xref: /btstack/src/hci.c (revision 30e72d78ecf7c5a850d87827620ee219f140fb4e)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <stdio.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
136 static bool hci_ssp_supported(hci_connection_t * connection);
137 static void hci_notify_if_sco_can_send_now(void);
138 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
139 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
140 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
141 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
142 static void hci_connection_timestamp(hci_connection_t *connection);
143 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
144 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
145 #endif
146 
147 static int  hci_power_control_on(void);
148 static void hci_power_control_off(void);
149 static void hci_state_reset(void);
150 static void hci_emit_transport_packet_sent(void);
151 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
152 static void hci_emit_nr_connections_changed(void);
153 static void hci_emit_hci_open_failed(void);
154 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
155 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
156 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
157 static void hci_run(void);
158 static int  hci_is_le_connection(hci_connection_t * connection);
159 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
160 
161 #ifdef ENABLE_CLASSIC
162 static int hci_have_usb_transport(void);
163 #endif
164 
165 #ifdef ENABLE_BLE
166 #ifdef ENABLE_LE_CENTRAL
167 // called from test/ble_client/advertising_data_parser.c
168 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
169 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address);
170 static hci_connection_t * gap_get_outgoing_connection(void);
171 #endif
172 #endif
173 
174 // the STACK is here
175 #ifndef HAVE_MALLOC
176 static hci_stack_t   hci_stack_static;
177 #endif
178 static hci_stack_t * hci_stack = NULL;
179 
180 #ifdef ENABLE_CLASSIC
181 // default name
182 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
183 
184 // test helper
185 static uint8_t disable_l2cap_timeouts = 0;
186 #endif
187 
188 /**
189  * create connection for given address
190  *
191  * @return connection OR NULL, if no memory left
192  */
193 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
194     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
195     hci_connection_t * conn = btstack_memory_hci_connection_get();
196     if (!conn) return NULL;
197     bd_addr_copy(conn->address, addr);
198     conn->address_type = addr_type;
199     conn->con_handle = 0xffff;
200     conn->authentication_flags = AUTH_FLAGS_NONE;
201     conn->bonding_flags = 0;
202     conn->requested_security_level = LEVEL_0;
203 #ifdef ENABLE_CLASSIC
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
220     return conn;
221 }
222 
223 
224 /**
225  * get le connection parameter range
226 *
227  * @return le connection parameter range struct
228  */
229 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
230     *range = hci_stack->le_connection_parameter_range;
231 }
232 
233 /**
234  * set le connection parameter range
235  *
236  */
237 
238 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
239     hci_stack->le_connection_parameter_range = *range;
240 }
241 
242 /**
243  * @brief Test if connection parameters are inside in existing rage
244  * @param conn_interval_min (unit: 1.25ms)
245  * @param conn_interval_max (unit: 1.25ms)
246  * @param conn_latency
247  * @param supervision_timeout (unit: 10ms)
248  * @returns 1 if included
249  */
250 int gap_connection_parameter_range_included(le_connection_parameter_range_t * existing_range, uint16_t le_conn_interval_min, uint16_t le_conn_interval_max, uint16_t le_conn_latency, uint16_t le_supervision_timeout){
251     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
252     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
253 
254     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
255     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
256 
257     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
258     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
259 
260     return 1;
261 }
262 
263 /**
264  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
265  * @note: default: 1
266  * @param max_peripheral_connections
267  */
268 #ifdef ENABLE_LE_PERIPHERAL
269 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
270     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
271 }
272 #endif
273 
274 /**
275  * get hci connections iterator
276  *
277  * @return hci connections iterator
278  */
279 
280 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
281     btstack_linked_list_iterator_init(it, &hci_stack->connections);
282 }
283 
284 /**
285  * get connection for a given handle
286  *
287  * @return connection OR NULL, if not found
288  */
289 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
290     btstack_linked_list_iterator_t it;
291     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
292     while (btstack_linked_list_iterator_has_next(&it)){
293         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
294         if ( item->con_handle == con_handle ) {
295             return item;
296         }
297     }
298     return NULL;
299 }
300 
301 /**
302  * get connection for given address
303  *
304  * @return connection OR NULL, if not found
305  */
306 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
307     btstack_linked_list_iterator_t it;
308     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
309     while (btstack_linked_list_iterator_has_next(&it)){
310         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
311         if (connection->address_type != addr_type)  continue;
312         if (memcmp(addr, connection->address, 6) != 0) continue;
313         return connection;
314     }
315     return NULL;
316 }
317 
318 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
319     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
320 }
321 
322 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
323     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
324 }
325 
326 #ifdef ENABLE_CLASSIC
327 
328 #ifdef ENABLE_SCO_OVER_HCI
329 static int hci_number_sco_connections(void){
330     int connections = 0;
331     btstack_linked_list_iterator_t it;
332     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
333     while (btstack_linked_list_iterator_has_next(&it)){
334         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
335         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
336         connections++;
337     }
338     return connections;
339 }
340 #endif
341 
342 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
343     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
344 #ifdef HAVE_EMBEDDED_TICK
345     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
346         // connections might be timed out
347         hci_emit_l2cap_check_timeout(connection);
348     }
349 #else
350     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
351         // connections might be timed out
352         hci_emit_l2cap_check_timeout(connection);
353     }
354 #endif
355 }
356 
357 static void hci_connection_timestamp(hci_connection_t *connection){
358 #ifdef HAVE_EMBEDDED_TICK
359     connection->timestamp = btstack_run_loop_embedded_get_ticks();
360 #else
361     connection->timestamp = btstack_run_loop_get_time_ms();
362 #endif
363 }
364 
365 /**
366  * add authentication flags and reset timer
367  * @note: assumes classic connection
368  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
369  */
370 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
371     bd_addr_t addr;
372     reverse_bd_addr(bd_addr, addr);
373     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
374     if (conn) {
375         connectionSetAuthenticationFlags(conn, flags);
376         hci_connection_timestamp(conn);
377     }
378 }
379 
380 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
381     hci_connection_t * conn = hci_connection_for_handle(handle);
382     if (!conn) return 0;
383     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
384     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
385     return 0;
386 }
387 
388 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
389     if (!hci_stack->link_key_db) return;
390     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
391     hci_stack->link_key_db->delete_link_key(addr);
392 }
393 
394 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
395     if (!hci_stack->link_key_db) return;
396     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
397     hci_stack->link_key_db->put_link_key(addr, link_key, type);
398 }
399 
400 void gap_delete_all_link_keys(void){
401     bd_addr_t  addr;
402     link_key_t link_key;
403     link_key_type_t type;
404     btstack_link_key_iterator_t it;
405     int ok = gap_link_key_iterator_init(&it);
406     if (!ok) {
407         log_error("could not initialize iterator");
408         return;
409     }
410     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
411         gap_drop_link_key_for_bd_addr(addr);
412     }
413     gap_link_key_iterator_done(&it);
414 }
415 
416 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
417     if (!hci_stack->link_key_db) return 0;
418     if (!hci_stack->link_key_db->iterator_init) return 0;
419     return hci_stack->link_key_db->iterator_init(it);
420 }
421 int gap_link_key_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * type){
422     if (!hci_stack->link_key_db) return 0;
423     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
424 }
425 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
426     if (!hci_stack->link_key_db) return;
427     hci_stack->link_key_db->iterator_done(it);
428 }
429 #endif
430 
431 static int hci_is_le_connection(hci_connection_t * connection){
432     switch (connection->address_type){
433         case BD_ADDR_TYPE_LE_PUBLIC:
434         case BD_ADDR_TYPE_LE_RANDOM:
435         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
436         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
437             return 1;
438         default:
439             return 0;
440     }
441 }
442 
443 /**
444  * count connections
445  */
446 static int nr_hci_connections(void){
447     int count = 0;
448     btstack_linked_item_t *it;
449     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
450         count++;
451     }
452     return count;
453 }
454 
455 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
456 
457     unsigned int num_packets_sent_classic = 0;
458     unsigned int num_packets_sent_le = 0;
459 
460     btstack_linked_item_t *it;
461     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
462         hci_connection_t * connection = (hci_connection_t *) it;
463         if (hci_is_le_connection(connection)){
464             num_packets_sent_le += connection->num_packets_sent;
465         }
466         if (connection->address_type == BD_ADDR_TYPE_ACL){
467             num_packets_sent_classic += connection->num_packets_sent;
468         }
469     }
470     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
471     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
472     int free_slots_le = 0;
473 
474     if (free_slots_classic < 0){
475         log_error("hci_number_free_acl_slots: outgoing classic packets (%u) > total classic packets (%u)", num_packets_sent_classic, hci_stack->acl_packets_total_num);
476         return 0;
477     }
478 
479     if (hci_stack->le_acl_packets_total_num){
480         // if we have LE slots, they are used
481         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
482         if (free_slots_le < 0){
483             log_error("hci_number_free_acl_slots: outgoing le packets (%u) > total le packets (%u)", num_packets_sent_le, hci_stack->le_acl_packets_total_num);
484             return 0;
485         }
486     } else {
487         // otherwise, classic slots are used for LE, too
488         free_slots_classic -= num_packets_sent_le;
489         if (free_slots_classic < 0){
490             log_error("hci_number_free_acl_slots: outgoing classic + le packets (%u + %u) > total packets (%u)", num_packets_sent_classic, num_packets_sent_le, hci_stack->acl_packets_total_num);
491             return 0;
492         }
493     }
494 
495     switch (address_type){
496         case BD_ADDR_TYPE_UNKNOWN:
497             log_error("hci_number_free_acl_slots: unknown address type");
498             return 0;
499 
500         case BD_ADDR_TYPE_ACL:
501             return free_slots_classic;
502 
503         default:
504            if (hci_stack->le_acl_packets_total_num){
505                return free_slots_le;
506            }
507            return free_slots_classic;
508     }
509 }
510 
511 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
512     // get connection type
513     hci_connection_t * connection = hci_connection_for_handle(con_handle);
514     if (!connection){
515         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
516         return 0;
517     }
518     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
519 }
520 
521 #ifdef ENABLE_CLASSIC
522 static int hci_number_free_sco_slots(void){
523     unsigned int num_sco_packets_sent  = 0;
524     btstack_linked_item_t *it;
525     if (hci_stack->synchronous_flow_control_enabled){
526         // explicit flow control
527         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
528             hci_connection_t * connection = (hci_connection_t *) it;
529             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
530             num_sco_packets_sent += connection->num_packets_sent;
531         }
532         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
533             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
534             return 0;
535         }
536         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
537     } else {
538         // implicit flow control -- TODO
539         int num_ready = 0;
540         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
541             hci_connection_t * connection = (hci_connection_t *) it;
542             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
543             if (connection->sco_tx_ready == 0) continue;
544             num_ready++;
545         }
546         return num_ready;
547     }
548 }
549 #endif
550 
551 // only used to send HCI Host Number Completed Packets
552 static int hci_can_send_comand_packet_transport(void){
553     if (hci_stack->hci_packet_buffer_reserved) return 0;
554 
555     // check for async hci transport implementations
556     if (hci_stack->hci_transport->can_send_packet_now){
557         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
558             return 0;
559         }
560     }
561     return 1;
562 }
563 
564 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
565 int hci_can_send_command_packet_now(void){
566     if (hci_can_send_comand_packet_transport() == 0) return 0;
567     return hci_stack->num_cmd_packets > 0;
568 }
569 
570 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
571     // check for async hci transport implementations
572     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
573     return hci_stack->hci_transport->can_send_packet_now(packet_type);
574 }
575 
576 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
577     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
578     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
579 }
580 
581 int hci_can_send_acl_le_packet_now(void){
582     if (hci_stack->hci_packet_buffer_reserved) return 0;
583     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
584 }
585 
586 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
587     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
588     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
589 }
590 
591 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
592     if (hci_stack->hci_packet_buffer_reserved) return 0;
593     return hci_can_send_prepared_acl_packet_now(con_handle);
594 }
595 
596 #ifdef ENABLE_CLASSIC
597 int hci_can_send_acl_classic_packet_now(void){
598     if (hci_stack->hci_packet_buffer_reserved) return 0;
599     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
600 }
601 
602 int hci_can_send_prepared_sco_packet_now(void){
603     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
604     if (hci_have_usb_transport()){
605         return hci_stack->sco_can_send_now;
606     } else {
607         return hci_number_free_sco_slots() > 0;
608     }
609 }
610 
611 int hci_can_send_sco_packet_now(void){
612     if (hci_stack->hci_packet_buffer_reserved) return 0;
613     return hci_can_send_prepared_sco_packet_now();
614 }
615 
616 void hci_request_sco_can_send_now_event(void){
617     hci_stack->sco_waiting_for_can_send_now = 1;
618     hci_notify_if_sco_can_send_now();
619 }
620 #endif
621 
622 // used for internal checks in l2cap.c
623 int hci_is_packet_buffer_reserved(void){
624     return hci_stack->hci_packet_buffer_reserved;
625 }
626 
627 // reserves outgoing packet buffer. @returns 1 if successful
628 int hci_reserve_packet_buffer(void){
629     if (hci_stack->hci_packet_buffer_reserved) {
630         log_error("hci_reserve_packet_buffer called but buffer already reserved");
631         return 0;
632     }
633     hci_stack->hci_packet_buffer_reserved = 1;
634     return 1;
635 }
636 
637 void hci_release_packet_buffer(void){
638     hci_stack->hci_packet_buffer_reserved = 0;
639 }
640 
641 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
642 static int hci_transport_synchronous(void){
643     return hci_stack->hci_transport->can_send_packet_now == NULL;
644 }
645 
646 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
647 
648     // log_info("hci_send_acl_packet_fragments  %u/%u (con 0x%04x)", hci_stack->acl_fragmentation_pos, hci_stack->acl_fragmentation_total_size, connection->con_handle);
649 
650     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
651     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
652     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0)){
653         max_acl_data_packet_length = hci_stack->le_data_packets_length;
654     }
655 
656 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
657     if (hci_is_le_connection(connection)){
658         max_acl_data_packet_length = connection->le_max_tx_octets;
659     }
660 #endif
661 
662     log_debug("hci_send_acl_packet_fragments entered");
663 
664     int err;
665     // multiple packets could be send on a synchronous HCI transport
666     while (true){
667 
668         log_debug("hci_send_acl_packet_fragments loop entered");
669 
670         // get current data
671         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
672         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
673         int more_fragments = 0;
674 
675         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
676         if (current_acl_data_packet_length > max_acl_data_packet_length){
677             more_fragments = 1;
678             current_acl_data_packet_length = max_acl_data_packet_length;
679         }
680 
681         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
682         if (acl_header_pos > 0){
683             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
684             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
685             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
686         }
687 
688         // update header len
689         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
690 
691         // count packet
692         connection->num_packets_sent++;
693         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
694 
695         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
696         if (more_fragments){
697             // update start of next fragment to send
698             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
699         } else {
700             // done
701             hci_stack->acl_fragmentation_pos = 0;
702             hci_stack->acl_fragmentation_total_size = 0;
703         }
704 
705         // send packet
706         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
707         const int size = current_acl_data_packet_length + 4;
708         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
709         hci_stack->acl_fragmentation_tx_active = 1;
710         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
711 
712         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
713 
714         // done yet?
715         if (!more_fragments) break;
716 
717         // can send more?
718         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
719     }
720 
721     log_debug("hci_send_acl_packet_fragments loop over");
722 
723     // release buffer now for synchronous transport
724     if (hci_transport_synchronous()){
725         hci_stack->acl_fragmentation_tx_active = 0;
726         hci_release_packet_buffer();
727         hci_emit_transport_packet_sent();
728     }
729 
730     return err;
731 }
732 
733 // pre: caller has reserved the packet buffer
734 int hci_send_acl_packet_buffer(int size){
735 
736     // log_info("hci_send_acl_packet_buffer size %u", size);
737 
738     if (!hci_stack->hci_packet_buffer_reserved) {
739         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
740         return 0;
741     }
742 
743     uint8_t * packet = hci_stack->hci_packet_buffer;
744     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
745 
746     // check for free places on Bluetooth module
747     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
748         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
749         hci_release_packet_buffer();
750         hci_emit_transport_packet_sent();
751         return BTSTACK_ACL_BUFFERS_FULL;
752     }
753 
754     hci_connection_t *connection = hci_connection_for_handle( con_handle);
755     if (!connection) {
756         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
757         hci_release_packet_buffer();
758         hci_emit_transport_packet_sent();
759         return 0;
760     }
761 
762 #ifdef ENABLE_CLASSIC
763     hci_connection_timestamp(connection);
764 #endif
765 
766     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
767 
768     // setup data
769     hci_stack->acl_fragmentation_total_size = size;
770     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
771 
772     return hci_send_acl_packet_fragments(connection);
773 }
774 
775 #ifdef ENABLE_CLASSIC
776 // pre: caller has reserved the packet buffer
777 int hci_send_sco_packet_buffer(int size){
778 
779     // log_info("hci_send_acl_packet_buffer size %u", size);
780 
781     if (!hci_stack->hci_packet_buffer_reserved) {
782         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
783         return 0;
784     }
785 
786     uint8_t * packet = hci_stack->hci_packet_buffer;
787 
788     // skip checks in loopback mode
789     if (!hci_stack->loopback_mode){
790         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
791 
792         // check for free places on Bluetooth module
793         if (!hci_can_send_prepared_sco_packet_now()) {
794             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
795             hci_release_packet_buffer();
796             hci_emit_transport_packet_sent();
797             return BTSTACK_ACL_BUFFERS_FULL;
798         }
799 
800         // track send packet in connection struct
801         hci_connection_t *connection = hci_connection_for_handle( con_handle);
802         if (!connection) {
803             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
804             hci_release_packet_buffer();
805             hci_emit_transport_packet_sent();
806             return 0;
807         }
808 
809         if (hci_have_usb_transport()){
810             // token used
811             hci_stack->sco_can_send_now = 0;
812         } else {
813             if (hci_stack->synchronous_flow_control_enabled){
814                 connection->num_packets_sent++;
815             } else {
816                 connection->sco_tx_ready--;
817             }
818         }
819     }
820 
821     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
822     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
823 
824     if (hci_transport_synchronous()){
825         hci_release_packet_buffer();
826         hci_emit_transport_packet_sent();
827     }
828 
829     return err;
830 }
831 #endif
832 
833 static void acl_handler(uint8_t *packet, int size){
834 
835     // log_info("acl_handler: size %u", size);
836 
837     // get info
838     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
839     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
840     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
841     uint16_t acl_length         = READ_ACL_LENGTH(packet);
842 
843     // ignore non-registered handle
844     if (!conn){
845         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
846         return;
847     }
848 
849     // assert packet is complete
850     if ((acl_length + 4) != size){
851         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
852         return;
853     }
854 
855 #ifdef ENABLE_CLASSIC
856     // update idle timestamp
857     hci_connection_timestamp(conn);
858 #endif
859 
860 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
861     hci_stack->host_completed_packets = 1;
862     conn->num_packets_completed++;
863 #endif
864 
865     // handle different packet types
866     switch (acl_flags & 0x03) {
867 
868         case 0x01: // continuation fragment
869 
870             // sanity checks
871             if (conn->acl_recombination_pos == 0) {
872                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
873                 return;
874             }
875             if ((conn->acl_recombination_pos + acl_length) > (4 + HCI_ACL_BUFFER_SIZE)){
876                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
877                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
878                 conn->acl_recombination_pos = 0;
879                 return;
880             }
881 
882             // append fragment payload (header already stored)
883             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
884                          &packet[4], acl_length);
885             conn->acl_recombination_pos += acl_length;
886 
887             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
888             //        conn->acl_recombination_pos, conn->acl_recombination_length);
889 
890             // forward complete L2CAP packet if complete.
891             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4 + 4)){ // pos already incl. ACL header
892                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
893                 // reset recombination buffer
894                 conn->acl_recombination_length = 0;
895                 conn->acl_recombination_pos = 0;
896             }
897             break;
898 
899         case 0x02: { // first fragment
900 
901             // sanity check
902             if (conn->acl_recombination_pos) {
903                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
904                 conn->acl_recombination_pos = 0;
905             }
906 
907             // peek into L2CAP packet!
908             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
909 
910             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
911 
912             // compare fragment size to L2CAP packet size
913             if (acl_length >= (l2cap_length + 4)){
914                 // forward fragment as L2CAP packet
915                 hci_emit_acl_packet(packet, acl_length + 4);
916             } else {
917 
918                 if (acl_length > HCI_ACL_BUFFER_SIZE){
919                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
920                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
921                     return;
922                 }
923 
924                 // store first fragment and tweak acl length for complete package
925                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
926                              packet, acl_length + 4);
927                 conn->acl_recombination_pos    = acl_length + 4;
928                 conn->acl_recombination_length = l2cap_length;
929                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
930             }
931             break;
932 
933         }
934         default:
935             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
936             return;
937     }
938 
939     // execute main loop
940     hci_run();
941 }
942 
943 static void hci_shutdown_connection(hci_connection_t *conn){
944     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
945 
946 #ifdef ENABLE_CLASSIC
947 #ifdef ENABLE_SCO_OVER_HCI
948     int addr_type = conn->address_type;
949 #endif
950 #endif
951 
952     btstack_run_loop_remove_timer(&conn->timeout);
953 
954     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
955     btstack_memory_hci_connection_free( conn );
956 
957     // now it's gone
958     hci_emit_nr_connections_changed();
959 
960 #ifdef ENABLE_CLASSIC
961 #ifdef ENABLE_SCO_OVER_HCI
962     // update SCO
963     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
964         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
965     }
966 #endif
967 #endif
968 }
969 
970 #ifdef ENABLE_CLASSIC
971 
972 static const uint16_t packet_type_sizes[] = {
973     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
974     HCI_ACL_DH1_SIZE, 0, 0, 0,
975     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
976     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
977 };
978 static const uint8_t  packet_type_feature_requirement_bit[] = {
979      0, // 3 slot packets
980      1, // 5 slot packets
981     25, // EDR 2 mpbs
982     26, // EDR 3 mbps
983     39, // 3 slot EDR packts
984     40, // 5 slot EDR packet
985 };
986 static const uint16_t packet_type_feature_packet_mask[] = {
987     0x0f00, // 3 slot packets
988     0xf000, // 5 slot packets
989     0x1102, // EDR 2 mpbs
990     0x2204, // EDR 3 mbps
991     0x0300, // 3 slot EDR packts
992     0x3000, // 5 slot EDR packet
993 };
994 
995 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
996     // enable packet types based on size
997     uint16_t packet_types = 0;
998     unsigned int i;
999     for (i=0;i<16;i++){
1000         if (packet_type_sizes[i] == 0) continue;
1001         if (packet_type_sizes[i] <= buffer_size){
1002             packet_types |= 1 << i;
1003         }
1004     }
1005     // disable packet types due to missing local supported features
1006     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1007         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1008         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1009         if (feature_set) continue;
1010         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1011         packet_types &= ~packet_type_feature_packet_mask[i];
1012     }
1013     // flip bits for "may not be used"
1014     packet_types ^= 0x3306;
1015     return packet_types;
1016 }
1017 
1018 uint16_t hci_usable_acl_packet_types(void){
1019     return hci_stack->packet_types;
1020 }
1021 #endif
1022 
1023 uint8_t* hci_get_outgoing_packet_buffer(void){
1024     // hci packet buffer is >= acl data packet length
1025     return hci_stack->hci_packet_buffer;
1026 }
1027 
1028 uint16_t hci_max_acl_data_packet_length(void){
1029     return hci_stack->acl_data_packet_length;
1030 }
1031 
1032 #ifdef ENABLE_CLASSIC
1033 int hci_extended_sco_link_supported(void){
1034     // No. 31, byte 3, bit 7
1035     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1036 }
1037 #endif
1038 
1039 int hci_non_flushable_packet_boundary_flag_supported(void){
1040     // No. 54, byte 6, bit 6
1041     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1042 }
1043 
1044 static int gap_ssp_supported(void){
1045     // No. 51, byte 6, bit 3
1046     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1047 }
1048 
1049 static int hci_classic_supported(void){
1050 #ifdef ENABLE_CLASSIC
1051     // No. 37, byte 4, bit 5, = No BR/EDR Support
1052     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1053 #else
1054     return 0;
1055 #endif
1056 }
1057 
1058 static int hci_le_supported(void){
1059 #ifdef ENABLE_BLE
1060     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1061     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1062 #else
1063     return 0;
1064 #endif
1065 }
1066 
1067 #ifdef ENABLE_BLE
1068 
1069 /**
1070  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1071  */
1072 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1073     *addr_type = hci_stack->le_own_addr_type;
1074     if (hci_stack->le_own_addr_type){
1075         (void)memcpy(addr, hci_stack->le_random_address, 6);
1076     } else {
1077         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1078     }
1079 }
1080 
1081 #ifdef ENABLE_LE_CENTRAL
1082 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1083 
1084     int offset = 3;
1085     int num_reports = packet[offset];
1086     offset += 1;
1087 
1088     int i;
1089     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1090     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1091     for (i=0; (i<num_reports) && (offset < size);i++){
1092         // sanity checks on data_length:
1093         uint8_t data_length = packet[offset + 8];
1094         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1095         if ((offset + 9 + data_length + 1) > size)    return;
1096         // setup event
1097         uint8_t event_size = 10 + data_length;
1098         int pos = 0;
1099         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1100         event[pos++] = event_size;
1101         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1102         offset += 8;
1103         pos += 8;
1104         event[pos++] = packet[offset + 1 + data_length]; // rssi
1105         event[pos++] = data_length;
1106         offset++;
1107         (void)memcpy(&event[pos], &packet[offset], data_length);
1108         pos +=    data_length;
1109         offset += data_length + 1; // rssi
1110         hci_emit_event(event, pos, 1);
1111     }
1112 }
1113 #endif
1114 #endif
1115 
1116 #ifdef ENABLE_BLE
1117 #ifdef ENABLE_LE_PERIPHERAL
1118 static void hci_reenable_advertisements_if_needed(void){
1119     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1120         // get number of active le slave connections
1121         int num_slave_connections = 0;
1122         btstack_linked_list_iterator_t it;
1123         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1124         while (btstack_linked_list_iterator_has_next(&it)){
1125             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1126             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1127             if (con->state != OPEN) continue;
1128             if (con->role  != HCI_ROLE_SLAVE) continue;
1129             if (!hci_is_le_connection(con)) continue;
1130             num_slave_connections++;
1131         }
1132         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1133         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1134             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1135         }
1136     }
1137 }
1138 #endif
1139 #endif
1140 
1141 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1142 
1143 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1144     if (!hci_stack->config) return 0;
1145     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1146     // Limit baud rate for Broadcom chipsets to 3 mbps
1147     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1148         baud_rate = 3000000;
1149     }
1150     return baud_rate;
1151 }
1152 
1153 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1154     UNUSED(ds);
1155 
1156     switch (hci_stack->substate){
1157         case HCI_INIT_W4_SEND_RESET:
1158             log_info("Resend HCI Reset");
1159             hci_stack->substate = HCI_INIT_SEND_RESET;
1160             hci_stack->num_cmd_packets = 1;
1161             hci_run();
1162             break;
1163         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1164             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1165             if (hci_stack->hci_transport->reset_link){
1166                 hci_stack->hci_transport->reset_link();
1167             }
1168 
1169             /* fall through */
1170 
1171         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1172             log_info("Resend HCI Reset - CSR Warm Boot");
1173             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1174             hci_stack->num_cmd_packets = 1;
1175             hci_run();
1176             break;
1177         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1178             if (hci_stack->hci_transport->set_baudrate){
1179                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1180                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1181                 hci_stack->hci_transport->set_baudrate(baud_rate);
1182             }
1183             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1184             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1185                 if (hci_stack->hci_transport->reset_link){
1186                     log_info("Link Reset");
1187                     hci_stack->hci_transport->reset_link();
1188                 }
1189                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1190                 hci_run();
1191             }
1192             break;
1193         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1194             // otherwise continue
1195             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1196             hci_send_cmd(&hci_read_local_supported_commands);
1197             break;
1198         default:
1199             break;
1200     }
1201 }
1202 #endif
1203 
1204 static void hci_initializing_next_state(void){
1205     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1206 }
1207 
1208 // assumption: hci_can_send_command_packet_now() == true
1209 static void hci_initializing_run(void){
1210     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1211     switch (hci_stack->substate){
1212         case HCI_INIT_SEND_RESET:
1213             hci_state_reset();
1214 
1215 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1216             // prepare reset if command complete not received in 100ms
1217             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1218             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1219             btstack_run_loop_add_timer(&hci_stack->timeout);
1220 #endif
1221             // send command
1222             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1223             hci_send_cmd(&hci_reset);
1224             break;
1225         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1226             hci_send_cmd(&hci_read_local_version_information);
1227             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1228             break;
1229         case HCI_INIT_SEND_READ_LOCAL_NAME:
1230             hci_send_cmd(&hci_read_local_name);
1231             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1232             break;
1233 
1234 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1235         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1236             hci_state_reset();
1237             // prepare reset if command complete not received in 100ms
1238             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1239             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1240             btstack_run_loop_add_timer(&hci_stack->timeout);
1241             // send command
1242             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1243             hci_send_cmd(&hci_reset);
1244             break;
1245         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1246             hci_state_reset();
1247             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1248             hci_send_cmd(&hci_reset);
1249             break;
1250         case HCI_INIT_SEND_BAUD_CHANGE: {
1251             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1252             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1253             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1254             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1255             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1256             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1257             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1258             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1259                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1260                 btstack_run_loop_add_timer(&hci_stack->timeout);
1261             }
1262             break;
1263         }
1264         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1265             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1266             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1267             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1268             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1269             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1270             break;
1271         }
1272         case HCI_INIT_CUSTOM_INIT:
1273             // Custom initialization
1274             if (hci_stack->chipset && hci_stack->chipset->next_command){
1275                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1276                 int send_cmd = 0;
1277                 switch (hci_stack->chipset_result){
1278                     case BTSTACK_CHIPSET_VALID_COMMAND:
1279                         send_cmd = 1;
1280                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1281                         break;
1282                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1283                         send_cmd = 1;
1284                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1285                         log_info("CSR Warm Boot");
1286                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1287                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1288                         btstack_run_loop_add_timer(&hci_stack->timeout);
1289                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1290                             && hci_stack->config
1291                             && hci_stack->chipset
1292                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1293                             && hci_stack->hci_transport->set_baudrate
1294                             && hci_transport_uart_get_main_baud_rate()){
1295                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1296                         } else {
1297                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1298                         }
1299                         break;
1300                     default:
1301                         break;
1302                 }
1303 
1304                 if (send_cmd){
1305                     int size = 3 + hci_stack->hci_packet_buffer[2];
1306                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1307                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1308                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1309                     break;
1310                 }
1311                 log_info("Init script done");
1312 
1313                 // Init script download on Broadcom chipsets causes:
1314                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1315                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1316                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1317 
1318                     // - baud rate to reset, restore UART baud rate if needed
1319                     int need_baud_change = hci_stack->config
1320                         && hci_stack->chipset
1321                         && hci_stack->chipset->set_baudrate_command
1322                         && hci_stack->hci_transport->set_baudrate
1323                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1324                     if (need_baud_change) {
1325                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1326                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1327                         hci_stack->hci_transport->set_baudrate(baud_rate);
1328                     }
1329 
1330                     uint16_t bcm_delay_ms = 300;
1331                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1332                     //   -> Work around: wait here.
1333                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1334                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1335                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1336                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1337                     btstack_run_loop_add_timer(&hci_stack->timeout);
1338                     break;
1339                 }
1340             }
1341             // otherwise continue
1342             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1343             hci_send_cmd(&hci_read_local_supported_commands);
1344             break;
1345         case HCI_INIT_SET_BD_ADDR:
1346             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1347             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1348             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1349             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1350             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1351             break;
1352 #endif
1353 
1354         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1355             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1356             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1357             hci_send_cmd(&hci_read_local_supported_commands);
1358             break;
1359         case HCI_INIT_READ_BD_ADDR:
1360             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1361             hci_send_cmd(&hci_read_bd_addr);
1362             break;
1363         case HCI_INIT_READ_BUFFER_SIZE:
1364             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1365             hci_send_cmd(&hci_read_buffer_size);
1366             break;
1367         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1368             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1369             hci_send_cmd(&hci_read_local_supported_features);
1370             break;
1371 
1372 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1373         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1374             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1375             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1376             break;
1377         case HCI_INIT_HOST_BUFFER_SIZE:
1378             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1379             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1380                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1381             break;
1382 #endif
1383 
1384         case HCI_INIT_SET_EVENT_MASK:
1385             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1386             if (hci_le_supported()){
1387                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1388             } else {
1389                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1390                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1391             }
1392             break;
1393 
1394 #ifdef ENABLE_CLASSIC
1395         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1396             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1397             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1398             break;
1399         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1400             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1401             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1402             break;
1403         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1404             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1405             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1406             break;
1407         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1408             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1409             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1410             break;
1411         case HCI_INIT_WRITE_LOCAL_NAME: {
1412             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1413             hci_reserve_packet_buffer();
1414             uint8_t * packet = hci_stack->hci_packet_buffer;
1415             // construct HCI Command and send
1416             uint16_t opcode = hci_write_local_name.opcode;
1417             hci_stack->last_cmd_opcode = opcode;
1418             packet[0] = opcode & 0xff;
1419             packet[1] = opcode >> 8;
1420             packet[2] = DEVICE_NAME_LEN;
1421             memset(&packet[3], 0, DEVICE_NAME_LEN);
1422             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1423             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1424             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1425             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1426             // expand '00:00:00:00:00:00' in name with bd_addr
1427             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1428             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1429             break;
1430         }
1431         case HCI_INIT_WRITE_EIR_DATA: {
1432             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1433             hci_reserve_packet_buffer();
1434             uint8_t * packet = hci_stack->hci_packet_buffer;
1435             // construct HCI Command in-place and send
1436             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1437             hci_stack->last_cmd_opcode = opcode;
1438             uint16_t offset = 0;
1439             packet[offset++] = opcode & 0xff;
1440             packet[offset++] = opcode >> 8;
1441             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1442             packet[offset++] = 0;  // FEC not required
1443             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1444             if (hci_stack->eir_data){
1445                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1446                 ad_context_t context;
1447                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1448                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1449                     uint8_t size        = ad_iterator_get_data_len(&context);
1450                     const uint8_t *data = ad_iterator_get_data(&context);
1451                     // copy item
1452                     packet[offset++] = size + 1;
1453                     packet[offset++] = data_type;
1454                     memcpy(&packet[offset], data, size);
1455                     // update name item
1456                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1457                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1458                     }
1459                     offset += size;
1460                 }
1461             } else {
1462                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1463                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1464                 packet[offset++] = bytes_to_copy + 1;
1465                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1466                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1467                 // expand '00:00:00:00:00:00' in name with bd_addr
1468                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1469             }
1470             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1471             break;
1472         }
1473         case HCI_INIT_WRITE_INQUIRY_MODE:
1474             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1475             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1476             break;
1477         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1478             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1479             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1480             break;
1481         case HCI_INIT_WRITE_SCAN_ENABLE:
1482             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1483             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1484             break;
1485         // only sent if ENABLE_SCO_OVER_HCI is defined
1486         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1487             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1488             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1489             break;
1490         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1491             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1492             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1493             break;
1494         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1495         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1496             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1497             log_info("BCM: Route SCO data via HCI transport");
1498             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1499             break;
1500 
1501 #endif
1502 #ifdef ENABLE_BLE
1503         // LE INIT
1504         case HCI_INIT_LE_READ_BUFFER_SIZE:
1505             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1506             hci_send_cmd(&hci_le_read_buffer_size);
1507             break;
1508         case HCI_INIT_LE_SET_EVENT_MASK:
1509             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1510             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1511             break;
1512         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1513             // LE Supported Host = 1, Simultaneous Host = 0
1514             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1515             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1516             break;
1517 #endif
1518 
1519 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1520         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1521             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1522             hci_send_cmd(&hci_le_read_maximum_data_length);
1523             break;
1524         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1525             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1526             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1527             break;
1528 #endif
1529 
1530 #ifdef ENABLE_LE_CENTRAL
1531         case HCI_INIT_READ_WHITE_LIST_SIZE:
1532             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1533             hci_send_cmd(&hci_le_read_white_list_size);
1534             break;
1535         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1536             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1537             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1538             hci_send_cmd(&hci_le_set_scan_parameters, 1, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
1539             break;
1540 #endif
1541         default:
1542             return;
1543     }
1544 }
1545 
1546 static void hci_init_done(void){
1547     // done. tell the app
1548     log_info("hci_init_done -> HCI_STATE_WORKING");
1549     hci_stack->state = HCI_STATE_WORKING;
1550     hci_emit_state();
1551     hci_run();
1552 }
1553 
1554 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1555     bool command_completed = false;
1556     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1557         uint16_t opcode = little_endian_read_16(packet,3);
1558         if (opcode == hci_stack->last_cmd_opcode){
1559             command_completed = true;
1560             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1561         } else {
1562             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1563         }
1564     }
1565 
1566     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1567         uint8_t  status = packet[2];
1568         uint16_t opcode = little_endian_read_16(packet,4);
1569         if (opcode == hci_stack->last_cmd_opcode){
1570             if (status){
1571                 command_completed = true;
1572                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1573             } else {
1574                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1575             }
1576         } else {
1577             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1578         }
1579     }
1580 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1581     // Vendor == CSR
1582     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1583         // TODO: track actual command
1584         command_completed = true;
1585     }
1586 
1587     // Vendor == Toshiba
1588     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1589         // TODO: track actual command
1590         command_completed = true;
1591         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1592         hci_stack->num_cmd_packets = 1;
1593     }
1594 #endif
1595 
1596     return command_completed;
1597 }
1598 
1599 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1600 
1601     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1602 
1603     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1604 
1605 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1606 
1607     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1608     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1609     //
1610     // HCI Reset
1611     // Timeout 100 ms
1612     // HCI Reset
1613     // Command Complete Reset
1614     // HCI Read Local Version Information
1615     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1616     // hang...
1617     //
1618     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1619     if (!command_completed
1620             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1621             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1622 
1623         uint16_t opcode = little_endian_read_16(packet,3);
1624         if (opcode == hci_reset.opcode){
1625             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1626             return;
1627         }
1628     }
1629 
1630     // CSR & H5
1631     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1632     if (!command_completed
1633             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1634             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1635 
1636         uint16_t opcode = little_endian_read_16(packet,3);
1637         if (opcode == hci_reset.opcode){
1638             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1639             return;
1640         }
1641     }
1642 
1643     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1644     // fix: Correct substate and behave as command below
1645     if (command_completed){
1646         switch (hci_stack->substate){
1647             case HCI_INIT_SEND_RESET:
1648                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1649                 break;
1650             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1651                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1652                 break;
1653             default:
1654                 break;
1655         }
1656     }
1657 
1658 #endif
1659 
1660     if (!command_completed) return;
1661 
1662     bool need_baud_change = false;
1663     bool need_addr_change = false;
1664 
1665 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1666     need_baud_change = hci_stack->config
1667                         && hci_stack->chipset
1668                         && hci_stack->chipset->set_baudrate_command
1669                         && hci_stack->hci_transport->set_baudrate
1670                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1671 
1672     need_addr_change = hci_stack->custom_bd_addr_set
1673                         && hci_stack->chipset
1674                         && hci_stack->chipset->set_bd_addr_command;
1675 #endif
1676 
1677     switch(hci_stack->substate){
1678 
1679 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1680         case HCI_INIT_SEND_RESET:
1681             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1682             // fix: just correct substate and behave as command below
1683             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1684             btstack_run_loop_remove_timer(&hci_stack->timeout);
1685             break;
1686         case HCI_INIT_W4_SEND_RESET:
1687             btstack_run_loop_remove_timer(&hci_stack->timeout);
1688             break;
1689         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1690             log_info("Received local name, need baud change %d", (int) need_baud_change);
1691             if (need_baud_change){
1692                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1693                 return;
1694             }
1695             // skip baud change
1696             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1697             return;
1698         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1699             // for STLC2500D, baud rate change already happened.
1700             // for others, baud rate gets changed now
1701             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1702                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1703                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1704                 hci_stack->hci_transport->set_baudrate(baud_rate);
1705             }
1706             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1707             return;
1708         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1709             btstack_run_loop_remove_timer(&hci_stack->timeout);
1710             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1711             return;
1712         case HCI_INIT_W4_CUSTOM_INIT:
1713             // repeat custom init
1714             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1715             return;
1716 #else
1717         case HCI_INIT_W4_SEND_RESET:
1718             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1719             return ;
1720 #endif
1721 
1722         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1723             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1724               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1725                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1726                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1727                 return;
1728             }
1729             if (need_addr_change){
1730                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1731                 return;
1732             }
1733             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1734             return;
1735 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1736         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1737             if (need_baud_change){
1738                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1739                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1740                 hci_stack->hci_transport->set_baudrate(baud_rate);
1741             }
1742             if (need_addr_change){
1743                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1744                 return;
1745             }
1746             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1747             return;
1748         case HCI_INIT_W4_SET_BD_ADDR:
1749             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1750             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1751             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1752                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1753                 return;
1754             }
1755             // skipping st warm boot
1756             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1757             return;
1758         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1759             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1760             return;
1761 #endif
1762         case HCI_INIT_W4_READ_BD_ADDR:
1763             // only read buffer size if supported
1764             if (hci_stack->local_supported_commands[0] & 0x01) {
1765                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1766                 return;
1767             }
1768             // skipping read buffer size
1769             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1770             return;
1771         case HCI_INIT_W4_SET_EVENT_MASK:
1772             // skip Classic init commands for LE only chipsets
1773             if (!hci_classic_supported()){
1774 #ifdef ENABLE_BLE
1775                 if (hci_le_supported()){
1776                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1777                     return;
1778                 }
1779 #endif
1780                 log_error("Neither BR/EDR nor LE supported");
1781                 hci_init_done();
1782                 return;
1783             }
1784             if (!gap_ssp_supported()){
1785                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1786                 return;
1787             }
1788             break;
1789 #ifdef ENABLE_BLE
1790         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1791             // skip write le host if not supported (e.g. on LE only EM9301)
1792             if (hci_stack->local_supported_commands[0] & 0x02) break;
1793             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1794             return;
1795 
1796 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1797         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1798             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1799             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1800                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1801                 return;
1802             }
1803             // explicit fall through to reduce repetitions
1804 
1805 #ifdef ENABLE_LE_CENTRAL
1806             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1807 #else
1808             hci_init_done();
1809 #endif
1810             return;
1811 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1812 
1813 #endif  /* ENABLE_BLE */
1814 
1815         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1816             // skip write secure connections host support if not supported or disabled
1817             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1] & 0x02) == 0) {
1818                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1819                 return;
1820             }
1821             break;
1822 
1823 #ifdef ENABLE_SCO_OVER_HCI
1824         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1825             // skip write synchronous flow control if not supported
1826             if (hci_stack->local_supported_commands[0] & 0x04) break;
1827             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1828 
1829             /* fall through */
1830 
1831         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1832             // skip write default erroneous data reporting if not supported
1833             if (hci_stack->local_supported_commands[0] & 0x08) break;
1834             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1835 
1836             /* fall through */
1837 
1838         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1839             // skip bcm set sco pcm config on non-Broadcom chipsets
1840             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1841             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1842 
1843             /* fall through */
1844 
1845         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1846             if (!hci_le_supported()){
1847                 // SKIP LE init for Classic only configuration
1848                 hci_init_done();
1849                 return;
1850             }
1851             break;
1852 
1853 #else /* !ENABLE_SCO_OVER_HCI */
1854 
1855         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1856 #ifdef ENABLE_BLE
1857             if (hci_le_supported()){
1858                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1859                 return;
1860             }
1861 #endif
1862             // SKIP LE init for Classic only configuration
1863             hci_init_done();
1864             return;
1865 #endif /* ENABLE_SCO_OVER_HCI */
1866 
1867 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1868 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1869         // Response to command before init done state -> init done
1870         case (HCI_INIT_DONE-1):
1871             hci_init_done();
1872             return;
1873 #endif
1874 
1875         default:
1876             break;
1877     }
1878     hci_initializing_next_state();
1879 }
1880 
1881 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1882     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1883     bd_addr_t bd_address;
1884     (void)memcpy(&bd_address, conn->address, 6);
1885 
1886 #ifdef ENABLE_CLASSIC
1887     // cache needed data
1888     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1889 #endif
1890 
1891     // connection failed, remove entry
1892     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1893     btstack_memory_hci_connection_free( conn );
1894 
1895 #ifdef ENABLE_CLASSIC
1896     // notify client if dedicated bonding
1897     if (notify_dedicated_bonding_failed){
1898         log_info("hci notify_dedicated_bonding_failed");
1899         hci_emit_dedicated_bonding_result(bd_address, status);
1900     }
1901 
1902     // if authentication error, also delete link key
1903     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1904         gap_drop_link_key_for_bd_addr(bd_address);
1905     }
1906 #endif
1907 }
1908 
1909 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1910     // SSP Controller
1911     if (features[6] & (1 << 3)){
1912         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1913     }
1914     // eSCO
1915     if (features[3] & (1<<7)){
1916         conn->remote_supported_features[0] |= 1;
1917     }
1918     // Extended features
1919     if (features[7] & (1<<7)){
1920         conn->remote_supported_features[0] |= 2;
1921     }
1922 }
1923 
1924 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1925     // SSP Host
1926     if (features[0] & (1 << 0)){
1927         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1928     }
1929     // SC Host
1930     if (features[0] & (1 << 3)){
1931         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1932     }
1933 }
1934 
1935 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1936     // SC Controller
1937     if (features[1] & (1 << 0)){
1938         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1939     }
1940 }
1941 
1942 static void hci_handle_remote_features_received(hci_connection_t * conn){
1943     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1944     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1945     if (conn->bonding_flags & BONDING_DEDICATED){
1946         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1947     }
1948 }
1949 
1950 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1951     // handle BT initialization
1952     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1953         hci_initializing_event_handler(packet, size);
1954     }
1955 
1956     // help with BT sleep
1957     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1958         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1959         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1960         hci_initializing_next_state();
1961     }
1962 }
1963 
1964 static void event_handler(uint8_t *packet, int size){
1965 
1966     uint16_t event_length = packet[1];
1967 
1968     // assert packet is complete
1969     if (size != (event_length + 2)){
1970         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1971         return;
1972     }
1973 
1974     bd_addr_t addr;
1975     bd_addr_type_t addr_type;
1976     hci_con_handle_t handle;
1977     hci_connection_t * conn;
1978     int i;
1979     int create_connection_cmd;
1980 
1981 #ifdef ENABLE_CLASSIC
1982     uint8_t link_type;
1983 #endif
1984 
1985     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1986 
1987     switch (hci_event_packet_get_type(packet)) {
1988 
1989         case HCI_EVENT_COMMAND_COMPLETE:
1990             // get num cmd packets - limit to 1 to reduce complexity
1991             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1992 
1993             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1994                 if (packet[5]) break;
1995                 // terminate, name 248 chars
1996                 packet[6+248] = 0;
1997                 log_info("local name: %s", &packet[6]);
1998             }
1999             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
2000                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2001                 if (hci_stack->state == HCI_STATE_INITIALIZING){
2002                     uint16_t acl_len = little_endian_read_16(packet, 6);
2003                     uint16_t sco_len = packet[8];
2004 
2005                     // determine usable ACL/SCO payload size
2006                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2007                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2008 
2009                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
2010                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
2011 
2012                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2013                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2014                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2015                 }
2016             }
2017             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
2018                 if (packet[5] == 0){
2019                     uint8_t event[5];
2020                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2021                     event[1] = 3;
2022                     (void)memcpy(&event[2], &packet[6], 3);
2023                     hci_emit_event(event, sizeof(event), 1);
2024                 }
2025             }
2026 #ifdef ENABLE_BLE
2027             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
2028                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2029                 hci_stack->le_acl_packets_total_num  = packet[8];
2030                 // determine usable ACL payload size
2031                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2032                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2033                 }
2034                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2035             }
2036 #endif
2037 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2038             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
2039                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2040                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2041                 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);
2042             }
2043 #endif
2044 #ifdef ENABLE_LE_CENTRAL
2045             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
2046                 hci_stack->le_whitelist_capacity = packet[6];
2047                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2048             }
2049 #endif
2050             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
2051                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2052 				hci_stack->local_bd_addr);
2053                 log_info("Local Address, Status: 0x%02x: Addr: %s",
2054                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2055 #ifdef ENABLE_CLASSIC
2056                 if (hci_stack->link_key_db){
2057                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2058                 }
2059 #endif
2060             }
2061 #ifdef ENABLE_CLASSIC
2062             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2063                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2064             }
2065             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2066                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2067                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2068                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2069                     hci_emit_event(event, sizeof(event), 1);
2070                 }
2071             }
2072 #endif
2073 
2074             // Note: HCI init checks
2075             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2076                 (void)memcpy(hci_stack->local_supported_features,
2077 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2078 			     8);
2079 
2080 #ifdef ENABLE_CLASSIC
2081                 // determine usable ACL packet types based on host buffer size and supported features
2082                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2083                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2084 #endif
2085                 // Classic/LE
2086                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2087             }
2088             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2089                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2090                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2091                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2092                 // map Cypress to Broadcom
2093                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2094                     log_info("Treat Cypress as Broadcom");
2095                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2096                     little_endian_store_16(packet, 10, manufacturer);
2097                 }
2098                 hci_stack->manufacturer = manufacturer;
2099                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2100                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2101                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2102             }
2103             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2104                 hci_stack->local_supported_commands[0] =
2105                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2106                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2107                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2108                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2109                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2110                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2111                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2112                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2113                 hci_stack->local_supported_commands[1] =
2114                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+ 2] & 0x40) >> 6) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2115                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+32] & 0x08) >> 2);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2116                 log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2117             }
2118 #ifdef ENABLE_CLASSIC
2119             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2120                 if (packet[5] == 0){
2121                     hci_stack->synchronous_flow_control_enabled = 1;
2122                 }
2123             }
2124             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2125                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2126                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2127                 conn   = hci_connection_for_handle(handle);
2128                 if (!conn) break;
2129                 if (status == 0){
2130                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2131                     log_info("Handle %x04x key Size: %u", handle, key_size);
2132                     conn->encryption_key_size = key_size;
2133                 } else {
2134                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2135                     conn->encryption_key_size = 1;
2136                 }
2137                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2138                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2139             }
2140 #endif
2141             break;
2142 
2143         case HCI_EVENT_COMMAND_STATUS:
2144             // get num cmd packets - limit to 1 to reduce complexity
2145             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2146 
2147             // check command status to detected failed outgoing connections
2148             create_connection_cmd = 0;
2149 #ifdef ENABLE_CLASSIC
2150             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2151                 create_connection_cmd = 1;
2152             }
2153 #endif
2154 #ifdef ENABLE_LE_CENTRAL
2155             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2156                 create_connection_cmd = 1;
2157             }
2158 #endif
2159             if (create_connection_cmd) {
2160                 uint8_t status = hci_event_command_status_get_status(packet);
2161                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2162                 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);
2163 
2164                 // reset outgoing address info
2165                 memset(hci_stack->outgoing_addr, 0, 6);
2166                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2167 
2168                 // error => outgoing connection failed
2169                 if ((conn != NULL) && (status != 0)){
2170                     hci_handle_connection_failed(conn, status);
2171                 }
2172             }
2173             break;
2174 
2175         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2176             if (size < 3) return;
2177             uint16_t num_handles = packet[2];
2178             if (size != (3 + num_handles * 4)) return;
2179             uint16_t offset = 3;
2180             for (i=0; i<num_handles;i++){
2181                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2182                 offset += 2;
2183                 uint16_t num_packets = little_endian_read_16(packet, offset);
2184                 offset += 2;
2185 
2186                 conn = hci_connection_for_handle(handle);
2187                 if (!conn){
2188                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2189                     continue;
2190                 }
2191 
2192                 if (conn->num_packets_sent >= num_packets){
2193                     conn->num_packets_sent -= num_packets;
2194                 } else {
2195                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2196                     conn->num_packets_sent = 0;
2197                 }
2198                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2199 
2200 #ifdef ENABLE_CLASSIC
2201                 // For SCO, we do the can_send_now_check here
2202                 hci_notify_if_sco_can_send_now();
2203 #endif
2204             }
2205             break;
2206         }
2207 
2208 #ifdef ENABLE_CLASSIC
2209         case HCI_EVENT_INQUIRY_COMPLETE:
2210             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2211                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2212                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2213                 hci_emit_event(event, sizeof(event), 1);
2214             }
2215             break;
2216         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2217             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2218                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2219             }
2220             break;
2221         case HCI_EVENT_CONNECTION_REQUEST:
2222             reverse_bd_addr(&packet[2], addr);
2223             if (hci_stack->gap_classic_accept_callback != NULL){
2224                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2225                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2226                     bd_addr_copy(hci_stack->decline_addr, addr);
2227                     break;
2228                 }
2229             }
2230 
2231             // TODO: eval COD 8-10
2232             link_type = packet[11];
2233             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2234             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2235             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2236             if (!conn) {
2237                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2238             }
2239             if (!conn) {
2240                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2241                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2242                 bd_addr_copy(hci_stack->decline_addr, addr);
2243                 break;
2244             }
2245             conn->role  = HCI_ROLE_SLAVE;
2246             conn->state = RECEIVED_CONNECTION_REQUEST;
2247             // store info about eSCO
2248             if (link_type == 0x02){
2249                 conn->remote_supported_features[0] |= 1;
2250             }
2251             hci_run();
2252             break;
2253 
2254         case HCI_EVENT_CONNECTION_COMPLETE:
2255             // Connection management
2256             reverse_bd_addr(&packet[5], addr);
2257             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2258             addr_type = BD_ADDR_TYPE_ACL;
2259             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2260             if (conn) {
2261                 if (!packet[2]){
2262                     conn->state = OPEN;
2263                     conn->con_handle = little_endian_read_16(packet, 3);
2264 
2265                     // queue get remote feature
2266                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2267 
2268                     // queue set supervision timeout if we're master
2269                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2270                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2271                     }
2272 
2273                     // restart timer
2274                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2275                     btstack_run_loop_add_timer(&conn->timeout);
2276 
2277                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2278 
2279                     hci_emit_nr_connections_changed();
2280                 } else {
2281                     // connection failed
2282                     hci_handle_connection_failed(conn, packet[2]);
2283                 }
2284             }
2285             break;
2286 
2287         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2288             reverse_bd_addr(&packet[5], addr);
2289             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2290             if (packet[2]){
2291                 // connection failed
2292                 break;
2293             }
2294             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2295             if (!conn) {
2296                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2297             }
2298             if (!conn) {
2299                 break;
2300             }
2301             conn->state = OPEN;
2302             conn->con_handle = little_endian_read_16(packet, 3);
2303 
2304 #ifdef ENABLE_SCO_OVER_HCI
2305             // update SCO
2306             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2307                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2308             }
2309             // trigger can send now
2310             if (hci_have_usb_transport()){
2311                 hci_stack->sco_can_send_now = 1;
2312             }
2313 #endif
2314             break;
2315 
2316         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2317             handle = little_endian_read_16(packet, 3);
2318             conn = hci_connection_for_handle(handle);
2319             if (!conn) break;
2320             if (!packet[2]){
2321                 const uint8_t * features = &packet[5];
2322                 hci_handle_remote_features_page_0(conn, features);
2323 
2324                 // read extended features if possible
2325                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2326                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2327                     break;
2328                 }
2329             }
2330             hci_handle_remote_features_received(conn);
2331             break;
2332 
2333         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2334             handle = little_endian_read_16(packet, 3);
2335             conn = hci_connection_for_handle(handle);
2336             if (!conn) break;
2337             // status = ok, page = 1
2338             if (!packet[2]) {
2339                 uint8_t page_number = packet[5];
2340                 uint8_t maximum_page_number = packet[6];
2341                 const uint8_t * features = &packet[7];
2342                 bool done = false;
2343                 switch (page_number){
2344                     case 1:
2345                         hci_handle_remote_features_page_1(conn, features);
2346                         if (maximum_page_number >= 2){
2347                             // get Secure Connections (Controller) from Page 2 if available
2348                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2349                         } else {
2350                             // otherwise, assume SC (Controller) == SC (Host)
2351                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2352                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2353                             }
2354                             done = true;
2355                         }
2356                         break;
2357                     case 2:
2358                         hci_handle_remote_features_page_2(conn, features);
2359                         done = true;
2360                         break;
2361                     default:
2362                         break;
2363                 }
2364                 if (!done) break;
2365             }
2366             hci_handle_remote_features_received(conn);
2367             break;
2368 
2369         case HCI_EVENT_LINK_KEY_REQUEST:
2370             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2371             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2372             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2373             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2374             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2375             hci_run();
2376             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2377             return;
2378 
2379         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2380             reverse_bd_addr(&packet[2], addr);
2381             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2382             if (!conn) break;
2383             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2384             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2385             // Change Connection Encryption keeps link key type
2386             if (link_key_type != CHANGED_COMBINATION_KEY){
2387                 conn->link_key_type = link_key_type;
2388             }
2389             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2390             // still forward event to allow dismiss of pairing dialog
2391             break;
2392         }
2393 
2394         case HCI_EVENT_PIN_CODE_REQUEST:
2395             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2396             // non-bondable mode: pin code negative reply will be sent
2397             if (!hci_stack->bondable){
2398                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2399                 hci_run();
2400                 return;
2401             }
2402             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2403             if (!hci_stack->link_key_db) break;
2404             hci_event_pin_code_request_get_bd_addr(packet, addr);
2405             hci_stack->link_key_db->delete_link_key(addr);
2406             break;
2407 
2408         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2409             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2410             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2411             break;
2412 
2413         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2414             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2415             if (!hci_stack->ssp_auto_accept) break;
2416             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2417             break;
2418 
2419         case HCI_EVENT_USER_PASSKEY_REQUEST:
2420             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2421             if (!hci_stack->ssp_auto_accept) break;
2422             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2423             break;
2424         case HCI_EVENT_MODE_CHANGE:
2425             handle = hci_event_mode_change_get_handle(packet);
2426             conn = hci_connection_for_handle(handle);
2427             if (!conn) break;
2428             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2429             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2430             break;
2431 #endif
2432 
2433         case HCI_EVENT_ENCRYPTION_CHANGE:
2434             handle = hci_event_encryption_change_get_connection_handle(packet);
2435             conn = hci_connection_for_handle(handle);
2436             if (!conn) break;
2437             if (hci_event_encryption_change_get_status(packet) == 0) {
2438                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2439                 if (encryption_enabled){
2440                     if (hci_is_le_connection(conn)){
2441                         // For LE, we accept connection as encrypted
2442                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2443                     }
2444 #ifdef ENABLE_CLASSIC
2445                     else {
2446                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2447                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2448                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2449                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2450                             log_info("SC during pairing, but only E0 now -> abort");
2451                             conn->state = conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2452                             break;
2453                         }
2454 
2455                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2456                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2457                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2458                         } else {
2459                             // if not, pretend everything is perfect
2460                             conn->encryption_key_size = 16;
2461                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2462                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2463                         }
2464                     }
2465 #endif
2466                 } else {
2467                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2468                 }
2469             }
2470 
2471             break;
2472 
2473 #ifdef ENABLE_CLASSIC
2474         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2475             handle = little_endian_read_16(packet, 3);
2476             conn = hci_connection_for_handle(handle);
2477             if (!conn) break;
2478 
2479             // dedicated bonding: send result and disconnect
2480             if (conn->bonding_flags & BONDING_DEDICATED){
2481                 conn->bonding_flags &= ~BONDING_DEDICATED;
2482                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2483                 conn->bonding_status = packet[2];
2484                 break;
2485             }
2486 
2487             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2488                 // link key sufficient for requested security
2489                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2490                 break;
2491             }
2492             // not enough
2493             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2494             break;
2495 #endif
2496 
2497         // HCI_EVENT_DISCONNECTION_COMPLETE
2498         // has been split, to first notify stack before shutting connection down
2499         // see end of function, too.
2500         case HCI_EVENT_DISCONNECTION_COMPLETE:
2501             if (packet[2]) break;   // status != 0
2502             handle = little_endian_read_16(packet, 3);
2503             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2504             if (hci_stack->acl_fragmentation_total_size > 0) {
2505                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2506                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2507                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2508                     hci_stack->acl_fragmentation_total_size = 0;
2509                     hci_stack->acl_fragmentation_pos = 0;
2510                     if (release_buffer){
2511                         hci_release_packet_buffer();
2512                     }
2513                 }
2514             }
2515 
2516             conn = hci_connection_for_handle(handle);
2517             if (!conn) break;
2518             // mark connection for shutdown
2519             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2520 
2521             // emit dedicatd bonding event
2522             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2523                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2524             }
2525 
2526 #ifdef ENABLE_BLE
2527 #ifdef ENABLE_LE_PERIPHERAL
2528             // re-enable advertisements for le connections if active
2529             if (hci_is_le_connection(conn)){
2530                 hci_reenable_advertisements_if_needed();
2531             }
2532 #endif
2533 #endif
2534             break;
2535 
2536         case HCI_EVENT_HARDWARE_ERROR:
2537             log_error("Hardware Error: 0x%02x", packet[2]);
2538             if (hci_stack->hardware_error_callback){
2539                 (*hci_stack->hardware_error_callback)(packet[2]);
2540             } else {
2541                 // if no special requests, just reboot stack
2542                 hci_power_control_off();
2543                 hci_power_control_on();
2544             }
2545             break;
2546 
2547 #ifdef ENABLE_CLASSIC
2548         case HCI_EVENT_ROLE_CHANGE:
2549             if (packet[2]) break;   // status != 0
2550             reverse_bd_addr(&packet[3], addr);
2551             addr_type = BD_ADDR_TYPE_ACL;
2552             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2553             if (!conn) break;
2554             conn->role = packet[9];
2555             break;
2556 #endif
2557 
2558         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2559             // release packet buffer only for asynchronous transport and if there are not further fragements
2560             if (hci_transport_synchronous()) {
2561                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2562                 return; // instead of break: to avoid re-entering hci_run()
2563             }
2564             hci_stack->acl_fragmentation_tx_active = 0;
2565             if (hci_stack->acl_fragmentation_total_size) break;
2566             hci_release_packet_buffer();
2567 
2568             // L2CAP receives this event via the hci_emit_event below
2569 
2570 #ifdef ENABLE_CLASSIC
2571             // For SCO, we do the can_send_now_check here
2572             hci_notify_if_sco_can_send_now();
2573 #endif
2574             break;
2575 
2576 #ifdef ENABLE_CLASSIC
2577         case HCI_EVENT_SCO_CAN_SEND_NOW:
2578             // For SCO, we do the can_send_now_check here
2579             hci_stack->sco_can_send_now = 1;
2580             hci_notify_if_sco_can_send_now();
2581             return;
2582 
2583         // explode inquriy results for easier consumption
2584         case HCI_EVENT_INQUIRY_RESULT:
2585         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2586         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2587             gap_inquiry_explode(packet, size);
2588             break;
2589 #endif
2590 
2591 #ifdef ENABLE_BLE
2592         case HCI_EVENT_LE_META:
2593             switch (packet[2]){
2594 #ifdef ENABLE_LE_CENTRAL
2595                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2596                     // log_info("advertising report received");
2597                     if (!hci_stack->le_scanning_enabled) break;
2598                     le_handle_advertisement_report(packet, size);
2599                     break;
2600 #endif
2601                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2602                     // Connection management
2603                     reverse_bd_addr(&packet[8], addr);
2604                     addr_type = (bd_addr_type_t)packet[7];
2605                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2606                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2607 
2608 #ifdef ENABLE_LE_CENTRAL
2609                     // if auto-connect, remove from whitelist in both roles
2610                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2611                         hci_remove_from_whitelist(addr_type, addr);
2612                     }
2613                     // handle error: error is reported only to the initiator -> outgoing connection
2614                     if (packet[3]){
2615 
2616                         // handle cancelled outgoing connection
2617                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2618                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2619                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2620                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2621                             conn = gap_get_outgoing_connection();
2622                         }
2623 
2624                         // outgoing connection establishment is done
2625                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2626                         // remove entry
2627                         if (conn){
2628                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2629                             btstack_memory_hci_connection_free( conn );
2630                         }
2631                         break;
2632                     }
2633 #endif
2634                     // on success, both hosts receive connection complete event
2635                     if (packet[6] == HCI_ROLE_MASTER){
2636 #ifdef ENABLE_LE_CENTRAL
2637                         // if we're master, it was an outgoing connection and we're done with it
2638                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2639 #endif
2640                     } else {
2641 #ifdef ENABLE_LE_PERIPHERAL
2642                         // if we're slave, it was an incoming connection, advertisements have stopped
2643                         hci_stack->le_advertisements_active = 0;
2644 #endif
2645                     }
2646                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2647                     if (!conn){
2648                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2649                     }
2650                     // no memory, sorry.
2651                     if (!conn){
2652                         break;
2653                     }
2654 
2655                     conn->state = OPEN;
2656                     conn->role  = packet[6];
2657                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2658                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2659 
2660 #ifdef ENABLE_LE_PERIPHERAL
2661                     if (packet[6] == HCI_ROLE_SLAVE){
2662                         hci_reenable_advertisements_if_needed();
2663                     }
2664 #endif
2665 
2666                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2667 
2668                     // restart timer
2669                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2670                     // btstack_run_loop_add_timer(&conn->timeout);
2671 
2672                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2673 
2674                     hci_emit_nr_connections_changed();
2675                     break;
2676 
2677                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2678                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2679                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2680                     conn = hci_connection_for_handle(handle);
2681                     if (!conn) break;
2682                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2683                     break;
2684 
2685                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2686                     // connection
2687                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2688                     conn = hci_connection_for_handle(handle);
2689                     if (conn) {
2690                         // read arguments
2691                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2692                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2693                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2694                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2695 
2696                         // validate against current connection parameter range
2697                         le_connection_parameter_range_t existing_range;
2698                         gap_get_connection_parameter_range(&existing_range);
2699                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2700                         if (update_parameter){
2701                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2702                             conn->le_conn_interval_min = le_conn_interval_min;
2703                             conn->le_conn_interval_max = le_conn_interval_max;
2704                             conn->le_conn_latency = le_conn_latency;
2705                             conn->le_supervision_timeout = le_supervision_timeout;
2706                         } else {
2707                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2708                         }
2709                     }
2710                     break;
2711 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2712                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2713                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2714                     conn = hci_connection_for_handle(handle);
2715                     if (conn) {
2716                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2717                     }
2718                     break;
2719 #endif
2720                 default:
2721                     break;
2722             }
2723             break;
2724 #endif
2725         case HCI_EVENT_VENDOR_SPECIFIC:
2726             // Vendor specific commands often create vendor specific event instead of num completed packets
2727             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2728             switch (hci_stack->manufacturer){
2729                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2730                     hci_stack->num_cmd_packets = 1;
2731                     break;
2732                 default:
2733                     break;
2734             }
2735             break;
2736         default:
2737             break;
2738     }
2739 
2740     handle_event_for_current_stack_state(packet, size);
2741 
2742     // notify upper stack
2743 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2744 
2745     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2746     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2747         if (!packet[2]){
2748             handle = little_endian_read_16(packet, 3);
2749             hci_connection_t * aConn = hci_connection_for_handle(handle);
2750             if (aConn) {
2751                 // discard connection if app did not trigger a reconnect in the event handler
2752                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2753                     hci_shutdown_connection(aConn);
2754                 }
2755             }
2756         }
2757     }
2758 
2759 	// execute main loop
2760 	hci_run();
2761 }
2762 
2763 #ifdef ENABLE_CLASSIC
2764 
2765 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2766 static void sco_schedule_tx(hci_connection_t * conn);
2767 
2768 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2769     log_debug("SCO TX Timeout");
2770     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2771     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2772     if (!conn) return;
2773 
2774     // trigger send
2775     conn->sco_tx_ready = 1;
2776     // extra packet if CVSD but SCO buffer is too short
2777     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2778         conn->sco_tx_ready++;
2779     }
2780     hci_notify_if_sco_can_send_now();
2781 }
2782 
2783 
2784 #define SCO_TX_AFTER_RX_MS (6)
2785 
2786 static void sco_schedule_tx(hci_connection_t * conn){
2787 
2788     uint32_t now = btstack_run_loop_get_time_ms();
2789     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2790     int time_delta_ms = sco_tx_ms - now;
2791 
2792     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2793 
2794     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2795     btstack_run_loop_set_timer(timer, time_delta_ms);
2796     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2797     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2798     btstack_run_loop_add_timer(timer);
2799 }
2800 
2801 static void sco_handler(uint8_t * packet, uint16_t size){
2802     // lookup connection struct
2803     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2804     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2805     if (!conn) return;
2806 
2807     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2808     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2809         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2810             packet[2] = 0x3c;
2811             memmove(&packet[3], &packet[23], 63);
2812             size = 63;
2813         }
2814     }
2815 
2816     if (hci_have_usb_transport()){
2817         // Nothing to do
2818     } else {
2819         // 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);
2820         if (hci_stack->synchronous_flow_control_enabled == 0){
2821             uint32_t now = btstack_run_loop_get_time_ms();
2822 
2823             if (!conn->sco_rx_valid){
2824                 // ignore first 10 packets
2825                 conn->sco_rx_count++;
2826                 // log_debug("sco rx count %u", conn->sco_rx_count);
2827                 if (conn->sco_rx_count == 10) {
2828                     // use first timestamp as is and pretent it just started
2829                     conn->sco_rx_ms = now;
2830                     conn->sco_rx_valid = 1;
2831                     conn->sco_rx_count = 0;
2832                     sco_schedule_tx(conn);
2833                 }
2834             } else {
2835                 // track expected arrival timme
2836                 conn->sco_rx_count++;
2837                 conn->sco_rx_ms += 7;
2838                 int delta = (int32_t) (now - conn->sco_rx_ms);
2839                 if (delta > 0){
2840                     conn->sco_rx_ms++;
2841                 }
2842                 // log_debug("sco rx %u", conn->sco_rx_ms);
2843                 sco_schedule_tx(conn);
2844             }
2845         }
2846     }
2847     // deliver to app
2848     if (hci_stack->sco_packet_handler) {
2849         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2850     }
2851 
2852 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2853     conn->num_packets_completed++;
2854     hci_stack->host_completed_packets = 1;
2855     hci_run();
2856 #endif
2857 }
2858 #endif
2859 
2860 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2861     hci_dump_packet(packet_type, 1, packet, size);
2862     switch (packet_type) {
2863         case HCI_EVENT_PACKET:
2864             event_handler(packet, size);
2865             break;
2866         case HCI_ACL_DATA_PACKET:
2867             acl_handler(packet, size);
2868             break;
2869 #ifdef ENABLE_CLASSIC
2870         case HCI_SCO_DATA_PACKET:
2871             sco_handler(packet, size);
2872             break;
2873 #endif
2874         default:
2875             break;
2876     }
2877 }
2878 
2879 /**
2880  * @brief Add event packet handler.
2881  */
2882 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2883     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2884 }
2885 
2886 
2887 /** Register HCI packet handlers */
2888 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2889     hci_stack->acl_packet_handler = handler;
2890 }
2891 
2892 #ifdef ENABLE_CLASSIC
2893 /**
2894  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2895  */
2896 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2897     hci_stack->sco_packet_handler = handler;
2898 }
2899 #endif
2900 
2901 static void hci_state_reset(void){
2902     // no connections yet
2903     hci_stack->connections = NULL;
2904 
2905     // keep discoverable/connectable as this has been requested by the client(s)
2906     // hci_stack->discoverable = 0;
2907     // hci_stack->connectable = 0;
2908     // hci_stack->bondable = 1;
2909     // hci_stack->own_addr_type = 0;
2910 
2911     // buffer is free
2912     hci_stack->hci_packet_buffer_reserved = 0;
2913 
2914     // no pending cmds
2915     hci_stack->decline_reason = 0;
2916     hci_stack->new_scan_enable_value = 0xff;
2917 
2918     // LE
2919 #ifdef ENABLE_BLE
2920     memset(hci_stack->le_random_address, 0, 6);
2921     hci_stack->le_random_address_set = 0;
2922 #endif
2923 #ifdef ENABLE_LE_CENTRAL
2924     hci_stack->le_scanning_active  = 0;
2925     hci_stack->le_scan_type = 0xff;
2926     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2927     hci_stack->le_whitelist = 0;
2928     hci_stack->le_whitelist_capacity = 0;
2929 #endif
2930 }
2931 
2932 #ifdef ENABLE_CLASSIC
2933 /**
2934  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2935  */
2936 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2937     // store and open remote device db
2938     hci_stack->link_key_db = link_key_db;
2939     if (hci_stack->link_key_db) {
2940         hci_stack->link_key_db->open();
2941     }
2942 }
2943 #endif
2944 
2945 void hci_init(const hci_transport_t *transport, const void *config){
2946 
2947 #ifdef HAVE_MALLOC
2948     if (!hci_stack) {
2949         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2950     }
2951 #else
2952     hci_stack = &hci_stack_static;
2953 #endif
2954     memset(hci_stack, 0, sizeof(hci_stack_t));
2955 
2956     // reference to use transport layer implementation
2957     hci_stack->hci_transport = transport;
2958 
2959     // reference to used config
2960     hci_stack->config = config;
2961 
2962     // setup pointer for outgoing packet buffer
2963     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2964 
2965     // max acl payload size defined in config.h
2966     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2967 
2968     // register packet handlers with transport
2969     transport->register_packet_handler(&packet_handler);
2970 
2971     hci_stack->state = HCI_STATE_OFF;
2972 
2973     // class of device
2974     hci_stack->class_of_device = 0x007a020c; // Smartphone
2975 
2976     // bondable by default
2977     hci_stack->bondable = 1;
2978 
2979 #ifdef ENABLE_CLASSIC
2980     // classic name
2981     hci_stack->local_name = default_classic_name;
2982 
2983     // Master slave policy
2984     hci_stack->master_slave_policy = 1;
2985 
2986     // Allow Role Switch
2987     hci_stack->allow_role_switch = 1;
2988 
2989     // Default / minimum security level = 2
2990     hci_stack->gap_security_level = LEVEL_2;
2991 
2992     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2993     hci_stack->gap_required_encyrption_key_size = 16;
2994 #endif
2995 
2996     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2997     hci_stack->ssp_enable = 1;
2998     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2999     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3000     hci_stack->ssp_auto_accept = 1;
3001 
3002     // Secure Connections: enable (requires support from Controller)
3003     hci_stack->secure_connections_enable = true;
3004 
3005     // voice setting - signed 16 bit pcm data with CVSD over the air
3006     hci_stack->sco_voice_setting = 0x60;
3007 
3008 #ifdef ENABLE_LE_CENTRAL
3009     // connection parameter to use for outgoing connections
3010     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3011     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3012     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3013     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3014     hci_stack->le_connection_latency      = 4;         // 4
3015     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3016     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3017     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3018 
3019     // default LE Scanning
3020     hci_stack->le_scan_interval = 0x1e0;
3021     hci_stack->le_scan_window   =  0x30;
3022 #endif
3023 
3024 #ifdef ENABLE_LE_PERIPHERAL
3025     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3026 #endif
3027 
3028     // connection parameter range used to answer connection parameter update requests in l2cap
3029     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3030     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3031     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3032     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3033     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3034     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3035 
3036     hci_state_reset();
3037 }
3038 
3039 /**
3040  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3041  */
3042 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3043     hci_stack->chipset = chipset_driver;
3044 
3045     // reset chipset driver - init is also called on power_up
3046     if (hci_stack->chipset && hci_stack->chipset->init){
3047         hci_stack->chipset->init(hci_stack->config);
3048     }
3049 }
3050 
3051 /**
3052  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3053  */
3054 void hci_set_control(const btstack_control_t *hardware_control){
3055     // references to used control implementation
3056     hci_stack->control = hardware_control;
3057     // init with transport config
3058     hardware_control->init(hci_stack->config);
3059 }
3060 
3061 void hci_close(void){
3062     // close remote device db
3063     if (hci_stack->link_key_db) {
3064         hci_stack->link_key_db->close();
3065     }
3066 
3067     btstack_linked_list_iterator_t lit;
3068     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3069     while (btstack_linked_list_iterator_has_next(&lit)){
3070         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3071         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3072         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3073         hci_shutdown_connection(connection);
3074     }
3075 
3076     hci_power_control(HCI_POWER_OFF);
3077 
3078 #ifdef HAVE_MALLOC
3079     free(hci_stack);
3080 #endif
3081     hci_stack = NULL;
3082 }
3083 
3084 #ifdef ENABLE_CLASSIC
3085 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3086     // validate ranage and set
3087     if (encryption_key_size < 7)  return;
3088     if (encryption_key_size > 16) return;
3089     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3090 }
3091 
3092 void gap_set_security_level(gap_security_level_t security_level){
3093     hci_stack->gap_security_level = security_level;
3094 }
3095 
3096 gap_security_level_t gap_get_security_level(void){
3097     return hci_stack->gap_security_level;
3098 }
3099 #endif
3100 
3101 #ifdef ENABLE_CLASSIC
3102 void gap_set_class_of_device(uint32_t class_of_device){
3103     hci_stack->class_of_device = class_of_device;
3104 }
3105 
3106 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3107     hci_stack->default_link_policy_settings = default_link_policy_settings;
3108 }
3109 
3110 void gap_set_allow_role_switch(bool allow_role_switch){
3111     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3112 }
3113 
3114 uint8_t hci_get_allow_role_switch(void){
3115     return  hci_stack->allow_role_switch;
3116 }
3117 
3118 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3119     hci_stack->link_supervision_timeout = link_supervision_timeout;
3120 }
3121 
3122 void hci_disable_l2cap_timeout_check(void){
3123     disable_l2cap_timeouts = 1;
3124 }
3125 #endif
3126 
3127 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3128 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3129 void hci_set_bd_addr(bd_addr_t addr){
3130     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3131     hci_stack->custom_bd_addr_set = 1;
3132 }
3133 #endif
3134 
3135 // State-Module-Driver overview
3136 // state                    module  low-level
3137 // HCI_STATE_OFF             off      close
3138 // HCI_STATE_INITIALIZING,   on       open
3139 // HCI_STATE_WORKING,        on       open
3140 // HCI_STATE_HALTING,        on       open
3141 // HCI_STATE_SLEEPING,    off/sleep   close
3142 // HCI_STATE_FALLING_ASLEEP  on       open
3143 
3144 static int hci_power_control_on(void){
3145 
3146     // power on
3147     int err = 0;
3148     if (hci_stack->control && hci_stack->control->on){
3149         err = (*hci_stack->control->on)();
3150     }
3151     if (err){
3152         log_error( "POWER_ON failed");
3153         hci_emit_hci_open_failed();
3154         return err;
3155     }
3156 
3157     // int chipset driver
3158     if (hci_stack->chipset && hci_stack->chipset->init){
3159         hci_stack->chipset->init(hci_stack->config);
3160     }
3161 
3162     // init transport
3163     if (hci_stack->hci_transport->init){
3164         hci_stack->hci_transport->init(hci_stack->config);
3165     }
3166 
3167     // open transport
3168     err = hci_stack->hci_transport->open();
3169     if (err){
3170         log_error( "HCI_INIT failed, turning Bluetooth off again");
3171         if (hci_stack->control && hci_stack->control->off){
3172             (*hci_stack->control->off)();
3173         }
3174         hci_emit_hci_open_failed();
3175         return err;
3176     }
3177     return 0;
3178 }
3179 
3180 static void hci_power_control_off(void){
3181 
3182     log_info("hci_power_control_off");
3183 
3184     // close low-level device
3185     hci_stack->hci_transport->close();
3186 
3187     log_info("hci_power_control_off - hci_transport closed");
3188 
3189     // power off
3190     if (hci_stack->control && hci_stack->control->off){
3191         (*hci_stack->control->off)();
3192     }
3193 
3194     log_info("hci_power_control_off - control closed");
3195 
3196     hci_stack->state = HCI_STATE_OFF;
3197 }
3198 
3199 static void hci_power_control_sleep(void){
3200 
3201     log_info("hci_power_control_sleep");
3202 
3203 #if 0
3204     // don't close serial port during sleep
3205 
3206     // close low-level device
3207     hci_stack->hci_transport->close(hci_stack->config);
3208 #endif
3209 
3210     // sleep mode
3211     if (hci_stack->control && hci_stack->control->sleep){
3212         (*hci_stack->control->sleep)();
3213     }
3214 
3215     hci_stack->state = HCI_STATE_SLEEPING;
3216 }
3217 
3218 static int hci_power_control_wake(void){
3219 
3220     log_info("hci_power_control_wake");
3221 
3222     // wake on
3223     if (hci_stack->control && hci_stack->control->wake){
3224         (*hci_stack->control->wake)();
3225     }
3226 
3227 #if 0
3228     // open low-level device
3229     int err = hci_stack->hci_transport->open(hci_stack->config);
3230     if (err){
3231         log_error( "HCI_INIT failed, turning Bluetooth off again");
3232         if (hci_stack->control && hci_stack->control->off){
3233             (*hci_stack->control->off)();
3234         }
3235         hci_emit_hci_open_failed();
3236         return err;
3237     }
3238 #endif
3239 
3240     return 0;
3241 }
3242 
3243 static void hci_power_transition_to_initializing(void){
3244     // set up state machine
3245     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3246     hci_stack->hci_packet_buffer_reserved = 0;
3247     hci_stack->state = HCI_STATE_INITIALIZING;
3248     hci_stack->substate = HCI_INIT_SEND_RESET;
3249 }
3250 
3251 int hci_power_control(HCI_POWER_MODE power_mode){
3252 
3253     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3254 
3255     int err = 0;
3256     switch (hci_stack->state){
3257 
3258         case HCI_STATE_OFF:
3259             switch (power_mode){
3260                 case HCI_POWER_ON:
3261                     err = hci_power_control_on();
3262                     if (err) {
3263                         log_error("hci_power_control_on() error %d", err);
3264                         return err;
3265                     }
3266                     hci_power_transition_to_initializing();
3267                     break;
3268                 case HCI_POWER_OFF:
3269                     // do nothing
3270                     break;
3271                 case HCI_POWER_SLEEP:
3272                     // do nothing (with SLEEP == OFF)
3273                     break;
3274             }
3275             break;
3276 
3277         case HCI_STATE_INITIALIZING:
3278             switch (power_mode){
3279                 case HCI_POWER_ON:
3280                     // do nothing
3281                     break;
3282                 case HCI_POWER_OFF:
3283                     // no connections yet, just turn it off
3284                     hci_power_control_off();
3285                     break;
3286                 case HCI_POWER_SLEEP:
3287                     // no connections yet, just turn it off
3288                     hci_power_control_sleep();
3289                     break;
3290             }
3291             break;
3292 
3293         case HCI_STATE_WORKING:
3294             switch (power_mode){
3295                 case HCI_POWER_ON:
3296                     // do nothing
3297                     break;
3298                 case HCI_POWER_OFF:
3299                     // see hci_run
3300                     hci_stack->state = HCI_STATE_HALTING;
3301                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3302                     break;
3303                 case HCI_POWER_SLEEP:
3304                     // see hci_run
3305                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3306                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3307                     break;
3308             }
3309             break;
3310 
3311         case HCI_STATE_HALTING:
3312             switch (power_mode){
3313                 case HCI_POWER_ON:
3314                     hci_power_transition_to_initializing();
3315                     break;
3316                 case HCI_POWER_OFF:
3317                     // do nothing
3318                     break;
3319                 case HCI_POWER_SLEEP:
3320                     // see hci_run
3321                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3322                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3323                     break;
3324             }
3325             break;
3326 
3327         case HCI_STATE_FALLING_ASLEEP:
3328             switch (power_mode){
3329                 case HCI_POWER_ON:
3330 
3331 #ifdef HAVE_PLATFORM_IPHONE_OS
3332                     // nothing to do, if H4 supports power management
3333                     if (btstack_control_iphone_power_management_enabled()){
3334                         hci_stack->state = HCI_STATE_INITIALIZING;
3335                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3336                         break;
3337                     }
3338 #endif
3339                     hci_power_transition_to_initializing();
3340                     break;
3341                 case HCI_POWER_OFF:
3342                     // see hci_run
3343                     hci_stack->state = HCI_STATE_HALTING;
3344                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3345                     break;
3346                 case HCI_POWER_SLEEP:
3347                     // do nothing
3348                     break;
3349             }
3350             break;
3351 
3352         case HCI_STATE_SLEEPING:
3353             switch (power_mode){
3354                 case HCI_POWER_ON:
3355 
3356 #ifdef HAVE_PLATFORM_IPHONE_OS
3357                     // nothing to do, if H4 supports power management
3358                     if (btstack_control_iphone_power_management_enabled()){
3359                         hci_stack->state = HCI_STATE_INITIALIZING;
3360                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3361                         hci_update_scan_enable();
3362                         break;
3363                     }
3364 #endif
3365                     err = hci_power_control_wake();
3366                     if (err) return err;
3367                     hci_power_transition_to_initializing();
3368                     break;
3369                 case HCI_POWER_OFF:
3370                     hci_stack->state = HCI_STATE_HALTING;
3371                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3372                     break;
3373                 case HCI_POWER_SLEEP:
3374                     // do nothing
3375                     break;
3376             }
3377             break;
3378     }
3379 
3380     // create internal event
3381 	hci_emit_state();
3382 
3383 	// trigger next/first action
3384 	hci_run();
3385 
3386     return 0;
3387 }
3388 
3389 
3390 #ifdef ENABLE_CLASSIC
3391 
3392 static void hci_update_scan_enable(void){
3393     // 2 = page scan, 1 = inq scan
3394     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3395     hci_run();
3396 }
3397 
3398 void gap_discoverable_control(uint8_t enable){
3399     if (enable) enable = 1; // normalize argument
3400 
3401     if (hci_stack->discoverable == enable){
3402         hci_emit_discoverable_enabled(hci_stack->discoverable);
3403         return;
3404     }
3405 
3406     hci_stack->discoverable = enable;
3407     hci_update_scan_enable();
3408 }
3409 
3410 void gap_connectable_control(uint8_t enable){
3411     if (enable) enable = 1; // normalize argument
3412 
3413     // don't emit event
3414     if (hci_stack->connectable == enable) return;
3415 
3416     hci_stack->connectable = enable;
3417     hci_update_scan_enable();
3418 }
3419 #endif
3420 
3421 void gap_local_bd_addr(bd_addr_t address_buffer){
3422     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3423 }
3424 
3425 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3426 static void hci_host_num_completed_packets(void){
3427 
3428     // create packet manually as arrays are not supported and num_commands should not get reduced
3429     hci_reserve_packet_buffer();
3430     uint8_t * packet = hci_get_outgoing_packet_buffer();
3431 
3432     uint16_t size = 0;
3433     uint16_t num_handles = 0;
3434     packet[size++] = 0x35;
3435     packet[size++] = 0x0c;
3436     size++;  // skip param len
3437     size++;  // skip num handles
3438 
3439     // add { handle, packets } entries
3440     btstack_linked_item_t * it;
3441     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3442         hci_connection_t * connection = (hci_connection_t *) it;
3443         if (connection->num_packets_completed){
3444             little_endian_store_16(packet, size, connection->con_handle);
3445             size += 2;
3446             little_endian_store_16(packet, size, connection->num_packets_completed);
3447             size += 2;
3448             //
3449             num_handles++;
3450             connection->num_packets_completed = 0;
3451         }
3452     }
3453 
3454     packet[2] = size - 3;
3455     packet[3] = num_handles;
3456 
3457     hci_stack->host_completed_packets = 0;
3458 
3459     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3460     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3461 
3462     // release packet buffer for synchronous transport implementations
3463     if (hci_transport_synchronous()){
3464         hci_release_packet_buffer();
3465         hci_emit_transport_packet_sent();
3466     }
3467 }
3468 #endif
3469 
3470 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3471     UNUSED(ds);
3472     hci_stack->substate = HCI_HALTING_CLOSE;
3473     // allow packet handlers to defer final shutdown
3474     hci_emit_state();
3475     hci_run();
3476 }
3477 
3478 static bool hci_run_acl_fragments(void){
3479     if (hci_stack->acl_fragmentation_total_size > 0) {
3480         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3481         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3482         if (connection) {
3483             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3484                 hci_send_acl_packet_fragments(connection);
3485                 return true;
3486             }
3487         } else {
3488             // connection gone -> discard further fragments
3489             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3490             hci_stack->acl_fragmentation_total_size = 0;
3491             hci_stack->acl_fragmentation_pos = 0;
3492         }
3493     }
3494     return false;
3495 }
3496 
3497 #ifdef ENABLE_CLASSIC
3498 static bool hci_run_general_gap_classic(void){
3499 
3500     // decline incoming connections
3501     if (hci_stack->decline_reason){
3502         uint8_t reason = hci_stack->decline_reason;
3503         hci_stack->decline_reason = 0;
3504         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3505         return true;
3506     }
3507     // send scan enable
3508     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3509         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3510         hci_stack->new_scan_enable_value = 0xff;
3511         return true;
3512     }
3513     // start/stop inquiry
3514     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3515         uint8_t duration = hci_stack->inquiry_state;
3516         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3517         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3518         return true;
3519     }
3520     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3521         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3522         hci_send_cmd(&hci_inquiry_cancel);
3523         return true;
3524     }
3525     // remote name request
3526     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3527         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3528         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3529                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3530         return true;
3531     }
3532     // pairing
3533     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3534         uint8_t state = hci_stack->gap_pairing_state;
3535         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3536         switch (state){
3537             case GAP_PAIRING_STATE_SEND_PIN:
3538                 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);
3539                 break;
3540             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3541                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3542                 break;
3543             case GAP_PAIRING_STATE_SEND_PASSKEY:
3544                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3545                 break;
3546             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3547                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3548                 break;
3549             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3550                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3551                 break;
3552             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3553                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3554                 break;
3555             default:
3556                 break;
3557         }
3558         return true;
3559     }
3560     return false;
3561 }
3562 #endif
3563 
3564 #ifdef ENABLE_BLE
3565 static bool hci_run_general_gap_le(void){
3566 
3567     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3568 
3569     if (hci_stack->state != HCI_STATE_WORKING) return false;
3570     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3571 
3572 #ifdef ENABLE_LE_CENTRAL
3573     // parameter change requires scanning to be stopped first
3574     if (hci_stack->le_scan_type != 0xff) {
3575         if (hci_stack->le_scanning_active){
3576             hci_stack->le_scanning_active = 0;
3577             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3578         } else {
3579             int scan_type = (int) hci_stack->le_scan_type;
3580             hci_stack->le_scan_type = 0xff;
3581             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);
3582         }
3583         return true;
3584     }
3585     // finally, we can enable/disable le scan
3586     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3587         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3588         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3589         return true;
3590     }
3591 #endif
3592 #ifdef ENABLE_LE_PERIPHERAL
3593     // le advertisement control
3594     if (hci_stack->le_advertisements_todo){
3595         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3596     }
3597     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3598         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3599         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3600         return true;
3601     }
3602     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3603         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3604         hci_send_cmd(&hci_le_set_advertising_parameters,
3605                      hci_stack->le_advertisements_interval_min,
3606                      hci_stack->le_advertisements_interval_max,
3607                      hci_stack->le_advertisements_type,
3608                      hci_stack->le_own_addr_type,
3609                      hci_stack->le_advertisements_direct_address_type,
3610                      hci_stack->le_advertisements_direct_address,
3611                      hci_stack->le_advertisements_channel_map,
3612                      hci_stack->le_advertisements_filter_policy);
3613         return true;
3614     }
3615     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3616         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3617         uint8_t adv_data_clean[31];
3618         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3619         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3620                      hci_stack->le_advertisements_data_len);
3621         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3622         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3623         return true;
3624     }
3625     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3626         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3627         uint8_t scan_data_clean[31];
3628         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3629         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3630                      hci_stack->le_scan_response_data_len);
3631         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3632         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3633         return true;
3634     }
3635     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3636         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3637         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3638         return true;
3639     }
3640 #endif
3641 
3642 #ifdef ENABLE_LE_CENTRAL
3643     //
3644     // LE Whitelist Management
3645     //
3646 
3647     // check if whitelist needs modification
3648     btstack_linked_list_iterator_t lit;
3649     int modification_pending = 0;
3650     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3651     while (btstack_linked_list_iterator_has_next(&lit)){
3652         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3653         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3654             modification_pending = 1;
3655             break;
3656         }
3657     }
3658 
3659     if (modification_pending){
3660         // stop connnecting if modification pending
3661         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3662             hci_send_cmd(&hci_le_create_connection_cancel);
3663             return true;
3664         }
3665 
3666         // add/remove entries
3667         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3668         while (btstack_linked_list_iterator_has_next(&lit)){
3669             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3670             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3671                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3672                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3673                 return true;
3674             }
3675             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3676                 bd_addr_t address;
3677                 bd_addr_type_t address_type = entry->address_type;
3678                 (void)memcpy(address, entry->address, 6);
3679                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3680                 btstack_memory_whitelist_entry_free(entry);
3681                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3682                 return true;
3683             }
3684         }
3685     }
3686 
3687     // start connecting
3688     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3689          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3690         bd_addr_t null_addr;
3691         memset(null_addr, 0, 6);
3692         hci_send_cmd(&hci_le_create_connection,
3693                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3694                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3695                      1,         // use whitelist
3696                      0,         // peer address type
3697                      null_addr, // peer bd addr
3698                      hci_stack->le_own_addr_type, // our addr type:
3699                      hci_stack->le_connection_interval_min,    // conn interval min
3700                      hci_stack->le_connection_interval_max,    // conn interval max
3701                      hci_stack->le_connection_latency,         // conn latency
3702                      hci_stack->le_supervision_timeout,        // conn latency
3703                      hci_stack->le_minimum_ce_length,          // min ce length
3704                      hci_stack->le_maximum_ce_length           // max ce length
3705         );
3706         return true;
3707     }
3708 #endif
3709     return false;
3710 }
3711 #endif
3712 
3713 static bool hci_run_general_pending_commmands(void){
3714     btstack_linked_item_t * it;
3715     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3716         hci_connection_t * connection = (hci_connection_t *) it;
3717 
3718         switch(connection->state){
3719             case SEND_CREATE_CONNECTION:
3720                 switch(connection->address_type){
3721 #ifdef ENABLE_CLASSIC
3722                     case BD_ADDR_TYPE_ACL:
3723                         log_info("sending hci_create_connection");
3724                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3725                         break;
3726 #endif
3727                     default:
3728 #ifdef ENABLE_BLE
3729 #ifdef ENABLE_LE_CENTRAL
3730                         // track outgoing connection
3731                         hci_stack->outgoing_addr_type = connection->address_type;
3732                         (void)memcpy(hci_stack->outgoing_addr,
3733                                      connection->address, 6);
3734                         log_info("sending hci_le_create_connection");
3735                         hci_send_cmd(&hci_le_create_connection,
3736                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3737                                      hci_stack->le_connection_scan_window,      // conn scan windows
3738                                      0,         // don't use whitelist
3739                                      connection->address_type, // peer address type
3740                                      connection->address,      // peer bd addr
3741                                      hci_stack->le_own_addr_type, // our addr type:
3742                                      hci_stack->le_connection_interval_min,    // conn interval min
3743                                      hci_stack->le_connection_interval_max,    // conn interval max
3744                                      hci_stack->le_connection_latency,         // conn latency
3745                                      hci_stack->le_supervision_timeout,        // conn latency
3746                                      hci_stack->le_minimum_ce_length,          // min ce length
3747                                      hci_stack->le_maximum_ce_length          // max ce length
3748                         );
3749                         connection->state = SENT_CREATE_CONNECTION;
3750 #endif
3751 #endif
3752                         break;
3753                 }
3754                 return true;
3755 
3756 #ifdef ENABLE_CLASSIC
3757             case RECEIVED_CONNECTION_REQUEST:
3758                 connection->role  = HCI_ROLE_SLAVE;
3759                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3760                     log_info("sending hci_accept_connection_request");
3761                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3762                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3763                 }
3764                 return true;
3765 #endif
3766 
3767 #ifdef ENABLE_BLE
3768 #ifdef ENABLE_LE_CENTRAL
3769             case SEND_CANCEL_CONNECTION:
3770                 connection->state = SENT_CANCEL_CONNECTION;
3771                 hci_send_cmd(&hci_le_create_connection_cancel);
3772                 return true;
3773 #endif
3774 #endif
3775             case SEND_DISCONNECT:
3776                 connection->state = SENT_DISCONNECT;
3777                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3778                 return true;
3779 
3780             default:
3781                 break;
3782         }
3783 
3784         // no further commands if connection is about to get shut down
3785         if (connection->state == SENT_DISCONNECT) continue;
3786 
3787         if (connection->authentication_flags & READ_RSSI){
3788             connectionClearAuthenticationFlags(connection, READ_RSSI);
3789             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3790             return true;
3791         }
3792 
3793 #ifdef ENABLE_CLASSIC
3794 
3795         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3796             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3797             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3798             return true;
3799         }
3800 
3801         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3802             log_info("responding to link key request");
3803             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3804 
3805             link_key_t link_key;
3806             link_key_type_t link_key_type;
3807             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
3808 
3809             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
3810             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
3811             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
3812             if (sc_downgrade){
3813                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
3814                 connection->state = SENT_DISCONNECT;
3815                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3816                 return true;
3817             }
3818 
3819             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
3820             if (have_link_key && security_level_sufficient){
3821                 connection->link_key_type = link_key_type;
3822                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3823             } else {
3824                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3825             }
3826             return true;
3827         }
3828 
3829         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3830             log_info("denying to pin request");
3831             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3832             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3833             return true;
3834         }
3835 
3836         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3837             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3838             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3839             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3840                 // tweak authentication requirements
3841                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3842                 if (connection->bonding_flags & BONDING_DEDICATED){
3843                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3844                 }
3845                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3846                     authreq |= 1;
3847                 }
3848                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3849             } else {
3850                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3851             }
3852             return true;
3853         }
3854 
3855         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3856             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3857             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3858             return true;
3859         }
3860 
3861         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3862             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3863             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3864             return true;
3865         }
3866 
3867         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3868             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3869             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3870             return true;
3871         }
3872 
3873         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3874             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3875             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3876             return true;
3877         }
3878 
3879         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
3880             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
3881             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
3882             return true;
3883         }
3884 
3885         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3886             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3887             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3888             connection->state = SENT_DISCONNECT;
3889             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3890             return true;
3891         }
3892 
3893         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3894             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3895             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3896             return true;
3897         }
3898 
3899         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3900             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3901             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3902             return true;
3903         }
3904         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3905             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3906             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3907             return true;
3908         }
3909 #endif
3910 
3911         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3912             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3913             if (connection->state != SENT_DISCONNECT){
3914                 connection->state = SENT_DISCONNECT;
3915                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3916                 return true;
3917             }
3918         }
3919 
3920 #ifdef ENABLE_CLASSIC
3921         uint16_t sniff_min_interval;
3922         switch (connection->sniff_min_interval){
3923             case 0:
3924                 break;
3925             case 0xffff:
3926                 connection->sniff_min_interval = 0;
3927                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3928                 return true;
3929             default:
3930                 sniff_min_interval = connection->sniff_min_interval;
3931                 connection->sniff_min_interval = 0;
3932                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3933                 return true;
3934         }
3935 #endif
3936 
3937 #ifdef ENABLE_BLE
3938         switch (connection->le_con_parameter_update_state){
3939             // response to L2CAP CON PARAMETER UPDATE REQUEST
3940             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3941                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3942                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3943                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3944                              0x0000, 0xffff);
3945                 return true;
3946             case CON_PARAMETER_UPDATE_REPLY:
3947                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3948                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3949                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3950                              0x0000, 0xffff);
3951                 return true;
3952             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3953                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3954                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3955                 return true;
3956             default:
3957                 break;
3958         }
3959         if (connection->le_phy_update_all_phys != 0xff){
3960             uint8_t all_phys = connection->le_phy_update_all_phys;
3961             connection->le_phy_update_all_phys = 0xff;
3962             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);
3963             return true;
3964         }
3965 #endif
3966     }
3967     return false;
3968 }
3969 
3970 static void hci_run(void){
3971 
3972     bool done;
3973 
3974     // send continuation fragments first, as they block the prepared packet buffer
3975     done = hci_run_acl_fragments();
3976     if (done) return;
3977 
3978 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3979     // send host num completed packets next as they don't require num_cmd_packets > 0
3980     if (!hci_can_send_comand_packet_transport()) return;
3981     if (hci_stack->host_completed_packets){
3982         hci_host_num_completed_packets();
3983         return;
3984     }
3985 #endif
3986 
3987     if (!hci_can_send_command_packet_now()) return;
3988 
3989     // global/non-connection oriented commands
3990 
3991 
3992 #ifdef ENABLE_CLASSIC
3993     // general gap classic
3994     done = hci_run_general_gap_classic();
3995     if (done) return;
3996 #endif
3997 
3998 #ifdef ENABLE_BLE
3999     // general gap le
4000     done = hci_run_general_gap_le();
4001     if (done) return;
4002 #endif
4003 
4004     // send pending HCI commands
4005     done = hci_run_general_pending_commmands();
4006     if (done) return;
4007 
4008     // stack state sub statemachines
4009     hci_connection_t * connection;
4010     switch (hci_stack->state){
4011         case HCI_STATE_INITIALIZING:
4012             hci_initializing_run();
4013             break;
4014 
4015         case HCI_STATE_HALTING:
4016 
4017             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4018             switch (hci_stack->substate){
4019                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4020                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4021 
4022 #ifdef ENABLE_BLE
4023 #ifdef ENABLE_LE_CENTRAL
4024                     // free whitelist entries
4025                     {
4026                         btstack_linked_list_iterator_t lit;
4027                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4028                         while (btstack_linked_list_iterator_has_next(&lit)){
4029                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4030                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4031                             btstack_memory_whitelist_entry_free(entry);
4032                         }
4033                     }
4034 #endif
4035 #endif
4036                     // close all open connections
4037                     connection =  (hci_connection_t *) hci_stack->connections;
4038                     if (connection){
4039                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4040                         if (!hci_can_send_command_packet_now()) return;
4041 
4042                         // check state
4043                         if (connection->state == SENT_DISCONNECT) return;
4044                         connection->state = SENT_DISCONNECT;
4045 
4046                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4047 
4048                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4049                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4050 
4051                         // ... which would be ignored anyway as we shutdown (free) the connection now
4052                         hci_shutdown_connection(connection);
4053 
4054                         // finally, send the disconnect command
4055                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4056                         return;
4057                     }
4058 
4059                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4060                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4061                         log_info("HCI_STATE_HALTING: wait 50 ms");
4062                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4063                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4064                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4065                         btstack_run_loop_add_timer(&hci_stack->timeout);
4066                         break;
4067                     }
4068 
4069                     /* fall through */
4070 
4071                 case HCI_HALTING_CLOSE:
4072                     log_info("HCI_STATE_HALTING, calling off");
4073 
4074                     // switch mode
4075                     hci_power_control_off();
4076 
4077                     log_info("HCI_STATE_HALTING, emitting state");
4078                     hci_emit_state();
4079                     log_info("HCI_STATE_HALTING, done");
4080                     break;
4081 
4082                 case HCI_HALTING_W4_TIMER:
4083                     // keep waiting
4084 
4085                     break;
4086                 default:
4087                     break;
4088             }
4089 
4090             break;
4091 
4092         case HCI_STATE_FALLING_ASLEEP:
4093             switch(hci_stack->substate) {
4094                 case HCI_FALLING_ASLEEP_DISCONNECT:
4095                     log_info("HCI_STATE_FALLING_ASLEEP");
4096                     // close all open connections
4097                     connection =  (hci_connection_t *) hci_stack->connections;
4098 
4099 #ifdef HAVE_PLATFORM_IPHONE_OS
4100                     // don't close connections, if H4 supports power management
4101                     if (btstack_control_iphone_power_management_enabled()){
4102                         connection = NULL;
4103                     }
4104 #endif
4105                     if (connection){
4106 
4107                         // send disconnect
4108                         if (!hci_can_send_command_packet_now()) return;
4109 
4110                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4111                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4112 
4113                         // send disconnected event right away - causes higher layer connections to get closed, too.
4114                         hci_shutdown_connection(connection);
4115                         return;
4116                     }
4117 
4118                     if (hci_classic_supported()){
4119                         // disable page and inquiry scan
4120                         if (!hci_can_send_command_packet_now()) return;
4121 
4122                         log_info("HCI_STATE_HALTING, disabling inq scans");
4123                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4124 
4125                         // continue in next sub state
4126                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4127                         break;
4128                     }
4129 
4130                     /* fall through */
4131 
4132                 case HCI_FALLING_ASLEEP_COMPLETE:
4133                     log_info("HCI_STATE_HALTING, calling sleep");
4134 #ifdef HAVE_PLATFORM_IPHONE_OS
4135                     // don't actually go to sleep, if H4 supports power management
4136                     if (btstack_control_iphone_power_management_enabled()){
4137                         // SLEEP MODE reached
4138                         hci_stack->state = HCI_STATE_SLEEPING;
4139                         hci_emit_state();
4140                         break;
4141                     }
4142 #endif
4143                     // switch mode
4144                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4145                     hci_emit_state();
4146                     break;
4147 
4148                 default:
4149                     break;
4150             }
4151             break;
4152 
4153         default:
4154             break;
4155     }
4156 }
4157 
4158 int hci_send_cmd_packet(uint8_t *packet, int size){
4159     // house-keeping
4160 
4161     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4162         hci_stack->loopback_mode = packet[3];
4163     }
4164 
4165 #ifdef ENABLE_CLASSIC
4166     bd_addr_t addr;
4167     hci_connection_t * conn;
4168 
4169     // create_connection?
4170     if (IS_COMMAND(packet, hci_create_connection)){
4171         reverse_bd_addr(&packet[3], addr);
4172         log_info("Create_connection to %s", bd_addr_to_str(addr));
4173 
4174         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4175         if (!conn){
4176             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4177             if (!conn){
4178                 // notify client that alloc failed
4179                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4180                 return -1; // packet not sent to controller
4181             }
4182             conn->state = SEND_CREATE_CONNECTION;
4183         }
4184         log_info("conn state %u", conn->state);
4185         switch (conn->state){
4186             // if connection active exists
4187             case OPEN:
4188                 // and OPEN, emit connection complete command
4189                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4190                 return -1; // packet not sent to controller
4191             case RECEIVED_DISCONNECTION_COMPLETE:
4192                 // create connection triggered in disconnect complete event, let's do it now
4193                 break;
4194             case SEND_CREATE_CONNECTION:
4195                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4196                 break;
4197             default:
4198                 // otherwise, just ignore as it is already in the open process
4199                 return -1; // packet not sent to controller
4200         }
4201         conn->state = SENT_CREATE_CONNECTION;
4202 
4203         // track outgoing connection
4204         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4205         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4206     }
4207 
4208     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4209         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4210     }
4211     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4212         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4213     }
4214 
4215     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4216         if (hci_stack->link_key_db){
4217             reverse_bd_addr(&packet[3], addr);
4218             hci_stack->link_key_db->delete_link_key(addr);
4219         }
4220     }
4221 
4222     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4223     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4224         reverse_bd_addr(&packet[3], addr);
4225         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4226         if (conn){
4227             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4228         }
4229     }
4230 
4231     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4232     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4233     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4234     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4235         reverse_bd_addr(&packet[3], addr);
4236         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4237         if (conn){
4238             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4239         }
4240     }
4241 
4242 #ifdef ENABLE_SCO_OVER_HCI
4243     // setup_synchronous_connection? Voice setting at offset 22
4244     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4245         // TODO: compare to current setting if sco connection already active
4246         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4247     }
4248     // accept_synchronus_connection? Voice setting at offset 18
4249     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4250         // TODO: compare to current setting if sco connection already active
4251         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4252     }
4253 #endif
4254 #endif
4255 
4256 #ifdef ENABLE_BLE
4257     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4258         hci_stack->le_random_address_set = 1;
4259         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4260     }
4261 #ifdef ENABLE_LE_PERIPHERAL
4262     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4263         hci_stack->le_advertisements_active = packet[3];
4264     }
4265 #endif
4266 #ifdef ENABLE_LE_CENTRAL
4267     else if (IS_COMMAND(packet, hci_le_create_connection)){
4268         // white list used?
4269         uint8_t initiator_filter_policy = packet[7];
4270         switch (initiator_filter_policy){
4271             case 0:
4272                 // whitelist not used
4273                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4274                 break;
4275             case 1:
4276                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4277                 break;
4278             default:
4279                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4280                 break;
4281         }
4282     }
4283     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4284         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4285     }
4286 #endif
4287 #endif
4288 
4289     hci_stack->num_cmd_packets--;
4290 
4291     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4292     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4293 }
4294 
4295 // disconnect because of security block
4296 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4297     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4298     if (!connection) return;
4299     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4300 }
4301 
4302 
4303 // Configure Secure Simple Pairing
4304 
4305 #ifdef ENABLE_CLASSIC
4306 
4307 // enable will enable SSP during init
4308 void gap_ssp_set_enable(int enable){
4309     hci_stack->ssp_enable = enable;
4310 }
4311 
4312 static int hci_local_ssp_activated(void){
4313     return gap_ssp_supported() && hci_stack->ssp_enable;
4314 }
4315 
4316 // if set, BTstack will respond to io capability request using authentication requirement
4317 void gap_ssp_set_io_capability(int io_capability){
4318     hci_stack->ssp_io_capability = io_capability;
4319 }
4320 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4321     hci_stack->ssp_authentication_requirement = authentication_requirement;
4322 }
4323 
4324 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4325 void gap_ssp_set_auto_accept(int auto_accept){
4326     hci_stack->ssp_auto_accept = auto_accept;
4327 }
4328 
4329 void gap_secure_connections_enable(bool enable){
4330     hci_stack->secure_connections_enable = enable;
4331 }
4332 
4333 #endif
4334 
4335 // va_list part of hci_send_cmd
4336 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4337     if (!hci_can_send_command_packet_now()){
4338         log_error("hci_send_cmd called but cannot send packet now");
4339         return 0;
4340     }
4341 
4342     // for HCI INITIALIZATION
4343     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4344     hci_stack->last_cmd_opcode = cmd->opcode;
4345 
4346     hci_reserve_packet_buffer();
4347     uint8_t * packet = hci_stack->hci_packet_buffer;
4348     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4349     int err = hci_send_cmd_packet(packet, size);
4350 
4351     // release packet buffer on error or for synchronous transport implementations
4352     if ((err < 0) || hci_transport_synchronous()){
4353         hci_release_packet_buffer();
4354         hci_emit_transport_packet_sent();
4355     }
4356 
4357     return err;
4358 }
4359 
4360 /**
4361  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4362  */
4363 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4364     va_list argptr;
4365     va_start(argptr, cmd);
4366     int res = hci_send_cmd_va_arg(cmd, argptr);
4367     va_end(argptr);
4368     return res;
4369 }
4370 
4371 // Create various non-HCI events.
4372 // TODO: generalize, use table similar to hci_create_command
4373 
4374 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4375     // dump packet
4376     if (dump) {
4377         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4378     }
4379 
4380     // dispatch to all event handlers
4381     btstack_linked_list_iterator_t it;
4382     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4383     while (btstack_linked_list_iterator_has_next(&it)){
4384         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4385         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4386     }
4387 }
4388 
4389 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4390     if (!hci_stack->acl_packet_handler) return;
4391     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4392 }
4393 
4394 #ifdef ENABLE_CLASSIC
4395 static void hci_notify_if_sco_can_send_now(void){
4396     // notify SCO sender if waiting
4397     if (!hci_stack->sco_waiting_for_can_send_now) return;
4398     if (hci_can_send_sco_packet_now()){
4399         hci_stack->sco_waiting_for_can_send_now = 0;
4400         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4401         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4402         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4403     }
4404 }
4405 
4406 // parsing end emitting has been merged to reduce code size
4407 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4408     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4409 
4410     uint8_t * eir_data;
4411     ad_context_t context;
4412     const uint8_t * name;
4413     uint8_t         name_len;
4414 
4415     if (size < 3) return;
4416 
4417     int event_type = hci_event_packet_get_type(packet);
4418     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4419     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4420 
4421     switch (event_type){
4422         case HCI_EVENT_INQUIRY_RESULT:
4423         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4424             if (size != (3 + (num_responses * 14))) return;
4425             break;
4426         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4427             if (size != 257) return;
4428             if (num_responses != 1) return;
4429             break;
4430         default:
4431             return;
4432     }
4433 
4434     // event[1] is set at the end
4435     int i;
4436     for (i=0; i<num_responses;i++){
4437         memset(event, 0, sizeof(event));
4438         event[0] = GAP_EVENT_INQUIRY_RESULT;
4439         uint8_t event_size = 18;    // if name is not set by EIR
4440 
4441         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4442         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4443         (void)memcpy(&event[9],
4444                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4445                      3); // class of device
4446         (void)memcpy(&event[12],
4447                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4448                      2); // clock offset
4449 
4450         switch (event_type){
4451             case HCI_EVENT_INQUIRY_RESULT:
4452                 // 14,15,16,17 = 0, size 18
4453                 break;
4454             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4455                 event[14] = 1;
4456                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4457                 // 16,17 = 0, size 18
4458                 break;
4459             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4460                 event[14] = 1;
4461                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4462                 // EIR packets only contain a single inquiry response
4463                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4464                 name = NULL;
4465                 // Iterate over EIR data
4466                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4467                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4468                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4469                     const uint8_t * data = ad_iterator_get_data(&context);
4470                     // Prefer Complete Local Name over Shortend Local Name
4471                     switch (data_type){
4472                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4473                             if (name) continue;
4474                             /* fall through */
4475                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4476                             name = data;
4477                             name_len = data_size;
4478                             break;
4479                         default:
4480                             break;
4481                     }
4482                 }
4483                 if (name){
4484                     event[16] = 1;
4485                     // truncate name if needed
4486                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4487                     event[17] = len;
4488                     (void)memcpy(&event[18], name, len);
4489                     event_size += len;
4490                 }
4491                 break;
4492         }
4493         event[1] = event_size - 2;
4494         hci_emit_event(event, event_size, 1);
4495     }
4496 }
4497 #endif
4498 
4499 void hci_emit_state(void){
4500     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4501     uint8_t event[3];
4502     event[0] = BTSTACK_EVENT_STATE;
4503     event[1] = sizeof(event) - 2;
4504     event[2] = hci_stack->state;
4505     hci_emit_event(event, sizeof(event), 1);
4506 }
4507 
4508 #ifdef ENABLE_CLASSIC
4509 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4510     uint8_t event[13];
4511     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4512     event[1] = sizeof(event) - 2;
4513     event[2] = status;
4514     little_endian_store_16(event, 3, con_handle);
4515     reverse_bd_addr(address, &event[5]);
4516     event[11] = 1; // ACL connection
4517     event[12] = 0; // encryption disabled
4518     hci_emit_event(event, sizeof(event), 1);
4519 }
4520 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4521     if (disable_l2cap_timeouts) return;
4522     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4523     uint8_t event[4];
4524     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4525     event[1] = sizeof(event) - 2;
4526     little_endian_store_16(event, 2, conn->con_handle);
4527     hci_emit_event(event, sizeof(event), 1);
4528 }
4529 #endif
4530 
4531 #ifdef ENABLE_BLE
4532 #ifdef ENABLE_LE_CENTRAL
4533 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4534     uint8_t event[21];
4535     event[0] = HCI_EVENT_LE_META;
4536     event[1] = sizeof(event) - 2;
4537     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4538     event[3] = status;
4539     little_endian_store_16(event, 4, con_handle);
4540     event[6] = 0; // TODO: role
4541     event[7] = address_type;
4542     reverse_bd_addr(address, &event[8]);
4543     little_endian_store_16(event, 14, 0); // interval
4544     little_endian_store_16(event, 16, 0); // latency
4545     little_endian_store_16(event, 18, 0); // supervision timeout
4546     event[20] = 0; // master clock accuracy
4547     hci_emit_event(event, sizeof(event), 1);
4548 }
4549 #endif
4550 #endif
4551 
4552 static void hci_emit_transport_packet_sent(void){
4553     // notify upper stack that it might be possible to send again
4554     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4555     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4556 }
4557 
4558 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4559     uint8_t event[6];
4560     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4561     event[1] = sizeof(event) - 2;
4562     event[2] = 0; // status = OK
4563     little_endian_store_16(event, 3, con_handle);
4564     event[5] = reason;
4565     hci_emit_event(event, sizeof(event), 1);
4566 }
4567 
4568 static void hci_emit_nr_connections_changed(void){
4569     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4570     uint8_t event[3];
4571     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4572     event[1] = sizeof(event) - 2;
4573     event[2] = nr_hci_connections();
4574     hci_emit_event(event, sizeof(event), 1);
4575 }
4576 
4577 static void hci_emit_hci_open_failed(void){
4578     log_info("BTSTACK_EVENT_POWERON_FAILED");
4579     uint8_t event[2];
4580     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4581     event[1] = sizeof(event) - 2;
4582     hci_emit_event(event, sizeof(event), 1);
4583 }
4584 
4585 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4586     log_info("hci_emit_dedicated_bonding_result %u ", status);
4587     uint8_t event[9];
4588     int pos = 0;
4589     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4590     event[pos++] = sizeof(event) - 2;
4591     event[pos++] = status;
4592     reverse_bd_addr(address, &event[pos]);
4593     hci_emit_event(event, sizeof(event), 1);
4594 }
4595 
4596 
4597 #ifdef ENABLE_CLASSIC
4598 
4599 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4600     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4601     uint8_t event[5];
4602     int pos = 0;
4603     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4604     event[pos++] = sizeof(event) - 2;
4605     little_endian_store_16(event, 2, con_handle);
4606     pos += 2;
4607     event[pos++] = level;
4608     hci_emit_event(event, sizeof(event), 1);
4609 }
4610 
4611 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4612     if (!connection) return LEVEL_0;
4613     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4614     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4615     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4616     // LEVEL 4 always requires 128 bit encrytion key size
4617     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4618         security_level = LEVEL_3;
4619     }
4620     return security_level;
4621 }
4622 
4623 static void hci_emit_discoverable_enabled(uint8_t enabled){
4624     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4625     uint8_t event[3];
4626     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4627     event[1] = sizeof(event) - 2;
4628     event[2] = enabled;
4629     hci_emit_event(event, sizeof(event), 1);
4630 }
4631 
4632 // query if remote side supports eSCO
4633 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4634     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4635     if (!connection) return 0;
4636     return (connection->remote_supported_features[0] & 1) != 0;
4637 }
4638 
4639 static bool hci_ssp_supported(hci_connection_t * connection){
4640     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4641     return (connection->bonding_flags & mask) == mask;
4642 }
4643 
4644 // query if remote side supports SSP
4645 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4646     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4647     if (!connection) return 0;
4648     return hci_ssp_supported(connection) ? 1 : 0;
4649 }
4650 
4651 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4652     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4653 }
4654 
4655 // GAP API
4656 /**
4657  * @bbrief enable/disable bonding. default is enabled
4658  * @praram enabled
4659  */
4660 void gap_set_bondable_mode(int enable){
4661     hci_stack->bondable = enable ? 1 : 0;
4662 }
4663 /**
4664  * @brief Get bondable mode.
4665  * @return 1 if bondable
4666  */
4667 int gap_get_bondable_mode(void){
4668     return hci_stack->bondable;
4669 }
4670 
4671 /**
4672  * @brief map link keys to security levels
4673  */
4674 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4675     switch (link_key_type){
4676         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4677             return LEVEL_4;
4678         case COMBINATION_KEY:
4679         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4680             return LEVEL_3;
4681         default:
4682             return LEVEL_2;
4683     }
4684 }
4685 
4686 /**
4687  * @brief map link keys to secure connection yes/no
4688  */
4689 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4690     switch (link_key_type){
4691         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4692         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4693             return 1;
4694         default:
4695             return 0;
4696     }
4697 }
4698 
4699 /**
4700  * @brief map link keys to authenticated
4701  */
4702 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4703     switch (link_key_type){
4704         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4705         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4706             return 1;
4707         default:
4708             return 0;
4709     }
4710 }
4711 
4712 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4713     log_info("gap_mitm_protection_required_for_security_level %u", level);
4714     return level > LEVEL_2;
4715 }
4716 
4717 /**
4718  * @brief get current security level
4719  */
4720 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4721     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4722     if (!connection) return LEVEL_0;
4723     return gap_security_level_for_connection(connection);
4724 }
4725 
4726 /**
4727  * @brief request connection to device to
4728  * @result GAP_AUTHENTICATION_RESULT
4729  */
4730 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4731     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4732     if (!connection){
4733         hci_emit_security_level(con_handle, LEVEL_0);
4734         return;
4735     }
4736     gap_security_level_t current_level = gap_security_level(con_handle);
4737     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4738         requested_level, connection->requested_security_level, current_level);
4739 
4740     // assumption: earlier requested security higher than current level => security request is active
4741     if (current_level < connection->requested_security_level){
4742         if (connection->requested_security_level < requested_level){
4743             // increase requested level as new level is higher
4744 
4745             // TODO: handle re-authentication when done
4746 
4747             connection->requested_security_level = requested_level;
4748         }
4749         return;
4750     }
4751 
4752     // no request active, notify if security sufficient
4753     if (requested_level <= current_level){
4754         hci_emit_security_level(con_handle, current_level);
4755         return;
4756     }
4757 
4758     // start pairing to increase security level
4759     connection->requested_security_level = requested_level;
4760 
4761 #if 0
4762     // sending encryption request without a link key results in an error.
4763     // TODO: figure out how to use it properly
4764 
4765     // would enabling ecnryption suffice (>= LEVEL_2)?
4766     if (hci_stack->link_key_db){
4767         link_key_type_t link_key_type;
4768         link_key_t      link_key;
4769         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4770             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4771                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4772                 return;
4773             }
4774         }
4775     }
4776 #endif
4777 
4778     // start to authenticate connection
4779     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4780     hci_run();
4781 }
4782 
4783 /**
4784  * @brief start dedicated bonding with device. disconnect after bonding
4785  * @param device
4786  * @param request MITM protection
4787  * @result GAP_DEDICATED_BONDING_COMPLETE
4788  */
4789 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4790 
4791     // create connection state machine
4792     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4793 
4794     if (!connection){
4795         return BTSTACK_MEMORY_ALLOC_FAILED;
4796     }
4797 
4798     // delete linkn key
4799     gap_drop_link_key_for_bd_addr(device);
4800 
4801     // configure LEVEL_2/3, dedicated bonding
4802     connection->state = SEND_CREATE_CONNECTION;
4803     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4804     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4805     connection->bonding_flags = BONDING_DEDICATED;
4806 
4807     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4808 
4809     // handle: connnection failure (connection complete != ok)
4810     // handle: authentication failure
4811     // handle: disconnect on done
4812 
4813     hci_run();
4814 
4815     return 0;
4816 }
4817 #endif
4818 
4819 void gap_set_local_name(const char * local_name){
4820     hci_stack->local_name = local_name;
4821 }
4822 
4823 
4824 #ifdef ENABLE_BLE
4825 
4826 #ifdef ENABLE_LE_CENTRAL
4827 void gap_start_scan(void){
4828     hci_stack->le_scanning_enabled = 1;
4829     hci_run();
4830 }
4831 
4832 void gap_stop_scan(void){
4833     hci_stack->le_scanning_enabled = 0;
4834     hci_run();
4835 }
4836 
4837 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4838     hci_stack->le_scan_type     = scan_type;
4839     hci_stack->le_scan_interval = scan_interval;
4840     hci_stack->le_scan_window   = scan_window;
4841     hci_run();
4842 }
4843 
4844 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4845     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4846     if (!conn){
4847         log_info("gap_connect: no connection exists yet, creating context");
4848         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4849         if (!conn){
4850             // notify client that alloc failed
4851             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4852             log_info("gap_connect: failed to alloc hci_connection_t");
4853             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4854         }
4855         conn->state = SEND_CREATE_CONNECTION;
4856         log_info("gap_connect: send create connection next");
4857         hci_run();
4858         return ERROR_CODE_SUCCESS;
4859     }
4860 
4861     if (!hci_is_le_connection(conn) ||
4862         (conn->state == SEND_CREATE_CONNECTION) ||
4863         (conn->state == SENT_CREATE_CONNECTION)) {
4864         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4865         log_error("gap_connect: classic connection or connect is already being created");
4866         return GATT_CLIENT_IN_WRONG_STATE;
4867     }
4868 
4869     // check if connection was just disconnected
4870     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4871         log_info("gap_connect: send create connection (again)");
4872         conn->state = SEND_CREATE_CONNECTION;
4873         hci_run();
4874         return ERROR_CODE_SUCCESS;
4875     }
4876 
4877     log_info("gap_connect: context exists with state %u", conn->state);
4878     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4879     hci_run();
4880     return ERROR_CODE_SUCCESS;
4881 }
4882 
4883 // @assumption: only a single outgoing LE Connection exists
4884 static hci_connection_t * gap_get_outgoing_connection(void){
4885     btstack_linked_item_t *it;
4886     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4887         hci_connection_t * conn = (hci_connection_t *) it;
4888         if (!hci_is_le_connection(conn)) continue;
4889         switch (conn->state){
4890             case SEND_CREATE_CONNECTION:
4891             case SENT_CREATE_CONNECTION:
4892             case SENT_CANCEL_CONNECTION:
4893                 return conn;
4894             default:
4895                 break;
4896         };
4897     }
4898     return NULL;
4899 }
4900 
4901 uint8_t gap_connect_cancel(void){
4902     hci_connection_t * conn = gap_get_outgoing_connection();
4903     if (!conn) return 0;
4904     switch (conn->state){
4905         case SEND_CREATE_CONNECTION:
4906             // skip sending create connection and emit event instead
4907             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4908             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4909             btstack_memory_hci_connection_free( conn );
4910             break;
4911         case SENT_CREATE_CONNECTION:
4912             // request to send cancel connection
4913             conn->state = SEND_CANCEL_CONNECTION;
4914             hci_run();
4915             break;
4916         default:
4917             break;
4918     }
4919     return 0;
4920 }
4921 #endif
4922 
4923 #ifdef ENABLE_LE_CENTRAL
4924 /**
4925  * @brief Set connection parameters for outgoing connections
4926  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4927  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4928  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4929  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4930  * @param conn_latency, default: 4
4931  * @param supervision_timeout (unit: 10ms), default: 720 ms
4932  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4933  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4934  */
4935 
4936 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4937     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4938     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4939     hci_stack->le_connection_scan_interval = conn_scan_interval;
4940     hci_stack->le_connection_scan_window = conn_scan_window;
4941     hci_stack->le_connection_interval_min = conn_interval_min;
4942     hci_stack->le_connection_interval_max = conn_interval_max;
4943     hci_stack->le_connection_latency = conn_latency;
4944     hci_stack->le_supervision_timeout = supervision_timeout;
4945     hci_stack->le_minimum_ce_length = min_ce_length;
4946     hci_stack->le_maximum_ce_length = max_ce_length;
4947 }
4948 #endif
4949 
4950 /**
4951  * @brief Updates the connection parameters for a given LE connection
4952  * @param handle
4953  * @param conn_interval_min (unit: 1.25ms)
4954  * @param conn_interval_max (unit: 1.25ms)
4955  * @param conn_latency
4956  * @param supervision_timeout (unit: 10ms)
4957  * @returns 0 if ok
4958  */
4959 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4960     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4961     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4962     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4963     connection->le_conn_interval_min = conn_interval_min;
4964     connection->le_conn_interval_max = conn_interval_max;
4965     connection->le_conn_latency = conn_latency;
4966     connection->le_supervision_timeout = supervision_timeout;
4967     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4968     hci_run();
4969     return 0;
4970 }
4971 
4972 /**
4973  * @brief Request an update of the connection parameter for a given LE connection
4974  * @param handle
4975  * @param conn_interval_min (unit: 1.25ms)
4976  * @param conn_interval_max (unit: 1.25ms)
4977  * @param conn_latency
4978  * @param supervision_timeout (unit: 10ms)
4979  * @returns 0 if ok
4980  */
4981 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4982     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4983     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4984     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4985     connection->le_conn_interval_min = conn_interval_min;
4986     connection->le_conn_interval_max = conn_interval_max;
4987     connection->le_conn_latency = conn_latency;
4988     connection->le_supervision_timeout = supervision_timeout;
4989     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4990     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4991     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4992     return 0;
4993 }
4994 
4995 #ifdef ENABLE_LE_PERIPHERAL
4996 
4997 static void gap_advertisments_changed(void){
4998     // disable advertisements before updating adv, scan data, or adv params
4999     if (hci_stack->le_advertisements_active){
5000         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
5001     }
5002     hci_run();
5003 }
5004 
5005 /**
5006  * @brief Set Advertisement Data
5007  * @param advertising_data_length
5008  * @param advertising_data (max 31 octets)
5009  * @note data is not copied, pointer has to stay valid
5010  */
5011 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5012     hci_stack->le_advertisements_data_len = advertising_data_length;
5013     hci_stack->le_advertisements_data = advertising_data;
5014     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5015     gap_advertisments_changed();
5016 }
5017 
5018 /**
5019  * @brief Set Scan Response Data
5020  * @param advertising_data_length
5021  * @param advertising_data (max 31 octets)
5022  * @note data is not copied, pointer has to stay valid
5023  */
5024 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5025     hci_stack->le_scan_response_data_len = scan_response_data_length;
5026     hci_stack->le_scan_response_data = scan_response_data;
5027     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5028     gap_advertisments_changed();
5029 }
5030 
5031 /**
5032  * @brief Set Advertisement Parameters
5033  * @param adv_int_min
5034  * @param adv_int_max
5035  * @param adv_type
5036  * @param direct_address_type
5037  * @param direct_address
5038  * @param channel_map
5039  * @param filter_policy
5040  *
5041  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5042  */
5043  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5044     uint8_t direct_address_typ, bd_addr_t direct_address,
5045     uint8_t channel_map, uint8_t filter_policy) {
5046 
5047     hci_stack->le_advertisements_interval_min = adv_int_min;
5048     hci_stack->le_advertisements_interval_max = adv_int_max;
5049     hci_stack->le_advertisements_type = adv_type;
5050     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5051     hci_stack->le_advertisements_channel_map = channel_map;
5052     hci_stack->le_advertisements_filter_policy = filter_policy;
5053     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5054                  6);
5055 
5056     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5057     gap_advertisments_changed();
5058  }
5059 
5060 /**
5061  * @brief Enable/Disable Advertisements
5062  * @param enabled
5063  */
5064 void gap_advertisements_enable(int enabled){
5065     hci_stack->le_advertisements_enabled = enabled;
5066     if (enabled && !hci_stack->le_advertisements_active){
5067         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
5068     }
5069     if (!enabled && hci_stack->le_advertisements_active){
5070         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
5071     }
5072     hci_run();
5073 }
5074 
5075 #endif
5076 
5077 void hci_le_set_own_address_type(uint8_t own_address_type){
5078     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5079     if (own_address_type == hci_stack->le_own_addr_type) return;
5080     hci_stack->le_own_addr_type = own_address_type;
5081 
5082 #ifdef ENABLE_LE_PERIPHERAL
5083     // update advertisement parameters, too
5084     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5085     gap_advertisments_changed();
5086 #endif
5087 #ifdef ENABLE_LE_CENTRAL
5088     // note: we don't update scan parameters or modify ongoing connection attempts
5089 #endif
5090 }
5091 
5092 #endif
5093 
5094 uint8_t gap_disconnect(hci_con_handle_t handle){
5095     hci_connection_t * conn = hci_connection_for_handle(handle);
5096     if (!conn){
5097         hci_emit_disconnection_complete(handle, 0);
5098         return 0;
5099     }
5100     // ignore if already disconnected
5101     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5102         return 0;
5103     }
5104     conn->state = SEND_DISCONNECT;
5105     hci_run();
5106     return 0;
5107 }
5108 
5109 int gap_read_rssi(hci_con_handle_t con_handle){
5110     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5111     if (hci_connection == NULL) return 0;
5112     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5113     hci_run();
5114     return 1;
5115 }
5116 
5117 /**
5118  * @brief Get connection type
5119  * @param con_handle
5120  * @result connection_type
5121  */
5122 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5123     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5124     if (!conn) return GAP_CONNECTION_INVALID;
5125     switch (conn->address_type){
5126         case BD_ADDR_TYPE_LE_PUBLIC:
5127         case BD_ADDR_TYPE_LE_RANDOM:
5128             return GAP_CONNECTION_LE;
5129         case BD_ADDR_TYPE_SCO:
5130             return GAP_CONNECTION_SCO;
5131         case BD_ADDR_TYPE_ACL:
5132             return GAP_CONNECTION_ACL;
5133         default:
5134             return GAP_CONNECTION_INVALID;
5135     }
5136 }
5137 
5138 #ifdef ENABLE_BLE
5139 
5140 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){
5141     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5142     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5143 
5144     conn->le_phy_update_all_phys    = all_phys;
5145     conn->le_phy_update_tx_phys     = tx_phys;
5146     conn->le_phy_update_rx_phys     = rx_phys;
5147     conn->le_phy_update_phy_options = phy_options;
5148 
5149     hci_run();
5150 
5151     return 0;
5152 }
5153 
5154 #ifdef ENABLE_LE_CENTRAL
5155 /**
5156  * @brief Auto Connection Establishment - Start Connecting to device
5157  * @param address_typ
5158  * @param address
5159  * @returns 0 if ok
5160  */
5161 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5162     // check capacity
5163     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5164     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5165     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5166     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5167     entry->address_type = address_type;
5168     (void)memcpy(entry->address, address, 6);
5169     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5170     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5171     hci_run();
5172     return 0;
5173 }
5174 
5175 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5176     btstack_linked_list_iterator_t it;
5177     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5178     while (btstack_linked_list_iterator_has_next(&it)){
5179         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5180         if (entry->address_type != address_type) continue;
5181         if (memcmp(entry->address, address, 6) != 0) continue;
5182         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5183             // remove from controller if already present
5184             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5185             continue;
5186         }
5187         // direclty remove entry from whitelist
5188         btstack_linked_list_iterator_remove(&it);
5189         btstack_memory_whitelist_entry_free(entry);
5190     }
5191 }
5192 
5193 /**
5194  * @brief Auto Connection Establishment - Stop Connecting to device
5195  * @param address_typ
5196  * @param address
5197  * @returns 0 if ok
5198  */
5199 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5200     hci_remove_from_whitelist(address_type, address);
5201     hci_run();
5202     return 0;
5203 }
5204 
5205 /**
5206  * @brief Auto Connection Establishment - Stop everything
5207  * @note  Convenience function to stop all active auto connection attempts
5208  */
5209 void gap_auto_connection_stop_all(void){
5210     btstack_linked_list_iterator_t it;
5211     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5212     while (btstack_linked_list_iterator_has_next(&it)){
5213         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5214         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5215             // remove from controller if already present
5216             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5217             continue;
5218         }
5219         // directly remove entry from whitelist
5220         btstack_linked_list_iterator_remove(&it);
5221         btstack_memory_whitelist_entry_free(entry);
5222     }
5223     hci_run();
5224 }
5225 
5226 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5227     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5228     if (!conn) return 0;
5229     return conn->le_connection_interval;
5230 }
5231 #endif
5232 #endif
5233 
5234 #ifdef ENABLE_CLASSIC
5235 /**
5236  * @brief Set Extended Inquiry Response data
5237  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5238  * @note has to be done before stack starts up
5239  */
5240 void gap_set_extended_inquiry_response(const uint8_t * data){
5241     hci_stack->eir_data = data;
5242 }
5243 
5244 /**
5245  * @brief Start GAP Classic Inquiry
5246  * @param duration in 1.28s units
5247  * @return 0 if ok
5248  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5249  */
5250 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5251     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5252     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5253     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5254         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5255     }
5256     hci_stack->inquiry_state = duration_in_1280ms_units;
5257     hci_run();
5258     return 0;
5259 }
5260 
5261 /**
5262  * @brief Stop GAP Classic Inquiry
5263  * @returns 0 if ok
5264  */
5265 int gap_inquiry_stop(void){
5266     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5267         // emit inquiry complete event, before it even started
5268         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5269         hci_emit_event(event, sizeof(event), 1);
5270         return 0;
5271     }
5272     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5273     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5274     hci_run();
5275     return 0;
5276 }
5277 
5278 
5279 /**
5280  * @brief Remote Name Request
5281  * @param addr
5282  * @param page_scan_repetition_mode
5283  * @param clock_offset only used when bit 15 is set
5284  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5285  */
5286 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5287     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5288     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5289     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5290     hci_stack->remote_name_clock_offset = clock_offset;
5291     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5292     hci_run();
5293     return 0;
5294 }
5295 
5296 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5297     hci_stack->gap_pairing_state = state;
5298     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5299     hci_run();
5300     return 0;
5301 }
5302 
5303 /**
5304  * @brief Legacy Pairing Pin Code Response
5305  * @param addr
5306  * @param pin
5307  * @return 0 if ok
5308  */
5309 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5310     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5311     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5312     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5313 }
5314 
5315 /**
5316  * @brief Abort Legacy Pairing
5317  * @param addr
5318  * @param pin
5319  * @return 0 if ok
5320  */
5321 int gap_pin_code_negative(bd_addr_t addr){
5322     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5323     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5324 }
5325 
5326 /**
5327  * @brief SSP Passkey Response
5328  * @param addr
5329  * @param passkey
5330  * @return 0 if ok
5331  */
5332 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5333     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5334     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5335     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5336 }
5337 
5338 /**
5339  * @brief Abort SSP Passkey Entry/Pairing
5340  * @param addr
5341  * @param pin
5342  * @return 0 if ok
5343  */
5344 int gap_ssp_passkey_negative(bd_addr_t addr){
5345     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5346     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5347 }
5348 
5349 /**
5350  * @brief Accept SSP Numeric Comparison
5351  * @param addr
5352  * @param passkey
5353  * @return 0 if ok
5354  */
5355 int gap_ssp_confirmation_response(bd_addr_t addr){
5356     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5357     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5358 }
5359 
5360 /**
5361  * @brief Abort SSP Numeric Comparison/Pairing
5362  * @param addr
5363  * @param pin
5364  * @return 0 if ok
5365  */
5366 int gap_ssp_confirmation_negative(bd_addr_t addr){
5367     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5368     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5369 }
5370 
5371 /**
5372  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5373  * @param inquiry_mode see bluetooth_defines.h
5374  */
5375 void hci_set_inquiry_mode(inquiry_mode_t mode){
5376     hci_stack->inquiry_mode = mode;
5377 }
5378 
5379 /**
5380  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5381  */
5382 void hci_set_sco_voice_setting(uint16_t voice_setting){
5383     hci_stack->sco_voice_setting = voice_setting;
5384 }
5385 
5386 /**
5387  * @brief Get SCO Voice Setting
5388  * @return current voice setting
5389  */
5390 uint16_t hci_get_sco_voice_setting(void){
5391     return hci_stack->sco_voice_setting;
5392 }
5393 
5394 static int hci_have_usb_transport(void){
5395     if (!hci_stack->hci_transport) return 0;
5396     const char * transport_name = hci_stack->hci_transport->name;
5397     if (!transport_name) return 0;
5398     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5399 }
5400 
5401 /** @brief Get SCO packet length for current SCO Voice setting
5402  *  @note  Using SCO packets of the exact length is required for USB transfer
5403  *  @return Length of SCO packets in bytes (not audio frames)
5404  */
5405 int hci_get_sco_packet_length(void){
5406     int sco_packet_length = 0;
5407 
5408 #ifdef ENABLE_SCO_OVER_HCI
5409 
5410     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5411     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5412 
5413     if (hci_have_usb_transport()){
5414         // see Core Spec for H2 USB Transfer.
5415         // 3 byte SCO header + 24 bytes per connection
5416         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5417         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5418     } else {
5419         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5420         sco_packet_length = 3 + 60 * multiplier;
5421         // assert that it still fits inside an SCO buffer
5422         if (sco_packet_length > hci_stack->sco_data_packet_length){
5423             sco_packet_length = 3 + 60;
5424         }
5425     }
5426 #endif
5427     return sco_packet_length;
5428 }
5429 
5430 /**
5431 * @brief Sets the master/slave policy
5432 * @param policy (0: attempt to become master, 1: let connecting device decide)
5433 */
5434 void hci_set_master_slave_policy(uint8_t policy){
5435     hci_stack->master_slave_policy = policy;
5436 }
5437 
5438 #endif
5439 
5440 HCI_STATE hci_get_state(void){
5441     return hci_stack->state;
5442 }
5443 
5444 #ifdef ENABLE_CLASSIC
5445 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5446     hci_stack->gap_classic_accept_callback = accept_callback;
5447 }
5448 #endif
5449 
5450 /**
5451  * @brief Set callback for Bluetooth Hardware Error
5452  */
5453 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5454     hci_stack->hardware_error_callback = fn;
5455 }
5456 
5457 void hci_disconnect_all(void){
5458     btstack_linked_list_iterator_t it;
5459     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5460     while (btstack_linked_list_iterator_has_next(&it)){
5461         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5462         if (con->state == SENT_DISCONNECT) continue;
5463         con->state = SEND_DISCONNECT;
5464     }
5465     hci_run();
5466 }
5467 
5468 uint16_t hci_get_manufacturer(void){
5469     return hci_stack->manufacturer;
5470 }
5471 
5472 #ifdef ENABLE_BLE
5473 
5474 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5475     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5476     if (!hci_con) return NULL;
5477     return &hci_con->sm_connection;
5478 }
5479 
5480 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5481 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5482 
5483 int gap_encryption_key_size(hci_con_handle_t con_handle){
5484     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5485     if (hci_connection == NULL) return 0;
5486     if (hci_is_le_connection(hci_connection)){
5487         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5488         if (sm_conn->sm_connection_encrypted) {
5489             return sm_conn->sm_actual_encryption_key_size;
5490         }
5491     }
5492 #ifdef ENABLE_CLASSIC
5493     else {
5494         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5495             return hci_connection->encryption_key_size;
5496         }
5497     }
5498 #endif
5499     return 0;
5500 }
5501 
5502 int gap_authenticated(hci_con_handle_t con_handle){
5503     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5504     if (hci_connection == NULL) return 0;
5505 
5506     switch (hci_connection->address_type){
5507         case BD_ADDR_TYPE_LE_PUBLIC:
5508         case BD_ADDR_TYPE_LE_RANDOM:
5509             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5510             return hci_connection->sm_connection.sm_connection_authenticated;
5511 #ifdef ENABLE_CLASSIC
5512         case BD_ADDR_TYPE_SCO:
5513         case BD_ADDR_TYPE_ACL:
5514             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5515 #endif
5516         default:
5517             return 0;
5518     }
5519 }
5520 
5521 int gap_secure_connection(hci_con_handle_t con_handle){
5522     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5523     if (hci_connection == NULL) return 0;
5524 
5525     switch (hci_connection->address_type){
5526         case BD_ADDR_TYPE_LE_PUBLIC:
5527         case BD_ADDR_TYPE_LE_RANDOM:
5528             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5529             return hci_connection->sm_connection.sm_connection_sc;
5530 #ifdef ENABLE_CLASSIC
5531         case BD_ADDR_TYPE_SCO:
5532         case BD_ADDR_TYPE_ACL:
5533             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5534 #endif
5535         default:
5536             return 0;
5537     }
5538 }
5539 
5540 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5541     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5542     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5543     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5544     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5545     return sm_conn->sm_connection_authorization_state;
5546 }
5547 #endif
5548 
5549 #ifdef ENABLE_CLASSIC
5550 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){
5551     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5552     if (!conn) return GAP_CONNECTION_INVALID;
5553     conn->sniff_min_interval = sniff_min_interval;
5554     conn->sniff_max_interval = sniff_max_interval;
5555     conn->sniff_attempt = sniff_attempt;
5556     conn->sniff_timeout = sniff_timeout;
5557     hci_run();
5558     return 0;
5559 }
5560 
5561 /**
5562  * @brief Exit Sniff mode
5563  * @param con_handle
5564  @ @return 0 if ok
5565  */
5566 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5567     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5568     if (!conn) return GAP_CONNECTION_INVALID;
5569     conn->sniff_min_interval = 0xffff;
5570     hci_run();
5571     return 0;
5572 }
5573 #endif
5574 
5575 void hci_halting_defer(void){
5576     if (hci_stack->state != HCI_STATE_HALTING) return;
5577     switch (hci_stack->substate){
5578         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5579         case HCI_HALTING_CLOSE:
5580             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5581             break;
5582         default:
5583             break;
5584     }
5585 }
5586 
5587 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5588 void hci_setup_test_connections_fuzz(void){
5589     hci_connection_t * conn;
5590 
5591     // default address: 66:55:44:33:00:01
5592     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5593 
5594     // setup Controller info
5595     hci_stack->num_cmd_packets = 255;
5596     hci_stack->acl_packets_total_num = 255;
5597 
5598     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5599     addr[5] = 0x01;
5600     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5601     conn->con_handle = addr[5];
5602     conn->role  = HCI_ROLE_SLAVE;
5603     conn->state = RECEIVED_CONNECTION_REQUEST;
5604     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5605 
5606     // setup incoming Classic SCO connection with con handle 0x0002
5607     addr[5] = 0x02;
5608     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5609     conn->con_handle = addr[5];
5610     conn->role  = HCI_ROLE_SLAVE;
5611     conn->state = RECEIVED_CONNECTION_REQUEST;
5612     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5613 
5614     // setup ready Classic ACL connection with con handle 0x0003
5615     addr[5] = 0x03;
5616     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5617     conn->con_handle = addr[5];
5618     conn->role  = HCI_ROLE_SLAVE;
5619     conn->state = OPEN;
5620     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5621 
5622     // setup ready Classic SCO connection with con handle 0x0004
5623     addr[5] = 0x04;
5624     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5625     conn->con_handle = addr[5];
5626     conn->role  = HCI_ROLE_SLAVE;
5627     conn->state = OPEN;
5628     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5629 
5630     // setup ready LE ACL connection with con handle 0x005 and public address
5631     addr[5] = 0x05;
5632     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5633     conn->con_handle = addr[5];
5634     conn->role  = HCI_ROLE_SLAVE;
5635     conn->state = OPEN;
5636     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5637 }
5638 
5639 void hci_free_connections_fuzz(void){
5640     btstack_linked_list_iterator_t it;
5641     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5642     while (btstack_linked_list_iterator_has_next(&it)){
5643         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5644         btstack_linked_list_iterator_remove(&it);
5645         btstack_memory_hci_connection_free(con);
5646     }
5647 }
5648 void hci_simulate_working_fuzz(void){
5649     hci_init_done();
5650     hci_stack->num_cmd_packets = 255;
5651 }
5652 #endif
5653