xref: /btstack/src/hci.c (revision 313e5f9c034d7b1fa958b7d42987533591c3cc61)
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)();
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     // max acl payload size defined in config.h
1980     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1981 
1982     // register packet handlers with transport
1983     transport->register_packet_handler(&packet_handler);
1984 
1985     hci_stack->state = HCI_STATE_OFF;
1986 
1987     // class of device
1988     hci_stack->class_of_device = 0x007a020c; // Smartphone
1989 
1990     // bondable by default
1991     hci_stack->bondable = 1;
1992 
1993     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
1994     hci_stack->ssp_enable = 1;
1995     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
1996     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
1997     hci_stack->ssp_auto_accept = 1;
1998 
1999     // voice setting - signed 8 bit pcm data with CVSD over the air
2000     hci_stack->sco_voice_setting = 0x40;
2001 
2002     hci_state_reset();
2003 }
2004 
2005 /**
2006  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2007  */
2008 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2009     hci_stack->chipset = chipset_driver;
2010 
2011     // reset chipset driver - init is also called on power_up
2012     if (hci_stack->chipset && hci_stack->chipset->init){
2013         hci_stack->chipset->init(hci_stack->config);
2014     }
2015 }
2016 
2017 /**
2018  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2019  */
2020 void hci_set_control(const btstack_control_t *hardware_control){
2021     // references to used control implementation
2022     hci_stack->control = hardware_control;
2023     // init with transport config
2024     hardware_control->init(hci_stack->config);
2025 }
2026 
2027 void hci_close(void){
2028     // close remote device db
2029     if (hci_stack->link_key_db) {
2030         hci_stack->link_key_db->close();
2031     }
2032 
2033     btstack_linked_list_iterator_t lit;
2034     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2035     while (btstack_linked_list_iterator_has_next(&lit)){
2036         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2037         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2038         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2039         hci_shutdown_connection(connection);
2040     }
2041 
2042     hci_power_control(HCI_POWER_OFF);
2043 
2044 #ifdef HAVE_MALLOC
2045     free(hci_stack);
2046 #endif
2047     hci_stack = NULL;
2048 }
2049 
2050 void gap_set_class_of_device(uint32_t class_of_device){
2051     hci_stack->class_of_device = class_of_device;
2052 }
2053 
2054 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2055 void hci_set_bd_addr(bd_addr_t addr){
2056     memcpy(hci_stack->custom_bd_addr, addr, 6);
2057     hci_stack->custom_bd_addr_set = 1;
2058 }
2059 
2060 void hci_disable_l2cap_timeout_check(void){
2061     disable_l2cap_timeouts = 1;
2062 }
2063 // State-Module-Driver overview
2064 // state                    module  low-level
2065 // HCI_STATE_OFF             off      close
2066 // HCI_STATE_INITIALIZING,   on       open
2067 // HCI_STATE_WORKING,        on       open
2068 // HCI_STATE_HALTING,        on       open
2069 // HCI_STATE_SLEEPING,    off/sleep   close
2070 // HCI_STATE_FALLING_ASLEEP  on       open
2071 
2072 static int hci_power_control_on(void){
2073 
2074     // power on
2075     int err = 0;
2076     if (hci_stack->control && hci_stack->control->on){
2077         err = (*hci_stack->control->on)();
2078     }
2079     if (err){
2080         log_error( "POWER_ON failed");
2081         hci_emit_hci_open_failed();
2082         return err;
2083     }
2084 
2085     // int chipset driver
2086     if (hci_stack->chipset && hci_stack->chipset->init){
2087         hci_stack->chipset->init(hci_stack->config);
2088     }
2089 
2090     // init transport
2091     if (hci_stack->hci_transport->init){
2092         hci_stack->hci_transport->init(hci_stack->config);
2093     }
2094 
2095     // open transport
2096     err = hci_stack->hci_transport->open();
2097     if (err){
2098         log_error( "HCI_INIT failed, turning Bluetooth off again");
2099         if (hci_stack->control && hci_stack->control->off){
2100             (*hci_stack->control->off)();
2101         }
2102         hci_emit_hci_open_failed();
2103         return err;
2104     }
2105     return 0;
2106 }
2107 
2108 static void hci_power_control_off(void){
2109 
2110     log_info("hci_power_control_off");
2111 
2112     // close low-level device
2113     hci_stack->hci_transport->close();
2114 
2115     log_info("hci_power_control_off - hci_transport closed");
2116 
2117     // power off
2118     if (hci_stack->control && hci_stack->control->off){
2119         (*hci_stack->control->off)();
2120     }
2121 
2122     log_info("hci_power_control_off - control closed");
2123 
2124     hci_stack->state = HCI_STATE_OFF;
2125 }
2126 
2127 static void hci_power_control_sleep(void){
2128 
2129     log_info("hci_power_control_sleep");
2130 
2131 #if 0
2132     // don't close serial port during sleep
2133 
2134     // close low-level device
2135     hci_stack->hci_transport->close(hci_stack->config);
2136 #endif
2137 
2138     // sleep mode
2139     if (hci_stack->control && hci_stack->control->sleep){
2140         (*hci_stack->control->sleep)();
2141     }
2142 
2143     hci_stack->state = HCI_STATE_SLEEPING;
2144 }
2145 
2146 static int hci_power_control_wake(void){
2147 
2148     log_info("hci_power_control_wake");
2149 
2150     // wake on
2151     if (hci_stack->control && hci_stack->control->wake){
2152         (*hci_stack->control->wake)();
2153     }
2154 
2155 #if 0
2156     // open low-level device
2157     int err = hci_stack->hci_transport->open(hci_stack->config);
2158     if (err){
2159         log_error( "HCI_INIT failed, turning Bluetooth off again");
2160         if (hci_stack->control && hci_stack->control->off){
2161             (*hci_stack->control->off)();
2162         }
2163         hci_emit_hci_open_failed();
2164         return err;
2165     }
2166 #endif
2167 
2168     return 0;
2169 }
2170 
2171 static void hci_power_transition_to_initializing(void){
2172     // set up state machine
2173     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
2174     hci_stack->hci_packet_buffer_reserved = 0;
2175     hci_stack->state = HCI_STATE_INITIALIZING;
2176     hci_stack->substate = HCI_INIT_SEND_RESET;
2177 }
2178 
2179 int hci_power_control(HCI_POWER_MODE power_mode){
2180 
2181     log_info("hci_power_control: %u, current mode %u", power_mode, hci_stack->state);
2182 
2183     int err = 0;
2184     switch (hci_stack->state){
2185 
2186         case HCI_STATE_OFF:
2187             switch (power_mode){
2188                 case HCI_POWER_ON:
2189                     err = hci_power_control_on();
2190                     if (err) {
2191                         log_error("hci_power_control_on() error %u", err);
2192                         return err;
2193                     }
2194                     hci_power_transition_to_initializing();
2195                     break;
2196                 case HCI_POWER_OFF:
2197                     // do nothing
2198                     break;
2199                 case HCI_POWER_SLEEP:
2200                     // do nothing (with SLEEP == OFF)
2201                     break;
2202             }
2203             break;
2204 
2205         case HCI_STATE_INITIALIZING:
2206             switch (power_mode){
2207                 case HCI_POWER_ON:
2208                     // do nothing
2209                     break;
2210                 case HCI_POWER_OFF:
2211                     // no connections yet, just turn it off
2212                     hci_power_control_off();
2213                     break;
2214                 case HCI_POWER_SLEEP:
2215                     // no connections yet, just turn it off
2216                     hci_power_control_sleep();
2217                     break;
2218             }
2219             break;
2220 
2221         case HCI_STATE_WORKING:
2222             switch (power_mode){
2223                 case HCI_POWER_ON:
2224                     // do nothing
2225                     break;
2226                 case HCI_POWER_OFF:
2227                     // see hci_run
2228                     hci_stack->state = HCI_STATE_HALTING;
2229                     break;
2230                 case HCI_POWER_SLEEP:
2231                     // see hci_run
2232                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2233                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2234                     break;
2235             }
2236             break;
2237 
2238         case HCI_STATE_HALTING:
2239             switch (power_mode){
2240                 case HCI_POWER_ON:
2241                     hci_power_transition_to_initializing();
2242                     break;
2243                 case HCI_POWER_OFF:
2244                     // do nothing
2245                     break;
2246                 case HCI_POWER_SLEEP:
2247                     // see hci_run
2248                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
2249                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
2250                     break;
2251             }
2252             break;
2253 
2254         case HCI_STATE_FALLING_ASLEEP:
2255             switch (power_mode){
2256                 case HCI_POWER_ON:
2257 
2258 #ifdef HAVE_PLATFORM_IPHONE_OS
2259                     // nothing to do, if H4 supports power management
2260                     if (btstack_control_iphone_power_management_enabled()){
2261                         hci_stack->state = HCI_STATE_INITIALIZING;
2262                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
2263                         break;
2264                     }
2265 #endif
2266                     hci_power_transition_to_initializing();
2267                     break;
2268                 case HCI_POWER_OFF:
2269                     // see hci_run
2270                     hci_stack->state = HCI_STATE_HALTING;
2271                     break;
2272                 case HCI_POWER_SLEEP:
2273                     // do nothing
2274                     break;
2275             }
2276             break;
2277 
2278         case HCI_STATE_SLEEPING:
2279             switch (power_mode){
2280                 case HCI_POWER_ON:
2281 
2282 #ifdef HAVE_PLATFORM_IPHONE_OS
2283                     // nothing to do, if H4 supports power management
2284                     if (btstack_control_iphone_power_management_enabled()){
2285                         hci_stack->state = HCI_STATE_INITIALIZING;
2286                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
2287                         hci_update_scan_enable();
2288                         break;
2289                     }
2290 #endif
2291                     err = hci_power_control_wake();
2292                     if (err) return err;
2293                     hci_power_transition_to_initializing();
2294                     break;
2295                 case HCI_POWER_OFF:
2296                     hci_stack->state = HCI_STATE_HALTING;
2297                     break;
2298                 case HCI_POWER_SLEEP:
2299                     // do nothing
2300                     break;
2301             }
2302             break;
2303     }
2304 
2305     // create internal event
2306 	hci_emit_state();
2307 
2308 	// trigger next/first action
2309 	hci_run();
2310 
2311     return 0;
2312 }
2313 
2314 static void hci_update_scan_enable(void){
2315     // 2 = page scan, 1 = inq scan
2316     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
2317     hci_run();
2318 }
2319 
2320 void gap_discoverable_control(uint8_t enable){
2321     if (enable) enable = 1; // normalize argument
2322 
2323     if (hci_stack->discoverable == enable){
2324         hci_emit_discoverable_enabled(hci_stack->discoverable);
2325         return;
2326     }
2327 
2328     hci_stack->discoverable = enable;
2329     hci_update_scan_enable();
2330 }
2331 
2332 void gap_connectable_control(uint8_t enable){
2333     if (enable) enable = 1; // normalize argument
2334 
2335     // don't emit event
2336     if (hci_stack->connectable == enable) return;
2337 
2338     hci_stack->connectable = enable;
2339     hci_update_scan_enable();
2340 }
2341 
2342 void gap_local_bd_addr(bd_addr_t address_buffer){
2343     memcpy(address_buffer, hci_stack->local_bd_addr, 6);
2344 }
2345 
2346 static void hci_run(void){
2347 
2348     // log_info("hci_run: entered");
2349     btstack_linked_item_t * it;
2350 
2351     // send continuation fragments first, as they block the prepared packet buffer
2352     if (hci_stack->acl_fragmentation_total_size > 0) {
2353         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
2354         if (hci_can_send_prepared_acl_packet_now(con_handle)){
2355             hci_connection_t *connection = hci_connection_for_handle(con_handle);
2356             if (connection) {
2357                 hci_send_acl_packet_fragments(connection);
2358                 return;
2359             }
2360             // connection gone -> discard further fragments
2361             hci_stack->acl_fragmentation_total_size = 0;
2362             hci_stack->acl_fragmentation_pos = 0;
2363         }
2364     }
2365 
2366     if (!hci_can_send_command_packet_now()) return;
2367 
2368     // global/non-connection oriented commands
2369 
2370     // decline incoming connections
2371     if (hci_stack->decline_reason){
2372         uint8_t reason = hci_stack->decline_reason;
2373         hci_stack->decline_reason = 0;
2374         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
2375         return;
2376     }
2377 
2378     // send scan enable
2379     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
2380         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
2381         hci_stack->new_scan_enable_value = 0xff;
2382         return;
2383     }
2384 
2385 #ifdef ENABLE_BLE
2386     if (hci_stack->state == HCI_STATE_WORKING){
2387         // handle le scan
2388         switch(hci_stack->le_scanning_state){
2389             case LE_START_SCAN:
2390                 hci_stack->le_scanning_state = LE_SCANNING;
2391                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
2392                 return;
2393 
2394             case LE_STOP_SCAN:
2395                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
2396                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
2397                 return;
2398             default:
2399                 break;
2400         }
2401         if (hci_stack->le_scan_type != 0xff){
2402             // defaults: active scanning, accept all advertisement packets
2403             int scan_type = hci_stack->le_scan_type;
2404             hci_stack->le_scan_type = 0xff;
2405             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);
2406             return;
2407         }
2408         // le advertisement control
2409         if (hci_stack->le_advertisements_todo){
2410             log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
2411         }
2412         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
2413             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
2414             hci_send_cmd(&hci_le_set_advertise_enable, 0);
2415             return;
2416         }
2417         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
2418             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
2419             hci_send_cmd(&hci_le_set_advertising_parameters,
2420                  hci_stack->le_advertisements_interval_min,
2421                  hci_stack->le_advertisements_interval_max,
2422                  hci_stack->le_advertisements_type,
2423                  hci_stack->le_advertisements_own_address_type,
2424                  hci_stack->le_advertisements_direct_address_type,
2425                  hci_stack->le_advertisements_direct_address,
2426                  hci_stack->le_advertisements_channel_map,
2427                  hci_stack->le_advertisements_filter_policy);
2428             return;
2429         }
2430         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
2431             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
2432             hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len,
2433                 hci_stack->le_advertisements_data);
2434             return;
2435         }
2436         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
2437             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
2438             hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len,
2439                 hci_stack->le_scan_response_data);
2440             return;
2441         }
2442         if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
2443             hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
2444             hci_send_cmd(&hci_le_set_advertise_enable, 1);
2445             return;
2446         }
2447 
2448         //
2449         // LE Whitelist Management
2450         //
2451 
2452         // check if whitelist needs modification
2453         btstack_linked_list_iterator_t lit;
2454         int modification_pending = 0;
2455         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2456         while (btstack_linked_list_iterator_has_next(&lit)){
2457             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2458             if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
2459                 modification_pending = 1;
2460                 break;
2461             }
2462         }
2463 
2464         if (modification_pending){
2465             // stop connnecting if modification pending
2466             if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
2467                 hci_send_cmd(&hci_le_create_connection_cancel);
2468                 return;
2469             }
2470 
2471             // add/remove entries
2472             btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2473             while (btstack_linked_list_iterator_has_next(&lit)){
2474                 whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2475                 if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
2476                     entry->state = LE_WHITELIST_ON_CONTROLLER;
2477                     hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
2478                     return;
2479 
2480                 }
2481                 if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
2482                     bd_addr_t address;
2483                     bd_addr_type_t address_type = entry->address_type;
2484                     memcpy(address, entry->address, 6);
2485                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2486                     btstack_memory_whitelist_entry_free(entry);
2487                     hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
2488                     return;
2489                 }
2490             }
2491         }
2492 
2493         // start connecting
2494         if ( hci_stack->le_connecting_state == LE_CONNECTING_IDLE &&
2495             !btstack_linked_list_empty(&hci_stack->le_whitelist)){
2496             bd_addr_t null_addr;
2497             memset(null_addr, 0, 6);
2498             hci_send_cmd(&hci_le_create_connection,
2499                  0x0060,    // scan interval: 60 ms
2500                  0x0030,    // scan interval: 30 ms
2501                  1,         // use whitelist
2502                  0,         // peer address type
2503                  null_addr,      // peer bd addr
2504                  hci_stack->adv_addr_type, // our addr type:
2505                  0x0008,    // conn interval min
2506                  0x0018,    // conn interval max
2507                  0,         // conn latency
2508                  0x0048,    // supervision timeout
2509                  0x0001,    // min ce length
2510                  0x0001     // max ce length
2511                  );
2512             return;
2513         }
2514     }
2515 #endif
2516 
2517     // send pending HCI commands
2518     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
2519         hci_connection_t * connection = (hci_connection_t *) it;
2520 
2521         switch(connection->state){
2522             case SEND_CREATE_CONNECTION:
2523                 switch(connection->address_type){
2524                     case BD_ADDR_TYPE_CLASSIC:
2525                         log_info("sending hci_create_connection");
2526                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
2527                         break;
2528                     default:
2529 #ifdef ENABLE_BLE
2530                         log_info("sending hci_le_create_connection");
2531                         hci_send_cmd(&hci_le_create_connection,
2532                                      0x0060,    // scan interval: 60 ms
2533                                      0x0030,    // scan interval: 30 ms
2534                                      0,         // don't use whitelist
2535                                      connection->address_type, // peer address type
2536                                      connection->address,      // peer bd addr
2537                                      hci_stack->adv_addr_type, // our addr type:
2538                                      0x0008,    // conn interval min
2539                                      0x0018,    // conn interval max
2540                                      0,         // conn latency
2541                                      0x0048,    // supervision timeout
2542                                      0x0001,    // min ce length
2543                                      0x0001     // max ce length
2544                                      );
2545 
2546                         connection->state = SENT_CREATE_CONNECTION;
2547 #endif
2548                         break;
2549                 }
2550                 return;
2551 
2552             case RECEIVED_CONNECTION_REQUEST:
2553                 log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
2554                 connection->state = ACCEPTED_CONNECTION_REQUEST;
2555                 connection->role  = HCI_ROLE_SLAVE;
2556                 if (connection->address_type == BD_ADDR_TYPE_CLASSIC){
2557                     hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
2558                 } else {
2559                     // remote supported feature eSCO is set if link type is eSCO
2560                     uint16_t max_latency;
2561                     uint8_t  retransmission_effort;
2562                     uint16_t packet_types;
2563                     // remote supported feature eSCO is set if link type is eSCO
2564                     if (connection->remote_supported_feature_eSCO){
2565                         // eSCO: S4 - max latency == transmission interval = 0x000c == 12 ms,
2566                         max_latency = 0x000c;
2567                         retransmission_effort = 0x02;
2568                         packet_types = 0x388;
2569                     } else {
2570                         // SCO: max latency, retransmission interval: N/A. any packet type
2571                         max_latency = 0xffff;
2572                         retransmission_effort = 0xff;
2573                         packet_types = 0x003f;
2574                     }
2575                     hci_send_cmd(&hci_accept_synchronous_connection, connection->address, 8000, 8000, max_latency, hci_stack->sco_voice_setting, retransmission_effort, packet_types);
2576                 }
2577                 return;
2578 
2579 #ifdef ENABLE_BLE
2580             case SEND_CANCEL_CONNECTION:
2581                 connection->state = SENT_CANCEL_CONNECTION;
2582                 hci_send_cmd(&hci_le_create_connection_cancel);
2583                 return;
2584 #endif
2585             case SEND_DISCONNECT:
2586                 connection->state = SENT_DISCONNECT;
2587                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
2588                 return;
2589 
2590             default:
2591                 break;
2592         }
2593 
2594         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
2595             log_info("responding to link key request");
2596             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
2597             link_key_t link_key;
2598             link_key_type_t link_key_type;
2599             if ( hci_stack->link_key_db
2600               && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
2601               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
2602                connection->link_key_type = link_key_type;
2603                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
2604             } else {
2605                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
2606             }
2607             return;
2608         }
2609 
2610         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
2611             log_info("denying to pin request");
2612             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
2613             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
2614             return;
2615         }
2616 
2617         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
2618             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
2619             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
2620             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
2621                 // tweak authentication requirements
2622                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
2623                 if (connection->bonding_flags & BONDING_DEDICATED){
2624                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2625                 }
2626                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
2627                     authreq |= 1;
2628                 }
2629                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
2630             } else {
2631                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
2632             }
2633             return;
2634         }
2635 
2636         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
2637             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
2638             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
2639             return;
2640         }
2641 
2642         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
2643             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
2644             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
2645             return;
2646         }
2647 
2648         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
2649             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
2650             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
2651             return;
2652         }
2653 
2654         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
2655             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
2656             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
2657             return;
2658         }
2659         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
2660             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
2661             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
2662             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
2663             return;
2664         }
2665         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
2666             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
2667             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
2668             return;
2669         }
2670         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
2671             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
2672             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
2673             return;
2674         }
2675 
2676 #ifdef ENABLE_BLE
2677         if (connection->le_con_parameter_update_state == CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS){
2678             connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
2679 
2680             uint16_t connection_interval_min = connection->le_conn_interval_min;
2681             connection->le_conn_interval_min = 0;
2682             hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection_interval_min,
2683                 connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
2684                 0x0000, 0xffff);
2685         }
2686 #endif
2687     }
2688 
2689     hci_connection_t * connection;
2690     switch (hci_stack->state){
2691         case HCI_STATE_INITIALIZING:
2692             hci_initializing_run();
2693             break;
2694 
2695         case HCI_STATE_HALTING:
2696 
2697             log_info("HCI_STATE_HALTING");
2698 
2699             // free whitelist entries
2700 #ifdef ENABLE_BLE
2701             {
2702                 btstack_linked_list_iterator_t lit;
2703                 btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
2704                 while (btstack_linked_list_iterator_has_next(&lit)){
2705                     whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
2706                     btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
2707                     btstack_memory_whitelist_entry_free(entry);
2708                 }
2709             }
2710 #endif
2711             // close all open connections
2712             connection =  (hci_connection_t *) hci_stack->connections;
2713             if (connection){
2714                 hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
2715                 if (!hci_can_send_command_packet_now()) return;
2716 
2717                 log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
2718 
2719                 // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
2720                 hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
2721 
2722                 // ... which would be ignored anyway as we shutdown (free) the connection now
2723                 hci_shutdown_connection(connection);
2724 
2725                 // finally, send the disconnect command
2726                 hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
2727                 return;
2728             }
2729             log_info("HCI_STATE_HALTING, calling off");
2730 
2731             // switch mode
2732             hci_power_control_off();
2733 
2734             log_info("HCI_STATE_HALTING, emitting state");
2735             hci_emit_state();
2736             log_info("HCI_STATE_HALTING, done");
2737             break;
2738 
2739         case HCI_STATE_FALLING_ASLEEP:
2740             switch(hci_stack->substate) {
2741                 case HCI_FALLING_ASLEEP_DISCONNECT:
2742                     log_info("HCI_STATE_FALLING_ASLEEP");
2743                     // close all open connections
2744                     connection =  (hci_connection_t *) hci_stack->connections;
2745 
2746 #ifdef HAVE_PLATFORM_IPHONE_OS
2747                     // don't close connections, if H4 supports power management
2748                     if (btstack_control_iphone_power_management_enabled()){
2749                         connection = NULL;
2750                     }
2751 #endif
2752                     if (connection){
2753 
2754                         // send disconnect
2755                         if (!hci_can_send_command_packet_now()) return;
2756 
2757                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
2758                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
2759 
2760                         // send disconnected event right away - causes higher layer connections to get closed, too.
2761                         hci_shutdown_connection(connection);
2762                         return;
2763                     }
2764 
2765                     if (hci_classic_supported()){
2766                         // disable page and inquiry scan
2767                         if (!hci_can_send_command_packet_now()) return;
2768 
2769                         log_info("HCI_STATE_HALTING, disabling inq scans");
2770                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
2771 
2772                         // continue in next sub state
2773                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
2774                         break;
2775                     }
2776                     // fall through for ble-only chips
2777 
2778                 case HCI_FALLING_ASLEEP_COMPLETE:
2779                     log_info("HCI_STATE_HALTING, calling sleep");
2780 #ifdef HAVE_PLATFORM_IPHONE_OS
2781                     // don't actually go to sleep, if H4 supports power management
2782                     if (btstack_control_iphone_power_management_enabled()){
2783                         // SLEEP MODE reached
2784                         hci_stack->state = HCI_STATE_SLEEPING;
2785                         hci_emit_state();
2786                         break;
2787                     }
2788 #endif
2789                     // switch mode
2790                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
2791                     hci_emit_state();
2792                     break;
2793 
2794                 default:
2795                     break;
2796             }
2797             break;
2798 
2799         default:
2800             break;
2801     }
2802 }
2803 
2804 int hci_send_cmd_packet(uint8_t *packet, int size){
2805     bd_addr_t addr;
2806     hci_connection_t * conn;
2807     // house-keeping
2808 
2809     // create_connection?
2810     if (IS_COMMAND(packet, hci_create_connection)){
2811         reverse_bd_addr(&packet[3], addr);
2812         log_info("Create_connection to %s", bd_addr_to_str(addr));
2813 
2814         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2815         if (!conn){
2816             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2817             if (!conn){
2818                 // notify client that alloc failed
2819                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
2820                 return 0; // don't sent packet to controller
2821             }
2822             conn->state = SEND_CREATE_CONNECTION;
2823         }
2824         log_info("conn state %u", conn->state);
2825         switch (conn->state){
2826             // if connection active exists
2827             case OPEN:
2828                 // and OPEN, emit connection complete command, don't send to controller
2829                 hci_emit_connection_complete(addr, conn->con_handle, 0);
2830                 return 0;
2831             case SEND_CREATE_CONNECTION:
2832                 // connection created by hci, e.g. dedicated bonding
2833                 break;
2834             default:
2835                 // otherwise, just ignore as it is already in the open process
2836                 return 0;
2837         }
2838         conn->state = SENT_CREATE_CONNECTION;
2839     }
2840     if (IS_COMMAND(packet, hci_link_key_request_reply)){
2841         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
2842     }
2843     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
2844         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
2845     }
2846 
2847     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
2848         if (hci_stack->link_key_db){
2849             reverse_bd_addr(&packet[3], addr);
2850             hci_stack->link_key_db->delete_link_key(addr);
2851         }
2852     }
2853 
2854     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
2855     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
2856         reverse_bd_addr(&packet[3], addr);
2857         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2858         if (conn){
2859             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
2860         }
2861     }
2862 
2863     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
2864     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
2865     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
2866     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
2867         reverse_bd_addr(&packet[3], addr);
2868         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
2869         if (conn){
2870             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
2871         }
2872     }
2873 
2874     if (IS_COMMAND(packet, hci_write_loopback_mode)){
2875         hci_stack->loopback_mode = packet[3];
2876     }
2877 
2878 #ifdef ENABLE_BLE
2879     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
2880         hci_stack->adv_addr_type = packet[8];
2881     }
2882     if (IS_COMMAND(packet, hci_le_set_random_address)){
2883         reverse_bd_addr(&packet[3], hci_stack->adv_address);
2884     }
2885     if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
2886         hci_stack->le_advertisements_active = packet[3];
2887     }
2888     if (IS_COMMAND(packet, hci_le_create_connection)){
2889         // white list used?
2890         uint8_t initiator_filter_policy = packet[7];
2891         switch (initiator_filter_policy){
2892             case 0:
2893                 // whitelist not used
2894                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
2895                 break;
2896             case 1:
2897                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
2898                 break;
2899             default:
2900                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
2901                 break;
2902         }
2903     }
2904     if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
2905         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2906     }
2907 #endif
2908 
2909     hci_stack->num_cmd_packets--;
2910 
2911     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
2912     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
2913 
2914     // release packet buffer for synchronous transport implementations
2915     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
2916         hci_stack->hci_packet_buffer_reserved = 0;
2917     }
2918 
2919     return err;
2920 }
2921 
2922 // disconnect because of security block
2923 void hci_disconnect_security_block(hci_con_handle_t con_handle){
2924     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2925     if (!connection) return;
2926     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2927 }
2928 
2929 
2930 // Configure Secure Simple Pairing
2931 
2932 // enable will enable SSP during init
2933 void gap_ssp_set_enable(int enable){
2934     hci_stack->ssp_enable = enable;
2935 }
2936 
2937 static int hci_local_ssp_activated(void){
2938     return gap_ssp_supported() && hci_stack->ssp_enable;
2939 }
2940 
2941 // if set, BTstack will respond to io capability request using authentication requirement
2942 void gap_ssp_set_io_capability(int io_capability){
2943     hci_stack->ssp_io_capability = io_capability;
2944 }
2945 void gap_ssp_set_authentication_requirement(int authentication_requirement){
2946     hci_stack->ssp_authentication_requirement = authentication_requirement;
2947 }
2948 
2949 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
2950 void gap_ssp_set_auto_accept(int auto_accept){
2951     hci_stack->ssp_auto_accept = auto_accept;
2952 }
2953 
2954 /**
2955  * pre: numcmds >= 0 - it's allowed to send a command to the controller
2956  */
2957 int hci_send_cmd(const hci_cmd_t *cmd, ...){
2958 
2959     if (!hci_can_send_command_packet_now()){
2960         log_error("hci_send_cmd called but cannot send packet now");
2961         return 0;
2962     }
2963 
2964     // for HCI INITIALIZATION
2965     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
2966     hci_stack->last_cmd_opcode = cmd->opcode;
2967 
2968     hci_reserve_packet_buffer();
2969     uint8_t * packet = hci_stack->hci_packet_buffer;
2970 
2971     va_list argptr;
2972     va_start(argptr, cmd);
2973     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
2974     va_end(argptr);
2975 
2976     return hci_send_cmd_packet(packet, size);
2977 }
2978 
2979 // Create various non-HCI events.
2980 // TODO: generalize, use table similar to hci_create_command
2981 
2982 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
2983     // dump packet
2984     if (dump) {
2985         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
2986     }
2987 
2988     // dispatch to all event handlers
2989     btstack_linked_list_iterator_t it;
2990     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
2991     while (btstack_linked_list_iterator_has_next(&it)){
2992         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
2993         entry->callback(HCI_EVENT_PACKET, 0, event, size);
2994     }
2995 }
2996 
2997 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
2998     if (!hci_stack->acl_packet_handler) return;
2999     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
3000 }
3001 
3002 static void hci_notify_if_sco_can_send_now(void){
3003     // notify SCO sender if waiting
3004     if (!hci_stack->sco_waiting_for_can_send_now) return;
3005     if (hci_can_send_sco_packet_now()){
3006         hci_stack->sco_waiting_for_can_send_now = 0;
3007         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
3008         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
3009         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
3010     }
3011 }
3012 
3013 void hci_emit_state(void){
3014     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
3015     uint8_t event[3];
3016     event[0] = BTSTACK_EVENT_STATE;
3017     event[1] = sizeof(event) - 2;
3018     event[2] = hci_stack->state;
3019     hci_emit_event(event, sizeof(event), 1);
3020 }
3021 
3022 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3023     uint8_t event[13];
3024     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
3025     event[1] = sizeof(event) - 2;
3026     event[2] = status;
3027     little_endian_store_16(event, 3, con_handle);
3028     reverse_bd_addr(address, &event[5]);
3029     event[11] = 1; // ACL connection
3030     event[12] = 0; // encryption disabled
3031     hci_emit_event(event, sizeof(event), 1);
3032 }
3033 
3034 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
3035     uint8_t event[21];
3036     event[0] = HCI_EVENT_LE_META;
3037     event[1] = sizeof(event) - 2;
3038     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
3039     event[3] = status;
3040     little_endian_store_16(event, 4, con_handle);
3041     event[6] = 0; // TODO: role
3042     event[7] = address_type;
3043     reverse_bd_addr(address, &event[8]);
3044     little_endian_store_16(event, 14, 0); // interval
3045     little_endian_store_16(event, 16, 0); // latency
3046     little_endian_store_16(event, 18, 0); // supervision timeout
3047     event[20] = 0; // master clock accuracy
3048     hci_emit_event(event, sizeof(event), 1);
3049 }
3050 
3051 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
3052     uint8_t event[6];
3053     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
3054     event[1] = sizeof(event) - 2;
3055     event[2] = 0; // status = OK
3056     little_endian_store_16(event, 3, con_handle);
3057     event[5] = reason;
3058     hci_emit_event(event, sizeof(event), 1);
3059 }
3060 
3061 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
3062     if (disable_l2cap_timeouts) return;
3063     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
3064     uint8_t event[4];
3065     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
3066     event[1] = sizeof(event) - 2;
3067     little_endian_store_16(event, 2, conn->con_handle);
3068     hci_emit_event(event, sizeof(event), 1);
3069 }
3070 
3071 static void hci_emit_nr_connections_changed(void){
3072     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
3073     uint8_t event[3];
3074     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
3075     event[1] = sizeof(event) - 2;
3076     event[2] = nr_hci_connections();
3077     hci_emit_event(event, sizeof(event), 1);
3078 }
3079 
3080 static void hci_emit_hci_open_failed(void){
3081     log_info("BTSTACK_EVENT_POWERON_FAILED");
3082     uint8_t event[2];
3083     event[0] = BTSTACK_EVENT_POWERON_FAILED;
3084     event[1] = sizeof(event) - 2;
3085     hci_emit_event(event, sizeof(event), 1);
3086 }
3087 
3088 static void hci_emit_discoverable_enabled(uint8_t enabled){
3089     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
3090     uint8_t event[3];
3091     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
3092     event[1] = sizeof(event) - 2;
3093     event[2] = enabled;
3094     hci_emit_event(event, sizeof(event), 1);
3095 }
3096 
3097 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
3098     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
3099     uint8_t event[5];
3100     int pos = 0;
3101     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
3102     event[pos++] = sizeof(event) - 2;
3103     little_endian_store_16(event, 2, con_handle);
3104     pos += 2;
3105     event[pos++] = level;
3106     hci_emit_event(event, sizeof(event), 1);
3107 }
3108 
3109 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
3110     log_info("hci_emit_dedicated_bonding_result %u ", status);
3111     uint8_t event[9];
3112     int pos = 0;
3113     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
3114     event[pos++] = sizeof(event) - 2;
3115     event[pos++] = status;
3116     reverse_bd_addr(address, &event[pos]);
3117     hci_emit_event(event, sizeof(event), 1);
3118 }
3119 
3120 // query if remote side supports eSCO
3121 int hci_remote_esco_supported(hci_con_handle_t con_handle){
3122     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3123     if (!connection) return 0;
3124     return connection->remote_supported_feature_eSCO;
3125 }
3126 
3127 // query if remote side supports SSP
3128 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
3129     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3130     if (!connection) return 0;
3131     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
3132 }
3133 
3134 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
3135     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
3136 }
3137 
3138 // GAP API
3139 /**
3140  * @bbrief enable/disable bonding. default is enabled
3141  * @praram enabled
3142  */
3143 void gap_set_bondable_mode(int enable){
3144     hci_stack->bondable = enable ? 1 : 0;
3145 }
3146 /**
3147  * @brief Get bondable mode.
3148  * @return 1 if bondable
3149  */
3150 int gap_get_bondable_mode(void){
3151     return hci_stack->bondable;
3152 }
3153 
3154 /**
3155  * @brief map link keys to security levels
3156  */
3157 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
3158     switch (link_key_type){
3159         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
3160             return LEVEL_4;
3161         case COMBINATION_KEY:
3162         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
3163             return LEVEL_3;
3164         default:
3165             return LEVEL_2;
3166     }
3167 }
3168 
3169 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
3170     if (!connection) return LEVEL_0;
3171     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
3172     return gap_security_level_for_link_key_type(connection->link_key_type);
3173 }
3174 
3175 
3176 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
3177     log_info("gap_mitm_protection_required_for_security_level %u", level);
3178     return level > LEVEL_2;
3179 }
3180 
3181 /**
3182  * @brief get current security level
3183  */
3184 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
3185     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3186     if (!connection) return LEVEL_0;
3187     return gap_security_level_for_connection(connection);
3188 }
3189 
3190 /**
3191  * @brief request connection to device to
3192  * @result GAP_AUTHENTICATION_RESULT
3193  */
3194 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
3195     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3196     if (!connection){
3197         hci_emit_security_level(con_handle, LEVEL_0);
3198         return;
3199     }
3200     gap_security_level_t current_level = gap_security_level(con_handle);
3201     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
3202     if (current_level >= requested_level){
3203         hci_emit_security_level(con_handle, current_level);
3204         return;
3205     }
3206 
3207     connection->requested_security_level = requested_level;
3208 
3209 #if 0
3210     // sending encryption request without a link key results in an error.
3211     // TODO: figure out how to use it properly
3212 
3213     // would enabling ecnryption suffice (>= LEVEL_2)?
3214     if (hci_stack->link_key_db){
3215         link_key_type_t link_key_type;
3216         link_key_t      link_key;
3217         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
3218             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
3219                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3220                 return;
3221             }
3222         }
3223     }
3224 #endif
3225 
3226     // try to authenticate connection
3227     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
3228     hci_run();
3229 }
3230 
3231 /**
3232  * @brief start dedicated bonding with device. disconnect after bonding
3233  * @param device
3234  * @param request MITM protection
3235  * @result GAP_DEDICATED_BONDING_COMPLETE
3236  */
3237 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
3238 
3239     // create connection state machine
3240     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
3241 
3242     if (!connection){
3243         return BTSTACK_MEMORY_ALLOC_FAILED;
3244     }
3245 
3246     // delete linkn key
3247     gap_drop_link_key_for_bd_addr(device);
3248 
3249     // configure LEVEL_2/3, dedicated bonding
3250     connection->state = SEND_CREATE_CONNECTION;
3251     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
3252     log_info("gap_dedicated_bonding, mitm %u -> level %u", mitm_protection_required, connection->requested_security_level);
3253     connection->bonding_flags = BONDING_DEDICATED;
3254 
3255     // wait for GAP Security Result and send GAP Dedicated Bonding complete
3256 
3257     // handle: connnection failure (connection complete != ok)
3258     // handle: authentication failure
3259     // handle: disconnect on done
3260 
3261     hci_run();
3262 
3263     return 0;
3264 }
3265 
3266 void gap_set_local_name(const char * local_name){
3267     hci_stack->local_name = local_name;
3268 }
3269 
3270 void gap_start_scan(void){
3271     if (hci_stack->le_scanning_state == LE_SCANNING) return;
3272     hci_stack->le_scanning_state = LE_START_SCAN;
3273     hci_run();
3274 }
3275 
3276 void gap_stop_scan(void){
3277     if ( hci_stack->le_scanning_state == LE_SCAN_IDLE) return;
3278     hci_stack->le_scanning_state = LE_STOP_SCAN;
3279     hci_run();
3280 }
3281 
3282 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
3283     hci_stack->le_scan_type     = scan_type;
3284     hci_stack->le_scan_interval = scan_interval;
3285     hci_stack->le_scan_window   = scan_window;
3286     hci_run();
3287 }
3288 
3289 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
3290     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3291     if (!conn){
3292         log_info("gap_connect: no connection exists yet, creating context");
3293         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
3294         if (!conn){
3295             // notify client that alloc failed
3296             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
3297             log_info("gap_connect: failed to alloc hci_connection_t");
3298             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
3299         }
3300         conn->state = SEND_CREATE_CONNECTION;
3301         log_info("gap_connect: send create connection next");
3302         hci_run();
3303         return 0;
3304     }
3305 
3306     if (!hci_is_le_connection(conn) ||
3307         conn->state == SEND_CREATE_CONNECTION ||
3308         conn->state == SENT_CREATE_CONNECTION) {
3309         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
3310         log_error("gap_connect: classic connection or connect is already being created");
3311         return GATT_CLIENT_IN_WRONG_STATE;
3312     }
3313 
3314     log_info("gap_connect: context exists with state %u", conn->state);
3315     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
3316     hci_run();
3317     return 0;
3318 }
3319 
3320 // @assumption: only a single outgoing LE Connection exists
3321 static hci_connection_t * gap_get_outgoing_connection(void){
3322     btstack_linked_item_t *it;
3323     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3324         hci_connection_t * conn = (hci_connection_t *) it;
3325         if (!hci_is_le_connection(conn)) continue;
3326         switch (conn->state){
3327             case SEND_CREATE_CONNECTION:
3328             case SENT_CREATE_CONNECTION:
3329                 return conn;
3330             default:
3331                 break;
3332         };
3333     }
3334     return NULL;
3335 }
3336 
3337 uint8_t gap_connect_cancel(void){
3338     hci_connection_t * conn = gap_get_outgoing_connection();
3339     if (!conn) return 0;
3340     switch (conn->state){
3341         case SEND_CREATE_CONNECTION:
3342             // skip sending create connection and emit event instead
3343             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
3344             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
3345             btstack_memory_hci_connection_free( conn );
3346             break;
3347         case SENT_CREATE_CONNECTION:
3348             // request to send cancel connection
3349             conn->state = SEND_CANCEL_CONNECTION;
3350             hci_run();
3351             break;
3352         default:
3353             break;
3354     }
3355     return 0;
3356 }
3357 
3358 /**
3359  * @brief Updates the connection parameters for a given LE connection
3360  * @param handle
3361  * @param conn_interval_min (unit: 1.25ms)
3362  * @param conn_interval_max (unit: 1.25ms)
3363  * @param conn_latency
3364  * @param supervision_timeout (unit: 10ms)
3365  * @returns 0 if ok
3366  */
3367 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3368     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3369     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3370     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3371     connection->le_conn_interval_min = conn_interval_min;
3372     connection->le_conn_interval_max = conn_interval_max;
3373     connection->le_conn_latency = conn_latency;
3374     connection->le_supervision_timeout = supervision_timeout;
3375     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
3376     hci_run();
3377     return 0;
3378 }
3379 
3380 /**
3381  * @brief Request an update of the connection parameter for a given LE connection
3382  * @param handle
3383  * @param conn_interval_min (unit: 1.25ms)
3384  * @param conn_interval_max (unit: 1.25ms)
3385  * @param conn_latency
3386  * @param supervision_timeout (unit: 10ms)
3387  * @returns 0 if ok
3388  */
3389 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
3390     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
3391     hci_connection_t * connection = hci_connection_for_handle(con_handle);
3392     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
3393     connection->le_conn_interval_min = conn_interval_min;
3394     connection->le_conn_interval_max = conn_interval_max;
3395     connection->le_conn_latency = conn_latency;
3396     connection->le_supervision_timeout = supervision_timeout;
3397     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
3398     hci_run();
3399     return 0;
3400 }
3401 
3402 static void gap_advertisments_changed(void){
3403     // disable advertisements before updating adv, scan data, or adv params
3404     if (hci_stack->le_advertisements_active){
3405         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
3406     }
3407     hci_run();
3408 }
3409 
3410 /**
3411  * @brief Set Advertisement Data
3412  * @param advertising_data_length
3413  * @param advertising_data (max 31 octets)
3414  * @note data is not copied, pointer has to stay valid
3415  */
3416 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
3417     hci_stack->le_advertisements_data_len = advertising_data_length;
3418     hci_stack->le_advertisements_data = advertising_data;
3419     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3420     gap_advertisments_changed();
3421 }
3422 
3423 /**
3424  * @brief Set Scan Response Data
3425  * @param advertising_data_length
3426  * @param advertising_data (max 31 octets)
3427  * @note data is not copied, pointer has to stay valid
3428  */
3429 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
3430     hci_stack->le_scan_response_data_len = scan_response_data_length;
3431     hci_stack->le_scan_response_data = scan_response_data;
3432     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3433     gap_advertisments_changed();
3434 }
3435 
3436 /**
3437  * @brief Set Advertisement Parameters
3438  * @param adv_int_min
3439  * @param adv_int_max
3440  * @param adv_type
3441  * @param own_address_type
3442  * @param direct_address_type
3443  * @param direct_address
3444  * @param channel_map
3445  * @param filter_policy
3446  *
3447  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
3448  */
3449  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
3450     uint8_t own_address_type, uint8_t direct_address_typ, bd_addr_t direct_address,
3451     uint8_t channel_map, uint8_t filter_policy) {
3452 
3453     hci_stack->le_advertisements_interval_min = adv_int_min;
3454     hci_stack->le_advertisements_interval_max = adv_int_max;
3455     hci_stack->le_advertisements_type = adv_type;
3456     hci_stack->le_advertisements_own_address_type = own_address_type;
3457     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
3458     hci_stack->le_advertisements_channel_map = channel_map;
3459     hci_stack->le_advertisements_filter_policy = filter_policy;
3460     memcpy(hci_stack->le_advertisements_direct_address, direct_address, 6);
3461 
3462     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3463     gap_advertisments_changed();
3464  }
3465 
3466 /**
3467  * @brief Enable/Disable Advertisements
3468  * @param enabled
3469  */
3470 void gap_advertisements_enable(int enabled){
3471     hci_stack->le_advertisements_enabled = enabled;
3472     if (enabled && !hci_stack->le_advertisements_active){
3473         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
3474     }
3475     if (!enabled && hci_stack->le_advertisements_active){
3476         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
3477     }
3478     hci_run();
3479 }
3480 
3481 
3482 uint8_t gap_disconnect(hci_con_handle_t handle){
3483     hci_connection_t * conn = hci_connection_for_handle(handle);
3484     if (!conn){
3485         hci_emit_disconnection_complete(handle, 0);
3486         return 0;
3487     }
3488     conn->state = SEND_DISCONNECT;
3489     hci_run();
3490     return 0;
3491 }
3492 
3493 /**
3494  * @brief Get connection type
3495  * @param con_handle
3496  * @result connection_type
3497  */
3498 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
3499     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
3500     if (!conn) return GAP_CONNECTION_INVALID;
3501     switch (conn->address_type){
3502         case BD_ADDR_TYPE_LE_PUBLIC:
3503         case BD_ADDR_TYPE_LE_RANDOM:
3504             return GAP_CONNECTION_LE;
3505         case BD_ADDR_TYPE_SCO:
3506             return GAP_CONNECTION_SCO;
3507         case BD_ADDR_TYPE_CLASSIC:
3508             return GAP_CONNECTION_ACL;
3509         default:
3510             return GAP_CONNECTION_INVALID;
3511     }
3512 }
3513 
3514 #ifdef ENABLE_BLE
3515 
3516 /**
3517  * @brief Auto Connection Establishment - Start Connecting to device
3518  * @param address_typ
3519  * @param address
3520  * @returns 0 if ok
3521  */
3522 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
3523     // check capacity
3524     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
3525     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
3526     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
3527     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
3528     entry->address_type = address_type;
3529     memcpy(entry->address, address, 6);
3530     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
3531     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
3532     hci_run();
3533     return 0;
3534 }
3535 
3536 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
3537     btstack_linked_list_iterator_t it;
3538     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3539     while (btstack_linked_list_iterator_has_next(&it)){
3540         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3541         if (entry->address_type != address_type) continue;
3542         if (memcmp(entry->address, address, 6) != 0) continue;
3543         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3544             // remove from controller if already present
3545             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3546             continue;
3547         }
3548         // direclty remove entry from whitelist
3549         btstack_linked_list_iterator_remove(&it);
3550         btstack_memory_whitelist_entry_free(entry);
3551     }
3552 }
3553 
3554 /**
3555  * @brief Auto Connection Establishment - Stop Connecting to device
3556  * @param address_typ
3557  * @param address
3558  * @returns 0 if ok
3559  */
3560 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
3561     hci_remove_from_whitelist(address_type, address);
3562     hci_run();
3563     return 0;
3564 }
3565 
3566 /**
3567  * @brief Auto Connection Establishment - Stop everything
3568  * @note  Convenience function to stop all active auto connection attempts
3569  */
3570 void gap_auto_connection_stop_all(void){
3571     btstack_linked_list_iterator_t it;
3572     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
3573     while (btstack_linked_list_iterator_has_next(&it)){
3574         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
3575         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
3576             // remove from controller if already present
3577             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
3578             continue;
3579         }
3580         // directly remove entry from whitelist
3581         btstack_linked_list_iterator_remove(&it);
3582         btstack_memory_whitelist_entry_free(entry);
3583     }
3584     hci_run();
3585 }
3586 
3587 #endif
3588 
3589 /**
3590  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
3591  */
3592 void hci_set_sco_voice_setting(uint16_t voice_setting){
3593     hci_stack->sco_voice_setting = voice_setting;
3594 }
3595 
3596 /**
3597  * @brief Get SCO Voice Setting
3598  * @return current voice setting
3599  */
3600 uint16_t hci_get_sco_voice_setting(void){
3601     return hci_stack->sco_voice_setting;
3602 }
3603 
3604 /** @brief Get SCO packet length for current SCO Voice setting
3605  *  @note  Using SCO packets of the exact length is required for USB transfer
3606  *  @return Length of SCO packets in bytes (not audio frames)
3607  */
3608 int hci_get_sco_packet_length(void){
3609     // see Core Spec for H2 USB Transfer.
3610     if (hci_stack->sco_voice_setting & 0x0020) return 51;
3611     return 27;
3612 }
3613 
3614 /**
3615  * @brief Set callback for Bluetooth Hardware Error
3616  */
3617 void hci_set_hardware_error_callback(void (*fn)(void)){
3618     hci_stack->hardware_error_callback = fn;
3619 }
3620 
3621 /**
3622  * @brief Set callback for local information from Bluetooth controller right after HCI Reset
3623  * @note Can be used to select chipset driver dynamically during startup
3624  */
3625 void hci_set_local_version_information_callback(void (*fn)(uint8_t * local_version_information)){
3626     hci_stack->local_version_information_callback = fn;
3627 }
3628 
3629 void hci_disconnect_all(void){
3630     btstack_linked_list_iterator_t it;
3631     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
3632     while (btstack_linked_list_iterator_has_next(&it)){
3633         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
3634         if (con->state == SENT_DISCONNECT) continue;
3635         con->state = SEND_DISCONNECT;
3636     }
3637     hci_run();
3638 }
3639