xref: /btstack/src/hci.c (revision c2e1fa600562f8d5d28591236dae7ac2cd0511d0)
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_non_flushable_packet_boundary_flag_supported(void){
797     // No. 54, byte 6, bit 6
798     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
799 }
800 
801 static int gap_ssp_supported(void){
802     // No. 51, byte 6, bit 3
803     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
804 }
805 
806 static int hci_classic_supported(void){
807     // No. 37, byte 4, bit 5, = No BR/EDR Support
808     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
809 }
810 
811 static int hci_le_supported(void){
812 #ifdef ENABLE_BLE
813     // No. 37, byte 4, bit 6 = LE Supported (Controller)
814     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
815 #else
816     return 0;
817 #endif
818 }
819 
820 // get addr type and address used in advertisement packets
821 void gap_advertisements_get_address(uint8_t * addr_type, bd_addr_t  addr){
822     *addr_type = hci_stack->adv_addr_type;
823     if (hci_stack->adv_addr_type){
824         memcpy(addr, hci_stack->adv_address, 6);
825     } else {
826         memcpy(addr, hci_stack->local_bd_addr, 6);
827     }
828 }
829 
830 #ifdef ENABLE_BLE
831 void le_handle_advertisement_report(uint8_t *packet, int size){
832     int offset = 3;
833     int num_reports = packet[offset];
834     offset += 1;
835 
836     int i;
837     // log_info("HCI: handle adv report with num reports: %d", num_reports);
838     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
839     for (i=0; i<num_reports;i++){
840         uint8_t data_length = packet[offset + 8];
841         uint8_t event_size = 10 + data_length;
842         int pos = 0;
843         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
844         event[pos++] = event_size;
845         memcpy(&event[pos], &packet[offset], 1+1+6); // event type + address type + address
846         offset += 8;
847         pos += 8;
848         event[pos++] = packet[offset + 1 + data_length]; // rssi
849         event[pos++] = packet[offset++]; //data_length;
850         memcpy(&event[pos], &packet[offset], data_length);
851         pos += data_length;
852         offset += data_length + 1; // rssi
853         hci_emit_event(event, pos, 1);
854     }
855 }
856 #endif
857 
858 static uint32_t hci_transport_uart_get_main_baud_rate(void){
859     if (!hci_stack->config) return 0;
860     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
861     // Limit baud rate for Broadcom chipsets to 3 mbps
862     if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION && baud_rate > 3000000){
863         baud_rate = 3000000;
864     }
865     return baud_rate;
866 }
867 
868 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
869     switch (hci_stack->substate){
870         case HCI_INIT_W4_SEND_RESET:
871             log_info("Resend HCI Reset");
872             hci_stack->substate = HCI_INIT_SEND_RESET;
873             hci_stack->num_cmd_packets = 1;
874             hci_run();
875             break;
876         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
877             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
878             if (hci_stack->hci_transport->reset_link){
879                 hci_stack->hci_transport->reset_link();
880             }
881             // NOTE: explicit fallthrough to HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT
882         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
883             log_info("Resend HCI Reset - CSR Warm Boot");
884             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
885             hci_stack->num_cmd_packets = 1;
886             hci_run();
887             break;
888         case HCI_INIT_W4_SEND_BAUD_CHANGE:
889             if (hci_stack->hci_transport->set_baudrate){
890                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
891                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
892                 hci_stack->hci_transport->set_baudrate(baud_rate);
893             }
894             // For CSR, HCI Reset is sent on new baud rate
895             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
896                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
897                 hci_run();
898             }
899             break;
900         default:
901             break;
902     }
903 }
904 
905 static void hci_initializing_next_state(void){
906     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
907 }
908 
909 // assumption: hci_can_send_command_packet_now() == true
910 static void hci_initializing_run(void){
911     log_info("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
912     switch (hci_stack->substate){
913         case HCI_INIT_SEND_RESET:
914             hci_state_reset();
915 
916 #ifndef HAVE_PLATFORM_IPHONE_OS
917             // prepare reset if command complete not received in 100ms
918             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
919             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
920             btstack_run_loop_add_timer(&hci_stack->timeout);
921 #endif
922             // send command
923             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
924             hci_send_cmd(&hci_reset);
925             break;
926         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
927             hci_send_cmd(&hci_read_local_version_information);
928             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
929             break;
930         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
931             hci_state_reset();
932             // prepare reset if command complete not received in 100ms
933             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
934             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
935             btstack_run_loop_add_timer(&hci_stack->timeout);
936             // send command
937             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
938             hci_send_cmd(&hci_reset);
939             break;
940         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
941             hci_state_reset();
942             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
943             hci_send_cmd(&hci_reset);
944             break;
945         case HCI_INIT_SEND_BAUD_CHANGE: {
946             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
947             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
948             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
949             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
950             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
951             // STLC25000D: baudrate change happens within 0.5 s after command was send,
952             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
953             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
954                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
955                 btstack_run_loop_add_timer(&hci_stack->timeout);
956             }
957             break;
958         }
959         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
960             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
961             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
962             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
963             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
964             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
965             break;
966         }
967         case HCI_INIT_CUSTOM_INIT:
968             log_info("Custom init");
969             // Custom initialization
970             if (hci_stack->chipset && hci_stack->chipset->next_command){
971                 int valid_cmd = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
972                 if (valid_cmd){
973                     int size = 3 + hci_stack->hci_packet_buffer[2];
974                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
975                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
976                     switch (valid_cmd) {
977                         case 1:
978                         default:
979                             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
980                             break;
981                         case 2: // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
982                             log_info("CSR Warm Boot");
983                             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
984                             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
985                             btstack_run_loop_add_timer(&hci_stack->timeout);
986                             if (hci_stack->manufacturer == COMPANY_ID_CAMBRIDGE_SILICON_RADIO
987                                 && hci_stack->config
988                                 && hci_stack->chipset
989                                 // && hci_stack->chipset->set_baudrate_command -- there's no such command
990                                 && hci_stack->hci_transport->set_baudrate
991                                 && hci_transport_uart_get_main_baud_rate()){
992                                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
993                             } else {
994                                hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
995                             }
996                             break;
997                     }
998                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
999                     break;
1000                 }
1001                 log_info("hci_run: init script done");
1002 
1003                 // Init script download causes baud rate to reset on Broadcom chipsets, restore UART baud rate if needed
1004                 if (hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1005                     int need_baud_change = hci_stack->config
1006                         && hci_stack->chipset
1007                         && hci_stack->chipset->set_baudrate_command
1008                         && hci_stack->hci_transport->set_baudrate
1009                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1010                     if (need_baud_change) {
1011                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1012                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1013                         hci_stack->hci_transport->set_baudrate(baud_rate);
1014                     }
1015                 }
1016             }
1017             // otherwise continue
1018             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1019             hci_send_cmd(&hci_read_local_supported_commands);
1020             break;
1021         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1022             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
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_SET_BD_ADDR:
1027             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1028             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1029             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1030             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1031             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1032             break;
1033         case HCI_INIT_READ_BD_ADDR:
1034             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1035             hci_send_cmd(&hci_read_bd_addr);
1036             break;
1037         case HCI_INIT_READ_BUFFER_SIZE:
1038             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1039             hci_send_cmd(&hci_read_buffer_size);
1040             break;
1041         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1042             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1043             hci_send_cmd(&hci_read_local_supported_features);
1044             break;
1045         case HCI_INIT_SET_EVENT_MASK:
1046             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1047             if (hci_le_supported()){
1048                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1049             } else {
1050                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1051                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1052             }
1053             break;
1054         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1055             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1056             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1057             break;
1058         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1059             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1060             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1061             break;
1062         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1063             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1064             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1065             break;
1066         case HCI_INIT_WRITE_LOCAL_NAME:
1067             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1068             if (hci_stack->local_name){
1069                 hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1070             } else {
1071                 char local_name[8+17+1];
1072                 // BTstack 11:22:33:44:55:66
1073                 memcpy(local_name, "BTstack ", 8);
1074                 memcpy(&local_name[8], bd_addr_to_str(hci_stack->local_bd_addr), 17);   // strlen(bd_addr_to_str(...)) = 17
1075                 local_name[8+17] = '\0';
1076                 log_info("---> Name %s", local_name);
1077                 hci_send_cmd(&hci_write_local_name, local_name);
1078             }
1079             break;
1080         case HCI_INIT_WRITE_SCAN_ENABLE:
1081             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1082             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1083             break;
1084         // only sent if ENABLE_SCO_OVER_HCI is defined
1085         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1086             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1087             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1088             break;
1089         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1090             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1091             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1092             break;
1093 #ifdef ENABLE_BLE
1094         // LE INIT
1095         case HCI_INIT_LE_READ_BUFFER_SIZE:
1096             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1097             hci_send_cmd(&hci_le_read_buffer_size);
1098             break;
1099         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1100             // LE Supported Host = 1, Simultaneous Host = 0
1101             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1102             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1103             break;
1104         case HCI_INIT_READ_WHITE_LIST_SIZE:
1105             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1106             hci_send_cmd(&hci_le_read_white_list_size);
1107             break;
1108         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1109             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, public address, accept all advs
1110             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1111             hci_send_cmd(&hci_le_set_scan_parameters, 1, 0x1e0, 0x30, 0, 0);
1112             break;
1113 #endif
1114         default:
1115             return;
1116     }
1117 }
1118 
1119 static void hci_init_done(void){
1120     // done. tell the app
1121     log_info("hci_init_done -> HCI_STATE_WORKING");
1122     hci_stack->state = HCI_STATE_WORKING;
1123     hci_emit_state();
1124     hci_run();
1125 }
1126 
1127 static void hci_initializing_event_handler(uint8_t * packet, uint16_t size){
1128     uint8_t command_completed = 0;
1129 
1130     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1131         uint16_t opcode = little_endian_read_16(packet,3);
1132         if (opcode == hci_stack->last_cmd_opcode){
1133             command_completed = 1;
1134             log_info("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1135         } else {
1136             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1137         }
1138     }
1139 
1140     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1141         uint8_t  status = packet[2];
1142         uint16_t opcode = little_endian_read_16(packet,4);
1143         if (opcode == hci_stack->last_cmd_opcode){
1144             if (status){
1145                 command_completed = 1;
1146                 log_error("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1147             } else {
1148                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1149             }
1150         } else {
1151             log_info("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1152         }
1153     }
1154 
1155     // Vendor == CSR
1156     if (hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1157         // TODO: track actual command
1158         command_completed = 1;
1159     }
1160 
1161     // Vendor == Toshiba
1162     if (hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE && hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC){
1163         // TODO: track actual command
1164         command_completed = 1;
1165     }
1166 
1167     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1168     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1169     //
1170     // HCI Reset
1171     // Timeout 100 ms
1172     // HCI Reset
1173     // Command Complete Reset
1174     // HCI Read Local Version Information
1175     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1176     // hang...
1177     //
1178     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1179     if (!command_completed
1180             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1181             && hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION){
1182 
1183         uint16_t opcode = little_endian_read_16(packet,3);
1184         if (opcode == hci_reset.opcode){
1185             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1186             return;
1187         }
1188     }
1189 
1190     // CSR & H5
1191     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1192     if (!command_completed
1193             && hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE
1194             && hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS){
1195 
1196         uint16_t opcode = little_endian_read_16(packet,3);
1197         if (opcode == hci_reset.opcode){
1198             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1199             return;
1200         }
1201     }
1202 
1203     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1204     // fix: Correct substate and behave as command below
1205     if (command_completed){
1206         switch (hci_stack->substate){
1207             case HCI_INIT_SEND_RESET:
1208                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1209                 break;
1210             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1211                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1212                 break;
1213             default:
1214                 break;
1215         }
1216     }
1217 
1218 
1219     if (!command_completed) return;
1220 
1221     int need_baud_change = hci_stack->config
1222                         && hci_stack->chipset
1223                         && hci_stack->chipset->set_baudrate_command
1224                         && hci_stack->hci_transport->set_baudrate
1225                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1226 
1227     int need_addr_change = hci_stack->custom_bd_addr_set
1228                         && hci_stack->chipset
1229                         && hci_stack->chipset->set_bd_addr_command;
1230 
1231     switch(hci_stack->substate){
1232         case HCI_INIT_SEND_RESET:
1233             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1234             // fix: just correct substate and behave as command below
1235             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1236             btstack_run_loop_remove_timer(&hci_stack->timeout);
1237             break;
1238         case HCI_INIT_W4_SEND_RESET:
1239             btstack_run_loop_remove_timer(&hci_stack->timeout);
1240             break;
1241         case HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION:
1242             log_info("Received local version info, need baud change %u", need_baud_change);
1243             if (need_baud_change){
1244                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1245                 return;
1246             }
1247             // skip baud change
1248             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1249             return;
1250         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1251             // for STLC2500D, baud rate change already happened.
1252             // for others, baud rate gets changed now
1253             if ((hci_stack->manufacturer != COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1254                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1255                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1256                 hci_stack->hci_transport->set_baudrate(baud_rate);
1257             }
1258             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1259             return;
1260         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1261             btstack_run_loop_remove_timer(&hci_stack->timeout);
1262             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1263             return;
1264         case HCI_INIT_W4_CUSTOM_INIT:
1265             // repeat custom init
1266             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1267             return;
1268         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1269             if (need_baud_change && hci_stack->manufacturer == COMPANY_ID_BROADCOM_CORPORATION){
1270                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1271                 return;
1272             }
1273             if (need_addr_change){
1274                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1275                 return;
1276             }
1277             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1278             return;
1279         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1280             if (need_baud_change){
1281                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1282                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1283                 hci_stack->hci_transport->set_baudrate(baud_rate);
1284             }
1285             if (need_addr_change){
1286                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1287                 return;
1288             }
1289             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1290             return;
1291         case HCI_INIT_W4_SET_BD_ADDR:
1292             // for STLC2500D, bd addr change only gets active after sending reset command
1293             if (hci_stack->manufacturer == COMPANY_ID_ST_MICROELECTRONICS){
1294                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1295                 return;
1296             }
1297             // skipping st warm boot
1298             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1299             return;
1300         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1301             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1302             return;
1303         case HCI_INIT_W4_READ_BD_ADDR:
1304             // only read buffer size if supported
1305             if (hci_stack->local_supported_commands[0] & 0x01) {
1306                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1307                 return;
1308             }
1309             // skipping read buffer size
1310             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1311             return;
1312         case HCI_INIT_W4_SET_EVENT_MASK:
1313             // skip Classic init commands for LE only chipsets
1314             if (!hci_classic_supported()){
1315                 if (hci_le_supported()){
1316                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1317                     return;
1318                 } else {
1319                     log_error("Neither BR/EDR nor LE supported");
1320                     hci_init_done();
1321                     return;
1322                 }
1323             }
1324             if (!gap_ssp_supported()){
1325                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1326                 return;
1327             }
1328             break;
1329         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1330             break;
1331         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1332             // skip write le host if not supported (e.g. on LE only EM9301)
1333             if (hci_stack->local_supported_commands[0] & 0x02) break;
1334             hci_stack->substate = HCI_INIT_LE_SET_SCAN_PARAMETERS;
1335             return;
1336 
1337 #ifdef ENABLE_SCO_OVER_HCI
1338         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1339         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1340             break;
1341         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1342             if (!hci_le_supported()){
1343                 // SKIP LE init for Classic only configuration
1344                 hci_init_done();
1345                 return;
1346             }
1347             break;
1348 #else
1349         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1350             if (!hci_le_supported()){
1351                 // SKIP LE init for Classic only configuration
1352                 hci_init_done();
1353                 return;
1354             }
1355 #endif
1356             break;
1357         // Response to command before init done state -> init done
1358         case (HCI_INIT_DONE-1):
1359             hci_init_done();
1360             return;
1361 
1362         default:
1363             break;
1364     }
1365     hci_initializing_next_state();
1366 }
1367 
1368 static void event_handler(uint8_t *packet, int size){
1369 
1370     uint16_t event_length = packet[1];
1371 
1372     // assert packet is complete
1373     if (size != event_length + 2){
1374         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
1375         return;
1376     }
1377 
1378     bd_addr_t addr;
1379     bd_addr_type_t addr_type;
1380     uint8_t link_type;
1381     hci_con_handle_t handle;
1382     hci_connection_t * conn;
1383     int i;
1384 
1385     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1386 
1387     switch (hci_event_packet_get_type(packet)) {
1388 
1389         case HCI_EVENT_COMMAND_COMPLETE:
1390             // get num cmd packets
1391             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u", hci_stack->num_cmd_packets, packet[2]);
1392             hci_stack->num_cmd_packets = packet[2];
1393 
1394             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1395                 // from offset 5
1396                 // status
1397                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1398                 hci_stack->acl_data_packet_length = little_endian_read_16(packet, 6);
1399                 hci_stack->sco_data_packet_length = packet[8];
1400                 hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1401                 hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1402 
1403                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1404                     // determine usable ACL payload size
1405                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
1406                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1407                     }
1408                     log_info("hci_read_buffer_size: acl used size %u, count %u / sco size %u, count %u",
1409                              hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1410                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1411                 }
1412             }
1413 #ifdef ENABLE_BLE
1414             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1415                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1416                 hci_stack->le_acl_packets_total_num  = packet[8];
1417                     // determine usable ACL payload size
1418                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1419                         hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1420                     }
1421                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1422             }
1423             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1424                 hci_stack->le_whitelist_capacity = little_endian_read_16(packet, 6);
1425                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1426             }
1427 #endif
1428             // Dump local address
1429             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1430                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1431 				hci_stack->local_bd_addr);
1432                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1433                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1434                 if (hci_stack->link_key_db){
1435                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1436                 }
1437             }
1438             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1439                 hci_emit_discoverable_enabled(hci_stack->discoverable);
1440             }
1441             // Note: HCI init checks
1442             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
1443                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
1444 
1445                 // determine usable ACL packet types based on host buffer size and supported features
1446                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
1447                 log_info("packet types %04x", hci_stack->packet_types);
1448 
1449                 // Classic/LE
1450                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
1451             }
1452             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
1453                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
1454                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
1455                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
1456                 hci_stack->manufacturer   = little_endian_read_16(packet, 10);
1457                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
1458                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
1459                 // notify app
1460                 if (hci_stack->local_version_information_callback){
1461                     hci_stack->local_version_information_callback(packet);
1462                 }
1463             }
1464             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
1465                 hci_stack->local_supported_commands[0] =
1466                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0X80) >> 7 |  // Octet 14, bit 7
1467                     (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5;   // Octet 24, bit 6
1468             }
1469             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
1470                 if (packet[5] == 0){
1471                     hci_stack->synchronous_flow_control_enabled = 1;
1472                 }
1473             }
1474             break;
1475 
1476         case HCI_EVENT_COMMAND_STATUS:
1477             // get num cmd packets
1478             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u", hci_stack->num_cmd_packets, packet[3]);
1479             hci_stack->num_cmd_packets = packet[3];
1480             break;
1481 
1482         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
1483             int offset = 3;
1484             for (i=0; i<packet[2];i++){
1485                 handle = little_endian_read_16(packet, offset);
1486                 offset += 2;
1487                 uint16_t num_packets = little_endian_read_16(packet, offset);
1488                 offset += 2;
1489 
1490                 conn = hci_connection_for_handle(handle);
1491                 if (!conn){
1492                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
1493                     continue;
1494                 }
1495 
1496                 if (conn->address_type == BD_ADDR_TYPE_SCO){
1497                     if (conn->num_sco_packets_sent >= num_packets){
1498                         conn->num_sco_packets_sent -= num_packets;
1499                     } else {
1500                         log_error("hci_number_completed_packets, more sco slots freed then sent.");
1501                         conn->num_sco_packets_sent = 0;
1502                     }
1503                     hci_notify_if_sco_can_send_now();
1504                 } else {
1505                     if (conn->num_acl_packets_sent >= num_packets){
1506                         conn->num_acl_packets_sent -= num_packets;
1507                     } else {
1508                         log_error("hci_number_completed_packets, more acl slots freed then sent.");
1509                         conn->num_acl_packets_sent = 0;
1510                     }
1511                 }
1512                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_acl_packets_sent);
1513             }
1514             break;
1515         }
1516         case HCI_EVENT_CONNECTION_REQUEST:
1517             reverse_bd_addr(&packet[2], addr);
1518             // TODO: eval COD 8-10
1519             link_type = packet[11];
1520             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
1521             addr_type = link_type == 1 ? BD_ADDR_TYPE_CLASSIC : BD_ADDR_TYPE_SCO;
1522             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1523             if (!conn) {
1524                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1525             }
1526             if (!conn) {
1527                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
1528                 hci_stack->decline_reason = 0x0d;
1529                 bd_addr_copy(hci_stack->decline_addr, addr);
1530                 break;
1531             }
1532             conn->role  = HCI_ROLE_SLAVE;
1533             conn->state = RECEIVED_CONNECTION_REQUEST;
1534             // store info about eSCO
1535             if (link_type == 0x02){
1536                 conn->remote_supported_feature_eSCO = 1;
1537             }
1538             hci_run();
1539             break;
1540 
1541         case HCI_EVENT_CONNECTION_COMPLETE:
1542             // Connection management
1543             reverse_bd_addr(&packet[5], addr);
1544             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1545             addr_type = BD_ADDR_TYPE_CLASSIC;
1546             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1547             if (conn) {
1548                 if (!packet[2]){
1549                     conn->state = OPEN;
1550                     conn->con_handle = little_endian_read_16(packet, 3);
1551                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
1552 
1553                     // restart timer
1554                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1555                     btstack_run_loop_add_timer(&conn->timeout);
1556 
1557                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1558 
1559                     hci_emit_nr_connections_changed();
1560                 } else {
1561                     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1562                     uint8_t status = packet[2];
1563                     bd_addr_t bd_address;
1564                     memcpy(&bd_address, conn->address, 6);
1565 
1566                     // connection failed, remove entry
1567                     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1568                     btstack_memory_hci_connection_free( conn );
1569 
1570                     // notify client if dedicated bonding
1571                     if (notify_dedicated_bonding_failed){
1572                         log_info("hci notify_dedicated_bonding_failed");
1573                         hci_emit_dedicated_bonding_result(bd_address, status);
1574                     }
1575 
1576                     // if authentication error, also delete link key
1577                     if (packet[2] == 0x05) {
1578                         gap_drop_link_key_for_bd_addr(addr);
1579                     }
1580                 }
1581             }
1582             break;
1583 
1584         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
1585             reverse_bd_addr(&packet[5], addr);
1586             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
1587             if (packet[2]){
1588                 // connection failed
1589                 break;
1590             }
1591             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1592             if (!conn) {
1593                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
1594             }
1595             if (!conn) {
1596                 break;
1597             }
1598             conn->state = OPEN;
1599             conn->con_handle = little_endian_read_16(packet, 3);
1600             break;
1601 
1602         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
1603             handle = little_endian_read_16(packet, 3);
1604             conn = hci_connection_for_handle(handle);
1605             if (!conn) break;
1606             if (!packet[2]){
1607                 uint8_t * features = &packet[5];
1608                 if (features[6] & (1 << 3)){
1609                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
1610                 }
1611                 if (features[3] & (1<<7)){
1612                     conn->remote_supported_feature_eSCO = 1;
1613                 }
1614             }
1615             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1616             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
1617             if (conn->bonding_flags & BONDING_DEDICATED){
1618                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1619             }
1620             break;
1621 
1622         case HCI_EVENT_LINK_KEY_REQUEST:
1623             log_info("HCI_EVENT_LINK_KEY_REQUEST");
1624             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
1625             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
1626             if (hci_stack->bondable && !hci_stack->link_key_db) break;
1627             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
1628             hci_run();
1629             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
1630             return;
1631 
1632         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
1633             reverse_bd_addr(&packet[2], addr);
1634             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1635             if (!conn) break;
1636             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
1637             link_key_type_t link_key_type = (link_key_type_t)packet[24];
1638             // Change Connection Encryption keeps link key type
1639             if (link_key_type != CHANGED_COMBINATION_KEY){
1640                 conn->link_key_type = link_key_type;
1641             }
1642             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
1643             // still forward event to allow dismiss of pairing dialog
1644             break;
1645         }
1646 
1647         case HCI_EVENT_PIN_CODE_REQUEST:
1648             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
1649             // non-bondable mode: pin code negative reply will be sent
1650             if (!hci_stack->bondable){
1651                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
1652                 hci_run();
1653                 return;
1654             }
1655             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
1656             if (!hci_stack->link_key_db) break;
1657             hci_event_pin_code_request_get_bd_addr(packet, addr);
1658             hci_stack->link_key_db->delete_link_key(addr);
1659             break;
1660 
1661         case HCI_EVENT_IO_CAPABILITY_REQUEST:
1662             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
1663             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
1664             break;
1665 
1666         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
1667             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1668             if (!hci_stack->ssp_auto_accept) break;
1669             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
1670             break;
1671 
1672         case HCI_EVENT_USER_PASSKEY_REQUEST:
1673             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
1674             if (!hci_stack->ssp_auto_accept) break;
1675             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
1676             break;
1677 
1678         case HCI_EVENT_ENCRYPTION_CHANGE:
1679             handle = little_endian_read_16(packet, 3);
1680             conn = hci_connection_for_handle(handle);
1681             if (!conn) break;
1682             if (packet[2] == 0) {
1683                 if (packet[5]){
1684                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1685                 } else {
1686                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
1687                 }
1688             }
1689             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1690             break;
1691 
1692         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
1693             handle = little_endian_read_16(packet, 3);
1694             conn = hci_connection_for_handle(handle);
1695             if (!conn) break;
1696 
1697             // dedicated bonding: send result and disconnect
1698             if (conn->bonding_flags & BONDING_DEDICATED){
1699                 conn->bonding_flags &= ~BONDING_DEDICATED;
1700                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
1701                 conn->bonding_status = packet[2];
1702                 break;
1703             }
1704 
1705             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
1706                 // link key sufficient for requested security
1707                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
1708                 break;
1709             }
1710             // not enough
1711             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
1712             break;
1713 
1714         // HCI_EVENT_DISCONNECTION_COMPLETE
1715         // has been split, to first notify stack before shutting connection down
1716         // see end of function, too.
1717         case HCI_EVENT_DISCONNECTION_COMPLETE:
1718             if (packet[2]) break;   // status != 0
1719             handle = little_endian_read_16(packet, 3);
1720             conn = hci_connection_for_handle(handle);
1721             if (!conn) break;       // no conn struct anymore
1722             // re-enable advertisements for le connections if active
1723             if (hci_is_le_connection(conn) && hci_stack->le_advertisements_enabled){
1724                 hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1725             }
1726             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
1727             break;
1728 
1729         case HCI_EVENT_HARDWARE_ERROR:
1730             log_error("Hardware Error: 0x%02x", packet[2]);
1731             if (hci_stack->hardware_error_callback){
1732                 (*hci_stack->hardware_error_callback)(packet[2]);
1733             } else {
1734                 // if no special requests, just reboot stack
1735                 hci_power_control_off();
1736                 hci_power_control_on();
1737             }
1738             break;
1739 
1740         case HCI_EVENT_ROLE_CHANGE:
1741             if (packet[2]) break;   // status != 0
1742             handle = little_endian_read_16(packet, 3);
1743             conn = hci_connection_for_handle(handle);
1744             if (!conn) break;       // no conn
1745             conn->role = packet[9];
1746             break;
1747 
1748         case HCI_EVENT_TRANSPORT_PACKET_SENT:
1749             // release packet buffer only for asynchronous transport and if there are not further fragements
1750             if (hci_transport_synchronous()) {
1751                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
1752                 return; // instead of break: to avoid re-entering hci_run()
1753             }
1754             if (hci_stack->acl_fragmentation_total_size) break;
1755             hci_release_packet_buffer();
1756 
1757             // L2CAP receives this event via the hci_emit_event below
1758 
1759             // For SCO, we do the can_send_now_check here
1760             hci_notify_if_sco_can_send_now();
1761             break;
1762 
1763         case HCI_EVENT_SCO_CAN_SEND_NOW:
1764             // For SCO, we do the can_send_now_check here
1765             hci_notify_if_sco_can_send_now();
1766             return;
1767 
1768 #ifdef ENABLE_BLE
1769         case HCI_EVENT_LE_META:
1770             switch (packet[2]){
1771                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
1772                     // log_info("advertising report received");
1773                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
1774                     le_handle_advertisement_report(packet, size);
1775                     break;
1776                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
1777                     // Connection management
1778                     reverse_bd_addr(&packet[8], addr);
1779                     addr_type = (bd_addr_type_t)packet[7];
1780                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
1781                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
1782                     // if auto-connect, remove from whitelist in both roles
1783                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
1784                         hci_remove_from_whitelist(addr_type, addr);
1785                     }
1786                     // handle error: error is reported only to the initiator -> outgoing connection
1787                     if (packet[3]){
1788                         // outgoing connection establishment is done
1789                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1790                         // remove entry
1791                         if (conn){
1792                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1793                             btstack_memory_hci_connection_free( conn );
1794                         }
1795                         break;
1796                     }
1797                     // on success, both hosts receive connection complete event
1798                     if (packet[6] == HCI_ROLE_MASTER){
1799                         // if we're master, it was an outgoing connection and we're done with it
1800                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1801                     } else {
1802                         // if we're slave, it was an incoming connection, advertisements have stopped
1803                         hci_stack->le_advertisements_active = 0;
1804                     }
1805                     // LE connections are auto-accepted, so just create a connection if there isn't one already
1806                     if (!conn){
1807                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
1808                     }
1809                     // no memory, sorry.
1810                     if (!conn){
1811                         break;
1812                     }
1813 
1814                     conn->state = OPEN;
1815                     conn->role  = packet[6];
1816                     conn->con_handle = little_endian_read_16(packet, 4);
1817 
1818                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
1819 
1820                     // restart timer
1821                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
1822                     // btstack_run_loop_add_timer(&conn->timeout);
1823 
1824                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
1825 
1826                     hci_emit_nr_connections_changed();
1827                     break;
1828 
1829             // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
1830 
1831                 default:
1832                     break;
1833             }
1834             break;
1835 #endif
1836         default:
1837             break;
1838     }
1839 
1840     // handle BT initialization
1841     if (hci_stack->state == HCI_STATE_INITIALIZING){
1842         hci_initializing_event_handler(packet, size);
1843     }
1844 
1845     // help with BT sleep
1846     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
1847         && hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE
1848         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
1849         hci_initializing_next_state();
1850     }
1851 
1852     // notify upper stack
1853 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
1854 
1855     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
1856     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
1857         if (!packet[2]){
1858             handle = little_endian_read_16(packet, 3);
1859             hci_connection_t * aConn = hci_connection_for_handle(handle);
1860             if (aConn) {
1861                 uint8_t status = aConn->bonding_status;
1862                 uint16_t flags = aConn->bonding_flags;
1863                 bd_addr_t bd_address;
1864                 memcpy(&bd_address, aConn->address, 6);
1865                 hci_shutdown_connection(aConn);
1866                 // connection struct is gone, don't access anymore
1867                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
1868                     hci_emit_dedicated_bonding_result(bd_address, status);
1869                 }
1870             }
1871         }
1872     }
1873 
1874 	// execute main loop
1875 	hci_run();
1876 }
1877 
1878 static void sco_handler(uint8_t * packet, uint16_t size){
1879     if (!hci_stack->sco_packet_handler) return;
1880     hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
1881 }
1882 
1883 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
1884     hci_dump_packet(packet_type, 1, packet, size);
1885     switch (packet_type) {
1886         case HCI_EVENT_PACKET:
1887             event_handler(packet, size);
1888             break;
1889         case HCI_ACL_DATA_PACKET:
1890             acl_handler(packet, size);
1891             break;
1892         case HCI_SCO_DATA_PACKET:
1893             sco_handler(packet, size);
1894         default:
1895             break;
1896     }
1897 }
1898 
1899 /**
1900  * @brief Add event packet handler.
1901  */
1902 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
1903     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
1904 }
1905 
1906 
1907 /** Register HCI packet handlers */
1908 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
1909     hci_stack->acl_packet_handler = handler;
1910 }
1911 
1912 /**
1913  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
1914  */
1915 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
1916     hci_stack->sco_packet_handler = handler;
1917 }
1918 
1919 static void hci_state_reset(void){
1920     // no connections yet
1921     hci_stack->connections = NULL;
1922 
1923     // keep discoverable/connectable as this has been requested by the client(s)
1924     // hci_stack->discoverable = 0;
1925     // hci_stack->connectable = 0;
1926     // hci_stack->bondable = 1;
1927 
1928     // buffer is free
1929     hci_stack->hci_packet_buffer_reserved = 0;
1930 
1931     // no pending cmds
1932     hci_stack->decline_reason = 0;
1933     hci_stack->new_scan_enable_value = 0xff;
1934 
1935     // LE
1936     hci_stack->adv_addr_type = 0;
1937     memset(hci_stack->adv_address, 0, 6);
1938     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1939     hci_stack->le_scan_type = 0xff;
1940     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
1941     hci_stack->le_whitelist = 0;
1942     hci_stack->le_whitelist_capacity = 0;
1943     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
1944     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
1945     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
1946     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
1947     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
1948     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
1949 }
1950 
1951 /**
1952  * @brief Configure Bluetooth hardware control. Has to be called before power on.
1953  */
1954 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
1955     // store and open remote device db
1956     hci_stack->link_key_db = link_key_db;
1957     if (hci_stack->link_key_db) {
1958         hci_stack->link_key_db->open();
1959     }
1960 }
1961 
1962 void hci_init(const hci_transport_t *transport, const void *config){
1963 
1964 #ifdef HAVE_MALLOC
1965     if (!hci_stack) {
1966         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
1967     }
1968 #else
1969     hci_stack = &hci_stack_static;
1970 #endif
1971     memset(hci_stack, 0, sizeof(hci_stack_t));
1972 
1973     // reference to use transport layer implementation
1974     hci_stack->hci_transport = transport;
1975 
1976     // reference to used config
1977     hci_stack->config = config;
1978 
1979     // setup pointer for outgoing packet buffer
1980     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
1981 
1982     // max acl payload size defined in config.h
1983     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1984 
1985     // register packet handlers with transport
1986     transport->register_packet_handler(&packet_handler);
1987 
1988     hci_stack->state = HCI_STATE_OFF;
1989 
1990     // class of device
1991     hci_stack->class_of_device = 0x007a020c; // Smartphone
1992 
1993     // bondable by default
1994     hci_stack->bondable = 1;
1995 
1996     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
1997     hci_stack->ssp_enable = 1;
1998     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
1999     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2000     hci_stack->ssp_auto_accept = 1;
2001 
2002     // voice setting - signed 8 bit pcm data with CVSD over the air
2003     hci_stack->sco_voice_setting = 0x40;
2004 
2005     hci_state_reset();
2006 }
2007 
2008 /**
2009  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2010  */
2011 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2012     hci_stack->chipset = chipset_driver;
2013 
2014     // reset chipset driver - init is also called on power_up
2015     if (hci_stack->chipset && hci_stack->chipset->init){
2016         hci_stack->chipset->init(hci_stack->config);
2017     }
2018 }
2019 
2020 /**
2021  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2022  */
2023 void hci_set_control(const btstack_control_t *hardware_control){
2024     // references to used control implementation
2025     hci_stack->control = hardware_control;
2026     // init with transport config
2027     hardware_control->init(hci_stack->config);
2028 }
2029 
2030 void hci_close(void){
2031     // close remote device db
2032     if (hci_stack->link_key_db) {
2033         hci_stack->link_key_db->close();
2034     }
2035 
2036     btstack_linked_list_iterator_t lit;
2037     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2038     while (btstack_linked_list_iterator_has_next(&lit)){
2039         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2040         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2041         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2042         hci_shutdown_connection(connection);
2043     }
2044 
2045     hci_power_control(HCI_POWER_OFF);
2046 
2047 #ifdef HAVE_MALLOC
2048     free(hci_stack);
2049 #endif
2050     hci_stack = NULL;
2051 }
2052 
2053 void gap_set_class_of_device(uint32_t class_of_device){
2054     hci_stack->class_of_device = class_of_device;
2055 }
2056 
2057 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2058 void hci_set_bd_addr(bd_addr_t addr){
2059     memcpy(hci_stack->custom_bd_addr, addr, 6);
2060     hci_stack->custom_bd_addr_set = 1;
2061 }
2062 
2063 void hci_disable_l2cap_timeout_check(void){
2064     disable_l2cap_timeouts = 1;
2065 }
2066 // State-Module-Driver overview
2067 // state                    module  low-level
2068 // HCI_STATE_OFF             off      close
2069 // HCI_STATE_INITIALIZING,   on       open
2070 // HCI_STATE_WORKING,        on       open
2071 // HCI_STATE_HALTING,        on       open
2072 // HCI_STATE_SLEEPING,    off/sleep   close
2073 // HCI_STATE_FALLING_ASLEEP  on       open
2074 
2075 static int hci_power_control_on(void){
2076 
2077     // power on
2078     int err = 0;
2079     if (hci_stack->control && hci_stack->control->on){
2080         err = (*hci_stack->control->on)();
2081     }
2082     if (err){
2083         log_error( "POWER_ON failed");
2084         hci_emit_hci_open_failed();
2085         return err;
2086     }
2087 
2088     // int chipset driver
2089     if (hci_stack->chipset && hci_stack->chipset->init){
2090         hci_stack->chipset->init(hci_stack->config);
2091     }
2092 
2093     // init transport
2094     if (hci_stack->hci_transport->init){
2095         hci_stack->hci_transport->init(hci_stack->config);
2096     }
2097 
2098     // open transport
2099     err = hci_stack->hci_transport->open();
2100     if (err){
2101         log_error( "HCI_INIT failed, turning Bluetooth off again");
2102         if (hci_stack->control && hci_stack->control->off){
2103             (*hci_stack->control->off)();
2104         }
2105         hci_emit_hci_open_failed();
2106         return err;
2107     }
2108     return 0;
2109 }
2110 
2111 static void hci_power_control_off(void){
2112 
2113     log_info("hci_power_control_off");
2114 
2115     // close low-level device
2116     hci_stack->hci_transport->close();
2117 
2118     log_info("hci_power_control_off - hci_transport closed");
2119 
2120     // power off
2121     if (hci_stack->control && hci_stack->control->off){
2122         (*hci_stack->control->off)();
2123     }
2124 
2125     log_info("hci_power_control_off - control closed");
2126 
2127     hci_stack->state = HCI_STATE_OFF;
2128 }
2129 
2130 static void hci_power_control_sleep(void){
2131 
2132     log_info("hci_power_control_sleep");
2133 
2134 #if 0
2135     // don't close serial port during sleep
2136 
2137     // close low-level device
2138     hci_stack->hci_transport->close(hci_stack->config);
2139 #endif
2140 
2141     // sleep mode
2142     if (hci_stack->control && hci_stack->control->sleep){
2143         (*hci_stack->control->sleep)();
2144     }
2145 
2146     hci_stack->state = HCI_STATE_SLEEPING;
2147 }
2148 
2149 static int hci_power_control_wake(void){
2150 
2151     log_info("hci_power_control_wake");
2152 
2153     // wake on
2154     if (hci_stack->control && hci_stack->control->wake){
2155         (*hci_stack->control->wake)();
2156     }
2157 
2158 #if 0
2159     // open low-level device
2160     int err = hci_stack->hci_transport->open(hci_stack->config);
2161     if (err){
2162         log_error( "HCI_INIT failed, turning Bluetooth off again");
2163         if (hci_stack->control && hci_stack->control->off){
2164             (*hci_stack->control->off)();
2165         }
2166         hci_emit_hci_open_failed();
2167         return err;
2168     }
2169 #endif
2170 
2171     return 0;
2172 }
2173 
2174 static void hci_power_transition_to_initializing(void){
2175     // set up state machine
2176     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2177     hci_stack->hci_packet_buffer_reserved = 0;
2178     hci_stack->state = HCI_STATE_INITIALIZING;
2179     hci_stack->substate = HCI_INIT_SEND_RESET;
2180 }
2181 
2182 int hci_power_control(HCI_POWER_MODE power_mode){
2183 
2184     log_info("hci_power_control: %u, current mode %u", power_mode, hci_stack->state);
2185 
2186     int err = 0;
2187     switch (hci_stack->state){
2188 
2189         case HCI_STATE_OFF:
2190             switch (power_mode){
2191                 case HCI_POWER_ON:
2192                     err = hci_power_control_on();
2193                     if (err) {
2194                         log_error("hci_power_control_on() error %u", err);
2195                         return err;
2196                     }
2197                     hci_power_transition_to_initializing();
2198                     break;
2199                 case HCI_POWER_OFF:
2200                     // do nothing
2201                     break;
2202                 case HCI_POWER_SLEEP:
2203                     // do nothing (with SLEEP == OFF)
2204                     break;
2205             }
2206             break;
2207 
2208         case HCI_STATE_INITIALIZING:
2209             switch (power_mode){
2210                 case HCI_POWER_ON:
2211                     // do nothing
2212                     break;
2213                 case HCI_POWER_OFF:
2214                     // no connections yet, just turn it off
2215                     hci_power_control_off();
2216                     break;
2217                 case HCI_POWER_SLEEP:
2218                     // no connections yet, just turn it off
2219                     hci_power_control_sleep();
2220                     break;
2221             }
2222             break;
2223 
2224         case HCI_STATE_WORKING:
2225             switch (power_mode){
2226                 case HCI_POWER_ON:
2227                     // do nothing
2228                     break;
2229                 case HCI_POWER_OFF:
2230                     // see hci_run
2231                     hci_stack->state = HCI_STATE_HALTING;
2232                     break;
2233                 case HCI_POWER_SLEEP:
2234                     // see hci_run
2235                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2236                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2237                     break;
2238             }
2239             break;
2240 
2241         case HCI_STATE_HALTING:
2242             switch (power_mode){
2243                 case HCI_POWER_ON:
2244                     hci_power_transition_to_initializing();
2245                     break;
2246                 case HCI_POWER_OFF:
2247                     // do nothing
2248                     break;
2249                 case HCI_POWER_SLEEP:
2250                     // see hci_run
2251                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2252                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2253                     break;
2254             }
2255             break;
2256 
2257         case HCI_STATE_FALLING_ASLEEP:
2258             switch (power_mode){
2259                 case HCI_POWER_ON:
2260 
2261 #ifdef HAVE_PLATFORM_IPHONE_OS
2262                     // nothing to do, if H4 supports power management
2263                     if (btstack_control_iphone_power_management_enabled()){
2264                         hci_stack->state = HCI_STATE_INITIALIZING;
2265                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2266                         break;
2267                     }
2268 #endif
2269                     hci_power_transition_to_initializing();
2270                     break;
2271                 case HCI_POWER_OFF:
2272                     // see hci_run
2273                     hci_stack->state = HCI_STATE_HALTING;
2274                     break;
2275                 case HCI_POWER_SLEEP:
2276                     // do nothing
2277                     break;
2278             }
2279             break;
2280 
2281         case HCI_STATE_SLEEPING:
2282             switch (power_mode){
2283                 case HCI_POWER_ON:
2284 
2285 #ifdef HAVE_PLATFORM_IPHONE_OS
2286                     // nothing to do, if H4 supports power management
2287                     if (btstack_control_iphone_power_management_enabled()){
2288                         hci_stack->state = HCI_STATE_INITIALIZING;
2289                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2290                         hci_update_scan_enable();
2291                         break;
2292                     }
2293 #endif
2294                     err = hci_power_control_wake();
2295                     if (err) return err;
2296                     hci_power_transition_to_initializing();
2297                     break;
2298                 case HCI_POWER_OFF:
2299                     hci_stack->state = HCI_STATE_HALTING;
2300                     break;
2301                 case HCI_POWER_SLEEP:
2302                     // do nothing
2303                     break;
2304             }
2305             break;
2306     }
2307 
2308     // create internal event
2309 	hci_emit_state();
2310 
2311 	// trigger next/first action
2312 	hci_run();
2313 
2314     return 0;
2315 }
2316 
2317 static void hci_update_scan_enable(void){
2318     // 2 = page scan, 1 = inq scan
2319     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2320     hci_run();
2321 }
2322 
2323 void gap_discoverable_control(uint8_t enable){
2324     if (enable) enable = 1; // normalize argument
2325 
2326     if (hci_stack->discoverable == enable){
2327         hci_emit_discoverable_enabled(hci_stack->discoverable);
2328         return;
2329     }
2330 
2331     hci_stack->discoverable = enable;
2332     hci_update_scan_enable();
2333 }
2334 
2335 void gap_connectable_control(uint8_t enable){
2336     if (enable) enable = 1; // normalize argument
2337 
2338     // don't emit event
2339     if (hci_stack->connectable == enable) return;
2340 
2341     hci_stack->connectable = enable;
2342     hci_update_scan_enable();
2343 }
2344 
2345 void gap_local_bd_addr(bd_addr_t address_buffer){
2346     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2347 }
2348 
2349 static void hci_run(void){
2350 
2351     // log_info("hci_run: entered");
2352     btstack_linked_item_t * it;
2353 
2354     // send continuation fragments first, as they block the prepared packet buffer
2355     if (hci_stack->acl_fragmentation_total_size > 0) {
2356         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2357         if (hci_can_send_prepared_acl_packet_now(con_handle)){
2358             hci_connection_t *connection = hci_connection_for_handle(con_handle);
2359             if (connection) {
2360                 hci_send_acl_packet_fragments(connection);
2361                 return;
2362             }
2363             // connection gone -> discard further fragments
2364             hci_stack->acl_fragmentation_total_size = 0;
2365             hci_stack->acl_fragmentation_pos = 0;
2366         }
2367     }
2368 
2369     if (!hci_can_send_command_packet_now()) return;
2370 
2371     // global/non-connection oriented commands
2372 
2373     // decline incoming connections
2374     if (hci_stack->decline_reason){
2375         uint8_t reason = hci_stack->decline_reason;
2376         hci_stack->decline_reason = 0;
2377         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2378         return;
2379     }
2380 
2381     // send scan enable
2382     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2383         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2384         hci_stack->new_scan_enable_value = 0xff;
2385         return;
2386     }
2387 
2388 #ifdef ENABLE_BLE
2389     if (hci_stack->state == HCI_STATE_WORKING){
2390         // handle le scan
2391         switch(hci_stack->le_scanning_state){
2392             case LE_START_SCAN:
2393                 hci_stack->le_scanning_state = LE_SCANNING;
2394                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2395                 return;
2396 
2397             case LE_STOP_SCAN:
2398                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2399                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2400                 return;
2401             default:
2402                 break;
2403         }
2404         if (hci_stack->le_scan_type != 0xff){
2405             // defaults: active scanning, accept all advertisement packets
2406             int scan_type = hci_stack->le_scan_type;
2407             hci_stack->le_scan_type = 0xff;
2408             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);
2409             return;
2410         }
2411         // le advertisement control
2412         if (hci_stack->le_advertisements_todo){
2413             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2414         }
2415         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2416             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2417             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2418             return;
2419         }
2420         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2421             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2422             hci_send_cmd(&hci_le_set_advertising_parameters,
2423                  hci_stack->le_advertisements_interval_min,
2424                  hci_stack->le_advertisements_interval_max,
2425                  hci_stack->le_advertisements_type,
2426                  hci_stack->le_advertisements_own_address_type,
2427                  hci_stack->le_advertisements_direct_address_type,
2428                  hci_stack->le_advertisements_direct_address,
2429                  hci_stack->le_advertisements_channel_map,
2430                  hci_stack->le_advertisements_filter_policy);
2431             return;
2432         }
2433         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2434             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2435             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2436                 hci_stack->le_advertisements_data);
2437             return;
2438         }
2439         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2440             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2441             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2442                 hci_stack->le_scan_response_data);
2443             return;
2444         }
2445         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2446             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2447             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2448             return;
2449         }
2450 
2451         //
2452         // LE Whitelist Management
2453         //
2454 
2455         // check if whitelist needs modification
2456         btstack_linked_list_iterator_t lit;
2457         int modification_pending = 0;
2458         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2459         while (btstack_linked_list_iterator_has_next(&lit)){
2460             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2461             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2462                 modification_pending = 1;
2463                 break;
2464             }
2465         }
2466 
2467         if (modification_pending){
2468             // stop connnecting if modification pending
2469             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2470                 hci_send_cmd(&hci_le_create_connection_cancel);
2471                 return;
2472             }
2473 
2474             // add/remove entries
2475             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2476             while (btstack_linked_list_iterator_has_next(&lit)){
2477                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2478                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2479                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2480                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2481                     return;
2482 
2483                 }
2484                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2485                     bd_addr_t address;
2486                     bd_addr_type_t address_type = entry->address_type;
2487                     memcpy(address, entry->address, 6);
2488                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2489                     btstack_memory_whitelist_entry_free(entry);
2490                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2491                     return;
2492                 }
2493             }
2494         }
2495 
2496         // start connecting
2497         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2498             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2499             bd_addr_t null_addr;
2500             memset(null_addr, 0, 6);
2501             hci_send_cmd(&hci_le_create_connection,
2502                  0x0060,    // scan interval: 60 ms
2503                  0x0030,    // scan interval: 30 ms
2504                  1,         // use whitelist
2505                  0,         // peer address type
2506                  null_addr,      // peer bd addr
2507                  hci_stack->adv_addr_type, // our addr type:
2508                  0x0008,    // conn interval min
2509                  0x0018,    // conn interval max
2510                  0,         // conn latency
2511                  0x0048,    // supervision timeout
2512                  0x0001,    // min ce length
2513                  0x0001     // max ce length
2514                  );
2515             return;
2516         }
2517     }
2518 #endif
2519 
2520     // send pending HCI commands
2521     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2522         hci_connection_t * connection = (hci_connection_t *) it;
2523 
2524         switch(connection->state){
2525             case SEND_CREATE_CONNECTION:
2526                 switch(connection->address_type){
2527                     case BD_ADDR_TYPE_CLASSIC:
2528                         log_info("sending hci_create_connection");
2529                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2530                         break;
2531                     default:
2532 #ifdef ENABLE_BLE
2533                         log_info("sending hci_le_create_connection");
2534                         hci_send_cmd(&hci_le_create_connection,
2535                                      0x0060,    // scan interval: 60 ms
2536                                      0x0030,    // scan interval: 30 ms
2537                                      0,         // don't use whitelist
2538                                      connection->address_type, // peer address type
2539                                      connection->address,      // peer bd addr
2540                                      hci_stack->adv_addr_type, // our addr type:
2541                                      0x0008,    // conn interval min
2542                                      0x0018,    // conn interval max
2543                                      0,         // conn latency
2544                                      0x0048,    // supervision timeout
2545                                      0x0001,    // min ce length
2546                                      0x0001     // max ce length
2547                                      );
2548 
2549                         connection->state = SENT_CREATE_CONNECTION;
2550 #endif
2551                         break;
2552                 }
2553                 return;
2554 
2555             case RECEIVED_CONNECTION_REQUEST:
2556                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2557                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2558                 connection->role  = HCI_ROLE_SLAVE;
2559                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2560                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2561                 } else {
2562                     // remote supported feature eSCO is set if link type is eSCO
2563                     uint16_t max_latency;
2564                     uint8_t  retransmission_effort;
2565                     uint16_t packet_types;
2566                     // remote supported feature eSCO is set if link type is eSCO
2567                     if (connection->remote_supported_feature_eSCO){
2568                         // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
2569                         max_latency = 0x000c;
2570                         retransmission_effort = 0x02;
2571                         packet_types = 0x388;
2572                     } else {
2573                         // SCO: max latency, retransmission interval: N/A. any packet type
2574                         max_latency = 0xffff;
2575                         retransmission_effort = 0xff;
2576                         packet_types = 0x003f;
2577                     }
2578                     hci_send_cmd(&hci_accept_synchronous_connection, connection->address, 8000, 8000, max_latency, hci_stack->sco_voice_setting, retransmission_effort, packet_types);
2579                 }
2580                 return;
2581 
2582 #ifdef ENABLE_BLE
2583             case SEND_CANCEL_CONNECTION:
2584                 connection->state = SENT_CANCEL_CONNECTION;
2585                 hci_send_cmd(&hci_le_create_connection_cancel);
2586                 return;
2587 #endif
2588             case SEND_DISCONNECT:
2589                 connection->state = SENT_DISCONNECT;
2590                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2591                 return;
2592 
2593             default:
2594                 break;
2595         }
2596 
2597         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2598             log_info("responding to link key request");
2599             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2600             link_key_t link_key;
2601             link_key_type_t link_key_type;
2602             if ( hci_stack->link_key_db
2603               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2604               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2605                connection->link_key_type = link_key_type;
2606                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2607             } else {
2608                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2609             }
2610             return;
2611         }
2612 
2613         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2614             log_info("denying to pin request");
2615             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2616             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2617             return;
2618         }
2619 
2620         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2621             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2622             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2623             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2624                 // tweak authentication requirements
2625                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2626                 if (connection->bonding_flags & BONDING_DEDICATED){
2627                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2628                 }
2629                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2630                     authreq |= 1;
2631                 }
2632                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2633             } else {
2634                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2635             }
2636             return;
2637         }
2638 
2639         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2640             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2641             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2642             return;
2643         }
2644 
2645         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2646             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2647             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2648             return;
2649         }
2650 
2651         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2652             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2653             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2654             return;
2655         }
2656 
2657         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2658             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2659             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2660             return;
2661         }
2662         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2663             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2664             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2665             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2666             return;
2667         }
2668         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2669             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2670             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2671             return;
2672         }
2673         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2674             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2675             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2676             return;
2677         }
2678 
2679 #ifdef ENABLE_BLE
2680         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2681             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2682 
2683             uint16_t connection_interval_min = connection->le_conn_interval_min;
2684             connection->le_conn_interval_min = 0;
2685             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2686                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2687                 0x0000, 0xffff);
2688         }
2689 #endif
2690     }
2691 
2692     hci_connection_t * connection;
2693     switch (hci_stack->state){
2694         case HCI_STATE_INITIALIZING:
2695             hci_initializing_run();
2696             break;
2697 
2698         case HCI_STATE_HALTING:
2699 
2700             log_info("HCI_STATE_HALTING");
2701 
2702             // free whitelist entries
2703 #ifdef ENABLE_BLE
2704             {
2705                 btstack_linked_list_iterator_t lit;
2706                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2707                 while (btstack_linked_list_iterator_has_next(&lit)){
2708                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2709                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2710                     btstack_memory_whitelist_entry_free(entry);
2711                 }
2712             }
2713 #endif
2714             // close all open connections
2715             connection =  (hci_connection_t *) hci_stack->connections;
2716             if (connection){
2717                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2718                 if (!hci_can_send_command_packet_now()) return;
2719 
2720                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2721 
2722                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2723                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2724 
2725                 // ... which would be ignored anyway as we shutdown (free) the connection now
2726                 hci_shutdown_connection(connection);
2727 
2728                 // finally, send the disconnect command
2729                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2730                 return;
2731             }
2732             log_info("HCI_STATE_HALTING, calling off");
2733 
2734             // switch mode
2735             hci_power_control_off();
2736 
2737             log_info("HCI_STATE_HALTING, emitting state");
2738             hci_emit_state();
2739             log_info("HCI_STATE_HALTING, done");
2740             break;
2741 
2742         case HCI_STATE_FALLING_ASLEEP:
2743             switch(hci_stack->substate) {
2744                 case HCI_FALLING_ASLEEP_DISCONNECT:
2745                     log_info("HCI_STATE_FALLING_ASLEEP");
2746                     // close all open connections
2747                     connection =  (hci_connection_t *) hci_stack->connections;
2748 
2749 #ifdef HAVE_PLATFORM_IPHONE_OS
2750                     // don't close connections, if H4 supports power management
2751                     if (btstack_control_iphone_power_management_enabled()){
2752                         connection = NULL;
2753                     }
2754 #endif
2755                     if (connection){
2756 
2757                         // send disconnect
2758                         if (!hci_can_send_command_packet_now()) return;
2759 
2760                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2761                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2762 
2763                         // send disconnected event right away - causes higher layer connections to get closed, too.
2764                         hci_shutdown_connection(connection);
2765                         return;
2766                     }
2767 
2768                     if (hci_classic_supported()){
2769                         // disable page and inquiry scan
2770                         if (!hci_can_send_command_packet_now()) return;
2771 
2772                         log_info("HCI_STATE_HALTING, disabling inq scans");
2773                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2774 
2775                         // continue in next sub state
2776                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2777                         break;
2778                     }
2779                     // fall through for ble-only chips
2780 
2781                 case HCI_FALLING_ASLEEP_COMPLETE:
2782                     log_info("HCI_STATE_HALTING, calling sleep");
2783 #ifdef HAVE_PLATFORM_IPHONE_OS
2784                     // don't actually go to sleep, if H4 supports power management
2785                     if (btstack_control_iphone_power_management_enabled()){
2786                         // SLEEP MODE reached
2787                         hci_stack->state = HCI_STATE_SLEEPING;
2788                         hci_emit_state();
2789                         break;
2790                     }
2791 #endif
2792                     // switch mode
2793                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2794                     hci_emit_state();
2795                     break;
2796 
2797                 default:
2798                     break;
2799             }
2800             break;
2801 
2802         default:
2803             break;
2804     }
2805 }
2806 
2807 int hci_send_cmd_packet(uint8_t *packet, int size){
2808     bd_addr_t addr;
2809     hci_connection_t * conn;
2810     // house-keeping
2811 
2812     // create_connection?
2813     if (IS_COMMAND(packet, hci_create_connection)){
2814         reverse_bd_addr(&packet[3], addr);
2815         log_info("Create_connection to %s", bd_addr_to_str(addr));
2816 
2817         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2818         if (!conn){
2819             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2820             if (!conn){
2821                 // notify client that alloc failed
2822                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
2823                 return 0; // don't sent packet to controller
2824             }
2825             conn->state = SEND_CREATE_CONNECTION;
2826         }
2827         log_info("conn state %u", conn->state);
2828         switch (conn->state){
2829             // if connection active exists
2830             case OPEN:
2831                 // and OPEN, emit connection complete command, don't send to controller
2832                 hci_emit_connection_complete(addr, conn->con_handle, 0);
2833                 return 0;
2834             case SEND_CREATE_CONNECTION:
2835                 // connection created by hci, e.g. dedicated bonding
2836                 break;
2837             default:
2838                 // otherwise, just ignore as it is already in the open process
2839                 return 0;
2840         }
2841         conn->state = SENT_CREATE_CONNECTION;
2842     }
2843     if (IS_COMMAND(packet, hci_link_key_request_reply)){
2844         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
2845     }
2846     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
2847         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
2848     }
2849 
2850     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
2851         if (hci_stack->link_key_db){
2852             reverse_bd_addr(&packet[3], addr);
2853             hci_stack->link_key_db->delete_link_key(addr);
2854         }
2855     }
2856 
2857     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
2858     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
2859         reverse_bd_addr(&packet[3], addr);
2860         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2861         if (conn){
2862             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
2863         }
2864     }
2865 
2866     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
2867     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
2868     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
2869     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
2870         reverse_bd_addr(&packet[3], addr);
2871         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2872         if (conn){
2873             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
2874         }
2875     }
2876 
2877     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2878         hci_stack->loopback_mode = packet[3];
2879     }
2880 
2881 #ifdef ENABLE_BLE
2882     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
2883         hci_stack->adv_addr_type = packet[8];
2884     }
2885     if (IS_COMMAND(packet, hci_le_set_random_address)){
2886         reverse_bd_addr(&packet[3], hci_stack->adv_address);
2887     }
2888     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
2889         hci_stack->le_advertisements_active = packet[3];
2890     }
2891     if (IS_COMMAND(packet, hci_le_create_connection)){
2892         // white list used?
2893         uint8_t initiator_filter_policy = packet[7];
2894         switch (initiator_filter_policy){
2895             case 0:
2896                 // whitelist not used
2897                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
2898                 break;
2899             case 1:
2900                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
2901                 break;
2902             default:
2903                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
2904                 break;
2905         }
2906     }
2907     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
2908         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2909     }
2910 #endif
2911 
2912     hci_stack->num_cmd_packets--;
2913 
2914     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2915     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2916 
2917     // release packet buffer for synchronous transport implementations
2918     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
2919         hci_stack->hci_packet_buffer_reserved = 0;
2920     }
2921 
2922     return err;
2923 }
2924 
2925 // disconnect because of security block
2926 void hci_disconnect_security_block(hci_con_handle_t con_handle){
2927     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2928     if (!connection) return;
2929     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2930 }
2931 
2932 
2933 // Configure Secure Simple Pairing
2934 
2935 // enable will enable SSP during init
2936 void gap_ssp_set_enable(int enable){
2937     hci_stack->ssp_enable = enable;
2938 }
2939 
2940 static int hci_local_ssp_activated(void){
2941     return gap_ssp_supported() && hci_stack->ssp_enable;
2942 }
2943 
2944 // if set, BTstack will respond to io capability request using authentication requirement
2945 void gap_ssp_set_io_capability(int io_capability){
2946     hci_stack->ssp_io_capability = io_capability;
2947 }
2948 void gap_ssp_set_authentication_requirement(int authentication_requirement){
2949     hci_stack->ssp_authentication_requirement = authentication_requirement;
2950 }
2951 
2952 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
2953 void gap_ssp_set_auto_accept(int auto_accept){
2954     hci_stack->ssp_auto_accept = auto_accept;
2955 }
2956 
2957 /**
2958  * pre: numcmds >= 0 - it's allowed to send a command to the controller
2959  */
2960 int hci_send_cmd(const hci_cmd_t *cmd, ...){
2961 
2962     if (!hci_can_send_command_packet_now()){
2963         log_error("hci_send_cmd called but cannot send packet now");
2964         return 0;
2965     }
2966 
2967     // for HCI INITIALIZATION
2968     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
2969     hci_stack->last_cmd_opcode = cmd->opcode;
2970 
2971     hci_reserve_packet_buffer();
2972     uint8_t * packet = hci_stack->hci_packet_buffer;
2973 
2974     va_list argptr;
2975     va_start(argptr, cmd);
2976     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
2977     va_end(argptr);
2978 
2979     return hci_send_cmd_packet(packet, size);
2980 }
2981 
2982 // Create various non-HCI events.
2983 // TODO: generalize, use table similar to hci_create_command
2984 
2985 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
2986     // dump packet
2987     if (dump) {
2988         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
2989     }
2990 
2991     // dispatch to all event handlers
2992     btstack_linked_list_iterator_t it;
2993     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
2994     while (btstack_linked_list_iterator_has_next(&it)){
2995         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
2996         entry->callback(HCI_EVENT_PACKET, 0, event, size);
2997     }
2998 }
2999 
3000 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
3001     if (!hci_stack->acl_packet_handler) return;
3002     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3003 }
3004 
3005 static void hci_notify_if_sco_can_send_now(void){
3006     // notify SCO sender if waiting
3007     if (!hci_stack->sco_waiting_for_can_send_now) return;
3008     if (hci_can_send_sco_packet_now()){
3009         hci_stack->sco_waiting_for_can_send_now = 0;
3010         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3011         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3012         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3013     }
3014 }
3015 
3016 void hci_emit_state(void){
3017     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3018     uint8_t event[3];
3019     event[0] = BTSTACK_EVENT_STATE;
3020     event[1] = sizeof(event) - 2;
3021     event[2] = hci_stack->state;
3022     hci_emit_event(event, sizeof(event), 1);
3023 }
3024 
3025 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3026     uint8_t event[13];
3027     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3028     event[1] = sizeof(event) - 2;
3029     event[2] = status;
3030     little_endian_store_16(event, 3, con_handle);
3031     reverse_bd_addr(address, &event[5]);
3032     event[11] = 1; // ACL connection
3033     event[12] = 0; // encryption disabled
3034     hci_emit_event(event, sizeof(event), 1);
3035 }
3036 
3037 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3038     uint8_t event[21];
3039     event[0] = HCI_EVENT_LE_META;
3040     event[1] = sizeof(event) - 2;
3041     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3042     event[3] = status;
3043     little_endian_store_16(event, 4, con_handle);
3044     event[6] = 0; // TODO: role
3045     event[7] = address_type;
3046     reverse_bd_addr(address, &event[8]);
3047     little_endian_store_16(event, 14, 0); // interval
3048     little_endian_store_16(event, 16, 0); // latency
3049     little_endian_store_16(event, 18, 0); // supervision timeout
3050     event[20] = 0; // master clock accuracy
3051     hci_emit_event(event, sizeof(event), 1);
3052 }
3053 
3054 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3055     uint8_t event[6];
3056     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3057     event[1] = sizeof(event) - 2;
3058     event[2] = 0; // status = OK
3059     little_endian_store_16(event, 3, con_handle);
3060     event[5] = reason;
3061     hci_emit_event(event, sizeof(event), 1);
3062 }
3063 
3064 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3065     if (disable_l2cap_timeouts) return;
3066     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3067     uint8_t event[4];
3068     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3069     event[1] = sizeof(event) - 2;
3070     little_endian_store_16(event, 2, conn->con_handle);
3071     hci_emit_event(event, sizeof(event), 1);
3072 }
3073 
3074 static void hci_emit_nr_connections_changed(void){
3075     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3076     uint8_t event[3];
3077     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3078     event[1] = sizeof(event) - 2;
3079     event[2] = nr_hci_connections();
3080     hci_emit_event(event, sizeof(event), 1);
3081 }
3082 
3083 static void hci_emit_hci_open_failed(void){
3084     log_info("BTSTACK_EVENT_POWERON_FAILED");
3085     uint8_t event[2];
3086     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3087     event[1] = sizeof(event) - 2;
3088     hci_emit_event(event, sizeof(event), 1);
3089 }
3090 
3091 static void hci_emit_discoverable_enabled(uint8_t enabled){
3092     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3093     uint8_t event[3];
3094     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3095     event[1] = sizeof(event) - 2;
3096     event[2] = enabled;
3097     hci_emit_event(event, sizeof(event), 1);
3098 }
3099 
3100 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3101     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3102     uint8_t event[5];
3103     int pos = 0;
3104     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3105     event[pos++] = sizeof(event) - 2;
3106     little_endian_store_16(event, 2, con_handle);
3107     pos += 2;
3108     event[pos++] = level;
3109     hci_emit_event(event, sizeof(event), 1);
3110 }
3111 
3112 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3113     log_info("hci_emit_dedicated_bonding_result %u ", status);
3114     uint8_t event[9];
3115     int pos = 0;
3116     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3117     event[pos++] = sizeof(event) - 2;
3118     event[pos++] = status;
3119     reverse_bd_addr(address, &event[pos]);
3120     hci_emit_event(event, sizeof(event), 1);
3121 }
3122 
3123 // query if remote side supports eSCO
3124 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3125     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3126     if (!connection) return 0;
3127     return connection->remote_supported_feature_eSCO;
3128 }
3129 
3130 // query if remote side supports SSP
3131 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3132     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3133     if (!connection) return 0;
3134     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3135 }
3136 
3137 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3138     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3139 }
3140 
3141 // GAP API
3142 /**
3143  * @bbrief enable/disable bonding. default is enabled
3144  * @praram enabled
3145  */
3146 void gap_set_bondable_mode(int enable){
3147     hci_stack->bondable = enable ? 1 : 0;
3148 }
3149 /**
3150  * @brief Get bondable mode.
3151  * @return 1 if bondable
3152  */
3153 int gap_get_bondable_mode(void){
3154     return hci_stack->bondable;
3155 }
3156 
3157 /**
3158  * @brief map link keys to security levels
3159  */
3160 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3161     switch (link_key_type){
3162         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3163             return LEVEL_4;
3164         case COMBINATION_KEY:
3165         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3166             return LEVEL_3;
3167         default:
3168             return LEVEL_2;
3169     }
3170 }
3171 
3172 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3173     if (!connection) return LEVEL_0;
3174     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3175     return gap_security_level_for_link_key_type(connection->link_key_type);
3176 }
3177 
3178 
3179 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3180     log_info("gap_mitm_protection_required_for_security_level %u", level);
3181     return level > LEVEL_2;
3182 }
3183 
3184 /**
3185  * @brief get current security level
3186  */
3187 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3188     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3189     if (!connection) return LEVEL_0;
3190     return gap_security_level_for_connection(connection);
3191 }
3192 
3193 /**
3194  * @brief request connection to device to
3195  * @result GAP_AUTHENTICATION_RESULT
3196  */
3197 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3198     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3199     if (!connection){
3200         hci_emit_security_level(con_handle, LEVEL_0);
3201         return;
3202     }
3203     gap_security_level_t current_level = gap_security_level(con_handle);
3204     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3205     if (current_level >= requested_level){
3206         hci_emit_security_level(con_handle, current_level);
3207         return;
3208     }
3209 
3210     connection->requested_security_level = requested_level;
3211 
3212 #if 0
3213     // sending encryption request without a link key results in an error.
3214     // TODO: figure out how to use it properly
3215 
3216     // would enabling ecnryption suffice (>= LEVEL_2)?
3217     if (hci_stack->link_key_db){
3218         link_key_type_t link_key_type;
3219         link_key_t      link_key;
3220         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3221             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3222                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3223                 return;
3224             }
3225         }
3226     }
3227 #endif
3228 
3229     // try to authenticate connection
3230     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3231     hci_run();
3232 }
3233 
3234 /**
3235  * @brief start dedicated bonding with device. disconnect after bonding
3236  * @param device
3237  * @param request MITM protection
3238  * @result GAP_DEDICATED_BONDING_COMPLETE
3239  */
3240 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3241 
3242     // create connection state machine
3243     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3244 
3245     if (!connection){
3246         return BTSTACK_MEMORY_ALLOC_FAILED;
3247     }
3248 
3249     // delete linkn key
3250     gap_drop_link_key_for_bd_addr(device);
3251 
3252     // configure LEVEL_2/3, dedicated bonding
3253     connection->state = SEND_CREATE_CONNECTION;
3254     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3255     log_info("gap_dedicated_bonding, mitm %u -> level %u", mitm_protection_required, connection->requested_security_level);
3256     connection->bonding_flags = BONDING_DEDICATED;
3257 
3258     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3259 
3260     // handle: connnection failure (connection complete != ok)
3261     // handle: authentication failure
3262     // handle: disconnect on done
3263 
3264     hci_run();
3265 
3266     return 0;
3267 }
3268 
3269 void gap_set_local_name(const char * local_name){
3270     hci_stack->local_name = local_name;
3271 }
3272 
3273 void gap_start_scan(void){
3274     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3275     hci_stack->le_scanning_state = LE_START_SCAN;
3276     hci_run();
3277 }
3278 
3279 void gap_stop_scan(void){
3280     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3281     hci_stack->le_scanning_state = LE_STOP_SCAN;
3282     hci_run();
3283 }
3284 
3285 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3286     hci_stack->le_scan_type     = scan_type;
3287     hci_stack->le_scan_interval = scan_interval;
3288     hci_stack->le_scan_window   = scan_window;
3289     hci_run();
3290 }
3291 
3292 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3293     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3294     if (!conn){
3295         log_info("gap_connect: no connection exists yet, creating context");
3296         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3297         if (!conn){
3298             // notify client that alloc failed
3299             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3300             log_info("gap_connect: failed to alloc hci_connection_t");
3301             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3302         }
3303         conn->state = SEND_CREATE_CONNECTION;
3304         log_info("gap_connect: send create connection next");
3305         hci_run();
3306         return 0;
3307     }
3308 
3309     if (!hci_is_le_connection(conn) ||
3310         conn->state == SEND_CREATE_CONNECTION ||
3311         conn->state == SENT_CREATE_CONNECTION) {
3312         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3313         log_error("gap_connect: classic connection or connect is already being created");
3314         return GATT_CLIENT_IN_WRONG_STATE;
3315     }
3316 
3317     log_info("gap_connect: context exists with state %u", conn->state);
3318     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3319     hci_run();
3320     return 0;
3321 }
3322 
3323 // @assumption: only a single outgoing LE Connection exists
3324 static hci_connection_t * gap_get_outgoing_connection(void){
3325     btstack_linked_item_t *it;
3326     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3327         hci_connection_t * conn = (hci_connection_t *) it;
3328         if (!hci_is_le_connection(conn)) continue;
3329         switch (conn->state){
3330             case SEND_CREATE_CONNECTION:
3331             case SENT_CREATE_CONNECTION:
3332                 return conn;
3333             default:
3334                 break;
3335         };
3336     }
3337     return NULL;
3338 }
3339 
3340 uint8_t gap_connect_cancel(void){
3341     hci_connection_t * conn = gap_get_outgoing_connection();
3342     if (!conn) return 0;
3343     switch (conn->state){
3344         case SEND_CREATE_CONNECTION:
3345             // skip sending create connection and emit event instead
3346             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3347             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3348             btstack_memory_hci_connection_free( conn );
3349             break;
3350         case SENT_CREATE_CONNECTION:
3351             // request to send cancel connection
3352             conn->state = SEND_CANCEL_CONNECTION;
3353             hci_run();
3354             break;
3355         default:
3356             break;
3357     }
3358     return 0;
3359 }
3360 
3361 /**
3362  * @brief Updates the connection parameters for a given LE connection
3363  * @param handle
3364  * @param conn_interval_min (unit: 1.25ms)
3365  * @param conn_interval_max (unit: 1.25ms)
3366  * @param conn_latency
3367  * @param supervision_timeout (unit: 10ms)
3368  * @returns 0 if ok
3369  */
3370 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3371     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3372     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3373     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3374     connection->le_conn_interval_min = conn_interval_min;
3375     connection->le_conn_interval_max = conn_interval_max;
3376     connection->le_conn_latency = conn_latency;
3377     connection->le_supervision_timeout = supervision_timeout;
3378     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3379     hci_run();
3380     return 0;
3381 }
3382 
3383 /**
3384  * @brief Request an update of the connection parameter for a given LE connection
3385  * @param handle
3386  * @param conn_interval_min (unit: 1.25ms)
3387  * @param conn_interval_max (unit: 1.25ms)
3388  * @param conn_latency
3389  * @param supervision_timeout (unit: 10ms)
3390  * @returns 0 if ok
3391  */
3392 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3393     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3394     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3395     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3396     connection->le_conn_interval_min = conn_interval_min;
3397     connection->le_conn_interval_max = conn_interval_max;
3398     connection->le_conn_latency = conn_latency;
3399     connection->le_supervision_timeout = supervision_timeout;
3400     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3401     hci_run();
3402     return 0;
3403 }
3404 
3405 static void gap_advertisments_changed(void){
3406     // disable advertisements before updating adv, scan data, or adv params
3407     if (hci_stack->le_advertisements_active){
3408         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3409     }
3410     hci_run();
3411 }
3412 
3413 /**
3414  * @brief Set Advertisement Data
3415  * @param advertising_data_length
3416  * @param advertising_data (max 31 octets)
3417  * @note data is not copied, pointer has to stay valid
3418  */
3419 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3420     hci_stack->le_advertisements_data_len = advertising_data_length;
3421     hci_stack->le_advertisements_data = advertising_data;
3422     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3423     gap_advertisments_changed();
3424 }
3425 
3426 /**
3427  * @brief Set Scan Response Data
3428  * @param advertising_data_length
3429  * @param advertising_data (max 31 octets)
3430  * @note data is not copied, pointer has to stay valid
3431  */
3432 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3433     hci_stack->le_scan_response_data_len = scan_response_data_length;
3434     hci_stack->le_scan_response_data = scan_response_data;
3435     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3436     gap_advertisments_changed();
3437 }
3438 
3439 /**
3440  * @brief Set Advertisement Parameters
3441  * @param adv_int_min
3442  * @param adv_int_max
3443  * @param adv_type
3444  * @param own_address_type
3445  * @param direct_address_type
3446  * @param direct_address
3447  * @param channel_map
3448  * @param filter_policy
3449  *
3450  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3451  */
3452  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3453     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3454     uint8_t channel_map, uint8_t filter_policy) {
3455 
3456     hci_stack->le_advertisements_interval_min = adv_int_min;
3457     hci_stack->le_advertisements_interval_max = adv_int_max;
3458     hci_stack->le_advertisements_type = adv_type;
3459     hci_stack->le_advertisements_own_address_type = own_address_type;
3460     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3461     hci_stack->le_advertisements_channel_map = channel_map;
3462     hci_stack->le_advertisements_filter_policy = filter_policy;
3463     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3464 
3465     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3466     gap_advertisments_changed();
3467  }
3468 
3469 /**
3470  * @brief Enable/Disable Advertisements
3471  * @param enabled
3472  */
3473 void gap_advertisements_enable(int enabled){
3474     hci_stack->le_advertisements_enabled = enabled;
3475     if (enabled && !hci_stack->le_advertisements_active){
3476         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3477     }
3478     if (!enabled && hci_stack->le_advertisements_active){
3479         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3480     }
3481     hci_run();
3482 }
3483 
3484 
3485 uint8_t gap_disconnect(hci_con_handle_t handle){
3486     hci_connection_t * conn = hci_connection_for_handle(handle);
3487     if (!conn){
3488         hci_emit_disconnection_complete(handle, 0);
3489         return 0;
3490     }
3491     conn->state = SEND_DISCONNECT;
3492     hci_run();
3493     return 0;
3494 }
3495 
3496 /**
3497  * @brief Get connection type
3498  * @param con_handle
3499  * @result connection_type
3500  */
3501 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3502     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3503     if (!conn) return GAP_CONNECTION_INVALID;
3504     switch (conn->address_type){
3505         case BD_ADDR_TYPE_LE_PUBLIC:
3506         case BD_ADDR_TYPE_LE_RANDOM:
3507             return GAP_CONNECTION_LE;
3508         case BD_ADDR_TYPE_SCO:
3509             return GAP_CONNECTION_SCO;
3510         case BD_ADDR_TYPE_CLASSIC:
3511             return GAP_CONNECTION_ACL;
3512         default:
3513             return GAP_CONNECTION_INVALID;
3514     }
3515 }
3516 
3517 #ifdef ENABLE_BLE
3518 
3519 /**
3520  * @brief Auto Connection Establishment - Start Connecting to device
3521  * @param address_typ
3522  * @param address
3523  * @returns 0 if ok
3524  */
3525 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3526     // check capacity
3527     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3528     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3529     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3530     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3531     entry->address_type = address_type;
3532     memcpy(entry->address, address, 6);
3533     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3534     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3535     hci_run();
3536     return 0;
3537 }
3538 
3539 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3540     btstack_linked_list_iterator_t it;
3541     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3542     while (btstack_linked_list_iterator_has_next(&it)){
3543         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3544         if (entry->address_type != address_type) continue;
3545         if (memcmp(entry->address, address, 6) != 0) continue;
3546         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3547             // remove from controller if already present
3548             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3549             continue;
3550         }
3551         // direclty remove entry from whitelist
3552         btstack_linked_list_iterator_remove(&it);
3553         btstack_memory_whitelist_entry_free(entry);
3554     }
3555 }
3556 
3557 /**
3558  * @brief Auto Connection Establishment - Stop Connecting to device
3559  * @param address_typ
3560  * @param address
3561  * @returns 0 if ok
3562  */
3563 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3564     hci_remove_from_whitelist(address_type, address);
3565     hci_run();
3566     return 0;
3567 }
3568 
3569 /**
3570  * @brief Auto Connection Establishment - Stop everything
3571  * @note  Convenience function to stop all active auto connection attempts
3572  */
3573 void gap_auto_connection_stop_all(void){
3574     btstack_linked_list_iterator_t it;
3575     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3576     while (btstack_linked_list_iterator_has_next(&it)){
3577         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3578         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3579             // remove from controller if already present
3580             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3581             continue;
3582         }
3583         // directly remove entry from whitelist
3584         btstack_linked_list_iterator_remove(&it);
3585         btstack_memory_whitelist_entry_free(entry);
3586     }
3587     hci_run();
3588 }
3589 
3590 #endif
3591 
3592 /**
3593  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3594  */
3595 void hci_set_sco_voice_setting(uint16_t voice_setting){
3596     hci_stack->sco_voice_setting = voice_setting;
3597 }
3598 
3599 /**
3600  * @brief Get SCO Voice Setting
3601  * @return current voice setting
3602  */
3603 uint16_t hci_get_sco_voice_setting(void){
3604     return hci_stack->sco_voice_setting;
3605 }
3606 
3607 /** @brief Get SCO packet length for current SCO Voice setting
3608  *  @note  Using SCO packets of the exact length is required for USB transfer
3609  *  @return Length of SCO packets in bytes (not audio frames)
3610  */
3611 int hci_get_sco_packet_length(void){
3612     // see Core Spec for H2 USB Transfer.
3613     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3614     return 27;
3615 }
3616 
3617 /**
3618  * @brief Set callback for Bluetooth Hardware Error
3619  */
3620 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
3621     hci_stack->hardware_error_callback = fn;
3622 }
3623 
3624 /**
3625  * @brief Set callback for local information from Bluetooth controller right after HCI Reset
3626  * @note Can be used to select chipset driver dynamically during startup
3627  */
3628 void hci_set_local_version_information_callback(void (*fn)(uint8_t * local_version_information)){
3629     hci_stack->local_version_information_callback = fn;
3630 }
3631 
3632 void hci_disconnect_all(void){
3633     btstack_linked_list_iterator_t it;
3634     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3635     while (btstack_linked_list_iterator_has_next(&it)){
3636         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3637         if (con->state == SENT_DISCONNECT) continue;
3638         con->state = SEND_DISCONNECT;
3639     }
3640     hci_run();
3641 }
3642