xref: /btstack/src/hci.c (revision 2f5c44ba2e293d61761ff0716c843ff9512a4bf7)
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 bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->address_type = addr_type;
199     conn->con_handle = 0xffff;
200     conn->authentication_flags = AUTH_FLAGS_NONE;
201     conn->bonding_flags = 0;
202     conn->requested_security_level = LEVEL_0;
203 #ifdef ENABLE_CLASSIC
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
220     return conn;
221 }
222 
223 
224 /**
225  * get le connection parameter range
226 *
227  * @return le connection parameter range struct
228  */
229 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
230     *range = hci_stack->le_connection_parameter_range;
231 }
232 
233 /**
234  * set le connection parameter range
235  *
236  */
237 
238 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
239     hci_stack->le_connection_parameter_range = *range;
240 }
241 
242 /**
243  * @brief Test if connection parameters are inside in existing rage
244  * @param conn_interval_min (unit: 1.25ms)
245  * @param conn_interval_max (unit: 1.25ms)
246  * @param conn_latency
247  * @param supervision_timeout (unit: 10ms)
248  * @returns 1 if included
249  */
250 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){
251     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
252     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
253 
254     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
255     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
256 
257     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
258     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
259 
260     return 1;
261 }
262 
263 /**
264  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
265  * @note: default: 1
266  * @param max_peripheral_connections
267  */
268 #ifdef ENABLE_LE_PERIPHERAL
269 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
270     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
271 }
272 #endif
273 
274 /**
275  * get hci connections iterator
276  *
277  * @return hci connections iterator
278  */
279 
280 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
281     btstack_linked_list_iterator_init(it, &hci_stack->connections);
282 }
283 
284 /**
285  * get connection for a given handle
286  *
287  * @return connection OR NULL, if not found
288  */
289 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
290     btstack_linked_list_iterator_t it;
291     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
292     while (btstack_linked_list_iterator_has_next(&it)){
293         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
294         if ( item->con_handle == con_handle ) {
295             return item;
296         }
297     }
298     return NULL;
299 }
300 
301 /**
302  * get connection for given address
303  *
304  * @return connection OR NULL, if not found
305  */
306 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
307     btstack_linked_list_iterator_t it;
308     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
309     while (btstack_linked_list_iterator_has_next(&it)){
310         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
311         if (connection->address_type != addr_type)  continue;
312         if (memcmp(addr, connection->address, 6) != 0) continue;
313         return connection;
314     }
315     return NULL;
316 }
317 
318 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
319     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
320 }
321 
322 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
323     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
324 }
325 
326 #ifdef ENABLE_CLASSIC
327 
328 #ifdef ENABLE_SCO_OVER_HCI
329 static int hci_number_sco_connections(void){
330     int connections = 0;
331     btstack_linked_list_iterator_t it;
332     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
333     while (btstack_linked_list_iterator_has_next(&it)){
334         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
335         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
336         connections++;
337     }
338     return connections;
339 }
340 #endif
341 
342 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
343     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
344 #ifdef HAVE_EMBEDDED_TICK
345     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
346         // connections might be timed out
347         hci_emit_l2cap_check_timeout(connection);
348     }
349 #else
350     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
351         // connections might be timed out
352         hci_emit_l2cap_check_timeout(connection);
353     }
354 #endif
355 }
356 
357 static void hci_connection_timestamp(hci_connection_t *connection){
358 #ifdef HAVE_EMBEDDED_TICK
359     connection->timestamp = btstack_run_loop_embedded_get_ticks();
360 #else
361     connection->timestamp = btstack_run_loop_get_time_ms();
362 #endif
363 }
364 
365 /**
366  * add authentication flags and reset timer
367  * @note: assumes classic connection
368  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
369  */
370 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
371     bd_addr_t addr;
372     reverse_bd_addr(bd_addr, addr);
373     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
374     if (conn) {
375         connectionSetAuthenticationFlags(conn, flags);
376         hci_connection_timestamp(conn);
377     }
378 }
379 
380 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
381     hci_connection_t * conn = hci_connection_for_handle(handle);
382     if (!conn) return 0;
383     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
384     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
385     return 0;
386 }
387 
388 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
389     if (!hci_stack->link_key_db) return;
390     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
391     hci_stack->link_key_db->delete_link_key(addr);
392 }
393 
394 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
395     if (!hci_stack->link_key_db) return;
396     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
397     hci_stack->link_key_db->put_link_key(addr, link_key, type);
398 }
399 
400 void gap_delete_all_link_keys(void){
401     bd_addr_t  addr;
402     link_key_t link_key;
403     link_key_type_t type;
404     btstack_link_key_iterator_t it;
405     int ok = gap_link_key_iterator_init(&it);
406     if (!ok) {
407         log_error("could not initialize iterator");
408         return;
409     }
410     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
411         gap_drop_link_key_for_bd_addr(addr);
412     }
413     gap_link_key_iterator_done(&it);
414 }
415 
416 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
417     if (!hci_stack->link_key_db) return 0;
418     if (!hci_stack->link_key_db->iterator_init) return 0;
419     return hci_stack->link_key_db->iterator_init(it);
420 }
421 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){
422     if (!hci_stack->link_key_db) return 0;
423     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
424 }
425 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
426     if (!hci_stack->link_key_db) return;
427     hci_stack->link_key_db->iterator_done(it);
428 }
429 #endif
430 
431 static int hci_is_le_connection(hci_connection_t * connection){
432     switch (connection->address_type){
433         case BD_ADDR_TYPE_LE_PUBLIC:
434         case BD_ADDR_TYPE_LE_RANDOM:
435         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
436         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
437             return 1;
438         default:
439             return 0;
440     }
441 }
442 
443 /**
444  * count connections
445  */
446 static int nr_hci_connections(void){
447     int count = 0;
448     btstack_linked_item_t *it;
449     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
450         count++;
451     }
452     return count;
453 }
454 
455 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
456 
457     unsigned int num_packets_sent_classic = 0;
458     unsigned int num_packets_sent_le = 0;
459 
460     btstack_linked_item_t *it;
461     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
462         hci_connection_t * connection = (hci_connection_t *) it;
463         if (hci_is_le_connection(connection)){
464             num_packets_sent_le += connection->num_packets_sent;
465         }
466         if (connection->address_type == BD_ADDR_TYPE_ACL){
467             num_packets_sent_classic += connection->num_packets_sent;
468         }
469     }
470     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
471     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
472     int free_slots_le = 0;
473 
474     if (free_slots_classic < 0){
475         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);
476         return 0;
477     }
478 
479     if (hci_stack->le_acl_packets_total_num){
480         // if we have LE slots, they are used
481         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
482         if (free_slots_le < 0){
483             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);
484             return 0;
485         }
486     } else {
487         // otherwise, classic slots are used for LE, too
488         free_slots_classic -= num_packets_sent_le;
489         if (free_slots_classic < 0){
490             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);
491             return 0;
492         }
493     }
494 
495     switch (address_type){
496         case BD_ADDR_TYPE_UNKNOWN:
497             log_error("hci_number_free_acl_slots: unknown address type");
498             return 0;
499 
500         case BD_ADDR_TYPE_ACL:
501             return free_slots_classic;
502 
503         default:
504            if (hci_stack->le_acl_packets_total_num){
505                return free_slots_le;
506            }
507            return free_slots_classic;
508     }
509 }
510 
511 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
512     // get connection type
513     hci_connection_t * connection = hci_connection_for_handle(con_handle);
514     if (!connection){
515         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
516         return 0;
517     }
518     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
519 }
520 
521 #ifdef ENABLE_CLASSIC
522 static int hci_number_free_sco_slots(void){
523     unsigned int num_sco_packets_sent  = 0;
524     btstack_linked_item_t *it;
525     if (hci_stack->synchronous_flow_control_enabled){
526         // explicit flow control
527         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
528             hci_connection_t * connection = (hci_connection_t *) it;
529             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
530             num_sco_packets_sent += connection->num_packets_sent;
531         }
532         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
533             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
534             return 0;
535         }
536         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
537     } else {
538         // implicit flow control -- TODO
539         int num_ready = 0;
540         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
541             hci_connection_t * connection = (hci_connection_t *) it;
542             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
543             if (connection->sco_tx_ready == 0) continue;
544             num_ready++;
545         }
546         return num_ready;
547     }
548 }
549 #endif
550 
551 // only used to send HCI Host Number Completed Packets
552 static int hci_can_send_comand_packet_transport(void){
553     if (hci_stack->hci_packet_buffer_reserved) return 0;
554 
555     // check for async hci transport implementations
556     if (hci_stack->hci_transport->can_send_packet_now){
557         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
558             return 0;
559         }
560     }
561     return 1;
562 }
563 
564 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
565 int hci_can_send_command_packet_now(void){
566     if (hci_can_send_comand_packet_transport() == 0) return 0;
567     return hci_stack->num_cmd_packets > 0;
568 }
569 
570 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
571     // check for async hci transport implementations
572     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
573     return hci_stack->hci_transport->can_send_packet_now(packet_type);
574 }
575 
576 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
577     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
578     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
579 }
580 
581 int hci_can_send_acl_le_packet_now(void){
582     if (hci_stack->hci_packet_buffer_reserved) return 0;
583     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
584 }
585 
586 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
587     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
588     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
589 }
590 
591 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
592     if (hci_stack->hci_packet_buffer_reserved) return 0;
593     return hci_can_send_prepared_acl_packet_now(con_handle);
594 }
595 
596 #ifdef ENABLE_CLASSIC
597 int hci_can_send_acl_classic_packet_now(void){
598     if (hci_stack->hci_packet_buffer_reserved) return 0;
599     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
600 }
601 
602 int hci_can_send_prepared_sco_packet_now(void){
603     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
604     if (hci_have_usb_transport()){
605         return hci_stack->sco_can_send_now;
606     } else {
607         return hci_number_free_sco_slots() > 0;
608     }
609 }
610 
611 int hci_can_send_sco_packet_now(void){
612     if (hci_stack->hci_packet_buffer_reserved) return 0;
613     return hci_can_send_prepared_sco_packet_now();
614 }
615 
616 void hci_request_sco_can_send_now_event(void){
617     hci_stack->sco_waiting_for_can_send_now = 1;
618     hci_notify_if_sco_can_send_now();
619 }
620 #endif
621 
622 // used for internal checks in l2cap.c
623 int hci_is_packet_buffer_reserved(void){
624     return hci_stack->hci_packet_buffer_reserved;
625 }
626 
627 // reserves outgoing packet buffer. @returns 1 if successful
628 int hci_reserve_packet_buffer(void){
629     if (hci_stack->hci_packet_buffer_reserved) {
630         log_error("hci_reserve_packet_buffer called but buffer already reserved");
631         return 0;
632     }
633     hci_stack->hci_packet_buffer_reserved = 1;
634     return 1;
635 }
636 
637 void hci_release_packet_buffer(void){
638     hci_stack->hci_packet_buffer_reserved = 0;
639 }
640 
641 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
642 static int hci_transport_synchronous(void){
643     return hci_stack->hci_transport->can_send_packet_now == NULL;
644 }
645 
646 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
647 
648     // 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);
649 
650     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
651     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
652     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0)){
653         max_acl_data_packet_length = hci_stack->le_data_packets_length;
654     }
655 
656 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
657     if (hci_is_le_connection(connection)){
658         max_acl_data_packet_length = connection->le_max_tx_octets;
659     }
660 #endif
661 
662     log_debug("hci_send_acl_packet_fragments entered");
663 
664     int err;
665     // multiple packets could be send on a synchronous HCI transport
666     while (true){
667 
668         log_debug("hci_send_acl_packet_fragments loop entered");
669 
670         // get current data
671         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
672         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
673         int more_fragments = 0;
674 
675         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
676         if (current_acl_data_packet_length > max_acl_data_packet_length){
677             more_fragments = 1;
678             current_acl_data_packet_length = max_acl_data_packet_length;
679         }
680 
681         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
682         if (acl_header_pos > 0){
683             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
684             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
685             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
686         }
687 
688         // update header len
689         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
690 
691         // count packet
692         connection->num_packets_sent++;
693         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
694 
695         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
696         if (more_fragments){
697             // update start of next fragment to send
698             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
699         } else {
700             // done
701             hci_stack->acl_fragmentation_pos = 0;
702             hci_stack->acl_fragmentation_total_size = 0;
703         }
704 
705         // send packet
706         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
707         const int size = current_acl_data_packet_length + 4;
708         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
709         hci_stack->acl_fragmentation_tx_active = 1;
710         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
711 
712         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
713 
714         // done yet?
715         if (!more_fragments) break;
716 
717         // can send more?
718         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
719     }
720 
721     log_debug("hci_send_acl_packet_fragments loop over");
722 
723     // release buffer now for synchronous transport
724     if (hci_transport_synchronous()){
725         hci_stack->acl_fragmentation_tx_active = 0;
726         hci_release_packet_buffer();
727         hci_emit_transport_packet_sent();
728     }
729 
730     return err;
731 }
732 
733 // pre: caller has reserved the packet buffer
734 int hci_send_acl_packet_buffer(int size){
735 
736     // log_info("hci_send_acl_packet_buffer size %u", size);
737 
738     if (!hci_stack->hci_packet_buffer_reserved) {
739         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
740         return 0;
741     }
742 
743     uint8_t * packet = hci_stack->hci_packet_buffer;
744     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
745 
746     // check for free places on Bluetooth module
747     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
748         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
749         hci_release_packet_buffer();
750         hci_emit_transport_packet_sent();
751         return BTSTACK_ACL_BUFFERS_FULL;
752     }
753 
754     hci_connection_t *connection = hci_connection_for_handle( con_handle);
755     if (!connection) {
756         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
757         hci_release_packet_buffer();
758         hci_emit_transport_packet_sent();
759         return 0;
760     }
761 
762 #ifdef ENABLE_CLASSIC
763     hci_connection_timestamp(connection);
764 #endif
765 
766     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
767 
768     // setup data
769     hci_stack->acl_fragmentation_total_size = size;
770     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
771 
772     return hci_send_acl_packet_fragments(connection);
773 }
774 
775 #ifdef ENABLE_CLASSIC
776 // pre: caller has reserved the packet buffer
777 int hci_send_sco_packet_buffer(int size){
778 
779     // log_info("hci_send_acl_packet_buffer size %u", size);
780 
781     if (!hci_stack->hci_packet_buffer_reserved) {
782         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
783         return 0;
784     }
785 
786     uint8_t * packet = hci_stack->hci_packet_buffer;
787 
788     // skip checks in loopback mode
789     if (!hci_stack->loopback_mode){
790         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
791 
792         // check for free places on Bluetooth module
793         if (!hci_can_send_prepared_sco_packet_now()) {
794             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
795             hci_release_packet_buffer();
796             hci_emit_transport_packet_sent();
797             return BTSTACK_ACL_BUFFERS_FULL;
798         }
799 
800         // track send packet in connection struct
801         hci_connection_t *connection = hci_connection_for_handle( con_handle);
802         if (!connection) {
803             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
804             hci_release_packet_buffer();
805             hci_emit_transport_packet_sent();
806             return 0;
807         }
808 
809         if (hci_have_usb_transport()){
810             // token used
811             hci_stack->sco_can_send_now = 0;
812         } else {
813             if (hci_stack->synchronous_flow_control_enabled){
814                 connection->num_packets_sent++;
815             } else {
816                 connection->sco_tx_ready--;
817             }
818         }
819     }
820 
821     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
822     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
823 
824     if (hci_transport_synchronous()){
825         hci_release_packet_buffer();
826         hci_emit_transport_packet_sent();
827     }
828 
829     return err;
830 }
831 #endif
832 
833 static void acl_handler(uint8_t *packet, int size){
834 
835     // log_info("acl_handler: size %u", size);
836 
837     // get info
838     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
839     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
840     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
841     uint16_t acl_length         = READ_ACL_LENGTH(packet);
842 
843     // ignore non-registered handle
844     if (!conn){
845         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
846         return;
847     }
848 
849     // assert packet is complete
850     if ((acl_length + 4) != size){
851         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
852         return;
853     }
854 
855 #ifdef ENABLE_CLASSIC
856     // update idle timestamp
857     hci_connection_timestamp(conn);
858 #endif
859 
860 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
861     hci_stack->host_completed_packets = 1;
862     conn->num_packets_completed++;
863 #endif
864 
865     // handle different packet types
866     switch (acl_flags & 0x03) {
867 
868         case 0x01: // continuation fragment
869 
870             // sanity checks
871             if (conn->acl_recombination_pos == 0) {
872                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
873                 return;
874             }
875             if ((conn->acl_recombination_pos + acl_length) > (4 + HCI_ACL_BUFFER_SIZE)){
876                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
877                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
878                 conn->acl_recombination_pos = 0;
879                 return;
880             }
881 
882             // append fragment payload (header already stored)
883             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
884                          &packet[4], acl_length);
885             conn->acl_recombination_pos += acl_length;
886 
887             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
888             //        conn->acl_recombination_pos, conn->acl_recombination_length);
889 
890             // forward complete L2CAP packet if complete.
891             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4 + 4)){ // pos already incl. ACL header
892                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
893                 // reset recombination buffer
894                 conn->acl_recombination_length = 0;
895                 conn->acl_recombination_pos = 0;
896             }
897             break;
898 
899         case 0x02: { // first fragment
900 
901             // sanity check
902             if (conn->acl_recombination_pos) {
903                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
904                 conn->acl_recombination_pos = 0;
905             }
906 
907             // peek into L2CAP packet!
908             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
909 
910             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
911 
912             // compare fragment size to L2CAP packet size
913             if (acl_length >= (l2cap_length + 4)){
914                 // forward fragment as L2CAP packet
915                 hci_emit_acl_packet(packet, acl_length + 4);
916             } else {
917 
918                 if (acl_length > HCI_ACL_BUFFER_SIZE){
919                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
920                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
921                     return;
922                 }
923 
924                 // store first fragment and tweak acl length for complete package
925                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
926                              packet, acl_length + 4);
927                 conn->acl_recombination_pos    = acl_length + 4;
928                 conn->acl_recombination_length = l2cap_length;
929                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
930             }
931             break;
932 
933         }
934         default:
935             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
936             return;
937     }
938 
939     // execute main loop
940     hci_run();
941 }
942 
943 static void hci_shutdown_connection(hci_connection_t *conn){
944     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
945 
946 #ifdef ENABLE_CLASSIC
947 #ifdef ENABLE_SCO_OVER_HCI
948     int addr_type = conn->address_type;
949 #endif
950 #endif
951 
952     btstack_run_loop_remove_timer(&conn->timeout);
953 
954     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
955     btstack_memory_hci_connection_free( conn );
956 
957     // now it's gone
958     hci_emit_nr_connections_changed();
959 
960 #ifdef ENABLE_CLASSIC
961 #ifdef ENABLE_SCO_OVER_HCI
962     // update SCO
963     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
964         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
965     }
966 #endif
967 #endif
968 }
969 
970 #ifdef ENABLE_CLASSIC
971 
972 static const uint16_t packet_type_sizes[] = {
973     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
974     HCI_ACL_DH1_SIZE, 0, 0, 0,
975     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
976     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
977 };
978 static const uint8_t  packet_type_feature_requirement_bit[] = {
979      0, // 3 slot packets
980      1, // 5 slot packets
981     25, // EDR 2 mpbs
982     26, // EDR 3 mbps
983     39, // 3 slot EDR packts
984     40, // 5 slot EDR packet
985 };
986 static const uint16_t packet_type_feature_packet_mask[] = {
987     0x0f00, // 3 slot packets
988     0xf000, // 5 slot packets
989     0x1102, // EDR 2 mpbs
990     0x2204, // EDR 3 mbps
991     0x0300, // 3 slot EDR packts
992     0x3000, // 5 slot EDR packet
993 };
994 
995 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
996     // enable packet types based on size
997     uint16_t packet_types = 0;
998     unsigned int i;
999     for (i=0;i<16;i++){
1000         if (packet_type_sizes[i] == 0) continue;
1001         if (packet_type_sizes[i] <= buffer_size){
1002             packet_types |= 1 << i;
1003         }
1004     }
1005     // disable packet types due to missing local supported features
1006     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1007         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1008         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1009         if (feature_set) continue;
1010         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1011         packet_types &= ~packet_type_feature_packet_mask[i];
1012     }
1013     // flip bits for "may not be used"
1014     packet_types ^= 0x3306;
1015     return packet_types;
1016 }
1017 
1018 uint16_t hci_usable_acl_packet_types(void){
1019     return hci_stack->packet_types;
1020 }
1021 #endif
1022 
1023 uint8_t* hci_get_outgoing_packet_buffer(void){
1024     // hci packet buffer is >= acl data packet length
1025     return hci_stack->hci_packet_buffer;
1026 }
1027 
1028 uint16_t hci_max_acl_data_packet_length(void){
1029     return hci_stack->acl_data_packet_length;
1030 }
1031 
1032 #ifdef ENABLE_CLASSIC
1033 int hci_extended_sco_link_supported(void){
1034     // No. 31, byte 3, bit 7
1035     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1036 }
1037 #endif
1038 
1039 int hci_non_flushable_packet_boundary_flag_supported(void){
1040     // No. 54, byte 6, bit 6
1041     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1042 }
1043 
1044 static int gap_ssp_supported(void){
1045     // No. 51, byte 6, bit 3
1046     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1047 }
1048 
1049 static int hci_classic_supported(void){
1050 #ifdef ENABLE_CLASSIC
1051     // No. 37, byte 4, bit 5, = No BR/EDR Support
1052     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1053 #else
1054     return 0;
1055 #endif
1056 }
1057 
1058 static int hci_le_supported(void){
1059 #ifdef ENABLE_BLE
1060     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1061     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1062 #else
1063     return 0;
1064 #endif
1065 }
1066 
1067 #ifdef ENABLE_BLE
1068 
1069 /**
1070  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1071  */
1072 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1073     *addr_type = hci_stack->le_own_addr_type;
1074     if (hci_stack->le_own_addr_type){
1075         (void)memcpy(addr, hci_stack->le_random_address, 6);
1076     } else {
1077         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1078     }
1079 }
1080 
1081 #ifdef ENABLE_LE_CENTRAL
1082 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1083 
1084     int offset = 3;
1085     int num_reports = packet[offset];
1086     offset += 1;
1087 
1088     int i;
1089     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1090     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1091     for (i=0; (i<num_reports) && (offset < size);i++){
1092         // sanity checks on data_length:
1093         uint8_t data_length = packet[offset + 8];
1094         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1095         if ((offset + 9 + data_length + 1) > size)    return;
1096         // setup event
1097         uint8_t event_size = 10 + data_length;
1098         int pos = 0;
1099         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1100         event[pos++] = event_size;
1101         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1102         offset += 8;
1103         pos += 8;
1104         event[pos++] = packet[offset + 1 + data_length]; // rssi
1105         event[pos++] = data_length;
1106         offset++;
1107         (void)memcpy(&event[pos], &packet[offset], data_length);
1108         pos +=    data_length;
1109         offset += data_length + 1; // rssi
1110         hci_emit_event(event, pos, 1);
1111     }
1112 }
1113 #endif
1114 #endif
1115 
1116 #ifdef ENABLE_BLE
1117 #ifdef ENABLE_LE_PERIPHERAL
1118 static void hci_reenable_advertisements_if_needed(void){
1119     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1120         // get number of active le slave connections
1121         int num_slave_connections = 0;
1122         btstack_linked_list_iterator_t it;
1123         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1124         while (btstack_linked_list_iterator_has_next(&it)){
1125             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1126             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1127             if (con->state != OPEN) continue;
1128             if (con->role  != HCI_ROLE_SLAVE) continue;
1129             if (!hci_is_le_connection(con)) continue;
1130             num_slave_connections++;
1131         }
1132         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1133         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1134             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1135         }
1136     }
1137 }
1138 #endif
1139 #endif
1140 
1141 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1142 
1143 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1144     if (!hci_stack->config) return 0;
1145     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1146     // Limit baud rate for Broadcom chipsets to 3 mbps
1147     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1148         baud_rate = 3000000;
1149     }
1150     return baud_rate;
1151 }
1152 
1153 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1154     UNUSED(ds);
1155 
1156     switch (hci_stack->substate){
1157         case HCI_INIT_W4_SEND_RESET:
1158             log_info("Resend HCI Reset");
1159             hci_stack->substate = HCI_INIT_SEND_RESET;
1160             hci_stack->num_cmd_packets = 1;
1161             hci_run();
1162             break;
1163         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1164             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1165             if (hci_stack->hci_transport->reset_link){
1166                 hci_stack->hci_transport->reset_link();
1167             }
1168 
1169             /* fall through */
1170 
1171         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1172             log_info("Resend HCI Reset - CSR Warm Boot");
1173             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1174             hci_stack->num_cmd_packets = 1;
1175             hci_run();
1176             break;
1177         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1178             if (hci_stack->hci_transport->set_baudrate){
1179                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1180                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1181                 hci_stack->hci_transport->set_baudrate(baud_rate);
1182             }
1183             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1184             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1185                 if (hci_stack->hci_transport->reset_link){
1186                     log_info("Link Reset");
1187                     hci_stack->hci_transport->reset_link();
1188                 }
1189                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1190                 hci_run();
1191             }
1192             break;
1193         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1194             // otherwise continue
1195             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1196             hci_send_cmd(&hci_read_local_supported_commands);
1197             break;
1198         default:
1199             break;
1200     }
1201 }
1202 #endif
1203 
1204 static void hci_initializing_next_state(void){
1205     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1206 }
1207 
1208 // assumption: hci_can_send_command_packet_now() == true
1209 static void hci_initializing_run(void){
1210     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1211     switch (hci_stack->substate){
1212         case HCI_INIT_SEND_RESET:
1213             hci_state_reset();
1214 
1215 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1216             // prepare reset if command complete not received in 100ms
1217             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1218             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1219             btstack_run_loop_add_timer(&hci_stack->timeout);
1220 #endif
1221             // send command
1222             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1223             hci_send_cmd(&hci_reset);
1224             break;
1225         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1226             hci_send_cmd(&hci_read_local_version_information);
1227             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1228             break;
1229         case HCI_INIT_SEND_READ_LOCAL_NAME:
1230             hci_send_cmd(&hci_read_local_name);
1231             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1232             break;
1233 
1234 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1235         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1236             hci_state_reset();
1237             // prepare reset if command complete not received in 100ms
1238             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1239             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1240             btstack_run_loop_add_timer(&hci_stack->timeout);
1241             // send command
1242             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1243             hci_send_cmd(&hci_reset);
1244             break;
1245         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1246             hci_state_reset();
1247             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1248             hci_send_cmd(&hci_reset);
1249             break;
1250         case HCI_INIT_SEND_BAUD_CHANGE: {
1251             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1252             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1253             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1254             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1255             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1256             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1257             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1258             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1259                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1260                 btstack_run_loop_add_timer(&hci_stack->timeout);
1261             }
1262             break;
1263         }
1264         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1265             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1266             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1267             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1268             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1269             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1270             break;
1271         }
1272         case HCI_INIT_CUSTOM_INIT:
1273             // Custom initialization
1274             if (hci_stack->chipset && hci_stack->chipset->next_command){
1275                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1276                 int send_cmd = 0;
1277                 switch (hci_stack->chipset_result){
1278                     case BTSTACK_CHIPSET_VALID_COMMAND:
1279                         send_cmd = 1;
1280                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1281                         break;
1282                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1283                         send_cmd = 1;
1284                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1285                         log_info("CSR Warm Boot");
1286                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1287                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1288                         btstack_run_loop_add_timer(&hci_stack->timeout);
1289                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1290                             && hci_stack->config
1291                             && hci_stack->chipset
1292                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1293                             && hci_stack->hci_transport->set_baudrate
1294                             && hci_transport_uart_get_main_baud_rate()){
1295                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1296                         } else {
1297                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1298                         }
1299                         break;
1300                     default:
1301                         break;
1302                 }
1303 
1304                 if (send_cmd){
1305                     int size = 3 + hci_stack->hci_packet_buffer[2];
1306                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1307                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1308                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1309                     break;
1310                 }
1311                 log_info("Init script done");
1312 
1313                 // Init script download on Broadcom chipsets causes:
1314                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1315                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1316                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1317 
1318                     // - baud rate to reset, restore UART baud rate if needed
1319                     int need_baud_change = hci_stack->config
1320                         && hci_stack->chipset
1321                         && hci_stack->chipset->set_baudrate_command
1322                         && hci_stack->hci_transport->set_baudrate
1323                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1324                     if (need_baud_change) {
1325                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1326                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1327                         hci_stack->hci_transport->set_baudrate(baud_rate);
1328                     }
1329 
1330                     uint16_t bcm_delay_ms = 300;
1331                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1332                     //   -> Work around: wait here.
1333                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1334                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1335                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1336                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1337                     btstack_run_loop_add_timer(&hci_stack->timeout);
1338                     break;
1339                 }
1340             }
1341             // otherwise continue
1342             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1343             hci_send_cmd(&hci_read_local_supported_commands);
1344             break;
1345         case HCI_INIT_SET_BD_ADDR:
1346             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1347             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1348             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1349             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1350             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1351             break;
1352 #endif
1353 
1354         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1355             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1356             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1357             hci_send_cmd(&hci_read_local_supported_commands);
1358             break;
1359         case HCI_INIT_READ_BD_ADDR:
1360             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1361             hci_send_cmd(&hci_read_bd_addr);
1362             break;
1363         case HCI_INIT_READ_BUFFER_SIZE:
1364             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1365             hci_send_cmd(&hci_read_buffer_size);
1366             break;
1367         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1368             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1369             hci_send_cmd(&hci_read_local_supported_features);
1370             break;
1371 
1372 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1373         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1374             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1375             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1376             break;
1377         case HCI_INIT_HOST_BUFFER_SIZE:
1378             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1379             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1380                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1381             break;
1382 #endif
1383 
1384         case HCI_INIT_SET_EVENT_MASK:
1385             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1386             if (hci_le_supported()){
1387                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1388             } else {
1389                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1390                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1391             }
1392             break;
1393 
1394 #ifdef ENABLE_CLASSIC
1395         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1396             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1397             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1398             break;
1399         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1400             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1401             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1402             break;
1403         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1404             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1405             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1406             break;
1407         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1408             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1409             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1410             break;
1411         case HCI_INIT_WRITE_LOCAL_NAME: {
1412             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1413             hci_reserve_packet_buffer();
1414             uint8_t * packet = hci_stack->hci_packet_buffer;
1415             // construct HCI Command and send
1416             uint16_t opcode = hci_write_local_name.opcode;
1417             hci_stack->last_cmd_opcode = opcode;
1418             packet[0] = opcode & 0xff;
1419             packet[1] = opcode >> 8;
1420             packet[2] = DEVICE_NAME_LEN;
1421             memset(&packet[3], 0, DEVICE_NAME_LEN);
1422             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1423             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1424             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1425             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1426             // expand '00:00:00:00:00:00' in name with bd_addr
1427             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1428             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1429             break;
1430         }
1431         case HCI_INIT_WRITE_EIR_DATA: {
1432             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1433             hci_reserve_packet_buffer();
1434             uint8_t * packet = hci_stack->hci_packet_buffer;
1435             // construct HCI Command in-place and send
1436             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1437             hci_stack->last_cmd_opcode = opcode;
1438             uint16_t offset = 0;
1439             packet[offset++] = opcode & 0xff;
1440             packet[offset++] = opcode >> 8;
1441             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1442             packet[offset++] = 0;  // FEC not required
1443             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1444             if (hci_stack->eir_data){
1445                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1446                 ad_context_t context;
1447                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1448                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1449                     uint8_t size        = ad_iterator_get_data_len(&context);
1450                     const uint8_t *data = ad_iterator_get_data(&context);
1451                     // copy item
1452                     packet[offset++] = size + 1;
1453                     packet[offset++] = data_type;
1454                     memcpy(&packet[offset], data, size);
1455                     // update name item
1456                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1457                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1458                     }
1459                     offset += size;
1460                 }
1461             } else {
1462                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1463                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1464                 packet[offset++] = bytes_to_copy + 1;
1465                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1466                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1467                 // expand '00:00:00:00:00:00' in name with bd_addr
1468                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1469             }
1470             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1471             break;
1472         }
1473         case HCI_INIT_WRITE_INQUIRY_MODE:
1474             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1475             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1476             break;
1477         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1478             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1479             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1480             break;
1481         case HCI_INIT_WRITE_SCAN_ENABLE:
1482             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1483             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1484             break;
1485         // only sent if ENABLE_SCO_OVER_HCI is defined
1486         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1487             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1488             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1489             break;
1490         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1491             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1492             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1493             break;
1494         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1495         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1496             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1497             log_info("BCM: Route SCO data via HCI transport");
1498             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1499             break;
1500 
1501 #endif
1502 #ifdef ENABLE_BLE
1503         // LE INIT
1504         case HCI_INIT_LE_READ_BUFFER_SIZE:
1505             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1506             hci_send_cmd(&hci_le_read_buffer_size);
1507             break;
1508         case HCI_INIT_LE_SET_EVENT_MASK:
1509             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1510             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1511             break;
1512         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1513             // LE Supported Host = 1, Simultaneous Host = 0
1514             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1515             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1516             break;
1517 #endif
1518 
1519 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1520         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1521             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1522             hci_send_cmd(&hci_le_read_maximum_data_length);
1523             break;
1524         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1525             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1526             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1527             break;
1528 #endif
1529 
1530 #ifdef ENABLE_LE_CENTRAL
1531         case HCI_INIT_READ_WHITE_LIST_SIZE:
1532             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1533             hci_send_cmd(&hci_le_read_white_list_size);
1534             break;
1535         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1536             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1537             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1538             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);
1539             break;
1540 #endif
1541         default:
1542             return;
1543     }
1544 }
1545 
1546 static void hci_init_done(void){
1547     // done. tell the app
1548     log_info("hci_init_done -> HCI_STATE_WORKING");
1549     hci_stack->state = HCI_STATE_WORKING;
1550     hci_emit_state();
1551     hci_run();
1552 }
1553 
1554 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1555     bool command_completed = false;
1556     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1557         uint16_t opcode = little_endian_read_16(packet,3);
1558         if (opcode == hci_stack->last_cmd_opcode){
1559             command_completed = true;
1560             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1561         } else {
1562             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1563         }
1564     }
1565 
1566     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1567         uint8_t  status = packet[2];
1568         uint16_t opcode = little_endian_read_16(packet,4);
1569         if (opcode == hci_stack->last_cmd_opcode){
1570             if (status){
1571                 command_completed = true;
1572                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1573             } else {
1574                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1575             }
1576         } else {
1577             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1578         }
1579     }
1580 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1581     // Vendor == CSR
1582     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1583         // TODO: track actual command
1584         command_completed = true;
1585     }
1586 
1587     // Vendor == Toshiba
1588     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1589         // TODO: track actual command
1590         command_completed = true;
1591         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1592         hci_stack->num_cmd_packets = 1;
1593     }
1594 #endif
1595 
1596     return command_completed;
1597 }
1598 
1599 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1600 
1601     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1602 
1603     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1604 
1605 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1606 
1607     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1608     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1609     //
1610     // HCI Reset
1611     // Timeout 100 ms
1612     // HCI Reset
1613     // Command Complete Reset
1614     // HCI Read Local Version Information
1615     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1616     // hang...
1617     //
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_SEND_READ_LOCAL_VERSION_INFORMATION)){
1622 
1623         uint16_t opcode = little_endian_read_16(packet,3);
1624         if (opcode == hci_reset.opcode){
1625             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1626             return;
1627         }
1628     }
1629 
1630     // CSR & H5
1631     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1632     if (!command_completed
1633             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1634             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1635 
1636         uint16_t opcode = little_endian_read_16(packet,3);
1637         if (opcode == hci_reset.opcode){
1638             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1639             return;
1640         }
1641     }
1642 
1643     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1644     // fix: Correct substate and behave as command below
1645     if (command_completed){
1646         switch (hci_stack->substate){
1647             case HCI_INIT_SEND_RESET:
1648                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1649                 break;
1650             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1651                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1652                 break;
1653             default:
1654                 break;
1655         }
1656     }
1657 
1658 #endif
1659 
1660     if (!command_completed) return;
1661 
1662     bool need_baud_change = false;
1663     bool need_addr_change = false;
1664 
1665 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1666     need_baud_change = hci_stack->config
1667                         && hci_stack->chipset
1668                         && hci_stack->chipset->set_baudrate_command
1669                         && hci_stack->hci_transport->set_baudrate
1670                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1671 
1672     need_addr_change = hci_stack->custom_bd_addr_set
1673                         && hci_stack->chipset
1674                         && hci_stack->chipset->set_bd_addr_command;
1675 #endif
1676 
1677     switch(hci_stack->substate){
1678 
1679 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1680         case HCI_INIT_SEND_RESET:
1681             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1682             // fix: just correct substate and behave as command below
1683             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1684             btstack_run_loop_remove_timer(&hci_stack->timeout);
1685             break;
1686         case HCI_INIT_W4_SEND_RESET:
1687             btstack_run_loop_remove_timer(&hci_stack->timeout);
1688             break;
1689         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1690             log_info("Received local name, need baud change %d", (int) need_baud_change);
1691             if (need_baud_change){
1692                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1693                 return;
1694             }
1695             // skip baud change
1696             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1697             return;
1698         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1699             // for STLC2500D, baud rate change already happened.
1700             // for others, baud rate gets changed now
1701             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1702                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1703                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1704                 hci_stack->hci_transport->set_baudrate(baud_rate);
1705             }
1706             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1707             return;
1708         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1709             btstack_run_loop_remove_timer(&hci_stack->timeout);
1710             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1711             return;
1712         case HCI_INIT_W4_CUSTOM_INIT:
1713             // repeat custom init
1714             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1715             return;
1716 #else
1717         case HCI_INIT_W4_SEND_RESET:
1718             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1719             return ;
1720 #endif
1721 
1722         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1723             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1724               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1725                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1726                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1727                 return;
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 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1736         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1737             if (need_baud_change){
1738                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1739                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1740                 hci_stack->hci_transport->set_baudrate(baud_rate);
1741             }
1742             if (need_addr_change){
1743                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1744                 return;
1745             }
1746             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1747             return;
1748         case HCI_INIT_W4_SET_BD_ADDR:
1749             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1750             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1751             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1752                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1753                 return;
1754             }
1755             // skipping st warm boot
1756             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1757             return;
1758         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1759             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1760             return;
1761 #endif
1762         case HCI_INIT_W4_READ_BD_ADDR:
1763             // only read buffer size if supported
1764             if (hci_stack->local_supported_commands[0] & 0x01) {
1765                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1766                 return;
1767             }
1768             // skipping read buffer size
1769             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1770             return;
1771         case HCI_INIT_W4_SET_EVENT_MASK:
1772             // skip Classic init commands for LE only chipsets
1773             if (!hci_classic_supported()){
1774 #ifdef ENABLE_BLE
1775                 if (hci_le_supported()){
1776                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1777                     return;
1778                 }
1779 #endif
1780                 log_error("Neither BR/EDR nor LE supported");
1781                 hci_init_done();
1782                 return;
1783             }
1784             if (!gap_ssp_supported()){
1785                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1786                 return;
1787             }
1788             break;
1789 #ifdef ENABLE_BLE
1790         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1791             // skip write le host if not supported (e.g. on LE only EM9301)
1792             if (hci_stack->local_supported_commands[0] & 0x02) break;
1793             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1794             return;
1795 
1796 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1797         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1798             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1799             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1800                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1801                 return;
1802             }
1803             // explicit fall through to reduce repetitions
1804 
1805 #ifdef ENABLE_LE_CENTRAL
1806             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1807 #else
1808             hci_init_done();
1809 #endif
1810             return;
1811 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1812 
1813 #endif  /* ENABLE_BLE */
1814 
1815         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1816             // skip write secure connections host support if not supported or disabled
1817             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1] & 0x02) == 0) {
1818                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1819                 return;
1820             }
1821             break;
1822 
1823 #ifdef ENABLE_SCO_OVER_HCI
1824         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1825             // skip write synchronous flow control if not supported
1826             if (hci_stack->local_supported_commands[0] & 0x04) break;
1827             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1828 
1829             /* fall through */
1830 
1831         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1832             // skip write default erroneous data reporting if not supported
1833             if (hci_stack->local_supported_commands[0] & 0x08) break;
1834             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1835 
1836             /* fall through */
1837 
1838         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1839             // skip bcm set sco pcm config on non-Broadcom chipsets
1840             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1841             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1842 
1843             /* fall through */
1844 
1845         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1846             if (!hci_le_supported()){
1847                 // SKIP LE init for Classic only configuration
1848                 hci_init_done();
1849                 return;
1850             }
1851             break;
1852 
1853 #else /* !ENABLE_SCO_OVER_HCI */
1854 
1855         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1856 #ifdef ENABLE_BLE
1857             if (hci_le_supported()){
1858                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1859                 return;
1860             }
1861 #endif
1862             // SKIP LE init for Classic only configuration
1863             hci_init_done();
1864             return;
1865 #endif /* ENABLE_SCO_OVER_HCI */
1866 
1867 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1868 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1869         // Response to command before init done state -> init done
1870         case (HCI_INIT_DONE-1):
1871             hci_init_done();
1872             return;
1873 #endif
1874 
1875         default:
1876             break;
1877     }
1878     hci_initializing_next_state();
1879 }
1880 
1881 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1882     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1883     bd_addr_t bd_address;
1884     (void)memcpy(&bd_address, conn->address, 6);
1885 
1886 #ifdef ENABLE_CLASSIC
1887     // cache needed data
1888     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1889 #endif
1890 
1891     // connection failed, remove entry
1892     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1893     btstack_memory_hci_connection_free( conn );
1894 
1895 #ifdef ENABLE_CLASSIC
1896     // notify client if dedicated bonding
1897     if (notify_dedicated_bonding_failed){
1898         log_info("hci notify_dedicated_bonding_failed");
1899         hci_emit_dedicated_bonding_result(bd_address, status);
1900     }
1901 
1902     // if authentication error, also delete link key
1903     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1904         gap_drop_link_key_for_bd_addr(bd_address);
1905     }
1906 #endif
1907 }
1908 
1909 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1910     // SSP Controller
1911     if (features[6] & (1 << 3)){
1912         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1913     }
1914     // eSCO
1915     if (features[3] & (1<<7)){
1916         conn->remote_supported_features[0] |= 1;
1917     }
1918     // Extended features
1919     if (features[7] & (1<<7)){
1920         conn->remote_supported_features[0] |= 2;
1921     }
1922 }
1923 
1924 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1925     // SSP Host
1926     if (features[0] & (1 << 0)){
1927         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1928     }
1929 }
1930 
1931 static void hci_handle_remote_features_received(hci_connection_t * conn){
1932     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1933     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1934     if (conn->bonding_flags & BONDING_DEDICATED){
1935         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1936     }
1937 }
1938 
1939 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1940     // handle BT initialization
1941     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1942         hci_initializing_event_handler(packet, size);
1943     }
1944 
1945     // help with BT sleep
1946     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1947         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1948         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1949         hci_initializing_next_state();
1950     }
1951 }
1952 
1953 static void event_handler(uint8_t *packet, int size){
1954 
1955     uint16_t event_length = packet[1];
1956 
1957     // assert packet is complete
1958     if (size != (event_length + 2)){
1959         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1960         return;
1961     }
1962 
1963     bd_addr_t addr;
1964     bd_addr_type_t addr_type;
1965     hci_con_handle_t handle;
1966     hci_connection_t * conn;
1967     int i;
1968     int create_connection_cmd;
1969 
1970 #ifdef ENABLE_CLASSIC
1971     uint8_t link_type;
1972 #endif
1973 
1974     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1975 
1976     switch (hci_event_packet_get_type(packet)) {
1977 
1978         case HCI_EVENT_COMMAND_COMPLETE:
1979             // get num cmd packets - limit to 1 to reduce complexity
1980             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1981 
1982             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1983                 if (packet[5]) break;
1984                 // terminate, name 248 chars
1985                 packet[6+248] = 0;
1986                 log_info("local name: %s", &packet[6]);
1987             }
1988             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1989                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1990                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1991                     uint16_t acl_len = little_endian_read_16(packet, 6);
1992                     uint16_t sco_len = packet[8];
1993 
1994                     // determine usable ACL/SCO payload size
1995                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1996                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1997 
1998                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1999                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
2000 
2001                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2002                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2003                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2004                 }
2005             }
2006             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
2007                 if (packet[5] == 0){
2008                     uint8_t event[5];
2009                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2010                     event[1] = 3;
2011                     (void)memcpy(&event[2], &packet[6], 3);
2012                     hci_emit_event(event, sizeof(event), 1);
2013                 }
2014             }
2015 #ifdef ENABLE_BLE
2016             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
2017                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2018                 hci_stack->le_acl_packets_total_num  = packet[8];
2019                 // determine usable ACL payload size
2020                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2021                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2022                 }
2023                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2024             }
2025 #endif
2026 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2027             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
2028                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2029                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2030                 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);
2031             }
2032 #endif
2033 #ifdef ENABLE_LE_CENTRAL
2034             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
2035                 hci_stack->le_whitelist_capacity = packet[6];
2036                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2037             }
2038 #endif
2039             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
2040                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2041 				hci_stack->local_bd_addr);
2042                 log_info("Local Address, Status: 0x%02x: Addr: %s",
2043                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2044 #ifdef ENABLE_CLASSIC
2045                 if (hci_stack->link_key_db){
2046                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2047                 }
2048 #endif
2049             }
2050 #ifdef ENABLE_CLASSIC
2051             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2052                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2053             }
2054             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2055                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2056                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2057                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2058                     hci_emit_event(event, sizeof(event), 1);
2059                 }
2060             }
2061 #endif
2062 
2063             // Note: HCI init checks
2064             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2065                 (void)memcpy(hci_stack->local_supported_features,
2066 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2067 			     8);
2068 
2069 #ifdef ENABLE_CLASSIC
2070                 // determine usable ACL packet types based on host buffer size and supported features
2071                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2072                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2073 #endif
2074                 // Classic/LE
2075                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2076             }
2077             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2078                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2079                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2080                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2081                 // map Cypress to Broadcom
2082                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2083                     log_info("Treat Cypress as Broadcom");
2084                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2085                     little_endian_store_16(packet, 10, manufacturer);
2086                 }
2087                 hci_stack->manufacturer = manufacturer;
2088                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2089                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2090                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2091             }
2092             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2093                 hci_stack->local_supported_commands[0] =
2094                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2095                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2096                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2097                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2098                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2099                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2100                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2101                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2102                 hci_stack->local_supported_commands[1] =
2103                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+ 2] & 0x40) >> 6) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2104                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+32] & 0x08) >> 2);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2105                 log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2106             }
2107 #ifdef ENABLE_CLASSIC
2108             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2109                 if (packet[5] == 0){
2110                     hci_stack->synchronous_flow_control_enabled = 1;
2111                 }
2112             }
2113             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2114                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2115                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2116                 conn   = hci_connection_for_handle(handle);
2117                 if (!conn) break;
2118                 if (status == 0){
2119                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2120                     log_info("Handle %x04x key Size: %u", handle, key_size);
2121                     conn->encryption_key_size = key_size;
2122                 } else {
2123                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2124                     conn->encryption_key_size = 1;
2125                 }
2126                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2127                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2128             }
2129 #endif
2130             break;
2131 
2132         case HCI_EVENT_COMMAND_STATUS:
2133             // get num cmd packets - limit to 1 to reduce complexity
2134             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2135 
2136             // check command status to detected failed outgoing connections
2137             create_connection_cmd = 0;
2138 #ifdef ENABLE_CLASSIC
2139             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2140                 create_connection_cmd = 1;
2141             }
2142 #endif
2143 #ifdef ENABLE_LE_CENTRAL
2144             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2145                 create_connection_cmd = 1;
2146             }
2147 #endif
2148             if (create_connection_cmd) {
2149                 uint8_t status = hci_event_command_status_get_status(packet);
2150                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2151                 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);
2152 
2153                 // reset outgoing address info
2154                 memset(hci_stack->outgoing_addr, 0, 6);
2155                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2156 
2157                 // error => outgoing connection failed
2158                 if ((conn != NULL) && (status != 0)){
2159                     hci_handle_connection_failed(conn, status);
2160                 }
2161             }
2162             break;
2163 
2164         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2165             if (size < 3) return;
2166             uint16_t num_handles = packet[2];
2167             if (size != (3 + num_handles * 4)) return;
2168             uint16_t offset = 3;
2169             for (i=0; i<num_handles;i++){
2170                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2171                 offset += 2;
2172                 uint16_t num_packets = little_endian_read_16(packet, offset);
2173                 offset += 2;
2174 
2175                 conn = hci_connection_for_handle(handle);
2176                 if (!conn){
2177                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2178                     continue;
2179                 }
2180 
2181                 if (conn->num_packets_sent >= num_packets){
2182                     conn->num_packets_sent -= num_packets;
2183                 } else {
2184                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2185                     conn->num_packets_sent = 0;
2186                 }
2187                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2188 
2189 #ifdef ENABLE_CLASSIC
2190                 // For SCO, we do the can_send_now_check here
2191                 hci_notify_if_sco_can_send_now();
2192 #endif
2193             }
2194             break;
2195         }
2196 
2197 #ifdef ENABLE_CLASSIC
2198         case HCI_EVENT_INQUIRY_COMPLETE:
2199             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2200                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2201                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2202                 hci_emit_event(event, sizeof(event), 1);
2203             }
2204             break;
2205         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2206             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2207                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2208             }
2209             break;
2210         case HCI_EVENT_CONNECTION_REQUEST:
2211             reverse_bd_addr(&packet[2], addr);
2212             if (hci_stack->gap_classic_accept_callback != NULL){
2213                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2214                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2215                     bd_addr_copy(hci_stack->decline_addr, addr);
2216                     break;
2217                 }
2218             }
2219 
2220             // TODO: eval COD 8-10
2221             link_type = packet[11];
2222             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2223             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2224             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2225             if (!conn) {
2226                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2227             }
2228             if (!conn) {
2229                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2230                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2231                 bd_addr_copy(hci_stack->decline_addr, addr);
2232                 break;
2233             }
2234             conn->role  = HCI_ROLE_SLAVE;
2235             conn->state = RECEIVED_CONNECTION_REQUEST;
2236             // store info about eSCO
2237             if (link_type == 0x02){
2238                 conn->remote_supported_features[0] |= 1;
2239             }
2240             hci_run();
2241             break;
2242 
2243         case HCI_EVENT_CONNECTION_COMPLETE:
2244             // Connection management
2245             reverse_bd_addr(&packet[5], addr);
2246             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2247             addr_type = BD_ADDR_TYPE_ACL;
2248             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2249             if (conn) {
2250                 if (!packet[2]){
2251                     conn->state = OPEN;
2252                     conn->con_handle = little_endian_read_16(packet, 3);
2253 
2254                     // queue get remote feature
2255                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2256 
2257                     // queue set supervision timeout if we're master
2258                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2259                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2260                     }
2261 
2262                     // restart timer
2263                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2264                     btstack_run_loop_add_timer(&conn->timeout);
2265 
2266                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2267 
2268                     hci_emit_nr_connections_changed();
2269                 } else {
2270                     // connection failed
2271                     hci_handle_connection_failed(conn, packet[2]);
2272                 }
2273             }
2274             break;
2275 
2276         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2277             reverse_bd_addr(&packet[5], addr);
2278             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2279             if (packet[2]){
2280                 // connection failed
2281                 break;
2282             }
2283             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2284             if (!conn) {
2285                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2286             }
2287             if (!conn) {
2288                 break;
2289             }
2290             conn->state = OPEN;
2291             conn->con_handle = little_endian_read_16(packet, 3);
2292 
2293 #ifdef ENABLE_SCO_OVER_HCI
2294             // update SCO
2295             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2296                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2297             }
2298             // trigger can send now
2299             if (hci_have_usb_transport()){
2300                 hci_stack->sco_can_send_now = 1;
2301             }
2302 #endif
2303             break;
2304 
2305         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2306             handle = little_endian_read_16(packet, 3);
2307             conn = hci_connection_for_handle(handle);
2308             if (!conn) break;
2309             if (!packet[2]){
2310                 const uint8_t * features = &packet[5];
2311                 hci_handle_remote_features_page_0(conn, features);
2312 
2313                 // read extended features if possible
2314                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2315                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2316                     break;
2317                 }
2318             }
2319             hci_handle_remote_features_received(conn);
2320             break;
2321 
2322         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2323             handle = little_endian_read_16(packet, 3);
2324             conn = hci_connection_for_handle(handle);
2325             if (!conn) break;
2326             // status = ok, page = 1
2327             if (!packet[2] && packet[5] == 1){
2328                 const uint8_t * features = &packet[7];
2329                 hci_handle_remote_features_page_1(conn, features);
2330             }
2331             hci_handle_remote_features_received(conn);
2332             break;
2333 
2334         case HCI_EVENT_LINK_KEY_REQUEST:
2335             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2336             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2337             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2338             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2339             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2340             hci_run();
2341             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2342             return;
2343 
2344         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2345             reverse_bd_addr(&packet[2], addr);
2346             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2347             if (!conn) break;
2348             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2349             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2350             // Change Connection Encryption keeps link key type
2351             if (link_key_type != CHANGED_COMBINATION_KEY){
2352                 conn->link_key_type = link_key_type;
2353             }
2354             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2355             // still forward event to allow dismiss of pairing dialog
2356             break;
2357         }
2358 
2359         case HCI_EVENT_PIN_CODE_REQUEST:
2360             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2361             // non-bondable mode: pin code negative reply will be sent
2362             if (!hci_stack->bondable){
2363                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2364                 hci_run();
2365                 return;
2366             }
2367             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2368             if (!hci_stack->link_key_db) break;
2369             hci_event_pin_code_request_get_bd_addr(packet, addr);
2370             hci_stack->link_key_db->delete_link_key(addr);
2371             break;
2372 
2373         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2374             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2375             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2376             break;
2377 
2378         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2379             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2380             if (!hci_stack->ssp_auto_accept) break;
2381             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2382             break;
2383 
2384         case HCI_EVENT_USER_PASSKEY_REQUEST:
2385             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2386             if (!hci_stack->ssp_auto_accept) break;
2387             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2388             break;
2389         case HCI_EVENT_MODE_CHANGE:
2390             handle = hci_event_mode_change_get_handle(packet);
2391             conn = hci_connection_for_handle(handle);
2392             if (!conn) break;
2393             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2394             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2395             break;
2396 #endif
2397 
2398         case HCI_EVENT_ENCRYPTION_CHANGE:
2399             handle = hci_event_encryption_change_get_connection_handle(packet);
2400             conn = hci_connection_for_handle(handle);
2401             if (!conn) break;
2402             if (hci_event_encryption_change_get_status(packet) == 0) {
2403                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2404                 if (encryption_enabled){
2405                     if (hci_is_le_connection(conn)){
2406                         // For LE, we accept connection as encrypted
2407                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2408                     }
2409 #ifdef ENABLE_CLASSIC
2410                     else {
2411                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2412                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2413                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2414                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2415                             log_info("SC during pairing, but only E0 now -> abort");
2416                             conn->state = conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2417                             break;
2418                         }
2419 
2420                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2421                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2422                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2423                         } else {
2424                             // if not, pretend everything is perfect
2425                             conn->encryption_key_size = 16;
2426                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2427                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2428                         }
2429                     }
2430 #endif
2431                 } else {
2432                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2433                 }
2434             }
2435 
2436             break;
2437 
2438 #ifdef ENABLE_CLASSIC
2439         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2440             handle = little_endian_read_16(packet, 3);
2441             conn = hci_connection_for_handle(handle);
2442             if (!conn) break;
2443 
2444             // dedicated bonding: send result and disconnect
2445             if (conn->bonding_flags & BONDING_DEDICATED){
2446                 conn->bonding_flags &= ~BONDING_DEDICATED;
2447                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2448                 conn->bonding_status = packet[2];
2449                 break;
2450             }
2451 
2452             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2453                 // link key sufficient for requested security
2454                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2455                 break;
2456             }
2457             // not enough
2458             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2459             break;
2460 #endif
2461 
2462         // HCI_EVENT_DISCONNECTION_COMPLETE
2463         // has been split, to first notify stack before shutting connection down
2464         // see end of function, too.
2465         case HCI_EVENT_DISCONNECTION_COMPLETE:
2466             if (packet[2]) break;   // status != 0
2467             handle = little_endian_read_16(packet, 3);
2468             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2469             if (hci_stack->acl_fragmentation_total_size > 0) {
2470                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2471                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2472                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2473                     hci_stack->acl_fragmentation_total_size = 0;
2474                     hci_stack->acl_fragmentation_pos = 0;
2475                     if (release_buffer){
2476                         hci_release_packet_buffer();
2477                     }
2478                 }
2479             }
2480 
2481             conn = hci_connection_for_handle(handle);
2482             if (!conn) break;
2483             // mark connection for shutdown
2484             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2485 
2486             // emit dedicatd bonding event
2487             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2488                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2489             }
2490 
2491 #ifdef ENABLE_BLE
2492 #ifdef ENABLE_LE_PERIPHERAL
2493             // re-enable advertisements for le connections if active
2494             if (hci_is_le_connection(conn)){
2495                 hci_reenable_advertisements_if_needed();
2496             }
2497 #endif
2498 #endif
2499             break;
2500 
2501         case HCI_EVENT_HARDWARE_ERROR:
2502             log_error("Hardware Error: 0x%02x", packet[2]);
2503             if (hci_stack->hardware_error_callback){
2504                 (*hci_stack->hardware_error_callback)(packet[2]);
2505             } else {
2506                 // if no special requests, just reboot stack
2507                 hci_power_control_off();
2508                 hci_power_control_on();
2509             }
2510             break;
2511 
2512 #ifdef ENABLE_CLASSIC
2513         case HCI_EVENT_ROLE_CHANGE:
2514             if (packet[2]) break;   // status != 0
2515             reverse_bd_addr(&packet[3], addr);
2516             addr_type = BD_ADDR_TYPE_ACL;
2517             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2518             if (!conn) break;
2519             conn->role = packet[9];
2520             break;
2521 #endif
2522 
2523         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2524             // release packet buffer only for asynchronous transport and if there are not further fragements
2525             if (hci_transport_synchronous()) {
2526                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2527                 return; // instead of break: to avoid re-entering hci_run()
2528             }
2529             hci_stack->acl_fragmentation_tx_active = 0;
2530             if (hci_stack->acl_fragmentation_total_size) break;
2531             hci_release_packet_buffer();
2532 
2533             // L2CAP receives this event via the hci_emit_event below
2534 
2535 #ifdef ENABLE_CLASSIC
2536             // For SCO, we do the can_send_now_check here
2537             hci_notify_if_sco_can_send_now();
2538 #endif
2539             break;
2540 
2541 #ifdef ENABLE_CLASSIC
2542         case HCI_EVENT_SCO_CAN_SEND_NOW:
2543             // For SCO, we do the can_send_now_check here
2544             hci_stack->sco_can_send_now = 1;
2545             hci_notify_if_sco_can_send_now();
2546             return;
2547 
2548         // explode inquriy results for easier consumption
2549         case HCI_EVENT_INQUIRY_RESULT:
2550         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2551         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2552             gap_inquiry_explode(packet, size);
2553             break;
2554 #endif
2555 
2556 #ifdef ENABLE_BLE
2557         case HCI_EVENT_LE_META:
2558             switch (packet[2]){
2559 #ifdef ENABLE_LE_CENTRAL
2560                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2561                     // log_info("advertising report received");
2562                     if (!hci_stack->le_scanning_enabled) break;
2563                     le_handle_advertisement_report(packet, size);
2564                     break;
2565 #endif
2566                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2567                     // Connection management
2568                     reverse_bd_addr(&packet[8], addr);
2569                     addr_type = (bd_addr_type_t)packet[7];
2570                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2571                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2572 
2573 #ifdef ENABLE_LE_CENTRAL
2574                     // if auto-connect, remove from whitelist in both roles
2575                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2576                         hci_remove_from_whitelist(addr_type, addr);
2577                     }
2578                     // handle error: error is reported only to the initiator -> outgoing connection
2579                     if (packet[3]){
2580 
2581                         // handle cancelled outgoing connection
2582                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2583                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2584                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2585                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2586                             conn = gap_get_outgoing_connection();
2587                         }
2588 
2589                         // outgoing connection establishment is done
2590                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2591                         // remove entry
2592                         if (conn){
2593                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2594                             btstack_memory_hci_connection_free( conn );
2595                         }
2596                         break;
2597                     }
2598 #endif
2599                     // on success, both hosts receive connection complete event
2600                     if (packet[6] == HCI_ROLE_MASTER){
2601 #ifdef ENABLE_LE_CENTRAL
2602                         // if we're master, it was an outgoing connection and we're done with it
2603                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2604 #endif
2605                     } else {
2606 #ifdef ENABLE_LE_PERIPHERAL
2607                         // if we're slave, it was an incoming connection, advertisements have stopped
2608                         hci_stack->le_advertisements_active = 0;
2609 #endif
2610                     }
2611                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2612                     if (!conn){
2613                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2614                     }
2615                     // no memory, sorry.
2616                     if (!conn){
2617                         break;
2618                     }
2619 
2620                     conn->state = OPEN;
2621                     conn->role  = packet[6];
2622                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2623                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2624 
2625 #ifdef ENABLE_LE_PERIPHERAL
2626                     if (packet[6] == HCI_ROLE_SLAVE){
2627                         hci_reenable_advertisements_if_needed();
2628                     }
2629 #endif
2630 
2631                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2632 
2633                     // restart timer
2634                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2635                     // btstack_run_loop_add_timer(&conn->timeout);
2636 
2637                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2638 
2639                     hci_emit_nr_connections_changed();
2640                     break;
2641 
2642                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2643                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2644                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2645                     conn = hci_connection_for_handle(handle);
2646                     if (!conn) break;
2647                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2648                     break;
2649 
2650                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2651                     // connection
2652                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2653                     conn = hci_connection_for_handle(handle);
2654                     if (conn) {
2655                         // read arguments
2656                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2657                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2658                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2659                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2660 
2661                         // validate against current connection parameter range
2662                         le_connection_parameter_range_t existing_range;
2663                         gap_get_connection_parameter_range(&existing_range);
2664                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2665                         if (update_parameter){
2666                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2667                             conn->le_conn_interval_min = le_conn_interval_min;
2668                             conn->le_conn_interval_max = le_conn_interval_max;
2669                             conn->le_conn_latency = le_conn_latency;
2670                             conn->le_supervision_timeout = le_supervision_timeout;
2671                         } else {
2672                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2673                         }
2674                     }
2675                     break;
2676 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2677                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2678                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2679                     conn = hci_connection_for_handle(handle);
2680                     if (conn) {
2681                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2682                     }
2683                     break;
2684 #endif
2685                 default:
2686                     break;
2687             }
2688             break;
2689 #endif
2690         case HCI_EVENT_VENDOR_SPECIFIC:
2691             // Vendor specific commands often create vendor specific event instead of num completed packets
2692             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2693             switch (hci_stack->manufacturer){
2694                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2695                     hci_stack->num_cmd_packets = 1;
2696                     break;
2697                 default:
2698                     break;
2699             }
2700             break;
2701         default:
2702             break;
2703     }
2704 
2705     handle_event_for_current_stack_state(packet, size);
2706 
2707     // notify upper stack
2708 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2709 
2710     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2711     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2712         if (!packet[2]){
2713             handle = little_endian_read_16(packet, 3);
2714             hci_connection_t * aConn = hci_connection_for_handle(handle);
2715             if (aConn) {
2716                 // discard connection if app did not trigger a reconnect in the event handler
2717                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2718                     hci_shutdown_connection(aConn);
2719                 }
2720             }
2721         }
2722     }
2723 
2724 	// execute main loop
2725 	hci_run();
2726 }
2727 
2728 #ifdef ENABLE_CLASSIC
2729 
2730 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2731 static void sco_schedule_tx(hci_connection_t * conn);
2732 
2733 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2734     log_debug("SCO TX Timeout");
2735     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2736     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2737     if (!conn) return;
2738 
2739     // trigger send
2740     conn->sco_tx_ready = 1;
2741     // extra packet if CVSD but SCO buffer is too short
2742     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2743         conn->sco_tx_ready++;
2744     }
2745     hci_notify_if_sco_can_send_now();
2746 }
2747 
2748 
2749 #define SCO_TX_AFTER_RX_MS (6)
2750 
2751 static void sco_schedule_tx(hci_connection_t * conn){
2752 
2753     uint32_t now = btstack_run_loop_get_time_ms();
2754     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2755     int time_delta_ms = sco_tx_ms - now;
2756 
2757     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2758 
2759     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2760     btstack_run_loop_set_timer(timer, time_delta_ms);
2761     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2762     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2763     btstack_run_loop_add_timer(timer);
2764 }
2765 
2766 static void sco_handler(uint8_t * packet, uint16_t size){
2767     // lookup connection struct
2768     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2769     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2770     if (!conn) return;
2771 
2772     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2773     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2774         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2775             packet[2] = 0x3c;
2776             memmove(&packet[3], &packet[23], 63);
2777             size = 63;
2778         }
2779     }
2780 
2781     if (hci_have_usb_transport()){
2782         // Nothing to do
2783     } else {
2784         // 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);
2785         if (hci_stack->synchronous_flow_control_enabled == 0){
2786             uint32_t now = btstack_run_loop_get_time_ms();
2787 
2788             if (!conn->sco_rx_valid){
2789                 // ignore first 10 packets
2790                 conn->sco_rx_count++;
2791                 // log_debug("sco rx count %u", conn->sco_rx_count);
2792                 if (conn->sco_rx_count == 10) {
2793                     // use first timestamp as is and pretent it just started
2794                     conn->sco_rx_ms = now;
2795                     conn->sco_rx_valid = 1;
2796                     conn->sco_rx_count = 0;
2797                     sco_schedule_tx(conn);
2798                 }
2799             } else {
2800                 // track expected arrival timme
2801                 conn->sco_rx_count++;
2802                 conn->sco_rx_ms += 7;
2803                 int delta = (int32_t) (now - conn->sco_rx_ms);
2804                 if (delta > 0){
2805                     conn->sco_rx_ms++;
2806                 }
2807                 // log_debug("sco rx %u", conn->sco_rx_ms);
2808                 sco_schedule_tx(conn);
2809             }
2810         }
2811     }
2812     // deliver to app
2813     if (hci_stack->sco_packet_handler) {
2814         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2815     }
2816 
2817 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2818     conn->num_packets_completed++;
2819     hci_stack->host_completed_packets = 1;
2820     hci_run();
2821 #endif
2822 }
2823 #endif
2824 
2825 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2826     hci_dump_packet(packet_type, 1, packet, size);
2827     switch (packet_type) {
2828         case HCI_EVENT_PACKET:
2829             event_handler(packet, size);
2830             break;
2831         case HCI_ACL_DATA_PACKET:
2832             acl_handler(packet, size);
2833             break;
2834 #ifdef ENABLE_CLASSIC
2835         case HCI_SCO_DATA_PACKET:
2836             sco_handler(packet, size);
2837             break;
2838 #endif
2839         default:
2840             break;
2841     }
2842 }
2843 
2844 /**
2845  * @brief Add event packet handler.
2846  */
2847 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2848     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2849 }
2850 
2851 
2852 /** Register HCI packet handlers */
2853 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2854     hci_stack->acl_packet_handler = handler;
2855 }
2856 
2857 #ifdef ENABLE_CLASSIC
2858 /**
2859  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2860  */
2861 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2862     hci_stack->sco_packet_handler = handler;
2863 }
2864 #endif
2865 
2866 static void hci_state_reset(void){
2867     // no connections yet
2868     hci_stack->connections = NULL;
2869 
2870     // keep discoverable/connectable as this has been requested by the client(s)
2871     // hci_stack->discoverable = 0;
2872     // hci_stack->connectable = 0;
2873     // hci_stack->bondable = 1;
2874     // hci_stack->own_addr_type = 0;
2875 
2876     // buffer is free
2877     hci_stack->hci_packet_buffer_reserved = 0;
2878 
2879     // no pending cmds
2880     hci_stack->decline_reason = 0;
2881     hci_stack->new_scan_enable_value = 0xff;
2882 
2883     // LE
2884 #ifdef ENABLE_BLE
2885     memset(hci_stack->le_random_address, 0, 6);
2886     hci_stack->le_random_address_set = 0;
2887 #endif
2888 #ifdef ENABLE_LE_CENTRAL
2889     hci_stack->le_scanning_active  = 0;
2890     hci_stack->le_scan_type = 0xff;
2891     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2892     hci_stack->le_whitelist = 0;
2893     hci_stack->le_whitelist_capacity = 0;
2894 #endif
2895 }
2896 
2897 #ifdef ENABLE_CLASSIC
2898 /**
2899  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2900  */
2901 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2902     // store and open remote device db
2903     hci_stack->link_key_db = link_key_db;
2904     if (hci_stack->link_key_db) {
2905         hci_stack->link_key_db->open();
2906     }
2907 }
2908 #endif
2909 
2910 void hci_init(const hci_transport_t *transport, const void *config){
2911 
2912 #ifdef HAVE_MALLOC
2913     if (!hci_stack) {
2914         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2915     }
2916 #else
2917     hci_stack = &hci_stack_static;
2918 #endif
2919     memset(hci_stack, 0, sizeof(hci_stack_t));
2920 
2921     // reference to use transport layer implementation
2922     hci_stack->hci_transport = transport;
2923 
2924     // reference to used config
2925     hci_stack->config = config;
2926 
2927     // setup pointer for outgoing packet buffer
2928     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2929 
2930     // max acl payload size defined in config.h
2931     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2932 
2933     // register packet handlers with transport
2934     transport->register_packet_handler(&packet_handler);
2935 
2936     hci_stack->state = HCI_STATE_OFF;
2937 
2938     // class of device
2939     hci_stack->class_of_device = 0x007a020c; // Smartphone
2940 
2941     // bondable by default
2942     hci_stack->bondable = 1;
2943 
2944 #ifdef ENABLE_CLASSIC
2945     // classic name
2946     hci_stack->local_name = default_classic_name;
2947 
2948     // Master slave policy
2949     hci_stack->master_slave_policy = 1;
2950 
2951     // Allow Role Switch
2952     hci_stack->allow_role_switch = 1;
2953 
2954     // Default / minimum security level = 2
2955     hci_stack->gap_security_level = LEVEL_2;
2956 
2957     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2958     hci_stack->gap_required_encyrption_key_size = 16;
2959 #endif
2960 
2961     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2962     hci_stack->ssp_enable = 1;
2963     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2964     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2965     hci_stack->ssp_auto_accept = 1;
2966 
2967     // Secure Connections: enable (requires support from Controller)
2968     hci_stack->secure_connections_enable = true;
2969 
2970     // voice setting - signed 16 bit pcm data with CVSD over the air
2971     hci_stack->sco_voice_setting = 0x60;
2972 
2973 #ifdef ENABLE_LE_CENTRAL
2974     // connection parameter to use for outgoing connections
2975     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2976     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2977     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2978     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2979     hci_stack->le_connection_latency      = 4;         // 4
2980     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2981     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2982     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2983 
2984     // default LE Scanning
2985     hci_stack->le_scan_interval = 0x1e0;
2986     hci_stack->le_scan_window   =  0x30;
2987 #endif
2988 
2989 #ifdef ENABLE_LE_PERIPHERAL
2990     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2991 #endif
2992 
2993     // connection parameter range used to answer connection parameter update requests in l2cap
2994     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2995     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2996     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2997     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2998     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2999     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3000 
3001     hci_state_reset();
3002 }
3003 
3004 /**
3005  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3006  */
3007 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3008     hci_stack->chipset = chipset_driver;
3009 
3010     // reset chipset driver - init is also called on power_up
3011     if (hci_stack->chipset && hci_stack->chipset->init){
3012         hci_stack->chipset->init(hci_stack->config);
3013     }
3014 }
3015 
3016 /**
3017  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3018  */
3019 void hci_set_control(const btstack_control_t *hardware_control){
3020     // references to used control implementation
3021     hci_stack->control = hardware_control;
3022     // init with transport config
3023     hardware_control->init(hci_stack->config);
3024 }
3025 
3026 void hci_close(void){
3027     // close remote device db
3028     if (hci_stack->link_key_db) {
3029         hci_stack->link_key_db->close();
3030     }
3031 
3032     btstack_linked_list_iterator_t lit;
3033     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3034     while (btstack_linked_list_iterator_has_next(&lit)){
3035         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3036         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3037         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3038         hci_shutdown_connection(connection);
3039     }
3040 
3041     hci_power_control(HCI_POWER_OFF);
3042 
3043 #ifdef HAVE_MALLOC
3044     free(hci_stack);
3045 #endif
3046     hci_stack = NULL;
3047 }
3048 
3049 #ifdef ENABLE_CLASSIC
3050 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3051     // validate ranage and set
3052     if (encryption_key_size < 7)  return;
3053     if (encryption_key_size > 16) return;
3054     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3055 }
3056 
3057 void gap_set_security_level(gap_security_level_t security_level){
3058     hci_stack->gap_security_level = security_level;
3059 }
3060 
3061 gap_security_level_t gap_get_security_level(void){
3062     return hci_stack->gap_security_level;
3063 }
3064 #endif
3065 
3066 #ifdef ENABLE_CLASSIC
3067 void gap_set_class_of_device(uint32_t class_of_device){
3068     hci_stack->class_of_device = class_of_device;
3069 }
3070 
3071 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3072     hci_stack->default_link_policy_settings = default_link_policy_settings;
3073 }
3074 
3075 void gap_set_allow_role_switch(bool allow_role_switch){
3076     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3077 }
3078 
3079 uint8_t hci_get_allow_role_switch(void){
3080     return  hci_stack->allow_role_switch;
3081 }
3082 
3083 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3084     hci_stack->link_supervision_timeout = link_supervision_timeout;
3085 }
3086 
3087 void hci_disable_l2cap_timeout_check(void){
3088     disable_l2cap_timeouts = 1;
3089 }
3090 #endif
3091 
3092 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3093 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3094 void hci_set_bd_addr(bd_addr_t addr){
3095     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3096     hci_stack->custom_bd_addr_set = 1;
3097 }
3098 #endif
3099 
3100 // State-Module-Driver overview
3101 // state                    module  low-level
3102 // HCI_STATE_OFF             off      close
3103 // HCI_STATE_INITIALIZING,   on       open
3104 // HCI_STATE_WORKING,        on       open
3105 // HCI_STATE_HALTING,        on       open
3106 // HCI_STATE_SLEEPING,    off/sleep   close
3107 // HCI_STATE_FALLING_ASLEEP  on       open
3108 
3109 static int hci_power_control_on(void){
3110 
3111     // power on
3112     int err = 0;
3113     if (hci_stack->control && hci_stack->control->on){
3114         err = (*hci_stack->control->on)();
3115     }
3116     if (err){
3117         log_error( "POWER_ON failed");
3118         hci_emit_hci_open_failed();
3119         return err;
3120     }
3121 
3122     // int chipset driver
3123     if (hci_stack->chipset && hci_stack->chipset->init){
3124         hci_stack->chipset->init(hci_stack->config);
3125     }
3126 
3127     // init transport
3128     if (hci_stack->hci_transport->init){
3129         hci_stack->hci_transport->init(hci_stack->config);
3130     }
3131 
3132     // open transport
3133     err = hci_stack->hci_transport->open();
3134     if (err){
3135         log_error( "HCI_INIT failed, turning Bluetooth off again");
3136         if (hci_stack->control && hci_stack->control->off){
3137             (*hci_stack->control->off)();
3138         }
3139         hci_emit_hci_open_failed();
3140         return err;
3141     }
3142     return 0;
3143 }
3144 
3145 static void hci_power_control_off(void){
3146 
3147     log_info("hci_power_control_off");
3148 
3149     // close low-level device
3150     hci_stack->hci_transport->close();
3151 
3152     log_info("hci_power_control_off - hci_transport closed");
3153 
3154     // power off
3155     if (hci_stack->control && hci_stack->control->off){
3156         (*hci_stack->control->off)();
3157     }
3158 
3159     log_info("hci_power_control_off - control closed");
3160 
3161     hci_stack->state = HCI_STATE_OFF;
3162 }
3163 
3164 static void hci_power_control_sleep(void){
3165 
3166     log_info("hci_power_control_sleep");
3167 
3168 #if 0
3169     // don't close serial port during sleep
3170 
3171     // close low-level device
3172     hci_stack->hci_transport->close(hci_stack->config);
3173 #endif
3174 
3175     // sleep mode
3176     if (hci_stack->control && hci_stack->control->sleep){
3177         (*hci_stack->control->sleep)();
3178     }
3179 
3180     hci_stack->state = HCI_STATE_SLEEPING;
3181 }
3182 
3183 static int hci_power_control_wake(void){
3184 
3185     log_info("hci_power_control_wake");
3186 
3187     // wake on
3188     if (hci_stack->control && hci_stack->control->wake){
3189         (*hci_stack->control->wake)();
3190     }
3191 
3192 #if 0
3193     // open low-level device
3194     int err = hci_stack->hci_transport->open(hci_stack->config);
3195     if (err){
3196         log_error( "HCI_INIT failed, turning Bluetooth off again");
3197         if (hci_stack->control && hci_stack->control->off){
3198             (*hci_stack->control->off)();
3199         }
3200         hci_emit_hci_open_failed();
3201         return err;
3202     }
3203 #endif
3204 
3205     return 0;
3206 }
3207 
3208 static void hci_power_transition_to_initializing(void){
3209     // set up state machine
3210     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3211     hci_stack->hci_packet_buffer_reserved = 0;
3212     hci_stack->state = HCI_STATE_INITIALIZING;
3213     hci_stack->substate = HCI_INIT_SEND_RESET;
3214 }
3215 
3216 int hci_power_control(HCI_POWER_MODE power_mode){
3217 
3218     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3219 
3220     int err = 0;
3221     switch (hci_stack->state){
3222 
3223         case HCI_STATE_OFF:
3224             switch (power_mode){
3225                 case HCI_POWER_ON:
3226                     err = hci_power_control_on();
3227                     if (err) {
3228                         log_error("hci_power_control_on() error %d", err);
3229                         return err;
3230                     }
3231                     hci_power_transition_to_initializing();
3232                     break;
3233                 case HCI_POWER_OFF:
3234                     // do nothing
3235                     break;
3236                 case HCI_POWER_SLEEP:
3237                     // do nothing (with SLEEP == OFF)
3238                     break;
3239             }
3240             break;
3241 
3242         case HCI_STATE_INITIALIZING:
3243             switch (power_mode){
3244                 case HCI_POWER_ON:
3245                     // do nothing
3246                     break;
3247                 case HCI_POWER_OFF:
3248                     // no connections yet, just turn it off
3249                     hci_power_control_off();
3250                     break;
3251                 case HCI_POWER_SLEEP:
3252                     // no connections yet, just turn it off
3253                     hci_power_control_sleep();
3254                     break;
3255             }
3256             break;
3257 
3258         case HCI_STATE_WORKING:
3259             switch (power_mode){
3260                 case HCI_POWER_ON:
3261                     // do nothing
3262                     break;
3263                 case HCI_POWER_OFF:
3264                     // see hci_run
3265                     hci_stack->state = HCI_STATE_HALTING;
3266                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3267                     break;
3268                 case HCI_POWER_SLEEP:
3269                     // see hci_run
3270                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3271                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3272                     break;
3273             }
3274             break;
3275 
3276         case HCI_STATE_HALTING:
3277             switch (power_mode){
3278                 case HCI_POWER_ON:
3279                     hci_power_transition_to_initializing();
3280                     break;
3281                 case HCI_POWER_OFF:
3282                     // do nothing
3283                     break;
3284                 case HCI_POWER_SLEEP:
3285                     // see hci_run
3286                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3287                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3288                     break;
3289             }
3290             break;
3291 
3292         case HCI_STATE_FALLING_ASLEEP:
3293             switch (power_mode){
3294                 case HCI_POWER_ON:
3295 
3296 #ifdef HAVE_PLATFORM_IPHONE_OS
3297                     // nothing to do, if H4 supports power management
3298                     if (btstack_control_iphone_power_management_enabled()){
3299                         hci_stack->state = HCI_STATE_INITIALIZING;
3300                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3301                         break;
3302                     }
3303 #endif
3304                     hci_power_transition_to_initializing();
3305                     break;
3306                 case HCI_POWER_OFF:
3307                     // see hci_run
3308                     hci_stack->state = HCI_STATE_HALTING;
3309                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3310                     break;
3311                 case HCI_POWER_SLEEP:
3312                     // do nothing
3313                     break;
3314             }
3315             break;
3316 
3317         case HCI_STATE_SLEEPING:
3318             switch (power_mode){
3319                 case HCI_POWER_ON:
3320 
3321 #ifdef HAVE_PLATFORM_IPHONE_OS
3322                     // nothing to do, if H4 supports power management
3323                     if (btstack_control_iphone_power_management_enabled()){
3324                         hci_stack->state = HCI_STATE_INITIALIZING;
3325                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3326                         hci_update_scan_enable();
3327                         break;
3328                     }
3329 #endif
3330                     err = hci_power_control_wake();
3331                     if (err) return err;
3332                     hci_power_transition_to_initializing();
3333                     break;
3334                 case HCI_POWER_OFF:
3335                     hci_stack->state = HCI_STATE_HALTING;
3336                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3337                     break;
3338                 case HCI_POWER_SLEEP:
3339                     // do nothing
3340                     break;
3341             }
3342             break;
3343     }
3344 
3345     // create internal event
3346 	hci_emit_state();
3347 
3348 	// trigger next/first action
3349 	hci_run();
3350 
3351     return 0;
3352 }
3353 
3354 
3355 #ifdef ENABLE_CLASSIC
3356 
3357 static void hci_update_scan_enable(void){
3358     // 2 = page scan, 1 = inq scan
3359     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3360     hci_run();
3361 }
3362 
3363 void gap_discoverable_control(uint8_t enable){
3364     if (enable) enable = 1; // normalize argument
3365 
3366     if (hci_stack->discoverable == enable){
3367         hci_emit_discoverable_enabled(hci_stack->discoverable);
3368         return;
3369     }
3370 
3371     hci_stack->discoverable = enable;
3372     hci_update_scan_enable();
3373 }
3374 
3375 void gap_connectable_control(uint8_t enable){
3376     if (enable) enable = 1; // normalize argument
3377 
3378     // don't emit event
3379     if (hci_stack->connectable == enable) return;
3380 
3381     hci_stack->connectable = enable;
3382     hci_update_scan_enable();
3383 }
3384 #endif
3385 
3386 void gap_local_bd_addr(bd_addr_t address_buffer){
3387     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3388 }
3389 
3390 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3391 static void hci_host_num_completed_packets(void){
3392 
3393     // create packet manually as arrays are not supported and num_commands should not get reduced
3394     hci_reserve_packet_buffer();
3395     uint8_t * packet = hci_get_outgoing_packet_buffer();
3396 
3397     uint16_t size = 0;
3398     uint16_t num_handles = 0;
3399     packet[size++] = 0x35;
3400     packet[size++] = 0x0c;
3401     size++;  // skip param len
3402     size++;  // skip num handles
3403 
3404     // add { handle, packets } entries
3405     btstack_linked_item_t * it;
3406     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3407         hci_connection_t * connection = (hci_connection_t *) it;
3408         if (connection->num_packets_completed){
3409             little_endian_store_16(packet, size, connection->con_handle);
3410             size += 2;
3411             little_endian_store_16(packet, size, connection->num_packets_completed);
3412             size += 2;
3413             //
3414             num_handles++;
3415             connection->num_packets_completed = 0;
3416         }
3417     }
3418 
3419     packet[2] = size - 3;
3420     packet[3] = num_handles;
3421 
3422     hci_stack->host_completed_packets = 0;
3423 
3424     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3425     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3426 
3427     // release packet buffer for synchronous transport implementations
3428     if (hci_transport_synchronous()){
3429         hci_release_packet_buffer();
3430         hci_emit_transport_packet_sent();
3431     }
3432 }
3433 #endif
3434 
3435 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3436     UNUSED(ds);
3437     hci_stack->substate = HCI_HALTING_CLOSE;
3438     // allow packet handlers to defer final shutdown
3439     hci_emit_state();
3440     hci_run();
3441 }
3442 
3443 static bool hci_run_acl_fragments(void){
3444     if (hci_stack->acl_fragmentation_total_size > 0) {
3445         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3446         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3447         if (connection) {
3448             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3449                 hci_send_acl_packet_fragments(connection);
3450                 return true;
3451             }
3452         } else {
3453             // connection gone -> discard further fragments
3454             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3455             hci_stack->acl_fragmentation_total_size = 0;
3456             hci_stack->acl_fragmentation_pos = 0;
3457         }
3458     }
3459     return false;
3460 }
3461 
3462 #ifdef ENABLE_CLASSIC
3463 static bool hci_run_general_gap_classic(void){
3464 
3465     // decline incoming connections
3466     if (hci_stack->decline_reason){
3467         uint8_t reason = hci_stack->decline_reason;
3468         hci_stack->decline_reason = 0;
3469         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3470         return true;
3471     }
3472     // send scan enable
3473     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3474         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3475         hci_stack->new_scan_enable_value = 0xff;
3476         return true;
3477     }
3478     // start/stop inquiry
3479     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3480         uint8_t duration = hci_stack->inquiry_state;
3481         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3482         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3483         return true;
3484     }
3485     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3486         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3487         hci_send_cmd(&hci_inquiry_cancel);
3488         return true;
3489     }
3490     // remote name request
3491     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3492         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3493         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3494                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3495         return true;
3496     }
3497     // pairing
3498     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3499         uint8_t state = hci_stack->gap_pairing_state;
3500         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3501         switch (state){
3502             case GAP_PAIRING_STATE_SEND_PIN:
3503                 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);
3504                 break;
3505             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3506                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3507                 break;
3508             case GAP_PAIRING_STATE_SEND_PASSKEY:
3509                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3510                 break;
3511             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3512                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3513                 break;
3514             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3515                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3516                 break;
3517             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3518                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3519                 break;
3520             default:
3521                 break;
3522         }
3523         return true;
3524     }
3525     return false;
3526 }
3527 #endif
3528 
3529 #ifdef ENABLE_BLE
3530 static bool hci_run_general_gap_le(void){
3531 
3532     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3533 
3534     if (hci_stack->state != HCI_STATE_WORKING) return false;
3535     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3536 
3537 #ifdef ENABLE_LE_CENTRAL
3538     // parameter change requires scanning to be stopped first
3539     if (hci_stack->le_scan_type != 0xff) {
3540         if (hci_stack->le_scanning_active){
3541             hci_stack->le_scanning_active = 0;
3542             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3543         } else {
3544             int scan_type = (int) hci_stack->le_scan_type;
3545             hci_stack->le_scan_type = 0xff;
3546             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);
3547         }
3548         return true;
3549     }
3550     // finally, we can enable/disable le scan
3551     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3552         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3553         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3554         return true;
3555     }
3556 #endif
3557 #ifdef ENABLE_LE_PERIPHERAL
3558     // le advertisement control
3559     if (hci_stack->le_advertisements_todo){
3560         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3561     }
3562     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3563         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3564         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3565         return true;
3566     }
3567     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3568         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3569         hci_send_cmd(&hci_le_set_advertising_parameters,
3570                      hci_stack->le_advertisements_interval_min,
3571                      hci_stack->le_advertisements_interval_max,
3572                      hci_stack->le_advertisements_type,
3573                      hci_stack->le_own_addr_type,
3574                      hci_stack->le_advertisements_direct_address_type,
3575                      hci_stack->le_advertisements_direct_address,
3576                      hci_stack->le_advertisements_channel_map,
3577                      hci_stack->le_advertisements_filter_policy);
3578         return true;
3579     }
3580     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3581         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3582         uint8_t adv_data_clean[31];
3583         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3584         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3585                      hci_stack->le_advertisements_data_len);
3586         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3587         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3588         return true;
3589     }
3590     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3591         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3592         uint8_t scan_data_clean[31];
3593         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3594         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3595                      hci_stack->le_scan_response_data_len);
3596         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3597         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3598         return true;
3599     }
3600     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3601         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3602         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3603         return true;
3604     }
3605 #endif
3606 
3607 #ifdef ENABLE_LE_CENTRAL
3608     //
3609     // LE Whitelist Management
3610     //
3611 
3612     // check if whitelist needs modification
3613     btstack_linked_list_iterator_t lit;
3614     int modification_pending = 0;
3615     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3616     while (btstack_linked_list_iterator_has_next(&lit)){
3617         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3618         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3619             modification_pending = 1;
3620             break;
3621         }
3622     }
3623 
3624     if (modification_pending){
3625         // stop connnecting if modification pending
3626         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3627             hci_send_cmd(&hci_le_create_connection_cancel);
3628             return true;
3629         }
3630 
3631         // add/remove entries
3632         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3633         while (btstack_linked_list_iterator_has_next(&lit)){
3634             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3635             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3636                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3637                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3638                 return true;
3639             }
3640             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3641                 bd_addr_t address;
3642                 bd_addr_type_t address_type = entry->address_type;
3643                 (void)memcpy(address, entry->address, 6);
3644                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3645                 btstack_memory_whitelist_entry_free(entry);
3646                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3647                 return true;
3648             }
3649         }
3650     }
3651 
3652     // start connecting
3653     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3654          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3655         bd_addr_t null_addr;
3656         memset(null_addr, 0, 6);
3657         hci_send_cmd(&hci_le_create_connection,
3658                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3659                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3660                      1,         // use whitelist
3661                      0,         // peer address type
3662                      null_addr, // peer bd addr
3663                      hci_stack->le_own_addr_type, // our addr type:
3664                      hci_stack->le_connection_interval_min,    // conn interval min
3665                      hci_stack->le_connection_interval_max,    // conn interval max
3666                      hci_stack->le_connection_latency,         // conn latency
3667                      hci_stack->le_supervision_timeout,        // conn latency
3668                      hci_stack->le_minimum_ce_length,          // min ce length
3669                      hci_stack->le_maximum_ce_length           // max ce length
3670         );
3671         return true;
3672     }
3673 #endif
3674     return false;
3675 }
3676 #endif
3677 
3678 static bool hci_run_general_pending_commmands(void){
3679     btstack_linked_item_t * it;
3680     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3681         hci_connection_t * connection = (hci_connection_t *) it;
3682 
3683         switch(connection->state){
3684             case SEND_CREATE_CONNECTION:
3685                 switch(connection->address_type){
3686 #ifdef ENABLE_CLASSIC
3687                     case BD_ADDR_TYPE_ACL:
3688                         log_info("sending hci_create_connection");
3689                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3690                         break;
3691 #endif
3692                     default:
3693 #ifdef ENABLE_BLE
3694 #ifdef ENABLE_LE_CENTRAL
3695                         // track outgoing connection
3696                         hci_stack->outgoing_addr_type = connection->address_type;
3697                         (void)memcpy(hci_stack->outgoing_addr,
3698                                      connection->address, 6);
3699                         log_info("sending hci_le_create_connection");
3700                         hci_send_cmd(&hci_le_create_connection,
3701                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3702                                      hci_stack->le_connection_scan_window,      // conn scan windows
3703                                      0,         // don't use whitelist
3704                                      connection->address_type, // peer address type
3705                                      connection->address,      // peer bd addr
3706                                      hci_stack->le_own_addr_type, // our addr type:
3707                                      hci_stack->le_connection_interval_min,    // conn interval min
3708                                      hci_stack->le_connection_interval_max,    // conn interval max
3709                                      hci_stack->le_connection_latency,         // conn latency
3710                                      hci_stack->le_supervision_timeout,        // conn latency
3711                                      hci_stack->le_minimum_ce_length,          // min ce length
3712                                      hci_stack->le_maximum_ce_length          // max ce length
3713                         );
3714                         connection->state = SENT_CREATE_CONNECTION;
3715 #endif
3716 #endif
3717                         break;
3718                 }
3719                 return true;
3720 
3721 #ifdef ENABLE_CLASSIC
3722             case RECEIVED_CONNECTION_REQUEST:
3723                 connection->role  = HCI_ROLE_SLAVE;
3724                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3725                     log_info("sending hci_accept_connection_request");
3726                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3727                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3728                 }
3729                 return true;
3730 #endif
3731 
3732 #ifdef ENABLE_BLE
3733 #ifdef ENABLE_LE_CENTRAL
3734             case SEND_CANCEL_CONNECTION:
3735                 connection->state = SENT_CANCEL_CONNECTION;
3736                 hci_send_cmd(&hci_le_create_connection_cancel);
3737                 return true;
3738 #endif
3739 #endif
3740             case SEND_DISCONNECT:
3741                 connection->state = SENT_DISCONNECT;
3742                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3743                 return true;
3744 
3745             default:
3746                 break;
3747         }
3748 
3749         // no further commands if connection is about to get shut down
3750         if (connection->state == SENT_DISCONNECT) continue;
3751 
3752         if (connection->authentication_flags & READ_RSSI){
3753             connectionClearAuthenticationFlags(connection, READ_RSSI);
3754             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3755             return true;
3756         }
3757 
3758 #ifdef ENABLE_CLASSIC
3759 
3760         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3761             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3762             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3763             return true;
3764         }
3765 
3766         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3767             log_info("responding to link key request");
3768             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3769             link_key_t link_key;
3770             link_key_type_t link_key_type;
3771             if ( hci_stack->link_key_db
3772                  && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3773                  && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level)){
3774                 connection->link_key_type = link_key_type;
3775                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3776             } else {
3777                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3778             }
3779             return true;
3780         }
3781 
3782         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3783             log_info("denying to pin request");
3784             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3785             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3786             return true;
3787         }
3788 
3789         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3790             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3791             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3792             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3793                 // tweak authentication requirements
3794                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3795                 if (connection->bonding_flags & BONDING_DEDICATED){
3796                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3797                 }
3798                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3799                     authreq |= 1;
3800                 }
3801                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3802             } else {
3803                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3804             }
3805             return true;
3806         }
3807 
3808         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3809             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3810             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3811             return true;
3812         }
3813 
3814         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3815             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3816             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3817             return true;
3818         }
3819 
3820         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3821             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3822             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3823             return true;
3824         }
3825 
3826         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3827             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3828             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3829             return true;
3830         }
3831 
3832         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3833             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3834             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3835             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3836             return true;
3837         }
3838 
3839         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3840             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3841             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3842             return true;
3843         }
3844 
3845         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3846             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3847             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3848             return true;
3849         }
3850         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3851             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3852             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3853             return true;
3854         }
3855 #endif
3856 
3857         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3858             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3859             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3860             return true;
3861         }
3862 
3863 #ifdef ENABLE_CLASSIC
3864         uint16_t sniff_min_interval;
3865         switch (connection->sniff_min_interval){
3866             case 0:
3867                 break;
3868             case 0xffff:
3869                 connection->sniff_min_interval = 0;
3870                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3871                 return true;
3872             default:
3873                 sniff_min_interval = connection->sniff_min_interval;
3874                 connection->sniff_min_interval = 0;
3875                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3876                 return true;
3877         }
3878 #endif
3879 
3880 #ifdef ENABLE_BLE
3881         switch (connection->le_con_parameter_update_state){
3882             // response to L2CAP CON PARAMETER UPDATE REQUEST
3883             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3884                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3885                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3886                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3887                              0x0000, 0xffff);
3888                 return true;
3889             case CON_PARAMETER_UPDATE_REPLY:
3890                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3891                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3892                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3893                              0x0000, 0xffff);
3894                 return true;
3895             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3896                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3897                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3898                 return true;
3899             default:
3900                 break;
3901         }
3902         if (connection->le_phy_update_all_phys != 0xff){
3903             uint8_t all_phys = connection->le_phy_update_all_phys;
3904             connection->le_phy_update_all_phys = 0xff;
3905             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);
3906             return true;
3907         }
3908 #endif
3909     }
3910     return false;
3911 }
3912 
3913 static void hci_run(void){
3914 
3915     bool done;
3916 
3917     // send continuation fragments first, as they block the prepared packet buffer
3918     done = hci_run_acl_fragments();
3919     if (done) return;
3920 
3921 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3922     // send host num completed packets next as they don't require num_cmd_packets > 0
3923     if (!hci_can_send_comand_packet_transport()) return;
3924     if (hci_stack->host_completed_packets){
3925         hci_host_num_completed_packets();
3926         return;
3927     }
3928 #endif
3929 
3930     if (!hci_can_send_command_packet_now()) return;
3931 
3932     // global/non-connection oriented commands
3933 
3934 
3935 #ifdef ENABLE_CLASSIC
3936     // general gap classic
3937     done = hci_run_general_gap_classic();
3938     if (done) return;
3939 #endif
3940 
3941 #ifdef ENABLE_BLE
3942     // general gap le
3943     done = hci_run_general_gap_le();
3944     if (done) return;
3945 #endif
3946 
3947     // send pending HCI commands
3948     done = hci_run_general_pending_commmands();
3949     if (done) return;
3950 
3951     // stack state sub statemachines
3952     hci_connection_t * connection;
3953     switch (hci_stack->state){
3954         case HCI_STATE_INITIALIZING:
3955             hci_initializing_run();
3956             break;
3957 
3958         case HCI_STATE_HALTING:
3959 
3960             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3961             switch (hci_stack->substate){
3962                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3963                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3964 
3965 #ifdef ENABLE_BLE
3966 #ifdef ENABLE_LE_CENTRAL
3967                     // free whitelist entries
3968                     {
3969                         btstack_linked_list_iterator_t lit;
3970                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3971                         while (btstack_linked_list_iterator_has_next(&lit)){
3972                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3973                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3974                             btstack_memory_whitelist_entry_free(entry);
3975                         }
3976                     }
3977 #endif
3978 #endif
3979                     // close all open connections
3980                     connection =  (hci_connection_t *) hci_stack->connections;
3981                     if (connection){
3982                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3983                         if (!hci_can_send_command_packet_now()) return;
3984 
3985                         // check state
3986                         if (connection->state == SENT_DISCONNECT) return;
3987                         connection->state = SENT_DISCONNECT;
3988 
3989                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3990 
3991                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3992                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3993 
3994                         // ... which would be ignored anyway as we shutdown (free) the connection now
3995                         hci_shutdown_connection(connection);
3996 
3997                         // finally, send the disconnect command
3998                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3999                         return;
4000                     }
4001 
4002                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4003                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4004                         log_info("HCI_STATE_HALTING: wait 50 ms");
4005                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4006                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4007                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4008                         btstack_run_loop_add_timer(&hci_stack->timeout);
4009                         break;
4010                     }
4011 
4012                     /* fall through */
4013 
4014                 case HCI_HALTING_CLOSE:
4015                     log_info("HCI_STATE_HALTING, calling off");
4016 
4017                     // switch mode
4018                     hci_power_control_off();
4019 
4020                     log_info("HCI_STATE_HALTING, emitting state");
4021                     hci_emit_state();
4022                     log_info("HCI_STATE_HALTING, done");
4023                     break;
4024 
4025                 case HCI_HALTING_W4_TIMER:
4026                     // keep waiting
4027 
4028                     break;
4029                 default:
4030                     break;
4031             }
4032 
4033             break;
4034 
4035         case HCI_STATE_FALLING_ASLEEP:
4036             switch(hci_stack->substate) {
4037                 case HCI_FALLING_ASLEEP_DISCONNECT:
4038                     log_info("HCI_STATE_FALLING_ASLEEP");
4039                     // close all open connections
4040                     connection =  (hci_connection_t *) hci_stack->connections;
4041 
4042 #ifdef HAVE_PLATFORM_IPHONE_OS
4043                     // don't close connections, if H4 supports power management
4044                     if (btstack_control_iphone_power_management_enabled()){
4045                         connection = NULL;
4046                     }
4047 #endif
4048                     if (connection){
4049 
4050                         // send disconnect
4051                         if (!hci_can_send_command_packet_now()) return;
4052 
4053                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4054                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
4055 
4056                         // send disconnected event right away - causes higher layer connections to get closed, too.
4057                         hci_shutdown_connection(connection);
4058                         return;
4059                     }
4060 
4061                     if (hci_classic_supported()){
4062                         // disable page and inquiry scan
4063                         if (!hci_can_send_command_packet_now()) return;
4064 
4065                         log_info("HCI_STATE_HALTING, disabling inq scans");
4066                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4067 
4068                         // continue in next sub state
4069                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4070                         break;
4071                     }
4072 
4073                     /* fall through */
4074 
4075                 case HCI_FALLING_ASLEEP_COMPLETE:
4076                     log_info("HCI_STATE_HALTING, calling sleep");
4077 #ifdef HAVE_PLATFORM_IPHONE_OS
4078                     // don't actually go to sleep, if H4 supports power management
4079                     if (btstack_control_iphone_power_management_enabled()){
4080                         // SLEEP MODE reached
4081                         hci_stack->state = HCI_STATE_SLEEPING;
4082                         hci_emit_state();
4083                         break;
4084                     }
4085 #endif
4086                     // switch mode
4087                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4088                     hci_emit_state();
4089                     break;
4090 
4091                 default:
4092                     break;
4093             }
4094             break;
4095 
4096         default:
4097             break;
4098     }
4099 }
4100 
4101 int hci_send_cmd_packet(uint8_t *packet, int size){
4102     // house-keeping
4103 
4104     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4105         hci_stack->loopback_mode = packet[3];
4106     }
4107 
4108 #ifdef ENABLE_CLASSIC
4109     bd_addr_t addr;
4110     hci_connection_t * conn;
4111 
4112     // create_connection?
4113     if (IS_COMMAND(packet, hci_create_connection)){
4114         reverse_bd_addr(&packet[3], addr);
4115         log_info("Create_connection to %s", bd_addr_to_str(addr));
4116 
4117         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4118         if (!conn){
4119             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4120             if (!conn){
4121                 // notify client that alloc failed
4122                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4123                 return -1; // packet not sent to controller
4124             }
4125             conn->state = SEND_CREATE_CONNECTION;
4126         }
4127         log_info("conn state %u", conn->state);
4128         switch (conn->state){
4129             // if connection active exists
4130             case OPEN:
4131                 // and OPEN, emit connection complete command
4132                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4133                 return -1; // packet not sent to controller
4134             case RECEIVED_DISCONNECTION_COMPLETE:
4135                 // create connection triggered in disconnect complete event, let's do it now
4136                 break;
4137             case SEND_CREATE_CONNECTION:
4138                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4139                 break;
4140             default:
4141                 // otherwise, just ignore as it is already in the open process
4142                 return -1; // packet not sent to controller
4143         }
4144         conn->state = SENT_CREATE_CONNECTION;
4145 
4146         // track outgoing connection
4147         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4148         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4149     }
4150 
4151     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4152         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4153     }
4154     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4155         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4156     }
4157 
4158     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4159         if (hci_stack->link_key_db){
4160             reverse_bd_addr(&packet[3], addr);
4161             hci_stack->link_key_db->delete_link_key(addr);
4162         }
4163     }
4164 
4165     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4166     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4167         reverse_bd_addr(&packet[3], addr);
4168         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4169         if (conn){
4170             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4171         }
4172     }
4173 
4174     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4175     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4176     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4177     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4178         reverse_bd_addr(&packet[3], addr);
4179         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4180         if (conn){
4181             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4182         }
4183     }
4184 
4185 #ifdef ENABLE_SCO_OVER_HCI
4186     // setup_synchronous_connection? Voice setting at offset 22
4187     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4188         // TODO: compare to current setting if sco connection already active
4189         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4190     }
4191     // accept_synchronus_connection? Voice setting at offset 18
4192     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4193         // TODO: compare to current setting if sco connection already active
4194         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4195     }
4196 #endif
4197 #endif
4198 
4199 #ifdef ENABLE_BLE
4200     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4201         hci_stack->le_random_address_set = 1;
4202         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4203     }
4204 #ifdef ENABLE_LE_PERIPHERAL
4205     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4206         hci_stack->le_advertisements_active = packet[3];
4207     }
4208 #endif
4209 #ifdef ENABLE_LE_CENTRAL
4210     else if (IS_COMMAND(packet, hci_le_create_connection)){
4211         // white list used?
4212         uint8_t initiator_filter_policy = packet[7];
4213         switch (initiator_filter_policy){
4214             case 0:
4215                 // whitelist not used
4216                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4217                 break;
4218             case 1:
4219                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4220                 break;
4221             default:
4222                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4223                 break;
4224         }
4225     }
4226     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4227         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4228     }
4229 #endif
4230 #endif
4231 
4232     hci_stack->num_cmd_packets--;
4233 
4234     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4235     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4236 }
4237 
4238 // disconnect because of security block
4239 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4240     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4241     if (!connection) return;
4242     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4243 }
4244 
4245 
4246 // Configure Secure Simple Pairing
4247 
4248 #ifdef ENABLE_CLASSIC
4249 
4250 // enable will enable SSP during init
4251 void gap_ssp_set_enable(int enable){
4252     hci_stack->ssp_enable = enable;
4253 }
4254 
4255 static int hci_local_ssp_activated(void){
4256     return gap_ssp_supported() && hci_stack->ssp_enable;
4257 }
4258 
4259 // if set, BTstack will respond to io capability request using authentication requirement
4260 void gap_ssp_set_io_capability(int io_capability){
4261     hci_stack->ssp_io_capability = io_capability;
4262 }
4263 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4264     hci_stack->ssp_authentication_requirement = authentication_requirement;
4265 }
4266 
4267 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4268 void gap_ssp_set_auto_accept(int auto_accept){
4269     hci_stack->ssp_auto_accept = auto_accept;
4270 }
4271 
4272 void gap_secure_connections_enable(bool enable){
4273     hci_stack->secure_connections_enable = enable;
4274 }
4275 
4276 #endif
4277 
4278 // va_list part of hci_send_cmd
4279 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4280     if (!hci_can_send_command_packet_now()){
4281         log_error("hci_send_cmd called but cannot send packet now");
4282         return 0;
4283     }
4284 
4285     // for HCI INITIALIZATION
4286     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4287     hci_stack->last_cmd_opcode = cmd->opcode;
4288 
4289     hci_reserve_packet_buffer();
4290     uint8_t * packet = hci_stack->hci_packet_buffer;
4291     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4292     int err = hci_send_cmd_packet(packet, size);
4293 
4294     // release packet buffer on error or for synchronous transport implementations
4295     if ((err < 0) || hci_transport_synchronous()){
4296         hci_release_packet_buffer();
4297         hci_emit_transport_packet_sent();
4298     }
4299 
4300     return err;
4301 }
4302 
4303 /**
4304  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4305  */
4306 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4307     va_list argptr;
4308     va_start(argptr, cmd);
4309     int res = hci_send_cmd_va_arg(cmd, argptr);
4310     va_end(argptr);
4311     return res;
4312 }
4313 
4314 // Create various non-HCI events.
4315 // TODO: generalize, use table similar to hci_create_command
4316 
4317 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4318     // dump packet
4319     if (dump) {
4320         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4321     }
4322 
4323     // dispatch to all event handlers
4324     btstack_linked_list_iterator_t it;
4325     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4326     while (btstack_linked_list_iterator_has_next(&it)){
4327         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4328         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4329     }
4330 }
4331 
4332 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4333     if (!hci_stack->acl_packet_handler) return;
4334     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4335 }
4336 
4337 #ifdef ENABLE_CLASSIC
4338 static void hci_notify_if_sco_can_send_now(void){
4339     // notify SCO sender if waiting
4340     if (!hci_stack->sco_waiting_for_can_send_now) return;
4341     if (hci_can_send_sco_packet_now()){
4342         hci_stack->sco_waiting_for_can_send_now = 0;
4343         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4344         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4345         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4346     }
4347 }
4348 
4349 // parsing end emitting has been merged to reduce code size
4350 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4351     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4352 
4353     uint8_t * eir_data;
4354     ad_context_t context;
4355     const uint8_t * name;
4356     uint8_t         name_len;
4357 
4358     if (size < 3) return;
4359 
4360     int event_type = hci_event_packet_get_type(packet);
4361     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4362     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4363 
4364     switch (event_type){
4365         case HCI_EVENT_INQUIRY_RESULT:
4366         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4367             if (size != (3 + (num_responses * 14))) return;
4368             break;
4369         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4370             if (size != 257) return;
4371             if (num_responses != 1) return;
4372             break;
4373         default:
4374             return;
4375     }
4376 
4377     // event[1] is set at the end
4378     int i;
4379     for (i=0; i<num_responses;i++){
4380         memset(event, 0, sizeof(event));
4381         event[0] = GAP_EVENT_INQUIRY_RESULT;
4382         uint8_t event_size = 18;    // if name is not set by EIR
4383 
4384         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4385         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4386         (void)memcpy(&event[9],
4387                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4388                      3); // class of device
4389         (void)memcpy(&event[12],
4390                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4391                      2); // clock offset
4392 
4393         switch (event_type){
4394             case HCI_EVENT_INQUIRY_RESULT:
4395                 // 14,15,16,17 = 0, size 18
4396                 break;
4397             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4398                 event[14] = 1;
4399                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4400                 // 16,17 = 0, size 18
4401                 break;
4402             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4403                 event[14] = 1;
4404                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4405                 // EIR packets only contain a single inquiry response
4406                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4407                 name = NULL;
4408                 // Iterate over EIR data
4409                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4410                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4411                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4412                     const uint8_t * data = ad_iterator_get_data(&context);
4413                     // Prefer Complete Local Name over Shortend Local Name
4414                     switch (data_type){
4415                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4416                             if (name) continue;
4417                             /* fall through */
4418                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4419                             name = data;
4420                             name_len = data_size;
4421                             break;
4422                         default:
4423                             break;
4424                     }
4425                 }
4426                 if (name){
4427                     event[16] = 1;
4428                     // truncate name if needed
4429                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4430                     event[17] = len;
4431                     (void)memcpy(&event[18], name, len);
4432                     event_size += len;
4433                 }
4434                 break;
4435         }
4436         event[1] = event_size - 2;
4437         hci_emit_event(event, event_size, 1);
4438     }
4439 }
4440 #endif
4441 
4442 void hci_emit_state(void){
4443     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4444     uint8_t event[3];
4445     event[0] = BTSTACK_EVENT_STATE;
4446     event[1] = sizeof(event) - 2;
4447     event[2] = hci_stack->state;
4448     hci_emit_event(event, sizeof(event), 1);
4449 }
4450 
4451 #ifdef ENABLE_CLASSIC
4452 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4453     uint8_t event[13];
4454     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4455     event[1] = sizeof(event) - 2;
4456     event[2] = status;
4457     little_endian_store_16(event, 3, con_handle);
4458     reverse_bd_addr(address, &event[5]);
4459     event[11] = 1; // ACL connection
4460     event[12] = 0; // encryption disabled
4461     hci_emit_event(event, sizeof(event), 1);
4462 }
4463 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4464     if (disable_l2cap_timeouts) return;
4465     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4466     uint8_t event[4];
4467     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4468     event[1] = sizeof(event) - 2;
4469     little_endian_store_16(event, 2, conn->con_handle);
4470     hci_emit_event(event, sizeof(event), 1);
4471 }
4472 #endif
4473 
4474 #ifdef ENABLE_BLE
4475 #ifdef ENABLE_LE_CENTRAL
4476 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4477     uint8_t event[21];
4478     event[0] = HCI_EVENT_LE_META;
4479     event[1] = sizeof(event) - 2;
4480     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4481     event[3] = status;
4482     little_endian_store_16(event, 4, con_handle);
4483     event[6] = 0; // TODO: role
4484     event[7] = address_type;
4485     reverse_bd_addr(address, &event[8]);
4486     little_endian_store_16(event, 14, 0); // interval
4487     little_endian_store_16(event, 16, 0); // latency
4488     little_endian_store_16(event, 18, 0); // supervision timeout
4489     event[20] = 0; // master clock accuracy
4490     hci_emit_event(event, sizeof(event), 1);
4491 }
4492 #endif
4493 #endif
4494 
4495 static void hci_emit_transport_packet_sent(void){
4496     // notify upper stack that it might be possible to send again
4497     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4498     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4499 }
4500 
4501 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4502     uint8_t event[6];
4503     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4504     event[1] = sizeof(event) - 2;
4505     event[2] = 0; // status = OK
4506     little_endian_store_16(event, 3, con_handle);
4507     event[5] = reason;
4508     hci_emit_event(event, sizeof(event), 1);
4509 }
4510 
4511 static void hci_emit_nr_connections_changed(void){
4512     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4513     uint8_t event[3];
4514     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4515     event[1] = sizeof(event) - 2;
4516     event[2] = nr_hci_connections();
4517     hci_emit_event(event, sizeof(event), 1);
4518 }
4519 
4520 static void hci_emit_hci_open_failed(void){
4521     log_info("BTSTACK_EVENT_POWERON_FAILED");
4522     uint8_t event[2];
4523     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4524     event[1] = sizeof(event) - 2;
4525     hci_emit_event(event, sizeof(event), 1);
4526 }
4527 
4528 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4529     log_info("hci_emit_dedicated_bonding_result %u ", status);
4530     uint8_t event[9];
4531     int pos = 0;
4532     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4533     event[pos++] = sizeof(event) - 2;
4534     event[pos++] = status;
4535     reverse_bd_addr(address, &event[pos]);
4536     hci_emit_event(event, sizeof(event), 1);
4537 }
4538 
4539 
4540 #ifdef ENABLE_CLASSIC
4541 
4542 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4543     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4544     uint8_t event[5];
4545     int pos = 0;
4546     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4547     event[pos++] = sizeof(event) - 2;
4548     little_endian_store_16(event, 2, con_handle);
4549     pos += 2;
4550     event[pos++] = level;
4551     hci_emit_event(event, sizeof(event), 1);
4552 }
4553 
4554 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4555     if (!connection) return LEVEL_0;
4556     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4557     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4558     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4559     // LEVEL 4 always requires 128 bit encrytion key size
4560     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4561         security_level = LEVEL_3;
4562     }
4563     return security_level;
4564 }
4565 
4566 static void hci_emit_discoverable_enabled(uint8_t enabled){
4567     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4568     uint8_t event[3];
4569     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4570     event[1] = sizeof(event) - 2;
4571     event[2] = enabled;
4572     hci_emit_event(event, sizeof(event), 1);
4573 }
4574 
4575 // query if remote side supports eSCO
4576 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4577     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4578     if (!connection) return 0;
4579     return (connection->remote_supported_features[0] & 1) != 0;
4580 }
4581 
4582 static bool hci_ssp_supported(hci_connection_t * connection){
4583     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4584     return (connection->bonding_flags & mask) == mask;
4585 }
4586 
4587 // query if remote side supports SSP
4588 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4589     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4590     if (!connection) return 0;
4591     return hci_ssp_supported(connection) ? 1 : 0;
4592 }
4593 
4594 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4595     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4596 }
4597 
4598 // GAP API
4599 /**
4600  * @bbrief enable/disable bonding. default is enabled
4601  * @praram enabled
4602  */
4603 void gap_set_bondable_mode(int enable){
4604     hci_stack->bondable = enable ? 1 : 0;
4605 }
4606 /**
4607  * @brief Get bondable mode.
4608  * @return 1 if bondable
4609  */
4610 int gap_get_bondable_mode(void){
4611     return hci_stack->bondable;
4612 }
4613 
4614 /**
4615  * @brief map link keys to security levels
4616  */
4617 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4618     switch (link_key_type){
4619         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4620             return LEVEL_4;
4621         case COMBINATION_KEY:
4622         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4623             return LEVEL_3;
4624         default:
4625             return LEVEL_2;
4626     }
4627 }
4628 
4629 /**
4630  * @brief map link keys to secure connection yes/no
4631  */
4632 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4633     switch (link_key_type){
4634         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4635         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4636             return 1;
4637         default:
4638             return 0;
4639     }
4640 }
4641 
4642 /**
4643  * @brief map link keys to authenticated
4644  */
4645 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4646     switch (link_key_type){
4647         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4648         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4649             return 1;
4650         default:
4651             return 0;
4652     }
4653 }
4654 
4655 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4656     log_info("gap_mitm_protection_required_for_security_level %u", level);
4657     return level > LEVEL_2;
4658 }
4659 
4660 /**
4661  * @brief get current security level
4662  */
4663 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4664     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4665     if (!connection) return LEVEL_0;
4666     return gap_security_level_for_connection(connection);
4667 }
4668 
4669 /**
4670  * @brief request connection to device to
4671  * @result GAP_AUTHENTICATION_RESULT
4672  */
4673 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4674     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4675     if (!connection){
4676         hci_emit_security_level(con_handle, LEVEL_0);
4677         return;
4678     }
4679     gap_security_level_t current_level = gap_security_level(con_handle);
4680     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4681         requested_level, connection->requested_security_level, current_level);
4682 
4683     // assumption: earlier requested security higher than current level => security request is active
4684     if (current_level < connection->requested_security_level){
4685         if (connection->requested_security_level < requested_level){
4686             // increase requested level as new level is higher
4687 
4688             // TODO: handle re-authentication when done
4689 
4690             connection->requested_security_level = requested_level;
4691         }
4692         return;
4693     }
4694 
4695     // no request active, notify if security sufficient
4696     if (requested_level <= current_level){
4697         hci_emit_security_level(con_handle, current_level);
4698         return;
4699     }
4700 
4701     // start pairing to increase security level
4702     connection->requested_security_level = requested_level;
4703 
4704 #if 0
4705     // sending encryption request without a link key results in an error.
4706     // TODO: figure out how to use it properly
4707 
4708     // would enabling ecnryption suffice (>= LEVEL_2)?
4709     if (hci_stack->link_key_db){
4710         link_key_type_t link_key_type;
4711         link_key_t      link_key;
4712         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4713             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4714                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4715                 return;
4716             }
4717         }
4718     }
4719 #endif
4720 
4721     // start to authenticate connection
4722     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4723     hci_run();
4724 }
4725 
4726 /**
4727  * @brief start dedicated bonding with device. disconnect after bonding
4728  * @param device
4729  * @param request MITM protection
4730  * @result GAP_DEDICATED_BONDING_COMPLETE
4731  */
4732 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4733 
4734     // create connection state machine
4735     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4736 
4737     if (!connection){
4738         return BTSTACK_MEMORY_ALLOC_FAILED;
4739     }
4740 
4741     // delete linkn key
4742     gap_drop_link_key_for_bd_addr(device);
4743 
4744     // configure LEVEL_2/3, dedicated bonding
4745     connection->state = SEND_CREATE_CONNECTION;
4746     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4747     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4748     connection->bonding_flags = BONDING_DEDICATED;
4749 
4750     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4751 
4752     // handle: connnection failure (connection complete != ok)
4753     // handle: authentication failure
4754     // handle: disconnect on done
4755 
4756     hci_run();
4757 
4758     return 0;
4759 }
4760 #endif
4761 
4762 void gap_set_local_name(const char * local_name){
4763     hci_stack->local_name = local_name;
4764 }
4765 
4766 
4767 #ifdef ENABLE_BLE
4768 
4769 #ifdef ENABLE_LE_CENTRAL
4770 void gap_start_scan(void){
4771     hci_stack->le_scanning_enabled = 1;
4772     hci_run();
4773 }
4774 
4775 void gap_stop_scan(void){
4776     hci_stack->le_scanning_enabled = 0;
4777     hci_run();
4778 }
4779 
4780 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4781     hci_stack->le_scan_type     = scan_type;
4782     hci_stack->le_scan_interval = scan_interval;
4783     hci_stack->le_scan_window   = scan_window;
4784     hci_run();
4785 }
4786 
4787 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4788     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4789     if (!conn){
4790         log_info("gap_connect: no connection exists yet, creating context");
4791         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4792         if (!conn){
4793             // notify client that alloc failed
4794             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4795             log_info("gap_connect: failed to alloc hci_connection_t");
4796             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4797         }
4798         conn->state = SEND_CREATE_CONNECTION;
4799         log_info("gap_connect: send create connection next");
4800         hci_run();
4801         return ERROR_CODE_SUCCESS;
4802     }
4803 
4804     if (!hci_is_le_connection(conn) ||
4805         (conn->state == SEND_CREATE_CONNECTION) ||
4806         (conn->state == SENT_CREATE_CONNECTION)) {
4807         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4808         log_error("gap_connect: classic connection or connect is already being created");
4809         return GATT_CLIENT_IN_WRONG_STATE;
4810     }
4811 
4812     // check if connection was just disconnected
4813     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4814         log_info("gap_connect: send create connection (again)");
4815         conn->state = SEND_CREATE_CONNECTION;
4816         hci_run();
4817         return ERROR_CODE_SUCCESS;
4818     }
4819 
4820     log_info("gap_connect: context exists with state %u", conn->state);
4821     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4822     hci_run();
4823     return ERROR_CODE_SUCCESS;
4824 }
4825 
4826 // @assumption: only a single outgoing LE Connection exists
4827 static hci_connection_t * gap_get_outgoing_connection(void){
4828     btstack_linked_item_t *it;
4829     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4830         hci_connection_t * conn = (hci_connection_t *) it;
4831         if (!hci_is_le_connection(conn)) continue;
4832         switch (conn->state){
4833             case SEND_CREATE_CONNECTION:
4834             case SENT_CREATE_CONNECTION:
4835             case SENT_CANCEL_CONNECTION:
4836                 return conn;
4837             default:
4838                 break;
4839         };
4840     }
4841     return NULL;
4842 }
4843 
4844 uint8_t gap_connect_cancel(void){
4845     hci_connection_t * conn = gap_get_outgoing_connection();
4846     if (!conn) return 0;
4847     switch (conn->state){
4848         case SEND_CREATE_CONNECTION:
4849             // skip sending create connection and emit event instead
4850             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4851             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4852             btstack_memory_hci_connection_free( conn );
4853             break;
4854         case SENT_CREATE_CONNECTION:
4855             // request to send cancel connection
4856             conn->state = SEND_CANCEL_CONNECTION;
4857             hci_run();
4858             break;
4859         default:
4860             break;
4861     }
4862     return 0;
4863 }
4864 #endif
4865 
4866 #ifdef ENABLE_LE_CENTRAL
4867 /**
4868  * @brief Set connection parameters for outgoing connections
4869  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4870  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4871  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4872  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4873  * @param conn_latency, default: 4
4874  * @param supervision_timeout (unit: 10ms), default: 720 ms
4875  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4876  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4877  */
4878 
4879 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4880     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4881     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4882     hci_stack->le_connection_scan_interval = conn_scan_interval;
4883     hci_stack->le_connection_scan_window = conn_scan_window;
4884     hci_stack->le_connection_interval_min = conn_interval_min;
4885     hci_stack->le_connection_interval_max = conn_interval_max;
4886     hci_stack->le_connection_latency = conn_latency;
4887     hci_stack->le_supervision_timeout = supervision_timeout;
4888     hci_stack->le_minimum_ce_length = min_ce_length;
4889     hci_stack->le_maximum_ce_length = max_ce_length;
4890 }
4891 #endif
4892 
4893 /**
4894  * @brief Updates the connection parameters for a given LE connection
4895  * @param handle
4896  * @param conn_interval_min (unit: 1.25ms)
4897  * @param conn_interval_max (unit: 1.25ms)
4898  * @param conn_latency
4899  * @param supervision_timeout (unit: 10ms)
4900  * @returns 0 if ok
4901  */
4902 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4903     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4904     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4905     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4906     connection->le_conn_interval_min = conn_interval_min;
4907     connection->le_conn_interval_max = conn_interval_max;
4908     connection->le_conn_latency = conn_latency;
4909     connection->le_supervision_timeout = supervision_timeout;
4910     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4911     hci_run();
4912     return 0;
4913 }
4914 
4915 /**
4916  * @brief Request an update of the connection parameter for a given LE connection
4917  * @param handle
4918  * @param conn_interval_min (unit: 1.25ms)
4919  * @param conn_interval_max (unit: 1.25ms)
4920  * @param conn_latency
4921  * @param supervision_timeout (unit: 10ms)
4922  * @returns 0 if ok
4923  */
4924 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4925     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4926     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4927     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4928     connection->le_conn_interval_min = conn_interval_min;
4929     connection->le_conn_interval_max = conn_interval_max;
4930     connection->le_conn_latency = conn_latency;
4931     connection->le_supervision_timeout = supervision_timeout;
4932     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4933     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4934     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4935     return 0;
4936 }
4937 
4938 #ifdef ENABLE_LE_PERIPHERAL
4939 
4940 static void gap_advertisments_changed(void){
4941     // disable advertisements before updating adv, scan data, or adv params
4942     if (hci_stack->le_advertisements_active){
4943         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4944     }
4945     hci_run();
4946 }
4947 
4948 /**
4949  * @brief Set Advertisement Data
4950  * @param advertising_data_length
4951  * @param advertising_data (max 31 octets)
4952  * @note data is not copied, pointer has to stay valid
4953  */
4954 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4955     hci_stack->le_advertisements_data_len = advertising_data_length;
4956     hci_stack->le_advertisements_data = advertising_data;
4957     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4958     gap_advertisments_changed();
4959 }
4960 
4961 /**
4962  * @brief Set Scan Response Data
4963  * @param advertising_data_length
4964  * @param advertising_data (max 31 octets)
4965  * @note data is not copied, pointer has to stay valid
4966  */
4967 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4968     hci_stack->le_scan_response_data_len = scan_response_data_length;
4969     hci_stack->le_scan_response_data = scan_response_data;
4970     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4971     gap_advertisments_changed();
4972 }
4973 
4974 /**
4975  * @brief Set Advertisement Parameters
4976  * @param adv_int_min
4977  * @param adv_int_max
4978  * @param adv_type
4979  * @param direct_address_type
4980  * @param direct_address
4981  * @param channel_map
4982  * @param filter_policy
4983  *
4984  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4985  */
4986  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4987     uint8_t direct_address_typ, bd_addr_t direct_address,
4988     uint8_t channel_map, uint8_t filter_policy) {
4989 
4990     hci_stack->le_advertisements_interval_min = adv_int_min;
4991     hci_stack->le_advertisements_interval_max = adv_int_max;
4992     hci_stack->le_advertisements_type = adv_type;
4993     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4994     hci_stack->le_advertisements_channel_map = channel_map;
4995     hci_stack->le_advertisements_filter_policy = filter_policy;
4996     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
4997                  6);
4998 
4999     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5000     gap_advertisments_changed();
5001  }
5002 
5003 /**
5004  * @brief Enable/Disable Advertisements
5005  * @param enabled
5006  */
5007 void gap_advertisements_enable(int enabled){
5008     hci_stack->le_advertisements_enabled = enabled;
5009     if (enabled && !hci_stack->le_advertisements_active){
5010         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
5011     }
5012     if (!enabled && hci_stack->le_advertisements_active){
5013         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
5014     }
5015     hci_run();
5016 }
5017 
5018 #endif
5019 
5020 void hci_le_set_own_address_type(uint8_t own_address_type){
5021     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5022     if (own_address_type == hci_stack->le_own_addr_type) return;
5023     hci_stack->le_own_addr_type = own_address_type;
5024 
5025 #ifdef ENABLE_LE_PERIPHERAL
5026     // update advertisement parameters, too
5027     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5028     gap_advertisments_changed();
5029 #endif
5030 #ifdef ENABLE_LE_CENTRAL
5031     // note: we don't update scan parameters or modify ongoing connection attempts
5032 #endif
5033 }
5034 
5035 #endif
5036 
5037 uint8_t gap_disconnect(hci_con_handle_t handle){
5038     hci_connection_t * conn = hci_connection_for_handle(handle);
5039     if (!conn){
5040         hci_emit_disconnection_complete(handle, 0);
5041         return 0;
5042     }
5043     // ignore if already disconnected
5044     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5045         return 0;
5046     }
5047     conn->state = SEND_DISCONNECT;
5048     hci_run();
5049     return 0;
5050 }
5051 
5052 int gap_read_rssi(hci_con_handle_t con_handle){
5053     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5054     if (hci_connection == NULL) return 0;
5055     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5056     hci_run();
5057     return 1;
5058 }
5059 
5060 /**
5061  * @brief Get connection type
5062  * @param con_handle
5063  * @result connection_type
5064  */
5065 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5066     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5067     if (!conn) return GAP_CONNECTION_INVALID;
5068     switch (conn->address_type){
5069         case BD_ADDR_TYPE_LE_PUBLIC:
5070         case BD_ADDR_TYPE_LE_RANDOM:
5071             return GAP_CONNECTION_LE;
5072         case BD_ADDR_TYPE_SCO:
5073             return GAP_CONNECTION_SCO;
5074         case BD_ADDR_TYPE_ACL:
5075             return GAP_CONNECTION_ACL;
5076         default:
5077             return GAP_CONNECTION_INVALID;
5078     }
5079 }
5080 
5081 #ifdef ENABLE_BLE
5082 
5083 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){
5084     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5085     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5086 
5087     conn->le_phy_update_all_phys    = all_phys;
5088     conn->le_phy_update_tx_phys     = tx_phys;
5089     conn->le_phy_update_rx_phys     = rx_phys;
5090     conn->le_phy_update_phy_options = phy_options;
5091 
5092     hci_run();
5093 
5094     return 0;
5095 }
5096 
5097 #ifdef ENABLE_LE_CENTRAL
5098 /**
5099  * @brief Auto Connection Establishment - Start Connecting to device
5100  * @param address_typ
5101  * @param address
5102  * @returns 0 if ok
5103  */
5104 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5105     // check capacity
5106     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5107     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5108     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5109     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5110     entry->address_type = address_type;
5111     (void)memcpy(entry->address, address, 6);
5112     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5113     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5114     hci_run();
5115     return 0;
5116 }
5117 
5118 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5119     btstack_linked_list_iterator_t it;
5120     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5121     while (btstack_linked_list_iterator_has_next(&it)){
5122         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5123         if (entry->address_type != address_type) continue;
5124         if (memcmp(entry->address, address, 6) != 0) continue;
5125         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5126             // remove from controller if already present
5127             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5128             continue;
5129         }
5130         // direclty remove entry from whitelist
5131         btstack_linked_list_iterator_remove(&it);
5132         btstack_memory_whitelist_entry_free(entry);
5133     }
5134 }
5135 
5136 /**
5137  * @brief Auto Connection Establishment - Stop Connecting to device
5138  * @param address_typ
5139  * @param address
5140  * @returns 0 if ok
5141  */
5142 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5143     hci_remove_from_whitelist(address_type, address);
5144     hci_run();
5145     return 0;
5146 }
5147 
5148 /**
5149  * @brief Auto Connection Establishment - Stop everything
5150  * @note  Convenience function to stop all active auto connection attempts
5151  */
5152 void gap_auto_connection_stop_all(void){
5153     btstack_linked_list_iterator_t it;
5154     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5155     while (btstack_linked_list_iterator_has_next(&it)){
5156         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5157         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5158             // remove from controller if already present
5159             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5160             continue;
5161         }
5162         // directly remove entry from whitelist
5163         btstack_linked_list_iterator_remove(&it);
5164         btstack_memory_whitelist_entry_free(entry);
5165     }
5166     hci_run();
5167 }
5168 
5169 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5170     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5171     if (!conn) return 0;
5172     return conn->le_connection_interval;
5173 }
5174 #endif
5175 #endif
5176 
5177 #ifdef ENABLE_CLASSIC
5178 /**
5179  * @brief Set Extended Inquiry Response data
5180  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5181  * @note has to be done before stack starts up
5182  */
5183 void gap_set_extended_inquiry_response(const uint8_t * data){
5184     hci_stack->eir_data = data;
5185 }
5186 
5187 /**
5188  * @brief Start GAP Classic Inquiry
5189  * @param duration in 1.28s units
5190  * @return 0 if ok
5191  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5192  */
5193 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5194     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5195     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5196     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5197         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5198     }
5199     hci_stack->inquiry_state = duration_in_1280ms_units;
5200     hci_run();
5201     return 0;
5202 }
5203 
5204 /**
5205  * @brief Stop GAP Classic Inquiry
5206  * @returns 0 if ok
5207  */
5208 int gap_inquiry_stop(void){
5209     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5210         // emit inquiry complete event, before it even started
5211         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5212         hci_emit_event(event, sizeof(event), 1);
5213         return 0;
5214     }
5215     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5216     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5217     hci_run();
5218     return 0;
5219 }
5220 
5221 
5222 /**
5223  * @brief Remote Name Request
5224  * @param addr
5225  * @param page_scan_repetition_mode
5226  * @param clock_offset only used when bit 15 is set
5227  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5228  */
5229 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5230     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5231     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5232     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5233     hci_stack->remote_name_clock_offset = clock_offset;
5234     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5235     hci_run();
5236     return 0;
5237 }
5238 
5239 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5240     hci_stack->gap_pairing_state = state;
5241     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5242     hci_run();
5243     return 0;
5244 }
5245 
5246 /**
5247  * @brief Legacy Pairing Pin Code Response
5248  * @param addr
5249  * @param pin
5250  * @return 0 if ok
5251  */
5252 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5253     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5254     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5255     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5256 }
5257 
5258 /**
5259  * @brief Abort Legacy Pairing
5260  * @param addr
5261  * @param pin
5262  * @return 0 if ok
5263  */
5264 int gap_pin_code_negative(bd_addr_t addr){
5265     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5266     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5267 }
5268 
5269 /**
5270  * @brief SSP Passkey Response
5271  * @param addr
5272  * @param passkey
5273  * @return 0 if ok
5274  */
5275 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5276     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5277     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5278     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5279 }
5280 
5281 /**
5282  * @brief Abort SSP Passkey Entry/Pairing
5283  * @param addr
5284  * @param pin
5285  * @return 0 if ok
5286  */
5287 int gap_ssp_passkey_negative(bd_addr_t addr){
5288     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5289     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5290 }
5291 
5292 /**
5293  * @brief Accept SSP Numeric Comparison
5294  * @param addr
5295  * @param passkey
5296  * @return 0 if ok
5297  */
5298 int gap_ssp_confirmation_response(bd_addr_t addr){
5299     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5300     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5301 }
5302 
5303 /**
5304  * @brief Abort SSP Numeric Comparison/Pairing
5305  * @param addr
5306  * @param pin
5307  * @return 0 if ok
5308  */
5309 int gap_ssp_confirmation_negative(bd_addr_t addr){
5310     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5311     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5312 }
5313 
5314 /**
5315  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5316  * @param inquiry_mode see bluetooth_defines.h
5317  */
5318 void hci_set_inquiry_mode(inquiry_mode_t mode){
5319     hci_stack->inquiry_mode = mode;
5320 }
5321 
5322 /**
5323  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5324  */
5325 void hci_set_sco_voice_setting(uint16_t voice_setting){
5326     hci_stack->sco_voice_setting = voice_setting;
5327 }
5328 
5329 /**
5330  * @brief Get SCO Voice Setting
5331  * @return current voice setting
5332  */
5333 uint16_t hci_get_sco_voice_setting(void){
5334     return hci_stack->sco_voice_setting;
5335 }
5336 
5337 static int hci_have_usb_transport(void){
5338     if (!hci_stack->hci_transport) return 0;
5339     const char * transport_name = hci_stack->hci_transport->name;
5340     if (!transport_name) return 0;
5341     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5342 }
5343 
5344 /** @brief Get SCO packet length for current SCO Voice setting
5345  *  @note  Using SCO packets of the exact length is required for USB transfer
5346  *  @return Length of SCO packets in bytes (not audio frames)
5347  */
5348 int hci_get_sco_packet_length(void){
5349     int sco_packet_length = 0;
5350 
5351 #ifdef ENABLE_SCO_OVER_HCI
5352 
5353     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5354     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5355 
5356     if (hci_have_usb_transport()){
5357         // see Core Spec for H2 USB Transfer.
5358         // 3 byte SCO header + 24 bytes per connection
5359         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5360         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5361     } else {
5362         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5363         sco_packet_length = 3 + 60 * multiplier;
5364         // assert that it still fits inside an SCO buffer
5365         if (sco_packet_length > hci_stack->sco_data_packet_length){
5366             sco_packet_length = 3 + 60;
5367         }
5368     }
5369 #endif
5370     return sco_packet_length;
5371 }
5372 
5373 /**
5374 * @brief Sets the master/slave policy
5375 * @param policy (0: attempt to become master, 1: let connecting device decide)
5376 */
5377 void hci_set_master_slave_policy(uint8_t policy){
5378     hci_stack->master_slave_policy = policy;
5379 }
5380 
5381 #endif
5382 
5383 HCI_STATE hci_get_state(void){
5384     return hci_stack->state;
5385 }
5386 
5387 #ifdef ENABLE_CLASSIC
5388 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5389     hci_stack->gap_classic_accept_callback = accept_callback;
5390 }
5391 #endif
5392 
5393 /**
5394  * @brief Set callback for Bluetooth Hardware Error
5395  */
5396 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5397     hci_stack->hardware_error_callback = fn;
5398 }
5399 
5400 void hci_disconnect_all(void){
5401     btstack_linked_list_iterator_t it;
5402     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5403     while (btstack_linked_list_iterator_has_next(&it)){
5404         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5405         if (con->state == SENT_DISCONNECT) continue;
5406         con->state = SEND_DISCONNECT;
5407     }
5408     hci_run();
5409 }
5410 
5411 uint16_t hci_get_manufacturer(void){
5412     return hci_stack->manufacturer;
5413 }
5414 
5415 #ifdef ENABLE_BLE
5416 
5417 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5418     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5419     if (!hci_con) return NULL;
5420     return &hci_con->sm_connection;
5421 }
5422 
5423 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5424 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5425 
5426 int gap_encryption_key_size(hci_con_handle_t con_handle){
5427     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5428     if (hci_connection == NULL) return 0;
5429     if (hci_is_le_connection(hci_connection)){
5430         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5431         if (sm_conn->sm_connection_encrypted) {
5432             return sm_conn->sm_actual_encryption_key_size;
5433         }
5434     }
5435 #ifdef ENABLE_CLASSIC
5436     else {
5437         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5438             return hci_connection->encryption_key_size;
5439         }
5440     }
5441 #endif
5442     return 0;
5443 }
5444 
5445 int gap_authenticated(hci_con_handle_t con_handle){
5446     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5447     if (hci_connection == NULL) return 0;
5448 
5449     switch (hci_connection->address_type){
5450         case BD_ADDR_TYPE_LE_PUBLIC:
5451         case BD_ADDR_TYPE_LE_RANDOM:
5452             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5453             return hci_connection->sm_connection.sm_connection_authenticated;
5454 #ifdef ENABLE_CLASSIC
5455         case BD_ADDR_TYPE_SCO:
5456         case BD_ADDR_TYPE_ACL:
5457             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5458 #endif
5459         default:
5460             return 0;
5461     }
5462 }
5463 
5464 int gap_secure_connection(hci_con_handle_t con_handle){
5465     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5466     if (hci_connection == NULL) return 0;
5467 
5468     switch (hci_connection->address_type){
5469         case BD_ADDR_TYPE_LE_PUBLIC:
5470         case BD_ADDR_TYPE_LE_RANDOM:
5471             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5472             return hci_connection->sm_connection.sm_connection_sc;
5473 #ifdef ENABLE_CLASSIC
5474         case BD_ADDR_TYPE_SCO:
5475         case BD_ADDR_TYPE_ACL:
5476             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5477 #endif
5478         default:
5479             return 0;
5480     }
5481 }
5482 
5483 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5484     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5485     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5486     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5487     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5488     return sm_conn->sm_connection_authorization_state;
5489 }
5490 #endif
5491 
5492 #ifdef ENABLE_CLASSIC
5493 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){
5494     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5495     if (!conn) return GAP_CONNECTION_INVALID;
5496     conn->sniff_min_interval = sniff_min_interval;
5497     conn->sniff_max_interval = sniff_max_interval;
5498     conn->sniff_attempt = sniff_attempt;
5499     conn->sniff_timeout = sniff_timeout;
5500     hci_run();
5501     return 0;
5502 }
5503 
5504 /**
5505  * @brief Exit Sniff mode
5506  * @param con_handle
5507  @ @return 0 if ok
5508  */
5509 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5510     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5511     if (!conn) return GAP_CONNECTION_INVALID;
5512     conn->sniff_min_interval = 0xffff;
5513     hci_run();
5514     return 0;
5515 }
5516 #endif
5517 
5518 void hci_halting_defer(void){
5519     if (hci_stack->state != HCI_STATE_HALTING) return;
5520     switch (hci_stack->substate){
5521         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5522         case HCI_HALTING_CLOSE:
5523             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5524             break;
5525         default:
5526             break;
5527     }
5528 }
5529 
5530 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5531 void hci_setup_test_connections_fuzz(void){
5532     hci_connection_t * conn;
5533 
5534     // default address: 66:55:44:33:00:01
5535     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5536 
5537     // setup Controller info
5538     hci_stack->num_cmd_packets = 255;
5539     hci_stack->acl_packets_total_num = 255;
5540 
5541     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5542     addr[5] = 0x01;
5543     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5544     conn->con_handle = addr[5];
5545     conn->role  = HCI_ROLE_SLAVE;
5546     conn->state = RECEIVED_CONNECTION_REQUEST;
5547     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5548 
5549     // setup incoming Classic SCO connection with con handle 0x0002
5550     addr[5] = 0x02;
5551     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5552     conn->con_handle = addr[5];
5553     conn->role  = HCI_ROLE_SLAVE;
5554     conn->state = RECEIVED_CONNECTION_REQUEST;
5555     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5556 
5557     // setup ready Classic ACL connection with con handle 0x0003
5558     addr[5] = 0x03;
5559     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5560     conn->con_handle = addr[5];
5561     conn->role  = HCI_ROLE_SLAVE;
5562     conn->state = OPEN;
5563     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5564 
5565     // setup ready Classic SCO connection with con handle 0x0004
5566     addr[5] = 0x04;
5567     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5568     conn->con_handle = addr[5];
5569     conn->role  = HCI_ROLE_SLAVE;
5570     conn->state = OPEN;
5571     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5572 
5573     // setup ready LE ACL connection with con handle 0x005 and public address
5574     addr[5] = 0x05;
5575     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5576     conn->con_handle = addr[5];
5577     conn->role  = HCI_ROLE_SLAVE;
5578     conn->state = OPEN;
5579     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5580 }
5581 
5582 void hci_free_connections_fuzz(void){
5583     btstack_linked_list_iterator_t it;
5584     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5585     while (btstack_linked_list_iterator_has_next(&it)){
5586         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5587         btstack_linked_list_iterator_remove(&it);
5588         btstack_memory_hci_connection_free(con);
5589     }
5590 }
5591 void hci_simulate_working_fuzz(void){
5592     hci_init_done();
5593     hci_stack->num_cmd_packets = 255;
5594 }
5595 #endif
5596