xref: /btstack/src/hci.c (revision 67aae55197b5e3d998f4beab1abae10c98495871)
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_received(hci_connection_t * conn){
1910     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1911     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1912     if (conn->bonding_flags & BONDING_DEDICATED){
1913         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1914     }
1915 }
1916 
1917 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1918     // handle BT initialization
1919     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1920         hci_initializing_event_handler(packet, size);
1921     }
1922 
1923     // help with BT sleep
1924     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1925         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1926         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1927         hci_initializing_next_state();
1928     }
1929 }
1930 
1931 static void event_handler(uint8_t *packet, int size){
1932 
1933     uint16_t event_length = packet[1];
1934 
1935     // assert packet is complete
1936     if (size != (event_length + 2)){
1937         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1938         return;
1939     }
1940 
1941     bd_addr_t addr;
1942     bd_addr_type_t addr_type;
1943     hci_con_handle_t handle;
1944     hci_connection_t * conn;
1945     int i;
1946     int create_connection_cmd;
1947 
1948 #ifdef ENABLE_CLASSIC
1949     uint8_t link_type;
1950 #endif
1951 
1952     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1953 
1954     switch (hci_event_packet_get_type(packet)) {
1955 
1956         case HCI_EVENT_COMMAND_COMPLETE:
1957             // get num cmd packets - limit to 1 to reduce complexity
1958             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1959 
1960             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1961                 if (packet[5]) break;
1962                 // terminate, name 248 chars
1963                 packet[6+248] = 0;
1964                 log_info("local name: %s", &packet[6]);
1965             }
1966             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1967                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1968                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1969                     uint16_t acl_len = little_endian_read_16(packet, 6);
1970                     uint16_t sco_len = packet[8];
1971 
1972                     // determine usable ACL/SCO payload size
1973                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1974                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1975 
1976                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1977                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1978 
1979                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1980                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1981                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1982                 }
1983             }
1984             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
1985                 if (packet[5] == 0){
1986                     uint8_t event[5];
1987                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
1988                     event[1] = 3;
1989                     (void)memcpy(&event[2], &packet[6], 3);
1990                     hci_emit_event(event, sizeof(event), 1);
1991                 }
1992             }
1993 #ifdef ENABLE_BLE
1994             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1995                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1996                 hci_stack->le_acl_packets_total_num  = packet[8];
1997                 // determine usable ACL payload size
1998                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1999                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2000                 }
2001                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2002             }
2003 #endif
2004 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2005             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
2006                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2007                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2008                 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);
2009             }
2010 #endif
2011 #ifdef ENABLE_LE_CENTRAL
2012             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
2013                 hci_stack->le_whitelist_capacity = packet[6];
2014                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2015             }
2016 #endif
2017             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
2018                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2019 				hci_stack->local_bd_addr);
2020                 log_info("Local Address, Status: 0x%02x: Addr: %s",
2021                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2022 #ifdef ENABLE_CLASSIC
2023                 if (hci_stack->link_key_db){
2024                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2025                 }
2026 #endif
2027             }
2028 #ifdef ENABLE_CLASSIC
2029             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2030                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2031             }
2032             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2033                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2034                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2035                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2036                     hci_emit_event(event, sizeof(event), 1);
2037                 }
2038             }
2039 #endif
2040 
2041             // Note: HCI init checks
2042             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2043                 (void)memcpy(hci_stack->local_supported_features,
2044 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2045 			     8);
2046 
2047 #ifdef ENABLE_CLASSIC
2048                 // determine usable ACL packet types based on host buffer size and supported features
2049                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2050                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2051 #endif
2052                 // Classic/LE
2053                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2054             }
2055             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2056                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2057                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2058                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2059                 // map Cypress to Broadcom
2060                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2061                     log_info("Treat Cypress as Broadcom");
2062                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2063                     little_endian_store_16(packet, 10, manufacturer);
2064                 }
2065                 hci_stack->manufacturer = manufacturer;
2066                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2067                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2068                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2069             }
2070             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2071                 hci_stack->local_supported_commands[0] =
2072                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2073                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2074                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2075                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2076                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2077                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2078                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2079                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2080                 hci_stack->local_supported_commands[1] =
2081                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+ 2] & 0x40) >> 6) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2082                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+32] & 0x08) >> 2);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2083                 log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2084             }
2085 #ifdef ENABLE_CLASSIC
2086             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2087                 if (packet[5] == 0){
2088                     hci_stack->synchronous_flow_control_enabled = 1;
2089                 }
2090             }
2091             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2092                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2093                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2094                 conn   = hci_connection_for_handle(handle);
2095                 if (!conn) break;
2096                 if (status == 0){
2097                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2098                     log_info("Handle %x04x key Size: %u", handle, key_size);
2099                     conn->encryption_key_size = key_size;
2100                 } else {
2101                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2102                     conn->encryption_key_size = 1;
2103                 }
2104                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2105                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2106             }
2107 #endif
2108             break;
2109 
2110         case HCI_EVENT_COMMAND_STATUS:
2111             // get num cmd packets - limit to 1 to reduce complexity
2112             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2113 
2114             // check command status to detected failed outgoing connections
2115             create_connection_cmd = 0;
2116 #ifdef ENABLE_CLASSIC
2117             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2118                 create_connection_cmd = 1;
2119             }
2120 #endif
2121 #ifdef ENABLE_LE_CENTRAL
2122             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2123                 create_connection_cmd = 1;
2124             }
2125 #endif
2126             if (create_connection_cmd) {
2127                 uint8_t status = hci_event_command_status_get_status(packet);
2128                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2129                 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);
2130 
2131                 // reset outgoing address info
2132                 memset(hci_stack->outgoing_addr, 0, 6);
2133                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2134 
2135                 // error => outgoing connection failed
2136                 if ((conn != NULL) && (status != 0)){
2137                     hci_handle_connection_failed(conn, status);
2138                 }
2139             }
2140             break;
2141 
2142         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2143             if (size < 3) return;
2144             uint16_t num_handles = packet[2];
2145             if (size != (3 + num_handles * 4)) return;
2146             uint16_t offset = 3;
2147             for (i=0; i<num_handles;i++){
2148                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2149                 offset += 2;
2150                 uint16_t num_packets = little_endian_read_16(packet, offset);
2151                 offset += 2;
2152 
2153                 conn = hci_connection_for_handle(handle);
2154                 if (!conn){
2155                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2156                     continue;
2157                 }
2158 
2159                 if (conn->num_packets_sent >= num_packets){
2160                     conn->num_packets_sent -= num_packets;
2161                 } else {
2162                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2163                     conn->num_packets_sent = 0;
2164                 }
2165                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2166 
2167 #ifdef ENABLE_CLASSIC
2168                 // For SCO, we do the can_send_now_check here
2169                 hci_notify_if_sco_can_send_now();
2170 #endif
2171             }
2172             break;
2173         }
2174 
2175 #ifdef ENABLE_CLASSIC
2176         case HCI_EVENT_INQUIRY_COMPLETE:
2177             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2178                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2179                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2180                 hci_emit_event(event, sizeof(event), 1);
2181             }
2182             break;
2183         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2184             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2185                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2186             }
2187             break;
2188         case HCI_EVENT_CONNECTION_REQUEST:
2189             reverse_bd_addr(&packet[2], addr);
2190             if (hci_stack->gap_classic_accept_callback != NULL){
2191                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2192                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2193                     bd_addr_copy(hci_stack->decline_addr, addr);
2194                     break;
2195                 }
2196             }
2197 
2198             // TODO: eval COD 8-10
2199             link_type = packet[11];
2200             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2201             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2202             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2203             if (!conn) {
2204                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2205             }
2206             if (!conn) {
2207                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2208                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2209                 bd_addr_copy(hci_stack->decline_addr, addr);
2210                 break;
2211             }
2212             conn->role  = HCI_ROLE_SLAVE;
2213             conn->state = RECEIVED_CONNECTION_REQUEST;
2214             // store info about eSCO
2215             if (link_type == 0x02){
2216                 conn->remote_supported_features[0] |= 1;
2217             }
2218             hci_run();
2219             break;
2220 
2221         case HCI_EVENT_CONNECTION_COMPLETE:
2222             // Connection management
2223             reverse_bd_addr(&packet[5], addr);
2224             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2225             addr_type = BD_ADDR_TYPE_ACL;
2226             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2227             if (conn) {
2228                 if (!packet[2]){
2229                     conn->state = OPEN;
2230                     conn->con_handle = little_endian_read_16(packet, 3);
2231 
2232                     // queue get remote feature
2233                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2234 
2235                     // queue set supervision timeout if we're master
2236                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2237                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2238                     }
2239 
2240                     // restart timer
2241                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2242                     btstack_run_loop_add_timer(&conn->timeout);
2243 
2244                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2245 
2246                     hci_emit_nr_connections_changed();
2247                 } else {
2248                     // connection failed
2249                     hci_handle_connection_failed(conn, packet[2]);
2250                 }
2251             }
2252             break;
2253 
2254         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2255             reverse_bd_addr(&packet[5], addr);
2256             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2257             if (packet[2]){
2258                 // connection failed
2259                 break;
2260             }
2261             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2262             if (!conn) {
2263                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2264             }
2265             if (!conn) {
2266                 break;
2267             }
2268             conn->state = OPEN;
2269             conn->con_handle = little_endian_read_16(packet, 3);
2270 
2271 #ifdef ENABLE_SCO_OVER_HCI
2272             // update SCO
2273             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2274                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2275             }
2276             // trigger can send now
2277             if (hci_have_usb_transport()){
2278                 hci_stack->sco_can_send_now = 1;
2279             }
2280 #endif
2281             break;
2282 
2283         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2284             handle = little_endian_read_16(packet, 3);
2285             conn = hci_connection_for_handle(handle);
2286             if (!conn) break;
2287             if (!packet[2]){
2288                 uint8_t * features = &packet[5];
2289                 // SSP Controller
2290                 if (features[6] & (1 << 3)){
2291                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2292                 }
2293                 // eSCO
2294                 if (features[3] & (1<<7)){
2295                     conn->remote_supported_features[0] |= 1;
2296                 }
2297                 // Extended features
2298                 if (features[7] & (1<<7)){
2299                     conn->remote_supported_features[0] |= 2;
2300                 }
2301                 // read extended features if possible
2302                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2303                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2304                     break;
2305                 }
2306             }
2307             hci_handle_remote_features_received(conn);
2308             break;
2309 
2310         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2311             handle = little_endian_read_16(packet, 3);
2312             conn = hci_connection_for_handle(handle);
2313             if (!conn) break;
2314             // status = ok, page = 1
2315             if (!packet[2] && packet[5] == 1){
2316                 const uint8_t * features = &packet[7];
2317                 // SSP Host
2318                 if (features[0] & (1 << 0)){
2319                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2320                 }
2321             }
2322             hci_handle_remote_features_received(conn);
2323             break;
2324 
2325         case HCI_EVENT_LINK_KEY_REQUEST:
2326             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2327             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2328             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2329             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2330             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2331             hci_run();
2332             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2333             return;
2334 
2335         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2336             reverse_bd_addr(&packet[2], addr);
2337             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2338             if (!conn) break;
2339             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2340             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2341             // Change Connection Encryption keeps link key type
2342             if (link_key_type != CHANGED_COMBINATION_KEY){
2343                 conn->link_key_type = link_key_type;
2344             }
2345             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2346             // still forward event to allow dismiss of pairing dialog
2347             break;
2348         }
2349 
2350         case HCI_EVENT_PIN_CODE_REQUEST:
2351             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2352             // non-bondable mode: pin code negative reply will be sent
2353             if (!hci_stack->bondable){
2354                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2355                 hci_run();
2356                 return;
2357             }
2358             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2359             if (!hci_stack->link_key_db) break;
2360             hci_event_pin_code_request_get_bd_addr(packet, addr);
2361             hci_stack->link_key_db->delete_link_key(addr);
2362             break;
2363 
2364         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2365             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2366             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2367             break;
2368 
2369         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2370             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2371             if (!hci_stack->ssp_auto_accept) break;
2372             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2373             break;
2374 
2375         case HCI_EVENT_USER_PASSKEY_REQUEST:
2376             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2377             if (!hci_stack->ssp_auto_accept) break;
2378             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2379             break;
2380         case HCI_EVENT_MODE_CHANGE:
2381             handle = hci_event_mode_change_get_handle(packet);
2382             conn = hci_connection_for_handle(handle);
2383             if (!conn) break;
2384             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2385             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2386             break;
2387 #endif
2388 
2389         case HCI_EVENT_ENCRYPTION_CHANGE:
2390             handle = hci_event_encryption_change_get_connection_handle(packet);
2391             conn = hci_connection_for_handle(handle);
2392             if (!conn) break;
2393             if (hci_event_encryption_change_get_status(packet) == 0) {
2394                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2395                 if (encryption_enabled){
2396                     if (hci_is_le_connection(conn)){
2397                         // For LE, we accept connection as encrypted
2398                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2399                     }
2400 #ifdef ENABLE_CLASSIC
2401                     else {
2402                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2403                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2404                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2405                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2406                             log_info("SC during pairing, but only E0 now -> abort");
2407                             conn->state = conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2408                             break;
2409                         }
2410 
2411                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2412                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2413                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2414                         } else {
2415                             // if not, pretend everything is perfect
2416                             conn->encryption_key_size = 16;
2417                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2418                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2419                         }
2420                     }
2421 #endif
2422                 } else {
2423                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2424                 }
2425             }
2426 
2427             break;
2428 
2429 #ifdef ENABLE_CLASSIC
2430         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2431             handle = little_endian_read_16(packet, 3);
2432             conn = hci_connection_for_handle(handle);
2433             if (!conn) break;
2434 
2435             // dedicated bonding: send result and disconnect
2436             if (conn->bonding_flags & BONDING_DEDICATED){
2437                 conn->bonding_flags &= ~BONDING_DEDICATED;
2438                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2439                 conn->bonding_status = packet[2];
2440                 break;
2441             }
2442 
2443             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2444                 // link key sufficient for requested security
2445                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2446                 break;
2447             }
2448             // not enough
2449             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2450             break;
2451 #endif
2452 
2453         // HCI_EVENT_DISCONNECTION_COMPLETE
2454         // has been split, to first notify stack before shutting connection down
2455         // see end of function, too.
2456         case HCI_EVENT_DISCONNECTION_COMPLETE:
2457             if (packet[2]) break;   // status != 0
2458             handle = little_endian_read_16(packet, 3);
2459             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2460             if (hci_stack->acl_fragmentation_total_size > 0) {
2461                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2462                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2463                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2464                     hci_stack->acl_fragmentation_total_size = 0;
2465                     hci_stack->acl_fragmentation_pos = 0;
2466                     if (release_buffer){
2467                         hci_release_packet_buffer();
2468                     }
2469                 }
2470             }
2471 
2472             conn = hci_connection_for_handle(handle);
2473             if (!conn) break;
2474             // mark connection for shutdown
2475             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2476 
2477             // emit dedicatd bonding event
2478             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2479                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2480             }
2481 
2482 #ifdef ENABLE_BLE
2483 #ifdef ENABLE_LE_PERIPHERAL
2484             // re-enable advertisements for le connections if active
2485             if (hci_is_le_connection(conn)){
2486                 hci_reenable_advertisements_if_needed();
2487             }
2488 #endif
2489 #endif
2490             break;
2491 
2492         case HCI_EVENT_HARDWARE_ERROR:
2493             log_error("Hardware Error: 0x%02x", packet[2]);
2494             if (hci_stack->hardware_error_callback){
2495                 (*hci_stack->hardware_error_callback)(packet[2]);
2496             } else {
2497                 // if no special requests, just reboot stack
2498                 hci_power_control_off();
2499                 hci_power_control_on();
2500             }
2501             break;
2502 
2503 #ifdef ENABLE_CLASSIC
2504         case HCI_EVENT_ROLE_CHANGE:
2505             if (packet[2]) break;   // status != 0
2506             reverse_bd_addr(&packet[3], addr);
2507             addr_type = BD_ADDR_TYPE_ACL;
2508             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2509             if (!conn) break;
2510             conn->role = packet[9];
2511             break;
2512 #endif
2513 
2514         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2515             // release packet buffer only for asynchronous transport and if there are not further fragements
2516             if (hci_transport_synchronous()) {
2517                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2518                 return; // instead of break: to avoid re-entering hci_run()
2519             }
2520             hci_stack->acl_fragmentation_tx_active = 0;
2521             if (hci_stack->acl_fragmentation_total_size) break;
2522             hci_release_packet_buffer();
2523 
2524             // L2CAP receives this event via the hci_emit_event below
2525 
2526 #ifdef ENABLE_CLASSIC
2527             // For SCO, we do the can_send_now_check here
2528             hci_notify_if_sco_can_send_now();
2529 #endif
2530             break;
2531 
2532 #ifdef ENABLE_CLASSIC
2533         case HCI_EVENT_SCO_CAN_SEND_NOW:
2534             // For SCO, we do the can_send_now_check here
2535             hci_stack->sco_can_send_now = 1;
2536             hci_notify_if_sco_can_send_now();
2537             return;
2538 
2539         // explode inquriy results for easier consumption
2540         case HCI_EVENT_INQUIRY_RESULT:
2541         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2542         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2543             gap_inquiry_explode(packet, size);
2544             break;
2545 #endif
2546 
2547 #ifdef ENABLE_BLE
2548         case HCI_EVENT_LE_META:
2549             switch (packet[2]){
2550 #ifdef ENABLE_LE_CENTRAL
2551                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2552                     // log_info("advertising report received");
2553                     if (!hci_stack->le_scanning_enabled) break;
2554                     le_handle_advertisement_report(packet, size);
2555                     break;
2556 #endif
2557                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2558                     // Connection management
2559                     reverse_bd_addr(&packet[8], addr);
2560                     addr_type = (bd_addr_type_t)packet[7];
2561                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2562                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2563 
2564 #ifdef ENABLE_LE_CENTRAL
2565                     // if auto-connect, remove from whitelist in both roles
2566                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2567                         hci_remove_from_whitelist(addr_type, addr);
2568                     }
2569                     // handle error: error is reported only to the initiator -> outgoing connection
2570                     if (packet[3]){
2571 
2572                         // handle cancelled outgoing connection
2573                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2574                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2575                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2576                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2577                             conn = gap_get_outgoing_connection();
2578                         }
2579 
2580                         // outgoing connection establishment is done
2581                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2582                         // remove entry
2583                         if (conn){
2584                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2585                             btstack_memory_hci_connection_free( conn );
2586                         }
2587                         break;
2588                     }
2589 #endif
2590                     // on success, both hosts receive connection complete event
2591                     if (packet[6] == HCI_ROLE_MASTER){
2592 #ifdef ENABLE_LE_CENTRAL
2593                         // if we're master, it was an outgoing connection and we're done with it
2594                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2595 #endif
2596                     } else {
2597 #ifdef ENABLE_LE_PERIPHERAL
2598                         // if we're slave, it was an incoming connection, advertisements have stopped
2599                         hci_stack->le_advertisements_active = 0;
2600 #endif
2601                     }
2602                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2603                     if (!conn){
2604                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2605                     }
2606                     // no memory, sorry.
2607                     if (!conn){
2608                         break;
2609                     }
2610 
2611                     conn->state = OPEN;
2612                     conn->role  = packet[6];
2613                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2614                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2615 
2616 #ifdef ENABLE_LE_PERIPHERAL
2617                     if (packet[6] == HCI_ROLE_SLAVE){
2618                         hci_reenable_advertisements_if_needed();
2619                     }
2620 #endif
2621 
2622                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2623 
2624                     // restart timer
2625                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2626                     // btstack_run_loop_add_timer(&conn->timeout);
2627 
2628                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2629 
2630                     hci_emit_nr_connections_changed();
2631                     break;
2632 
2633                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2634                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2635                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2636                     conn = hci_connection_for_handle(handle);
2637                     if (!conn) break;
2638                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2639                     break;
2640 
2641                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2642                     // connection
2643                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2644                     conn = hci_connection_for_handle(handle);
2645                     if (conn) {
2646                         // read arguments
2647                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2648                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2649                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2650                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2651 
2652                         // validate against current connection parameter range
2653                         le_connection_parameter_range_t existing_range;
2654                         gap_get_connection_parameter_range(&existing_range);
2655                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2656                         if (update_parameter){
2657                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2658                             conn->le_conn_interval_min = le_conn_interval_min;
2659                             conn->le_conn_interval_max = le_conn_interval_max;
2660                             conn->le_conn_latency = le_conn_latency;
2661                             conn->le_supervision_timeout = le_supervision_timeout;
2662                         } else {
2663                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2664                         }
2665                     }
2666                     break;
2667 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2668                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2669                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2670                     conn = hci_connection_for_handle(handle);
2671                     if (conn) {
2672                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2673                     }
2674                     break;
2675 #endif
2676                 default:
2677                     break;
2678             }
2679             break;
2680 #endif
2681         case HCI_EVENT_VENDOR_SPECIFIC:
2682             // Vendor specific commands often create vendor specific event instead of num completed packets
2683             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2684             switch (hci_stack->manufacturer){
2685                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2686                     hci_stack->num_cmd_packets = 1;
2687                     break;
2688                 default:
2689                     break;
2690             }
2691             break;
2692         default:
2693             break;
2694     }
2695 
2696     handle_event_for_current_stack_state(packet, size);
2697 
2698     // notify upper stack
2699 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2700 
2701     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2702     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2703         if (!packet[2]){
2704             handle = little_endian_read_16(packet, 3);
2705             hci_connection_t * aConn = hci_connection_for_handle(handle);
2706             if (aConn) {
2707                 // discard connection if app did not trigger a reconnect in the event handler
2708                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2709                     hci_shutdown_connection(aConn);
2710                 }
2711             }
2712         }
2713     }
2714 
2715 	// execute main loop
2716 	hci_run();
2717 }
2718 
2719 #ifdef ENABLE_CLASSIC
2720 
2721 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2722 static void sco_schedule_tx(hci_connection_t * conn);
2723 
2724 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2725     log_debug("SCO TX Timeout");
2726     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2727     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2728     if (!conn) return;
2729 
2730     // trigger send
2731     conn->sco_tx_ready = 1;
2732     // extra packet if CVSD but SCO buffer is too short
2733     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2734         conn->sco_tx_ready++;
2735     }
2736     hci_notify_if_sco_can_send_now();
2737 }
2738 
2739 
2740 #define SCO_TX_AFTER_RX_MS (6)
2741 
2742 static void sco_schedule_tx(hci_connection_t * conn){
2743 
2744     uint32_t now = btstack_run_loop_get_time_ms();
2745     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2746     int time_delta_ms = sco_tx_ms - now;
2747 
2748     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2749 
2750     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2751     btstack_run_loop_set_timer(timer, time_delta_ms);
2752     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2753     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2754     btstack_run_loop_add_timer(timer);
2755 }
2756 
2757 static void sco_handler(uint8_t * packet, uint16_t size){
2758     // lookup connection struct
2759     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2760     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2761     if (!conn) return;
2762 
2763     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2764     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2765         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2766             packet[2] = 0x3c;
2767             memmove(&packet[3], &packet[23], 63);
2768             size = 63;
2769         }
2770     }
2771 
2772     if (hci_have_usb_transport()){
2773         // Nothing to do
2774     } else {
2775         // 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);
2776         if (hci_stack->synchronous_flow_control_enabled == 0){
2777             uint32_t now = btstack_run_loop_get_time_ms();
2778 
2779             if (!conn->sco_rx_valid){
2780                 // ignore first 10 packets
2781                 conn->sco_rx_count++;
2782                 // log_debug("sco rx count %u", conn->sco_rx_count);
2783                 if (conn->sco_rx_count == 10) {
2784                     // use first timestamp as is and pretent it just started
2785                     conn->sco_rx_ms = now;
2786                     conn->sco_rx_valid = 1;
2787                     conn->sco_rx_count = 0;
2788                     sco_schedule_tx(conn);
2789                 }
2790             } else {
2791                 // track expected arrival timme
2792                 conn->sco_rx_count++;
2793                 conn->sco_rx_ms += 7;
2794                 int delta = (int32_t) (now - conn->sco_rx_ms);
2795                 if (delta > 0){
2796                     conn->sco_rx_ms++;
2797                 }
2798                 // log_debug("sco rx %u", conn->sco_rx_ms);
2799                 sco_schedule_tx(conn);
2800             }
2801         }
2802     }
2803     // deliver to app
2804     if (hci_stack->sco_packet_handler) {
2805         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2806     }
2807 
2808 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2809     conn->num_packets_completed++;
2810     hci_stack->host_completed_packets = 1;
2811     hci_run();
2812 #endif
2813 }
2814 #endif
2815 
2816 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2817     hci_dump_packet(packet_type, 1, packet, size);
2818     switch (packet_type) {
2819         case HCI_EVENT_PACKET:
2820             event_handler(packet, size);
2821             break;
2822         case HCI_ACL_DATA_PACKET:
2823             acl_handler(packet, size);
2824             break;
2825 #ifdef ENABLE_CLASSIC
2826         case HCI_SCO_DATA_PACKET:
2827             sco_handler(packet, size);
2828             break;
2829 #endif
2830         default:
2831             break;
2832     }
2833 }
2834 
2835 /**
2836  * @brief Add event packet handler.
2837  */
2838 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2839     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2840 }
2841 
2842 
2843 /** Register HCI packet handlers */
2844 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2845     hci_stack->acl_packet_handler = handler;
2846 }
2847 
2848 #ifdef ENABLE_CLASSIC
2849 /**
2850  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2851  */
2852 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2853     hci_stack->sco_packet_handler = handler;
2854 }
2855 #endif
2856 
2857 static void hci_state_reset(void){
2858     // no connections yet
2859     hci_stack->connections = NULL;
2860 
2861     // keep discoverable/connectable as this has been requested by the client(s)
2862     // hci_stack->discoverable = 0;
2863     // hci_stack->connectable = 0;
2864     // hci_stack->bondable = 1;
2865     // hci_stack->own_addr_type = 0;
2866 
2867     // buffer is free
2868     hci_stack->hci_packet_buffer_reserved = 0;
2869 
2870     // no pending cmds
2871     hci_stack->decline_reason = 0;
2872     hci_stack->new_scan_enable_value = 0xff;
2873 
2874     // LE
2875 #ifdef ENABLE_BLE
2876     memset(hci_stack->le_random_address, 0, 6);
2877     hci_stack->le_random_address_set = 0;
2878 #endif
2879 #ifdef ENABLE_LE_CENTRAL
2880     hci_stack->le_scanning_active  = 0;
2881     hci_stack->le_scan_type = 0xff;
2882     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2883     hci_stack->le_whitelist = 0;
2884     hci_stack->le_whitelist_capacity = 0;
2885 #endif
2886 }
2887 
2888 #ifdef ENABLE_CLASSIC
2889 /**
2890  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2891  */
2892 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2893     // store and open remote device db
2894     hci_stack->link_key_db = link_key_db;
2895     if (hci_stack->link_key_db) {
2896         hci_stack->link_key_db->open();
2897     }
2898 }
2899 #endif
2900 
2901 void hci_init(const hci_transport_t *transport, const void *config){
2902 
2903 #ifdef HAVE_MALLOC
2904     if (!hci_stack) {
2905         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2906     }
2907 #else
2908     hci_stack = &hci_stack_static;
2909 #endif
2910     memset(hci_stack, 0, sizeof(hci_stack_t));
2911 
2912     // reference to use transport layer implementation
2913     hci_stack->hci_transport = transport;
2914 
2915     // reference to used config
2916     hci_stack->config = config;
2917 
2918     // setup pointer for outgoing packet buffer
2919     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2920 
2921     // max acl payload size defined in config.h
2922     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2923 
2924     // register packet handlers with transport
2925     transport->register_packet_handler(&packet_handler);
2926 
2927     hci_stack->state = HCI_STATE_OFF;
2928 
2929     // class of device
2930     hci_stack->class_of_device = 0x007a020c; // Smartphone
2931 
2932     // bondable by default
2933     hci_stack->bondable = 1;
2934 
2935 #ifdef ENABLE_CLASSIC
2936     // classic name
2937     hci_stack->local_name = default_classic_name;
2938 
2939     // Master slave policy
2940     hci_stack->master_slave_policy = 1;
2941 
2942     // Allow Role Switch
2943     hci_stack->allow_role_switch = 1;
2944 
2945     // Default / minimum security level = 2
2946     hci_stack->gap_security_level = LEVEL_2;
2947 
2948     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2949     hci_stack->gap_required_encyrption_key_size = 16;
2950 #endif
2951 
2952     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2953     hci_stack->ssp_enable = 1;
2954     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2955     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2956     hci_stack->ssp_auto_accept = 1;
2957 
2958     // Secure Connections: enable (requires support from Controller)
2959     hci_stack->secure_connections_enable = true;
2960 
2961     // voice setting - signed 16 bit pcm data with CVSD over the air
2962     hci_stack->sco_voice_setting = 0x60;
2963 
2964 #ifdef ENABLE_LE_CENTRAL
2965     // connection parameter to use for outgoing connections
2966     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2967     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2968     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2969     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2970     hci_stack->le_connection_latency      = 4;         // 4
2971     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2972     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2973     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2974 
2975     // default LE Scanning
2976     hci_stack->le_scan_interval = 0x1e0;
2977     hci_stack->le_scan_window   =  0x30;
2978 #endif
2979 
2980 #ifdef ENABLE_LE_PERIPHERAL
2981     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2982 #endif
2983 
2984     // connection parameter range used to answer connection parameter update requests in l2cap
2985     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2986     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2987     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2988     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2989     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2990     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2991 
2992     hci_state_reset();
2993 }
2994 
2995 /**
2996  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2997  */
2998 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2999     hci_stack->chipset = chipset_driver;
3000 
3001     // reset chipset driver - init is also called on power_up
3002     if (hci_stack->chipset && hci_stack->chipset->init){
3003         hci_stack->chipset->init(hci_stack->config);
3004     }
3005 }
3006 
3007 /**
3008  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3009  */
3010 void hci_set_control(const btstack_control_t *hardware_control){
3011     // references to used control implementation
3012     hci_stack->control = hardware_control;
3013     // init with transport config
3014     hardware_control->init(hci_stack->config);
3015 }
3016 
3017 void hci_close(void){
3018     // close remote device db
3019     if (hci_stack->link_key_db) {
3020         hci_stack->link_key_db->close();
3021     }
3022 
3023     btstack_linked_list_iterator_t lit;
3024     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3025     while (btstack_linked_list_iterator_has_next(&lit)){
3026         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3027         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3028         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3029         hci_shutdown_connection(connection);
3030     }
3031 
3032     hci_power_control(HCI_POWER_OFF);
3033 
3034 #ifdef HAVE_MALLOC
3035     free(hci_stack);
3036 #endif
3037     hci_stack = NULL;
3038 }
3039 
3040 #ifdef ENABLE_CLASSIC
3041 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3042     // validate ranage and set
3043     if (encryption_key_size < 7)  return;
3044     if (encryption_key_size > 16) return;
3045     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3046 }
3047 
3048 void gap_set_security_level(gap_security_level_t security_level){
3049     hci_stack->gap_security_level = security_level;
3050 }
3051 
3052 gap_security_level_t gap_get_security_level(void){
3053     return hci_stack->gap_security_level;
3054 }
3055 #endif
3056 
3057 #ifdef ENABLE_CLASSIC
3058 void gap_set_class_of_device(uint32_t class_of_device){
3059     hci_stack->class_of_device = class_of_device;
3060 }
3061 
3062 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3063     hci_stack->default_link_policy_settings = default_link_policy_settings;
3064 }
3065 
3066 void gap_set_allow_role_switch(bool allow_role_switch){
3067     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3068 }
3069 
3070 uint8_t hci_get_allow_role_switch(void){
3071     return  hci_stack->allow_role_switch;
3072 }
3073 
3074 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3075     hci_stack->link_supervision_timeout = link_supervision_timeout;
3076 }
3077 
3078 void hci_disable_l2cap_timeout_check(void){
3079     disable_l2cap_timeouts = 1;
3080 }
3081 #endif
3082 
3083 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3084 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3085 void hci_set_bd_addr(bd_addr_t addr){
3086     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3087     hci_stack->custom_bd_addr_set = 1;
3088 }
3089 #endif
3090 
3091 // State-Module-Driver overview
3092 // state                    module  low-level
3093 // HCI_STATE_OFF             off      close
3094 // HCI_STATE_INITIALIZING,   on       open
3095 // HCI_STATE_WORKING,        on       open
3096 // HCI_STATE_HALTING,        on       open
3097 // HCI_STATE_SLEEPING,    off/sleep   close
3098 // HCI_STATE_FALLING_ASLEEP  on       open
3099 
3100 static int hci_power_control_on(void){
3101 
3102     // power on
3103     int err = 0;
3104     if (hci_stack->control && hci_stack->control->on){
3105         err = (*hci_stack->control->on)();
3106     }
3107     if (err){
3108         log_error( "POWER_ON failed");
3109         hci_emit_hci_open_failed();
3110         return err;
3111     }
3112 
3113     // int chipset driver
3114     if (hci_stack->chipset && hci_stack->chipset->init){
3115         hci_stack->chipset->init(hci_stack->config);
3116     }
3117 
3118     // init transport
3119     if (hci_stack->hci_transport->init){
3120         hci_stack->hci_transport->init(hci_stack->config);
3121     }
3122 
3123     // open transport
3124     err = hci_stack->hci_transport->open();
3125     if (err){
3126         log_error( "HCI_INIT failed, turning Bluetooth off again");
3127         if (hci_stack->control && hci_stack->control->off){
3128             (*hci_stack->control->off)();
3129         }
3130         hci_emit_hci_open_failed();
3131         return err;
3132     }
3133     return 0;
3134 }
3135 
3136 static void hci_power_control_off(void){
3137 
3138     log_info("hci_power_control_off");
3139 
3140     // close low-level device
3141     hci_stack->hci_transport->close();
3142 
3143     log_info("hci_power_control_off - hci_transport closed");
3144 
3145     // power off
3146     if (hci_stack->control && hci_stack->control->off){
3147         (*hci_stack->control->off)();
3148     }
3149 
3150     log_info("hci_power_control_off - control closed");
3151 
3152     hci_stack->state = HCI_STATE_OFF;
3153 }
3154 
3155 static void hci_power_control_sleep(void){
3156 
3157     log_info("hci_power_control_sleep");
3158 
3159 #if 0
3160     // don't close serial port during sleep
3161 
3162     // close low-level device
3163     hci_stack->hci_transport->close(hci_stack->config);
3164 #endif
3165 
3166     // sleep mode
3167     if (hci_stack->control && hci_stack->control->sleep){
3168         (*hci_stack->control->sleep)();
3169     }
3170 
3171     hci_stack->state = HCI_STATE_SLEEPING;
3172 }
3173 
3174 static int hci_power_control_wake(void){
3175 
3176     log_info("hci_power_control_wake");
3177 
3178     // wake on
3179     if (hci_stack->control && hci_stack->control->wake){
3180         (*hci_stack->control->wake)();
3181     }
3182 
3183 #if 0
3184     // open low-level device
3185     int err = hci_stack->hci_transport->open(hci_stack->config);
3186     if (err){
3187         log_error( "HCI_INIT failed, turning Bluetooth off again");
3188         if (hci_stack->control && hci_stack->control->off){
3189             (*hci_stack->control->off)();
3190         }
3191         hci_emit_hci_open_failed();
3192         return err;
3193     }
3194 #endif
3195 
3196     return 0;
3197 }
3198 
3199 static void hci_power_transition_to_initializing(void){
3200     // set up state machine
3201     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3202     hci_stack->hci_packet_buffer_reserved = 0;
3203     hci_stack->state = HCI_STATE_INITIALIZING;
3204     hci_stack->substate = HCI_INIT_SEND_RESET;
3205 }
3206 
3207 int hci_power_control(HCI_POWER_MODE power_mode){
3208 
3209     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3210 
3211     int err = 0;
3212     switch (hci_stack->state){
3213 
3214         case HCI_STATE_OFF:
3215             switch (power_mode){
3216                 case HCI_POWER_ON:
3217                     err = hci_power_control_on();
3218                     if (err) {
3219                         log_error("hci_power_control_on() error %d", err);
3220                         return err;
3221                     }
3222                     hci_power_transition_to_initializing();
3223                     break;
3224                 case HCI_POWER_OFF:
3225                     // do nothing
3226                     break;
3227                 case HCI_POWER_SLEEP:
3228                     // do nothing (with SLEEP == OFF)
3229                     break;
3230             }
3231             break;
3232 
3233         case HCI_STATE_INITIALIZING:
3234             switch (power_mode){
3235                 case HCI_POWER_ON:
3236                     // do nothing
3237                     break;
3238                 case HCI_POWER_OFF:
3239                     // no connections yet, just turn it off
3240                     hci_power_control_off();
3241                     break;
3242                 case HCI_POWER_SLEEP:
3243                     // no connections yet, just turn it off
3244                     hci_power_control_sleep();
3245                     break;
3246             }
3247             break;
3248 
3249         case HCI_STATE_WORKING:
3250             switch (power_mode){
3251                 case HCI_POWER_ON:
3252                     // do nothing
3253                     break;
3254                 case HCI_POWER_OFF:
3255                     // see hci_run
3256                     hci_stack->state = HCI_STATE_HALTING;
3257                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3258                     break;
3259                 case HCI_POWER_SLEEP:
3260                     // see hci_run
3261                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3262                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3263                     break;
3264             }
3265             break;
3266 
3267         case HCI_STATE_HALTING:
3268             switch (power_mode){
3269                 case HCI_POWER_ON:
3270                     hci_power_transition_to_initializing();
3271                     break;
3272                 case HCI_POWER_OFF:
3273                     // do nothing
3274                     break;
3275                 case HCI_POWER_SLEEP:
3276                     // see hci_run
3277                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3278                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3279                     break;
3280             }
3281             break;
3282 
3283         case HCI_STATE_FALLING_ASLEEP:
3284             switch (power_mode){
3285                 case HCI_POWER_ON:
3286 
3287 #ifdef HAVE_PLATFORM_IPHONE_OS
3288                     // nothing to do, if H4 supports power management
3289                     if (btstack_control_iphone_power_management_enabled()){
3290                         hci_stack->state = HCI_STATE_INITIALIZING;
3291                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3292                         break;
3293                     }
3294 #endif
3295                     hci_power_transition_to_initializing();
3296                     break;
3297                 case HCI_POWER_OFF:
3298                     // see hci_run
3299                     hci_stack->state = HCI_STATE_HALTING;
3300                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3301                     break;
3302                 case HCI_POWER_SLEEP:
3303                     // do nothing
3304                     break;
3305             }
3306             break;
3307 
3308         case HCI_STATE_SLEEPING:
3309             switch (power_mode){
3310                 case HCI_POWER_ON:
3311 
3312 #ifdef HAVE_PLATFORM_IPHONE_OS
3313                     // nothing to do, if H4 supports power management
3314                     if (btstack_control_iphone_power_management_enabled()){
3315                         hci_stack->state = HCI_STATE_INITIALIZING;
3316                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3317                         hci_update_scan_enable();
3318                         break;
3319                     }
3320 #endif
3321                     err = hci_power_control_wake();
3322                     if (err) return err;
3323                     hci_power_transition_to_initializing();
3324                     break;
3325                 case HCI_POWER_OFF:
3326                     hci_stack->state = HCI_STATE_HALTING;
3327                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3328                     break;
3329                 case HCI_POWER_SLEEP:
3330                     // do nothing
3331                     break;
3332             }
3333             break;
3334     }
3335 
3336     // create internal event
3337 	hci_emit_state();
3338 
3339 	// trigger next/first action
3340 	hci_run();
3341 
3342     return 0;
3343 }
3344 
3345 
3346 #ifdef ENABLE_CLASSIC
3347 
3348 static void hci_update_scan_enable(void){
3349     // 2 = page scan, 1 = inq scan
3350     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3351     hci_run();
3352 }
3353 
3354 void gap_discoverable_control(uint8_t enable){
3355     if (enable) enable = 1; // normalize argument
3356 
3357     if (hci_stack->discoverable == enable){
3358         hci_emit_discoverable_enabled(hci_stack->discoverable);
3359         return;
3360     }
3361 
3362     hci_stack->discoverable = enable;
3363     hci_update_scan_enable();
3364 }
3365 
3366 void gap_connectable_control(uint8_t enable){
3367     if (enable) enable = 1; // normalize argument
3368 
3369     // don't emit event
3370     if (hci_stack->connectable == enable) return;
3371 
3372     hci_stack->connectable = enable;
3373     hci_update_scan_enable();
3374 }
3375 #endif
3376 
3377 void gap_local_bd_addr(bd_addr_t address_buffer){
3378     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3379 }
3380 
3381 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3382 static void hci_host_num_completed_packets(void){
3383 
3384     // create packet manually as arrays are not supported and num_commands should not get reduced
3385     hci_reserve_packet_buffer();
3386     uint8_t * packet = hci_get_outgoing_packet_buffer();
3387 
3388     uint16_t size = 0;
3389     uint16_t num_handles = 0;
3390     packet[size++] = 0x35;
3391     packet[size++] = 0x0c;
3392     size++;  // skip param len
3393     size++;  // skip num handles
3394 
3395     // add { handle, packets } entries
3396     btstack_linked_item_t * it;
3397     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3398         hci_connection_t * connection = (hci_connection_t *) it;
3399         if (connection->num_packets_completed){
3400             little_endian_store_16(packet, size, connection->con_handle);
3401             size += 2;
3402             little_endian_store_16(packet, size, connection->num_packets_completed);
3403             size += 2;
3404             //
3405             num_handles++;
3406             connection->num_packets_completed = 0;
3407         }
3408     }
3409 
3410     packet[2] = size - 3;
3411     packet[3] = num_handles;
3412 
3413     hci_stack->host_completed_packets = 0;
3414 
3415     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3416     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3417 
3418     // release packet buffer for synchronous transport implementations
3419     if (hci_transport_synchronous()){
3420         hci_release_packet_buffer();
3421         hci_emit_transport_packet_sent();
3422     }
3423 }
3424 #endif
3425 
3426 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3427     UNUSED(ds);
3428     hci_stack->substate = HCI_HALTING_CLOSE;
3429     // allow packet handlers to defer final shutdown
3430     hci_emit_state();
3431     hci_run();
3432 }
3433 
3434 static bool hci_run_acl_fragments(void){
3435     if (hci_stack->acl_fragmentation_total_size > 0) {
3436         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3437         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3438         if (connection) {
3439             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3440                 hci_send_acl_packet_fragments(connection);
3441                 return true;
3442             }
3443         } else {
3444             // connection gone -> discard further fragments
3445             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3446             hci_stack->acl_fragmentation_total_size = 0;
3447             hci_stack->acl_fragmentation_pos = 0;
3448         }
3449     }
3450     return false;
3451 }
3452 
3453 #ifdef ENABLE_CLASSIC
3454 static bool hci_run_general_gap_classic(void){
3455 
3456     // decline incoming connections
3457     if (hci_stack->decline_reason){
3458         uint8_t reason = hci_stack->decline_reason;
3459         hci_stack->decline_reason = 0;
3460         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3461         return true;
3462     }
3463     // send scan enable
3464     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3465         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3466         hci_stack->new_scan_enable_value = 0xff;
3467         return true;
3468     }
3469     // start/stop inquiry
3470     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3471         uint8_t duration = hci_stack->inquiry_state;
3472         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3473         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3474         return true;
3475     }
3476     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3477         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3478         hci_send_cmd(&hci_inquiry_cancel);
3479         return true;
3480     }
3481     // remote name request
3482     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3483         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3484         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3485                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3486         return true;
3487     }
3488     // pairing
3489     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3490         uint8_t state = hci_stack->gap_pairing_state;
3491         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3492         switch (state){
3493             case GAP_PAIRING_STATE_SEND_PIN:
3494                 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);
3495                 break;
3496             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3497                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3498                 break;
3499             case GAP_PAIRING_STATE_SEND_PASSKEY:
3500                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3501                 break;
3502             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3503                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3504                 break;
3505             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3506                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3507                 break;
3508             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3509                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3510                 break;
3511             default:
3512                 break;
3513         }
3514         return true;
3515     }
3516     return false;
3517 }
3518 #endif
3519 
3520 #ifdef ENABLE_BLE
3521 static bool hci_run_general_gap_le(void){
3522 
3523     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3524 
3525     if (hci_stack->state != HCI_STATE_WORKING) return false;
3526     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3527 
3528 #ifdef ENABLE_LE_CENTRAL
3529     // parameter change requires scanning to be stopped first
3530     if (hci_stack->le_scan_type != 0xff) {
3531         if (hci_stack->le_scanning_active){
3532             hci_stack->le_scanning_active = 0;
3533             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3534         } else {
3535             int scan_type = (int) hci_stack->le_scan_type;
3536             hci_stack->le_scan_type = 0xff;
3537             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);
3538         }
3539         return true;
3540     }
3541     // finally, we can enable/disable le scan
3542     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3543         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3544         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3545         return true;
3546     }
3547 #endif
3548 #ifdef ENABLE_LE_PERIPHERAL
3549     // le advertisement control
3550     if (hci_stack->le_advertisements_todo){
3551         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3552     }
3553     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3554         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3555         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3556         return true;
3557     }
3558     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3559         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3560         hci_send_cmd(&hci_le_set_advertising_parameters,
3561                      hci_stack->le_advertisements_interval_min,
3562                      hci_stack->le_advertisements_interval_max,
3563                      hci_stack->le_advertisements_type,
3564                      hci_stack->le_own_addr_type,
3565                      hci_stack->le_advertisements_direct_address_type,
3566                      hci_stack->le_advertisements_direct_address,
3567                      hci_stack->le_advertisements_channel_map,
3568                      hci_stack->le_advertisements_filter_policy);
3569         return true;
3570     }
3571     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3572         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3573         uint8_t adv_data_clean[31];
3574         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3575         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3576                      hci_stack->le_advertisements_data_len);
3577         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3578         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3579         return true;
3580     }
3581     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3582         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3583         uint8_t scan_data_clean[31];
3584         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3585         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3586                      hci_stack->le_scan_response_data_len);
3587         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3588         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3589         return true;
3590     }
3591     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3592         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3593         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3594         return true;
3595     }
3596 #endif
3597 
3598 #ifdef ENABLE_LE_CENTRAL
3599     //
3600     // LE Whitelist Management
3601     //
3602 
3603     // check if whitelist needs modification
3604     btstack_linked_list_iterator_t lit;
3605     int modification_pending = 0;
3606     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3607     while (btstack_linked_list_iterator_has_next(&lit)){
3608         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3609         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3610             modification_pending = 1;
3611             break;
3612         }
3613     }
3614 
3615     if (modification_pending){
3616         // stop connnecting if modification pending
3617         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3618             hci_send_cmd(&hci_le_create_connection_cancel);
3619             return true;
3620         }
3621 
3622         // add/remove entries
3623         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3624         while (btstack_linked_list_iterator_has_next(&lit)){
3625             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3626             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3627                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3628                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3629                 return true;
3630             }
3631             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3632                 bd_addr_t address;
3633                 bd_addr_type_t address_type = entry->address_type;
3634                 (void)memcpy(address, entry->address, 6);
3635                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3636                 btstack_memory_whitelist_entry_free(entry);
3637                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3638                 return true;
3639             }
3640         }
3641     }
3642 
3643     // start connecting
3644     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3645          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3646         bd_addr_t null_addr;
3647         memset(null_addr, 0, 6);
3648         hci_send_cmd(&hci_le_create_connection,
3649                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3650                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3651                      1,         // use whitelist
3652                      0,         // peer address type
3653                      null_addr, // peer bd addr
3654                      hci_stack->le_own_addr_type, // our addr type:
3655                      hci_stack->le_connection_interval_min,    // conn interval min
3656                      hci_stack->le_connection_interval_max,    // conn interval max
3657                      hci_stack->le_connection_latency,         // conn latency
3658                      hci_stack->le_supervision_timeout,        // conn latency
3659                      hci_stack->le_minimum_ce_length,          // min ce length
3660                      hci_stack->le_maximum_ce_length           // max ce length
3661         );
3662         return true;
3663     }
3664 #endif
3665     return false;
3666 }
3667 #endif
3668 
3669 static bool hci_run_general_pending_commmands(void){
3670     btstack_linked_item_t * it;
3671     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3672         hci_connection_t * connection = (hci_connection_t *) it;
3673 
3674         switch(connection->state){
3675             case SEND_CREATE_CONNECTION:
3676                 switch(connection->address_type){
3677 #ifdef ENABLE_CLASSIC
3678                     case BD_ADDR_TYPE_ACL:
3679                         log_info("sending hci_create_connection");
3680                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3681                         break;
3682 #endif
3683                     default:
3684 #ifdef ENABLE_BLE
3685 #ifdef ENABLE_LE_CENTRAL
3686                         // track outgoing connection
3687                         hci_stack->outgoing_addr_type = connection->address_type;
3688                         (void)memcpy(hci_stack->outgoing_addr,
3689                                      connection->address, 6);
3690                         log_info("sending hci_le_create_connection");
3691                         hci_send_cmd(&hci_le_create_connection,
3692                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3693                                      hci_stack->le_connection_scan_window,      // conn scan windows
3694                                      0,         // don't use whitelist
3695                                      connection->address_type, // peer address type
3696                                      connection->address,      // peer bd addr
3697                                      hci_stack->le_own_addr_type, // our addr type:
3698                                      hci_stack->le_connection_interval_min,    // conn interval min
3699                                      hci_stack->le_connection_interval_max,    // conn interval max
3700                                      hci_stack->le_connection_latency,         // conn latency
3701                                      hci_stack->le_supervision_timeout,        // conn latency
3702                                      hci_stack->le_minimum_ce_length,          // min ce length
3703                                      hci_stack->le_maximum_ce_length          // max ce length
3704                         );
3705                         connection->state = SENT_CREATE_CONNECTION;
3706 #endif
3707 #endif
3708                         break;
3709                 }
3710                 return true;
3711 
3712 #ifdef ENABLE_CLASSIC
3713             case RECEIVED_CONNECTION_REQUEST:
3714                 connection->role  = HCI_ROLE_SLAVE;
3715                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3716                     log_info("sending hci_accept_connection_request");
3717                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3718                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3719                 }
3720                 return true;
3721 #endif
3722 
3723 #ifdef ENABLE_BLE
3724 #ifdef ENABLE_LE_CENTRAL
3725             case SEND_CANCEL_CONNECTION:
3726                 connection->state = SENT_CANCEL_CONNECTION;
3727                 hci_send_cmd(&hci_le_create_connection_cancel);
3728                 return true;
3729 #endif
3730 #endif
3731             case SEND_DISCONNECT:
3732                 connection->state = SENT_DISCONNECT;
3733                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3734                 return true;
3735 
3736             default:
3737                 break;
3738         }
3739 
3740         // no further commands if connection is about to get shut down
3741         if (connection->state == SENT_DISCONNECT) continue;
3742 
3743         if (connection->authentication_flags & READ_RSSI){
3744             connectionClearAuthenticationFlags(connection, READ_RSSI);
3745             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3746             return true;
3747         }
3748 
3749 #ifdef ENABLE_CLASSIC
3750 
3751         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3752             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3753             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3754             return true;
3755         }
3756 
3757         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3758             log_info("responding to link key request");
3759             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3760             link_key_t link_key;
3761             link_key_type_t link_key_type;
3762             if ( hci_stack->link_key_db
3763                  && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3764                  && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level)){
3765                 connection->link_key_type = link_key_type;
3766                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3767             } else {
3768                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3769             }
3770             return true;
3771         }
3772 
3773         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3774             log_info("denying to pin request");
3775             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3776             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3777             return true;
3778         }
3779 
3780         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3781             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3782             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3783             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3784                 // tweak authentication requirements
3785                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3786                 if (connection->bonding_flags & BONDING_DEDICATED){
3787                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3788                 }
3789                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3790                     authreq |= 1;
3791                 }
3792                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3793             } else {
3794                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3795             }
3796             return true;
3797         }
3798 
3799         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3800             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3801             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3802             return true;
3803         }
3804 
3805         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3806             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3807             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3808             return true;
3809         }
3810 
3811         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3812             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3813             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3814             return true;
3815         }
3816 
3817         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3818             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3819             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3820             return true;
3821         }
3822 
3823         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3824             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3825             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3826             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3827             return true;
3828         }
3829 
3830         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3831             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3832             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3833             return true;
3834         }
3835 
3836         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3837             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3838             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3839             return true;
3840         }
3841         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3842             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3843             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3844             return true;
3845         }
3846 #endif
3847 
3848         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3849             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3850             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3851             return true;
3852         }
3853 
3854 #ifdef ENABLE_CLASSIC
3855         uint16_t sniff_min_interval;
3856         switch (connection->sniff_min_interval){
3857             case 0:
3858                 break;
3859             case 0xffff:
3860                 connection->sniff_min_interval = 0;
3861                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3862                 return true;
3863             default:
3864                 sniff_min_interval = connection->sniff_min_interval;
3865                 connection->sniff_min_interval = 0;
3866                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3867                 return true;
3868         }
3869 #endif
3870 
3871 #ifdef ENABLE_BLE
3872         switch (connection->le_con_parameter_update_state){
3873             // response to L2CAP CON PARAMETER UPDATE REQUEST
3874             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3875                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3876                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3877                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3878                              0x0000, 0xffff);
3879                 return true;
3880             case CON_PARAMETER_UPDATE_REPLY:
3881                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3882                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3883                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3884                              0x0000, 0xffff);
3885                 return true;
3886             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3887                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3888                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3889                 return true;
3890             default:
3891                 break;
3892         }
3893         if (connection->le_phy_update_all_phys != 0xff){
3894             uint8_t all_phys = connection->le_phy_update_all_phys;
3895             connection->le_phy_update_all_phys = 0xff;
3896             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);
3897             return true;
3898         }
3899 #endif
3900     }
3901     return false;
3902 }
3903 
3904 static void hci_run(void){
3905 
3906     bool done;
3907 
3908     // send continuation fragments first, as they block the prepared packet buffer
3909     done = hci_run_acl_fragments();
3910     if (done) return;
3911 
3912 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3913     // send host num completed packets next as they don't require num_cmd_packets > 0
3914     if (!hci_can_send_comand_packet_transport()) return;
3915     if (hci_stack->host_completed_packets){
3916         hci_host_num_completed_packets();
3917         return;
3918     }
3919 #endif
3920 
3921     if (!hci_can_send_command_packet_now()) return;
3922 
3923     // global/non-connection oriented commands
3924 
3925 
3926 #ifdef ENABLE_CLASSIC
3927     // general gap classic
3928     done = hci_run_general_gap_classic();
3929     if (done) return;
3930 #endif
3931 
3932 #ifdef ENABLE_BLE
3933     // general gap le
3934     done = hci_run_general_gap_le();
3935     if (done) return;
3936 #endif
3937 
3938     // send pending HCI commands
3939     done = hci_run_general_pending_commmands();
3940     if (done) return;
3941 
3942     // stack state sub statemachines
3943     hci_connection_t * connection;
3944     switch (hci_stack->state){
3945         case HCI_STATE_INITIALIZING:
3946             hci_initializing_run();
3947             break;
3948 
3949         case HCI_STATE_HALTING:
3950 
3951             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3952             switch (hci_stack->substate){
3953                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3954                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3955 
3956 #ifdef ENABLE_BLE
3957 #ifdef ENABLE_LE_CENTRAL
3958                     // free whitelist entries
3959                     {
3960                         btstack_linked_list_iterator_t lit;
3961                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3962                         while (btstack_linked_list_iterator_has_next(&lit)){
3963                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3964                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3965                             btstack_memory_whitelist_entry_free(entry);
3966                         }
3967                     }
3968 #endif
3969 #endif
3970                     // close all open connections
3971                     connection =  (hci_connection_t *) hci_stack->connections;
3972                     if (connection){
3973                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3974                         if (!hci_can_send_command_packet_now()) return;
3975 
3976                         // check state
3977                         if (connection->state == SENT_DISCONNECT) return;
3978                         connection->state = SENT_DISCONNECT;
3979 
3980                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3981 
3982                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3983                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3984 
3985                         // ... which would be ignored anyway as we shutdown (free) the connection now
3986                         hci_shutdown_connection(connection);
3987 
3988                         // finally, send the disconnect command
3989                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3990                         return;
3991                     }
3992 
3993                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
3994                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
3995                         log_info("HCI_STATE_HALTING: wait 50 ms");
3996                         hci_stack->substate = HCI_HALTING_W4_TIMER;
3997                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
3998                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3999                         btstack_run_loop_add_timer(&hci_stack->timeout);
4000                         break;
4001                     }
4002 
4003                     /* fall through */
4004 
4005                 case HCI_HALTING_CLOSE:
4006                     log_info("HCI_STATE_HALTING, calling off");
4007 
4008                     // switch mode
4009                     hci_power_control_off();
4010 
4011                     log_info("HCI_STATE_HALTING, emitting state");
4012                     hci_emit_state();
4013                     log_info("HCI_STATE_HALTING, done");
4014                     break;
4015 
4016                 case HCI_HALTING_W4_TIMER:
4017                     // keep waiting
4018 
4019                     break;
4020                 default:
4021                     break;
4022             }
4023 
4024             break;
4025 
4026         case HCI_STATE_FALLING_ASLEEP:
4027             switch(hci_stack->substate) {
4028                 case HCI_FALLING_ASLEEP_DISCONNECT:
4029                     log_info("HCI_STATE_FALLING_ASLEEP");
4030                     // close all open connections
4031                     connection =  (hci_connection_t *) hci_stack->connections;
4032 
4033 #ifdef HAVE_PLATFORM_IPHONE_OS
4034                     // don't close connections, if H4 supports power management
4035                     if (btstack_control_iphone_power_management_enabled()){
4036                         connection = NULL;
4037                     }
4038 #endif
4039                     if (connection){
4040 
4041                         // send disconnect
4042                         if (!hci_can_send_command_packet_now()) return;
4043 
4044                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4045                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
4046 
4047                         // send disconnected event right away - causes higher layer connections to get closed, too.
4048                         hci_shutdown_connection(connection);
4049                         return;
4050                     }
4051 
4052                     if (hci_classic_supported()){
4053                         // disable page and inquiry scan
4054                         if (!hci_can_send_command_packet_now()) return;
4055 
4056                         log_info("HCI_STATE_HALTING, disabling inq scans");
4057                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4058 
4059                         // continue in next sub state
4060                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4061                         break;
4062                     }
4063 
4064                     /* fall through */
4065 
4066                 case HCI_FALLING_ASLEEP_COMPLETE:
4067                     log_info("HCI_STATE_HALTING, calling sleep");
4068 #ifdef HAVE_PLATFORM_IPHONE_OS
4069                     // don't actually go to sleep, if H4 supports power management
4070                     if (btstack_control_iphone_power_management_enabled()){
4071                         // SLEEP MODE reached
4072                         hci_stack->state = HCI_STATE_SLEEPING;
4073                         hci_emit_state();
4074                         break;
4075                     }
4076 #endif
4077                     // switch mode
4078                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4079                     hci_emit_state();
4080                     break;
4081 
4082                 default:
4083                     break;
4084             }
4085             break;
4086 
4087         default:
4088             break;
4089     }
4090 }
4091 
4092 int hci_send_cmd_packet(uint8_t *packet, int size){
4093     // house-keeping
4094 
4095     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4096         hci_stack->loopback_mode = packet[3];
4097     }
4098 
4099 #ifdef ENABLE_CLASSIC
4100     bd_addr_t addr;
4101     hci_connection_t * conn;
4102 
4103     // create_connection?
4104     if (IS_COMMAND(packet, hci_create_connection)){
4105         reverse_bd_addr(&packet[3], addr);
4106         log_info("Create_connection to %s", bd_addr_to_str(addr));
4107 
4108         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4109         if (!conn){
4110             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4111             if (!conn){
4112                 // notify client that alloc failed
4113                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4114                 return -1; // packet not sent to controller
4115             }
4116             conn->state = SEND_CREATE_CONNECTION;
4117         }
4118         log_info("conn state %u", conn->state);
4119         switch (conn->state){
4120             // if connection active exists
4121             case OPEN:
4122                 // and OPEN, emit connection complete command
4123                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4124                 return -1; // packet not sent to controller
4125             case RECEIVED_DISCONNECTION_COMPLETE:
4126                 // create connection triggered in disconnect complete event, let's do it now
4127                 break;
4128             case SEND_CREATE_CONNECTION:
4129                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4130                 break;
4131             default:
4132                 // otherwise, just ignore as it is already in the open process
4133                 return -1; // packet not sent to controller
4134         }
4135         conn->state = SENT_CREATE_CONNECTION;
4136 
4137         // track outgoing connection
4138         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4139         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4140     }
4141 
4142     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4143         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4144     }
4145     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4146         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4147     }
4148 
4149     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4150         if (hci_stack->link_key_db){
4151             reverse_bd_addr(&packet[3], addr);
4152             hci_stack->link_key_db->delete_link_key(addr);
4153         }
4154     }
4155 
4156     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4157     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4158         reverse_bd_addr(&packet[3], addr);
4159         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4160         if (conn){
4161             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4162         }
4163     }
4164 
4165     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4166     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4167     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4168     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4169         reverse_bd_addr(&packet[3], addr);
4170         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4171         if (conn){
4172             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4173         }
4174     }
4175 
4176 #ifdef ENABLE_SCO_OVER_HCI
4177     // setup_synchronous_connection? Voice setting at offset 22
4178     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4179         // TODO: compare to current setting if sco connection already active
4180         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4181     }
4182     // accept_synchronus_connection? Voice setting at offset 18
4183     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4184         // TODO: compare to current setting if sco connection already active
4185         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4186     }
4187 #endif
4188 #endif
4189 
4190 #ifdef ENABLE_BLE
4191     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4192         hci_stack->le_random_address_set = 1;
4193         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4194     }
4195 #ifdef ENABLE_LE_PERIPHERAL
4196     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4197         hci_stack->le_advertisements_active = packet[3];
4198     }
4199 #endif
4200 #ifdef ENABLE_LE_CENTRAL
4201     else if (IS_COMMAND(packet, hci_le_create_connection)){
4202         // white list used?
4203         uint8_t initiator_filter_policy = packet[7];
4204         switch (initiator_filter_policy){
4205             case 0:
4206                 // whitelist not used
4207                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4208                 break;
4209             case 1:
4210                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4211                 break;
4212             default:
4213                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4214                 break;
4215         }
4216     }
4217     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4218         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4219     }
4220 #endif
4221 #endif
4222 
4223     hci_stack->num_cmd_packets--;
4224 
4225     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4226     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4227 }
4228 
4229 // disconnect because of security block
4230 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4231     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4232     if (!connection) return;
4233     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4234 }
4235 
4236 
4237 // Configure Secure Simple Pairing
4238 
4239 #ifdef ENABLE_CLASSIC
4240 
4241 // enable will enable SSP during init
4242 void gap_ssp_set_enable(int enable){
4243     hci_stack->ssp_enable = enable;
4244 }
4245 
4246 static int hci_local_ssp_activated(void){
4247     return gap_ssp_supported() && hci_stack->ssp_enable;
4248 }
4249 
4250 // if set, BTstack will respond to io capability request using authentication requirement
4251 void gap_ssp_set_io_capability(int io_capability){
4252     hci_stack->ssp_io_capability = io_capability;
4253 }
4254 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4255     hci_stack->ssp_authentication_requirement = authentication_requirement;
4256 }
4257 
4258 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4259 void gap_ssp_set_auto_accept(int auto_accept){
4260     hci_stack->ssp_auto_accept = auto_accept;
4261 }
4262 
4263 void gap_secure_connections_enable(bool enable){
4264     hci_stack->secure_connections_enable = enable;
4265 }
4266 
4267 #endif
4268 
4269 // va_list part of hci_send_cmd
4270 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4271     if (!hci_can_send_command_packet_now()){
4272         log_error("hci_send_cmd called but cannot send packet now");
4273         return 0;
4274     }
4275 
4276     // for HCI INITIALIZATION
4277     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4278     hci_stack->last_cmd_opcode = cmd->opcode;
4279 
4280     hci_reserve_packet_buffer();
4281     uint8_t * packet = hci_stack->hci_packet_buffer;
4282     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4283     int err = hci_send_cmd_packet(packet, size);
4284 
4285     // release packet buffer on error or for synchronous transport implementations
4286     if ((err < 0) || hci_transport_synchronous()){
4287         hci_release_packet_buffer();
4288         hci_emit_transport_packet_sent();
4289     }
4290 
4291     return err;
4292 }
4293 
4294 /**
4295  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4296  */
4297 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4298     va_list argptr;
4299     va_start(argptr, cmd);
4300     int res = hci_send_cmd_va_arg(cmd, argptr);
4301     va_end(argptr);
4302     return res;
4303 }
4304 
4305 // Create various non-HCI events.
4306 // TODO: generalize, use table similar to hci_create_command
4307 
4308 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4309     // dump packet
4310     if (dump) {
4311         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4312     }
4313 
4314     // dispatch to all event handlers
4315     btstack_linked_list_iterator_t it;
4316     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4317     while (btstack_linked_list_iterator_has_next(&it)){
4318         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4319         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4320     }
4321 }
4322 
4323 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4324     if (!hci_stack->acl_packet_handler) return;
4325     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4326 }
4327 
4328 #ifdef ENABLE_CLASSIC
4329 static void hci_notify_if_sco_can_send_now(void){
4330     // notify SCO sender if waiting
4331     if (!hci_stack->sco_waiting_for_can_send_now) return;
4332     if (hci_can_send_sco_packet_now()){
4333         hci_stack->sco_waiting_for_can_send_now = 0;
4334         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4335         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4336         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4337     }
4338 }
4339 
4340 // parsing end emitting has been merged to reduce code size
4341 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4342     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4343 
4344     uint8_t * eir_data;
4345     ad_context_t context;
4346     const uint8_t * name;
4347     uint8_t         name_len;
4348 
4349     if (size < 3) return;
4350 
4351     int event_type = hci_event_packet_get_type(packet);
4352     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4353     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4354 
4355     switch (event_type){
4356         case HCI_EVENT_INQUIRY_RESULT:
4357         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4358             if (size != (3 + (num_responses * 14))) return;
4359             break;
4360         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4361             if (size != 257) return;
4362             if (num_responses != 1) return;
4363             break;
4364         default:
4365             return;
4366     }
4367 
4368     // event[1] is set at the end
4369     int i;
4370     for (i=0; i<num_responses;i++){
4371         memset(event, 0, sizeof(event));
4372         event[0] = GAP_EVENT_INQUIRY_RESULT;
4373         uint8_t event_size = 18;    // if name is not set by EIR
4374 
4375         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4376         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4377         (void)memcpy(&event[9],
4378                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4379                      3); // class of device
4380         (void)memcpy(&event[12],
4381                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4382                      2); // clock offset
4383 
4384         switch (event_type){
4385             case HCI_EVENT_INQUIRY_RESULT:
4386                 // 14,15,16,17 = 0, size 18
4387                 break;
4388             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4389                 event[14] = 1;
4390                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4391                 // 16,17 = 0, size 18
4392                 break;
4393             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4394                 event[14] = 1;
4395                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4396                 // EIR packets only contain a single inquiry response
4397                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4398                 name = NULL;
4399                 // Iterate over EIR data
4400                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4401                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4402                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4403                     const uint8_t * data = ad_iterator_get_data(&context);
4404                     // Prefer Complete Local Name over Shortend Local Name
4405                     switch (data_type){
4406                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4407                             if (name) continue;
4408                             /* fall through */
4409                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4410                             name = data;
4411                             name_len = data_size;
4412                             break;
4413                         default:
4414                             break;
4415                     }
4416                 }
4417                 if (name){
4418                     event[16] = 1;
4419                     // truncate name if needed
4420                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4421                     event[17] = len;
4422                     (void)memcpy(&event[18], name, len);
4423                     event_size += len;
4424                 }
4425                 break;
4426         }
4427         event[1] = event_size - 2;
4428         hci_emit_event(event, event_size, 1);
4429     }
4430 }
4431 #endif
4432 
4433 void hci_emit_state(void){
4434     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4435     uint8_t event[3];
4436     event[0] = BTSTACK_EVENT_STATE;
4437     event[1] = sizeof(event) - 2;
4438     event[2] = hci_stack->state;
4439     hci_emit_event(event, sizeof(event), 1);
4440 }
4441 
4442 #ifdef ENABLE_CLASSIC
4443 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4444     uint8_t event[13];
4445     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4446     event[1] = sizeof(event) - 2;
4447     event[2] = status;
4448     little_endian_store_16(event, 3, con_handle);
4449     reverse_bd_addr(address, &event[5]);
4450     event[11] = 1; // ACL connection
4451     event[12] = 0; // encryption disabled
4452     hci_emit_event(event, sizeof(event), 1);
4453 }
4454 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4455     if (disable_l2cap_timeouts) return;
4456     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4457     uint8_t event[4];
4458     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4459     event[1] = sizeof(event) - 2;
4460     little_endian_store_16(event, 2, conn->con_handle);
4461     hci_emit_event(event, sizeof(event), 1);
4462 }
4463 #endif
4464 
4465 #ifdef ENABLE_BLE
4466 #ifdef ENABLE_LE_CENTRAL
4467 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4468     uint8_t event[21];
4469     event[0] = HCI_EVENT_LE_META;
4470     event[1] = sizeof(event) - 2;
4471     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4472     event[3] = status;
4473     little_endian_store_16(event, 4, con_handle);
4474     event[6] = 0; // TODO: role
4475     event[7] = address_type;
4476     reverse_bd_addr(address, &event[8]);
4477     little_endian_store_16(event, 14, 0); // interval
4478     little_endian_store_16(event, 16, 0); // latency
4479     little_endian_store_16(event, 18, 0); // supervision timeout
4480     event[20] = 0; // master clock accuracy
4481     hci_emit_event(event, sizeof(event), 1);
4482 }
4483 #endif
4484 #endif
4485 
4486 static void hci_emit_transport_packet_sent(void){
4487     // notify upper stack that it might be possible to send again
4488     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4489     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4490 }
4491 
4492 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4493     uint8_t event[6];
4494     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4495     event[1] = sizeof(event) - 2;
4496     event[2] = 0; // status = OK
4497     little_endian_store_16(event, 3, con_handle);
4498     event[5] = reason;
4499     hci_emit_event(event, sizeof(event), 1);
4500 }
4501 
4502 static void hci_emit_nr_connections_changed(void){
4503     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4504     uint8_t event[3];
4505     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4506     event[1] = sizeof(event) - 2;
4507     event[2] = nr_hci_connections();
4508     hci_emit_event(event, sizeof(event), 1);
4509 }
4510 
4511 static void hci_emit_hci_open_failed(void){
4512     log_info("BTSTACK_EVENT_POWERON_FAILED");
4513     uint8_t event[2];
4514     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4515     event[1] = sizeof(event) - 2;
4516     hci_emit_event(event, sizeof(event), 1);
4517 }
4518 
4519 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4520     log_info("hci_emit_dedicated_bonding_result %u ", status);
4521     uint8_t event[9];
4522     int pos = 0;
4523     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4524     event[pos++] = sizeof(event) - 2;
4525     event[pos++] = status;
4526     reverse_bd_addr(address, &event[pos]);
4527     hci_emit_event(event, sizeof(event), 1);
4528 }
4529 
4530 
4531 #ifdef ENABLE_CLASSIC
4532 
4533 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4534     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4535     uint8_t event[5];
4536     int pos = 0;
4537     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4538     event[pos++] = sizeof(event) - 2;
4539     little_endian_store_16(event, 2, con_handle);
4540     pos += 2;
4541     event[pos++] = level;
4542     hci_emit_event(event, sizeof(event), 1);
4543 }
4544 
4545 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4546     if (!connection) return LEVEL_0;
4547     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4548     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4549     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4550     // LEVEL 4 always requires 128 bit encrytion key size
4551     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4552         security_level = LEVEL_3;
4553     }
4554     return security_level;
4555 }
4556 
4557 static void hci_emit_discoverable_enabled(uint8_t enabled){
4558     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4559     uint8_t event[3];
4560     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4561     event[1] = sizeof(event) - 2;
4562     event[2] = enabled;
4563     hci_emit_event(event, sizeof(event), 1);
4564 }
4565 
4566 // query if remote side supports eSCO
4567 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4568     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4569     if (!connection) return 0;
4570     return (connection->remote_supported_features[0] & 1) != 0;
4571 }
4572 
4573 static bool hci_ssp_supported(hci_connection_t * connection){
4574     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4575     return (connection->bonding_flags & mask) == mask;
4576 }
4577 
4578 // query if remote side supports SSP
4579 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4580     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4581     if (!connection) return 0;
4582     return hci_ssp_supported(connection) ? 1 : 0;
4583 }
4584 
4585 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4586     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4587 }
4588 
4589 // GAP API
4590 /**
4591  * @bbrief enable/disable bonding. default is enabled
4592  * @praram enabled
4593  */
4594 void gap_set_bondable_mode(int enable){
4595     hci_stack->bondable = enable ? 1 : 0;
4596 }
4597 /**
4598  * @brief Get bondable mode.
4599  * @return 1 if bondable
4600  */
4601 int gap_get_bondable_mode(void){
4602     return hci_stack->bondable;
4603 }
4604 
4605 /**
4606  * @brief map link keys to security levels
4607  */
4608 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4609     switch (link_key_type){
4610         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4611             return LEVEL_4;
4612         case COMBINATION_KEY:
4613         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4614             return LEVEL_3;
4615         default:
4616             return LEVEL_2;
4617     }
4618 }
4619 
4620 /**
4621  * @brief map link keys to secure connection yes/no
4622  */
4623 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4624     switch (link_key_type){
4625         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4626         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4627             return 1;
4628         default:
4629             return 0;
4630     }
4631 }
4632 
4633 /**
4634  * @brief map link keys to authenticated
4635  */
4636 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4637     switch (link_key_type){
4638         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4639         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4640             return 1;
4641         default:
4642             return 0;
4643     }
4644 }
4645 
4646 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4647     log_info("gap_mitm_protection_required_for_security_level %u", level);
4648     return level > LEVEL_2;
4649 }
4650 
4651 /**
4652  * @brief get current security level
4653  */
4654 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4655     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4656     if (!connection) return LEVEL_0;
4657     return gap_security_level_for_connection(connection);
4658 }
4659 
4660 /**
4661  * @brief request connection to device to
4662  * @result GAP_AUTHENTICATION_RESULT
4663  */
4664 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4665     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4666     if (!connection){
4667         hci_emit_security_level(con_handle, LEVEL_0);
4668         return;
4669     }
4670     gap_security_level_t current_level = gap_security_level(con_handle);
4671     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4672         requested_level, connection->requested_security_level, current_level);
4673 
4674     // assumption: earlier requested security higher than current level => security request is active
4675     if (current_level < connection->requested_security_level){
4676         if (connection->requested_security_level < requested_level){
4677             // increase requested level as new level is higher
4678 
4679             // TODO: handle re-authentication when done
4680 
4681             connection->requested_security_level = requested_level;
4682         }
4683         return;
4684     }
4685 
4686     // no request active, notify if security sufficient
4687     if (requested_level <= current_level){
4688         hci_emit_security_level(con_handle, current_level);
4689         return;
4690     }
4691 
4692     // start pairing to increase security level
4693     connection->requested_security_level = requested_level;
4694 
4695 #if 0
4696     // sending encryption request without a link key results in an error.
4697     // TODO: figure out how to use it properly
4698 
4699     // would enabling ecnryption suffice (>= LEVEL_2)?
4700     if (hci_stack->link_key_db){
4701         link_key_type_t link_key_type;
4702         link_key_t      link_key;
4703         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4704             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4705                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4706                 return;
4707             }
4708         }
4709     }
4710 #endif
4711 
4712     // start to authenticate connection
4713     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4714     hci_run();
4715 }
4716 
4717 /**
4718  * @brief start dedicated bonding with device. disconnect after bonding
4719  * @param device
4720  * @param request MITM protection
4721  * @result GAP_DEDICATED_BONDING_COMPLETE
4722  */
4723 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4724 
4725     // create connection state machine
4726     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4727 
4728     if (!connection){
4729         return BTSTACK_MEMORY_ALLOC_FAILED;
4730     }
4731 
4732     // delete linkn key
4733     gap_drop_link_key_for_bd_addr(device);
4734 
4735     // configure LEVEL_2/3, dedicated bonding
4736     connection->state = SEND_CREATE_CONNECTION;
4737     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4738     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4739     connection->bonding_flags = BONDING_DEDICATED;
4740 
4741     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4742 
4743     // handle: connnection failure (connection complete != ok)
4744     // handle: authentication failure
4745     // handle: disconnect on done
4746 
4747     hci_run();
4748 
4749     return 0;
4750 }
4751 #endif
4752 
4753 void gap_set_local_name(const char * local_name){
4754     hci_stack->local_name = local_name;
4755 }
4756 
4757 
4758 #ifdef ENABLE_BLE
4759 
4760 #ifdef ENABLE_LE_CENTRAL
4761 void gap_start_scan(void){
4762     hci_stack->le_scanning_enabled = 1;
4763     hci_run();
4764 }
4765 
4766 void gap_stop_scan(void){
4767     hci_stack->le_scanning_enabled = 0;
4768     hci_run();
4769 }
4770 
4771 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4772     hci_stack->le_scan_type     = scan_type;
4773     hci_stack->le_scan_interval = scan_interval;
4774     hci_stack->le_scan_window   = scan_window;
4775     hci_run();
4776 }
4777 
4778 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4779     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4780     if (!conn){
4781         log_info("gap_connect: no connection exists yet, creating context");
4782         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4783         if (!conn){
4784             // notify client that alloc failed
4785             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4786             log_info("gap_connect: failed to alloc hci_connection_t");
4787             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4788         }
4789         conn->state = SEND_CREATE_CONNECTION;
4790         log_info("gap_connect: send create connection next");
4791         hci_run();
4792         return ERROR_CODE_SUCCESS;
4793     }
4794 
4795     if (!hci_is_le_connection(conn) ||
4796         (conn->state == SEND_CREATE_CONNECTION) ||
4797         (conn->state == SENT_CREATE_CONNECTION)) {
4798         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4799         log_error("gap_connect: classic connection or connect is already being created");
4800         return GATT_CLIENT_IN_WRONG_STATE;
4801     }
4802 
4803     // check if connection was just disconnected
4804     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4805         log_info("gap_connect: send create connection (again)");
4806         conn->state = SEND_CREATE_CONNECTION;
4807         hci_run();
4808         return ERROR_CODE_SUCCESS;
4809     }
4810 
4811     log_info("gap_connect: context exists with state %u", conn->state);
4812     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4813     hci_run();
4814     return ERROR_CODE_SUCCESS;
4815 }
4816 
4817 // @assumption: only a single outgoing LE Connection exists
4818 static hci_connection_t * gap_get_outgoing_connection(void){
4819     btstack_linked_item_t *it;
4820     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4821         hci_connection_t * conn = (hci_connection_t *) it;
4822         if (!hci_is_le_connection(conn)) continue;
4823         switch (conn->state){
4824             case SEND_CREATE_CONNECTION:
4825             case SENT_CREATE_CONNECTION:
4826             case SENT_CANCEL_CONNECTION:
4827                 return conn;
4828             default:
4829                 break;
4830         };
4831     }
4832     return NULL;
4833 }
4834 
4835 uint8_t gap_connect_cancel(void){
4836     hci_connection_t * conn = gap_get_outgoing_connection();
4837     if (!conn) return 0;
4838     switch (conn->state){
4839         case SEND_CREATE_CONNECTION:
4840             // skip sending create connection and emit event instead
4841             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4842             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4843             btstack_memory_hci_connection_free( conn );
4844             break;
4845         case SENT_CREATE_CONNECTION:
4846             // request to send cancel connection
4847             conn->state = SEND_CANCEL_CONNECTION;
4848             hci_run();
4849             break;
4850         default:
4851             break;
4852     }
4853     return 0;
4854 }
4855 #endif
4856 
4857 #ifdef ENABLE_LE_CENTRAL
4858 /**
4859  * @brief Set connection parameters for outgoing connections
4860  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4861  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4862  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4863  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4864  * @param conn_latency, default: 4
4865  * @param supervision_timeout (unit: 10ms), default: 720 ms
4866  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4867  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4868  */
4869 
4870 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4871     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4872     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4873     hci_stack->le_connection_scan_interval = conn_scan_interval;
4874     hci_stack->le_connection_scan_window = conn_scan_window;
4875     hci_stack->le_connection_interval_min = conn_interval_min;
4876     hci_stack->le_connection_interval_max = conn_interval_max;
4877     hci_stack->le_connection_latency = conn_latency;
4878     hci_stack->le_supervision_timeout = supervision_timeout;
4879     hci_stack->le_minimum_ce_length = min_ce_length;
4880     hci_stack->le_maximum_ce_length = max_ce_length;
4881 }
4882 #endif
4883 
4884 /**
4885  * @brief Updates the connection parameters for a given LE connection
4886  * @param handle
4887  * @param conn_interval_min (unit: 1.25ms)
4888  * @param conn_interval_max (unit: 1.25ms)
4889  * @param conn_latency
4890  * @param supervision_timeout (unit: 10ms)
4891  * @returns 0 if ok
4892  */
4893 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4894     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4895     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4896     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4897     connection->le_conn_interval_min = conn_interval_min;
4898     connection->le_conn_interval_max = conn_interval_max;
4899     connection->le_conn_latency = conn_latency;
4900     connection->le_supervision_timeout = supervision_timeout;
4901     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4902     hci_run();
4903     return 0;
4904 }
4905 
4906 /**
4907  * @brief Request an update of the connection parameter for a given LE connection
4908  * @param handle
4909  * @param conn_interval_min (unit: 1.25ms)
4910  * @param conn_interval_max (unit: 1.25ms)
4911  * @param conn_latency
4912  * @param supervision_timeout (unit: 10ms)
4913  * @returns 0 if ok
4914  */
4915 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4916     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4917     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4918     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4919     connection->le_conn_interval_min = conn_interval_min;
4920     connection->le_conn_interval_max = conn_interval_max;
4921     connection->le_conn_latency = conn_latency;
4922     connection->le_supervision_timeout = supervision_timeout;
4923     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4924     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4925     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4926     return 0;
4927 }
4928 
4929 #ifdef ENABLE_LE_PERIPHERAL
4930 
4931 static void gap_advertisments_changed(void){
4932     // disable advertisements before updating adv, scan data, or adv params
4933     if (hci_stack->le_advertisements_active){
4934         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4935     }
4936     hci_run();
4937 }
4938 
4939 /**
4940  * @brief Set Advertisement Data
4941  * @param advertising_data_length
4942  * @param advertising_data (max 31 octets)
4943  * @note data is not copied, pointer has to stay valid
4944  */
4945 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4946     hci_stack->le_advertisements_data_len = advertising_data_length;
4947     hci_stack->le_advertisements_data = advertising_data;
4948     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4949     gap_advertisments_changed();
4950 }
4951 
4952 /**
4953  * @brief Set Scan Response Data
4954  * @param advertising_data_length
4955  * @param advertising_data (max 31 octets)
4956  * @note data is not copied, pointer has to stay valid
4957  */
4958 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4959     hci_stack->le_scan_response_data_len = scan_response_data_length;
4960     hci_stack->le_scan_response_data = scan_response_data;
4961     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4962     gap_advertisments_changed();
4963 }
4964 
4965 /**
4966  * @brief Set Advertisement Parameters
4967  * @param adv_int_min
4968  * @param adv_int_max
4969  * @param adv_type
4970  * @param direct_address_type
4971  * @param direct_address
4972  * @param channel_map
4973  * @param filter_policy
4974  *
4975  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4976  */
4977  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4978     uint8_t direct_address_typ, bd_addr_t direct_address,
4979     uint8_t channel_map, uint8_t filter_policy) {
4980 
4981     hci_stack->le_advertisements_interval_min = adv_int_min;
4982     hci_stack->le_advertisements_interval_max = adv_int_max;
4983     hci_stack->le_advertisements_type = adv_type;
4984     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4985     hci_stack->le_advertisements_channel_map = channel_map;
4986     hci_stack->le_advertisements_filter_policy = filter_policy;
4987     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
4988                  6);
4989 
4990     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4991     gap_advertisments_changed();
4992  }
4993 
4994 /**
4995  * @brief Enable/Disable Advertisements
4996  * @param enabled
4997  */
4998 void gap_advertisements_enable(int enabled){
4999     hci_stack->le_advertisements_enabled = enabled;
5000     if (enabled && !hci_stack->le_advertisements_active){
5001         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
5002     }
5003     if (!enabled && hci_stack->le_advertisements_active){
5004         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
5005     }
5006     hci_run();
5007 }
5008 
5009 #endif
5010 
5011 void hci_le_set_own_address_type(uint8_t own_address_type){
5012     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5013     if (own_address_type == hci_stack->le_own_addr_type) return;
5014     hci_stack->le_own_addr_type = own_address_type;
5015 
5016 #ifdef ENABLE_LE_PERIPHERAL
5017     // update advertisement parameters, too
5018     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5019     gap_advertisments_changed();
5020 #endif
5021 #ifdef ENABLE_LE_CENTRAL
5022     // note: we don't update scan parameters or modify ongoing connection attempts
5023 #endif
5024 }
5025 
5026 #endif
5027 
5028 uint8_t gap_disconnect(hci_con_handle_t handle){
5029     hci_connection_t * conn = hci_connection_for_handle(handle);
5030     if (!conn){
5031         hci_emit_disconnection_complete(handle, 0);
5032         return 0;
5033     }
5034     // ignore if already disconnected
5035     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5036         return 0;
5037     }
5038     conn->state = SEND_DISCONNECT;
5039     hci_run();
5040     return 0;
5041 }
5042 
5043 int gap_read_rssi(hci_con_handle_t con_handle){
5044     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5045     if (hci_connection == NULL) return 0;
5046     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5047     hci_run();
5048     return 1;
5049 }
5050 
5051 /**
5052  * @brief Get connection type
5053  * @param con_handle
5054  * @result connection_type
5055  */
5056 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5057     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5058     if (!conn) return GAP_CONNECTION_INVALID;
5059     switch (conn->address_type){
5060         case BD_ADDR_TYPE_LE_PUBLIC:
5061         case BD_ADDR_TYPE_LE_RANDOM:
5062             return GAP_CONNECTION_LE;
5063         case BD_ADDR_TYPE_SCO:
5064             return GAP_CONNECTION_SCO;
5065         case BD_ADDR_TYPE_ACL:
5066             return GAP_CONNECTION_ACL;
5067         default:
5068             return GAP_CONNECTION_INVALID;
5069     }
5070 }
5071 
5072 #ifdef ENABLE_BLE
5073 
5074 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){
5075     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5076     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5077 
5078     conn->le_phy_update_all_phys    = all_phys;
5079     conn->le_phy_update_tx_phys     = tx_phys;
5080     conn->le_phy_update_rx_phys     = rx_phys;
5081     conn->le_phy_update_phy_options = phy_options;
5082 
5083     hci_run();
5084 
5085     return 0;
5086 }
5087 
5088 #ifdef ENABLE_LE_CENTRAL
5089 /**
5090  * @brief Auto Connection Establishment - Start Connecting to device
5091  * @param address_typ
5092  * @param address
5093  * @returns 0 if ok
5094  */
5095 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5096     // check capacity
5097     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5098     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5099     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5100     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5101     entry->address_type = address_type;
5102     (void)memcpy(entry->address, address, 6);
5103     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5104     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5105     hci_run();
5106     return 0;
5107 }
5108 
5109 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5110     btstack_linked_list_iterator_t it;
5111     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5112     while (btstack_linked_list_iterator_has_next(&it)){
5113         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5114         if (entry->address_type != address_type) continue;
5115         if (memcmp(entry->address, address, 6) != 0) continue;
5116         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5117             // remove from controller if already present
5118             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5119             continue;
5120         }
5121         // direclty remove entry from whitelist
5122         btstack_linked_list_iterator_remove(&it);
5123         btstack_memory_whitelist_entry_free(entry);
5124     }
5125 }
5126 
5127 /**
5128  * @brief Auto Connection Establishment - Stop Connecting to device
5129  * @param address_typ
5130  * @param address
5131  * @returns 0 if ok
5132  */
5133 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5134     hci_remove_from_whitelist(address_type, address);
5135     hci_run();
5136     return 0;
5137 }
5138 
5139 /**
5140  * @brief Auto Connection Establishment - Stop everything
5141  * @note  Convenience function to stop all active auto connection attempts
5142  */
5143 void gap_auto_connection_stop_all(void){
5144     btstack_linked_list_iterator_t it;
5145     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5146     while (btstack_linked_list_iterator_has_next(&it)){
5147         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5148         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5149             // remove from controller if already present
5150             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5151             continue;
5152         }
5153         // directly remove entry from whitelist
5154         btstack_linked_list_iterator_remove(&it);
5155         btstack_memory_whitelist_entry_free(entry);
5156     }
5157     hci_run();
5158 }
5159 
5160 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5161     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5162     if (!conn) return 0;
5163     return conn->le_connection_interval;
5164 }
5165 #endif
5166 #endif
5167 
5168 #ifdef ENABLE_CLASSIC
5169 /**
5170  * @brief Set Extended Inquiry Response data
5171  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5172  * @note has to be done before stack starts up
5173  */
5174 void gap_set_extended_inquiry_response(const uint8_t * data){
5175     hci_stack->eir_data = data;
5176 }
5177 
5178 /**
5179  * @brief Start GAP Classic Inquiry
5180  * @param duration in 1.28s units
5181  * @return 0 if ok
5182  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5183  */
5184 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5185     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5186     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5187     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5188         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5189     }
5190     hci_stack->inquiry_state = duration_in_1280ms_units;
5191     hci_run();
5192     return 0;
5193 }
5194 
5195 /**
5196  * @brief Stop GAP Classic Inquiry
5197  * @returns 0 if ok
5198  */
5199 int gap_inquiry_stop(void){
5200     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5201         // emit inquiry complete event, before it even started
5202         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5203         hci_emit_event(event, sizeof(event), 1);
5204         return 0;
5205     }
5206     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5207     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5208     hci_run();
5209     return 0;
5210 }
5211 
5212 
5213 /**
5214  * @brief Remote Name Request
5215  * @param addr
5216  * @param page_scan_repetition_mode
5217  * @param clock_offset only used when bit 15 is set
5218  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5219  */
5220 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5221     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5222     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5223     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5224     hci_stack->remote_name_clock_offset = clock_offset;
5225     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5226     hci_run();
5227     return 0;
5228 }
5229 
5230 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5231     hci_stack->gap_pairing_state = state;
5232     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5233     hci_run();
5234     return 0;
5235 }
5236 
5237 /**
5238  * @brief Legacy Pairing Pin Code Response
5239  * @param addr
5240  * @param pin
5241  * @return 0 if ok
5242  */
5243 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5244     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5245     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5246     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5247 }
5248 
5249 /**
5250  * @brief Abort Legacy Pairing
5251  * @param addr
5252  * @param pin
5253  * @return 0 if ok
5254  */
5255 int gap_pin_code_negative(bd_addr_t addr){
5256     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5257     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5258 }
5259 
5260 /**
5261  * @brief SSP Passkey Response
5262  * @param addr
5263  * @param passkey
5264  * @return 0 if ok
5265  */
5266 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5267     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5268     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5269     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5270 }
5271 
5272 /**
5273  * @brief Abort SSP Passkey Entry/Pairing
5274  * @param addr
5275  * @param pin
5276  * @return 0 if ok
5277  */
5278 int gap_ssp_passkey_negative(bd_addr_t addr){
5279     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5280     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5281 }
5282 
5283 /**
5284  * @brief Accept SSP Numeric Comparison
5285  * @param addr
5286  * @param passkey
5287  * @return 0 if ok
5288  */
5289 int gap_ssp_confirmation_response(bd_addr_t addr){
5290     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5291     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5292 }
5293 
5294 /**
5295  * @brief Abort SSP Numeric Comparison/Pairing
5296  * @param addr
5297  * @param pin
5298  * @return 0 if ok
5299  */
5300 int gap_ssp_confirmation_negative(bd_addr_t addr){
5301     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5302     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5303 }
5304 
5305 /**
5306  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5307  * @param inquiry_mode see bluetooth_defines.h
5308  */
5309 void hci_set_inquiry_mode(inquiry_mode_t mode){
5310     hci_stack->inquiry_mode = mode;
5311 }
5312 
5313 /**
5314  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5315  */
5316 void hci_set_sco_voice_setting(uint16_t voice_setting){
5317     hci_stack->sco_voice_setting = voice_setting;
5318 }
5319 
5320 /**
5321  * @brief Get SCO Voice Setting
5322  * @return current voice setting
5323  */
5324 uint16_t hci_get_sco_voice_setting(void){
5325     return hci_stack->sco_voice_setting;
5326 }
5327 
5328 static int hci_have_usb_transport(void){
5329     if (!hci_stack->hci_transport) return 0;
5330     const char * transport_name = hci_stack->hci_transport->name;
5331     if (!transport_name) return 0;
5332     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5333 }
5334 
5335 /** @brief Get SCO packet length for current SCO Voice setting
5336  *  @note  Using SCO packets of the exact length is required for USB transfer
5337  *  @return Length of SCO packets in bytes (not audio frames)
5338  */
5339 int hci_get_sco_packet_length(void){
5340     int sco_packet_length = 0;
5341 
5342 #ifdef ENABLE_SCO_OVER_HCI
5343 
5344     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5345     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5346 
5347     if (hci_have_usb_transport()){
5348         // see Core Spec for H2 USB Transfer.
5349         // 3 byte SCO header + 24 bytes per connection
5350         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5351         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5352     } else {
5353         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5354         sco_packet_length = 3 + 60 * multiplier;
5355         // assert that it still fits inside an SCO buffer
5356         if (sco_packet_length > hci_stack->sco_data_packet_length){
5357             sco_packet_length = 3 + 60;
5358         }
5359     }
5360 #endif
5361     return sco_packet_length;
5362 }
5363 
5364 /**
5365 * @brief Sets the master/slave policy
5366 * @param policy (0: attempt to become master, 1: let connecting device decide)
5367 */
5368 void hci_set_master_slave_policy(uint8_t policy){
5369     hci_stack->master_slave_policy = policy;
5370 }
5371 
5372 #endif
5373 
5374 HCI_STATE hci_get_state(void){
5375     return hci_stack->state;
5376 }
5377 
5378 #ifdef ENABLE_CLASSIC
5379 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5380     hci_stack->gap_classic_accept_callback = accept_callback;
5381 }
5382 #endif
5383 
5384 /**
5385  * @brief Set callback for Bluetooth Hardware Error
5386  */
5387 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5388     hci_stack->hardware_error_callback = fn;
5389 }
5390 
5391 void hci_disconnect_all(void){
5392     btstack_linked_list_iterator_t it;
5393     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5394     while (btstack_linked_list_iterator_has_next(&it)){
5395         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5396         if (con->state == SENT_DISCONNECT) continue;
5397         con->state = SEND_DISCONNECT;
5398     }
5399     hci_run();
5400 }
5401 
5402 uint16_t hci_get_manufacturer(void){
5403     return hci_stack->manufacturer;
5404 }
5405 
5406 #ifdef ENABLE_BLE
5407 
5408 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5409     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5410     if (!hci_con) return NULL;
5411     return &hci_con->sm_connection;
5412 }
5413 
5414 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5415 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5416 
5417 int gap_encryption_key_size(hci_con_handle_t con_handle){
5418     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5419     if (hci_connection == NULL) return 0;
5420     if (hci_is_le_connection(hci_connection)){
5421         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5422         if (sm_conn->sm_connection_encrypted) {
5423             return sm_conn->sm_actual_encryption_key_size;
5424         }
5425     }
5426 #ifdef ENABLE_CLASSIC
5427     else {
5428         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5429             return hci_connection->encryption_key_size;
5430         }
5431     }
5432 #endif
5433     return 0;
5434 }
5435 
5436 int gap_authenticated(hci_con_handle_t con_handle){
5437     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5438     if (hci_connection == NULL) return 0;
5439 
5440     switch (hci_connection->address_type){
5441         case BD_ADDR_TYPE_LE_PUBLIC:
5442         case BD_ADDR_TYPE_LE_RANDOM:
5443             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5444             return hci_connection->sm_connection.sm_connection_authenticated;
5445 #ifdef ENABLE_CLASSIC
5446         case BD_ADDR_TYPE_SCO:
5447         case BD_ADDR_TYPE_ACL:
5448             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5449 #endif
5450         default:
5451             return 0;
5452     }
5453 }
5454 
5455 int gap_secure_connection(hci_con_handle_t con_handle){
5456     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5457     if (hci_connection == NULL) return 0;
5458 
5459     switch (hci_connection->address_type){
5460         case BD_ADDR_TYPE_LE_PUBLIC:
5461         case BD_ADDR_TYPE_LE_RANDOM:
5462             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5463             return hci_connection->sm_connection.sm_connection_sc;
5464 #ifdef ENABLE_CLASSIC
5465         case BD_ADDR_TYPE_SCO:
5466         case BD_ADDR_TYPE_ACL:
5467             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5468 #endif
5469         default:
5470             return 0;
5471     }
5472 }
5473 
5474 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5475     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5476     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5477     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5478     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5479     return sm_conn->sm_connection_authorization_state;
5480 }
5481 #endif
5482 
5483 #ifdef ENABLE_CLASSIC
5484 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){
5485     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5486     if (!conn) return GAP_CONNECTION_INVALID;
5487     conn->sniff_min_interval = sniff_min_interval;
5488     conn->sniff_max_interval = sniff_max_interval;
5489     conn->sniff_attempt = sniff_attempt;
5490     conn->sniff_timeout = sniff_timeout;
5491     hci_run();
5492     return 0;
5493 }
5494 
5495 /**
5496  * @brief Exit Sniff mode
5497  * @param con_handle
5498  @ @return 0 if ok
5499  */
5500 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5501     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5502     if (!conn) return GAP_CONNECTION_INVALID;
5503     conn->sniff_min_interval = 0xffff;
5504     hci_run();
5505     return 0;
5506 }
5507 #endif
5508 
5509 void hci_halting_defer(void){
5510     if (hci_stack->state != HCI_STATE_HALTING) return;
5511     switch (hci_stack->substate){
5512         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5513         case HCI_HALTING_CLOSE:
5514             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5515             break;
5516         default:
5517             break;
5518     }
5519 }
5520 
5521 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5522 void hci_setup_test_connections_fuzz(void){
5523     hci_connection_t * conn;
5524 
5525     // default address: 66:55:44:33:00:01
5526     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5527 
5528     // setup Controller info
5529     hci_stack->num_cmd_packets = 255;
5530     hci_stack->acl_packets_total_num = 255;
5531 
5532     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5533     addr[5] = 0x01;
5534     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5535     conn->con_handle = addr[5];
5536     conn->role  = HCI_ROLE_SLAVE;
5537     conn->state = RECEIVED_CONNECTION_REQUEST;
5538     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5539 
5540     // setup incoming Classic SCO connection with con handle 0x0002
5541     addr[5] = 0x02;
5542     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5543     conn->con_handle = addr[5];
5544     conn->role  = HCI_ROLE_SLAVE;
5545     conn->state = RECEIVED_CONNECTION_REQUEST;
5546     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5547 
5548     // setup ready Classic ACL connection with con handle 0x0003
5549     addr[5] = 0x03;
5550     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5551     conn->con_handle = addr[5];
5552     conn->role  = HCI_ROLE_SLAVE;
5553     conn->state = OPEN;
5554     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5555 
5556     // setup ready Classic SCO connection with con handle 0x0004
5557     addr[5] = 0x04;
5558     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5559     conn->con_handle = addr[5];
5560     conn->role  = HCI_ROLE_SLAVE;
5561     conn->state = OPEN;
5562     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5563 
5564     // setup ready LE ACL connection with con handle 0x005 and public address
5565     addr[5] = 0x05;
5566     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5567     conn->con_handle = addr[5];
5568     conn->role  = HCI_ROLE_SLAVE;
5569     conn->state = OPEN;
5570     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5571 }
5572 
5573 void hci_free_connections_fuzz(void){
5574     btstack_linked_list_iterator_t it;
5575     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5576     while (btstack_linked_list_iterator_has_next(&it)){
5577         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5578         btstack_linked_list_iterator_remove(&it);
5579         btstack_memory_hci_connection_free(con);
5580     }
5581 }
5582 void hci_simulate_working_fuzz(void){
5583     hci_init_done();
5584     hci_stack->num_cmd_packets = 255;
5585 }
5586 #endif
5587