xref: /btstack/src/hci.c (revision 62473419f786e1c73c2750e90453fcdb6d15e98e)
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 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <stdio.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static void hci_notify_if_sco_can_send_now(void);
137 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
138 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
139 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
140 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
141 static void hci_connection_timestamp(hci_connection_t *connection);
142 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
143 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
144 #endif
145 
146 static int  hci_power_control_on(void);
147 static void hci_power_control_off(void);
148 static void hci_state_reset(void);
149 static void hci_emit_transport_packet_sent(void);
150 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
151 static void hci_emit_nr_connections_changed(void);
152 static void hci_emit_hci_open_failed(void);
153 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
154 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
155 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
156 static void hci_run(void);
157 static int  hci_is_le_connection(hci_connection_t * connection);
158 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
159 
160 #ifdef ENABLE_CLASSIC
161 static int hci_have_usb_transport(void);
162 #endif
163 
164 #ifdef ENABLE_BLE
165 #ifdef ENABLE_LE_CENTRAL
166 // called from test/ble_client/advertising_data_parser.c
167 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
168 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
169 static hci_connection_t * gap_get_outgoing_connection(void);
170 #endif
171 #endif
172 
173 // the STACK is here
174 #ifndef HAVE_MALLOC
175 static hci_stack_t   hci_stack_static;
176 #endif
177 static hci_stack_t * hci_stack = NULL;
178 
179 #ifdef ENABLE_CLASSIC
180 // default name
181 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
182 
183 // test helper
184 static uint8_t disable_l2cap_timeouts = 0;
185 #endif
186 
187 /**
188  * create connection for given address
189  *
190  * @return connection OR NULL, if no memory left
191  */
192 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
193     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
194     hci_connection_t * conn = btstack_memory_hci_connection_get();
195     if (!conn) return NULL;
196     bd_addr_copy(conn->address, addr);
197     conn->address_type = addr_type;
198     conn->con_handle = 0xffff;
199     conn->authentication_flags = AUTH_FLAGS_NONE;
200     conn->bonding_flags = 0;
201     conn->requested_security_level = LEVEL_0;
202 #ifdef ENABLE_CLASSIC
203     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
204     btstack_run_loop_set_timer_context(&conn->timeout, conn);
205     hci_connection_timestamp(conn);
206 #endif
207     conn->acl_recombination_length = 0;
208     conn->acl_recombination_pos = 0;
209     conn->num_packets_sent = 0;
210 
211     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
212 #ifdef ENABLE_BLE
213     conn->le_phy_update_all_phys = 0xff;
214 #endif
215     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
216     return conn;
217 }
218 
219 
220 /**
221  * get le connection parameter range
222 *
223  * @return le connection parameter range struct
224  */
225 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
226     *range = hci_stack->le_connection_parameter_range;
227 }
228 
229 /**
230  * set le connection parameter range
231  *
232  */
233 
234 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
235     hci_stack->le_connection_parameter_range = *range;
236 }
237 
238 /**
239  * @brief Test if connection parameters are inside in existing rage
240  * @param conn_interval_min (unit: 1.25ms)
241  * @param conn_interval_max (unit: 1.25ms)
242  * @param conn_latency
243  * @param supervision_timeout (unit: 10ms)
244  * @returns 1 if included
245  */
246 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
247     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
248     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
249 
250     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
251     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
252 
253     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
254     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
255 
256     return 1;
257 }
258 
259 /**
260  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
261  * @note: default: 1
262  * @param max_peripheral_connections
263  */
264 #ifdef ENABLE_LE_PERIPHERAL
265 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
266     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
267 }
268 #endif
269 
270 /**
271  * get hci connections iterator
272  *
273  * @return hci connections iterator
274  */
275 
276 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
277     btstack_linked_list_iterator_init(it, &hci_stack->connections);
278 }
279 
280 /**
281  * get connection for a given handle
282  *
283  * @return connection OR NULL, if not found
284  */
285 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
286     btstack_linked_list_iterator_t it;
287     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
288     while (btstack_linked_list_iterator_has_next(&it)){
289         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
290         if ( item->con_handle == con_handle ) {
291             return item;
292         }
293     }
294     return NULL;
295 }
296 
297 /**
298  * get connection for given address
299  *
300  * @return connection OR NULL, if not found
301  */
302 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
303     btstack_linked_list_iterator_t it;
304     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
305     while (btstack_linked_list_iterator_has_next(&it)){
306         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
307         if (connection->address_type != addr_type)  continue;
308         if (memcmp(addr, connection->address, 6) != 0) continue;
309         return connection;
310     }
311     return NULL;
312 }
313 
314 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
315     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
316 }
317 
318 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
319     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
320 }
321 
322 #ifdef ENABLE_CLASSIC
323 
324 #ifdef ENABLE_SCO_OVER_HCI
325 static int hci_number_sco_connections(void){
326     int connections = 0;
327     btstack_linked_list_iterator_t it;
328     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
329     while (btstack_linked_list_iterator_has_next(&it)){
330         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
331         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
332         connections++;
333     }
334     return connections;
335 }
336 #endif
337 
338 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
339     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
340 #ifdef HAVE_EMBEDDED_TICK
341     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
342         // connections might be timed out
343         hci_emit_l2cap_check_timeout(connection);
344     }
345 #else
346     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
347         // connections might be timed out
348         hci_emit_l2cap_check_timeout(connection);
349     }
350 #endif
351 }
352 
353 static void hci_connection_timestamp(hci_connection_t *connection){
354 #ifdef HAVE_EMBEDDED_TICK
355     connection->timestamp = btstack_run_loop_embedded_get_ticks();
356 #else
357     connection->timestamp = btstack_run_loop_get_time_ms();
358 #endif
359 }
360 
361 /**
362  * add authentication flags and reset timer
363  * @note: assumes classic connection
364  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
365  */
366 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
367     bd_addr_t addr;
368     reverse_bd_addr(bd_addr, addr);
369     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
370     if (conn) {
371         connectionSetAuthenticationFlags(conn, flags);
372         hci_connection_timestamp(conn);
373     }
374 }
375 
376 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
377     hci_connection_t * conn = hci_connection_for_handle(handle);
378     if (!conn) return 0;
379     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
380     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
381     return 0;
382 }
383 
384 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
385     if (!hci_stack->link_key_db) return;
386     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
387     hci_stack->link_key_db->delete_link_key(addr);
388 }
389 
390 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
391     if (!hci_stack->link_key_db) return;
392     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
393     hci_stack->link_key_db->put_link_key(addr, link_key, type);
394 }
395 
396 void gap_delete_all_link_keys(void){
397     bd_addr_t  addr;
398     link_key_t link_key;
399     link_key_type_t type;
400     btstack_link_key_iterator_t it;
401     int ok = gap_link_key_iterator_init(&it);
402     if (!ok) {
403         log_error("could not initialize iterator");
404         return;
405     }
406     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
407         gap_drop_link_key_for_bd_addr(addr);
408     }
409     gap_link_key_iterator_done(&it);
410 }
411 
412 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
413     if (!hci_stack->link_key_db) return 0;
414     if (!hci_stack->link_key_db->iterator_init) return 0;
415     return hci_stack->link_key_db->iterator_init(it);
416 }
417 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
418     if (!hci_stack->link_key_db) return 0;
419     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
420 }
421 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
422     if (!hci_stack->link_key_db) return;
423     hci_stack->link_key_db->iterator_done(it);
424 }
425 #endif
426 
427 static int hci_is_le_connection(hci_connection_t * connection){
428     switch (connection->address_type){
429         case BD_ADDR_TYPE_LE_PUBLIC:
430         case BD_ADDR_TYPE_LE_RANDOM:
431         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
432         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
433             return 1;
434         default:
435             return 0;
436     }
437 }
438 
439 /**
440  * count connections
441  */
442 static int nr_hci_connections(void){
443     int count = 0;
444     btstack_linked_item_t *it;
445     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
446         count++;
447     }
448     return count;
449 }
450 
451 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
452 
453     unsigned int num_packets_sent_classic = 0;
454     unsigned int num_packets_sent_le = 0;
455 
456     btstack_linked_item_t *it;
457     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
458         hci_connection_t * connection = (hci_connection_t *) it;
459         if (hci_is_le_connection(connection)){
460             num_packets_sent_le += connection->num_packets_sent;
461         }
462         if (connection->address_type == BD_ADDR_TYPE_ACL){
463             num_packets_sent_classic += connection->num_packets_sent;
464         }
465     }
466     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
467     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
468     int free_slots_le = 0;
469 
470     if (free_slots_classic < 0){
471         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);
472         return 0;
473     }
474 
475     if (hci_stack->le_acl_packets_total_num){
476         // if we have LE slots, they are used
477         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
478         if (free_slots_le < 0){
479             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);
480             return 0;
481         }
482     } else {
483         // otherwise, classic slots are used for LE, too
484         free_slots_classic -= num_packets_sent_le;
485         if (free_slots_classic < 0){
486             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);
487             return 0;
488         }
489     }
490 
491     switch (address_type){
492         case BD_ADDR_TYPE_UNKNOWN:
493             log_error("hci_number_free_acl_slots: unknown address type");
494             return 0;
495 
496         case BD_ADDR_TYPE_ACL:
497             return free_slots_classic;
498 
499         default:
500            if (hci_stack->le_acl_packets_total_num){
501                return free_slots_le;
502            }
503            return free_slots_classic;
504     }
505 }
506 
507 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
508     // get connection type
509     hci_connection_t * connection = hci_connection_for_handle(con_handle);
510     if (!connection){
511         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
512         return 0;
513     }
514     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
515 }
516 
517 #ifdef ENABLE_CLASSIC
518 static int hci_number_free_sco_slots(void){
519     unsigned int num_sco_packets_sent  = 0;
520     btstack_linked_item_t *it;
521     if (hci_stack->synchronous_flow_control_enabled){
522         // explicit flow control
523         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
524             hci_connection_t * connection = (hci_connection_t *) it;
525             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
526             num_sco_packets_sent += connection->num_packets_sent;
527         }
528         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
529             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
530             return 0;
531         }
532         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
533     } else {
534         // implicit flow control -- TODO
535         int num_ready = 0;
536         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
537             hci_connection_t * connection = (hci_connection_t *) it;
538             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
539             if (connection->sco_tx_ready == 0) continue;
540             num_ready++;
541         }
542         return num_ready;
543     }
544 }
545 #endif
546 
547 // only used to send HCI Host Number Completed Packets
548 static int hci_can_send_comand_packet_transport(void){
549     if (hci_stack->hci_packet_buffer_reserved) return 0;
550 
551     // check for async hci transport implementations
552     if (hci_stack->hci_transport->can_send_packet_now){
553         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
554             return 0;
555         }
556     }
557     return 1;
558 }
559 
560 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
561 int hci_can_send_command_packet_now(void){
562     if (hci_can_send_comand_packet_transport() == 0) return 0;
563     return hci_stack->num_cmd_packets > 0;
564 }
565 
566 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
567     // check for async hci transport implementations
568     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
569     return hci_stack->hci_transport->can_send_packet_now(packet_type);
570 }
571 
572 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
573     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
574     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
575 }
576 
577 int hci_can_send_acl_le_packet_now(void){
578     if (hci_stack->hci_packet_buffer_reserved) return 0;
579     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
580 }
581 
582 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
583     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
584     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
585 }
586 
587 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
588     if (hci_stack->hci_packet_buffer_reserved) return 0;
589     return hci_can_send_prepared_acl_packet_now(con_handle);
590 }
591 
592 #ifdef ENABLE_CLASSIC
593 int hci_can_send_acl_classic_packet_now(void){
594     if (hci_stack->hci_packet_buffer_reserved) return 0;
595     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
596 }
597 
598 int hci_can_send_prepared_sco_packet_now(void){
599     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
600     if (hci_have_usb_transport()){
601         return hci_stack->sco_can_send_now;
602     } else {
603         return hci_number_free_sco_slots() > 0;
604     }
605 }
606 
607 int hci_can_send_sco_packet_now(void){
608     if (hci_stack->hci_packet_buffer_reserved) return 0;
609     return hci_can_send_prepared_sco_packet_now();
610 }
611 
612 void hci_request_sco_can_send_now_event(void){
613     hci_stack->sco_waiting_for_can_send_now = 1;
614     hci_notify_if_sco_can_send_now();
615 }
616 #endif
617 
618 // used for internal checks in l2cap.c
619 int hci_is_packet_buffer_reserved(void){
620     return hci_stack->hci_packet_buffer_reserved;
621 }
622 
623 // reserves outgoing packet buffer. @returns 1 if successful
624 int hci_reserve_packet_buffer(void){
625     if (hci_stack->hci_packet_buffer_reserved) {
626         log_error("hci_reserve_packet_buffer called but buffer already reserved");
627         return 0;
628     }
629     hci_stack->hci_packet_buffer_reserved = 1;
630     return 1;
631 }
632 
633 void hci_release_packet_buffer(void){
634     hci_stack->hci_packet_buffer_reserved = 0;
635 }
636 
637 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
638 static int hci_transport_synchronous(void){
639     return hci_stack->hci_transport->can_send_packet_now == NULL;
640 }
641 
642 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
643 
644     // 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);
645 
646     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
647     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
648     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0)){
649         max_acl_data_packet_length = hci_stack->le_data_packets_length;
650     }
651 
652     // testing: reduce buffer to minimum
653     // max_acl_data_packet_length = 52;
654 
655     log_debug("hci_send_acl_packet_fragments entered");
656 
657     int err;
658     // multiple packets could be send on a synchronous HCI transport
659     while (true){
660 
661         log_debug("hci_send_acl_packet_fragments loop entered");
662 
663         // get current data
664         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
665         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
666         int more_fragments = 0;
667 
668         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
669         if (current_acl_data_packet_length > max_acl_data_packet_length){
670             more_fragments = 1;
671             current_acl_data_packet_length = max_acl_data_packet_length;
672         }
673 
674         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
675         if (acl_header_pos > 0){
676             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
677             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
678             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
679         }
680 
681         // update header len
682         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
683 
684         // count packet
685         connection->num_packets_sent++;
686         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
687 
688         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
689         if (more_fragments){
690             // update start of next fragment to send
691             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
692         } else {
693             // done
694             hci_stack->acl_fragmentation_pos = 0;
695             hci_stack->acl_fragmentation_total_size = 0;
696         }
697 
698         // send packet
699         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
700         const int size = current_acl_data_packet_length + 4;
701         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
702         hci_stack->acl_fragmentation_tx_active = 1;
703         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
704 
705         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
706 
707         // done yet?
708         if (!more_fragments) break;
709 
710         // can send more?
711         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
712     }
713 
714     log_debug("hci_send_acl_packet_fragments loop over");
715 
716     // release buffer now for synchronous transport
717     if (hci_transport_synchronous()){
718         hci_stack->acl_fragmentation_tx_active = 0;
719         hci_release_packet_buffer();
720         hci_emit_transport_packet_sent();
721     }
722 
723     return err;
724 }
725 
726 // pre: caller has reserved the packet buffer
727 int hci_send_acl_packet_buffer(int size){
728 
729     // log_info("hci_send_acl_packet_buffer size %u", size);
730 
731     if (!hci_stack->hci_packet_buffer_reserved) {
732         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
733         return 0;
734     }
735 
736     uint8_t * packet = hci_stack->hci_packet_buffer;
737     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
738 
739     // check for free places on Bluetooth module
740     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
741         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
742         hci_release_packet_buffer();
743         hci_emit_transport_packet_sent();
744         return BTSTACK_ACL_BUFFERS_FULL;
745     }
746 
747     hci_connection_t *connection = hci_connection_for_handle( con_handle);
748     if (!connection) {
749         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
750         hci_release_packet_buffer();
751         hci_emit_transport_packet_sent();
752         return 0;
753     }
754 
755 #ifdef ENABLE_CLASSIC
756     hci_connection_timestamp(connection);
757 #endif
758 
759     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
760 
761     // setup data
762     hci_stack->acl_fragmentation_total_size = size;
763     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
764 
765     return hci_send_acl_packet_fragments(connection);
766 }
767 
768 #ifdef ENABLE_CLASSIC
769 // pre: caller has reserved the packet buffer
770 int hci_send_sco_packet_buffer(int size){
771 
772     // log_info("hci_send_acl_packet_buffer size %u", size);
773 
774     if (!hci_stack->hci_packet_buffer_reserved) {
775         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
776         return 0;
777     }
778 
779     uint8_t * packet = hci_stack->hci_packet_buffer;
780 
781     // skip checks in loopback mode
782     if (!hci_stack->loopback_mode){
783         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
784 
785         // check for free places on Bluetooth module
786         if (!hci_can_send_prepared_sco_packet_now()) {
787             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
788             hci_release_packet_buffer();
789             hci_emit_transport_packet_sent();
790             return BTSTACK_ACL_BUFFERS_FULL;
791         }
792 
793         // track send packet in connection struct
794         hci_connection_t *connection = hci_connection_for_handle( con_handle);
795         if (!connection) {
796             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
797             hci_release_packet_buffer();
798             hci_emit_transport_packet_sent();
799             return 0;
800         }
801 
802         if (hci_have_usb_transport()){
803             // token used
804             hci_stack->sco_can_send_now = 0;
805         } else {
806             if (hci_stack->synchronous_flow_control_enabled){
807                 connection->num_packets_sent++;
808             } else {
809                 connection->sco_tx_ready--;
810             }
811         }
812     }
813 
814     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
815     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
816 
817     if (hci_transport_synchronous()){
818         hci_release_packet_buffer();
819         hci_emit_transport_packet_sent();
820     }
821 
822     return err;
823 }
824 #endif
825 
826 static void acl_handler(uint8_t *packet, int size){
827 
828     // log_info("acl_handler: size %u", size);
829 
830     // get info
831     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
832     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
833     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
834     uint16_t acl_length         = READ_ACL_LENGTH(packet);
835 
836     // ignore non-registered handle
837     if (!conn){
838         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
839         return;
840     }
841 
842     // assert packet is complete
843     if ((acl_length + 4) != size){
844         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
845         return;
846     }
847 
848 #ifdef ENABLE_CLASSIC
849     // update idle timestamp
850     hci_connection_timestamp(conn);
851 #endif
852 
853 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
854     hci_stack->host_completed_packets = 1;
855     conn->num_packets_completed++;
856 #endif
857 
858     // handle different packet types
859     switch (acl_flags & 0x03) {
860 
861         case 0x01: // continuation fragment
862 
863             // sanity checks
864             if (conn->acl_recombination_pos == 0) {
865                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
866                 return;
867             }
868             if ((conn->acl_recombination_pos + acl_length) > (4 + HCI_ACL_BUFFER_SIZE)){
869                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
870                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
871                 conn->acl_recombination_pos = 0;
872                 return;
873             }
874 
875             // append fragment payload (header already stored)
876             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
877                          &packet[4], acl_length);
878             conn->acl_recombination_pos += acl_length;
879 
880             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
881             //        conn->acl_recombination_pos, conn->acl_recombination_length);
882 
883             // forward complete L2CAP packet if complete.
884             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4 + 4)){ // pos already incl. ACL header
885                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
886                 // reset recombination buffer
887                 conn->acl_recombination_length = 0;
888                 conn->acl_recombination_pos = 0;
889             }
890             break;
891 
892         case 0x02: { // first fragment
893 
894             // sanity check
895             if (conn->acl_recombination_pos) {
896                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
897                 conn->acl_recombination_pos = 0;
898             }
899 
900             // peek into L2CAP packet!
901             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
902 
903             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
904 
905             // compare fragment size to L2CAP packet size
906             if (acl_length >= (l2cap_length + 4)){
907                 // forward fragment as L2CAP packet
908                 hci_emit_acl_packet(packet, acl_length + 4);
909             } else {
910 
911                 if (acl_length > HCI_ACL_BUFFER_SIZE){
912                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
913                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
914                     return;
915                 }
916 
917                 // store first fragment and tweak acl length for complete package
918                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
919                              packet, acl_length + 4);
920                 conn->acl_recombination_pos    = acl_length + 4;
921                 conn->acl_recombination_length = l2cap_length;
922                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
923             }
924             break;
925 
926         }
927         default:
928             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
929             return;
930     }
931 
932     // execute main loop
933     hci_run();
934 }
935 
936 static void hci_shutdown_connection(hci_connection_t *conn){
937     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
938 
939 #ifdef ENABLE_CLASSIC
940 #ifdef ENABLE_SCO_OVER_HCI
941     int addr_type = conn->address_type;
942 #endif
943 #endif
944 
945     btstack_run_loop_remove_timer(&conn->timeout);
946 
947     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
948     btstack_memory_hci_connection_free( conn );
949 
950     // now it's gone
951     hci_emit_nr_connections_changed();
952 
953 #ifdef ENABLE_CLASSIC
954 #ifdef ENABLE_SCO_OVER_HCI
955     // update SCO
956     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
957         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
958     }
959 #endif
960 #endif
961 }
962 
963 #ifdef ENABLE_CLASSIC
964 
965 static const uint16_t packet_type_sizes[] = {
966     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
967     HCI_ACL_DH1_SIZE, 0, 0, 0,
968     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
969     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
970 };
971 static const uint8_t  packet_type_feature_requirement_bit[] = {
972      0, // 3 slot packets
973      1, // 5 slot packets
974     25, // EDR 2 mpbs
975     26, // EDR 3 mbps
976     39, // 3 slot EDR packts
977     40, // 5 slot EDR packet
978 };
979 static const uint16_t packet_type_feature_packet_mask[] = {
980     0x0f00, // 3 slot packets
981     0xf000, // 5 slot packets
982     0x1102, // EDR 2 mpbs
983     0x2204, // EDR 3 mbps
984     0x0300, // 3 slot EDR packts
985     0x3000, // 5 slot EDR packet
986 };
987 
988 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
989     // enable packet types based on size
990     uint16_t packet_types = 0;
991     unsigned int i;
992     for (i=0;i<16;i++){
993         if (packet_type_sizes[i] == 0) continue;
994         if (packet_type_sizes[i] <= buffer_size){
995             packet_types |= 1 << i;
996         }
997     }
998     // disable packet types due to missing local supported features
999     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1000         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1001         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1002         if (feature_set) continue;
1003         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1004         packet_types &= ~packet_type_feature_packet_mask[i];
1005     }
1006     // flip bits for "may not be used"
1007     packet_types ^= 0x3306;
1008     return packet_types;
1009 }
1010 
1011 uint16_t hci_usable_acl_packet_types(void){
1012     return hci_stack->packet_types;
1013 }
1014 #endif
1015 
1016 uint8_t* hci_get_outgoing_packet_buffer(void){
1017     // hci packet buffer is >= acl data packet length
1018     return hci_stack->hci_packet_buffer;
1019 }
1020 
1021 uint16_t hci_max_acl_data_packet_length(void){
1022     return hci_stack->acl_data_packet_length;
1023 }
1024 
1025 #ifdef ENABLE_CLASSIC
1026 int hci_extended_sco_link_supported(void){
1027     // No. 31, byte 3, bit 7
1028     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1029 }
1030 #endif
1031 
1032 int hci_non_flushable_packet_boundary_flag_supported(void){
1033     // No. 54, byte 6, bit 6
1034     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1035 }
1036 
1037 static int gap_ssp_supported(void){
1038     // No. 51, byte 6, bit 3
1039     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1040 }
1041 
1042 static int hci_classic_supported(void){
1043 #ifdef ENABLE_CLASSIC
1044     // No. 37, byte 4, bit 5, = No BR/EDR Support
1045     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1046 #else
1047     return 0;
1048 #endif
1049 }
1050 
1051 static int hci_le_supported(void){
1052 #ifdef ENABLE_BLE
1053     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1054     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1055 #else
1056     return 0;
1057 #endif
1058 }
1059 
1060 #ifdef ENABLE_BLE
1061 
1062 /**
1063  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1064  */
1065 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1066     *addr_type = hci_stack->le_own_addr_type;
1067     if (hci_stack->le_own_addr_type){
1068         (void)memcpy(addr, hci_stack->le_random_address, 6);
1069     } else {
1070         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1071     }
1072 }
1073 
1074 #ifdef ENABLE_LE_CENTRAL
1075 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1076 
1077     int offset = 3;
1078     int num_reports = packet[offset];
1079     offset += 1;
1080 
1081     int i;
1082     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1083     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1084     for (i=0; (i<num_reports) && (offset < size);i++){
1085         // sanity checks on data_length:
1086         uint8_t data_length = packet[offset + 8];
1087         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1088         if ((offset + 9 + data_length + 1) > size)    return;
1089         // setup event
1090         uint8_t event_size = 10 + data_length;
1091         int pos = 0;
1092         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1093         event[pos++] = event_size;
1094         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1095         offset += 8;
1096         pos += 8;
1097         event[pos++] = packet[offset + 1 + data_length]; // rssi
1098         event[pos++] = data_length;
1099         offset++;
1100         (void)memcpy(&event[pos], &packet[offset], data_length);
1101         pos +=    data_length;
1102         offset += data_length + 1; // rssi
1103         hci_emit_event(event, pos, 1);
1104     }
1105 }
1106 #endif
1107 #endif
1108 
1109 #ifdef ENABLE_BLE
1110 #ifdef ENABLE_LE_PERIPHERAL
1111 static void hci_reenable_advertisements_if_needed(void){
1112     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1113         // get number of active le slave connections
1114         int num_slave_connections = 0;
1115         btstack_linked_list_iterator_t it;
1116         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1117         while (btstack_linked_list_iterator_has_next(&it)){
1118             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1119             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1120             if (con->state != OPEN) continue;
1121             if (con->role  != HCI_ROLE_SLAVE) continue;
1122             if (!hci_is_le_connection(con)) continue;
1123             num_slave_connections++;
1124         }
1125         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1126         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1127             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1128         }
1129     }
1130 }
1131 #endif
1132 #endif
1133 
1134 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1135 
1136 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1137     if (!hci_stack->config) return 0;
1138     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1139     // Limit baud rate for Broadcom chipsets to 3 mbps
1140     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1141         baud_rate = 3000000;
1142     }
1143     return baud_rate;
1144 }
1145 
1146 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1147     UNUSED(ds);
1148 
1149     switch (hci_stack->substate){
1150         case HCI_INIT_W4_SEND_RESET:
1151             log_info("Resend HCI Reset");
1152             hci_stack->substate = HCI_INIT_SEND_RESET;
1153             hci_stack->num_cmd_packets = 1;
1154             hci_run();
1155             break;
1156         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1157             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1158             if (hci_stack->hci_transport->reset_link){
1159                 hci_stack->hci_transport->reset_link();
1160             }
1161 
1162             /* fall through */
1163 
1164         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1165             log_info("Resend HCI Reset - CSR Warm Boot");
1166             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1167             hci_stack->num_cmd_packets = 1;
1168             hci_run();
1169             break;
1170         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1171             if (hci_stack->hci_transport->set_baudrate){
1172                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1173                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1174                 hci_stack->hci_transport->set_baudrate(baud_rate);
1175             }
1176             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1177             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1178                 if (hci_stack->hci_transport->reset_link){
1179                     log_info("Link Reset");
1180                     hci_stack->hci_transport->reset_link();
1181                 }
1182                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1183                 hci_run();
1184             }
1185             break;
1186         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1187             // otherwise continue
1188             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1189             hci_send_cmd(&hci_read_local_supported_commands);
1190             break;
1191         default:
1192             break;
1193     }
1194 }
1195 #endif
1196 
1197 static void hci_initializing_next_state(void){
1198     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1199 }
1200 
1201 #if defined(ENABLE_CLASSIC) || defined(ENABLE_LE_PERIPHERAL)
1202 static void hci_replace_bd_addr_placeholder(uint8_t * data, uint16_t size){
1203     const int bd_addr_string_len = 17;
1204     int i = 0;
1205     while (i < (size - bd_addr_string_len)){
1206         if (memcmp(&data[i], "00:00:00:00:00:00", bd_addr_string_len)) {
1207             i++;
1208             continue;
1209         }
1210         // set real address
1211         (void)memcpy(&data[i], bd_addr_to_str(hci_stack->local_bd_addr),
1212                      bd_addr_string_len);
1213         i += bd_addr_string_len;
1214     }
1215 }
1216 #endif
1217 
1218 // assumption: hci_can_send_command_packet_now() == true
1219 static void hci_initializing_run(void){
1220     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1221     switch (hci_stack->substate){
1222         case HCI_INIT_SEND_RESET:
1223             hci_state_reset();
1224 
1225 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1226             // prepare reset if command complete not received in 100ms
1227             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1228             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1229             btstack_run_loop_add_timer(&hci_stack->timeout);
1230 #endif
1231             // send command
1232             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1233             hci_send_cmd(&hci_reset);
1234             break;
1235         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1236             hci_send_cmd(&hci_read_local_version_information);
1237             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1238             break;
1239         case HCI_INIT_SEND_READ_LOCAL_NAME:
1240             hci_send_cmd(&hci_read_local_name);
1241             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1242             break;
1243 
1244 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1245         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1246             hci_state_reset();
1247             // prepare reset if command complete not received in 100ms
1248             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1249             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1250             btstack_run_loop_add_timer(&hci_stack->timeout);
1251             // send command
1252             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1253             hci_send_cmd(&hci_reset);
1254             break;
1255         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1256             hci_state_reset();
1257             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1258             hci_send_cmd(&hci_reset);
1259             break;
1260         case HCI_INIT_SEND_BAUD_CHANGE: {
1261             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1262             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1263             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1264             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1265             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1266             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1267             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1268             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1269                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1270                 btstack_run_loop_add_timer(&hci_stack->timeout);
1271             }
1272             break;
1273         }
1274         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1275             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1276             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1277             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1278             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1279             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1280             break;
1281         }
1282         case HCI_INIT_CUSTOM_INIT:
1283             // Custom initialization
1284             if (hci_stack->chipset && hci_stack->chipset->next_command){
1285                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1286                 int send_cmd = 0;
1287                 switch (hci_stack->chipset_result){
1288                     case BTSTACK_CHIPSET_VALID_COMMAND:
1289                         send_cmd = 1;
1290                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1291                         break;
1292                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1293                         send_cmd = 1;
1294                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1295                         log_info("CSR Warm Boot");
1296                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1297                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1298                         btstack_run_loop_add_timer(&hci_stack->timeout);
1299                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1300                             && hci_stack->config
1301                             && hci_stack->chipset
1302                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1303                             && hci_stack->hci_transport->set_baudrate
1304                             && hci_transport_uart_get_main_baud_rate()){
1305                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1306                         } else {
1307                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1308                         }
1309                         break;
1310                     default:
1311                         break;
1312                 }
1313 
1314                 if (send_cmd){
1315                     int size = 3 + hci_stack->hci_packet_buffer[2];
1316                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1317                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1318                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1319                     break;
1320                 }
1321                 log_info("Init script done");
1322 
1323                 // Init script download on Broadcom chipsets causes:
1324                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1325                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1326                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1327 
1328                     // - baud rate to reset, restore UART baud rate if needed
1329                     int need_baud_change = hci_stack->config
1330                         && hci_stack->chipset
1331                         && hci_stack->chipset->set_baudrate_command
1332                         && hci_stack->hci_transport->set_baudrate
1333                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1334                     if (need_baud_change) {
1335                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1336                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1337                         hci_stack->hci_transport->set_baudrate(baud_rate);
1338                     }
1339 
1340                     uint16_t bcm_delay_ms = 300;
1341                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1342                     //   -> Work around: wait here.
1343                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1344                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1345                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1346                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1347                     btstack_run_loop_add_timer(&hci_stack->timeout);
1348                     break;
1349                 }
1350             }
1351             // otherwise continue
1352             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1353             hci_send_cmd(&hci_read_local_supported_commands);
1354             break;
1355         case HCI_INIT_SET_BD_ADDR:
1356             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1357             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1358             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1359             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1360             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1361             break;
1362 #endif
1363 
1364         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1365             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1366             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1367             hci_send_cmd(&hci_read_local_supported_commands);
1368             break;
1369         case HCI_INIT_READ_BD_ADDR:
1370             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1371             hci_send_cmd(&hci_read_bd_addr);
1372             break;
1373         case HCI_INIT_READ_BUFFER_SIZE:
1374             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1375             hci_send_cmd(&hci_read_buffer_size);
1376             break;
1377         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1378             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1379             hci_send_cmd(&hci_read_local_supported_features);
1380             break;
1381 
1382 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1383         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1384             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1385             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1386             break;
1387         case HCI_INIT_HOST_BUFFER_SIZE:
1388             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1389             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1390                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1391             break;
1392 #endif
1393 
1394         case HCI_INIT_SET_EVENT_MASK:
1395             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1396             if (hci_le_supported()){
1397                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1398             } else {
1399                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1400                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1401             }
1402             break;
1403 
1404 #ifdef ENABLE_CLASSIC
1405         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1407             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1408             break;
1409         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1410             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1411             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1412             break;
1413         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1414             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1415             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1416             break;
1417         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1418             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1419             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1420             break;
1421         case HCI_INIT_WRITE_LOCAL_NAME: {
1422             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1423             hci_reserve_packet_buffer();
1424             uint8_t * packet = hci_stack->hci_packet_buffer;
1425             // construct HCI Command and send
1426             uint16_t opcode = hci_write_local_name.opcode;
1427             hci_stack->last_cmd_opcode = opcode;
1428             packet[0] = opcode & 0xff;
1429             packet[1] = opcode >> 8;
1430             packet[2] = DEVICE_NAME_LEN;
1431             memset(&packet[3], 0, DEVICE_NAME_LEN);
1432             (void)memcpy(&packet[3], hci_stack->local_name,
1433                          strlen(hci_stack->local_name));
1434             // expand '00:00:00:00:00:00' in name with bd_addr
1435             hci_replace_bd_addr_placeholder(&packet[3], DEVICE_NAME_LEN);
1436             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1437             break;
1438         }
1439         case HCI_INIT_WRITE_EIR_DATA: {
1440             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1441             hci_reserve_packet_buffer();
1442             uint8_t * packet = hci_stack->hci_packet_buffer;
1443             // construct HCI Command and send
1444             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1445             hci_stack->last_cmd_opcode = opcode;
1446             packet[0] = opcode & 0xff;
1447             packet[1] = opcode >> 8;
1448             packet[2] = 1 + 240;
1449             packet[3] = 0;  // FEC not required
1450             if (hci_stack->eir_data){
1451                 (void)memcpy(&packet[4], hci_stack->eir_data, 240);
1452             } else {
1453                 memset(&packet[4], 0, 240);
1454                 int name_len = strlen(hci_stack->local_name);
1455                 packet[4] = name_len + 1;
1456                 packet[5] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1457                 (void)memcpy(&packet[6], hci_stack->local_name, name_len);
1458             }
1459             // expand '00:00:00:00:00:00' in name with bd_addr
1460             hci_replace_bd_addr_placeholder(&packet[4], 240);
1461             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + 240);
1462             break;
1463         }
1464         case HCI_INIT_WRITE_INQUIRY_MODE:
1465             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1466             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1467             break;
1468         case HCI_INIT_WRITE_SCAN_ENABLE:
1469             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1470             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1471             break;
1472         // only sent if ENABLE_SCO_OVER_HCI is defined
1473         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1474             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1475             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1476             break;
1477         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1478             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1479             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1480             break;
1481         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1482         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1483             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1484             log_info("BCM: Route SCO data via HCI transport");
1485             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1486             break;
1487 
1488 #endif
1489 #ifdef ENABLE_BLE
1490         // LE INIT
1491         case HCI_INIT_LE_READ_BUFFER_SIZE:
1492             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1493             hci_send_cmd(&hci_le_read_buffer_size);
1494             break;
1495         case HCI_INIT_LE_SET_EVENT_MASK:
1496             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1497             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1498             break;
1499         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1500             // LE Supported Host = 1, Simultaneous Host = 0
1501             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1502             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1503             break;
1504 #endif
1505 
1506 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1507         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1508             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1509             hci_send_cmd(&hci_le_read_maximum_data_length);
1510             break;
1511         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1512             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1513             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1514             break;
1515 #endif
1516 
1517 #ifdef ENABLE_LE_CENTRAL
1518         case HCI_INIT_READ_WHITE_LIST_SIZE:
1519             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1520             hci_send_cmd(&hci_le_read_white_list_size);
1521             break;
1522         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1523             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1524             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1525             hci_send_cmd(&hci_le_set_scan_parameters, 1, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
1526             break;
1527 #endif
1528         default:
1529             return;
1530     }
1531 }
1532 
1533 static void hci_init_done(void){
1534     // done. tell the app
1535     log_info("hci_init_done -> HCI_STATE_WORKING");
1536     hci_stack->state = HCI_STATE_WORKING;
1537     hci_emit_state();
1538     hci_run();
1539 }
1540 
1541 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1542     bool command_completed = false;
1543     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1544         uint16_t opcode = little_endian_read_16(packet,3);
1545         if (opcode == hci_stack->last_cmd_opcode){
1546             command_completed = true;
1547             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1548         } else {
1549             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1550         }
1551     }
1552 
1553     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1554         uint8_t  status = packet[2];
1555         uint16_t opcode = little_endian_read_16(packet,4);
1556         if (opcode == hci_stack->last_cmd_opcode){
1557             if (status){
1558                 command_completed = true;
1559                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1560             } else {
1561                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1562             }
1563         } else {
1564             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1565         }
1566     }
1567 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1568     // Vendor == CSR
1569     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1570         // TODO: track actual command
1571         command_completed = true;
1572     }
1573 
1574     // Vendor == Toshiba
1575     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1576         // TODO: track actual command
1577         command_completed = true;
1578         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1579         hci_stack->num_cmd_packets = 1;
1580     }
1581 #endif
1582 
1583     return command_completed;
1584 }
1585 
1586 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1587 
1588     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1589 
1590     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1591 
1592 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1593 
1594     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1595     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1596     //
1597     // HCI Reset
1598     // Timeout 100 ms
1599     // HCI Reset
1600     // Command Complete Reset
1601     // HCI Read Local Version Information
1602     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1603     // hang...
1604     //
1605     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1606     if (!command_completed
1607             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1608             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1609 
1610         uint16_t opcode = little_endian_read_16(packet,3);
1611         if (opcode == hci_reset.opcode){
1612             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1613             return;
1614         }
1615     }
1616 
1617     // CSR & H5
1618     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1619     if (!command_completed
1620             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1621             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1622 
1623         uint16_t opcode = little_endian_read_16(packet,3);
1624         if (opcode == hci_reset.opcode){
1625             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1626             return;
1627         }
1628     }
1629 
1630     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1631     // fix: Correct substate and behave as command below
1632     if (command_completed){
1633         switch (hci_stack->substate){
1634             case HCI_INIT_SEND_RESET:
1635                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1636                 break;
1637             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1638                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1639                 break;
1640             default:
1641                 break;
1642         }
1643     }
1644 
1645 #endif
1646 
1647     if (!command_completed) return;
1648 
1649     bool need_baud_change = false;
1650     bool need_addr_change = false;
1651 
1652 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1653     need_baud_change = hci_stack->config
1654                         && hci_stack->chipset
1655                         && hci_stack->chipset->set_baudrate_command
1656                         && hci_stack->hci_transport->set_baudrate
1657                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1658 
1659     need_addr_change = hci_stack->custom_bd_addr_set
1660                         && hci_stack->chipset
1661                         && hci_stack->chipset->set_bd_addr_command;
1662 #endif
1663 
1664     switch(hci_stack->substate){
1665 
1666 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1667         case HCI_INIT_SEND_RESET:
1668             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1669             // fix: just correct substate and behave as command below
1670             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1671             btstack_run_loop_remove_timer(&hci_stack->timeout);
1672             break;
1673         case HCI_INIT_W4_SEND_RESET:
1674             btstack_run_loop_remove_timer(&hci_stack->timeout);
1675             break;
1676         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1677             log_info("Received local name, need baud change %d", (int) need_baud_change);
1678             if (need_baud_change){
1679                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1680                 return;
1681             }
1682             // skip baud change
1683             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1684             return;
1685         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1686             // for STLC2500D, baud rate change already happened.
1687             // for others, baud rate gets changed now
1688             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1689                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1690                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1691                 hci_stack->hci_transport->set_baudrate(baud_rate);
1692             }
1693             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1694             return;
1695         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1696             btstack_run_loop_remove_timer(&hci_stack->timeout);
1697             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1698             return;
1699         case HCI_INIT_W4_CUSTOM_INIT:
1700             // repeat custom init
1701             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1702             return;
1703 #else
1704         case HCI_INIT_W4_SEND_RESET:
1705             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1706             return ;
1707 #endif
1708 
1709         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1710             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1711               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1712                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1713                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1714                 return;
1715             }
1716             if (need_addr_change){
1717                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1718                 return;
1719             }
1720             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1721             return;
1722 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1723         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1724             if (need_baud_change){
1725                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1726                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1727                 hci_stack->hci_transport->set_baudrate(baud_rate);
1728             }
1729             if (need_addr_change){
1730                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1731                 return;
1732             }
1733             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1734             return;
1735         case HCI_INIT_W4_SET_BD_ADDR:
1736             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1737             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1738             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1739                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1740                 return;
1741             }
1742             // skipping st warm boot
1743             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1744             return;
1745         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1746             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1747             return;
1748 #endif
1749         case HCI_INIT_W4_READ_BD_ADDR:
1750             // only read buffer size if supported
1751             if (hci_stack->local_supported_commands[0] & 0x01) {
1752                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1753                 return;
1754             }
1755             // skipping read buffer size
1756             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1757             return;
1758         case HCI_INIT_W4_SET_EVENT_MASK:
1759             // skip Classic init commands for LE only chipsets
1760             if (!hci_classic_supported()){
1761 #ifdef ENABLE_BLE
1762                 if (hci_le_supported()){
1763                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1764                     return;
1765                 }
1766 #endif
1767                 log_error("Neither BR/EDR nor LE supported");
1768                 hci_init_done();
1769                 return;
1770             }
1771             if (!gap_ssp_supported()){
1772                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1773                 return;
1774             }
1775             break;
1776 #ifdef ENABLE_BLE
1777         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1778             // skip write le host if not supported (e.g. on LE only EM9301)
1779             if (hci_stack->local_supported_commands[0] & 0x02) break;
1780             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1781             return;
1782 
1783 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1784         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1785             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1786             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1787                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1788                 return;
1789             }
1790             // explicit fall through to reduce repetitions
1791 
1792 #ifdef ENABLE_LE_CENTRAL
1793             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1794 #else
1795             hci_init_done();
1796 #endif
1797             return;
1798 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1799 
1800 #endif  /* ENABLE_BLE */
1801 
1802 #ifdef ENABLE_SCO_OVER_HCI
1803         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1804             // skip write synchronous flow control if not supported
1805             if (hci_stack->local_supported_commands[0] & 0x04) break;
1806             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1807 
1808             /* fall through */
1809 
1810         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1811             // skip write default erroneous data reporting if not supported
1812             if (hci_stack->local_supported_commands[0] & 0x08) break;
1813             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1814 
1815             /* fall through */
1816 
1817         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1818             // skip bcm set sco pcm config on non-Broadcom chipsets
1819             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1820             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1821 
1822             /* fall through */
1823 
1824         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1825             if (!hci_le_supported()){
1826                 // SKIP LE init for Classic only configuration
1827                 hci_init_done();
1828                 return;
1829             }
1830             break;
1831 
1832 #else /* !ENABLE_SCO_OVER_HCI */
1833 
1834         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1835 #ifdef ENABLE_BLE
1836             if (hci_le_supported()){
1837                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1838                 return;
1839             }
1840 #endif
1841             // SKIP LE init for Classic only configuration
1842             hci_init_done();
1843             return;
1844 #endif /* ENABLE_SCO_OVER_HCI */
1845 
1846 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1847 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1848         // Response to command before init done state -> init done
1849         case (HCI_INIT_DONE-1):
1850             hci_init_done();
1851             return;
1852 #endif
1853 
1854         default:
1855             break;
1856     }
1857     hci_initializing_next_state();
1858 }
1859 
1860 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1861     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1862     bd_addr_t bd_address;
1863     (void)memcpy(&bd_address, conn->address, 6);
1864 
1865 #ifdef ENABLE_CLASSIC
1866     // cache needed data
1867     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1868 #endif
1869 
1870     // connection failed, remove entry
1871     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1872     btstack_memory_hci_connection_free( conn );
1873 
1874 #ifdef ENABLE_CLASSIC
1875     // notify client if dedicated bonding
1876     if (notify_dedicated_bonding_failed){
1877         log_info("hci notify_dedicated_bonding_failed");
1878         hci_emit_dedicated_bonding_result(bd_address, status);
1879     }
1880 
1881     // if authentication error, also delete link key
1882     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1883         gap_drop_link_key_for_bd_addr(bd_address);
1884     }
1885 #endif
1886 }
1887 
1888 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1889     // handle BT initialization
1890     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1891         hci_initializing_event_handler(packet, size);
1892     }
1893 
1894     // help with BT sleep
1895     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1896         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1897         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1898         hci_initializing_next_state();
1899     }
1900 }
1901 
1902 static void event_handler(uint8_t *packet, int size){
1903 
1904     uint16_t event_length = packet[1];
1905 
1906     // assert packet is complete
1907     if (size != (event_length + 2)){
1908         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1909         return;
1910     }
1911 
1912     bd_addr_t addr;
1913     bd_addr_type_t addr_type;
1914     hci_con_handle_t handle;
1915     hci_connection_t * conn;
1916     int i;
1917     int create_connection_cmd;
1918 
1919 #ifdef ENABLE_CLASSIC
1920     uint8_t link_type;
1921 #endif
1922 
1923     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1924 
1925     switch (hci_event_packet_get_type(packet)) {
1926 
1927         case HCI_EVENT_COMMAND_COMPLETE:
1928             // get num cmd packets - limit to 1 to reduce complexity
1929             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1930 
1931             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1932                 if (packet[5]) break;
1933                 // terminate, name 248 chars
1934                 packet[6+248] = 0;
1935                 log_info("local name: %s", &packet[6]);
1936             }
1937             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1938                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1939                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1940                     uint16_t acl_len = little_endian_read_16(packet, 6);
1941                     uint16_t sco_len = packet[8];
1942 
1943                     // determine usable ACL/SCO payload size
1944                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1945                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1946 
1947                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1948                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1949 
1950                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1951                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1952                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1953                 }
1954             }
1955             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
1956                 if (packet[5] == 0){
1957                     uint8_t event[5];
1958                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
1959                     event[1] = 3;
1960                     (void)memcpy(&event[2], &packet[6], 3);
1961                     hci_emit_event(event, sizeof(event), 1);
1962                 }
1963             }
1964 #ifdef ENABLE_BLE
1965             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1966                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1967                 hci_stack->le_acl_packets_total_num  = packet[8];
1968                 // determine usable ACL payload size
1969                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1970                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1971                 }
1972                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1973             }
1974 #endif
1975 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1976             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
1977                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
1978                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
1979                 log_info("hci_le_read_maximum_data_length: tx octets %u, tx time %u us", hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1980             }
1981 #endif
1982 #ifdef ENABLE_LE_CENTRAL
1983             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
1984                 hci_stack->le_whitelist_capacity = packet[6];
1985                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
1986             }
1987 #endif
1988             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
1989                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
1990 				hci_stack->local_bd_addr);
1991                 log_info("Local Address, Status: 0x%02x: Addr: %s",
1992                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
1993 #ifdef ENABLE_CLASSIC
1994                 if (hci_stack->link_key_db){
1995                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
1996                 }
1997 #endif
1998             }
1999 #ifdef ENABLE_CLASSIC
2000             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2001                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2002             }
2003             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2004                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2005                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2006                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2007                     hci_emit_event(event, sizeof(event), 1);
2008                 }
2009             }
2010 #endif
2011 
2012             // Note: HCI init checks
2013             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2014                 (void)memcpy(hci_stack->local_supported_features,
2015 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2016 			     8);
2017 
2018 #ifdef ENABLE_CLASSIC
2019                 // determine usable ACL packet types based on host buffer size and supported features
2020                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2021                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2022 #endif
2023                 // Classic/LE
2024                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2025             }
2026             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2027                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2028                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2029                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2030                 // map Cypress to Broadcom
2031                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2032                     log_info("Treat Cypress as Broadcom");
2033                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2034                     little_endian_store_16(packet, 10, manufacturer);
2035                 }
2036                 hci_stack->manufacturer = manufacturer;
2037                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2038                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2039                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2040             }
2041             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2042                 hci_stack->local_supported_commands[0] =
2043                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2044                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2045                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2046                      (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)       |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2047                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2048                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2049                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2050                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2051                     log_info("Local supported commands summary 0x%02x", hci_stack->local_supported_commands[0]);
2052             }
2053 #ifdef ENABLE_CLASSIC
2054             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2055                 if (packet[5] == 0){
2056                     hci_stack->synchronous_flow_control_enabled = 1;
2057                 }
2058             }
2059             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2060                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2061                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2062                 conn   = hci_connection_for_handle(handle);
2063                 if (!conn) break;
2064                 if (status == 0){
2065                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2066                     log_info("Handle %x04x key Size: %u", handle, key_size);
2067                     conn->encryption_key_size = key_size;
2068                 } else {
2069                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2070                     conn->encryption_key_size = 1;
2071                 }
2072                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2073                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2074             }
2075 #endif
2076             break;
2077 
2078         case HCI_EVENT_COMMAND_STATUS:
2079             // get num cmd packets - limit to 1 to reduce complexity
2080             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2081 
2082             // check command status to detected failed outgoing connections
2083             create_connection_cmd = 0;
2084 #ifdef ENABLE_CLASSIC
2085             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2086                 create_connection_cmd = 1;
2087             }
2088 #endif
2089 #ifdef ENABLE_LE_CENTRAL
2090             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2091                 create_connection_cmd = 1;
2092             }
2093 #endif
2094             if (create_connection_cmd) {
2095                 uint8_t status = hci_event_command_status_get_status(packet);
2096                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2097                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), hci_stack->outgoing_addr_type);
2098 
2099                 // reset outgoing address info
2100                 memset(hci_stack->outgoing_addr, 0, 6);
2101                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2102 
2103                 // error => outgoing connection failed
2104                 if ((conn != NULL) && (status != 0)){
2105                     hci_handle_connection_failed(conn, status);
2106                 }
2107             }
2108             break;
2109 
2110         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2111             if (size < 3) return;
2112             uint16_t num_handles = packet[2];
2113             if (size != (3 + num_handles * 4)) return;
2114             uint16_t offset = 3;
2115             for (i=0; i<num_handles;i++){
2116                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2117                 offset += 2;
2118                 uint16_t num_packets = little_endian_read_16(packet, offset);
2119                 offset += 2;
2120 
2121                 conn = hci_connection_for_handle(handle);
2122                 if (!conn){
2123                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2124                     continue;
2125                 }
2126 
2127                 if (conn->num_packets_sent >= num_packets){
2128                     conn->num_packets_sent -= num_packets;
2129                 } else {
2130                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2131                     conn->num_packets_sent = 0;
2132                 }
2133                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2134 
2135 #ifdef ENABLE_CLASSIC
2136                 // For SCO, we do the can_send_now_check here
2137                 hci_notify_if_sco_can_send_now();
2138 #endif
2139             }
2140             break;
2141         }
2142 
2143 #ifdef ENABLE_CLASSIC
2144         case HCI_EVENT_INQUIRY_COMPLETE:
2145             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2146                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2147                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2148                 hci_emit_event(event, sizeof(event), 1);
2149             }
2150             break;
2151         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2152             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2153                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2154             }
2155             break;
2156         case HCI_EVENT_CONNECTION_REQUEST:
2157             reverse_bd_addr(&packet[2], addr);
2158             if (hci_stack->gap_classic_accept_callback != NULL){
2159                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2160                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2161                     bd_addr_copy(hci_stack->decline_addr, addr);
2162                     break;
2163                 }
2164             }
2165 
2166             // TODO: eval COD 8-10
2167             link_type = packet[11];
2168             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2169             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2170             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2171             if (!conn) {
2172                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2173             }
2174             if (!conn) {
2175                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2176                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2177                 bd_addr_copy(hci_stack->decline_addr, addr);
2178                 break;
2179             }
2180             conn->role  = HCI_ROLE_SLAVE;
2181             conn->state = RECEIVED_CONNECTION_REQUEST;
2182             // store info about eSCO
2183             if (link_type == 0x02){
2184                 conn->remote_supported_feature_eSCO = 1;
2185             }
2186             hci_run();
2187             break;
2188 
2189         case HCI_EVENT_CONNECTION_COMPLETE:
2190             // Connection management
2191             reverse_bd_addr(&packet[5], addr);
2192             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2193             addr_type = BD_ADDR_TYPE_ACL;
2194             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2195             if (conn) {
2196                 if (!packet[2]){
2197                     conn->state = OPEN;
2198                     conn->con_handle = little_endian_read_16(packet, 3);
2199 
2200                     // queue get remote feature
2201                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
2202 
2203                     // queue set supervision timeout if we're master
2204                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2205                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2206                     }
2207 
2208                     // restart timer
2209                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2210                     btstack_run_loop_add_timer(&conn->timeout);
2211 
2212                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2213 
2214                     hci_emit_nr_connections_changed();
2215                 } else {
2216                     // connection failed
2217                     hci_handle_connection_failed(conn, packet[2]);
2218                 }
2219             }
2220             break;
2221 
2222         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2223             reverse_bd_addr(&packet[5], addr);
2224             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2225             if (packet[2]){
2226                 // connection failed
2227                 break;
2228             }
2229             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2230             if (!conn) {
2231                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2232             }
2233             if (!conn) {
2234                 break;
2235             }
2236             conn->state = OPEN;
2237             conn->con_handle = little_endian_read_16(packet, 3);
2238 
2239 #ifdef ENABLE_SCO_OVER_HCI
2240             // update SCO
2241             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2242                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2243             }
2244             // trigger can send now
2245             if (hci_have_usb_transport()){
2246                 hci_stack->sco_can_send_now = 1;
2247             }
2248 #endif
2249             break;
2250 
2251         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2252             handle = little_endian_read_16(packet, 3);
2253             conn = hci_connection_for_handle(handle);
2254             if (!conn) break;
2255             if (!packet[2]){
2256                 uint8_t * features = &packet[5];
2257                 if (features[6] & (1 << 3)){
2258                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
2259                 }
2260                 if (features[3] & (1<<7)){
2261                     conn->remote_supported_feature_eSCO = 1;
2262                 }
2263             }
2264             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2265             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
2266             if (conn->bonding_flags & BONDING_DEDICATED){
2267                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2268             }
2269             break;
2270 
2271         case HCI_EVENT_LINK_KEY_REQUEST:
2272             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2273             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2274             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2275             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2276             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2277             hci_run();
2278             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2279             return;
2280 
2281         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2282             reverse_bd_addr(&packet[2], addr);
2283             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2284             if (!conn) break;
2285             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2286             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2287             // Change Connection Encryption keeps link key type
2288             if (link_key_type != CHANGED_COMBINATION_KEY){
2289                 conn->link_key_type = link_key_type;
2290             }
2291             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2292             // still forward event to allow dismiss of pairing dialog
2293             break;
2294         }
2295 
2296         case HCI_EVENT_PIN_CODE_REQUEST:
2297             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2298             // non-bondable mode: pin code negative reply will be sent
2299             if (!hci_stack->bondable){
2300                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2301                 hci_run();
2302                 return;
2303             }
2304             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2305             if (!hci_stack->link_key_db) break;
2306             hci_event_pin_code_request_get_bd_addr(packet, addr);
2307             hci_stack->link_key_db->delete_link_key(addr);
2308             break;
2309 
2310         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2311             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2312             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2313             break;
2314 
2315         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2316             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2317             if (!hci_stack->ssp_auto_accept) break;
2318             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2319             break;
2320 
2321         case HCI_EVENT_USER_PASSKEY_REQUEST:
2322             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2323             if (!hci_stack->ssp_auto_accept) break;
2324             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2325             break;
2326         case HCI_EVENT_MODE_CHANGE:
2327             handle = hci_event_mode_change_get_handle(packet);
2328             conn = hci_connection_for_handle(handle);
2329             if (!conn) break;
2330             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2331             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2332             break;
2333 #endif
2334 
2335         case HCI_EVENT_ENCRYPTION_CHANGE:
2336             handle = little_endian_read_16(packet, 3);
2337             conn = hci_connection_for_handle(handle);
2338             if (!conn) break;
2339             if (packet[2] == 0) {
2340                 if (packet[5]){
2341                     if (hci_is_le_connection(conn)){
2342                         // For LE, we accept connection as encrypted
2343                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2344                     }
2345 #ifdef ENABLE_CLASSIC
2346                     else {
2347                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2348                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2349                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2350                         } else {
2351                             // if not, pretend everything is perfect
2352                             conn->encryption_key_size = 16;
2353                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2354                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2355                         }
2356                     }
2357 #endif
2358                 } else {
2359                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2360                 }
2361             }
2362 
2363             break;
2364 
2365 #ifdef ENABLE_CLASSIC
2366         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2367             handle = little_endian_read_16(packet, 3);
2368             conn = hci_connection_for_handle(handle);
2369             if (!conn) break;
2370 
2371             // dedicated bonding: send result and disconnect
2372             if (conn->bonding_flags & BONDING_DEDICATED){
2373                 conn->bonding_flags &= ~BONDING_DEDICATED;
2374                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2375                 conn->bonding_status = packet[2];
2376                 break;
2377             }
2378 
2379             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2380                 // link key sufficient for requested security
2381                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2382                 break;
2383             }
2384             // not enough
2385             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2386             break;
2387 #endif
2388 
2389         // HCI_EVENT_DISCONNECTION_COMPLETE
2390         // has been split, to first notify stack before shutting connection down
2391         // see end of function, too.
2392         case HCI_EVENT_DISCONNECTION_COMPLETE:
2393             if (packet[2]) break;   // status != 0
2394             handle = little_endian_read_16(packet, 3);
2395             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2396             if (hci_stack->acl_fragmentation_total_size > 0) {
2397                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2398                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2399                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2400                     hci_stack->acl_fragmentation_total_size = 0;
2401                     hci_stack->acl_fragmentation_pos = 0;
2402                     if (release_buffer){
2403                         hci_release_packet_buffer();
2404                     }
2405                 }
2406             }
2407 
2408             // re-enable advertisements for le connections if active
2409             conn = hci_connection_for_handle(handle);
2410             if (!conn) break;
2411             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2412 #ifdef ENABLE_BLE
2413 #ifdef ENABLE_LE_PERIPHERAL
2414             if (hci_is_le_connection(conn)){
2415                 hci_reenable_advertisements_if_needed();
2416             }
2417 #endif
2418 #endif
2419             break;
2420 
2421         case HCI_EVENT_HARDWARE_ERROR:
2422             log_error("Hardware Error: 0x%02x", packet[2]);
2423             if (hci_stack->hardware_error_callback){
2424                 (*hci_stack->hardware_error_callback)(packet[2]);
2425             } else {
2426                 // if no special requests, just reboot stack
2427                 hci_power_control_off();
2428                 hci_power_control_on();
2429             }
2430             break;
2431 
2432 #ifdef ENABLE_CLASSIC
2433         case HCI_EVENT_ROLE_CHANGE:
2434             if (packet[2]) break;   // status != 0
2435             reverse_bd_addr(&packet[3], addr);
2436             addr_type = BD_ADDR_TYPE_ACL;
2437             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2438             if (!conn) break;
2439             conn->role = packet[9];
2440             break;
2441 #endif
2442 
2443         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2444             // release packet buffer only for asynchronous transport and if there are not further fragements
2445             if (hci_transport_synchronous()) {
2446                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2447                 return; // instead of break: to avoid re-entering hci_run()
2448             }
2449             hci_stack->acl_fragmentation_tx_active = 0;
2450             if (hci_stack->acl_fragmentation_total_size) break;
2451             hci_release_packet_buffer();
2452 
2453             // L2CAP receives this event via the hci_emit_event below
2454 
2455 #ifdef ENABLE_CLASSIC
2456             // For SCO, we do the can_send_now_check here
2457             hci_notify_if_sco_can_send_now();
2458 #endif
2459             break;
2460 
2461 #ifdef ENABLE_CLASSIC
2462         case HCI_EVENT_SCO_CAN_SEND_NOW:
2463             // For SCO, we do the can_send_now_check here
2464             hci_stack->sco_can_send_now = 1;
2465             hci_notify_if_sco_can_send_now();
2466             return;
2467 
2468         // explode inquriy results for easier consumption
2469         case HCI_EVENT_INQUIRY_RESULT:
2470         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2471         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2472             gap_inquiry_explode(packet, size);
2473             break;
2474 #endif
2475 
2476 #ifdef ENABLE_BLE
2477         case HCI_EVENT_LE_META:
2478             switch (packet[2]){
2479 #ifdef ENABLE_LE_CENTRAL
2480                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2481                     // log_info("advertising report received");
2482                     if (!hci_stack->le_scanning_enabled) break;
2483                     le_handle_advertisement_report(packet, size);
2484                     break;
2485 #endif
2486                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2487                     // Connection management
2488                     reverse_bd_addr(&packet[8], addr);
2489                     addr_type = (bd_addr_type_t)packet[7];
2490                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2491                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2492 
2493 #ifdef ENABLE_LE_CENTRAL
2494                     // if auto-connect, remove from whitelist in both roles
2495                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2496                         hci_remove_from_whitelist(addr_type, addr);
2497                     }
2498                     // handle error: error is reported only to the initiator -> outgoing connection
2499                     if (packet[3]){
2500 
2501                         // handle cancelled outgoing connection
2502                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2503                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2504                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2505                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2506                             conn = gap_get_outgoing_connection();
2507                         }
2508 
2509                         // outgoing connection establishment is done
2510                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2511                         // remove entry
2512                         if (conn){
2513                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2514                             btstack_memory_hci_connection_free( conn );
2515                         }
2516                         break;
2517                     }
2518 #endif
2519                     // on success, both hosts receive connection complete event
2520                     if (packet[6] == HCI_ROLE_MASTER){
2521 #ifdef ENABLE_LE_CENTRAL
2522                         // if we're master, it was an outgoing connection and we're done with it
2523                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2524 #endif
2525                     } else {
2526 #ifdef ENABLE_LE_PERIPHERAL
2527                         // if we're slave, it was an incoming connection, advertisements have stopped
2528                         hci_stack->le_advertisements_active = 0;
2529 #endif
2530                     }
2531                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2532                     if (!conn){
2533                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2534                     }
2535                     // no memory, sorry.
2536                     if (!conn){
2537                         break;
2538                     }
2539 
2540                     conn->state = OPEN;
2541                     conn->role  = packet[6];
2542                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2543                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2544 
2545 #ifdef ENABLE_LE_PERIPHERAL
2546                     if (packet[6] == HCI_ROLE_SLAVE){
2547                         hci_reenable_advertisements_if_needed();
2548                     }
2549 #endif
2550 
2551                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2552 
2553                     // restart timer
2554                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2555                     // btstack_run_loop_add_timer(&conn->timeout);
2556 
2557                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2558 
2559                     hci_emit_nr_connections_changed();
2560                     break;
2561 
2562                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2563                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2564                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2565                     conn = hci_connection_for_handle(handle);
2566                     if (!conn) break;
2567                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2568                     break;
2569 
2570                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2571                     // connection
2572                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2573                     conn = hci_connection_for_handle(handle);
2574                     if (conn) {
2575                         // read arguments
2576                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2577                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2578                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2579                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2580 
2581                         // validate against current connection parameter range
2582                         le_connection_parameter_range_t existing_range;
2583                         gap_get_connection_parameter_range(&existing_range);
2584                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2585                         if (update_parameter){
2586                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2587                             conn->le_conn_interval_min = le_conn_interval_min;
2588                             conn->le_conn_interval_max = le_conn_interval_max;
2589                             conn->le_conn_latency = le_conn_latency;
2590                             conn->le_supervision_timeout = le_supervision_timeout;
2591                         } else {
2592                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2593                         }
2594                     }
2595                     break;
2596                 default:
2597                     break;
2598             }
2599             break;
2600 #endif
2601         case HCI_EVENT_VENDOR_SPECIFIC:
2602             // Vendor specific commands often create vendor specific event instead of num completed packets
2603             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2604             switch (hci_stack->manufacturer){
2605                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2606                     hci_stack->num_cmd_packets = 1;
2607                     break;
2608                 default:
2609                     break;
2610             }
2611             break;
2612         default:
2613             break;
2614     }
2615 
2616     handle_event_for_current_stack_state(packet, size);
2617 
2618     // notify upper stack
2619 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2620 
2621     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2622     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2623         if (!packet[2]){
2624             handle = little_endian_read_16(packet, 3);
2625             hci_connection_t * aConn = hci_connection_for_handle(handle);
2626             if (aConn) {
2627                 uint8_t status = aConn->bonding_status;
2628                 uint16_t flags = aConn->bonding_flags;
2629                 bd_addr_t bd_address;
2630                 (void)memcpy(&bd_address, aConn->address, 6);
2631                 hci_shutdown_connection(aConn);
2632                 // connection struct is gone, don't access anymore
2633                 if (flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2634                     hci_emit_dedicated_bonding_result(bd_address, status);
2635                 }
2636             }
2637         }
2638     }
2639 
2640 	// execute main loop
2641 	hci_run();
2642 }
2643 
2644 #ifdef ENABLE_CLASSIC
2645 
2646 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2647 static void sco_schedule_tx(hci_connection_t * conn);
2648 
2649 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2650     log_debug("SCO TX Timeout");
2651     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2652     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2653     if (!conn) return;
2654 
2655     // trigger send
2656     conn->sco_tx_ready = 1;
2657     // extra packet if CVSD but SCO buffer is too short
2658     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2659         conn->sco_tx_ready++;
2660     }
2661     hci_notify_if_sco_can_send_now();
2662 }
2663 
2664 
2665 #define SCO_TX_AFTER_RX_MS (6)
2666 
2667 static void sco_schedule_tx(hci_connection_t * conn){
2668 
2669     uint32_t now = btstack_run_loop_get_time_ms();
2670     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2671     int time_delta_ms = sco_tx_ms - now;
2672 
2673     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2674 
2675     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2676     btstack_run_loop_set_timer(timer, time_delta_ms);
2677     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2678     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2679     btstack_run_loop_add_timer(timer);
2680 }
2681 
2682 static void sco_handler(uint8_t * packet, uint16_t size){
2683     // lookup connection struct
2684     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2685     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2686     if (!conn) return;
2687 
2688     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2689     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2690         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2691             packet[2] = 0x3c;
2692             memmove(&packet[3], &packet[23], 63);
2693             size = 63;
2694         }
2695     }
2696 
2697     if (hci_have_usb_transport()){
2698         // Nothing to do
2699     } else {
2700         // log_debug("sco flow %u, handle 0x%04x, packets sent %u, bytes send %u", hci_stack->synchronous_flow_control_enabled, (int) con_handle, conn->num_packets_sent, conn->num_sco_bytes_sent);
2701         if (hci_stack->synchronous_flow_control_enabled == 0){
2702             uint32_t now = btstack_run_loop_get_time_ms();
2703 
2704             if (!conn->sco_rx_valid){
2705                 // ignore first 10 packets
2706                 conn->sco_rx_count++;
2707                 // log_debug("sco rx count %u", conn->sco_rx_count);
2708                 if (conn->sco_rx_count == 10) {
2709                     // use first timestamp as is and pretent it just started
2710                     conn->sco_rx_ms = now;
2711                     conn->sco_rx_valid = 1;
2712                     conn->sco_rx_count = 0;
2713                     sco_schedule_tx(conn);
2714                 }
2715             } else {
2716                 // track expected arrival timme
2717                 conn->sco_rx_count++;
2718                 conn->sco_rx_ms += 7;
2719                 int delta = (int32_t) (now - conn->sco_rx_ms);
2720                 if (delta > 0){
2721                     conn->sco_rx_ms++;
2722                 }
2723                 // log_debug("sco rx %u", conn->sco_rx_ms);
2724                 sco_schedule_tx(conn);
2725             }
2726         }
2727     }
2728     // deliver to app
2729     if (hci_stack->sco_packet_handler) {
2730         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2731     }
2732 
2733 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2734     conn->num_packets_completed++;
2735     hci_stack->host_completed_packets = 1;
2736     hci_run();
2737 #endif
2738 }
2739 #endif
2740 
2741 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2742     hci_dump_packet(packet_type, 1, packet, size);
2743     switch (packet_type) {
2744         case HCI_EVENT_PACKET:
2745             event_handler(packet, size);
2746             break;
2747         case HCI_ACL_DATA_PACKET:
2748             acl_handler(packet, size);
2749             break;
2750 #ifdef ENABLE_CLASSIC
2751         case HCI_SCO_DATA_PACKET:
2752             sco_handler(packet, size);
2753             break;
2754 #endif
2755         default:
2756             break;
2757     }
2758 }
2759 
2760 /**
2761  * @brief Add event packet handler.
2762  */
2763 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2764     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2765 }
2766 
2767 
2768 /** Register HCI packet handlers */
2769 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2770     hci_stack->acl_packet_handler = handler;
2771 }
2772 
2773 #ifdef ENABLE_CLASSIC
2774 /**
2775  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2776  */
2777 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2778     hci_stack->sco_packet_handler = handler;
2779 }
2780 #endif
2781 
2782 static void hci_state_reset(void){
2783     // no connections yet
2784     hci_stack->connections = NULL;
2785 
2786     // keep discoverable/connectable as this has been requested by the client(s)
2787     // hci_stack->discoverable = 0;
2788     // hci_stack->connectable = 0;
2789     // hci_stack->bondable = 1;
2790     // hci_stack->own_addr_type = 0;
2791 
2792     // buffer is free
2793     hci_stack->hci_packet_buffer_reserved = 0;
2794 
2795     // no pending cmds
2796     hci_stack->decline_reason = 0;
2797     hci_stack->new_scan_enable_value = 0xff;
2798 
2799     // LE
2800 #ifdef ENABLE_BLE
2801     memset(hci_stack->le_random_address, 0, 6);
2802     hci_stack->le_random_address_set = 0;
2803 #endif
2804 #ifdef ENABLE_LE_CENTRAL
2805     hci_stack->le_scanning_active  = 0;
2806     hci_stack->le_scan_type = 0xff;
2807     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2808     hci_stack->le_whitelist = 0;
2809     hci_stack->le_whitelist_capacity = 0;
2810 #endif
2811 }
2812 
2813 #ifdef ENABLE_CLASSIC
2814 /**
2815  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2816  */
2817 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2818     // store and open remote device db
2819     hci_stack->link_key_db = link_key_db;
2820     if (hci_stack->link_key_db) {
2821         hci_stack->link_key_db->open();
2822     }
2823 }
2824 #endif
2825 
2826 void hci_init(const hci_transport_t *transport, const void *config){
2827 
2828 #ifdef HAVE_MALLOC
2829     if (!hci_stack) {
2830         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2831     }
2832 #else
2833     hci_stack = &hci_stack_static;
2834 #endif
2835     memset(hci_stack, 0, sizeof(hci_stack_t));
2836 
2837     // reference to use transport layer implementation
2838     hci_stack->hci_transport = transport;
2839 
2840     // reference to used config
2841     hci_stack->config = config;
2842 
2843     // setup pointer for outgoing packet buffer
2844     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2845 
2846     // max acl payload size defined in config.h
2847     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2848 
2849     // register packet handlers with transport
2850     transport->register_packet_handler(&packet_handler);
2851 
2852     hci_stack->state = HCI_STATE_OFF;
2853 
2854     // class of device
2855     hci_stack->class_of_device = 0x007a020c; // Smartphone
2856 
2857     // bondable by default
2858     hci_stack->bondable = 1;
2859 
2860 #ifdef ENABLE_CLASSIC
2861     // classic name
2862     hci_stack->local_name = default_classic_name;
2863 
2864     // Master slave policy
2865     hci_stack->master_slave_policy = 1;
2866 
2867     // Allow Role Switch
2868     hci_stack->allow_role_switch = 1;
2869 
2870     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2871     hci_stack->gap_required_encyrption_key_size = 16;
2872 #endif
2873 
2874     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2875     hci_stack->ssp_enable = 1;
2876     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2877     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2878     hci_stack->ssp_auto_accept = 1;
2879 
2880     // voice setting - signed 16 bit pcm data with CVSD over the air
2881     hci_stack->sco_voice_setting = 0x60;
2882 
2883 #ifdef ENABLE_LE_CENTRAL
2884     // connection parameter to use for outgoing connections
2885     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2886     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2887     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2888     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2889     hci_stack->le_connection_latency      = 4;         // 4
2890     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2891     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2892     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2893 
2894     // default LE Scanning
2895     hci_stack->le_scan_interval = 0x1e0;
2896     hci_stack->le_scan_window   =  0x30;
2897 #endif
2898 
2899 #ifdef ENABLE_LE_PERIPHERAL
2900     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2901 #endif
2902 
2903     // connection parameter range used to answer connection parameter update requests in l2cap
2904     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2905     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2906     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2907     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2908     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2909     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2910 
2911     hci_state_reset();
2912 }
2913 
2914 /**
2915  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2916  */
2917 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2918     hci_stack->chipset = chipset_driver;
2919 
2920     // reset chipset driver - init is also called on power_up
2921     if (hci_stack->chipset && hci_stack->chipset->init){
2922         hci_stack->chipset->init(hci_stack->config);
2923     }
2924 }
2925 
2926 /**
2927  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2928  */
2929 void hci_set_control(const btstack_control_t *hardware_control){
2930     // references to used control implementation
2931     hci_stack->control = hardware_control;
2932     // init with transport config
2933     hardware_control->init(hci_stack->config);
2934 }
2935 
2936 void hci_close(void){
2937     // close remote device db
2938     if (hci_stack->link_key_db) {
2939         hci_stack->link_key_db->close();
2940     }
2941 
2942     btstack_linked_list_iterator_t lit;
2943     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2944     while (btstack_linked_list_iterator_has_next(&lit)){
2945         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2946         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2947         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2948         hci_shutdown_connection(connection);
2949     }
2950 
2951     hci_power_control(HCI_POWER_OFF);
2952 
2953 #ifdef HAVE_MALLOC
2954     free(hci_stack);
2955 #endif
2956     hci_stack = NULL;
2957 }
2958 
2959 #ifdef ENABLE_CLASSIC
2960 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
2961     // validate ranage and set
2962     if (encryption_key_size < 7)  return;
2963     if (encryption_key_size > 16) return;
2964     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
2965 }
2966 #endif
2967 
2968 #ifdef ENABLE_CLASSIC
2969 void gap_set_class_of_device(uint32_t class_of_device){
2970     hci_stack->class_of_device = class_of_device;
2971 }
2972 
2973 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
2974     hci_stack->default_link_policy_settings = default_link_policy_settings;
2975 }
2976 
2977 void gap_set_allow_role_switch(bool allow_role_switch){
2978     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
2979 }
2980 
2981 uint8_t hci_get_allow_role_switch(void){
2982     return  hci_stack->allow_role_switch;
2983 }
2984 
2985 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
2986     hci_stack->link_supervision_timeout = link_supervision_timeout;
2987 }
2988 
2989 void hci_disable_l2cap_timeout_check(void){
2990     disable_l2cap_timeouts = 1;
2991 }
2992 #endif
2993 
2994 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
2995 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
2996 void hci_set_bd_addr(bd_addr_t addr){
2997     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
2998     hci_stack->custom_bd_addr_set = 1;
2999 }
3000 #endif
3001 
3002 // State-Module-Driver overview
3003 // state                    module  low-level
3004 // HCI_STATE_OFF             off      close
3005 // HCI_STATE_INITIALIZING,   on       open
3006 // HCI_STATE_WORKING,        on       open
3007 // HCI_STATE_HALTING,        on       open
3008 // HCI_STATE_SLEEPING,    off/sleep   close
3009 // HCI_STATE_FALLING_ASLEEP  on       open
3010 
3011 static int hci_power_control_on(void){
3012 
3013     // power on
3014     int err = 0;
3015     if (hci_stack->control && hci_stack->control->on){
3016         err = (*hci_stack->control->on)();
3017     }
3018     if (err){
3019         log_error( "POWER_ON failed");
3020         hci_emit_hci_open_failed();
3021         return err;
3022     }
3023 
3024     // int chipset driver
3025     if (hci_stack->chipset && hci_stack->chipset->init){
3026         hci_stack->chipset->init(hci_stack->config);
3027     }
3028 
3029     // init transport
3030     if (hci_stack->hci_transport->init){
3031         hci_stack->hci_transport->init(hci_stack->config);
3032     }
3033 
3034     // open transport
3035     err = hci_stack->hci_transport->open();
3036     if (err){
3037         log_error( "HCI_INIT failed, turning Bluetooth off again");
3038         if (hci_stack->control && hci_stack->control->off){
3039             (*hci_stack->control->off)();
3040         }
3041         hci_emit_hci_open_failed();
3042         return err;
3043     }
3044     return 0;
3045 }
3046 
3047 static void hci_power_control_off(void){
3048 
3049     log_info("hci_power_control_off");
3050 
3051     // close low-level device
3052     hci_stack->hci_transport->close();
3053 
3054     log_info("hci_power_control_off - hci_transport closed");
3055 
3056     // power off
3057     if (hci_stack->control && hci_stack->control->off){
3058         (*hci_stack->control->off)();
3059     }
3060 
3061     log_info("hci_power_control_off - control closed");
3062 
3063     hci_stack->state = HCI_STATE_OFF;
3064 }
3065 
3066 static void hci_power_control_sleep(void){
3067 
3068     log_info("hci_power_control_sleep");
3069 
3070 #if 0
3071     // don't close serial port during sleep
3072 
3073     // close low-level device
3074     hci_stack->hci_transport->close(hci_stack->config);
3075 #endif
3076 
3077     // sleep mode
3078     if (hci_stack->control && hci_stack->control->sleep){
3079         (*hci_stack->control->sleep)();
3080     }
3081 
3082     hci_stack->state = HCI_STATE_SLEEPING;
3083 }
3084 
3085 static int hci_power_control_wake(void){
3086 
3087     log_info("hci_power_control_wake");
3088 
3089     // wake on
3090     if (hci_stack->control && hci_stack->control->wake){
3091         (*hci_stack->control->wake)();
3092     }
3093 
3094 #if 0
3095     // open low-level device
3096     int err = hci_stack->hci_transport->open(hci_stack->config);
3097     if (err){
3098         log_error( "HCI_INIT failed, turning Bluetooth off again");
3099         if (hci_stack->control && hci_stack->control->off){
3100             (*hci_stack->control->off)();
3101         }
3102         hci_emit_hci_open_failed();
3103         return err;
3104     }
3105 #endif
3106 
3107     return 0;
3108 }
3109 
3110 static void hci_power_transition_to_initializing(void){
3111     // set up state machine
3112     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3113     hci_stack->hci_packet_buffer_reserved = 0;
3114     hci_stack->state = HCI_STATE_INITIALIZING;
3115     hci_stack->substate = HCI_INIT_SEND_RESET;
3116 }
3117 
3118 int hci_power_control(HCI_POWER_MODE power_mode){
3119 
3120     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3121 
3122     int err = 0;
3123     switch (hci_stack->state){
3124 
3125         case HCI_STATE_OFF:
3126             switch (power_mode){
3127                 case HCI_POWER_ON:
3128                     err = hci_power_control_on();
3129                     if (err) {
3130                         log_error("hci_power_control_on() error %d", err);
3131                         return err;
3132                     }
3133                     hci_power_transition_to_initializing();
3134                     break;
3135                 case HCI_POWER_OFF:
3136                     // do nothing
3137                     break;
3138                 case HCI_POWER_SLEEP:
3139                     // do nothing (with SLEEP == OFF)
3140                     break;
3141             }
3142             break;
3143 
3144         case HCI_STATE_INITIALIZING:
3145             switch (power_mode){
3146                 case HCI_POWER_ON:
3147                     // do nothing
3148                     break;
3149                 case HCI_POWER_OFF:
3150                     // no connections yet, just turn it off
3151                     hci_power_control_off();
3152                     break;
3153                 case HCI_POWER_SLEEP:
3154                     // no connections yet, just turn it off
3155                     hci_power_control_sleep();
3156                     break;
3157             }
3158             break;
3159 
3160         case HCI_STATE_WORKING:
3161             switch (power_mode){
3162                 case HCI_POWER_ON:
3163                     // do nothing
3164                     break;
3165                 case HCI_POWER_OFF:
3166                     // see hci_run
3167                     hci_stack->state = HCI_STATE_HALTING;
3168                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3169                     break;
3170                 case HCI_POWER_SLEEP:
3171                     // see hci_run
3172                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3173                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3174                     break;
3175             }
3176             break;
3177 
3178         case HCI_STATE_HALTING:
3179             switch (power_mode){
3180                 case HCI_POWER_ON:
3181                     hci_power_transition_to_initializing();
3182                     break;
3183                 case HCI_POWER_OFF:
3184                     // do nothing
3185                     break;
3186                 case HCI_POWER_SLEEP:
3187                     // see hci_run
3188                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3189                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3190                     break;
3191             }
3192             break;
3193 
3194         case HCI_STATE_FALLING_ASLEEP:
3195             switch (power_mode){
3196                 case HCI_POWER_ON:
3197 
3198 #ifdef HAVE_PLATFORM_IPHONE_OS
3199                     // nothing to do, if H4 supports power management
3200                     if (btstack_control_iphone_power_management_enabled()){
3201                         hci_stack->state = HCI_STATE_INITIALIZING;
3202                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3203                         break;
3204                     }
3205 #endif
3206                     hci_power_transition_to_initializing();
3207                     break;
3208                 case HCI_POWER_OFF:
3209                     // see hci_run
3210                     hci_stack->state = HCI_STATE_HALTING;
3211                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3212                     break;
3213                 case HCI_POWER_SLEEP:
3214                     // do nothing
3215                     break;
3216             }
3217             break;
3218 
3219         case HCI_STATE_SLEEPING:
3220             switch (power_mode){
3221                 case HCI_POWER_ON:
3222 
3223 #ifdef HAVE_PLATFORM_IPHONE_OS
3224                     // nothing to do, if H4 supports power management
3225                     if (btstack_control_iphone_power_management_enabled()){
3226                         hci_stack->state = HCI_STATE_INITIALIZING;
3227                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3228                         hci_update_scan_enable();
3229                         break;
3230                     }
3231 #endif
3232                     err = hci_power_control_wake();
3233                     if (err) return err;
3234                     hci_power_transition_to_initializing();
3235                     break;
3236                 case HCI_POWER_OFF:
3237                     hci_stack->state = HCI_STATE_HALTING;
3238                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3239                     break;
3240                 case HCI_POWER_SLEEP:
3241                     // do nothing
3242                     break;
3243             }
3244             break;
3245     }
3246 
3247     // create internal event
3248 	hci_emit_state();
3249 
3250 	// trigger next/first action
3251 	hci_run();
3252 
3253     return 0;
3254 }
3255 
3256 
3257 #ifdef ENABLE_CLASSIC
3258 
3259 static void hci_update_scan_enable(void){
3260     // 2 = page scan, 1 = inq scan
3261     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3262     hci_run();
3263 }
3264 
3265 void gap_discoverable_control(uint8_t enable){
3266     if (enable) enable = 1; // normalize argument
3267 
3268     if (hci_stack->discoverable == enable){
3269         hci_emit_discoverable_enabled(hci_stack->discoverable);
3270         return;
3271     }
3272 
3273     hci_stack->discoverable = enable;
3274     hci_update_scan_enable();
3275 }
3276 
3277 void gap_connectable_control(uint8_t enable){
3278     if (enable) enable = 1; // normalize argument
3279 
3280     // don't emit event
3281     if (hci_stack->connectable == enable) return;
3282 
3283     hci_stack->connectable = enable;
3284     hci_update_scan_enable();
3285 }
3286 #endif
3287 
3288 void gap_local_bd_addr(bd_addr_t address_buffer){
3289     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3290 }
3291 
3292 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3293 static void hci_host_num_completed_packets(void){
3294 
3295     // create packet manually as arrays are not supported and num_commands should not get reduced
3296     hci_reserve_packet_buffer();
3297     uint8_t * packet = hci_get_outgoing_packet_buffer();
3298 
3299     uint16_t size = 0;
3300     uint16_t num_handles = 0;
3301     packet[size++] = 0x35;
3302     packet[size++] = 0x0c;
3303     size++;  // skip param len
3304     size++;  // skip num handles
3305 
3306     // add { handle, packets } entries
3307     btstack_linked_item_t * it;
3308     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3309         hci_connection_t * connection = (hci_connection_t *) it;
3310         if (connection->num_packets_completed){
3311             little_endian_store_16(packet, size, connection->con_handle);
3312             size += 2;
3313             little_endian_store_16(packet, size, connection->num_packets_completed);
3314             size += 2;
3315             //
3316             num_handles++;
3317             connection->num_packets_completed = 0;
3318         }
3319     }
3320 
3321     packet[2] = size - 3;
3322     packet[3] = num_handles;
3323 
3324     hci_stack->host_completed_packets = 0;
3325 
3326     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3327     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3328 
3329     // release packet buffer for synchronous transport implementations
3330     if (hci_transport_synchronous()){
3331         hci_release_packet_buffer();
3332         hci_emit_transport_packet_sent();
3333     }
3334 }
3335 #endif
3336 
3337 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3338     UNUSED(ds);
3339     hci_stack->substate = HCI_HALTING_CLOSE;
3340     // allow packet handlers to defer final shutdown
3341     hci_emit_state();
3342     hci_run();
3343 }
3344 
3345 static bool hci_run_acl_fragments(void){
3346     if (hci_stack->acl_fragmentation_total_size > 0) {
3347         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3348         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3349         if (connection) {
3350             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3351                 hci_send_acl_packet_fragments(connection);
3352                 return true;
3353             }
3354         } else {
3355             // connection gone -> discard further fragments
3356             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3357             hci_stack->acl_fragmentation_total_size = 0;
3358             hci_stack->acl_fragmentation_pos = 0;
3359         }
3360     }
3361     return false;
3362 }
3363 
3364 #ifdef ENABLE_CLASSIC
3365 static bool hci_run_general_gap_classic(void){
3366 
3367     // decline incoming connections
3368     if (hci_stack->decline_reason){
3369         uint8_t reason = hci_stack->decline_reason;
3370         hci_stack->decline_reason = 0;
3371         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3372         return true;
3373     }
3374     // send scan enable
3375     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3376         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3377         hci_stack->new_scan_enable_value = 0xff;
3378         return true;
3379     }
3380     // start/stop inquiry
3381     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3382         uint8_t duration = hci_stack->inquiry_state;
3383         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3384         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3385         return true;
3386     }
3387     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3388         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3389         hci_send_cmd(&hci_inquiry_cancel);
3390         return true;
3391     }
3392     // remote name request
3393     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3394         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3395         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3396                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3397         return true;
3398     }
3399     // pairing
3400     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3401         uint8_t state = hci_stack->gap_pairing_state;
3402         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3403         switch (state){
3404             case GAP_PAIRING_STATE_SEND_PIN:
3405                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, strlen(hci_stack->gap_pairing_input.gap_pairing_pin), hci_stack->gap_pairing_input.gap_pairing_pin);
3406                 break;
3407             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3408                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3409                 break;
3410             case GAP_PAIRING_STATE_SEND_PASSKEY:
3411                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3412                 break;
3413             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3414                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3415                 break;
3416             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3417                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3418                 break;
3419             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3420                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3421                 break;
3422             default:
3423                 break;
3424         }
3425         return true;
3426     }
3427     return false;
3428 }
3429 #endif
3430 
3431 #ifdef ENABLE_BLE
3432 static bool hci_run_general_gap_le(void){
3433 
3434     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3435 
3436     if (hci_stack->state != HCI_STATE_WORKING) return false;
3437     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3438 
3439 #ifdef ENABLE_LE_CENTRAL
3440     // parameter change requires scanning to be stopped first
3441     if (hci_stack->le_scan_type != 0xff) {
3442         if (hci_stack->le_scanning_active){
3443             hci_stack->le_scanning_active = 0;
3444             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3445         } else {
3446             int scan_type = (int) hci_stack->le_scan_type;
3447             hci_stack->le_scan_type = 0xff;
3448             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
3449         }
3450         return true;
3451     }
3452     // finally, we can enable/disable le scan
3453     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3454         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3455         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3456         return true;
3457     }
3458 #endif
3459 #ifdef ENABLE_LE_PERIPHERAL
3460     // le advertisement control
3461     if (hci_stack->le_advertisements_todo){
3462         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3463     }
3464     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3465         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3466         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3467         return true;
3468     }
3469     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3470         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3471         hci_send_cmd(&hci_le_set_advertising_parameters,
3472                      hci_stack->le_advertisements_interval_min,
3473                      hci_stack->le_advertisements_interval_max,
3474                      hci_stack->le_advertisements_type,
3475                      hci_stack->le_own_addr_type,
3476                      hci_stack->le_advertisements_direct_address_type,
3477                      hci_stack->le_advertisements_direct_address,
3478                      hci_stack->le_advertisements_channel_map,
3479                      hci_stack->le_advertisements_filter_policy);
3480         return true;
3481     }
3482     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3483         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3484         uint8_t adv_data_clean[31];
3485         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3486         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3487                      hci_stack->le_advertisements_data_len);
3488         hci_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len);
3489         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3490         return true;
3491     }
3492     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3493         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3494         uint8_t scan_data_clean[31];
3495         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3496         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3497                      hci_stack->le_scan_response_data_len);
3498         hci_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len);
3499         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3500         return true;
3501     }
3502     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3503         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3504         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3505         return true;
3506     }
3507 #endif
3508 
3509 #ifdef ENABLE_LE_CENTRAL
3510     //
3511     // LE Whitelist Management
3512     //
3513 
3514     // check if whitelist needs modification
3515     btstack_linked_list_iterator_t lit;
3516     int modification_pending = 0;
3517     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3518     while (btstack_linked_list_iterator_has_next(&lit)){
3519         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3520         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3521             modification_pending = 1;
3522             break;
3523         }
3524     }
3525 
3526     if (modification_pending){
3527         // stop connnecting if modification pending
3528         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3529             hci_send_cmd(&hci_le_create_connection_cancel);
3530             return true;
3531         }
3532 
3533         // add/remove entries
3534         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3535         while (btstack_linked_list_iterator_has_next(&lit)){
3536             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3537             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3538                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3539                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3540                 return true;
3541             }
3542             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3543                 bd_addr_t address;
3544                 bd_addr_type_t address_type = entry->address_type;
3545                 (void)memcpy(address, entry->address, 6);
3546                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3547                 btstack_memory_whitelist_entry_free(entry);
3548                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3549                 return true;
3550             }
3551         }
3552     }
3553 
3554     // start connecting
3555     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3556          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3557         bd_addr_t null_addr;
3558         memset(null_addr, 0, 6);
3559         hci_send_cmd(&hci_le_create_connection,
3560                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3561                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3562                      1,         // use whitelist
3563                      0,         // peer address type
3564                      null_addr, // peer bd addr
3565                      hci_stack->le_own_addr_type, // our addr type:
3566                      hci_stack->le_connection_interval_min,    // conn interval min
3567                      hci_stack->le_connection_interval_max,    // conn interval max
3568                      hci_stack->le_connection_latency,         // conn latency
3569                      hci_stack->le_supervision_timeout,        // conn latency
3570                      hci_stack->le_minimum_ce_length,          // min ce length
3571                      hci_stack->le_maximum_ce_length           // max ce length
3572         );
3573         return true;
3574     }
3575 #endif
3576     return false;
3577 }
3578 #endif
3579 
3580 static bool hci_run_general_pending_commmands(void){
3581     btstack_linked_item_t * it;
3582     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3583         hci_connection_t * connection = (hci_connection_t *) it;
3584 
3585         switch(connection->state){
3586             case SEND_CREATE_CONNECTION:
3587                 switch(connection->address_type){
3588 #ifdef ENABLE_CLASSIC
3589                     case BD_ADDR_TYPE_ACL:
3590                         log_info("sending hci_create_connection");
3591                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3592                         break;
3593 #endif
3594                     default:
3595 #ifdef ENABLE_BLE
3596 #ifdef ENABLE_LE_CENTRAL
3597                         // track outgoing connection
3598                         hci_stack->outgoing_addr_type = connection->address_type;
3599                         (void)memcpy(hci_stack->outgoing_addr,
3600                                      connection->address, 6);
3601                         log_info("sending hci_le_create_connection");
3602                         hci_send_cmd(&hci_le_create_connection,
3603                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3604                                      hci_stack->le_connection_scan_window,      // conn scan windows
3605                                      0,         // don't use whitelist
3606                                      connection->address_type, // peer address type
3607                                      connection->address,      // peer bd addr
3608                                      hci_stack->le_own_addr_type, // our addr type:
3609                                      hci_stack->le_connection_interval_min,    // conn interval min
3610                                      hci_stack->le_connection_interval_max,    // conn interval max
3611                                      hci_stack->le_connection_latency,         // conn latency
3612                                      hci_stack->le_supervision_timeout,        // conn latency
3613                                      hci_stack->le_minimum_ce_length,          // min ce length
3614                                      hci_stack->le_maximum_ce_length          // max ce length
3615                         );
3616                         connection->state = SENT_CREATE_CONNECTION;
3617 #endif
3618 #endif
3619                         break;
3620                 }
3621                 return true;
3622 
3623 #ifdef ENABLE_CLASSIC
3624             case RECEIVED_CONNECTION_REQUEST:
3625                 connection->role  = HCI_ROLE_SLAVE;
3626                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3627                     log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
3628                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3629                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3630                 }
3631                 return true;
3632 #endif
3633 
3634 #ifdef ENABLE_BLE
3635 #ifdef ENABLE_LE_CENTRAL
3636             case SEND_CANCEL_CONNECTION:
3637                 connection->state = SENT_CANCEL_CONNECTION;
3638                 hci_send_cmd(&hci_le_create_connection_cancel);
3639                 return true;
3640 #endif
3641 #endif
3642             case SEND_DISCONNECT:
3643                 connection->state = SENT_DISCONNECT;
3644                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3645                 return true;
3646 
3647             default:
3648                 break;
3649         }
3650 
3651         // no further commands if connection is about to get shut down
3652         if (connection->state == SENT_DISCONNECT) continue;
3653 
3654         if (connection->authentication_flags & READ_RSSI){
3655             connectionClearAuthenticationFlags(connection, READ_RSSI);
3656             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3657             return true;
3658         }
3659 
3660 #ifdef ENABLE_CLASSIC
3661 
3662         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3663             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3664             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3665             return true;
3666         }
3667 
3668         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3669             log_info("responding to link key request");
3670             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3671             link_key_t link_key;
3672             link_key_type_t link_key_type;
3673             if ( hci_stack->link_key_db
3674                  && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3675                  && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level)){
3676                 connection->link_key_type = link_key_type;
3677                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3678             } else {
3679                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3680             }
3681             return true;
3682         }
3683 
3684         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3685             log_info("denying to pin request");
3686             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3687             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3688             return true;
3689         }
3690 
3691         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3692             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3693             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3694             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3695                 // tweak authentication requirements
3696                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3697                 if (connection->bonding_flags & BONDING_DEDICATED){
3698                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3699                 }
3700                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3701                     authreq |= 1;
3702                 }
3703                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3704             } else {
3705                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3706             }
3707             return true;
3708         }
3709 
3710         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3711             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3712             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3713             return true;
3714         }
3715 
3716         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3717             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3718             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3719             return true;
3720         }
3721 
3722         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
3723             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
3724             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3725             return true;
3726         }
3727 
3728         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3729             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3730             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3731             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3732             return true;
3733         }
3734 
3735         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3736             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3737             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3738             return true;
3739         }
3740 
3741         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3742             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3743             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3744             return true;
3745         }
3746         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3747             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3748             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3749             return true;
3750         }
3751 #endif
3752 
3753         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3754             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3755             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3756             return true;
3757         }
3758 
3759 #ifdef ENABLE_CLASSIC
3760         uint16_t sniff_min_interval;
3761         switch (connection->sniff_min_interval){
3762             case 0:
3763                 break;
3764             case 0xffff:
3765                 connection->sniff_min_interval = 0;
3766                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3767                 return true;
3768             default:
3769                 sniff_min_interval = connection->sniff_min_interval;
3770                 connection->sniff_min_interval = 0;
3771                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3772                 return true;
3773         }
3774 #endif
3775 
3776 #ifdef ENABLE_BLE
3777         switch (connection->le_con_parameter_update_state){
3778             // response to L2CAP CON PARAMETER UPDATE REQUEST
3779             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3780                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3781                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3782                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3783                              0x0000, 0xffff);
3784                 return true;
3785             case CON_PARAMETER_UPDATE_REPLY:
3786                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3787                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3788                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3789                              0x0000, 0xffff);
3790                 return true;
3791             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3792                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3793                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3794                 return true;
3795             default:
3796                 break;
3797         }
3798         if (connection->le_phy_update_all_phys != 0xff){
3799             uint8_t all_phys = connection->le_phy_update_all_phys;
3800             connection->le_phy_update_all_phys = 0xff;
3801             hci_send_cmd(&hci_le_set_phy, connection->con_handle, all_phys, connection->le_phy_update_tx_phys, connection->le_phy_update_rx_phys, connection->le_phy_update_phy_options);
3802             return true;
3803         }
3804 #endif
3805     }
3806     return false;
3807 }
3808 
3809 static void hci_run(void){
3810 
3811     bool done;
3812 
3813     // send continuation fragments first, as they block the prepared packet buffer
3814     done = hci_run_acl_fragments();
3815     if (done) return;
3816 
3817 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3818     // send host num completed packets next as they don't require num_cmd_packets > 0
3819     if (!hci_can_send_comand_packet_transport()) return;
3820     if (hci_stack->host_completed_packets){
3821         hci_host_num_completed_packets();
3822         return;
3823     }
3824 #endif
3825 
3826     if (!hci_can_send_command_packet_now()) return;
3827 
3828     // global/non-connection oriented commands
3829 
3830 
3831 #ifdef ENABLE_CLASSIC
3832     // general gap classic
3833     done = hci_run_general_gap_classic();
3834     if (done) return;
3835 #endif
3836 
3837 #ifdef ENABLE_BLE
3838     // general gap le
3839     done = hci_run_general_gap_le();
3840     if (done) return;
3841 #endif
3842 
3843     // send pending HCI commands
3844     done = hci_run_general_pending_commmands();
3845     if (done) return;
3846 
3847     // stack state sub statemachines
3848     hci_connection_t * connection;
3849     switch (hci_stack->state){
3850         case HCI_STATE_INITIALIZING:
3851             hci_initializing_run();
3852             break;
3853 
3854         case HCI_STATE_HALTING:
3855 
3856             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3857             switch (hci_stack->substate){
3858                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3859                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3860 
3861 #ifdef ENABLE_BLE
3862 #ifdef ENABLE_LE_CENTRAL
3863                     // free whitelist entries
3864                     {
3865                         btstack_linked_list_iterator_t lit;
3866                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3867                         while (btstack_linked_list_iterator_has_next(&lit)){
3868                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3869                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3870                             btstack_memory_whitelist_entry_free(entry);
3871                         }
3872                     }
3873 #endif
3874 #endif
3875                     // close all open connections
3876                     connection =  (hci_connection_t *) hci_stack->connections;
3877                     if (connection){
3878                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3879                         if (!hci_can_send_command_packet_now()) return;
3880 
3881                         // check state
3882                         if (connection->state == SENT_DISCONNECT) return;
3883                         connection->state = SENT_DISCONNECT;
3884 
3885                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3886 
3887                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3888                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3889 
3890                         // ... which would be ignored anyway as we shutdown (free) the connection now
3891                         hci_shutdown_connection(connection);
3892 
3893                         // finally, send the disconnect command
3894                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3895                         return;
3896                     }
3897 
3898                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
3899                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
3900                         log_info("HCI_STATE_HALTING: wait 50 ms");
3901                         hci_stack->substate = HCI_HALTING_W4_TIMER;
3902                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
3903                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3904                         btstack_run_loop_add_timer(&hci_stack->timeout);
3905                         break;
3906                     }
3907 
3908                     /* fall through */
3909 
3910                 case HCI_HALTING_CLOSE:
3911                     log_info("HCI_STATE_HALTING, calling off");
3912 
3913                     // switch mode
3914                     hci_power_control_off();
3915 
3916                     log_info("HCI_STATE_HALTING, emitting state");
3917                     hci_emit_state();
3918                     log_info("HCI_STATE_HALTING, done");
3919                     break;
3920 
3921                 case HCI_HALTING_W4_TIMER:
3922                     // keep waiting
3923 
3924                     break;
3925                 default:
3926                     break;
3927             }
3928 
3929             break;
3930 
3931         case HCI_STATE_FALLING_ASLEEP:
3932             switch(hci_stack->substate) {
3933                 case HCI_FALLING_ASLEEP_DISCONNECT:
3934                     log_info("HCI_STATE_FALLING_ASLEEP");
3935                     // close all open connections
3936                     connection =  (hci_connection_t *) hci_stack->connections;
3937 
3938 #ifdef HAVE_PLATFORM_IPHONE_OS
3939                     // don't close connections, if H4 supports power management
3940                     if (btstack_control_iphone_power_management_enabled()){
3941                         connection = NULL;
3942                     }
3943 #endif
3944                     if (connection){
3945 
3946                         // send disconnect
3947                         if (!hci_can_send_command_packet_now()) return;
3948 
3949                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
3950                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
3951 
3952                         // send disconnected event right away - causes higher layer connections to get closed, too.
3953                         hci_shutdown_connection(connection);
3954                         return;
3955                     }
3956 
3957                     if (hci_classic_supported()){
3958                         // disable page and inquiry scan
3959                         if (!hci_can_send_command_packet_now()) return;
3960 
3961                         log_info("HCI_STATE_HALTING, disabling inq scans");
3962                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
3963 
3964                         // continue in next sub state
3965                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
3966                         break;
3967                     }
3968 
3969                     /* fall through */
3970 
3971                 case HCI_FALLING_ASLEEP_COMPLETE:
3972                     log_info("HCI_STATE_HALTING, calling sleep");
3973 #ifdef HAVE_PLATFORM_IPHONE_OS
3974                     // don't actually go to sleep, if H4 supports power management
3975                     if (btstack_control_iphone_power_management_enabled()){
3976                         // SLEEP MODE reached
3977                         hci_stack->state = HCI_STATE_SLEEPING;
3978                         hci_emit_state();
3979                         break;
3980                     }
3981 #endif
3982                     // switch mode
3983                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
3984                     hci_emit_state();
3985                     break;
3986 
3987                 default:
3988                     break;
3989             }
3990             break;
3991 
3992         default:
3993             break;
3994     }
3995 }
3996 
3997 int hci_send_cmd_packet(uint8_t *packet, int size){
3998     // house-keeping
3999 
4000     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4001         hci_stack->loopback_mode = packet[3];
4002     }
4003 
4004 #ifdef ENABLE_CLASSIC
4005     bd_addr_t addr;
4006     hci_connection_t * conn;
4007 
4008     // create_connection?
4009     if (IS_COMMAND(packet, hci_create_connection)){
4010         reverse_bd_addr(&packet[3], addr);
4011         log_info("Create_connection to %s", bd_addr_to_str(addr));
4012 
4013         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4014         if (!conn){
4015             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4016             if (!conn){
4017                 // notify client that alloc failed
4018                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4019                 return -1; // packet not sent to controller
4020             }
4021             conn->state = SEND_CREATE_CONNECTION;
4022         }
4023         log_info("conn state %u", conn->state);
4024         switch (conn->state){
4025             // if connection active exists
4026             case OPEN:
4027                 // and OPEN, emit connection complete command
4028                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4029                 return -1; // packet not sent to controller
4030             case SEND_CREATE_CONNECTION:
4031                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4032                 break;
4033             default:
4034                 // otherwise, just ignore as it is already in the open process
4035                 return -1; // packet not sent to controller
4036         }
4037         conn->state = SENT_CREATE_CONNECTION;
4038 
4039         // track outgoing connection
4040         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4041         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4042     }
4043 
4044     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4045         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4046     }
4047     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4048         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4049     }
4050 
4051     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4052         if (hci_stack->link_key_db){
4053             reverse_bd_addr(&packet[3], addr);
4054             hci_stack->link_key_db->delete_link_key(addr);
4055         }
4056     }
4057 
4058     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4059     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4060         reverse_bd_addr(&packet[3], addr);
4061         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4062         if (conn){
4063             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4064         }
4065     }
4066 
4067     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4068     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4069     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4070     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4071         reverse_bd_addr(&packet[3], addr);
4072         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4073         if (conn){
4074             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4075         }
4076     }
4077 
4078 #ifdef ENABLE_SCO_OVER_HCI
4079     // setup_synchronous_connection? Voice setting at offset 22
4080     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4081         // TODO: compare to current setting if sco connection already active
4082         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4083     }
4084     // accept_synchronus_connection? Voice setting at offset 18
4085     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4086         // TODO: compare to current setting if sco connection already active
4087         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4088     }
4089 #endif
4090 #endif
4091 
4092 #ifdef ENABLE_BLE
4093     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4094         hci_stack->le_random_address_set = 1;
4095         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4096     }
4097 #ifdef ENABLE_LE_PERIPHERAL
4098     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4099         hci_stack->le_advertisements_active = packet[3];
4100     }
4101 #endif
4102 #ifdef ENABLE_LE_CENTRAL
4103     else if (IS_COMMAND(packet, hci_le_create_connection)){
4104         // white list used?
4105         uint8_t initiator_filter_policy = packet[7];
4106         switch (initiator_filter_policy){
4107             case 0:
4108                 // whitelist not used
4109                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4110                 break;
4111             case 1:
4112                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4113                 break;
4114             default:
4115                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4116                 break;
4117         }
4118     }
4119     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4120         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4121     }
4122 #endif
4123 #endif
4124 
4125     hci_stack->num_cmd_packets--;
4126 
4127     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4128     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4129 }
4130 
4131 // disconnect because of security block
4132 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4133     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4134     if (!connection) return;
4135     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4136 }
4137 
4138 
4139 // Configure Secure Simple Pairing
4140 
4141 #ifdef ENABLE_CLASSIC
4142 
4143 // enable will enable SSP during init
4144 void gap_ssp_set_enable(int enable){
4145     hci_stack->ssp_enable = enable;
4146 }
4147 
4148 static int hci_local_ssp_activated(void){
4149     return gap_ssp_supported() && hci_stack->ssp_enable;
4150 }
4151 
4152 // if set, BTstack will respond to io capability request using authentication requirement
4153 void gap_ssp_set_io_capability(int io_capability){
4154     hci_stack->ssp_io_capability = io_capability;
4155 }
4156 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4157     hci_stack->ssp_authentication_requirement = authentication_requirement;
4158 }
4159 
4160 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4161 void gap_ssp_set_auto_accept(int auto_accept){
4162     hci_stack->ssp_auto_accept = auto_accept;
4163 }
4164 #endif
4165 
4166 // va_list part of hci_send_cmd
4167 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4168     if (!hci_can_send_command_packet_now()){
4169         log_error("hci_send_cmd called but cannot send packet now");
4170         return 0;
4171     }
4172 
4173     // for HCI INITIALIZATION
4174     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4175     hci_stack->last_cmd_opcode = cmd->opcode;
4176 
4177     hci_reserve_packet_buffer();
4178     uint8_t * packet = hci_stack->hci_packet_buffer;
4179     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4180     int err = hci_send_cmd_packet(packet, size);
4181 
4182     // release packet buffer for synchronous transport implementations
4183     if (hci_transport_synchronous()){
4184         hci_release_packet_buffer();
4185         hci_emit_transport_packet_sent();
4186     }
4187 
4188     return err;
4189 }
4190 
4191 /**
4192  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4193  */
4194 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4195     va_list argptr;
4196     va_start(argptr, cmd);
4197     int res = hci_send_cmd_va_arg(cmd, argptr);
4198     va_end(argptr);
4199     return res;
4200 }
4201 
4202 // Create various non-HCI events.
4203 // TODO: generalize, use table similar to hci_create_command
4204 
4205 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4206     // dump packet
4207     if (dump) {
4208         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4209     }
4210 
4211     // dispatch to all event handlers
4212     btstack_linked_list_iterator_t it;
4213     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4214     while (btstack_linked_list_iterator_has_next(&it)){
4215         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4216         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4217     }
4218 }
4219 
4220 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4221     if (!hci_stack->acl_packet_handler) return;
4222     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4223 }
4224 
4225 #ifdef ENABLE_CLASSIC
4226 static void hci_notify_if_sco_can_send_now(void){
4227     // notify SCO sender if waiting
4228     if (!hci_stack->sco_waiting_for_can_send_now) return;
4229     if (hci_can_send_sco_packet_now()){
4230         hci_stack->sco_waiting_for_can_send_now = 0;
4231         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4232         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4233         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4234     }
4235 }
4236 
4237 // parsing end emitting has been merged to reduce code size
4238 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4239     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4240 
4241     uint8_t * eir_data;
4242     ad_context_t context;
4243     const uint8_t * name;
4244     uint8_t         name_len;
4245 
4246     if (size < 3) return;
4247 
4248     int event_type = hci_event_packet_get_type(packet);
4249     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4250     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4251 
4252     switch (event_type){
4253         case HCI_EVENT_INQUIRY_RESULT:
4254         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4255             if (size != (3 + (num_responses * 14))) return;
4256             break;
4257         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4258             if (size != 257) return;
4259             if (num_responses != 1) return;
4260             break;
4261         default:
4262             return;
4263     }
4264 
4265     // event[1] is set at the end
4266     int i;
4267     for (i=0; i<num_responses;i++){
4268         memset(event, 0, sizeof(event));
4269         event[0] = GAP_EVENT_INQUIRY_RESULT;
4270         uint8_t event_size = 18;    // if name is not set by EIR
4271 
4272         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4273         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4274         (void)memcpy(&event[9],
4275                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4276                      3); // class of device
4277         (void)memcpy(&event[12],
4278                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4279                      2); // clock offset
4280 
4281         switch (event_type){
4282             case HCI_EVENT_INQUIRY_RESULT:
4283                 // 14,15,16,17 = 0, size 18
4284                 break;
4285             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4286                 event[14] = 1;
4287                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4288                 // 16,17 = 0, size 18
4289                 break;
4290             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4291                 event[14] = 1;
4292                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4293                 // for EIR packets, there is only one reponse in it
4294                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4295                 name = NULL;
4296                 // EIR data is 240 bytes in EIR event
4297                 for (ad_iterator_init(&context, 240, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4298                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4299                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4300                     const uint8_t * data = ad_iterator_get_data(&context);
4301                     // Prefer Complete Local Name over Shortend Local Name
4302                     switch (data_type){
4303                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4304                             if (name) continue;
4305                             /* fall through */
4306                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4307                             name = data;
4308                             name_len = data_size;
4309                             break;
4310                         default:
4311                             break;
4312                     }
4313                 }
4314                 if (name){
4315                     event[16] = 1;
4316                     // truncate name if needed
4317                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4318                     event[17] = len;
4319                     (void)memcpy(&event[18], name, len);
4320                     event_size += len;
4321                 }
4322                 break;
4323         }
4324         event[1] = event_size - 2;
4325         hci_emit_event(event, event_size, 1);
4326     }
4327 }
4328 #endif
4329 
4330 void hci_emit_state(void){
4331     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4332     uint8_t event[3];
4333     event[0] = BTSTACK_EVENT_STATE;
4334     event[1] = sizeof(event) - 2;
4335     event[2] = hci_stack->state;
4336     hci_emit_event(event, sizeof(event), 1);
4337 }
4338 
4339 #ifdef ENABLE_CLASSIC
4340 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4341     uint8_t event[13];
4342     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4343     event[1] = sizeof(event) - 2;
4344     event[2] = status;
4345     little_endian_store_16(event, 3, con_handle);
4346     reverse_bd_addr(address, &event[5]);
4347     event[11] = 1; // ACL connection
4348     event[12] = 0; // encryption disabled
4349     hci_emit_event(event, sizeof(event), 1);
4350 }
4351 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4352     if (disable_l2cap_timeouts) return;
4353     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4354     uint8_t event[4];
4355     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4356     event[1] = sizeof(event) - 2;
4357     little_endian_store_16(event, 2, conn->con_handle);
4358     hci_emit_event(event, sizeof(event), 1);
4359 }
4360 #endif
4361 
4362 #ifdef ENABLE_BLE
4363 #ifdef ENABLE_LE_CENTRAL
4364 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4365     uint8_t event[21];
4366     event[0] = HCI_EVENT_LE_META;
4367     event[1] = sizeof(event) - 2;
4368     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4369     event[3] = status;
4370     little_endian_store_16(event, 4, con_handle);
4371     event[6] = 0; // TODO: role
4372     event[7] = address_type;
4373     reverse_bd_addr(address, &event[8]);
4374     little_endian_store_16(event, 14, 0); // interval
4375     little_endian_store_16(event, 16, 0); // latency
4376     little_endian_store_16(event, 18, 0); // supervision timeout
4377     event[20] = 0; // master clock accuracy
4378     hci_emit_event(event, sizeof(event), 1);
4379 }
4380 #endif
4381 #endif
4382 
4383 static void hci_emit_transport_packet_sent(void){
4384     // notify upper stack that it might be possible to send again
4385     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4386     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4387 }
4388 
4389 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4390     uint8_t event[6];
4391     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4392     event[1] = sizeof(event) - 2;
4393     event[2] = 0; // status = OK
4394     little_endian_store_16(event, 3, con_handle);
4395     event[5] = reason;
4396     hci_emit_event(event, sizeof(event), 1);
4397 }
4398 
4399 static void hci_emit_nr_connections_changed(void){
4400     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4401     uint8_t event[3];
4402     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4403     event[1] = sizeof(event) - 2;
4404     event[2] = nr_hci_connections();
4405     hci_emit_event(event, sizeof(event), 1);
4406 }
4407 
4408 static void hci_emit_hci_open_failed(void){
4409     log_info("BTSTACK_EVENT_POWERON_FAILED");
4410     uint8_t event[2];
4411     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4412     event[1] = sizeof(event) - 2;
4413     hci_emit_event(event, sizeof(event), 1);
4414 }
4415 
4416 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4417     log_info("hci_emit_dedicated_bonding_result %u ", status);
4418     uint8_t event[9];
4419     int pos = 0;
4420     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4421     event[pos++] = sizeof(event) - 2;
4422     event[pos++] = status;
4423     reverse_bd_addr(address, &event[pos]);
4424     hci_emit_event(event, sizeof(event), 1);
4425 }
4426 
4427 
4428 #ifdef ENABLE_CLASSIC
4429 
4430 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4431     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4432     uint8_t event[5];
4433     int pos = 0;
4434     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4435     event[pos++] = sizeof(event) - 2;
4436     little_endian_store_16(event, 2, con_handle);
4437     pos += 2;
4438     event[pos++] = level;
4439     hci_emit_event(event, sizeof(event), 1);
4440 }
4441 
4442 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4443     if (!connection) return LEVEL_0;
4444     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4445     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4446     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4447     // LEVEL 4 always requires 128 bit encrytion key size
4448     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4449         security_level = LEVEL_3;
4450     }
4451     return security_level;
4452 }
4453 
4454 static void hci_emit_discoverable_enabled(uint8_t enabled){
4455     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4456     uint8_t event[3];
4457     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4458     event[1] = sizeof(event) - 2;
4459     event[2] = enabled;
4460     hci_emit_event(event, sizeof(event), 1);
4461 }
4462 
4463 // query if remote side supports eSCO
4464 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4465     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4466     if (!connection) return 0;
4467     return connection->remote_supported_feature_eSCO;
4468 }
4469 
4470 // query if remote side supports SSP
4471 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4472     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4473     if (!connection) return 0;
4474     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
4475 }
4476 
4477 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4478     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4479 }
4480 
4481 // GAP API
4482 /**
4483  * @bbrief enable/disable bonding. default is enabled
4484  * @praram enabled
4485  */
4486 void gap_set_bondable_mode(int enable){
4487     hci_stack->bondable = enable ? 1 : 0;
4488 }
4489 /**
4490  * @brief Get bondable mode.
4491  * @return 1 if bondable
4492  */
4493 int gap_get_bondable_mode(void){
4494     return hci_stack->bondable;
4495 }
4496 
4497 /**
4498  * @brief map link keys to security levels
4499  */
4500 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4501     switch (link_key_type){
4502         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4503             return LEVEL_4;
4504         case COMBINATION_KEY:
4505         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4506             return LEVEL_3;
4507         default:
4508             return LEVEL_2;
4509     }
4510 }
4511 
4512 /**
4513  * @brief map link keys to secure connection yes/no
4514  */
4515 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4516     switch (link_key_type){
4517         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4518         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4519             return 1;
4520         default:
4521             return 0;
4522     }
4523 }
4524 
4525 /**
4526  * @brief map link keys to authenticated
4527  */
4528 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4529     switch (link_key_type){
4530         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4531         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4532             return 1;
4533         default:
4534             return 0;
4535     }
4536 }
4537 
4538 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4539     log_info("gap_mitm_protection_required_for_security_level %u", level);
4540     return level > LEVEL_2;
4541 }
4542 
4543 /**
4544  * @brief get current security level
4545  */
4546 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4547     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4548     if (!connection) return LEVEL_0;
4549     return gap_security_level_for_connection(connection);
4550 }
4551 
4552 /**
4553  * @brief request connection to device to
4554  * @result GAP_AUTHENTICATION_RESULT
4555  */
4556 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4557     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4558     if (!connection){
4559         hci_emit_security_level(con_handle, LEVEL_0);
4560         return;
4561     }
4562     gap_security_level_t current_level = gap_security_level(con_handle);
4563     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4564         requested_level, connection->requested_security_level, current_level);
4565 
4566     // assumption: earlier requested security higher than current level => security request is active
4567     if (current_level < connection->requested_security_level){
4568         if (connection->requested_security_level < requested_level){
4569             // increase requested level as new level is higher
4570 
4571             // TODO: handle re-authentication when done
4572 
4573             connection->requested_security_level = requested_level;
4574         }
4575         return;
4576     }
4577 
4578     // no request active, notify if security sufficient
4579     if (requested_level <= current_level){
4580         hci_emit_security_level(con_handle, current_level);
4581         return;
4582     }
4583 
4584     // start pairing to increase security level
4585     connection->requested_security_level = requested_level;
4586 
4587 #if 0
4588     // sending encryption request without a link key results in an error.
4589     // TODO: figure out how to use it properly
4590 
4591     // would enabling ecnryption suffice (>= LEVEL_2)?
4592     if (hci_stack->link_key_db){
4593         link_key_type_t link_key_type;
4594         link_key_t      link_key;
4595         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4596             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4597                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4598                 return;
4599             }
4600         }
4601     }
4602 #endif
4603 
4604     // start to authenticate connection
4605     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4606     hci_run();
4607 }
4608 
4609 /**
4610  * @brief start dedicated bonding with device. disconnect after bonding
4611  * @param device
4612  * @param request MITM protection
4613  * @result GAP_DEDICATED_BONDING_COMPLETE
4614  */
4615 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4616 
4617     // create connection state machine
4618     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4619 
4620     if (!connection){
4621         return BTSTACK_MEMORY_ALLOC_FAILED;
4622     }
4623 
4624     // delete linkn key
4625     gap_drop_link_key_for_bd_addr(device);
4626 
4627     // configure LEVEL_2/3, dedicated bonding
4628     connection->state = SEND_CREATE_CONNECTION;
4629     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4630     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4631     connection->bonding_flags = BONDING_DEDICATED;
4632 
4633     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4634 
4635     // handle: connnection failure (connection complete != ok)
4636     // handle: authentication failure
4637     // handle: disconnect on done
4638 
4639     hci_run();
4640 
4641     return 0;
4642 }
4643 #endif
4644 
4645 void gap_set_local_name(const char * local_name){
4646     hci_stack->local_name = local_name;
4647 }
4648 
4649 
4650 #ifdef ENABLE_BLE
4651 
4652 #ifdef ENABLE_LE_CENTRAL
4653 void gap_start_scan(void){
4654     hci_stack->le_scanning_enabled = 1;
4655     hci_run();
4656 }
4657 
4658 void gap_stop_scan(void){
4659     hci_stack->le_scanning_enabled = 0;
4660     hci_run();
4661 }
4662 
4663 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4664     hci_stack->le_scan_type     = scan_type;
4665     hci_stack->le_scan_interval = scan_interval;
4666     hci_stack->le_scan_window   = scan_window;
4667     hci_run();
4668 }
4669 
4670 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4671     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4672     if (!conn){
4673         log_info("gap_connect: no connection exists yet, creating context");
4674         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4675         if (!conn){
4676             // notify client that alloc failed
4677             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4678             log_info("gap_connect: failed to alloc hci_connection_t");
4679             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4680         }
4681         conn->state = SEND_CREATE_CONNECTION;
4682         log_info("gap_connect: send create connection next");
4683         hci_run();
4684         return 0;
4685     }
4686 
4687     if (!hci_is_le_connection(conn) ||
4688         (conn->state == SEND_CREATE_CONNECTION) ||
4689         (conn->state == SENT_CREATE_CONNECTION)) {
4690         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4691         log_error("gap_connect: classic connection or connect is already being created");
4692         return GATT_CLIENT_IN_WRONG_STATE;
4693     }
4694 
4695     log_info("gap_connect: context exists with state %u", conn->state);
4696     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4697     hci_run();
4698     return 0;
4699 }
4700 
4701 // @assumption: only a single outgoing LE Connection exists
4702 static hci_connection_t * gap_get_outgoing_connection(void){
4703     btstack_linked_item_t *it;
4704     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4705         hci_connection_t * conn = (hci_connection_t *) it;
4706         if (!hci_is_le_connection(conn)) continue;
4707         switch (conn->state){
4708             case SEND_CREATE_CONNECTION:
4709             case SENT_CREATE_CONNECTION:
4710             case SENT_CANCEL_CONNECTION:
4711                 return conn;
4712             default:
4713                 break;
4714         };
4715     }
4716     return NULL;
4717 }
4718 
4719 uint8_t gap_connect_cancel(void){
4720     hci_connection_t * conn = gap_get_outgoing_connection();
4721     if (!conn) return 0;
4722     switch (conn->state){
4723         case SEND_CREATE_CONNECTION:
4724             // skip sending create connection and emit event instead
4725             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4726             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4727             btstack_memory_hci_connection_free( conn );
4728             break;
4729         case SENT_CREATE_CONNECTION:
4730             // request to send cancel connection
4731             conn->state = SEND_CANCEL_CONNECTION;
4732             hci_run();
4733             break;
4734         default:
4735             break;
4736     }
4737     return 0;
4738 }
4739 #endif
4740 
4741 #ifdef ENABLE_LE_CENTRAL
4742 /**
4743  * @brief Set connection parameters for outgoing connections
4744  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4745  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4746  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4747  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4748  * @param conn_latency, default: 4
4749  * @param supervision_timeout (unit: 10ms), default: 720 ms
4750  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4751  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4752  */
4753 
4754 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4755     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4756     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4757     hci_stack->le_connection_scan_interval = conn_scan_interval;
4758     hci_stack->le_connection_scan_window = conn_scan_window;
4759     hci_stack->le_connection_interval_min = conn_interval_min;
4760     hci_stack->le_connection_interval_max = conn_interval_max;
4761     hci_stack->le_connection_latency = conn_latency;
4762     hci_stack->le_supervision_timeout = supervision_timeout;
4763     hci_stack->le_minimum_ce_length = min_ce_length;
4764     hci_stack->le_maximum_ce_length = max_ce_length;
4765 }
4766 #endif
4767 
4768 /**
4769  * @brief Updates the connection parameters for a given LE connection
4770  * @param handle
4771  * @param conn_interval_min (unit: 1.25ms)
4772  * @param conn_interval_max (unit: 1.25ms)
4773  * @param conn_latency
4774  * @param supervision_timeout (unit: 10ms)
4775  * @returns 0 if ok
4776  */
4777 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4778     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4779     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4780     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4781     connection->le_conn_interval_min = conn_interval_min;
4782     connection->le_conn_interval_max = conn_interval_max;
4783     connection->le_conn_latency = conn_latency;
4784     connection->le_supervision_timeout = supervision_timeout;
4785     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4786     hci_run();
4787     return 0;
4788 }
4789 
4790 /**
4791  * @brief Request an update of the connection parameter for a given LE connection
4792  * @param handle
4793  * @param conn_interval_min (unit: 1.25ms)
4794  * @param conn_interval_max (unit: 1.25ms)
4795  * @param conn_latency
4796  * @param supervision_timeout (unit: 10ms)
4797  * @returns 0 if ok
4798  */
4799 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4800     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4801     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4802     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4803     connection->le_conn_interval_min = conn_interval_min;
4804     connection->le_conn_interval_max = conn_interval_max;
4805     connection->le_conn_latency = conn_latency;
4806     connection->le_supervision_timeout = supervision_timeout;
4807     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4808     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4809     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4810     return 0;
4811 }
4812 
4813 #ifdef ENABLE_LE_PERIPHERAL
4814 
4815 static void gap_advertisments_changed(void){
4816     // disable advertisements before updating adv, scan data, or adv params
4817     if (hci_stack->le_advertisements_active){
4818         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4819     }
4820     hci_run();
4821 }
4822 
4823 /**
4824  * @brief Set Advertisement Data
4825  * @param advertising_data_length
4826  * @param advertising_data (max 31 octets)
4827  * @note data is not copied, pointer has to stay valid
4828  */
4829 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4830     hci_stack->le_advertisements_data_len = advertising_data_length;
4831     hci_stack->le_advertisements_data = advertising_data;
4832     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4833     gap_advertisments_changed();
4834 }
4835 
4836 /**
4837  * @brief Set Scan Response Data
4838  * @param advertising_data_length
4839  * @param advertising_data (max 31 octets)
4840  * @note data is not copied, pointer has to stay valid
4841  */
4842 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4843     hci_stack->le_scan_response_data_len = scan_response_data_length;
4844     hci_stack->le_scan_response_data = scan_response_data;
4845     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4846     gap_advertisments_changed();
4847 }
4848 
4849 /**
4850  * @brief Set Advertisement Parameters
4851  * @param adv_int_min
4852  * @param adv_int_max
4853  * @param adv_type
4854  * @param direct_address_type
4855  * @param direct_address
4856  * @param channel_map
4857  * @param filter_policy
4858  *
4859  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4860  */
4861  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4862     uint8_t direct_address_typ, bd_addr_t direct_address,
4863     uint8_t channel_map, uint8_t filter_policy) {
4864 
4865     hci_stack->le_advertisements_interval_min = adv_int_min;
4866     hci_stack->le_advertisements_interval_max = adv_int_max;
4867     hci_stack->le_advertisements_type = adv_type;
4868     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4869     hci_stack->le_advertisements_channel_map = channel_map;
4870     hci_stack->le_advertisements_filter_policy = filter_policy;
4871     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
4872                  6);
4873 
4874     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4875     gap_advertisments_changed();
4876  }
4877 
4878 /**
4879  * @brief Enable/Disable Advertisements
4880  * @param enabled
4881  */
4882 void gap_advertisements_enable(int enabled){
4883     hci_stack->le_advertisements_enabled = enabled;
4884     if (enabled && !hci_stack->le_advertisements_active){
4885         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
4886     }
4887     if (!enabled && hci_stack->le_advertisements_active){
4888         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
4889     }
4890     hci_run();
4891 }
4892 
4893 #endif
4894 
4895 void hci_le_set_own_address_type(uint8_t own_address_type){
4896     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
4897     if (own_address_type == hci_stack->le_own_addr_type) return;
4898     hci_stack->le_own_addr_type = own_address_type;
4899 
4900 #ifdef ENABLE_LE_PERIPHERAL
4901     // update advertisement parameters, too
4902     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4903     gap_advertisments_changed();
4904 #endif
4905 #ifdef ENABLE_LE_CENTRAL
4906     // note: we don't update scan parameters or modify ongoing connection attempts
4907 #endif
4908 }
4909 
4910 #endif
4911 
4912 uint8_t gap_disconnect(hci_con_handle_t handle){
4913     hci_connection_t * conn = hci_connection_for_handle(handle);
4914     if (!conn){
4915         hci_emit_disconnection_complete(handle, 0);
4916         return 0;
4917     }
4918     // ignore if already disconnected
4919     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4920         return 0;
4921     }
4922     conn->state = SEND_DISCONNECT;
4923     hci_run();
4924     return 0;
4925 }
4926 
4927 int gap_read_rssi(hci_con_handle_t con_handle){
4928     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
4929     if (hci_connection == NULL) return 0;
4930     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
4931     hci_run();
4932     return 1;
4933 }
4934 
4935 /**
4936  * @brief Get connection type
4937  * @param con_handle
4938  * @result connection_type
4939  */
4940 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
4941     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4942     if (!conn) return GAP_CONNECTION_INVALID;
4943     switch (conn->address_type){
4944         case BD_ADDR_TYPE_LE_PUBLIC:
4945         case BD_ADDR_TYPE_LE_RANDOM:
4946             return GAP_CONNECTION_LE;
4947         case BD_ADDR_TYPE_SCO:
4948             return GAP_CONNECTION_SCO;
4949         case BD_ADDR_TYPE_ACL:
4950             return GAP_CONNECTION_ACL;
4951         default:
4952             return GAP_CONNECTION_INVALID;
4953     }
4954 }
4955 
4956 #ifdef ENABLE_BLE
4957 
4958 uint8_t gap_le_set_phy(hci_con_handle_t connection_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
4959     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
4960     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4961 
4962     conn->le_phy_update_all_phys    = all_phys;
4963     conn->le_phy_update_tx_phys     = tx_phys;
4964     conn->le_phy_update_rx_phys     = rx_phys;
4965     conn->le_phy_update_phy_options = phy_options;
4966 
4967     hci_run();
4968 
4969     return 0;
4970 }
4971 
4972 #ifdef ENABLE_LE_CENTRAL
4973 /**
4974  * @brief Auto Connection Establishment - Start Connecting to device
4975  * @param address_typ
4976  * @param address
4977  * @returns 0 if ok
4978  */
4979 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
4980     // check capacity
4981     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
4982     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
4983     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
4984     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
4985     entry->address_type = address_type;
4986     (void)memcpy(entry->address, address, 6);
4987     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
4988     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
4989     hci_run();
4990     return 0;
4991 }
4992 
4993 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
4994     btstack_linked_list_iterator_t it;
4995     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
4996     while (btstack_linked_list_iterator_has_next(&it)){
4997         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
4998         if (entry->address_type != address_type) continue;
4999         if (memcmp(entry->address, address, 6) != 0) continue;
5000         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5001             // remove from controller if already present
5002             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5003             continue;
5004         }
5005         // direclty remove entry from whitelist
5006         btstack_linked_list_iterator_remove(&it);
5007         btstack_memory_whitelist_entry_free(entry);
5008     }
5009 }
5010 
5011 /**
5012  * @brief Auto Connection Establishment - Stop Connecting to device
5013  * @param address_typ
5014  * @param address
5015  * @returns 0 if ok
5016  */
5017 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5018     hci_remove_from_whitelist(address_type, address);
5019     hci_run();
5020     return 0;
5021 }
5022 
5023 /**
5024  * @brief Auto Connection Establishment - Stop everything
5025  * @note  Convenience function to stop all active auto connection attempts
5026  */
5027 void gap_auto_connection_stop_all(void){
5028     btstack_linked_list_iterator_t it;
5029     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5030     while (btstack_linked_list_iterator_has_next(&it)){
5031         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5032         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5033             // remove from controller if already present
5034             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5035             continue;
5036         }
5037         // directly remove entry from whitelist
5038         btstack_linked_list_iterator_remove(&it);
5039         btstack_memory_whitelist_entry_free(entry);
5040     }
5041     hci_run();
5042 }
5043 
5044 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5045     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5046     if (!conn) return 0;
5047     return conn->le_connection_interval;
5048 }
5049 #endif
5050 #endif
5051 
5052 #ifdef ENABLE_CLASSIC
5053 /**
5054  * @brief Set Extended Inquiry Response data
5055  * @param eir_data size 240 bytes, is not copied make sure memory is accessible during stack startup
5056  * @note has to be done before stack starts up
5057  */
5058 void gap_set_extended_inquiry_response(const uint8_t * data){
5059     hci_stack->eir_data = data;
5060 }
5061 
5062 /**
5063  * @brief Start GAP Classic Inquiry
5064  * @param duration in 1.28s units
5065  * @return 0 if ok
5066  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5067  */
5068 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5069     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5070     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5071     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5072         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5073     }
5074     hci_stack->inquiry_state = duration_in_1280ms_units;
5075     hci_run();
5076     return 0;
5077 }
5078 
5079 /**
5080  * @brief Stop GAP Classic Inquiry
5081  * @returns 0 if ok
5082  */
5083 int gap_inquiry_stop(void){
5084     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5085         // emit inquiry complete event, before it even started
5086         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5087         hci_emit_event(event, sizeof(event), 1);
5088         return 0;
5089     }
5090     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5091     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5092     hci_run();
5093     return 0;
5094 }
5095 
5096 
5097 /**
5098  * @brief Remote Name Request
5099  * @param addr
5100  * @param page_scan_repetition_mode
5101  * @param clock_offset only used when bit 15 is set
5102  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5103  */
5104 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5105     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5106     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5107     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5108     hci_stack->remote_name_clock_offset = clock_offset;
5109     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5110     hci_run();
5111     return 0;
5112 }
5113 
5114 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5115     hci_stack->gap_pairing_state = state;
5116     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5117     hci_run();
5118     return 0;
5119 }
5120 
5121 /**
5122  * @brief Legacy Pairing Pin Code Response
5123  * @param addr
5124  * @param pin
5125  * @return 0 if ok
5126  */
5127 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5128     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5129     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5130     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5131 }
5132 
5133 /**
5134  * @brief Abort Legacy Pairing
5135  * @param addr
5136  * @param pin
5137  * @return 0 if ok
5138  */
5139 int gap_pin_code_negative(bd_addr_t addr){
5140     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5141     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5142 }
5143 
5144 /**
5145  * @brief SSP Passkey Response
5146  * @param addr
5147  * @param passkey
5148  * @return 0 if ok
5149  */
5150 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5151     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5152     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5153     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5154 }
5155 
5156 /**
5157  * @brief Abort SSP Passkey Entry/Pairing
5158  * @param addr
5159  * @param pin
5160  * @return 0 if ok
5161  */
5162 int gap_ssp_passkey_negative(bd_addr_t addr){
5163     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5164     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5165 }
5166 
5167 /**
5168  * @brief Accept SSP Numeric Comparison
5169  * @param addr
5170  * @param passkey
5171  * @return 0 if ok
5172  */
5173 int gap_ssp_confirmation_response(bd_addr_t addr){
5174     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5175     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5176 }
5177 
5178 /**
5179  * @brief Abort SSP Numeric Comparison/Pairing
5180  * @param addr
5181  * @param pin
5182  * @return 0 if ok
5183  */
5184 int gap_ssp_confirmation_negative(bd_addr_t addr){
5185     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5186     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5187 }
5188 
5189 /**
5190  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5191  * @param inquiry_mode see bluetooth_defines.h
5192  */
5193 void hci_set_inquiry_mode(inquiry_mode_t mode){
5194     hci_stack->inquiry_mode = mode;
5195 }
5196 
5197 /**
5198  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5199  */
5200 void hci_set_sco_voice_setting(uint16_t voice_setting){
5201     hci_stack->sco_voice_setting = voice_setting;
5202 }
5203 
5204 /**
5205  * @brief Get SCO Voice Setting
5206  * @return current voice setting
5207  */
5208 uint16_t hci_get_sco_voice_setting(void){
5209     return hci_stack->sco_voice_setting;
5210 }
5211 
5212 static int hci_have_usb_transport(void){
5213     if (!hci_stack->hci_transport) return 0;
5214     const char * transport_name = hci_stack->hci_transport->name;
5215     if (!transport_name) return 0;
5216     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5217 }
5218 
5219 /** @brief Get SCO packet length for current SCO Voice setting
5220  *  @note  Using SCO packets of the exact length is required for USB transfer
5221  *  @return Length of SCO packets in bytes (not audio frames)
5222  */
5223 int hci_get_sco_packet_length(void){
5224     int sco_packet_length = 0;
5225 
5226 #ifdef ENABLE_SCO_OVER_HCI
5227 
5228     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5229     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5230 
5231     if (hci_have_usb_transport()){
5232         // see Core Spec for H2 USB Transfer.
5233         // 3 byte SCO header + 24 bytes per connection
5234         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5235         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5236     } else {
5237         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5238         sco_packet_length = 3 + 60 * multiplier;
5239         // assert that it still fits inside an SCO buffer
5240         if (sco_packet_length > hci_stack->sco_data_packet_length){
5241             sco_packet_length = 3 + 60;
5242         }
5243     }
5244 #endif
5245     return sco_packet_length;
5246 }
5247 
5248 /**
5249 * @brief Sets the master/slave policy
5250 * @param policy (0: attempt to become master, 1: let connecting device decide)
5251 */
5252 void hci_set_master_slave_policy(uint8_t policy){
5253     hci_stack->master_slave_policy = policy;
5254 }
5255 
5256 #endif
5257 
5258 HCI_STATE hci_get_state(void){
5259     return hci_stack->state;
5260 }
5261 
5262 #ifdef ENABLE_CLASSIC
5263 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5264     hci_stack->gap_classic_accept_callback = accept_callback;
5265 }
5266 #endif
5267 
5268 /**
5269  * @brief Set callback for Bluetooth Hardware Error
5270  */
5271 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5272     hci_stack->hardware_error_callback = fn;
5273 }
5274 
5275 void hci_disconnect_all(void){
5276     btstack_linked_list_iterator_t it;
5277     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5278     while (btstack_linked_list_iterator_has_next(&it)){
5279         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5280         if (con->state == SENT_DISCONNECT) continue;
5281         con->state = SEND_DISCONNECT;
5282     }
5283     hci_run();
5284 }
5285 
5286 uint16_t hci_get_manufacturer(void){
5287     return hci_stack->manufacturer;
5288 }
5289 
5290 #ifdef ENABLE_BLE
5291 
5292 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5293     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5294     if (!hci_con) return NULL;
5295     return &hci_con->sm_connection;
5296 }
5297 
5298 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5299 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5300 
5301 int gap_encryption_key_size(hci_con_handle_t con_handle){
5302     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5303     if (hci_connection == NULL) return 0;
5304     if (hci_is_le_connection(hci_connection)){
5305         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5306         if (sm_conn->sm_connection_encrypted) {
5307             return sm_conn->sm_actual_encryption_key_size;
5308         }
5309     }
5310 #ifdef ENABLE_CLASSIC
5311     else {
5312         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5313             return hci_connection->encryption_key_size;
5314         }
5315     }
5316 #endif
5317     return 0;
5318 }
5319 
5320 int gap_authenticated(hci_con_handle_t con_handle){
5321     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5322     if (hci_connection == NULL) return 0;
5323 
5324     switch (hci_connection->address_type){
5325         case BD_ADDR_TYPE_LE_PUBLIC:
5326         case BD_ADDR_TYPE_LE_RANDOM:
5327             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5328             return hci_connection->sm_connection.sm_connection_authenticated;
5329 #ifdef ENABLE_CLASSIC
5330         case BD_ADDR_TYPE_SCO:
5331         case BD_ADDR_TYPE_ACL:
5332             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5333 #endif
5334         default:
5335             return 0;
5336     }
5337 }
5338 
5339 int gap_secure_connection(hci_con_handle_t con_handle){
5340     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5341     if (hci_connection == NULL) return 0;
5342 
5343     switch (hci_connection->address_type){
5344         case BD_ADDR_TYPE_LE_PUBLIC:
5345         case BD_ADDR_TYPE_LE_RANDOM:
5346             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5347             return hci_connection->sm_connection.sm_connection_sc;
5348 #ifdef ENABLE_CLASSIC
5349         case BD_ADDR_TYPE_SCO:
5350         case BD_ADDR_TYPE_ACL:
5351             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5352 #endif
5353         default:
5354             return 0;
5355     }
5356 }
5357 
5358 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5359     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5360     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5361     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5362     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5363     return sm_conn->sm_connection_authorization_state;
5364 }
5365 #endif
5366 
5367 #ifdef ENABLE_CLASSIC
5368 uint8_t gap_sniff_mode_enter(hci_con_handle_t con_handle, uint16_t sniff_min_interval, uint16_t sniff_max_interval, uint16_t sniff_attempt, uint16_t sniff_timeout){
5369     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5370     if (!conn) return GAP_CONNECTION_INVALID;
5371     conn->sniff_min_interval = sniff_min_interval;
5372     conn->sniff_max_interval = sniff_max_interval;
5373     conn->sniff_attempt = sniff_attempt;
5374     conn->sniff_timeout = sniff_timeout;
5375     hci_run();
5376     return 0;
5377 }
5378 
5379 /**
5380  * @brief Exit Sniff mode
5381  * @param con_handle
5382  @ @return 0 if ok
5383  */
5384 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5385     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5386     if (!conn) return GAP_CONNECTION_INVALID;
5387     conn->sniff_min_interval = 0xffff;
5388     hci_run();
5389     return 0;
5390 }
5391 #endif
5392 
5393 void hci_halting_defer(void){
5394     if (hci_stack->state != HCI_STATE_HALTING) return;
5395     switch (hci_stack->substate){
5396         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5397         case HCI_HALTING_CLOSE:
5398             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5399             break;
5400         default:
5401             break;
5402     }
5403 }
5404 
5405 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5406 void hci_setup_test_connections_fuzz(void){
5407     hci_connection_t * conn;
5408 
5409     // default address: 66:55:44:33:00:01
5410     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5411 
5412     // setup Controller info
5413     hci_stack->num_cmd_packets = 255;
5414     hci_stack->acl_packets_total_num = 255;
5415 
5416     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5417     addr[5] = 0x01;
5418     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5419     conn->con_handle = addr[5];
5420     conn->role  = HCI_ROLE_SLAVE;
5421     conn->state = RECEIVED_CONNECTION_REQUEST;
5422     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5423 
5424     // setup incoming Classic SCO connection with con handle 0x0002
5425     addr[5] = 0x02;
5426     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5427     conn->con_handle = addr[5];
5428     conn->role  = HCI_ROLE_SLAVE;
5429     conn->state = RECEIVED_CONNECTION_REQUEST;
5430     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5431 
5432     // setup ready Classic ACL connection with con handle 0x0003
5433     addr[5] = 0x03;
5434     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5435     conn->con_handle = addr[5];
5436     conn->role  = HCI_ROLE_SLAVE;
5437     conn->state = OPEN;
5438     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5439 
5440     // setup ready Classic SCO connection with con handle 0x0004
5441     addr[5] = 0x04;
5442     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5443     conn->con_handle = addr[5];
5444     conn->role  = HCI_ROLE_SLAVE;
5445     conn->state = OPEN;
5446     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5447 
5448     // setup ready LE ACL connection with con handle 0x005 and public address
5449     addr[5] = 0x05;
5450     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5451     conn->con_handle = addr[5];
5452     conn->role  = HCI_ROLE_SLAVE;
5453     conn->state = OPEN;
5454     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5455 }
5456 
5457 void hci_free_connections_fuzz(void){
5458     btstack_linked_list_iterator_t it;
5459     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5460     while (btstack_linked_list_iterator_has_next(&it)){
5461         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5462         btstack_linked_list_iterator_remove(&it);
5463         btstack_memory_hci_connection_free(con);
5464     }
5465 }
5466 void hci_simulate_working_fuzz(void){
5467     hci_init_done();
5468     hci_stack->num_cmd_packets = 255;
5469 }
5470 #endif
5471