break;
1362         // Response to command before init done state -> init done
1363         case (HCI_INIT_DONE-1):
1364             hci_init_done();
1365             return;
1366 
1367         default:
1368             break;
1369     }
1370     hci_initializing_next_state();
1371 }
1372 
1373 static void event_handler(uint8_t *packet, int size){
1374 
1375     uint16_t event_length = packet[1];
1376 
1377     // assert packet is complete
1378     if (size != event_length + 2){
1379         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
1380         return;
1381     }
1382 
1383     bd_addr_t addr;
1384     bd_addr_type_t addr_type;
1385     uint8_t link_type;
1386     hci_con_handle_t handle;
1387     hci_connection_t * conn;
1388     int i;
1389 
1390     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1391 
1392     switch (hci_event_packet_get_type(packet)) {
1393 
1394         case HCI_EVENT_COMMAND_COMPLETE:
1395             // get num cmd packets
1396             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u", hci_stack->num_cmd_packets, packet[2]);
1397             hci_stack->num_cmd_packets = packet[2];
1398 
1399             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1400                 // from offset 5
1401                 // status
1402                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1403                 hci_stack->acl_data_packet_length = little_endian_read_16(packet, 6);
1404                 hci_stack->sco_data_packet_length = packet[8];
1405                 hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1406                 hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1407 
1408                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1409                     // determine usable ACL payload size
1410                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1411                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1412                     }
1413                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1414                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1415                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1416                 }
1417             }
1418 #ifdef ENABLE_BLE
1419             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1420                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1421                 hci_stack->le_acl_packets_total_num  = packet[8];
1422                     // determine usable ACL payload size
1423                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1424                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1425                     }
1426                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1427             }
1428             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1429                 hci_stack->le_whitelist_capacity = little_endian_read_16(packet, 6);
1430                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1431             }
1432 #endif
1433             // Dump local address
1434             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1435                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1436 				hci_stack->local_bd_addr);
1437                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1438                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1439                 if (hci_stack->link_key_db){
1440                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1441                 }
1442             }
1443             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1444                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1445             }
1446             // Note: HCI init checks
1447             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1448                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1449 
1450                 // determine usable ACL packet types based on host buffer size and supported features
1451                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1452                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
1453 
1454                 // Classic/LE
1455                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1456             }
1457             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1458                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1459                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1460                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1461                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1462                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1463                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1464                 // notify app
1465                 if (hci_stack->local_version_information_callback){
1466                     hci_stack->local_version_information_callback(packet);
1467                 }
1468             }
1469             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1470                 hci_stack->local_supported_commands[0] =
1471                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0X80) >> 7 |  // Octet 14, bit 7
1472                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5;   // Octet 24, bit 6
1473             }
1474             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1475                 if (packet[5] == 0){
1476                     hci_stack->synchronous_flow_control_enabled = 1;
1477                 }
1478             }
1479             break;
1480 
1481         case HCI_EVENT_COMMAND_STATUS:
1482             // get num cmd packets
1483             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u", hci_stack->num_cmd_packets, packet[3]);
1484             hci_stack->num_cmd_packets = packet[3];
1485             break;
1486 
1487         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1488             int offset = 3;
1489             for (i=0; i<packet[2];i++){
1490                 handle = little_endian_read_16(packet, offset);
1491                 offset += 2;
1492                 uint16_t num_packets = little_endian_read_16(packet, offset);
1493                 offset += 2;
1494 
1495                 conn = hci_connection_for_handle(handle);
1496                 if (!conn){
1497                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1498                     continue;
1499                 }
1500 
1501                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1502                     if (conn->num_sco_packets_sent >= num_packets){
1503                         conn->num_sco_packets_sent -= num_packets;
1504                     } else {
1505                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1506                         conn->num_sco_packets_sent = 0;
1507                     }
1508                     hci_notify_if_sco_can_send_now();
1509                 } else {
1510                     if (conn->num_acl_packets_sent >= num_packets){
1511                         conn->num_acl_packets_sent -= num_packets;
1512                     } else {
1513                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1514                         conn->num_acl_packets_sent = 0;
1515                     }
1516                 }
1517                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1518             }
1519             break;
1520         }
1521         case HCI_EVENT_CONNECTION_REQUEST:
1522             reverse_bd_addr(&packet[2], addr);
1523             // TODO: eval COD 8-10
1524             link_type = packet[11];
1525             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1526             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1527             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1528             if (!conn) {
1529                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1530             }
1531             if (!conn) {
1532                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1533                 hci_stack->decline_reason = 0x0d;
1534                 bd_addr_copy(hci_stack->decline_addr, addr);
1535                 break;
1536             }
1537             conn->role  = HCI_ROLE_SLAVE;
1538             conn->state = RECEIVED_CONNECTION_REQUEST;
1539             // store info about eSCO
1540             if (link_type == 0x02){
1541                 conn->remote_supported_feature_eSCO = 1;
1542             }
1543             hci_run();
1544             break;
1545 
1546         case HCI_EVENT_CONNECTION_COMPLETE:
1547             // Connection management
1548             reverse_bd_addr(&packet[5], addr);
1549             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1550             addr_type = BD_ADDR_TYPE_CLASSIC;
1551             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1552             if (conn) {
1553                 if (!packet[2]){
1554                     conn->state = OPEN;
1555                     conn->con_handle = little_endian_read_16(packet, 3);
1556                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1557 
1558                     // restart timer
1559                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1560                     btstack_run_loop_add_timer(&conn->timeout);
1561 
1562                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1563 
1564                     hci_emit_nr_connections_changed();
1565                 } else {
1566                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1567                     uint8_t status = packet[2];
1568                     bd_addr_t bd_address;
1569                     memcpy(&bd_address, conn->address, 6);
1570 
1571                     // connection failed, remove entry
1572                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1573                     btstack_memory_hci_connection_free( conn );
1574 
1575                     // notify client if dedicated bonding
1576                     if (notify_dedicated_bonding_failed){
1577                         log_info("hci notify_dedicated_bonding_failed");
1578                         hci_emit_dedicated_bonding_result(bd_address, status);
1579                     }
1580 
1581                     // if authentication error, also delete link key
1582                     if (packet[2] == 0x05) {
1583                         gap_drop_link_key_for_bd_addr(addr);
1584                     }
1585                 }
1586             }
1587             break;
1588 
1589         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1590             reverse_bd_addr(&packet[5], addr);
1591             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1592             if (packet[2]){
1593                 // connection failed
1594                 break;
1595             }
1596             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1597             if (!conn) {
1598                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1599             }
1600             if (!conn) {
1601                 break;
1602             }
1603             conn->state = OPEN;
1604             conn->con_handle = little_endian_read_16(packet, 3);
1605             break;
1606 
1607         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1608             handle = little_endian_read_16(packet, 3);
1609             conn = hci_connection_for_handle(handle);
1610             if (!conn) break;
1611             if (!packet[2]){
1612                 uint8_t * features = &packet[5];
1613                 if (features[6] & (1 << 3)){
1614                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1615                 }
1616                 if (features[3] & (1<<7)){
1617                     conn->remote_supported_feature_eSCO = 1;
1618                 }
1619             }
1620             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1621             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1622             if (conn->bonding_flags & BONDING_DEDICATED){
1623                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1624             }
1625             break;
1626 
1627         case HCI_EVENT_LINK_KEY_REQUEST:
1628             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1629             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1630             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1631             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1632             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1633             hci_run();
1634             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1635             return;
1636 
1637         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1638             reverse_bd_addr(&packet[2], addr);
1639             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1640             if (!conn) break;
1641             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1642             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1643             // Change Connection Encryption keeps link key type
1644             if (link_key_type != CHANGED_COMBINATION_KEY){
1645                 conn->link_key_type = link_key_type;
1646             }
1647             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1648             // still forward event to allow dismiss of pairing dialog
1649             break;
1650         }
1651 
1652         case HCI_EVENT_PIN_CODE_REQUEST:
1653             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1654             // non-bondable mode: pin code negative reply will be sent
1655             if (!hci_stack->bondable){
1656                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1657                 hci_run();
1658                 return;
1659             }
1660             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1661             if (!hci_stack->link_key_db) break;
1662             hci_event_pin_code_request_get_bd_addr(packet, addr);
1663             hci_stack->link_key_db->delete_link_key(addr);
1664             break;
1665 
1666         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1667             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1668             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1669             break;
1670 
1671         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1672             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1673             if (!hci_stack->ssp_auto_accept) break;
1674             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1675             break;
1676 
1677         case HCI_EVENT_USER_PASSKEY_REQUEST:
1678             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1679             if (!hci_stack->ssp_auto_accept) break;
1680             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1681             break;
1682 
1683         case HCI_EVENT_ENCRYPTION_CHANGE:
1684             handle = little_endian_read_16(packet, 3);
1685             conn = hci_connection_for_handle(handle);
1686             if (!conn) break;
1687             if (packet[2] == 0) {
1688                 if (packet[5]){
1689                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1690                 } else {
1691                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1692                 }
1693             }
1694             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1695             break;
1696 
1697         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1698             handle = little_endian_read_16(packet, 3);
1699             conn = hci_connection_for_handle(handle);
1700             if (!conn) break;
1701 
1702             // dedicated bonding: send result and disconnect
1703             if (conn->bonding_flags & BONDING_DEDICATED){
1704                 conn->bonding_flags &= ~BONDING_DEDICATED;
1705                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1706                 conn->bonding_status = packet[2];
1707                 break;
1708             }
1709 
1710             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1711                 // link key sufficient for requested security
1712                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1713                 break;
1714             }
1715             // not enough
1716             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1717             break;
1718 
1719         // HCI_EVENT_DISCONNECTION_COMPLETE
1720         // has been split, to first notify stack before shutting connection down
1721         // see end of function, too.
1722         case HCI_EVENT_DISCONNECTION_COMPLETE:
1723             if (packet[2]) break;   // status != 0
1724             handle = little_endian_read_16(packet, 3);
1725             // drop outgoing ACL fragments if it is for closed connection
1726             if (hci_stack->acl_fragmentation_total_size > 0) {
1727                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
1728                     log_info("hci: drop fragmented ACL data for closed connection");
1729                      hci_stack->acl_fragmentation_total_size = 0;
1730                      hci_stack->acl_fragmentation_pos = 0;
1731                 }
1732             }
1733             // re-enable advertisements for le connections if active
1734             conn = hci_connection_for_handle(handle);
1735             if (!conn) break;
1736             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1737                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1738             }
1739             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1740             break;
1741 
1742         case HCI_EVENT_HARDWARE_ERROR:
1743             log_error("Hardware Error: 0x%02x", packet[2]);
1744             if (hci_stack->hardware_error_callback){
1745                 (*hci_stack->hardware_error_callback)(packet[2]);
1746             } else {
1747                 // if no special requests, just reboot stack
1748                 hci_power_control_off();
1749                 hci_power_control_on();
1750             }
1751             break;
1752 
1753         case HCI_EVENT_ROLE_CHANGE:
1754             if (packet[2]) break;   // status != 0
1755             handle = little_endian_read_16(packet, 3);
1756             conn = hci_connection_for_handle(handle);
1757             if (!conn) break;       // no conn
1758             conn->role = packet[9];
1759             break;
1760 
1761         case HCI_EVENT_TRANSPORT_PACKET_SENT:
1762             // release packet buffer only for asynchronous transport and if there are not further fragements
1763             if (hci_transport_synchronous()) {
1764                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
1765                 return; // instead of break: to avoid re-entering hci_run()
1766             }
1767             if (hci_stack->acl_fragmentation_total_size) break;
1768             hci_release_packet_buffer();
1769 
1770             // L2CAP receives this event via the hci_emit_event below
1771 
1772             // For SCO, we do the can_send_now_check here
1773             hci_notify_if_sco_can_send_now();
1774             break;
1775 
1776         case HCI_EVENT_SCO_CAN_SEND_NOW:
1777             // For SCO, we do the can_send_now_check here
1778             hci_notify_if_sco_can_send_now();
1779             return;
1780 
1781 #ifdef ENABLE_BLE
1782         case HCI_EVENT_LE_META:
1783             switch (packet[2]){
1784                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1785                     // log_info("advertising report received");
1786                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1787                     le_handle_advertisement_report(packet, size);
1788                     break;
1789                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1790                     // Connection management
1791                     reverse_bd_addr(&packet[8], addr);
1792                     addr_type = (bd_addr_type_t)packet[7];
1793                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1794                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1795                     // if auto-connect, remove from whitelist in both roles
1796                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1797                         hci_remove_from_whitelist(addr_type, addr);
1798                     }
1799                     // handle error: error is reported only to the initiator -> outgoing connection
1800                     if (packet[3]){
1801                         // outgoing connection establishment is done
1802                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1803                         // remove entry
1804                         if (conn){
1805                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1806                             btstack_memory_hci_connection_free( conn );
1807                         }
1808                         break;
1809                     }
1810                     // on success, both hosts receive connection complete event
1811                     if (packet[6] == HCI_ROLE_MASTER){
1812                         // if we're master, it was an outgoing connection and we're done with it
1813                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1814                     } else {
1815                         // if we're slave, it was an incoming connection, advertisements have stopped
1816                         hci_stack->le_advertisements_active = 0;
1817                     }
1818                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1819                     if (!conn){
1820                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1821                     }
1822                     // no memory, sorry.
1823                     if (!conn){
1824                         break;
1825                     }
1826 
1827                     conn->state = OPEN;
1828                     conn->role  = packet[6];
1829                     conn->con_handle = little_endian_read_16(packet, 4);
1830 
1831                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1832 
1833                     // restart timer
1834                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1835                     // btstack_run_loop_add_timer(&conn->timeout);
1836 
1837                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1838 
1839                     hci_emit_nr_connections_changed();
1840                     break;
1841 
1842             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
1843 
1844                 default:
1845                     break;
1846             }
1847             break;
1848 #endif
1849         default:
1850             break;
1851     }
1852 
1853     // handle BT initialization
1854     if (hci_stack->state == HCI_STATE_INITIALIZING){
1855         hci_initializing_event_handler(packet, size);
1856     }
1857 
1858     // help with BT sleep
1859     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
1860         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
1861         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1862         hci_initializing_next_state();
1863     }
1864 
1865     // notify upper stack
1866 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
1867 
1868     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
1869     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
1870         if (!packet[2]){
1871             handle = little_endian_read_16(packet, 3);
1872             hci_connection_t * aConn = hci_connection_for_handle(handle);
1873             if (aConn) {
1874                 uint8_t status = aConn->bonding_status;
1875                 uint16_t flags = aConn->bonding_flags;
1876                 bd_addr_t bd_address;
1877                 memcpy(&bd_address, aConn->address, 6);
1878                 hci_shutdown_connection(aConn);
1879                 // connection struct is gone, don't access anymore
1880                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
1881                     hci_emit_dedicated_bonding_result(bd_address, status);
1882                 }
1883             }
1884         }
1885     }
1886 
1887 	// execute main loop
1888 	hci_run();
1889 }
1890 
1891 static void sco_handler(uint8_t * packet, uint16_t size){
1892     if (!hci_stack->sco_packet_handler) return;
1893     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
1894 }
1895 
1896 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
1897     hci_dump_packet(packet_type, 1, packet, size);
1898     switch (packet_type) {
1899         case HCI_EVENT_PACKET:
1900             event_handler(packet, size);
1901             break;
1902         case HCI_ACL_DATA_PACKET:
1903             acl_handler(packet, size);
1904             break;
1905         case HCI_SCO_DATA_PACKET:
1906             sco_handler(packet, size);
1907         default:
1908             break;
1909     }
1910 }
1911 
1912 /**
1913  * @brief Add event packet handler.
1914  */
1915 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
1916     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
1917 }
1918 
1919 
1920 /** Register HCI packet handlers */
1921 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
1922     hci_stack->acl_packet_handler = handler;
1923 }
1924 
1925 /**
1926  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
1927  */
1928 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
1929     hci_stack->sco_packet_handler = handler;
1930 }
1931 
1932 static void hci_state_reset(void){
1933     // no connections yet
1934     hci_stack->connections = NULL;
1935 
1936     // keep discoverable/connectable as this has been requested by the client(s)
1937     // hci_stack->discoverable = 0;
1938     // hci_stack->connectable = 0;
1939     // hci_stack->bondable = 1;
1940 
1941     // buffer is free
1942     hci_stack->hci_packet_buffer_reserved = 0;
1943 
1944     // no pending cmds
1945     hci_stack->decline_reason = 0;
1946     hci_stack->new_scan_enable_value = 0xff;
1947 
1948     // LE
1949     hci_stack->adv_addr_type = 0;
1950     memset(hci_stack->adv_address, 0, 6);
1951     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1952     hci_stack->le_scan_type = 0xff;
1953     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1954     hci_stack->le_whitelist = 0;
1955     hci_stack->le_whitelist_capacity = 0;
1956     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
1957     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
1958     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
1959     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
1960     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
1961     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
1962 }
1963 
1964 /**
1965  * @brief Configure Bluetooth hardware control. Has to be called before power on.
1966  */
1967 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
1968     // store and open remote device db
1969     hci_stack->link_key_db = link_key_db;
1970     if (hci_stack->link_key_db) {
1971         hci_stack->link_key_db->open();
1972     }
1973 }
1974 
1975 void hci_init(const hci_transport_t *transport, const void *config){
1976 
1977 #ifdef HAVE_MALLOC
1978     if (!hci_stack) {
1979         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
1980     }
1981 #else
1982     hci_stack = &hci_stack_static;
1983 #endif
1984     memset(hci_stack, 0, sizeof(hci_stack_t));
1985 
1986     // reference to use transport layer implementation
1987     hci_stack->hci_transport = transport;
1988 
1989     // reference to used config
1990     hci_stack->config = config;
1991 
1992     // setup pointer for outgoing packet buffer
1993     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
1994 
1995     // max acl payload size defined in config.h
1996     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1997 
1998     // register packet handlers with transport
1999     transport->register_packet_handler(&packet_handler);
2000 
2001     hci_stack->state = HCI_STATE_OFF;
2002 
2003     // class of device
2004     hci_stack->class_of_device = 0x007a020c; // Smartphone
2005 
2006     // bondable by default
2007     hci_stack->bondable = 1;
2008 
2009     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2010     hci_stack->ssp_enable = 1;
2011     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2012     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2013     hci_stack->ssp_auto_accept = 1;
2014 
2015     // voice setting - signed 8 bit pcm data with CVSD over the air
2016     hci_stack->sco_voice_setting = 0x40;
2017 
2018     hci_state_reset();
2019 }
2020 
2021 /**
2022  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2023  */
2024 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2025     hci_stack->chipset = chipset_driver;
2026 
2027     // reset chipset driver - init is also called on power_up
2028     if (hci_stack->chipset && hci_stack->chipset->init){
2029         hci_stack->chipset->init(hci_stack->config);
2030     }
2031 }
2032 
2033 /**
2034  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2035  */
2036 void hci_set_control(const btstack_control_t *hardware_control){
2037     // references to used control implementation
2038     hci_stack->control = hardware_control;
2039     // init with transport config
2040     hardware_control->init(hci_stack->config);
2041 }
2042 
2043 void hci_close(void){
2044     // close remote device db
2045     if (hci_stack->link_key_db) {
2046         hci_stack->link_key_db->close();
2047     }
2048 
2049     btstack_linked_list_iterator_t lit;
2050     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2051     while (btstack_linked_list_iterator_has_next(&lit)){
2052         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2053         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2054         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2055         hci_shutdown_connection(connection);
2056     }
2057 
2058     hci_power_control(HCI_POWER_OFF);
2059 
2060 #ifdef HAVE_MALLOC
2061     free(hci_stack);
2062 #endif
2063     hci_stack = NULL;
2064 }
2065 
2066 void gap_set_class_of_device(uint32_t class_of_device){
2067     hci_stack->class_of_device = class_of_device;
2068 }
2069 
2070 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2071 void hci_set_bd_addr(bd_addr_t addr){
2072     memcpy(hci_stack->custom_bd_addr, addr, 6);
2073     hci_stack->custom_bd_addr_set = 1;
2074 }
2075 
2076 void hci_disable_l2cap_timeout_check(void){
2077     disable_l2cap_timeouts = 1;
2078 }
2079 // State-Module-Driver overview
2080 // state                    module  low-level
2081 // HCI_STATE_OFF             off      close
2082 // HCI_STATE_INITIALIZING,   on       open
2083 // HCI_STATE_WORKING,        on       open
2084 // HCI_STATE_HALTING,        on       open
2085 // HCI_STATE_SLEEPING,    off/sleep   close
2086 // HCI_STATE_FALLING_ASLEEP  on       open
2087 
2088 static int hci_power_control_on(void){
2089 
2090     // power on
2091     int err = 0;
2092     if (hci_stack->control && hci_stack->control->on){
2093         err = (*hci_stack->control->on)();
2094     }
2095     if (err){
2096         log_error( "POWER_ON failed");
2097         hci_emit_hci_open_failed();
2098         return err;
2099     }
2100 
2101     // int chipset driver
2102     if (hci_stack->chipset && hci_stack->chipset->init){
2103         hci_stack->chipset->init(hci_stack->config);
2104     }
2105 
2106     // init transport
2107     if (hci_stack->hci_transport->init){
2108         hci_stack->hci_transport->init(hci_stack->config);
2109     }
2110 
2111     // open transport
2112     err = hci_stack->hci_transport->open();
2113     if (err){
2114         log_error( "HCI_INIT failed, turning Bluetooth off again");
2115         if (hci_stack->control && hci_stack->control->off){
2116             (*hci_stack->control->off)();
2117         }
2118         hci_emit_hci_open_failed();
2119         return err;
2120     }
2121     return 0;
2122 }
2123 
2124 static void hci_power_control_off(void){
2125 
2126     log_info("hci_power_control_off");
2127 
2128     // close low-level device
2129     hci_stack->hci_transport->close();
2130 
2131     log_info("hci_power_control_off - hci_transport closed");
2132 
2133     // power off
2134     if (hci_stack->control && hci_stack->control->off){
2135         (*hci_stack->control->off)();
2136     }
2137 
2138     log_info("hci_power_control_off - control closed");
2139 
2140     hci_stack->state = HCI_STATE_OFF;
2141 }
2142 
2143 static void hci_power_control_sleep(void){
2144 
2145     log_info("hci_power_control_sleep");
2146 
2147 #if 0
2148     // don't close serial port during sleep
2149 
2150     // close low-level device
2151     hci_stack->hci_transport->close(hci_stack->config);
2152 #endif
2153 
2154     // sleep mode
2155     if (hci_stack->control && hci_stack->control->sleep){
2156         (*hci_stack->control->sleep)();
2157     }
2158 
2159     hci_stack->state = HCI_STATE_SLEEPING;
2160 }
2161 
2162 static int hci_power_control_wake(void){
2163 
2164     log_info("hci_power_control_wake");
2165 
2166     // wake on
2167     if (hci_stack->control && hci_stack->control->wake){
2168         (*hci_stack->control->wake)();
2169     }
2170 
2171 #if 0
2172     // open low-level device
2173     int err = hci_stack->hci_transport->open(hci_stack->config);
2174     if (err){
2175         log_error( "HCI_INIT failed, turning Bluetooth off again");
2176         if (hci_stack->control && hci_stack->control->off){
2177             (*hci_stack->control->off)();
2178         }
2179         hci_emit_hci_open_failed();
2180         return err;
2181     }
2182 #endif
2183 
2184     return 0;
2185 }
2186 
2187 static void hci_power_transition_to_initializing(void){
2188     // set up state machine
2189     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2190     hci_stack->hci_packet_buffer_reserved = 0;
2191     hci_stack->state = HCI_STATE_INITIALIZING;
2192     hci_stack->substate = HCI_INIT_SEND_RESET;
2193 }
2194 
2195 int hci_power_control(HCI_POWER_MODE power_mode){
2196 
2197     log_info("hci_power_control: %u, current mode %u", power_mode, hci_stack->state);
2198 
2199     int err = 0;
2200     switch (hci_stack->state){
2201 
2202         case HCI_STATE_OFF:
2203             switch (power_mode){
2204                 case HCI_POWER_ON:
2205                     err = hci_power_control_on();
2206                     if (err) {
2207                         log_error("hci_power_control_on() error %u", err);
2208                         return err;
2209                     }
2210                     hci_power_transition_to_initializing();
2211                     break;
2212                 case HCI_POWER_OFF:
2213                     // do nothing
2214                     break;
2215                 case HCI_POWER_SLEEP:
2216                     // do nothing (with SLEEP == OFF)
2217                     break;
2218             }
2219             break;
2220 
2221         case HCI_STATE_INITIALIZING:
2222             switch (power_mode){
2223                 case HCI_POWER_ON:
2224                     // do nothing
2225                     break;
2226                 case HCI_POWER_OFF:
2227                     // no connections yet, just turn it off
2228                     hci_power_control_off();
2229                     break;
2230                 case HCI_POWER_SLEEP:
2231                     // no connections yet, just turn it off
2232                     hci_power_control_sleep();
2233                     break;
2234             }
2235             break;
2236 
2237         case HCI_STATE_WORKING:
2238             switch (power_mode){
2239                 case HCI_POWER_ON:
2240                     // do nothing
2241                     break;
2242                 case HCI_POWER_OFF:
2243                     // see hci_run
2244                     hci_stack->state = HCI_STATE_HALTING;
2245                     break;
2246                 case HCI_POWER_SLEEP:
2247                     // see hci_run
2248                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2249                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2250                     break;
2251             }
2252             break;
2253 
2254         case HCI_STATE_HALTING:
2255             switch (power_mode){
2256                 case HCI_POWER_ON:
2257                     hci_power_transition_to_initializing();
2258                     break;
2259                 case HCI_POWER_OFF:
2260                     // do nothing
2261                     break;
2262                 case HCI_POWER_SLEEP:
2263                     // see hci_run
2264                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2265                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2266                     break;
2267             }
2268             break;
2269 
2270         case HCI_STATE_FALLING_ASLEEP:
2271             switch (power_mode){
2272                 case HCI_POWER_ON:
2273 
2274 #ifdef HAVE_PLATFORM_IPHONE_OS
2275                     // nothing to do, if H4 supports power management
2276                     if (btstack_control_iphone_power_management_enabled()){
2277                         hci_stack->state = HCI_STATE_INITIALIZING;
2278                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2279                         break;
2280                     }
2281 #endif
2282                     hci_power_transition_to_initializing();
2283                     break;
2284                 case HCI_POWER_OFF:
2285                     // see hci_run
2286                     hci_stack->state = HCI_STATE_HALTING;
2287                     break;
2288                 case HCI_POWER_SLEEP:
2289                     // do nothing
2290                     break;
2291             }
2292             break;
2293 
2294         case HCI_STATE_SLEEPING:
2295             switch (power_mode){
2296                 case HCI_POWER_ON:
2297 
2298 #ifdef HAVE_PLATFORM_IPHONE_OS
2299                     // nothing to do, if H4 supports power management
2300                     if (btstack_control_iphone_power_management_enabled()){
2301                         hci_stack->state = HCI_STATE_INITIALIZING;
2302                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2303                         hci_update_scan_enable();
2304                         break;
2305                     }
2306 #endif
2307                     err = hci_power_control_wake();
2308                     if (err) return err;
2309                     hci_power_transition_to_initializing();
2310                     break;
2311                 case HCI_POWER_OFF:
2312                     hci_stack->state = HCI_STATE_HALTING;
2313                     break;
2314                 case HCI_POWER_SLEEP:
2315                     // do nothing
2316                     break;
2317             }
2318             break;
2319     }
2320 
2321     // create internal event
2322 	hci_emit_state();
2323 
2324 	// trigger next/first action
2325 	hci_run();
2326 
2327     return 0;
2328 }
2329 
2330 static void hci_update_scan_enable(void){
2331     // 2 = page scan, 1 = inq scan
2332     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2333     hci_run();
2334 }
2335 
2336 void gap_discoverable_control(uint8_t enable){
2337     if (enable) enable = 1; // normalize argument
2338 
2339     if (hci_stack->discoverable == enable){
2340         hci_emit_discoverable_enabled(hci_stack->discoverable);
2341         return;
2342     }
2343 
2344     hci_stack->discoverable = enable;
2345     hci_update_scan_enable();
2346 }
2347 
2348 void gap_connectable_control(uint8_t enable){
2349     if (enable) enable = 1; // normalize argument
2350 
2351     // don't emit event
2352     if (hci_stack->connectable == enable) return;
2353 
2354     hci_stack->connectable = enable;
2355     hci_update_scan_enable();
2356 }
2357 
2358 void gap_local_bd_addr(bd_addr_t address_buffer){
2359     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2360 }
2361 
2362 static void hci_run(void){
2363 
2364     // log_info("hci_run: entered");
2365     btstack_linked_item_t * it;
2366 
2367     // send continuation fragments first, as they block the prepared packet buffer
2368     if (hci_stack->acl_fragmentation_total_size > 0) {
2369         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2370         hci_connection_t *connection = hci_connection_for_handle(con_handle);
2371         if (connection) {
2372             if (hci_can_send_prepared_acl_packet_now(con_handle)){
2373                 hci_send_acl_packet_fragments(connection);
2374                 return;
2375             }
2376         } else {
2377             // connection gone -> discard further fragments
2378             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
2379             hci_stack->acl_fragmentation_total_size = 0;
2380             hci_stack->acl_fragmentation_pos = 0;
2381         }
2382     }
2383 
2384     if (!hci_can_send_command_packet_now()) return;
2385 
2386     // global/non-connection oriented commands
2387 
2388     // decline incoming connections
2389     if (hci_stack->decline_reason){
2390         uint8_t reason = hci_stack->decline_reason;
2391         hci_stack->decline_reason = 0;
2392         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2393         return;
2394     }
2395 
2396     // send scan enable
2397     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2398         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2399         hci_stack->new_scan_enable_value = 0xff;
2400         return;
2401     }
2402 
2403 #ifdef ENABLE_BLE
2404     if (hci_stack->state == HCI_STATE_WORKING){
2405         // handle le scan
2406         switch(hci_stack->le_scanning_state){
2407             case LE_START_SCAN:
2408                 hci_stack->le_scanning_state = LE_SCANNING;
2409                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2410                 return;
2411 
2412             case LE_STOP_SCAN:
2413                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2414                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2415                 return;
2416             default:
2417                 break;
2418         }
2419         if (hci_stack->le_scan_type != 0xff){
2420             // defaults: active scanning, accept all advertisement packets
2421             int scan_type = hci_stack->le_scan_type;
2422             hci_stack->le_scan_type = 0xff;
2423             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);
2424             return;
2425         }
2426         // le advertisement control
2427         if (hci_stack->le_advertisements_todo){
2428             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2429         }
2430         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2431             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2432             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2433             return;
2434         }
2435         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2436             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2437             hci_send_cmd(&hci_le_set_advertising_parameters,
2438                  hci_stack->le_advertisements_interval_min,
2439                  hci_stack->le_advertisements_interval_max,
2440                  hci_stack->le_advertisements_type,
2441                  hci_stack->le_advertisements_own_address_type,
2442                  hci_stack->le_advertisements_direct_address_type,
2443                  hci_stack->le_advertisements_direct_address,
2444                  hci_stack->le_advertisements_channel_map,
2445                  hci_stack->le_advertisements_filter_policy);
2446             return;
2447         }
2448         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2449             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2450             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2451                 hci_stack->le_advertisements_data);
2452             return;
2453         }
2454         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2455             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2456             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2457                 hci_stack->le_scan_response_data);
2458             return;
2459         }
2460         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2461             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2462             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2463             return;
2464         }
2465 
2466         //
2467         // LE Whitelist Management
2468         //
2469 
2470         // check if whitelist needs modification
2471         btstack_linked_list_iterator_t lit;
2472         int modification_pending = 0;
2473         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2474         while (btstack_linked_list_iterator_has_next(&lit)){
2475             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2476             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2477                 modification_pending = 1;
2478                 break;
2479             }
2480         }
2481 
2482         if (modification_pending){
2483             // stop connnecting if modification pending
2484             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2485                 hci_send_cmd(&hci_le_create_connection_cancel);
2486                 return;
2487             }
2488 
2489             // add/remove entries
2490             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2491             while (btstack_linked_list_iterator_has_next(&lit)){
2492                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2493                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2494                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2495                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2496                     return;
2497 
2498                 }
2499                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2500                     bd_addr_t address;
2501                     bd_addr_type_t address_type = entry->address_type;
2502                     memcpy(address, entry->address, 6);
2503                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2504                     btstack_memory_whitelist_entry_free(entry);
2505                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2506                     return;
2507                 }
2508             }
2509         }
2510 
2511         // start connecting
2512         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2513             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2514             bd_addr_t null_addr;
2515             memset(null_addr, 0, 6);
2516             hci_send_cmd(&hci_le_create_connection,
2517                  0x0060,    // scan interval: 60 ms
2518                  0x0030,    // scan interval: 30 ms
2519                  1,         // use whitelist
2520                  0,         // peer address type
2521                  null_addr,      // peer bd addr
2522                  hci_stack->adv_addr_type, // our addr type:
2523                  0x0008,    // conn interval min
2524                  0x0018,    // conn interval max
2525                  0,         // conn latency
2526                  0x0048,    // supervision timeout
2527                  0x0001,    // min ce length
2528                  0x0001     // max ce length
2529                  );
2530             return;
2531         }
2532     }
2533 #endif
2534 
2535     // send pending HCI commands
2536     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2537         hci_connection_t * connection = (hci_connection_t *) it;
2538 
2539         switch(connection->state){
2540             case SEND_CREATE_CONNECTION:
2541                 switch(connection->address_type){
2542                     case BD_ADDR_TYPE_CLASSIC:
2543                         log_info("sending hci_create_connection");
2544                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2545                         break;
2546                     default:
2547 #ifdef ENABLE_BLE
2548                         log_info("sending hci_le_create_connection");
2549                         hci_send_cmd(&hci_le_create_connection,
2550                                      0x0060,    // scan interval: 60 ms
2551                                      0x0030,    // scan interval: 30 ms
2552                                      0,         // don't use whitelist
2553                                      connection->address_type, // peer address type
2554                                      connection->address,      // peer bd addr
2555                                      hci_stack->adv_addr_type, // our addr type:
2556                                      0x0008,    // conn interval min
2557                                      0x0018,    // conn interval max
2558                                      0,         // conn latency
2559                                      0x0048,    // supervision timeout
2560                                      0x0001,    // min ce length
2561                                      0x0001     // max ce length
2562                                      );
2563 
2564                         connection->state = SENT_CREATE_CONNECTION;
2565 #endif
2566                         break;
2567                 }
2568                 return;
2569 
2570             case RECEIVED_CONNECTION_REQUEST:
2571                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2572                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2573                 connection->role  = HCI_ROLE_SLAVE;
2574                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2575                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2576                 }
2577                 return;
2578 
2579 #ifdef ENABLE_BLE
2580             case SEND_CANCEL_CONNECTION:
2581                 connection->state = SENT_CANCEL_CONNECTION;
2582                 hci_send_cmd(&hci_le_create_connection_cancel);
2583                 return;
2584 #endif
2585             case SEND_DISCONNECT:
2586                 connection->state = SENT_DISCONNECT;
2587                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2588                 return;
2589 
2590             default:
2591                 break;
2592         }
2593 
2594         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2595             log_info("responding to link key request");
2596             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2597             link_key_t link_key;
2598             link_key_type_t link_key_type;
2599             if ( hci_stack->link_key_db
2600               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2601               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2602                connection->link_key_type = link_key_type;
2603                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2604             } else {
2605                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2606             }
2607             return;
2608         }
2609 
2610         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2611             log_info("denying to pin request");
2612             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2613             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2614             return;
2615         }
2616 
2617         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2618             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2619             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2620             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2621                 // tweak authentication requirements
2622                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2623                 if (connection->bonding_flags & BONDING_DEDICATED){
2624                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2625                 }
2626                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2627                     authreq |= 1;
2628                 }
2629                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2630             } else {
2631                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2632             }
2633             return;
2634         }
2635 
2636         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2637             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2638             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2639             return;
2640         }
2641 
2642         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2643             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2644             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2645             return;
2646         }
2647 
2648         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2649             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2650             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2651             return;
2652         }
2653 
2654         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2655             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2656             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2657             return;
2658         }
2659         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2660             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2661             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2662             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2663             return;
2664         }
2665         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2666             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2667             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2668             return;
2669         }
2670         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2671             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2672             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2673             return;
2674         }
2675 
2676 #ifdef ENABLE_BLE
2677         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2678             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2679 
2680             uint16_t connection_interval_min = connection->le_conn_interval_min;
2681             connection->le_conn_interval_min = 0;
2682             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2683                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2684                 0x0000, 0xffff);
2685         }
2686 #endif
2687     }
2688 
2689     hci_connection_t * connection;
2690     switch (hci_stack->state){
2691         case HCI_STATE_INITIALIZING:
2692             hci_initializing_run();
2693             break;
2694 
2695         case HCI_STATE_HALTING:
2696 
2697             log_info("HCI_STATE_HALTING");
2698 
2699             // free whitelist entries
2700 #ifdef ENABLE_BLE
2701             {
2702                 btstack_linked_list_iterator_t lit;
2703                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2704                 while (btstack_linked_list_iterator_has_next(&lit)){
2705                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2706                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2707                     btstack_memory_whitelist_entry_free(entry);
2708                 }
2709             }
2710 #endif
2711             // close all open connections
2712             connection =  (hci_connection_t *) hci_stack->connections;
2713             if (connection){
2714                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2715                 if (!hci_can_send_command_packet_now()) return;
2716 
2717                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2718 
2719                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2720                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2721 
2722                 // ... which would be ignored anyway as we shutdown (free) the connection now
2723                 hci_shutdown_connection(connection);
2724 
2725                 // finally, send the disconnect command
2726                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2727                 return;
2728             }
2729             log_info("HCI_STATE_HALTING, calling off");
2730 
2731             // switch mode
2732             hci_power_control_off();
2733 
2734             log_info("HCI_STATE_HALTING, emitting state");
2735             hci_emit_state();
2736             log_info("HCI_STATE_HALTING, done");
2737             break;
2738 
2739         case HCI_STATE_FALLING_ASLEEP:
2740             switch(hci_stack->substate) {
2741                 case HCI_FALLING_ASLEEP_DISCONNECT:
2742                     log_info("HCI_STATE_FALLING_ASLEEP");
2743                     // close all open connections
2744                     connection =  (hci_connection_t *) hci_stack->connections;
2745 
2746 #ifdef HAVE_PLATFORM_IPHONE_OS
2747                     // don't close connections, if H4 supports power management
2748                     if (btstack_control_iphone_power_management_enabled()){
2749                         connection = NULL;
2750                     }
2751 #endif
2752                     if (connection){
2753 
2754                         // send disconnect
2755                         if (!hci_can_send_command_packet_now()) return;
2756 
2757                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2758                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2759 
2760                         // send disconnected event right away - causes higher layer connections to get closed, too.
2761                         hci_shutdown_connection(connection);
2762                         return;
2763                     }
2764 
2765                     if (hci_classic_supported()){
2766                         // disable page and inquiry scan
2767                         if (!hci_can_send_command_packet_now()) return;
2768 
2769                         log_info("HCI_STATE_HALTING, disabling inq scans");
2770                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2771 
2772                         // continue in next sub state
2773                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2774                         break;
2775                     }
2776                     // fall through for ble-only chips
2777 
2778                 case HCI_FALLING_ASLEEP_COMPLETE:
2779                     log_info("HCI_STATE_HALTING, calling sleep");
2780 #ifdef HAVE_PLATFORM_IPHONE_OS
2781                     // don't actually go to sleep, if H4 supports power management
2782                     if (btstack_control_iphone_power_management_enabled()){
2783                         // SLEEP MODE reached
2784                         hci_stack->state = HCI_STATE_SLEEPING;
2785                         hci_emit_state();
2786                         break;
2787                     }
2788 #endif
2789                     // switch mode
2790                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2791                     hci_emit_state();
2792                     break;
2793 
2794                 default:
2795                     break;
2796             }
2797             break;
2798 
2799         default:
2800             break;
2801     }
2802 }
2803 
2804 int hci_send_cmd_packet(uint8_t *packet, int size){
2805     bd_addr_t addr;
2806     hci_connection_t * conn;
2807     // house-keeping
2808 
2809     // create_connection?
2810     if (IS_COMMAND(packet, hci_create_connection)){
2811         reverse_bd_addr(&packet[3], addr);
2812         log_info("Create_connection to %s", bd_addr_to_str(addr));
2813 
2814         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2815         if (!conn){
2816             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2817             if (!conn){
2818                 // notify client that alloc failed
2819                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
2820                 return 0; // don't sent packet to controller
2821             }
2822             conn->state = SEND_CREATE_CONNECTION;
2823         }
2824         log_info("conn state %u", conn->state);
2825         switch (conn->state){
2826             // if connection active exists
2827             case OPEN:
2828                 // and OPEN, emit connection complete command, don't send to controller
2829                 hci_emit_connection_complete(addr, conn->con_handle, 0);
2830                 return 0;
2831             case SEND_CREATE_CONNECTION:
2832                 // connection created by hci, e.g. dedicated bonding
2833                 break;
2834             default:
2835                 // otherwise, just ignore as it is already in the open process
2836                 return 0;
2837         }
2838         conn->state = SENT_CREATE_CONNECTION;
2839     }
2840     if (IS_COMMAND(packet, hci_link_key_request_reply)){
2841         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
2842     }
2843     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
2844         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
2845     }
2846 
2847     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
2848         if (hci_stack->link_key_db){
2849             reverse_bd_addr(&packet[3], addr);
2850             hci_stack->link_key_db->delete_link_key(addr);
2851         }
2852     }
2853 
2854     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
2855     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
2856         reverse_bd_addr(&packet[3], addr);
2857         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2858         if (conn){
2859             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
2860         }
2861     }
2862 
2863     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
2864     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
2865     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
2866     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
2867         reverse_bd_addr(&packet[3], addr);
2868         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2869         if (conn){
2870             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
2871         }
2872     }
2873 
2874     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2875         hci_stack->loopback_mode = packet[3];
2876     }
2877 
2878 #ifdef ENABLE_BLE
2879     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
2880         hci_stack->adv_addr_type = packet[8];
2881     }
2882     if (IS_COMMAND(packet, hci_le_set_random_address)){
2883         reverse_bd_addr(&packet[3], hci_stack->adv_address);
2884     }
2885     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
2886         hci_stack->le_advertisements_active = packet[3];
2887     }
2888     if (IS_COMMAND(packet, hci_le_create_connection)){
2889         // white list used?
2890         uint8_t initiator_filter_policy = packet[7];
2891         switch (initiator_filter_policy){
2892             case 0:
2893                 // whitelist not used
2894                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
2895                 break;
2896             case 1:
2897                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
2898                 break;
2899             default:
2900                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
2901                 break;
2902         }
2903     }
2904     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
2905         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2906     }
2907 #endif
2908 
2909     hci_stack->num_cmd_packets--;
2910 
2911     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2912     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2913 
2914     // release packet buffer for synchronous transport implementations
2915     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
2916         hci_stack->hci_packet_buffer_reserved = 0;
2917     }
2918 
2919     return err;
2920 }
2921 
2922 // disconnect because of security block
2923 void hci_disconnect_security_block(hci_con_handle_t con_handle){
2924     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2925     if (!connection) return;
2926     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2927 }
2928 
2929 
2930 // Configure Secure Simple Pairing
2931 
2932 // enable will enable SSP during init
2933 void gap_ssp_set_enable(int enable){
2934     hci_stack->ssp_enable = enable;
2935 }
2936 
2937 static int hci_local_ssp_activated(void){
2938     return gap_ssp_supported() && hci_stack->ssp_enable;
2939 }
2940 
2941 // if set, BTstack will respond to io capability request using authentication requirement
2942 void gap_ssp_set_io_capability(int io_capability){
2943     hci_stack->ssp_io_capability = io_capability;
2944 }
2945 void gap_ssp_set_authentication_requirement(int authentication_requirement){
2946     hci_stack->ssp_authentication_requirement = authentication_requirement;
2947 }
2948 
2949 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
2950 void gap_ssp_set_auto_accept(int auto_accept){
2951     hci_stack->ssp_auto_accept = auto_accept;
2952 }
2953 
2954 /**
2955  * pre: numcmds >= 0 - it's allowed to send a command to the controller
2956  */
2957 int hci_send_cmd(const hci_cmd_t *cmd, ...){
2958 
2959     if (!hci_can_send_command_packet_now()){
2960         log_error("hci_send_cmd called but cannot send packet now");
2961         return 0;
2962     }
2963 
2964     // for HCI INITIALIZATION
2965     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
2966     hci_stack->last_cmd_opcode = cmd->opcode;
2967 
2968     hci_reserve_packet_buffer();
2969     uint8_t * packet = hci_stack->hci_packet_buffer;
2970 
2971     va_list argptr;
2972     va_start(argptr, cmd);
2973     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
2974     va_end(argptr);
2975 
2976     return hci_send_cmd_packet(packet, size);
2977 }
2978 
2979 // Create various non-HCI events.
2980 // TODO: generalize, use table similar to hci_create_command
2981 
2982 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
2983     // dump packet
2984     if (dump) {
2985         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
2986     }
2987 
2988     // dispatch to all event handlers
2989     btstack_linked_list_iterator_t it;
2990     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
2991     while (btstack_linked_list_iterator_has_next(&it)){
2992         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
2993         entry->callback(HCI_EVENT_PACKET, 0, event, size);
2994     }
2995 }
2996 
2997 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
2998     if (!hci_stack->acl_packet_handler) return;
2999     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3000 }
3001 
3002 static void hci_notify_if_sco_can_send_now(void){
3003     // notify SCO sender if waiting
3004     if (!hci_stack->sco_waiting_for_can_send_now) return;
3005     if (hci_can_send_sco_packet_now()){
3006         hci_stack->sco_waiting_for_can_send_now = 0;
3007         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3008         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3009         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3010     }
3011 }
3012 
3013 void hci_emit_state(void){
3014     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3015     uint8_t event[3];
3016     event[0] = BTSTACK_EVENT_STATE;
3017     event[1] = sizeof(event) - 2;
3018     event[2] = hci_stack->state;
3019     hci_emit_event(event, sizeof(event), 1);
3020 }
3021 
3022 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3023     uint8_t event[13];
3024     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3025     event[1] = sizeof(event) - 2;
3026     event[2] = status;
3027     little_endian_store_16(event, 3, con_handle);
3028     reverse_bd_addr(address, &event[5]);
3029     event[11] = 1; // ACL connection
3030     event[12] = 0; // encryption disabled
3031     hci_emit_event(event, sizeof(event), 1);
3032 }
3033 
3034 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3035     uint8_t event[21];
3036     event[0] = HCI_EVENT_LE_META;
3037     event[1] = sizeof(event) - 2;
3038     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3039     event[3] = status;
3040     little_endian_store_16(event, 4, con_handle);
3041     event[6] = 0; // TODO: role
3042     event[7] = address_type;
3043     reverse_bd_addr(address, &event[8]);
3044     little_endian_store_16(event, 14, 0); // interval
3045     little_endian_store_16(event, 16, 0); // latency
3046     little_endian_store_16(event, 18, 0); // supervision timeout
3047     event[20] = 0; // master clock accuracy
3048     hci_emit_event(event, sizeof(event), 1);
3049 }
3050 
3051 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3052     uint8_t event[6];
3053     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3054     event[1] = sizeof(event) - 2;
3055     event[2] = 0; // status = OK
3056     little_endian_store_16(event, 3, con_handle);
3057     event[5] = reason;
3058     hci_emit_event(event, sizeof(event), 1);
3059 }
3060 
3061 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3062     if (disable_l2cap_timeouts) return;
3063     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3064     uint8_t event[4];
3065     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3066     event[1] = sizeof(event) - 2;
3067     little_endian_store_16(event, 2, conn->con_handle);
3068     hci_emit_event(event, sizeof(event), 1);
3069 }
3070 
3071 static void hci_emit_nr_connections_changed(void){
3072     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3073     uint8_t event[3];
3074     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3075     event[1] = sizeof(event) - 2;
3076     event[2] = nr_hci_connections();
3077     hci_emit_event(event, sizeof(event), 1);
3078 }
3079 
3080 static void hci_emit_hci_open_failed(void){
3081     log_info("BTSTACK_EVENT_POWERON_FAILED");
3082     uint8_t event[2];
3083     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3084     event[1] = sizeof(event) - 2;
3085     hci_emit_event(event, sizeof(event), 1);
3086 }
3087 
3088 static void hci_emit_discoverable_enabled(uint8_t enabled){
3089     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3090     uint8_t event[3];
3091     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3092     event[1] = sizeof(event) - 2;
3093     event[2] = enabled;
3094     hci_emit_event(event, sizeof(event), 1);
3095 }
3096 
3097 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3098     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3099     uint8_t event[5];
3100     int pos = 0;
3101     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3102     event[pos++] = sizeof(event) - 2;
3103     little_endian_store_16(event, 2, con_handle);
3104     pos += 2;
3105     event[pos++] = level;
3106     hci_emit_event(event, sizeof(event), 1);
3107 }
3108 
3109 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3110     log_info("hci_emit_dedicated_bonding_result %u ", status);
3111     uint8_t event[9];
3112     int pos = 0;
3113     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3114     event[pos++] = sizeof(event) - 2;
3115     event[pos++] = status;
3116     reverse_bd_addr(address, &event[pos]);
3117     hci_emit_event(event, sizeof(event), 1);
3118 }
3119 
3120 // query if remote side supports eSCO
3121 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3122     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3123     if (!connection) return 0;
3124     return connection->remote_supported_feature_eSCO;
3125 }
3126 
3127 // query if remote side supports SSP
3128 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3129     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3130     if (!connection) return 0;
3131     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3132 }
3133 
3134 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3135     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3136 }
3137 
3138 // GAP API
3139 /**
3140  * @bbrief enable/disable bonding. default is enabled
3141  * @praram enabled
3142  */
3143 void gap_set_bondable_mode(int enable){
3144     hci_stack->bondable = enable ? 1 : 0;
3145 }
3146 /**
3147  * @brief Get bondable mode.
3148  * @return 1 if bondable
3149  */
3150 int gap_get_bondable_mode(void){
3151     return hci_stack->bondable;
3152 }
3153 
3154 /**
3155  * @brief map link keys to security levels
3156  */
3157 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3158     switch (link_key_type){
3159         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3160             return LEVEL_4;
3161         case COMBINATION_KEY:
3162         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3163             return LEVEL_3;
3164         default:
3165             return LEVEL_2;
3166     }
3167 }
3168 
3169 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3170     if (!connection) return LEVEL_0;
3171     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3172     return gap_security_level_for_link_key_type(connection->link_key_type);
3173 }
3174 
3175 
3176 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3177     log_info("gap_mitm_protection_required_for_security_level %u", level);
3178     return level > LEVEL_2;
3179 }
3180 
3181 /**
3182  * @brief get current security level
3183  */
3184 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3185     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3186     if (!connection) return LEVEL_0;
3187     return gap_security_level_for_connection(connection);
3188 }
3189 
3190 /**
3191  * @brief request connection to device to
3192  * @result GAP_AUTHENTICATION_RESULT
3193  */
3194 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3195     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3196     if (!connection){
3197         hci_emit_security_level(con_handle, LEVEL_0);
3198         return;
3199     }
3200     gap_security_level_t current_level = gap_security_level(con_handle);
3201     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3202     if (current_level >= requested_level){
3203         hci_emit_security_level(con_handle, current_level);
3204         return;
3205     }
3206 
3207     connection->requested_security_level = requested_level;
3208 
3209 #if 0
3210     // sending encryption request without a link key results in an error.
3211     // TODO: figure out how to use it properly
3212 
3213     // would enabling ecnryption suffice (>= LEVEL_2)?
3214     if (hci_stack->link_key_db){
3215         link_key_type_t link_key_type;
3216         link_key_t      link_key;
3217         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3218             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3219                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3220                 return;
3221             }
3222         }
3223     }
3224 #endif
3225 
3226     // try to authenticate connection
3227     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3228     hci_run();
3229 }
3230 
3231 /**
3232  * @brief start dedicated bonding with device. disconnect after bonding
3233  * @param device
3234  * @param request MITM protection
3235  * @result GAP_DEDICATED_BONDING_COMPLETE
3236  */
3237 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3238 
3239     // create connection state machine
3240     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3241 
3242     if (!connection){
3243         return BTSTACK_MEMORY_ALLOC_FAILED;
3244     }
3245 
3246     // delete linkn key
3247     gap_drop_link_key_for_bd_addr(device);
3248 
3249     // configure LEVEL_2/3, dedicated bonding
3250     connection->state = SEND_CREATE_CONNECTION;
3251     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3252     log_info("gap_dedicated_bonding, mitm %u -> level %u", mitm_protection_required, connection->requested_security_level);
3253     connection->bonding_flags = BONDING_DEDICATED;
3254 
3255     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3256 
3257     // handle: connnection failure (connection complete != ok)
3258     // handle: authentication failure
3259     // handle: disconnect on done
3260 
3261     hci_run();
3262 
3263     return 0;
3264 }
3265 
3266 void gap_set_local_name(const char * local_name){
3267     hci_stack->local_name = local_name;
3268 }
3269 
3270 void gap_start_scan(void){
3271     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3272     hci_stack->le_scanning_state = LE_START_SCAN;
3273     hci_run();
3274 }
3275 
3276 void gap_stop_scan(void){
3277     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3278     hci_stack->le_scanning_state = LE_STOP_SCAN;
3279     hci_run();
3280 }
3281 
3282 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3283     hci_stack->le_scan_type     = scan_type;
3284     hci_stack->le_scan_interval = scan_interval;
3285     hci_stack->le_scan_window   = scan_window;
3286     hci_run();
3287 }
3288 
3289 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3290     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3291     if (!conn){
3292         log_info("gap_connect: no connection exists yet, creating context");
3293         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3294         if (!conn){
3295             // notify client that alloc failed
3296             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3297             log_info("gap_connect: failed to alloc hci_connection_t");
3298             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3299         }
3300         conn->state = SEND_CREATE_CONNECTION;
3301         log_info("gap_connect: send create connection next");
3302         hci_run();
3303         return 0;
3304     }
3305 
3306     if (!hci_is_le_connection(conn) ||
3307         conn->state == SEND_CREATE_CONNECTION ||
3308         conn->state == SENT_CREATE_CONNECTION) {
3309         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3310         log_error("gap_connect: classic connection or connect is already being created");
3311         return GATT_CLIENT_IN_WRONG_STATE;
3312     }
3313 
3314     log_info("gap_connect: context exists with state %u", conn->state);
3315     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3316     hci_run();
3317     return 0;
3318 }
3319 
3320 // @assumption: only a single outgoing LE Connection exists
3321 static hci_connection_t * gap_get_outgoing_connection(void){
3322     btstack_linked_item_t *it;
3323     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3324         hci_connection_t * conn = (hci_connection_t *) it;
3325         if (!hci_is_le_connection(conn)) continue;
3326         switch (conn->state){
3327             case SEND_CREATE_CONNECTION:
3328             case SENT_CREATE_CONNECTION:
3329                 return conn;
3330             default:
3331                 break;
3332         };
3333     }
3334     return NULL;
3335 }
3336 
3337 uint8_t gap_connect_cancel(void){
3338     hci_connection_t * conn = gap_get_outgoing_connection();
3339     if (!conn) return 0;
3340     switch (conn->state){
3341         case SEND_CREATE_CONNECTION:
3342             // skip sending create connection and emit event instead
3343             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3344             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3345             btstack_memory_hci_connection_free( conn );
3346             break;
3347         case SENT_CREATE_CONNECTION:
3348             // request to send cancel connection
3349             conn->state = SEND_CANCEL_CONNECTION;
3350             hci_run();
3351             break;
3352         default:
3353             break;
3354     }
3355     return 0;
3356 }
3357 
3358 /**
3359  * @brief Updates the connection parameters for a given LE connection
3360  * @param handle
3361  * @param conn_interval_min (unit: 1.25ms)
3362  * @param conn_interval_max (unit: 1.25ms)
3363  * @param conn_latency
3364  * @param supervision_timeout (unit: 10ms)
3365  * @returns 0 if ok
3366  */
3367 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3368     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3369     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3370     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3371     connection->le_conn_interval_min = conn_interval_min;
3372     connection->le_conn_interval_max = conn_interval_max;
3373     connection->le_conn_latency = conn_latency;
3374     connection->le_supervision_timeout = supervision_timeout;
3375     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3376     hci_run();
3377     return 0;
3378 }
3379 
3380 /**
3381  * @brief Request an update of the connection parameter for a given LE connection
3382  * @param handle
3383  * @param conn_interval_min (unit: 1.25ms)
3384  * @param conn_interval_max (unit: 1.25ms)
3385  * @param conn_latency
3386  * @param supervision_timeout (unit: 10ms)
3387  * @returns 0 if ok
3388  */
3389 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3390     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3391     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3392     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3393     connection->le_conn_interval_min = conn_interval_min;
3394     connection->le_conn_interval_max = conn_interval_max;
3395     connection->le_conn_latency = conn_latency;
3396     connection->le_supervision_timeout = supervision_timeout;
3397     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3398     hci_run();
3399     return 0;
3400 }
3401 
3402 static void gap_advertisments_changed(void){
3403     // disable advertisements before updating adv, scan data, or adv params
3404     if (hci_stack->le_advertisements_active){
3405         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3406     }
3407     hci_run();
3408 }
3409 
3410 /**
3411  * @brief Set Advertisement Data
3412  * @param advertising_data_length
3413  * @param advertising_data (max 31 octets)
3414  * @note data is not copied, pointer has to stay valid
3415  */
3416 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3417     hci_stack->le_advertisements_data_len = advertising_data_length;
3418     hci_stack->le_advertisements_data = advertising_data;
3419     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3420     gap_advertisments_changed();
3421 }
3422 
3423 /**
3424  * @brief Set Scan Response Data
3425  * @param advertising_data_length
3426  * @param advertising_data (max 31 octets)
3427  * @note data is not copied, pointer has to stay valid
3428  */
3429 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3430     hci_stack->le_scan_response_data_len = scan_response_data_length;
3431     hci_stack->le_scan_response_data = scan_response_data;
3432     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3433     gap_advertisments_changed();
3434 }
3435 
3436 /**
3437  * @brief Set Advertisement Parameters
3438  * @param adv_int_min
3439  * @param adv_int_max
3440  * @param adv_type
3441  * @param own_address_type
3442  * @param direct_address_type
3443  * @param direct_address
3444  * @param channel_map
3445  * @param filter_policy
3446  *
3447  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3448  */
3449  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3450     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3451     uint8_t channel_map, uint8_t filter_policy) {
3452 
3453     hci_stack->le_advertisements_interval_min = adv_int_min;
3454     hci_stack->le_advertisements_interval_max = adv_int_max;
3455     hci_stack->le_advertisements_type = adv_type;
3456     hci_stack->le_advertisements_own_address_type = own_address_type;
3457     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3458     hci_stack->le_advertisements_channel_map = channel_map;
3459     hci_stack->le_advertisements_filter_policy = filter_policy;
3460     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3461 
3462     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3463     gap_advertisments_changed();
3464  }
3465 
3466 /**
3467  * @brief Enable/Disable Advertisements
3468  * @param enabled
3469  */
3470 void gap_advertisements_enable(int enabled){
3471     hci_stack->le_advertisements_enabled = enabled;
3472     if (enabled && !hci_stack->le_advertisements_active){
3473         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3474     }
3475     if (!enabled && hci_stack->le_advertisements_active){
3476         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3477     }
3478     hci_run();
3479 }
3480 
3481 
3482 uint8_t gap_disconnect(hci_con_handle_t handle){
3483     hci_connection_t * conn = hci_connection_for_handle(handle);
3484     if (!conn){
3485         hci_emit_disconnection_complete(handle, 0);
3486         return 0;
3487     }
3488     conn->state = SEND_DISCONNECT;
3489     hci_run();
3490     return 0;
3491 }
3492 
3493 /**
3494  * @brief Get connection type
3495  * @param con_handle
3496  * @result connection_type
3497  */
3498 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3499     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3500     if (!conn) return GAP_CONNECTION_INVALID;
3501     switch (conn->address_type){
3502         case BD_ADDR_TYPE_LE_PUBLIC:
3503         case BD_ADDR_TYPE_LE_RANDOM:
3504             return GAP_CONNECTION_LE;
3505         case BD_ADDR_TYPE_SCO:
3506             return GAP_CONNECTION_SCO;
3507         case BD_ADDR_TYPE_CLASSIC:
3508             return GAP_CONNECTION_ACL;
3509         default:
3510             return GAP_CONNECTION_INVALID;
3511     }
3512 }
3513 
3514 #ifdef ENABLE_BLE
3515 
3516 /**
3517  * @brief Auto Connection Establishment - Start Connecting to device
3518  * @param address_typ
3519  * @param address
3520  * @returns 0 if ok
3521  */
3522 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3523     // check capacity
3524     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3525     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3526     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3527     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3528     entry->address_type = address_type;
3529     memcpy(entry->address, address, 6);
3530     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3531     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3532     hci_run();
3533     return 0;
3534 }
3535 
3536 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3537     btstack_linked_list_iterator_t it;
3538     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3539     while (btstack_linked_list_iterator_has_next(&it)){
3540         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3541         if (entry->address_type != address_type) continue;
3542         if (memcmp(entry->address, address, 6) != 0) continue;
3543         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3544             // remove from controller if already present
3545             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3546             continue;
3547         }
3548         // direclty remove entry from whitelist
3549         btstack_linked_list_iterator_remove(&it);
3550         btstack_memory_whitelist_entry_free(entry);
3551     }
3552 }
3553 
3554 /**
3555  * @brief Auto Connection Establishment - Stop Connecting to device
3556  * @param address_typ
3557  * @param address
3558  * @returns 0 if ok
3559  */
3560 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3561     hci_remove_from_whitelist(address_type, address);
3562     hci_run();
3563     return 0;
3564 }
3565 
3566 /**
3567  * @brief Auto Connection Establishment - Stop everything
3568  * @note  Convenience function to stop all active auto connection attempts
3569  */
3570 void gap_auto_connection_stop_all(void){
3571     btstack_linked_list_iterator_t it;
3572     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3573     while (btstack_linked_list_iterator_has_next(&it)){
3574         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3575         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3576             // remove from controller if already present
3577             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3578             continue;
3579         }
3580         // directly remove entry from whitelist
3581         btstack_linked_list_iterator_remove(&it);
3582         btstack_memory_whitelist_entry_free(entry);
3583     }
3584     hci_run();
3585 }
3586 
3587 #endif
3588 
3589 /**
3590  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3591  */
3592 void hci_set_sco_voice_setting(uint16_t voice_setting){
3593     hci_stack->sco_voice_setting = voice_setting;
3594 }
3595 
3596 /**
3597  * @brief Get SCO Voice Setting
3598  * @return current voice setting
3599  */
3600 uint16_t hci_get_sco_voice_setting(void){
3601     return hci_stack->sco_voice_setting;
3602 }
3603 
3604 /** @brief Get SCO packet length for current SCO Voice setting
3605  *  @note  Using SCO packets of the exact length is required for USB transfer
3606  *  @return Length of SCO packets in bytes (not audio frames)
3607  */
3608 int hci_get_sco_packet_length(void){
3609     // see Core Spec for H2 USB Transfer.
3610     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3611     return 27;
3612 }
3613 
3614 /**
3615  * @brief Set callback for Bluetooth Hardware Error
3616  */
3617 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
3618     hci_stack->hardware_error_callback = fn;
3619 }
3620 
3621 /**
3622  * @brief Set callback for local information from Bluetooth controller right after HCI Reset
3623  * @note Can be used to select chipset driver dynamically during startup
3624  */
3625 void hci_set_local_version_information_callback(void (*fn)(uint8_t * local_version_information)){
3626     hci_stack->local_version_information_callback = fn;
3627 }
3628 
3629 void hci_disconnect_all(void){
3630     btstack_linked_list_iterator_t it;
3631     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3632     while (btstack_linked_list_iterator_has_next(&it)){
3633         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3634         if (con->state == SENT_DISCONNECT) continue;
3635         con->state = SEND_DISCONNECT;
3636     }
3637     hci_run();
3638 }
3639