xref: /btstack/src/hci.c (revision 77208d90205dc3c436e52c037cf12aa50863eaf0)
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 #include "ble/le_device_db.h"
63 #endif
64 
65 #include <stdarg.h>
66 #include <string.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 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
97 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM."
98 #endif
99 
100 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
101 #error "SCO data can either be routed over HCI or over PCM, but not over both. Please only enable ENABLE_SCO_OVER_HCI or HAVE_SCO_TRANSPORT."
102 #endif
103 
104 #define HCI_CONNECTION_TIMEOUT_MS 10000
105 
106 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
107 #define HCI_RESET_RESEND_TIMEOUT_MS 200
108 #endif
109 
110 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
111 #ifndef GAP_INQUIRY_MAX_NAME_LEN
112 #define GAP_INQUIRY_MAX_NAME_LEN 32
113 #endif
114 
115 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
116 #define GAP_INQUIRY_DURATION_MIN       0x01
117 #define GAP_INQUIRY_DURATION_MAX       0x30
118 #define GAP_INQUIRY_STATE_IDLE         0x00
119 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
120 #define GAP_INQUIRY_STATE_ACTIVE       0x81
121 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
122 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
123 
124 // GAP Remote Name Request
125 #define GAP_REMOTE_NAME_STATE_IDLE 0
126 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
127 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
128 
129 // GAP Pairing
130 #define GAP_PAIRING_STATE_IDLE                       0
131 #define GAP_PAIRING_STATE_SEND_PIN                   1
132 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
133 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
134 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
135 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
136 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
137 
138 
139 // prototypes
140 #ifdef ENABLE_CLASSIC
141 static void hci_update_scan_enable(void);
142 static void hci_emit_discoverable_enabled(uint8_t enabled);
143 static int  hci_local_ssp_activated(void);
144 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
145 static bool hci_ssp_supported(hci_connection_t * connection);
146 static void hci_notify_if_sco_can_send_now(void);
147 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
148 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
149 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
150 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
151 static void hci_connection_timestamp(hci_connection_t *connection);
152 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
153 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
154 #endif
155 
156 static int  hci_power_control_on(void);
157 static void hci_power_control_off(void);
158 static void hci_state_reset(void);
159 static void hci_emit_transport_packet_sent(void);
160 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
161 static void hci_emit_nr_connections_changed(void);
162 static void hci_emit_hci_open_failed(void);
163 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
164 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
165 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
166 static void hci_run(void);
167 static int  hci_is_le_connection(hci_connection_t * connection);
168 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
169 
170 #ifdef ENABLE_CLASSIC
171 static int hci_have_usb_transport(void);
172 #endif
173 
174 #ifdef ENABLE_BLE
175 #ifdef ENABLE_LE_CENTRAL
176 // called from test/ble_client/advertising_data_parser.c
177 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
178 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
179 static hci_connection_t * gap_get_outgoing_connection(void);
180 #endif
181 #endif
182 
183 // the STACK is here
184 #ifndef HAVE_MALLOC
185 static hci_stack_t   hci_stack_static;
186 #endif
187 static hci_stack_t * hci_stack = NULL;
188 
189 #ifdef ENABLE_CLASSIC
190 // default name
191 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
192 
193 // test helper
194 static uint8_t disable_l2cap_timeouts = 0;
195 #endif
196 
197 /**
198  * create connection for given address
199  *
200  * @return connection OR NULL, if no memory left
201  */
202 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
203     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
204     hci_connection_t * conn = btstack_memory_hci_connection_get();
205     if (!conn) return NULL;
206     bd_addr_copy(conn->address, addr);
207     conn->role = HCI_ROLE_INVALID;
208     conn->address_type = addr_type;
209     conn->con_handle = 0xffff;
210     conn->authentication_flags = AUTH_FLAGS_NONE;
211     conn->bonding_flags = 0;
212     conn->requested_security_level = LEVEL_0;
213 #ifdef ENABLE_CLASSIC
214     conn->request_role = HCI_ROLE_INVALID;
215     conn->sniff_subrating_max_latency = 0xffff;
216     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
217     conn->link_key_type = INVALID_LINK_KEY;
218     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
219     btstack_run_loop_set_timer_context(&conn->timeout, conn);
220     hci_connection_timestamp(conn);
221 #endif
222     conn->acl_recombination_length = 0;
223     conn->acl_recombination_pos = 0;
224     conn->num_packets_sent = 0;
225 
226     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
227 #ifdef ENABLE_BLE
228     conn->le_phy_update_all_phys = 0xff;
229 #endif
230 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
231     conn->le_max_tx_octets = 27;
232 #endif
233     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
234     return conn;
235 }
236 
237 
238 /**
239  * get le connection parameter range
240 *
241  * @return le connection parameter range struct
242  */
243 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
244     *range = hci_stack->le_connection_parameter_range;
245 }
246 
247 /**
248  * set le connection parameter range
249  *
250  */
251 
252 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
253     hci_stack->le_connection_parameter_range = *range;
254 }
255 
256 /**
257  * @brief Test if connection parameters are inside in existing rage
258  * @param conn_interval_min (unit: 1.25ms)
259  * @param conn_interval_max (unit: 1.25ms)
260  * @param conn_latency
261  * @param supervision_timeout (unit: 10ms)
262  * @returns 1 if included
263  */
264 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){
265     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
266     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
267 
268     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
269     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
270 
271     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
272     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
273 
274     return 1;
275 }
276 
277 /**
278  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
279  * @note: default: 1
280  * @param max_peripheral_connections
281  */
282 #ifdef ENABLE_LE_PERIPHERAL
283 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
284     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
285 }
286 #endif
287 
288 /**
289  * get hci connections iterator
290  *
291  * @return hci connections iterator
292  */
293 
294 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
295     btstack_linked_list_iterator_init(it, &hci_stack->connections);
296 }
297 
298 /**
299  * get connection for a given handle
300  *
301  * @return connection OR NULL, if not found
302  */
303 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
304     btstack_linked_list_iterator_t it;
305     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
306     while (btstack_linked_list_iterator_has_next(&it)){
307         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
308         if ( item->con_handle == con_handle ) {
309             return item;
310         }
311     }
312     return NULL;
313 }
314 
315 /**
316  * get connection for given address
317  *
318  * @return connection OR NULL, if not found
319  */
320 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
321     btstack_linked_list_iterator_t it;
322     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
323     while (btstack_linked_list_iterator_has_next(&it)){
324         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
325         if (connection->address_type != addr_type)  continue;
326         if (memcmp(addr, connection->address, 6) != 0) continue;
327         return connection;
328     }
329     return NULL;
330 }
331 
332 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
333     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
334 }
335 
336 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
337     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
338 }
339 
340 #ifdef ENABLE_CLASSIC
341 
342 #ifdef ENABLE_SCO_OVER_HCI
343 static int hci_number_sco_connections(void){
344     int connections = 0;
345     btstack_linked_list_iterator_t it;
346     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
347     while (btstack_linked_list_iterator_has_next(&it)){
348         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
349         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
350         connections++;
351     }
352     return connections;
353 }
354 #endif
355 
356 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
357     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
358 #ifdef HAVE_EMBEDDED_TICK
359     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
360         // connections might be timed out
361         hci_emit_l2cap_check_timeout(connection);
362     }
363 #else
364     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
365         // connections might be timed out
366         hci_emit_l2cap_check_timeout(connection);
367     }
368 #endif
369 }
370 
371 static void hci_connection_timestamp(hci_connection_t *connection){
372 #ifdef HAVE_EMBEDDED_TICK
373     connection->timestamp = btstack_run_loop_embedded_get_ticks();
374 #else
375     connection->timestamp = btstack_run_loop_get_time_ms();
376 #endif
377 }
378 
379 /**
380  * add authentication flags and reset timer
381  * @note: assumes classic connection
382  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
383  */
384 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
385     bd_addr_t addr;
386     reverse_bd_addr(bd_addr, addr);
387     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
388     if (conn) {
389         connectionSetAuthenticationFlags(conn, flags);
390         hci_connection_timestamp(conn);
391     }
392 }
393 
394 static bool hci_pairing_active(hci_connection_t * hci_connection){
395     return (hci_connection->authentication_flags & PAIRING_ACTIVE_MASK) != 0;
396 }
397 
398 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
399     if (hci_pairing_active(hci_connection)) return;
400     if (ssp){
401         hci_connection->authentication_flags |= SSP_PAIRING_ACTIVE;
402     } else {
403         hci_connection->authentication_flags |= LEGACY_PAIRING_ACTIVE;
404     }
405     // if we are initiator, we have sent an HCI Authenticate Request
406     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
407 
408     log_info("pairing started, ssp %u, initiator %u", (int) ssp, (int) initiator);
409 
410     uint8_t event[12];
411     event[0] = GAP_EVENT_PAIRING_STARTED;
412     event[1] = 10;
413     reverse_bd_addr(hci_connection->address, &event[2]);
414     little_endian_store_16(event, 8, (uint16_t) hci_connection->con_handle);
415     event[10] = (uint8_t) ssp;
416     event[11] = (uint8_t) initiator;
417     hci_emit_event(event, sizeof(event), 1);
418 }
419 
420 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
421     if (!hci_pairing_active(hci_connection)) return;
422     hci_connection->authentication_flags &= ~PAIRING_ACTIVE_MASK;
423     log_info("pairing complete, status %02x", status);
424 
425     uint8_t event[12];
426     event[0] = GAP_EVENT_PAIRING_COMPLETE;
427     event[1] = 9;
428     reverse_bd_addr(hci_connection->address, &event[2]);
429     little_endian_store_16(event, 8, (uint16_t) hci_connection->con_handle);
430     event[10] = status;
431     hci_emit_event(event, sizeof(event), 1);
432 }
433 
434 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
435     hci_connection_t * conn = hci_connection_for_handle(handle);
436     if (!conn) return 0;
437     return (int) hci_pairing_active(conn);
438 }
439 
440 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
441     if (!hci_stack->link_key_db) return;
442     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
443     hci_stack->link_key_db->delete_link_key(addr);
444 }
445 
446 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
447     if (!hci_stack->link_key_db) return;
448     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
449     hci_stack->link_key_db->put_link_key(addr, link_key, type);
450 }
451 
452 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
453 	if (!hci_stack->link_key_db) return false;
454 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
455 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
456 	return result;
457 }
458 
459 void gap_delete_all_link_keys(void){
460     bd_addr_t  addr;
461     link_key_t link_key;
462     link_key_type_t type;
463     btstack_link_key_iterator_t it;
464     int ok = gap_link_key_iterator_init(&it);
465     if (!ok) {
466         log_error("could not initialize iterator");
467         return;
468     }
469     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
470         gap_drop_link_key_for_bd_addr(addr);
471     }
472     gap_link_key_iterator_done(&it);
473 }
474 
475 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
476     if (!hci_stack->link_key_db) return 0;
477     if (!hci_stack->link_key_db->iterator_init) return 0;
478     return hci_stack->link_key_db->iterator_init(it);
479 }
480 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){
481     if (!hci_stack->link_key_db) return 0;
482     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
483 }
484 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
485     if (!hci_stack->link_key_db) return;
486     hci_stack->link_key_db->iterator_done(it);
487 }
488 #endif
489 
490 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
491     switch (address_type){
492         case BD_ADDR_TYPE_LE_PUBLIC:
493         case BD_ADDR_TYPE_LE_RANDOM:
494         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
495         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
496             return true;
497         default:
498             return false;
499     }
500 }
501 
502 static int hci_is_le_connection(hci_connection_t * connection){
503     return hci_is_le_connection_type(connection->address_type);
504 }
505 
506 /**
507  * count connections
508  */
509 static int nr_hci_connections(void){
510     int count = 0;
511     btstack_linked_item_t *it;
512     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
513         count++;
514     }
515     return count;
516 }
517 
518 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
519 
520     unsigned int num_packets_sent_classic = 0;
521     unsigned int num_packets_sent_le = 0;
522 
523     btstack_linked_item_t *it;
524     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
525         hci_connection_t * connection = (hci_connection_t *) it;
526         if (hci_is_le_connection(connection)){
527             num_packets_sent_le += connection->num_packets_sent;
528         }
529         if (connection->address_type == BD_ADDR_TYPE_ACL){
530             num_packets_sent_classic += connection->num_packets_sent;
531         }
532     }
533     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
534     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
535     int free_slots_le = 0;
536 
537     if (free_slots_classic < 0){
538         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);
539         return 0;
540     }
541 
542     if (hci_stack->le_acl_packets_total_num){
543         // if we have LE slots, they are used
544         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
545         if (free_slots_le < 0){
546             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);
547             return 0;
548         }
549     } else {
550         // otherwise, classic slots are used for LE, too
551         free_slots_classic -= num_packets_sent_le;
552         if (free_slots_classic < 0){
553             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);
554             return 0;
555         }
556     }
557 
558     switch (address_type){
559         case BD_ADDR_TYPE_UNKNOWN:
560             log_error("hci_number_free_acl_slots: unknown address type");
561             return 0;
562 
563         case BD_ADDR_TYPE_ACL:
564             return free_slots_classic;
565 
566         default:
567            if (hci_stack->le_acl_packets_total_num){
568                return free_slots_le;
569            }
570            return free_slots_classic;
571     }
572 }
573 
574 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
575     // get connection type
576     hci_connection_t * connection = hci_connection_for_handle(con_handle);
577     if (!connection){
578         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
579         return 0;
580     }
581     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
582 }
583 
584 #ifdef ENABLE_CLASSIC
585 static int hci_number_free_sco_slots(void){
586     unsigned int num_sco_packets_sent  = 0;
587     btstack_linked_item_t *it;
588     if (hci_stack->synchronous_flow_control_enabled){
589         // explicit flow control
590         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
591             hci_connection_t * connection = (hci_connection_t *) it;
592             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
593             num_sco_packets_sent += connection->num_packets_sent;
594         }
595         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
596             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
597             return 0;
598         }
599         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
600     } else {
601         // implicit flow control -- TODO
602         int num_ready = 0;
603         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
604             hci_connection_t * connection = (hci_connection_t *) it;
605             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
606             if (connection->sco_tx_ready == 0) continue;
607             num_ready++;
608         }
609         return num_ready;
610     }
611 }
612 #endif
613 
614 // only used to send HCI Host Number Completed Packets
615 static int hci_can_send_comand_packet_transport(void){
616     if (hci_stack->hci_packet_buffer_reserved) return 0;
617 
618     // check for async hci transport implementations
619     if (hci_stack->hci_transport->can_send_packet_now){
620         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
621             return 0;
622         }
623     }
624     return 1;
625 }
626 
627 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
628 int hci_can_send_command_packet_now(void){
629     if (hci_can_send_comand_packet_transport() == 0) return 0;
630     return hci_stack->num_cmd_packets > 0u;
631 }
632 
633 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
634     // check for async hci transport implementations
635     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
636     return hci_stack->hci_transport->can_send_packet_now(packet_type);
637 }
638 
639 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
640     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
641     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
642 }
643 
644 int hci_can_send_acl_le_packet_now(void){
645     if (hci_stack->hci_packet_buffer_reserved) return 0;
646     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
647 }
648 
649 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
650     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
651     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
652 }
653 
654 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
655     if (hci_stack->hci_packet_buffer_reserved) return 0;
656     return hci_can_send_prepared_acl_packet_now(con_handle);
657 }
658 
659 #ifdef ENABLE_CLASSIC
660 int hci_can_send_acl_classic_packet_now(void){
661     if (hci_stack->hci_packet_buffer_reserved) return 0;
662     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
663 }
664 
665 int hci_can_send_prepared_sco_packet_now(void){
666     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
667     if (hci_have_usb_transport()){
668         return hci_stack->sco_can_send_now;
669     } else {
670         return hci_number_free_sco_slots() > 0;
671     }
672 }
673 
674 int hci_can_send_sco_packet_now(void){
675     if (hci_stack->hci_packet_buffer_reserved) return 0;
676     return hci_can_send_prepared_sco_packet_now();
677 }
678 
679 void hci_request_sco_can_send_now_event(void){
680     hci_stack->sco_waiting_for_can_send_now = 1;
681     hci_notify_if_sco_can_send_now();
682 }
683 #endif
684 
685 // used for internal checks in l2cap.c
686 int hci_is_packet_buffer_reserved(void){
687     return hci_stack->hci_packet_buffer_reserved;
688 }
689 
690 // reserves outgoing packet buffer. @returns 1 if successful
691 int hci_reserve_packet_buffer(void){
692     if (hci_stack->hci_packet_buffer_reserved) {
693         log_error("hci_reserve_packet_buffer called but buffer already reserved");
694         return 0;
695     }
696     hci_stack->hci_packet_buffer_reserved = 1;
697     return 1;
698 }
699 
700 void hci_release_packet_buffer(void){
701     hci_stack->hci_packet_buffer_reserved = 0;
702 }
703 
704 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
705 static int hci_transport_synchronous(void){
706     return hci_stack->hci_transport->can_send_packet_now == NULL;
707 }
708 
709 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
710 
711     // 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);
712 
713     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
714     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
715     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
716         max_acl_data_packet_length = hci_stack->le_data_packets_length;
717     }
718 
719 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
720     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
721         max_acl_data_packet_length = connection->le_max_tx_octets;
722     }
723 #endif
724 
725     log_debug("hci_send_acl_packet_fragments entered");
726 
727     int err;
728     // multiple packets could be send on a synchronous HCI transport
729     while (true){
730 
731         log_debug("hci_send_acl_packet_fragments loop entered");
732 
733         // get current data
734         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
735         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
736         bool more_fragments = false;
737 
738         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
739         if (current_acl_data_packet_length > max_acl_data_packet_length){
740             more_fragments = true;
741             current_acl_data_packet_length = max_acl_data_packet_length;
742         }
743 
744         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
745         if (acl_header_pos > 0u){
746             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
747             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
748             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
749         }
750 
751         // update header len
752         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
753 
754         // count packet
755         connection->num_packets_sent++;
756         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
757 
758         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
759         if (more_fragments){
760             // update start of next fragment to send
761             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
762         } else {
763             // done
764             hci_stack->acl_fragmentation_pos = 0;
765             hci_stack->acl_fragmentation_total_size = 0;
766         }
767 
768         // send packet
769         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
770         const int size = current_acl_data_packet_length + 4;
771         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
772         hci_stack->acl_fragmentation_tx_active = 1;
773         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
774 
775         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
776 
777         // done yet?
778         if (!more_fragments) break;
779 
780         // can send more?
781         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
782     }
783 
784     log_debug("hci_send_acl_packet_fragments loop over");
785 
786     // release buffer now for synchronous transport
787     if (hci_transport_synchronous()){
788         hci_stack->acl_fragmentation_tx_active = 0;
789         hci_release_packet_buffer();
790         hci_emit_transport_packet_sent();
791     }
792 
793     return err;
794 }
795 
796 // pre: caller has reserved the packet buffer
797 int hci_send_acl_packet_buffer(int size){
798 
799     // log_info("hci_send_acl_packet_buffer size %u", size);
800 
801     if (!hci_stack->hci_packet_buffer_reserved) {
802         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
803         return 0;
804     }
805 
806     uint8_t * packet = hci_stack->hci_packet_buffer;
807     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
808 
809     // check for free places on Bluetooth module
810     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
811         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
812         hci_release_packet_buffer();
813         hci_emit_transport_packet_sent();
814         return BTSTACK_ACL_BUFFERS_FULL;
815     }
816 
817     hci_connection_t *connection = hci_connection_for_handle( con_handle);
818     if (!connection) {
819         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
820         hci_release_packet_buffer();
821         hci_emit_transport_packet_sent();
822         return 0;
823     }
824 
825 #ifdef ENABLE_CLASSIC
826     hci_connection_timestamp(connection);
827 #endif
828 
829     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
830 
831     // setup data
832     hci_stack->acl_fragmentation_total_size = size;
833     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
834 
835     return hci_send_acl_packet_fragments(connection);
836 }
837 
838 #ifdef ENABLE_CLASSIC
839 // pre: caller has reserved the packet buffer
840 int hci_send_sco_packet_buffer(int size){
841 
842     // log_info("hci_send_acl_packet_buffer size %u", size);
843 
844     if (!hci_stack->hci_packet_buffer_reserved) {
845         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
846         return 0;
847     }
848 
849     uint8_t * packet = hci_stack->hci_packet_buffer;
850 
851     // skip checks in loopback mode
852     if (!hci_stack->loopback_mode){
853         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
854 
855         // check for free places on Bluetooth module
856         if (!hci_can_send_prepared_sco_packet_now()) {
857             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
858             hci_release_packet_buffer();
859             hci_emit_transport_packet_sent();
860             return BTSTACK_ACL_BUFFERS_FULL;
861         }
862 
863         // track send packet in connection struct
864         hci_connection_t *connection = hci_connection_for_handle( con_handle);
865         if (!connection) {
866             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
867             hci_release_packet_buffer();
868             hci_emit_transport_packet_sent();
869             return 0;
870         }
871 
872         if (hci_have_usb_transport()){
873             // token used
874             hci_stack->sco_can_send_now = 0;
875         } else {
876             if (hci_stack->synchronous_flow_control_enabled){
877                 connection->num_packets_sent++;
878             } else {
879                 connection->sco_tx_ready--;
880             }
881         }
882     }
883 
884     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
885 
886 #ifdef HAVE_SCO_TRANSPORT
887     hci_stack->sco_transport->send_packet(packet, size);
888     hci_release_packet_buffer();
889     hci_emit_transport_packet_sent();
890 
891     return 0;
892 #else
893     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
894     if (hci_transport_synchronous()){
895         hci_release_packet_buffer();
896         hci_emit_transport_packet_sent();
897     }
898 
899     return err;
900 #endif
901 }
902 #endif
903 
904 static void acl_handler(uint8_t *packet, uint16_t size){
905 
906     // get info
907     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
908     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
909     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
910     uint16_t acl_length         = READ_ACL_LENGTH(packet);
911 
912     // ignore non-registered handle
913     if (!conn){
914         log_error("acl_handler called with non-registered handle %u!" , con_handle);
915         return;
916     }
917 
918     // assert packet is complete
919     if ((acl_length + 4u) != size){
920         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
921         return;
922     }
923 
924 #ifdef ENABLE_CLASSIC
925     // update idle timestamp
926     hci_connection_timestamp(conn);
927 #endif
928 
929 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
930     hci_stack->host_completed_packets = 1;
931     conn->num_packets_completed++;
932 #endif
933 
934     // handle different packet types
935     switch (acl_flags & 0x03u) {
936 
937         case 0x01: // continuation fragment
938 
939             // sanity checks
940             if (conn->acl_recombination_pos == 0u) {
941                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
942                 return;
943             }
944             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
945                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
946                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
947                 conn->acl_recombination_pos = 0;
948                 return;
949             }
950 
951             // append fragment payload (header already stored)
952             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
953                          &packet[4], acl_length);
954             conn->acl_recombination_pos += acl_length;
955 
956             // forward complete L2CAP packet if complete.
957             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
958                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
959                 // reset recombination buffer
960                 conn->acl_recombination_length = 0;
961                 conn->acl_recombination_pos = 0;
962             }
963             break;
964 
965         case 0x02: { // first fragment
966 
967             // sanity check
968             if (conn->acl_recombination_pos) {
969                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
970                 conn->acl_recombination_pos = 0;
971             }
972 
973             // peek into L2CAP packet!
974             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
975 
976             // compare fragment size to L2CAP packet size
977             if (acl_length >= (l2cap_length + 4u)){
978                 // forward fragment as L2CAP packet
979                 hci_emit_acl_packet(packet, acl_length + 4u);
980             } else {
981 
982                 if (acl_length > HCI_ACL_BUFFER_SIZE){
983                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
984                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
985                     return;
986                 }
987 
988                 // store first fragment and tweak acl length for complete package
989                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
990                              packet, acl_length + 4u);
991                 conn->acl_recombination_pos    = acl_length + 4u;
992                 conn->acl_recombination_length = l2cap_length;
993                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
994             }
995             break;
996 
997         }
998         default:
999             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1000             return;
1001     }
1002 
1003     // execute main loop
1004     hci_run();
1005 }
1006 
1007 static void hci_shutdown_connection(hci_connection_t *conn){
1008     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1009 
1010 #ifdef ENABLE_CLASSIC
1011 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1012     bd_addr_type_t addr_type = conn->address_type;
1013 #endif
1014 #ifdef HAVE_SCO_TRANSPORT
1015     hci_con_handle_t con_handle = conn->con_handle;
1016 #endif
1017 #endif
1018 
1019     btstack_run_loop_remove_timer(&conn->timeout);
1020 
1021     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1022     btstack_memory_hci_connection_free( conn );
1023 
1024     // now it's gone
1025     hci_emit_nr_connections_changed();
1026 
1027 #ifdef ENABLE_CLASSIC
1028 #ifdef ENABLE_SCO_OVER_HCI
1029     // update SCO
1030     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1031         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1032     }
1033 #endif
1034 #ifdef HAVE_SCO_TRANSPORT
1035     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1036         hci_stack->sco_transport->close(con_handle);
1037     }
1038 #endif
1039 #endif
1040 }
1041 
1042 #ifdef ENABLE_CLASSIC
1043 
1044 static const uint16_t packet_type_sizes[] = {
1045     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1046     HCI_ACL_DH1_SIZE, 0, 0, 0,
1047     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1048     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1049 };
1050 static const uint8_t  packet_type_feature_requirement_bit[] = {
1051      0, // 3 slot packets
1052      1, // 5 slot packets
1053     25, // EDR 2 mpbs
1054     26, // EDR 3 mbps
1055     39, // 3 slot EDR packts
1056     40, // 5 slot EDR packet
1057 };
1058 static const uint16_t packet_type_feature_packet_mask[] = {
1059     0x0f00, // 3 slot packets
1060     0xf000, // 5 slot packets
1061     0x1102, // EDR 2 mpbs
1062     0x2204, // EDR 3 mbps
1063     0x0300, // 3 slot EDR packts
1064     0x3000, // 5 slot EDR packet
1065 };
1066 
1067 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1068     // enable packet types based on size
1069     uint16_t packet_types = 0;
1070     unsigned int i;
1071     for (i=0;i<16;i++){
1072         if (packet_type_sizes[i] == 0) continue;
1073         if (packet_type_sizes[i] <= buffer_size){
1074             packet_types |= 1 << i;
1075         }
1076     }
1077     // disable packet types due to missing local supported features
1078     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1079         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1080         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1081         if (feature_set) continue;
1082         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1083         packet_types &= ~packet_type_feature_packet_mask[i];
1084     }
1085     // flip bits for "may not be used"
1086     packet_types ^= 0x3306;
1087     return packet_types;
1088 }
1089 
1090 uint16_t hci_usable_acl_packet_types(void){
1091     return hci_stack->packet_types;
1092 }
1093 #endif
1094 
1095 uint8_t* hci_get_outgoing_packet_buffer(void){
1096     // hci packet buffer is >= acl data packet length
1097     return hci_stack->hci_packet_buffer;
1098 }
1099 
1100 uint16_t hci_max_acl_data_packet_length(void){
1101     return hci_stack->acl_data_packet_length;
1102 }
1103 
1104 #ifdef ENABLE_CLASSIC
1105 int hci_extended_sco_link_supported(void){
1106     // No. 31, byte 3, bit 7
1107     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1108 }
1109 #endif
1110 
1111 int hci_non_flushable_packet_boundary_flag_supported(void){
1112     // No. 54, byte 6, bit 6
1113     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1114 }
1115 
1116 static int gap_ssp_supported(void){
1117     // No. 51, byte 6, bit 3
1118     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1119 }
1120 
1121 static int hci_classic_supported(void){
1122 #ifdef ENABLE_CLASSIC
1123     // No. 37, byte 4, bit 5, = No BR/EDR Support
1124     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1125 #else
1126     return 0;
1127 #endif
1128 }
1129 
1130 static int hci_le_supported(void){
1131 #ifdef ENABLE_BLE
1132     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1133     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1134 #else
1135     return 0;
1136 #endif
1137 }
1138 
1139 #ifdef ENABLE_BLE
1140 
1141 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1142     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1143         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1144     } else {
1145         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1146     }
1147 }
1148 
1149 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1150     *addr_type = hci_stack->le_own_addr_type;
1151     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1152 }
1153 
1154 #ifdef ENABLE_LE_PERIPHERAL
1155 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1156     *addr_type = hci_stack->le_advertisements_own_addr_type;
1157     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1158 };
1159 #endif
1160 
1161 #ifdef ENABLE_LE_CENTRAL
1162 
1163 /**
1164  * @brief Get own addr type and address used for LE connections (Central)
1165  */
1166 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1167     *addr_type = hci_stack->le_connection_own_addr_type;
1168     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1169 }
1170 
1171 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1172 
1173     int offset = 3;
1174     int num_reports = packet[offset];
1175     offset += 1;
1176 
1177     int i;
1178     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1179     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1180     for (i=0; (i<num_reports) && (offset < size);i++){
1181         // sanity checks on data_length:
1182         uint8_t data_length = packet[offset + 8];
1183         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1184         if ((offset + 9u + data_length + 1u) > size)    return;
1185         // setup event
1186         uint8_t event_size = 10u + data_length;
1187         int pos = 0;
1188         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1189         event[pos++] = event_size;
1190         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1191         offset += 8;
1192         pos += 8;
1193         event[pos++] = packet[offset + 1 + data_length]; // rssi
1194         event[pos++] = data_length;
1195         offset++;
1196         (void)memcpy(&event[pos], &packet[offset], data_length);
1197         pos +=    data_length;
1198         offset += data_length + 1u; // rssi
1199         hci_emit_event(event, pos, 1);
1200     }
1201 }
1202 #endif
1203 #endif
1204 
1205 #ifdef ENABLE_BLE
1206 #ifdef ENABLE_LE_PERIPHERAL
1207 static void hci_update_advertisements_enabled_for_current_roles(void){
1208     if (hci_stack->le_advertisements_enabled){
1209         // get number of active le slave connections
1210         int num_slave_connections = 0;
1211         btstack_linked_list_iterator_t it;
1212         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1213         while (btstack_linked_list_iterator_has_next(&it)){
1214             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1215             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1216             if (con->state != OPEN) continue;
1217             if (con->role  != HCI_ROLE_SLAVE) continue;
1218             if (!hci_is_le_connection(con)) continue;
1219             num_slave_connections++;
1220         }
1221         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1222         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1223     } else {
1224         hci_stack->le_advertisements_enabled_for_current_roles = false;
1225     }
1226 }
1227 #endif
1228 #endif
1229 
1230 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1231 
1232 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1233     if (!hci_stack->config) return 0;
1234     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1235     // Limit baud rate for Broadcom chipsets to 3 mbps
1236     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1237         baud_rate = 3000000;
1238     }
1239     return baud_rate;
1240 }
1241 
1242 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1243     UNUSED(ds);
1244 
1245     switch (hci_stack->substate){
1246         case HCI_INIT_W4_SEND_RESET:
1247             log_info("Resend HCI Reset");
1248             hci_stack->substate = HCI_INIT_SEND_RESET;
1249             hci_stack->num_cmd_packets = 1;
1250             hci_run();
1251             break;
1252         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1253             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1254             if (hci_stack->hci_transport->reset_link){
1255                 hci_stack->hci_transport->reset_link();
1256             }
1257 
1258             /* fall through */
1259 
1260         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1261             log_info("Resend HCI Reset - CSR Warm Boot");
1262             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1263             hci_stack->num_cmd_packets = 1;
1264             hci_run();
1265             break;
1266         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1267             if (hci_stack->hci_transport->set_baudrate){
1268                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1269                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1270                 hci_stack->hci_transport->set_baudrate(baud_rate);
1271             }
1272             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1273             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1274                 if (hci_stack->hci_transport->reset_link){
1275                     log_info("Link Reset");
1276                     hci_stack->hci_transport->reset_link();
1277                 }
1278                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1279                 hci_run();
1280             }
1281             break;
1282         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1283             // otherwise continue
1284             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1285             hci_send_cmd(&hci_read_local_supported_commands);
1286             break;
1287         default:
1288             break;
1289     }
1290 }
1291 #endif
1292 
1293 static void hci_initializing_next_state(void){
1294     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1295 }
1296 
1297 // assumption: hci_can_send_command_packet_now() == true
1298 static void hci_initializing_run(void){
1299     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1300     switch (hci_stack->substate){
1301         case HCI_INIT_SEND_RESET:
1302             hci_state_reset();
1303 
1304 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1305             // prepare reset if command complete not received in 100ms
1306             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1307             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1308             btstack_run_loop_add_timer(&hci_stack->timeout);
1309 #endif
1310             // send command
1311             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1312             hci_send_cmd(&hci_reset);
1313             break;
1314         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1315             hci_send_cmd(&hci_read_local_version_information);
1316             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1317             break;
1318         case HCI_INIT_SEND_READ_LOCAL_NAME:
1319             hci_send_cmd(&hci_read_local_name);
1320             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1321             break;
1322 
1323 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1324         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1325             hci_state_reset();
1326             // prepare reset if command complete not received in 100ms
1327             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1328             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1329             btstack_run_loop_add_timer(&hci_stack->timeout);
1330             // send command
1331             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1332             hci_send_cmd(&hci_reset);
1333             break;
1334         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1335             hci_state_reset();
1336             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1337             hci_send_cmd(&hci_reset);
1338             break;
1339         case HCI_INIT_SEND_BAUD_CHANGE: {
1340             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1341             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1342             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1343             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1344             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1345             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1346             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1347             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1348                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1349                 btstack_run_loop_add_timer(&hci_stack->timeout);
1350             }
1351             break;
1352         }
1353         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1354             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1355             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1356             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1357             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1358             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1359             break;
1360         }
1361         case HCI_INIT_CUSTOM_INIT:
1362             // Custom initialization
1363             if (hci_stack->chipset && hci_stack->chipset->next_command){
1364                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1365                 bool send_cmd = false;
1366                 switch (hci_stack->chipset_result){
1367                     case BTSTACK_CHIPSET_VALID_COMMAND:
1368                         send_cmd = true;
1369                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1370                         break;
1371                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1372                         send_cmd = true;
1373                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1374                         log_info("CSR Warm Boot");
1375                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1376                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1377                         btstack_run_loop_add_timer(&hci_stack->timeout);
1378                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1379                             && hci_stack->config
1380                             && hci_stack->chipset
1381                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1382                             && hci_stack->hci_transport->set_baudrate
1383                             && hci_transport_uart_get_main_baud_rate()){
1384                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1385                         } else {
1386                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1387                         }
1388                         break;
1389                     default:
1390                         break;
1391                 }
1392 
1393                 if (send_cmd){
1394                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1395                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1396                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1397                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1398                     break;
1399                 }
1400                 log_info("Init script done");
1401 
1402                 // Init script download on Broadcom chipsets causes:
1403                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1404                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1405                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1406 
1407                     // - baud rate to reset, restore UART baud rate if needed
1408                     int need_baud_change = hci_stack->config
1409                         && hci_stack->chipset
1410                         && hci_stack->chipset->set_baudrate_command
1411                         && hci_stack->hci_transport->set_baudrate
1412                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1413                     if (need_baud_change) {
1414                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1415                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1416                         hci_stack->hci_transport->set_baudrate(baud_rate);
1417                     }
1418 
1419                     uint16_t bcm_delay_ms = 300;
1420                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1421                     //   -> Work around: wait here.
1422                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1423                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1424                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1425                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1426                     btstack_run_loop_add_timer(&hci_stack->timeout);
1427                     break;
1428                 }
1429             }
1430             // otherwise continue
1431             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1432             hci_send_cmd(&hci_read_local_supported_commands);
1433             break;
1434         case HCI_INIT_SET_BD_ADDR:
1435             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1436             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1437             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1438             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1439             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1440             break;
1441 #endif
1442 
1443         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1444             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1445             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1446             hci_send_cmd(&hci_read_local_supported_commands);
1447             break;
1448         case HCI_INIT_READ_BD_ADDR:
1449             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1450             hci_send_cmd(&hci_read_bd_addr);
1451             break;
1452         case HCI_INIT_READ_BUFFER_SIZE:
1453             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1454             hci_send_cmd(&hci_read_buffer_size);
1455             break;
1456         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1457             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1458             hci_send_cmd(&hci_read_local_supported_features);
1459             break;
1460 
1461 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1462         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1463             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1464             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1465             break;
1466         case HCI_INIT_HOST_BUFFER_SIZE:
1467             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1468             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1469                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1470             break;
1471 #endif
1472 
1473         case HCI_INIT_SET_EVENT_MASK:
1474             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1475             if (hci_le_supported()){
1476                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1477             } else {
1478                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1479                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1480             }
1481             break;
1482 
1483 #ifdef ENABLE_CLASSIC
1484         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1485             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1486             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1487             break;
1488         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1489             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1490             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1491             break;
1492         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1493             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1494             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1495             break;
1496         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1497             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1498             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1499             break;
1500         case HCI_INIT_WRITE_LOCAL_NAME: {
1501             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1502             hci_reserve_packet_buffer();
1503             uint8_t * packet = hci_stack->hci_packet_buffer;
1504             // construct HCI Command and send
1505             uint16_t opcode = hci_write_local_name.opcode;
1506             hci_stack->last_cmd_opcode = opcode;
1507             packet[0] = opcode & 0xff;
1508             packet[1] = opcode >> 8;
1509             packet[2] = DEVICE_NAME_LEN;
1510             memset(&packet[3], 0, DEVICE_NAME_LEN);
1511             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1512             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1513             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1514             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1515             // expand '00:00:00:00:00:00' in name with bd_addr
1516             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1517             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1518             break;
1519         }
1520         case HCI_INIT_WRITE_EIR_DATA: {
1521             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1522             hci_reserve_packet_buffer();
1523             uint8_t * packet = hci_stack->hci_packet_buffer;
1524             // construct HCI Command in-place and send
1525             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1526             hci_stack->last_cmd_opcode = opcode;
1527             uint16_t offset = 0;
1528             packet[offset++] = opcode & 0xff;
1529             packet[offset++] = opcode >> 8;
1530             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1531             packet[offset++] = 0;  // FEC not required
1532             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1533             if (hci_stack->eir_data){
1534                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1535                 ad_context_t context;
1536                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1537                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1538                     uint8_t size        = ad_iterator_get_data_len(&context);
1539                     const uint8_t *data = ad_iterator_get_data(&context);
1540                     // copy item
1541                     packet[offset++] = size + 1;
1542                     packet[offset++] = data_type;
1543                     memcpy(&packet[offset], data, size);
1544                     // update name item
1545                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1546                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1547                     }
1548                     offset += size;
1549                 }
1550             } else {
1551                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1552                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1553                 packet[offset++] = bytes_to_copy + 1;
1554                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1555                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1556                 // expand '00:00:00:00:00:00' in name with bd_addr
1557                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1558             }
1559             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1560             break;
1561         }
1562         case HCI_INIT_WRITE_INQUIRY_MODE:
1563             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1564             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1565             break;
1566         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1567             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1568 			hci_stack->secure_connections_active = true;
1569             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1570             break;
1571         case HCI_INIT_WRITE_SCAN_ENABLE:
1572             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1573             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1574             break;
1575         // only sent if ENABLE_SCO_OVER_HCI is defined
1576         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1577             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1578             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1579             break;
1580         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1581             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1582             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1583             break;
1584         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1585         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1586             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1587 #ifdef ENABLE_SCO_OVER_HCI
1588             log_info("BCM: Route SCO data via HCI transport");
1589             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1590 #endif
1591 #ifdef ENABLE_SCO_OVER_PCM
1592             log_info("BCM: Route SCO data via PCM interface");
1593 #ifdef ENABLE_BCM_PCM_WBS
1594             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1595             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1596 #else
1597             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1598             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1599 #endif
1600 #endif
1601             break;
1602 #ifdef ENABLE_SCO_OVER_PCM
1603         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1604             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1605             log_info("BCM: Config PCM interface for I2S");
1606 #ifdef ENABLE_BCM_PCM_WBS
1607             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1608             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1609 #else
1610             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1611             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1612 #endif
1613             break;
1614 #endif
1615 #endif
1616 
1617 #ifdef ENABLE_BLE
1618         // LE INIT
1619         case HCI_INIT_LE_READ_BUFFER_SIZE:
1620             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1621             hci_send_cmd(&hci_le_read_buffer_size);
1622             break;
1623         case HCI_INIT_LE_SET_EVENT_MASK:
1624             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1625             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1626             break;
1627         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1628             // LE Supported Host = 1, Simultaneous Host = 0
1629             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1630             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1631             break;
1632 #endif
1633 
1634 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1635         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1636             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1637             hci_send_cmd(&hci_le_read_maximum_data_length);
1638             break;
1639         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1640             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1641             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1642             break;
1643 #endif
1644 
1645 #ifdef ENABLE_LE_CENTRAL
1646         case HCI_INIT_READ_WHITE_LIST_SIZE:
1647             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1648             hci_send_cmd(&hci_le_read_white_list_size);
1649             break;
1650         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1651             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1652             hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
1653             break;
1654 #endif
1655         default:
1656             return;
1657     }
1658 }
1659 
1660 static void hci_init_done(void){
1661     // done. tell the app
1662     log_info("hci_init_done -> HCI_STATE_WORKING");
1663     hci_stack->state = HCI_STATE_WORKING;
1664     hci_emit_state();
1665     hci_run();
1666 }
1667 
1668 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1669     bool command_completed = false;
1670     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1671         uint16_t opcode = little_endian_read_16(packet,3);
1672         if (opcode == hci_stack->last_cmd_opcode){
1673             command_completed = true;
1674             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1675         } else {
1676             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1677         }
1678     }
1679 
1680     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1681         uint8_t  status = packet[2];
1682         uint16_t opcode = little_endian_read_16(packet,4);
1683         if (opcode == hci_stack->last_cmd_opcode){
1684             if (status){
1685                 command_completed = true;
1686                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1687             } else {
1688                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1689             }
1690         } else {
1691             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1692         }
1693     }
1694 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1695     // Vendor == CSR
1696     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1697         // TODO: track actual command
1698         command_completed = true;
1699     }
1700 
1701     // Vendor == Toshiba
1702     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1703         // TODO: track actual command
1704         command_completed = true;
1705         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1706         hci_stack->num_cmd_packets = 1;
1707     }
1708 #endif
1709 
1710     return command_completed;
1711 }
1712 
1713 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1714 
1715     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1716 
1717     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1718 
1719 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1720 
1721     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1722     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1723     //
1724     // HCI Reset
1725     // Timeout 100 ms
1726     // HCI Reset
1727     // Command Complete Reset
1728     // HCI Read Local Version Information
1729     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1730     // hang...
1731     //
1732     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1733     if (!command_completed
1734             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1735             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1736 
1737         uint16_t opcode = little_endian_read_16(packet,3);
1738         if (opcode == hci_reset.opcode){
1739             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1740             return;
1741         }
1742     }
1743 
1744     // CSR & H5
1745     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1746     if (!command_completed
1747             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1748             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1749 
1750         uint16_t opcode = little_endian_read_16(packet,3);
1751         if (opcode == hci_reset.opcode){
1752             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1753             return;
1754         }
1755     }
1756 
1757     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1758     // fix: Correct substate and behave as command below
1759     if (command_completed){
1760         switch (hci_stack->substate){
1761             case HCI_INIT_SEND_RESET:
1762                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1763                 break;
1764             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1765                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1766                 break;
1767             default:
1768                 break;
1769         }
1770     }
1771 
1772 #endif
1773 
1774     if (!command_completed) return;
1775 
1776     bool need_baud_change = false;
1777     bool need_addr_change = false;
1778 
1779 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1780     need_baud_change = hci_stack->config
1781                         && hci_stack->chipset
1782                         && hci_stack->chipset->set_baudrate_command
1783                         && hci_stack->hci_transport->set_baudrate
1784                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1785 
1786     need_addr_change = hci_stack->custom_bd_addr_set
1787                         && hci_stack->chipset
1788                         && hci_stack->chipset->set_bd_addr_command;
1789 #endif
1790 
1791     switch(hci_stack->substate){
1792 
1793 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1794         case HCI_INIT_SEND_RESET:
1795             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1796             // fix: just correct substate and behave as command below
1797             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1798             btstack_run_loop_remove_timer(&hci_stack->timeout);
1799             break;
1800         case HCI_INIT_W4_SEND_RESET:
1801             btstack_run_loop_remove_timer(&hci_stack->timeout);
1802             break;
1803         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1804             log_info("Received local name, need baud change %d", (int) need_baud_change);
1805             if (need_baud_change){
1806                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1807                 return;
1808             }
1809             // skip baud change
1810             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1811             return;
1812         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1813             // for STLC2500D, baud rate change already happened.
1814             // for others, baud rate gets changed now
1815             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1816                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1817                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1818                 hci_stack->hci_transport->set_baudrate(baud_rate);
1819             }
1820             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1821             return;
1822         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1823             btstack_run_loop_remove_timer(&hci_stack->timeout);
1824             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1825             return;
1826         case HCI_INIT_W4_CUSTOM_INIT:
1827             // repeat custom init
1828             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1829             return;
1830 #else
1831         case HCI_INIT_W4_SEND_RESET:
1832             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1833             return ;
1834 #endif
1835 
1836         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1837             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1838               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1839                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1840                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1841                 return;
1842             }
1843             if (need_addr_change){
1844                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1845                 return;
1846             }
1847             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1848             return;
1849 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1850         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1851             if (need_baud_change){
1852                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1853                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1854                 hci_stack->hci_transport->set_baudrate(baud_rate);
1855             }
1856             if (need_addr_change){
1857                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1858                 return;
1859             }
1860             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1861             return;
1862         case HCI_INIT_W4_SET_BD_ADDR:
1863             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1864             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1865             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1866                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1867                 return;
1868             }
1869             // skipping st warm boot
1870             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1871             return;
1872         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1873             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1874             return;
1875 #endif
1876         case HCI_INIT_W4_READ_BD_ADDR:
1877             // only read buffer size if supported
1878             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1879                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1880                 return;
1881             }
1882             // skipping read buffer size
1883             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1884             return;
1885         case HCI_INIT_W4_SET_EVENT_MASK:
1886             // skip Classic init commands for LE only chipsets
1887             if (!hci_classic_supported()){
1888 #ifdef ENABLE_BLE
1889                 if (hci_le_supported()){
1890                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1891                     return;
1892                 }
1893 #endif
1894                 log_error("Neither BR/EDR nor LE supported");
1895                 hci_init_done();
1896                 return;
1897             }
1898             if (!gap_ssp_supported()){
1899                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1900                 return;
1901             }
1902             break;
1903 #ifdef ENABLE_BLE
1904         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1905             // skip write le host if not supported (e.g. on LE only EM9301)
1906             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1907             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1908             return;
1909 
1910 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1911         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1912             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1913             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1914                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1915                 return;
1916             }
1917             // explicit fall through to reduce repetitions
1918 
1919 #ifdef ENABLE_LE_CENTRAL
1920             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1921 #else
1922             hci_init_done();
1923 #endif
1924             return;
1925 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1926 
1927 #endif  /* ENABLE_BLE */
1928 
1929         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1930             // skip write secure connections host support if not supported or disabled
1931             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1932                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1933                 return;
1934             }
1935             break;
1936 
1937 #ifdef ENABLE_SCO_OVER_HCI
1938         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1939             // skip write synchronous flow control if not supported
1940             if (hci_stack->local_supported_commands[0] & 0x04) break;
1941             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1942 
1943             /* fall through */
1944 
1945         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1946             // skip write default erroneous data reporting if not supported
1947             if (hci_stack->local_supported_commands[0] & 0x08) break;
1948             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1949 
1950             /* fall through */
1951 
1952         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1953             // skip bcm set sco pcm config on non-Broadcom chipsets
1954             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1955             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1956 
1957             /* fall through */
1958 
1959         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1960             if (!hci_le_supported()){
1961                 // SKIP LE init for Classic only configuration
1962                 hci_init_done();
1963                 return;
1964             }
1965             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1966             break;
1967 
1968 #else /* !ENABLE_SCO_OVER_HCI */
1969 
1970         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1971 #ifdef ENABLE_SCO_OVER_PCM
1972             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1973                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1974                 return;
1975             }
1976 #endif
1977             /* fall through */
1978 
1979         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1980 #ifdef ENABLE_BLE
1981             if (hci_le_supported()){
1982                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1983                 return;
1984             }
1985 #endif
1986             // SKIP LE init for Classic only configuration
1987             hci_init_done();
1988             return;
1989 #endif /* ENABLE_SCO_OVER_HCI */
1990 
1991 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1992 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1993         // Response to command before init done state -> init done
1994         case (HCI_INIT_DONE-1):
1995             hci_init_done();
1996             return;
1997 #endif
1998 
1999         default:
2000             break;
2001     }
2002     hci_initializing_next_state();
2003 }
2004 
2005 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2006     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2007     bd_addr_t bd_address;
2008     (void)memcpy(&bd_address, conn->address, 6);
2009 
2010 #ifdef ENABLE_CLASSIC
2011     // cache needed data
2012     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2013 #endif
2014 
2015     // connection failed, remove entry
2016     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2017     btstack_memory_hci_connection_free( conn );
2018 
2019 #ifdef ENABLE_CLASSIC
2020     // notify client if dedicated bonding
2021     if (notify_dedicated_bonding_failed){
2022         log_info("hci notify_dedicated_bonding_failed");
2023         hci_emit_dedicated_bonding_result(bd_address, status);
2024     }
2025 
2026     // if authentication error, also delete link key
2027     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2028         gap_drop_link_key_for_bd_addr(bd_address);
2029     }
2030 #else
2031     UNUSED(status);
2032 #endif
2033 }
2034 
2035 #ifdef ENABLE_CLASSIC
2036 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2037     // SSP Controller
2038     if (features[6] & (1 << 3)){
2039         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2040     }
2041     // eSCO
2042     if (features[3] & (1<<7)){
2043         conn->remote_supported_features[0] |= 1;
2044     }
2045     // Extended features
2046     if (features[7] & (1<<7)){
2047         conn->remote_supported_features[0] |= 2;
2048     }
2049 }
2050 
2051 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2052     // SSP Host
2053     if (features[0] & (1 << 0)){
2054         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2055     }
2056     // SC Host
2057     if (features[0] & (1 << 3)){
2058         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2059     }
2060 }
2061 
2062 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2063     // SC Controller
2064     if (features[1] & (1 << 0)){
2065         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2066     }
2067 }
2068 
2069 static void hci_handle_remote_features_received(hci_connection_t * conn){
2070     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2071     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2072     if (conn->bonding_flags & BONDING_DEDICATED){
2073         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2074     }
2075 }
2076 #endif
2077 
2078 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2079     // handle BT initialization
2080     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2081         hci_initializing_event_handler(packet, size);
2082     }
2083 
2084     // help with BT sleep
2085     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2086         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2087         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2088         hci_initializing_next_state();
2089     }
2090 }
2091 
2092 #ifdef ENABLE_CLASSIC
2093 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2094     conn->authentication_flags |= CONNECTION_ENCRYPTED;
2095     conn->encryption_key_size = encryption_key_size;
2096 
2097     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
2098         conn->requested_security_level = LEVEL_0;
2099         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2100         return;
2101     }
2102 
2103     // Request Authentication if not already done
2104     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2105     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2106 }
2107 #endif
2108 
2109 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2110     UNUSED(size);
2111 
2112     uint16_t manufacturer;
2113 #ifdef ENABLE_CLASSIC
2114     hci_con_handle_t handle;
2115     hci_connection_t * conn;
2116     uint8_t status;
2117 #endif
2118     // get num cmd packets - limit to 1 to reduce complexity
2119     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2120 
2121     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2122     switch (opcode){
2123         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2124             if (packet[5]) break;
2125             // terminate, name 248 chars
2126             packet[6+248] = 0;
2127             log_info("local name: %s", &packet[6]);
2128             break;
2129         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2130             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2131             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2132                 uint16_t acl_len = little_endian_read_16(packet, 6);
2133                 uint16_t sco_len = packet[8];
2134 
2135                 // determine usable ACL/SCO payload size
2136                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2137                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2138 
2139                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2140                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2141 
2142                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2143                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2144                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2145             }
2146             break;
2147         case HCI_OPCODE_HCI_READ_RSSI:
2148             if (packet[5] == ERROR_CODE_SUCCESS){
2149                 uint8_t event[5];
2150                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2151                 event[1] = 3;
2152                 (void)memcpy(&event[2], &packet[6], 3);
2153                 hci_emit_event(event, sizeof(event), 1);
2154             }
2155             break;
2156 #ifdef ENABLE_BLE
2157         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2158             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2159             hci_stack->le_acl_packets_total_num = packet[8];
2160             // determine usable ACL payload size
2161             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2162                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2163             }
2164             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2165             break;
2166 #endif
2167 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2168         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2169             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2170             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2171             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);
2172             break;
2173 #endif
2174 #ifdef ENABLE_LE_CENTRAL
2175         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2176             hci_stack->le_whitelist_capacity = packet[6];
2177             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2178             break;
2179 #endif
2180         case HCI_OPCODE_HCI_READ_BD_ADDR:
2181             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2182             log_info("Local Address, Status: 0x%02x: Addr: %s", packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2183 #ifdef ENABLE_CLASSIC
2184             if (hci_stack->link_key_db){
2185                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2186             }
2187 #endif
2188             break;
2189 #ifdef ENABLE_CLASSIC
2190         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2191             hci_emit_discoverable_enabled(hci_stack->discoverable);
2192             break;
2193         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2194             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2195                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2196                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2197                 hci_emit_event(event, sizeof(event), 1);
2198             }
2199             break;
2200 #endif
2201         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2202             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2203 
2204 #ifdef ENABLE_CLASSIC
2205             // determine usable ACL packet types based on host buffer size and supported features
2206             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2207             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2208 #endif
2209             // Classic/LE
2210             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2211             break;
2212         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2213             manufacturer = little_endian_read_16(packet, 10);
2214             // map Cypress to Broadcom
2215             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2216                 log_info("Treat Cypress as Broadcom");
2217                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2218                 little_endian_store_16(packet, 10, manufacturer);
2219             }
2220             hci_stack->manufacturer = manufacturer;
2221             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2222             break;
2223         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2224             hci_stack->local_supported_commands[0] =
2225                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2226                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2227                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2228                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2229                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2230                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2231                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2232                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2233             hci_stack->local_supported_commands[1] =
2234                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2235                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2236                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2237                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2238                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2239             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2240             break;
2241 #ifdef ENABLE_CLASSIC
2242         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2243             if (packet[5]) return;
2244             hci_stack->synchronous_flow_control_enabled = 1;
2245             break;
2246         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2247             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2248             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2249             conn   = hci_connection_for_handle(handle);
2250             if (conn != NULL) {
2251                 uint8_t key_size = 0;
2252                 if (status == 0){
2253                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2254                     log_info("Handle %04x key Size: %u", handle, key_size);
2255                 } else {
2256                     key_size = 1;
2257                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2258                 }
2259                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2260             }
2261             break;
2262 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2263         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2264         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2265             uint8_t event[67];
2266             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2267             event[1] = 65;
2268             (void)memset(&event[2], 0, 65);
2269             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2270                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2271                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2272                     event[2] = 3;
2273                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2274                 } else {
2275                     event[2] = 1;
2276                 }
2277             }
2278             hci_emit_event(event, sizeof(event), 0);
2279             break;
2280         }
2281 #endif
2282 #endif
2283         default:
2284             break;
2285     }
2286 }
2287 
2288 #ifdef ENABLE_BLE
2289 static void event_handle_le_connection_complete(const uint8_t * packet){
2290 	bd_addr_t addr;
2291 	bd_addr_type_t addr_type;
2292 	hci_connection_t * conn;
2293 
2294 	// Connection management
2295 	reverse_bd_addr(&packet[8], addr);
2296 	addr_type = (bd_addr_type_t)packet[7];
2297 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2298 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2299 
2300 #ifdef ENABLE_LE_CENTRAL
2301 	// handle error: error is reported only to the initiator -> outgoing connection
2302 	if (packet[3]){
2303 
2304 		// handle cancelled outgoing connection
2305 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2306 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2307 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2308 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2309 		    // reset state
2310             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2311             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2312 			// get outgoing connection conn struct for direct connect
2313 			conn = gap_get_outgoing_connection();
2314 		}
2315 
2316 		// outgoing le connection establishment is done
2317 		if (conn){
2318 			// remove entry
2319 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2320 			btstack_memory_hci_connection_free( conn );
2321 		}
2322 		return;
2323 	}
2324 #endif
2325 
2326 	// on success, both hosts receive connection complete event
2327 	if (packet[6] == HCI_ROLE_MASTER){
2328 #ifdef ENABLE_LE_CENTRAL
2329 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2330 		// note: no hci_connection_t object exists yet for connect with whitelist
2331 		if (hci_is_le_connection_type(addr_type)){
2332 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2333 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2334 		}
2335 #endif
2336 	} else {
2337 #ifdef ENABLE_LE_PERIPHERAL
2338 		// if we're slave, it was an incoming connection, advertisements have stopped
2339 		hci_stack->le_advertisements_active = false;
2340 #endif
2341 	}
2342 
2343 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2344 	if (!conn){
2345 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2346 	}
2347 
2348 	// no memory, sorry.
2349 	if (!conn){
2350 		return;
2351 	}
2352 
2353 	conn->state = OPEN;
2354 	conn->role  = packet[6];
2355 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2356 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2357 
2358 #ifdef ENABLE_LE_PERIPHERAL
2359 	if (packet[6] == HCI_ROLE_SLAVE){
2360 		hci_update_advertisements_enabled_for_current_roles();
2361 	}
2362 #endif
2363 
2364     // init unenhanced att bearer mtu
2365     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2366     conn->att_connection.mtu_exchanged = false;
2367 
2368     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2369 
2370 	// restart timer
2371 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2372 	// btstack_run_loop_add_timer(&conn->timeout);
2373 
2374 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2375 
2376 	hci_emit_nr_connections_changed();
2377 }
2378 #endif
2379 
2380 #ifdef ENABLE_CLASSIC
2381 static bool hci_ssp_security_level_possible_for_io_cap(gap_security_level_t level, uint8_t io_cap_local, uint8_t io_cap_remote){
2382     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2383     // LEVEL_4 is tested by l2cap
2384     // LEVEL 3 requires MITM protection -> check io capabilities
2385     if (level >= LEVEL_3){
2386         if (io_cap_remote  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2387         if (io_cap_local   >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2388         if ((io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY) && (io_cap_local ==  SSP_IO_CAPABILITY_KEYBOARD_ONLY)) return false;
2389     }
2390     // LEVEL 2 requires SSP, which is a given
2391     return true;
2392 }
2393 
2394 static bool hci_ssp_validate_possible_security_level(bd_addr_t addr){
2395     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2396     if (!conn) return false;
2397     // abort pairing, if requested security level cannot be met
2398     if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2399         // inlined hci_add_connection_flags_for_flipped_bd_addr
2400         hci_connection_timestamp(conn);
2401         return true;
2402     } else {
2403         log_info("Level %u cannot be reached", conn->requested_security_level);
2404         conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2405         return false;
2406     };
2407 }
2408 
2409 #endif
2410 
2411 static void event_handler(uint8_t *packet, uint16_t size){
2412 
2413     uint16_t event_length = packet[1];
2414 
2415     // assert packet is complete
2416     if (size != (event_length + 2u)){
2417         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2418         return;
2419     }
2420 
2421     bd_addr_type_t addr_type;
2422     hci_con_handle_t handle;
2423     hci_connection_t * conn;
2424     int i;
2425     int create_connection_cmd;
2426 
2427 #ifdef ENABLE_CLASSIC
2428     hci_link_type_t link_type;
2429     bd_addr_t addr;
2430 #endif
2431 
2432     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2433 
2434     switch (hci_event_packet_get_type(packet)) {
2435 
2436         case HCI_EVENT_COMMAND_COMPLETE:
2437             handle_command_complete_event(packet, size);
2438             break;
2439 
2440         case HCI_EVENT_COMMAND_STATUS:
2441             // get num cmd packets - limit to 1 to reduce complexity
2442             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2443 
2444             // check command status to detected failed outgoing connections
2445             create_connection_cmd = 0;
2446 #ifdef ENABLE_CLASSIC
2447             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2448                 create_connection_cmd = 1;
2449             }
2450 #endif
2451 #ifdef ENABLE_LE_CENTRAL
2452             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2453                 create_connection_cmd = 1;
2454             }
2455 #endif
2456             if (create_connection_cmd) {
2457                 uint8_t status = hci_event_command_status_get_status(packet);
2458                 addr_type = hci_stack->outgoing_addr_type;
2459                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2460                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), addr_type);
2461 
2462                 // reset outgoing address info
2463                 memset(hci_stack->outgoing_addr, 0, 6);
2464                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2465 
2466                 // on error
2467                 if (status != ERROR_CODE_SUCCESS){
2468 #ifdef ENABLE_LE_CENTRAL
2469                     if (hci_is_le_connection_type(addr_type)){
2470                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2471                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2472                     }
2473 #endif
2474                     // error => outgoing connection failed
2475                     if (conn != NULL){
2476                         hci_handle_connection_failed(conn, status);
2477                     }
2478                 }
2479             }
2480 
2481 #ifdef ENABLE_CLASSIC
2482             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2483                 uint8_t status = hci_event_command_status_get_status(packet);
2484                 log_info("command status (inquiry), status %x", status);
2485                 if (status == ERROR_CODE_SUCCESS) {
2486                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2487                 } else {
2488                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2489                 }
2490             }
2491 #endif
2492             break;
2493 
2494         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2495             if (size < 3) return;
2496             uint16_t num_handles = packet[2];
2497             if (size != (3u + num_handles * 4u)) return;
2498             uint16_t offset = 3;
2499             for (i=0; i<num_handles;i++){
2500                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2501                 offset += 2u;
2502                 uint16_t num_packets = little_endian_read_16(packet, offset);
2503                 offset += 2u;
2504 
2505                 conn = hci_connection_for_handle(handle);
2506                 if (!conn){
2507                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2508                     continue;
2509                 }
2510 
2511                 if (conn->num_packets_sent >= num_packets){
2512                     conn->num_packets_sent -= num_packets;
2513                 } else {
2514                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2515                     conn->num_packets_sent = 0;
2516                 }
2517                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2518 
2519 #ifdef ENABLE_CLASSIC
2520                 // For SCO, we do the can_send_now_check here
2521                 hci_notify_if_sco_can_send_now();
2522 #endif
2523             }
2524             break;
2525         }
2526 
2527 #ifdef ENABLE_CLASSIC
2528         case HCI_EVENT_INQUIRY_COMPLETE:
2529             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2530                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2531                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2532                 hci_emit_event(event, sizeof(event), 1);
2533             }
2534             break;
2535         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2536             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2537                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2538             }
2539             break;
2540         case HCI_EVENT_CONNECTION_REQUEST:
2541             reverse_bd_addr(&packet[2], addr);
2542             link_type = (hci_link_type_t) packet[11];
2543             if (hci_stack->gap_classic_accept_callback != NULL){
2544                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2545                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2546                     bd_addr_copy(hci_stack->decline_addr, addr);
2547                     break;
2548                 }
2549             }
2550 
2551             // TODO: eval COD 8-10
2552             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2553             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2554             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2555             if (!conn) {
2556                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2557             }
2558             if (!conn) {
2559                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2560                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2561                 bd_addr_copy(hci_stack->decline_addr, addr);
2562                 break;
2563             }
2564             conn->role  = HCI_ROLE_SLAVE;
2565             conn->state = RECEIVED_CONNECTION_REQUEST;
2566             // store info about eSCO
2567             if (link_type == HCI_LINK_TYPE_ESCO){
2568                 conn->remote_supported_features[0] |= 1;
2569             }
2570             hci_run();
2571             break;
2572 
2573         case HCI_EVENT_CONNECTION_COMPLETE:
2574             // Connection management
2575             reverse_bd_addr(&packet[5], addr);
2576             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2577             addr_type = BD_ADDR_TYPE_ACL;
2578             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2579             if (conn) {
2580                 if (!packet[2]){
2581                     conn->state = OPEN;
2582                     conn->con_handle = little_endian_read_16(packet, 3);
2583 
2584                     // queue get remote feature
2585                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2586 
2587                     // queue set supervision timeout if we're master
2588                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2589                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2590                     }
2591 
2592                     // restart timer
2593                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2594                     btstack_run_loop_add_timer(&conn->timeout);
2595 
2596                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2597 
2598                     hci_emit_nr_connections_changed();
2599                 } else {
2600                     // connection failed
2601                     hci_handle_connection_failed(conn, packet[2]);
2602                 }
2603             }
2604             break;
2605 
2606         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2607             reverse_bd_addr(&packet[5], addr);
2608             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2609             if (packet[2]){
2610                 // connection failed
2611                 break;
2612             }
2613             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2614             if (!conn) {
2615                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2616             }
2617             if (!conn) {
2618                 break;
2619             }
2620             conn->state = OPEN;
2621             conn->con_handle = little_endian_read_16(packet, 3);
2622 
2623 #ifdef ENABLE_SCO_OVER_HCI
2624             // update SCO
2625             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2626                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2627             }
2628             // trigger can send now
2629             if (hci_have_usb_transport()){
2630                 hci_stack->sco_can_send_now = 1;
2631             }
2632 #endif
2633 #ifdef HAVE_SCO_TRANSPORT
2634             // configure sco transport
2635             if (hci_stack->sco_transport != NULL){
2636                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2637                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2638             }
2639 #endif
2640             break;
2641 
2642         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2643             handle = little_endian_read_16(packet, 3);
2644             conn = hci_connection_for_handle(handle);
2645             if (!conn) break;
2646             if (!packet[2]){
2647                 const uint8_t * features = &packet[5];
2648                 hci_handle_remote_features_page_0(conn, features);
2649 
2650                 // read extended features if possible
2651                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2652                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2653                     break;
2654                 }
2655             }
2656             hci_handle_remote_features_received(conn);
2657             break;
2658 
2659         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2660             handle = little_endian_read_16(packet, 3);
2661             conn = hci_connection_for_handle(handle);
2662             if (!conn) break;
2663             // status = ok, page = 1
2664             if (!packet[2]) {
2665                 uint8_t page_number = packet[5];
2666                 uint8_t maximum_page_number = packet[6];
2667                 const uint8_t * features = &packet[7];
2668                 bool done = false;
2669                 switch (page_number){
2670                     case 1:
2671                         hci_handle_remote_features_page_1(conn, features);
2672                         if (maximum_page_number >= 2){
2673                             // get Secure Connections (Controller) from Page 2 if available
2674                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2675                         } else {
2676                             // otherwise, assume SC (Controller) == SC (Host)
2677                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2678                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2679                             }
2680                             done = true;
2681                         }
2682                         break;
2683                     case 2:
2684                         hci_handle_remote_features_page_2(conn, features);
2685                         done = true;
2686                         break;
2687                     default:
2688                         break;
2689                 }
2690                 if (!done) break;
2691             }
2692             hci_handle_remote_features_received(conn);
2693             break;
2694 
2695         case HCI_EVENT_LINK_KEY_REQUEST:
2696             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2697             // request handled by hci_run()
2698             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2699             break;
2700 
2701         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2702             hci_event_link_key_request_get_bd_addr(packet, addr);
2703             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2704             if (!conn) break;
2705 
2706             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2707 
2708             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2709             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2710             // Change Connection Encryption keeps link key type
2711             if (link_key_type != CHANGED_COMBINATION_KEY){
2712                 conn->link_key_type = link_key_type;
2713             }
2714             // cache link key. link keys stored in little-endian format for legacy reasons
2715             memcpy(&conn->link_key, &packet[8], 16);
2716 
2717             // only store link key:
2718             // - if bondable enabled
2719             if (hci_stack->bondable == false) break;
2720             // - if security level sufficient
2721             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2722             // - for SSP, also check if remote side requested bonding as well
2723             if (conn->link_key_type != COMBINATION_KEY){
2724                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2725                 if (!remote_bonding){
2726                     break;
2727                 }
2728             }
2729             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2730             break;
2731         }
2732 
2733         case HCI_EVENT_PIN_CODE_REQUEST:
2734             hci_event_pin_code_request_get_bd_addr(packet, addr);
2735             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2736             if (!conn) break;
2737 
2738             hci_pairing_started(conn, false);
2739             // non-bondable mode: pin code negative reply will be sent (event is not forwarded to app)
2740             if (!hci_stack->bondable){
2741                 conn->authentication_flags |= DENY_PIN_CODE_REQUEST;
2742                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2743                 hci_run();
2744                 return;
2745             }
2746             break;
2747 
2748         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2749             hci_event_io_capability_response_get_bd_addr(packet, addr);
2750             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2751             if (!conn) break;
2752 
2753             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_RESPONSE);
2754             hci_pairing_started(conn, true);
2755             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2756             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2757             break;
2758 
2759         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2760             hci_event_io_capability_response_get_bd_addr(packet, addr);
2761             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2762             if (!conn) break;
2763 
2764             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2765             hci_pairing_started(conn, true);
2766 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2767             if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2768                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2769             } else {
2770                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2771             }
2772 #endif
2773             break;
2774 
2775 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2776         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2777             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2778             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_REMOTE_OOB_DATA_REPLY);
2779             break;
2780 #endif
2781 
2782         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2783             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2784             if (hci_ssp_validate_possible_security_level(addr) == false) break;
2785             if (!hci_stack->ssp_auto_accept) break;
2786             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2787             break;
2788 
2789         case HCI_EVENT_USER_PASSKEY_REQUEST:
2790             hci_event_user_passkey_request_get_bd_addr(packet, addr);
2791             if (hci_ssp_validate_possible_security_level(addr) == false) break;
2792             if (!hci_stack->ssp_auto_accept) break;
2793             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2794             break;
2795 
2796         case HCI_EVENT_MODE_CHANGE:
2797             handle = hci_event_mode_change_get_handle(packet);
2798             conn = hci_connection_for_handle(handle);
2799             if (!conn) break;
2800             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2801             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2802             break;
2803 #endif
2804 
2805         case HCI_EVENT_ENCRYPTION_CHANGE:
2806             handle = hci_event_encryption_change_get_connection_handle(packet);
2807             conn = hci_connection_for_handle(handle);
2808             if (!conn) break;
2809             if (hci_event_encryption_change_get_status(packet) == 0u) {
2810                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2811                 if (encryption_enabled){
2812                     if (hci_is_le_connection(conn)){
2813                         // For LE, we accept connection as encrypted
2814                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2815                     }
2816 #ifdef ENABLE_CLASSIC
2817                     else {
2818 
2819                         // dedicated bonding: send result and disconnect
2820                         if (conn->bonding_flags & BONDING_DEDICATED){
2821                             conn->bonding_flags &= ~BONDING_DEDICATED;
2822                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2823                             conn->bonding_status = packet[2];
2824                             break;
2825                         }
2826 
2827                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2828                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2829                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2830                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2831                             log_info("SC during pairing, but only E0 now -> abort");
2832                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2833                             break;
2834                         }
2835 
2836                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2837                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2838                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2839                         } else {
2840                             // if not, pretend everything is perfect
2841                             hci_handle_read_encryption_key_size_complete(conn, 16);
2842                         }
2843                     }
2844 #endif
2845                 } else {
2846                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2847                 }
2848             }
2849 
2850             break;
2851 
2852 #ifdef ENABLE_CLASSIC
2853         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2854             handle = hci_event_authentication_complete_get_connection_handle(packet);
2855             conn = hci_connection_for_handle(handle);
2856             if (!conn) break;
2857 
2858             // clear authentication active flag
2859             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
2860             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
2861 
2862             // authenticated only if auth status == 0
2863             if (hci_event_authentication_complete_get_status(packet) == 0){
2864                 // authenticated
2865                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2866 
2867                 // If not already encrypted, start encryption
2868                 if ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0){
2869                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2870                     break;
2871                 }
2872             }
2873 
2874             // emit updated security level
2875             conn->requested_security_level = LEVEL_0;
2876             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2877             break;
2878 
2879         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
2880             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
2881             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2882             if (!conn) break;
2883 
2884             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
2885             break;
2886 #endif
2887 
2888         // HCI_EVENT_DISCONNECTION_COMPLETE
2889         // has been split, to first notify stack before shutting connection down
2890         // see end of function, too.
2891         case HCI_EVENT_DISCONNECTION_COMPLETE:
2892             if (packet[2]) break;   // status != 0
2893             handle = little_endian_read_16(packet, 3);
2894             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2895             if (hci_stack->acl_fragmentation_total_size > 0u) {
2896                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2897                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2898                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2899                     hci_stack->acl_fragmentation_total_size = 0;
2900                     hci_stack->acl_fragmentation_pos = 0;
2901                     if (release_buffer){
2902                         hci_release_packet_buffer();
2903                     }
2904                 }
2905             }
2906 
2907             conn = hci_connection_for_handle(handle);
2908             if (!conn) break;
2909 #ifdef ENABLE_CLASSIC
2910             // pairing failed if it was ongoing
2911             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
2912 #endif
2913             // mark connection for shutdown
2914             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2915 
2916             // emit dedicatd bonding event
2917             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2918                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2919             }
2920 
2921 #ifdef ENABLE_BLE
2922 #ifdef ENABLE_LE_PERIPHERAL
2923             // re-enable advertisements for le connections if active
2924             if (hci_is_le_connection(conn)){
2925                 hci_update_advertisements_enabled_for_current_roles();
2926             }
2927 #endif
2928 #endif
2929             break;
2930 
2931         case HCI_EVENT_HARDWARE_ERROR:
2932             log_error("Hardware Error: 0x%02x", packet[2]);
2933             if (hci_stack->hardware_error_callback){
2934                 (*hci_stack->hardware_error_callback)(packet[2]);
2935             } else {
2936                 // if no special requests, just reboot stack
2937                 hci_power_control_off();
2938                 hci_power_control_on();
2939             }
2940             break;
2941 
2942 #ifdef ENABLE_CLASSIC
2943         case HCI_EVENT_ROLE_CHANGE:
2944             if (packet[2]) break;   // status != 0
2945             reverse_bd_addr(&packet[3], addr);
2946             addr_type = BD_ADDR_TYPE_ACL;
2947             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2948             if (!conn) break;
2949             conn->role = packet[9];
2950             break;
2951 #endif
2952 
2953         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2954             // release packet buffer only for asynchronous transport and if there are not further fragements
2955             if (hci_transport_synchronous()) {
2956                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2957                 return; // instead of break: to avoid re-entering hci_run()
2958             }
2959             hci_stack->acl_fragmentation_tx_active = 0;
2960             if (hci_stack->acl_fragmentation_total_size) break;
2961             hci_release_packet_buffer();
2962 
2963             // L2CAP receives this event via the hci_emit_event below
2964 
2965 #ifdef ENABLE_CLASSIC
2966             // For SCO, we do the can_send_now_check here
2967             hci_notify_if_sco_can_send_now();
2968 #endif
2969             break;
2970 
2971 #ifdef ENABLE_CLASSIC
2972         case HCI_EVENT_SCO_CAN_SEND_NOW:
2973             // For SCO, we do the can_send_now_check here
2974             hci_stack->sco_can_send_now = 1;
2975             hci_notify_if_sco_can_send_now();
2976             return;
2977 
2978         // explode inquriy results for easier consumption
2979         case HCI_EVENT_INQUIRY_RESULT:
2980         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2981         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2982             gap_inquiry_explode(packet, size);
2983             break;
2984 #endif
2985 
2986 #ifdef ENABLE_BLE
2987         case HCI_EVENT_LE_META:
2988             switch (packet[2]){
2989 #ifdef ENABLE_LE_CENTRAL
2990                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2991                     // log_info("advertising report received");
2992                     if (!hci_stack->le_scanning_enabled) break;
2993                     le_handle_advertisement_report(packet, size);
2994                     break;
2995 #endif
2996                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2997 					event_handle_le_connection_complete(packet);
2998                     break;
2999 
3000                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3001                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3002                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3003                     conn = hci_connection_for_handle(handle);
3004                     if (!conn) break;
3005                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3006                     break;
3007 
3008                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3009                     // connection
3010                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3011                     conn = hci_connection_for_handle(handle);
3012                     if (conn) {
3013                         // read arguments
3014                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3015                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3016                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3017                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3018 
3019                         // validate against current connection parameter range
3020                         le_connection_parameter_range_t existing_range;
3021                         gap_get_connection_parameter_range(&existing_range);
3022                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3023                         if (update_parameter){
3024                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3025                             conn->le_conn_interval_min = le_conn_interval_min;
3026                             conn->le_conn_interval_max = le_conn_interval_max;
3027                             conn->le_conn_latency = le_conn_latency;
3028                             conn->le_supervision_timeout = le_supervision_timeout;
3029                         } else {
3030                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3031                         }
3032                     }
3033                     break;
3034 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3035                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3036                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3037                     conn = hci_connection_for_handle(handle);
3038                     if (conn) {
3039                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3040                     }
3041                     break;
3042 #endif
3043                 default:
3044                     break;
3045             }
3046             break;
3047 #endif
3048         case HCI_EVENT_VENDOR_SPECIFIC:
3049             // Vendor specific commands often create vendor specific event instead of num completed packets
3050             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3051             switch (hci_stack->manufacturer){
3052                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3053                     hci_stack->num_cmd_packets = 1;
3054                     break;
3055                 default:
3056                     break;
3057             }
3058             break;
3059         default:
3060             break;
3061     }
3062 
3063     handle_event_for_current_stack_state(packet, size);
3064 
3065     // notify upper stack
3066 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3067 
3068     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3069     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3070 		handle = little_endian_read_16(packet, 3);
3071 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3072 		// discard connection if app did not trigger a reconnect in the event handler
3073 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3074 			hci_shutdown_connection(aConn);
3075 		}
3076     }
3077 
3078 	// execute main loop
3079 	hci_run();
3080 }
3081 
3082 #ifdef ENABLE_CLASSIC
3083 
3084 #ifdef ENABLE_SCO_OVER_HCI
3085 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3086 static void sco_schedule_tx(hci_connection_t * conn);
3087 
3088 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3089     log_debug("SCO TX Timeout");
3090     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3091     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3092     if (!conn) return;
3093 
3094     // trigger send
3095     conn->sco_tx_ready = 1;
3096     // extra packet if CVSD but SCO buffer is too short
3097     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3098         conn->sco_tx_ready++;
3099     }
3100     hci_notify_if_sco_can_send_now();
3101 }
3102 
3103 
3104 #define SCO_TX_AFTER_RX_MS (6)
3105 
3106 static void sco_schedule_tx(hci_connection_t * conn){
3107 
3108     uint32_t now = btstack_run_loop_get_time_ms();
3109     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3110     int time_delta_ms = sco_tx_ms - now;
3111 
3112     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3113 
3114     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3115     btstack_run_loop_set_timer(timer, time_delta_ms);
3116     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3117     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3118     btstack_run_loop_add_timer(timer);
3119 }
3120 #endif
3121 
3122 static void sco_handler(uint8_t * packet, uint16_t size){
3123     // lookup connection struct
3124     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3125     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3126     if (!conn) return;
3127 
3128 #ifdef ENABLE_SCO_OVER_HCI
3129     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3130     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3131         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3132             packet[2] = 0x3c;
3133             memmove(&packet[3], &packet[23], 63);
3134             size = 63;
3135         }
3136     }
3137 
3138     if (hci_have_usb_transport()){
3139         // Nothing to do
3140     } else {
3141         // 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);
3142         if (hci_stack->synchronous_flow_control_enabled == 0){
3143             uint32_t now = btstack_run_loop_get_time_ms();
3144 
3145             if (!conn->sco_rx_valid){
3146                 // ignore first 10 packets
3147                 conn->sco_rx_count++;
3148                 // log_debug("sco rx count %u", conn->sco_rx_count);
3149                 if (conn->sco_rx_count == 10) {
3150                     // use first timestamp as is and pretent it just started
3151                     conn->sco_rx_ms = now;
3152                     conn->sco_rx_valid = 1;
3153                     conn->sco_rx_count = 0;
3154                     sco_schedule_tx(conn);
3155                 }
3156             } else {
3157                 // track expected arrival timme
3158                 conn->sco_rx_count++;
3159                 conn->sco_rx_ms += 7;
3160                 int delta = (int32_t) (now - conn->sco_rx_ms);
3161                 if (delta > 0){
3162                     conn->sco_rx_ms++;
3163                 }
3164                 // log_debug("sco rx %u", conn->sco_rx_ms);
3165                 sco_schedule_tx(conn);
3166             }
3167         }
3168     }
3169 #endif
3170 
3171     // deliver to app
3172     if (hci_stack->sco_packet_handler) {
3173         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3174     }
3175 
3176 #ifdef HAVE_SCO_TRANSPORT
3177     // We can send one packet for each received packet
3178     conn->sco_tx_ready++;
3179     hci_notify_if_sco_can_send_now();
3180 #endif
3181 
3182 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3183     conn->num_packets_completed++;
3184     hci_stack->host_completed_packets = 1;
3185     hci_run();
3186 #endif
3187 }
3188 #endif
3189 
3190 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3191     hci_dump_packet(packet_type, 1, packet, size);
3192     switch (packet_type) {
3193         case HCI_EVENT_PACKET:
3194             event_handler(packet, size);
3195             break;
3196         case HCI_ACL_DATA_PACKET:
3197             acl_handler(packet, size);
3198             break;
3199 #ifdef ENABLE_CLASSIC
3200         case HCI_SCO_DATA_PACKET:
3201             sco_handler(packet, size);
3202             break;
3203 #endif
3204         default:
3205             break;
3206     }
3207 }
3208 
3209 /**
3210  * @brief Add event packet handler.
3211  */
3212 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3213     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3214 }
3215 
3216 
3217 /** Register HCI packet handlers */
3218 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3219     hci_stack->acl_packet_handler = handler;
3220 }
3221 
3222 #ifdef ENABLE_CLASSIC
3223 /**
3224  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3225  */
3226 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3227     hci_stack->sco_packet_handler = handler;
3228 }
3229 #endif
3230 
3231 static void hci_state_reset(void){
3232     // no connections yet
3233     hci_stack->connections = NULL;
3234 
3235     // keep discoverable/connectable as this has been requested by the client(s)
3236     // hci_stack->discoverable = 0;
3237     // hci_stack->connectable = 0;
3238     // hci_stack->bondable = 1;
3239     // hci_stack->own_addr_type = 0;
3240 
3241     // buffer is free
3242     hci_stack->hci_packet_buffer_reserved = 0;
3243 
3244     // no pending cmds
3245     hci_stack->decline_reason = 0;
3246     hci_stack->new_scan_enable_value = 0xff;
3247 
3248     hci_stack->secure_connections_active = false;
3249 
3250 #ifdef ENABLE_CLASSIC
3251     hci_stack->new_page_scan_interval = 0xffff;
3252     hci_stack->new_page_scan_window = 0xffff;
3253     hci_stack->new_page_scan_type = 0xff;
3254     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3255 #endif
3256 
3257 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3258     hci_stack->classic_read_local_oob_data = true;
3259 #endif
3260 
3261     // LE
3262 #ifdef ENABLE_BLE
3263     memset(hci_stack->le_random_address, 0, 6);
3264     hci_stack->le_random_address_set = 0;
3265 #endif
3266 #ifdef ENABLE_LE_CENTRAL
3267     hci_stack->le_scanning_active  = false;
3268     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3269     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3270     hci_stack->le_whitelist_capacity = 0;
3271 #endif
3272 #ifdef ENABLE_LE_PERIPHERAL
3273     hci_stack->le_advertisements_active = false;
3274     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3275         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3276     }
3277     if (hci_stack->le_advertisements_data != NULL){
3278         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3279     }
3280 #endif
3281 }
3282 
3283 #ifdef ENABLE_CLASSIC
3284 /**
3285  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3286  */
3287 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3288     // store and open remote device db
3289     hci_stack->link_key_db = link_key_db;
3290     if (hci_stack->link_key_db) {
3291         hci_stack->link_key_db->open();
3292     }
3293 }
3294 #endif
3295 
3296 void hci_init(const hci_transport_t *transport, const void *config){
3297 
3298 #ifdef HAVE_MALLOC
3299     if (!hci_stack) {
3300         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3301     }
3302 #else
3303     hci_stack = &hci_stack_static;
3304 #endif
3305     memset(hci_stack, 0, sizeof(hci_stack_t));
3306 
3307     // reference to use transport layer implementation
3308     hci_stack->hci_transport = transport;
3309 
3310     // reference to used config
3311     hci_stack->config = config;
3312 
3313     // setup pointer for outgoing packet buffer
3314     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3315 
3316     // max acl payload size defined in config.h
3317     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3318 
3319     // register packet handlers with transport
3320     transport->register_packet_handler(&packet_handler);
3321 
3322     hci_stack->state = HCI_STATE_OFF;
3323 
3324     // class of device
3325     hci_stack->class_of_device = 0x007a020c; // Smartphone
3326 
3327     // bondable by default
3328     hci_stack->bondable = 1;
3329 
3330 #ifdef ENABLE_CLASSIC
3331     // classic name
3332     hci_stack->local_name = default_classic_name;
3333 
3334     // Master slave policy
3335     hci_stack->master_slave_policy = 1;
3336 
3337     // Allow Role Switch
3338     hci_stack->allow_role_switch = 1;
3339 
3340     // Default / minimum security level = 2
3341     hci_stack->gap_security_level = LEVEL_2;
3342 
3343     // Default Security Mode 4
3344     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3345 
3346     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3347     hci_stack->gap_required_encyrption_key_size = 7;
3348 
3349     // Link Supervision Timeout
3350     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3351 
3352 #endif
3353 
3354     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3355     hci_stack->ssp_enable = 1;
3356     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3357     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3358     hci_stack->ssp_auto_accept = 1;
3359 
3360     // Secure Connections: enable (requires support from Controller)
3361     hci_stack->secure_connections_enable = true;
3362 
3363     // voice setting - signed 16 bit pcm data with CVSD over the air
3364     hci_stack->sco_voice_setting = 0x60;
3365 
3366 #ifdef ENABLE_LE_CENTRAL
3367     // connection parameter to use for outgoing connections
3368     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3369     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3370     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3371     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3372     hci_stack->le_connection_latency      = 4;         // 4
3373     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3374     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3375     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3376 
3377     // default LE Scanning
3378     hci_stack->le_scan_type     =   0x1; // active
3379     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3380     hci_stack->le_scan_window   =  0x30; //  30 ms
3381 #endif
3382 
3383 #ifdef ENABLE_LE_PERIPHERAL
3384     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3385 #endif
3386 
3387     // connection parameter range used to answer connection parameter update requests in l2cap
3388     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3389     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3390     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3391     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3392     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3393     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3394 
3395     hci_state_reset();
3396 }
3397 
3398 void hci_deinit(void){
3399 #ifdef HAVE_MALLOC
3400     if (hci_stack) {
3401         free(hci_stack);
3402     }
3403 #endif
3404     hci_stack = NULL;
3405 
3406 #ifdef ENABLE_CLASSIC
3407     disable_l2cap_timeouts = 0;
3408 #endif
3409 }
3410 
3411 /**
3412  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3413  */
3414 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3415     hci_stack->chipset = chipset_driver;
3416 
3417     // reset chipset driver - init is also called on power_up
3418     if (hci_stack->chipset && hci_stack->chipset->init){
3419         hci_stack->chipset->init(hci_stack->config);
3420     }
3421 }
3422 
3423 /**
3424  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3425  */
3426 void hci_set_control(const btstack_control_t *hardware_control){
3427     // references to used control implementation
3428     hci_stack->control = hardware_control;
3429     // init with transport config
3430     hardware_control->init(hci_stack->config);
3431 }
3432 
3433 void hci_close(void){
3434 
3435 #ifdef ENABLE_CLASSIC
3436     // close remote device db
3437     if (hci_stack->link_key_db) {
3438         hci_stack->link_key_db->close();
3439     }
3440 #endif
3441 
3442     btstack_linked_list_iterator_t lit;
3443     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3444     while (btstack_linked_list_iterator_has_next(&lit)){
3445         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3446         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3447         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3448         hci_shutdown_connection(connection);
3449     }
3450 
3451     hci_power_control(HCI_POWER_OFF);
3452 
3453 #ifdef HAVE_MALLOC
3454     free(hci_stack);
3455 #endif
3456     hci_stack = NULL;
3457 }
3458 
3459 #ifdef HAVE_SCO_TRANSPORT
3460 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3461     hci_stack->sco_transport = sco_transport;
3462     sco_transport->register_packet_handler(&packet_handler);
3463 }
3464 #endif
3465 
3466 #ifdef ENABLE_CLASSIC
3467 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3468     // validate ranage and set
3469     if (encryption_key_size < 7)  return;
3470     if (encryption_key_size > 16) return;
3471     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3472 }
3473 
3474 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3475     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3476         hci_stack->gap_security_mode = security_mode;
3477         return ERROR_CODE_SUCCESS;
3478     } else {
3479         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3480     }
3481 }
3482 
3483 gap_security_mode_t gap_get_security_mode(void){
3484     return hci_stack->gap_security_mode;
3485 }
3486 
3487 void gap_set_security_level(gap_security_level_t security_level){
3488     hci_stack->gap_security_level = security_level;
3489 }
3490 
3491 gap_security_level_t gap_get_security_level(void){
3492     return hci_stack->gap_security_level;
3493 }
3494 
3495 void gap_set_secure_connections_only_mode(bool enable){
3496     hci_stack->gap_secure_connections_only_mode = enable;
3497 }
3498 
3499 bool gap_get_secure_connections_only_mode(void){
3500     return hci_stack->gap_secure_connections_only_mode;
3501 }
3502 #endif
3503 
3504 #ifdef ENABLE_CLASSIC
3505 void gap_set_class_of_device(uint32_t class_of_device){
3506     hci_stack->class_of_device = class_of_device;
3507 }
3508 
3509 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3510     hci_stack->default_link_policy_settings = default_link_policy_settings;
3511 }
3512 
3513 void gap_set_allow_role_switch(bool allow_role_switch){
3514     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3515 }
3516 
3517 uint8_t hci_get_allow_role_switch(void){
3518     return  hci_stack->allow_role_switch;
3519 }
3520 
3521 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3522     hci_stack->link_supervision_timeout = link_supervision_timeout;
3523 }
3524 
3525 void hci_disable_l2cap_timeout_check(void){
3526     disable_l2cap_timeouts = 1;
3527 }
3528 #endif
3529 
3530 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3531 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3532 void hci_set_bd_addr(bd_addr_t addr){
3533     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3534     hci_stack->custom_bd_addr_set = 1;
3535 }
3536 #endif
3537 
3538 // State-Module-Driver overview
3539 // state                    module  low-level
3540 // HCI_STATE_OFF             off      close
3541 // HCI_STATE_INITIALIZING,   on       open
3542 // HCI_STATE_WORKING,        on       open
3543 // HCI_STATE_HALTING,        on       open
3544 // HCI_STATE_SLEEPING,    off/sleep   close
3545 // HCI_STATE_FALLING_ASLEEP  on       open
3546 
3547 static int hci_power_control_on(void){
3548 
3549     // power on
3550     int err = 0;
3551     if (hci_stack->control && hci_stack->control->on){
3552         err = (*hci_stack->control->on)();
3553     }
3554     if (err){
3555         log_error( "POWER_ON failed");
3556         hci_emit_hci_open_failed();
3557         return err;
3558     }
3559 
3560     // int chipset driver
3561     if (hci_stack->chipset && hci_stack->chipset->init){
3562         hci_stack->chipset->init(hci_stack->config);
3563     }
3564 
3565     // init transport
3566     if (hci_stack->hci_transport->init){
3567         hci_stack->hci_transport->init(hci_stack->config);
3568     }
3569 
3570     // open transport
3571     err = hci_stack->hci_transport->open();
3572     if (err){
3573         log_error( "HCI_INIT failed, turning Bluetooth off again");
3574         if (hci_stack->control && hci_stack->control->off){
3575             (*hci_stack->control->off)();
3576         }
3577         hci_emit_hci_open_failed();
3578         return err;
3579     }
3580     return 0;
3581 }
3582 
3583 static void hci_power_control_off(void){
3584 
3585     log_info("hci_power_control_off");
3586 
3587     // close low-level device
3588     hci_stack->hci_transport->close();
3589 
3590     log_info("hci_power_control_off - hci_transport closed");
3591 
3592     // power off
3593     if (hci_stack->control && hci_stack->control->off){
3594         (*hci_stack->control->off)();
3595     }
3596 
3597     log_info("hci_power_control_off - control closed");
3598 
3599     hci_stack->state = HCI_STATE_OFF;
3600 }
3601 
3602 static void hci_power_control_sleep(void){
3603 
3604     log_info("hci_power_control_sleep");
3605 
3606 #if 0
3607     // don't close serial port during sleep
3608 
3609     // close low-level device
3610     hci_stack->hci_transport->close(hci_stack->config);
3611 #endif
3612 
3613     // sleep mode
3614     if (hci_stack->control && hci_stack->control->sleep){
3615         (*hci_stack->control->sleep)();
3616     }
3617 
3618     hci_stack->state = HCI_STATE_SLEEPING;
3619 }
3620 
3621 static int hci_power_control_wake(void){
3622 
3623     log_info("hci_power_control_wake");
3624 
3625     // wake on
3626     if (hci_stack->control && hci_stack->control->wake){
3627         (*hci_stack->control->wake)();
3628     }
3629 
3630 #if 0
3631     // open low-level device
3632     int err = hci_stack->hci_transport->open(hci_stack->config);
3633     if (err){
3634         log_error( "HCI_INIT failed, turning Bluetooth off again");
3635         if (hci_stack->control && hci_stack->control->off){
3636             (*hci_stack->control->off)();
3637         }
3638         hci_emit_hci_open_failed();
3639         return err;
3640     }
3641 #endif
3642 
3643     return 0;
3644 }
3645 
3646 static void hci_power_transition_to_initializing(void){
3647     // set up state machine
3648     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3649     hci_stack->hci_packet_buffer_reserved = 0;
3650     hci_stack->state = HCI_STATE_INITIALIZING;
3651     hci_stack->substate = HCI_INIT_SEND_RESET;
3652 }
3653 
3654 // returns error
3655 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3656     int err;
3657     switch (power_mode){
3658         case HCI_POWER_ON:
3659             err = hci_power_control_on();
3660             if (err != 0) {
3661                 log_error("hci_power_control_on() error %d", err);
3662                 return err;
3663             }
3664             hci_power_transition_to_initializing();
3665             break;
3666         case HCI_POWER_OFF:
3667             // do nothing
3668             break;
3669         case HCI_POWER_SLEEP:
3670             // do nothing (with SLEEP == OFF)
3671             break;
3672         default:
3673             btstack_assert(false);
3674             break;
3675     }
3676     return ERROR_CODE_SUCCESS;
3677 }
3678 
3679 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3680     switch (power_mode){
3681         case HCI_POWER_ON:
3682             // do nothing
3683             break;
3684         case HCI_POWER_OFF:
3685             // no connections yet, just turn it off
3686             hci_power_control_off();
3687             break;
3688         case HCI_POWER_SLEEP:
3689             // no connections yet, just turn it off
3690             hci_power_control_sleep();
3691             break;
3692         default:
3693             btstack_assert(false);
3694             break;
3695     }
3696     return ERROR_CODE_SUCCESS;
3697 }
3698 
3699 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3700     switch (power_mode){
3701         case HCI_POWER_ON:
3702             // do nothing
3703             break;
3704         case HCI_POWER_OFF:
3705             // see hci_run
3706             hci_stack->state = HCI_STATE_HALTING;
3707             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3708             break;
3709         case HCI_POWER_SLEEP:
3710             // see hci_run
3711             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3712             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3713             break;
3714         default:
3715             btstack_assert(false);
3716             break;
3717     }
3718     return ERROR_CODE_SUCCESS;
3719 }
3720 
3721 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3722     switch (power_mode){
3723         case HCI_POWER_ON:
3724             hci_power_transition_to_initializing();
3725             break;
3726         case HCI_POWER_OFF:
3727             // do nothing
3728             break;
3729         case HCI_POWER_SLEEP:
3730             // see hci_run
3731             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3732             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3733             break;
3734         default:
3735             btstack_assert(false);
3736             break;
3737     }
3738     return ERROR_CODE_SUCCESS;
3739 }
3740 
3741 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3742     switch (power_mode){
3743         case HCI_POWER_ON:
3744 
3745 #ifdef HAVE_PLATFORM_IPHONE_OS
3746             // nothing to do, if H4 supports power management
3747                     if (btstack_control_iphone_power_management_enabled()){
3748                         hci_stack->state = HCI_STATE_INITIALIZING;
3749                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3750                         break;
3751                     }
3752 #endif
3753             hci_power_transition_to_initializing();
3754             break;
3755         case HCI_POWER_OFF:
3756             // see hci_run
3757             hci_stack->state = HCI_STATE_HALTING;
3758             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3759             break;
3760         case HCI_POWER_SLEEP:
3761             // do nothing
3762             break;
3763         default:
3764             btstack_assert(false);
3765             break;
3766     }
3767     return ERROR_CODE_SUCCESS;
3768 }
3769 
3770 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3771     int err;
3772     switch (power_mode){
3773         case HCI_POWER_ON:
3774 #ifdef HAVE_PLATFORM_IPHONE_OS
3775             // nothing to do, if H4 supports power management
3776                     if (btstack_control_iphone_power_management_enabled()){
3777                         hci_stack->state = HCI_STATE_INITIALIZING;
3778                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3779                         hci_update_scan_enable();
3780                         break;
3781                     }
3782 #endif
3783             err = hci_power_control_wake();
3784             if (err) return err;
3785             hci_power_transition_to_initializing();
3786             break;
3787         case HCI_POWER_OFF:
3788             hci_stack->state = HCI_STATE_HALTING;
3789             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3790             break;
3791         case HCI_POWER_SLEEP:
3792             // do nothing
3793             break;
3794         default:
3795             btstack_assert(false);
3796             break;
3797     }
3798     return ERROR_CODE_SUCCESS;
3799 }
3800 
3801 int hci_power_control(HCI_POWER_MODE power_mode){
3802     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3803     int err = 0;
3804     switch (hci_stack->state){
3805         case HCI_STATE_OFF:
3806             err = hci_power_control_state_off(power_mode);
3807             break;
3808         case HCI_STATE_INITIALIZING:
3809             err = hci_power_control_state_initializing(power_mode);
3810             break;
3811         case HCI_STATE_WORKING:
3812             err = hci_power_control_state_working(power_mode);
3813             break;
3814         case HCI_STATE_HALTING:
3815             err = hci_power_control_state_halting(power_mode);
3816             break;
3817         case HCI_STATE_FALLING_ASLEEP:
3818             err = hci_power_control_state_falling_asleep(power_mode);
3819             break;
3820         case HCI_STATE_SLEEPING:
3821             err = hci_power_control_state_sleeping(power_mode);
3822             break;
3823         default:
3824             btstack_assert(false);
3825             break;
3826     }
3827     if (err != 0){
3828         return err;
3829     }
3830 
3831     // create internal event
3832 	hci_emit_state();
3833 
3834 	// trigger next/first action
3835 	hci_run();
3836 
3837     return 0;
3838 }
3839 
3840 
3841 #ifdef ENABLE_CLASSIC
3842 
3843 static void hci_update_scan_enable(void){
3844     // 2 = page scan, 1 = inq scan
3845     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3846     hci_run();
3847 }
3848 
3849 void gap_discoverable_control(uint8_t enable){
3850     if (enable) enable = 1; // normalize argument
3851 
3852     if (hci_stack->discoverable == enable){
3853         hci_emit_discoverable_enabled(hci_stack->discoverable);
3854         return;
3855     }
3856 
3857     hci_stack->discoverable = enable;
3858     hci_update_scan_enable();
3859 }
3860 
3861 void gap_connectable_control(uint8_t enable){
3862     if (enable) enable = 1; // normalize argument
3863 
3864     // don't emit event
3865     if (hci_stack->connectable == enable) return;
3866 
3867     hci_stack->connectable = enable;
3868     hci_update_scan_enable();
3869 }
3870 #endif
3871 
3872 void gap_local_bd_addr(bd_addr_t address_buffer){
3873     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3874 }
3875 
3876 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3877 static void hci_host_num_completed_packets(void){
3878 
3879     // create packet manually as arrays are not supported and num_commands should not get reduced
3880     hci_reserve_packet_buffer();
3881     uint8_t * packet = hci_get_outgoing_packet_buffer();
3882 
3883     uint16_t size = 0;
3884     uint16_t num_handles = 0;
3885     packet[size++] = 0x35;
3886     packet[size++] = 0x0c;
3887     size++;  // skip param len
3888     size++;  // skip num handles
3889 
3890     // add { handle, packets } entries
3891     btstack_linked_item_t * it;
3892     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3893         hci_connection_t * connection = (hci_connection_t *) it;
3894         if (connection->num_packets_completed){
3895             little_endian_store_16(packet, size, connection->con_handle);
3896             size += 2;
3897             little_endian_store_16(packet, size, connection->num_packets_completed);
3898             size += 2;
3899             //
3900             num_handles++;
3901             connection->num_packets_completed = 0;
3902         }
3903     }
3904 
3905     packet[2] = size - 3;
3906     packet[3] = num_handles;
3907 
3908     hci_stack->host_completed_packets = 0;
3909 
3910     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3911     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3912 
3913     // release packet buffer for synchronous transport implementations
3914     if (hci_transport_synchronous()){
3915         hci_release_packet_buffer();
3916         hci_emit_transport_packet_sent();
3917     }
3918 }
3919 #endif
3920 
3921 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3922     UNUSED(ds);
3923     hci_stack->substate = HCI_HALTING_CLOSE;
3924     // allow packet handlers to defer final shutdown
3925     hci_emit_state();
3926     hci_run();
3927 }
3928 
3929 static bool hci_run_acl_fragments(void){
3930     if (hci_stack->acl_fragmentation_total_size > 0u) {
3931         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3932         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3933         if (connection) {
3934             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3935                 hci_send_acl_packet_fragments(connection);
3936                 return true;
3937             }
3938         } else {
3939             // connection gone -> discard further fragments
3940             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3941             hci_stack->acl_fragmentation_total_size = 0;
3942             hci_stack->acl_fragmentation_pos = 0;
3943         }
3944     }
3945     return false;
3946 }
3947 
3948 #ifdef ENABLE_CLASSIC
3949 static bool hci_run_general_gap_classic(void){
3950 
3951     // decline incoming connections
3952     if (hci_stack->decline_reason){
3953         uint8_t reason = hci_stack->decline_reason;
3954         hci_stack->decline_reason = 0;
3955         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3956         return true;
3957     }
3958     // write page scan activity
3959     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_interval != 0xffff) && hci_classic_supported()){
3960         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
3961         hci_stack->new_page_scan_interval = 0xffff;
3962         hci_stack->new_page_scan_window = 0xffff;
3963         return true;
3964     }
3965     // write page scan type
3966     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_page_scan_type != 0xff) && hci_classic_supported()){
3967         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
3968         hci_stack->new_page_scan_type = 0xff;
3969         return true;
3970     }
3971     // send scan enable
3972     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3973         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3974         hci_stack->new_scan_enable_value = 0xff;
3975         return true;
3976     }
3977     // start/stop inquiry
3978     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3979         uint8_t duration = hci_stack->inquiry_state;
3980         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
3981         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
3982         return true;
3983     }
3984     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3985         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3986         hci_send_cmd(&hci_inquiry_cancel);
3987         return true;
3988     }
3989     // remote name request
3990     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3991         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3992         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3993                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3994         return true;
3995     }
3996 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3997     // Local OOB data
3998     if ((hci_stack->state == HCI_STATE_WORKING) && hci_stack->classic_read_local_oob_data){
3999         hci_stack->classic_read_local_oob_data = false;
4000         if (hci_stack->local_supported_commands[1] & 0x10u){
4001             hci_send_cmd(&hci_read_local_extended_oob_data);
4002         } else {
4003             hci_send_cmd(&hci_read_local_oob_data);
4004         }
4005     }
4006 #endif
4007     // pairing
4008     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4009         uint8_t state = hci_stack->gap_pairing_state;
4010         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4011         uint8_t pin_code[16];
4012         switch (state){
4013             case GAP_PAIRING_STATE_SEND_PIN:
4014                 memset(pin_code, 0, 16);
4015                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4016                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4017                 break;
4018             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4019                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4020                 break;
4021             case GAP_PAIRING_STATE_SEND_PASSKEY:
4022                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4023                 break;
4024             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4025                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4026                 break;
4027             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4028                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4029                 break;
4030             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4031                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4032                 break;
4033             default:
4034                 break;
4035         }
4036         return true;
4037     }
4038     return false;
4039 }
4040 #endif
4041 
4042 #ifdef ENABLE_BLE
4043 static bool hci_run_general_gap_le(void){
4044 
4045     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4046 
4047     if (hci_stack->state != HCI_STATE_WORKING) return false;
4048     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4049 
4050 
4051     // Phase 1: collect what to stop
4052 
4053     bool scanning_stop = false;
4054     bool connecting_stop = false;
4055     bool advertising_stop = false;
4056 
4057 #ifndef ENABLE_LE_CENTRAL
4058     UNUSED(scanning_stop);
4059     UNUSED(connecting_stop);
4060 #endif
4061 #ifndef ENABLE_LE_PERIPHERAL
4062     UNUSED(advertising_stop);
4063 #endif
4064 
4065     // check if whitelist needs modification
4066     bool whitelist_modification_pending = false;
4067     btstack_linked_list_iterator_t lit;
4068     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4069     while (btstack_linked_list_iterator_has_next(&lit)){
4070         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4071         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4072             whitelist_modification_pending = true;
4073             break;
4074         }
4075     }
4076     // check if resolving list needs modification
4077     bool resolving_list_modification_pending = false;
4078 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4079     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4080 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4081         resolving_list_modification_pending = true;
4082     }
4083 #endif
4084 
4085 #ifdef ENABLE_LE_CENTRAL
4086     // scanning control
4087     if (hci_stack->le_scanning_active) {
4088         // stop if:
4089         // - parameter change required
4090         // - it's disabled
4091         // - whitelist change required but used for scanning
4092         // - resolving list modified
4093         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4094         if ((hci_stack->le_scanning_param_update) ||
4095             !hci_stack->le_scanning_enabled ||
4096             scanning_uses_whitelist ||
4097             resolving_list_modification_pending){
4098 
4099             scanning_stop = true;
4100         }
4101     }
4102 #endif
4103 
4104 #ifdef ENABLE_LE_CENTRAL
4105     // connecting control
4106     bool connecting_with_whitelist;
4107     switch (hci_stack->le_connecting_state){
4108         case LE_CONNECTING_DIRECT:
4109         case LE_CONNECTING_WHITELIST:
4110             // stop connecting if:
4111             // - connecting uses white and whitelist modification pending
4112             // - if it got disabled
4113             // - resolving list modified
4114             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4115             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4116                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4117                 resolving_list_modification_pending) {
4118 
4119                 connecting_stop = true;
4120             }
4121             break;
4122         default:
4123             break;
4124     }
4125 #endif
4126 
4127 #ifdef ENABLE_LE_PERIPHERAL
4128     // le advertisement control
4129     if (hci_stack->le_advertisements_active){
4130         // stop if:
4131         // - parameter change required
4132         // - it's disabled
4133         // - whitelist change required but used for advertisement filter policy
4134         // - resolving list modified
4135         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4136         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4137         if (advertising_change ||
4138             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4139             (advertising_uses_whitelist & whitelist_modification_pending) ||
4140             resolving_list_modification_pending) {
4141 
4142             advertising_stop = true;
4143         }
4144     }
4145 #endif
4146 
4147 
4148     // Phase 2: stop everything that should be off during modifications
4149 
4150 #ifdef ENABLE_LE_CENTRAL
4151     if (scanning_stop){
4152         hci_stack->le_scanning_active = false;
4153         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4154         return true;
4155     }
4156 #endif
4157 
4158 #ifdef ENABLE_LE_CENTRAL
4159     if (connecting_stop){
4160         hci_send_cmd(&hci_le_create_connection_cancel);
4161         return true;
4162     }
4163 #endif
4164 
4165 #ifdef ENABLE_LE_PERIPHERAL
4166     if (advertising_stop){
4167         hci_stack->le_advertisements_active = false;
4168         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4169         return true;
4170     }
4171 #endif
4172 
4173     // Phase 3: modify
4174 
4175 #ifdef ENABLE_LE_CENTRAL
4176     if (hci_stack->le_scanning_param_update){
4177         hci_stack->le_scanning_param_update = false;
4178         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4179                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4180         return true;
4181     }
4182 #endif
4183 
4184 #ifdef ENABLE_LE_PERIPHERAL
4185     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4186         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4187         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4188         hci_send_cmd(&hci_le_set_advertising_parameters,
4189                      hci_stack->le_advertisements_interval_min,
4190                      hci_stack->le_advertisements_interval_max,
4191                      hci_stack->le_advertisements_type,
4192                      hci_stack->le_advertisements_own_addr_type,
4193                      hci_stack->le_advertisements_direct_address_type,
4194                      hci_stack->le_advertisements_direct_address,
4195                      hci_stack->le_advertisements_channel_map,
4196                      hci_stack->le_advertisements_filter_policy);
4197         return true;
4198     }
4199     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4200         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4201         uint8_t adv_data_clean[31];
4202         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4203         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4204                      hci_stack->le_advertisements_data_len);
4205         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4206         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4207         return true;
4208     }
4209     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4210         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4211         uint8_t scan_data_clean[31];
4212         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4213         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4214                      hci_stack->le_scan_response_data_len);
4215         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4216         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4217         return true;
4218     }
4219 #endif
4220 
4221 
4222 #ifdef ENABLE_LE_CENTRAL
4223     // if connect with whitelist was active and is not cancelled yet, wait until next time
4224     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4225 #endif
4226 
4227     // LE Whitelist Management
4228     if (whitelist_modification_pending){
4229         // add/remove entries
4230         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4231         while (btstack_linked_list_iterator_has_next(&lit)){
4232             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4233 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4234 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4235 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4236 				return true;
4237 			}
4238             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4239 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4240                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4241                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4242                 return true;
4243             }
4244             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4245 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4246 				btstack_memory_whitelist_entry_free(entry);
4247             }
4248         }
4249     }
4250 
4251 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4252     // LE Resolving List Management
4253     if (resolving_list_supported) {
4254 		uint16_t i;
4255 		switch (hci_stack->le_resolving_list_state) {
4256 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4257 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4258 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4259 				return true;
4260 			case LE_RESOLVING_LIST_READ_SIZE:
4261 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4262 				hci_send_cmd(&hci_le_read_resolving_list_size);
4263 				return true;
4264 			case LE_RESOLVING_LIST_SEND_CLEAR:
4265 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4266 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4267 							  sizeof(hci_stack->le_resolving_list_add_entries));
4268 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4269 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4270 				hci_send_cmd(&hci_le_clear_resolving_list);
4271 				return true;
4272 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4273 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4274 					uint8_t offset = i >> 3;
4275 					uint8_t mask = 1 << (i & 7);
4276 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4277 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4278 					bd_addr_t peer_identity_addreses;
4279 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4280 					sm_key_t peer_irk;
4281 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4282 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4283 
4284 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4285 					// trigger whitelist entry 'update' (work around for controller bug)
4286 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4287 					while (btstack_linked_list_iterator_has_next(&lit)) {
4288 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4289 						if (entry->address_type != peer_identity_addr_type) continue;
4290 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4291 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4292 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4293 					}
4294 #endif
4295 
4296 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4297 								 peer_identity_addreses);
4298 					return true;
4299 				}
4300 
4301 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4302 
4303 				/* fall through */
4304 
4305 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4306 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4307 					uint8_t offset = i >> 3;
4308 					uint8_t mask = 1 << (i & 7);
4309 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4310 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4311 					bd_addr_t peer_identity_addreses;
4312 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4313 					sm_key_t peer_irk;
4314 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4315 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4316 					const uint8_t *local_irk = gap_get_persistent_irk();
4317 					// command uses format specifier 'P' that stores 16-byte value without flip
4318 					uint8_t local_irk_flipped[16];
4319 					uint8_t peer_irk_flipped[16];
4320 					reverse_128(local_irk, local_irk_flipped);
4321 					reverse_128(peer_irk, peer_irk_flipped);
4322 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4323 								 peer_irk_flipped, local_irk_flipped);
4324 					return true;
4325 				}
4326 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4327 				break;
4328 
4329 			default:
4330 				break;
4331 		}
4332 	}
4333     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4334 #endif
4335 
4336     // Phase 4: restore state
4337 
4338 #ifdef ENABLE_LE_CENTRAL
4339     // re-start scanning
4340     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4341         hci_stack->le_scanning_active = true;
4342         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4343         return true;
4344     }
4345 #endif
4346 
4347 #ifdef ENABLE_LE_CENTRAL
4348     // re-start connecting
4349     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4350         bd_addr_t null_addr;
4351         memset(null_addr, 0, 6);
4352         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4353         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4354         hci_send_cmd(&hci_le_create_connection,
4355                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4356                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4357                      1,         // use whitelist
4358                      0,         // peer address type
4359                      null_addr, // peer bd addr
4360                      hci_stack->le_connection_own_addr_type,   // our addr type:
4361                      hci_stack->le_connection_interval_min,    // conn interval min
4362                      hci_stack->le_connection_interval_max,    // conn interval max
4363                      hci_stack->le_connection_latency,         // conn latency
4364                      hci_stack->le_supervision_timeout,        // conn latency
4365                      hci_stack->le_minimum_ce_length,          // min ce length
4366                      hci_stack->le_maximum_ce_length           // max ce length
4367         );
4368         return true;
4369     }
4370 #endif
4371 
4372 #ifdef ENABLE_LE_PERIPHERAL
4373     // re-start advertising
4374     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4375         // check if advertisements should be enabled given
4376         hci_stack->le_advertisements_active = true;
4377         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_advertisements_own_address);
4378         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4379         return true;
4380     }
4381 #endif
4382 
4383     return false;
4384 }
4385 #endif
4386 
4387 static bool hci_run_general_pending_commands(void){
4388     btstack_linked_item_t * it;
4389     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4390         hci_connection_t * connection = (hci_connection_t *) it;
4391 
4392         switch(connection->state){
4393             case SEND_CREATE_CONNECTION:
4394                 switch(connection->address_type){
4395 #ifdef ENABLE_CLASSIC
4396                     case BD_ADDR_TYPE_ACL:
4397                         log_info("sending hci_create_connection");
4398                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4399                         break;
4400 #endif
4401                     default:
4402 #ifdef ENABLE_BLE
4403 #ifdef ENABLE_LE_CENTRAL
4404                         log_info("sending hci_le_create_connection");
4405                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4406                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4407                         hci_send_cmd(&hci_le_create_connection,
4408                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4409                                      hci_stack->le_connection_scan_window,      // conn scan windows
4410                                      0,         // don't use whitelist
4411                                      connection->address_type, // peer address type
4412                                      connection->address,      // peer bd addr
4413                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4414                                      hci_stack->le_connection_interval_min,    // conn interval min
4415                                      hci_stack->le_connection_interval_max,    // conn interval max
4416                                      hci_stack->le_connection_latency,         // conn latency
4417                                      hci_stack->le_supervision_timeout,        // conn latency
4418                                      hci_stack->le_minimum_ce_length,          // min ce length
4419                                      hci_stack->le_maximum_ce_length          // max ce length
4420                         );
4421                         connection->state = SENT_CREATE_CONNECTION;
4422 #endif
4423 #endif
4424                         break;
4425                 }
4426                 return true;
4427 
4428 #ifdef ENABLE_CLASSIC
4429             case RECEIVED_CONNECTION_REQUEST:
4430                 connection->role  = HCI_ROLE_SLAVE;
4431                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4432                     log_info("sending hci_accept_connection_request");
4433                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4434                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4435                 }
4436                 return true;
4437 #endif
4438 
4439 #ifdef ENABLE_BLE
4440 #ifdef ENABLE_LE_CENTRAL
4441             case SEND_CANCEL_CONNECTION:
4442                 connection->state = SENT_CANCEL_CONNECTION;
4443                 hci_send_cmd(&hci_le_create_connection_cancel);
4444                 return true;
4445 #endif
4446 #endif
4447             case SEND_DISCONNECT:
4448                 connection->state = SENT_DISCONNECT;
4449                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4450                 return true;
4451 
4452             default:
4453                 break;
4454         }
4455 
4456         // no further commands if connection is about to get shut down
4457         if (connection->state == SENT_DISCONNECT) continue;
4458 
4459         if (connection->authentication_flags & READ_RSSI){
4460             connectionClearAuthenticationFlags(connection, READ_RSSI);
4461             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4462             return true;
4463         }
4464 
4465 #ifdef ENABLE_CLASSIC
4466 
4467         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
4468             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
4469             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4470             return true;
4471         }
4472 
4473         // Handling link key request requires remote supported features
4474         if ( ((connection->authentication_flags & HANDLE_LINK_KEY_REQUEST) != 0) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4475             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4476             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
4477 
4478             // lookup link key using cached key first
4479             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4480             if (!have_link_key && (hci_stack->link_key_db != NULL)){
4481                 have_link_key = hci_stack->link_key_db->get_link_key(connection->address, connection->link_key, &connection->link_key_type);
4482             }
4483 
4484             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
4485             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
4486             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(connection->link_key_type) == 1) && !sc_enabled_remote;
4487             if (sc_downgrade){
4488                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
4489                 connection->state = SENT_DISCONNECT;
4490                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4491                 return true;
4492             }
4493 
4494             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4495             if (have_link_key && security_level_sufficient){
4496                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4497             } else {
4498                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4499             }
4500             return true;
4501         }
4502 
4503         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
4504             log_info("denying to pin request");
4505             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
4506             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4507             return true;
4508         }
4509 
4510         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
4511             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
4512             // set authentication requirements:
4513             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4514             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4515             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4516             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4517                 authreq |= 1;
4518             }
4519             bool bonding = hci_stack->bondable;
4520             if (connection->authentication_flags & RECV_IO_CAPABILITIES_RESPONSE){
4521                 // if we have received IO Cap Response, we're in responder role
4522                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4523                 if (bonding && !remote_bonding){
4524                     log_info("Remote not bonding, dropping local flag");
4525                     bonding = false;
4526                 }
4527             }
4528             if (bonding){
4529                 if (connection->bonding_flags & BONDING_DEDICATED){
4530                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4531                 } else {
4532                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4533                 }
4534             }
4535             uint8_t have_oob_data = 0;
4536 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4537             if (connection->classic_oob_c_192 != NULL){
4538                     have_oob_data |= 1;
4539             }
4540             if (connection->classic_oob_c_256 != NULL){
4541                 have_oob_data |= 2;
4542             }
4543 #endif
4544             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4545             return true;
4546         }
4547 
4548         if (connection->authentication_flags & SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4549             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4550             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4551             return true;
4552         }
4553 
4554 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4555         if (connection->authentication_flags & SEND_REMOTE_OOB_DATA_REPLY){
4556             connectionClearAuthenticationFlags(connection, SEND_REMOTE_OOB_DATA_REPLY);
4557             const uint8_t zero[16] = { 0 };
4558             const uint8_t * r_192 = zero;
4559             const uint8_t * c_192 = zero;
4560             const uint8_t * r_256 = zero;
4561             const uint8_t * c_256 = zero;
4562             // verify P-256 OOB
4563             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4564                 c_256 = connection->classic_oob_c_256;
4565                 if (connection->classic_oob_r_256 != NULL) {
4566                     r_256 = connection->classic_oob_r_256;
4567                 }
4568             }
4569             // verify P-192 OOB
4570             if ((connection->classic_oob_c_192 != NULL)) {
4571                 c_192 = connection->classic_oob_c_192;
4572                 if (connection->classic_oob_r_192 != NULL) {
4573                     r_192 = connection->classic_oob_r_192;
4574                 }
4575             }
4576             // Reply
4577             if (c_256 != zero) {
4578                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4579             } else if (c_192 != zero){
4580                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4581             } else {
4582                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4583             }
4584             return true;
4585         }
4586 #endif
4587 
4588         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
4589             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
4590             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4591             return true;
4592         }
4593 
4594         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
4595             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
4596             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4597             return true;
4598         }
4599 
4600         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4601             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4602             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4603             return true;
4604         }
4605 
4606         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4607             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4608             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4609             return true;
4610         }
4611 
4612         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4613             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4614             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4615             return true;
4616         }
4617 
4618         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4619             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4620             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4621             connection->state = SENT_DISCONNECT;
4622             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4623             return true;
4624         }
4625 
4626         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
4627             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4628             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4629             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4630             return true;
4631         }
4632 
4633         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4634             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4635             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4636             return true;
4637         }
4638         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4639             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4640             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4641             return true;
4642         }
4643 #endif
4644 
4645         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4646             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4647 #ifdef ENABLE_CLASSIC
4648             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4649 #endif
4650             if (connection->state != SENT_DISCONNECT){
4651                 connection->state = SENT_DISCONNECT;
4652                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4653                 return true;
4654             }
4655         }
4656 
4657 #ifdef ENABLE_CLASSIC
4658         uint16_t sniff_min_interval;
4659         switch (connection->sniff_min_interval){
4660             case 0:
4661                 break;
4662             case 0xffff:
4663                 connection->sniff_min_interval = 0;
4664                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4665                 return true;
4666             default:
4667                 sniff_min_interval = connection->sniff_min_interval;
4668                 connection->sniff_min_interval = 0;
4669                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4670                 return true;
4671         }
4672 
4673         if (connection->sniff_subrating_max_latency != 0xffff){
4674             uint16_t max_latency = connection->sniff_subrating_max_latency;
4675             connection->sniff_subrating_max_latency = 0;
4676             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4677             return true;
4678         }
4679 
4680         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4681             uint8_t service_type = (uint8_t) connection->qos_service_type;
4682             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4683             hci_send_cmd(&hci_qos_setup, connection->con_handle, 0, service_type, connection->qos_token_rate, connection->qos_peak_bandwidth, connection->qos_latency, connection->qos_delay_variation);
4684             return true;
4685         }
4686 
4687         if (connection->request_role != HCI_ROLE_INVALID){
4688             hci_role_t role = connection->request_role;
4689             connection->request_role = HCI_ROLE_INVALID;
4690             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4691             return true;
4692         }
4693 #endif
4694 
4695 #ifdef ENABLE_BLE
4696         switch (connection->le_con_parameter_update_state){
4697             // response to L2CAP CON PARAMETER UPDATE REQUEST
4698             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4699                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4700                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4701                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4702                              0x0000, 0xffff);
4703                 return true;
4704             case CON_PARAMETER_UPDATE_REPLY:
4705                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4706                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4707                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4708                              0x0000, 0xffff);
4709                 return true;
4710             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4711                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4712                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4713                 return true;
4714             default:
4715                 break;
4716         }
4717         if (connection->le_phy_update_all_phys != 0xffu){
4718             uint8_t all_phys = connection->le_phy_update_all_phys;
4719             connection->le_phy_update_all_phys = 0xff;
4720             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);
4721             return true;
4722         }
4723 #endif
4724     }
4725     return false;
4726 }
4727 
4728 static void hci_run(void){
4729 
4730     bool done;
4731 
4732     // send continuation fragments first, as they block the prepared packet buffer
4733     done = hci_run_acl_fragments();
4734     if (done) return;
4735 
4736 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4737     // send host num completed packets next as they don't require num_cmd_packets > 0
4738     if (!hci_can_send_comand_packet_transport()) return;
4739     if (hci_stack->host_completed_packets){
4740         hci_host_num_completed_packets();
4741         return;
4742     }
4743 #endif
4744 
4745     if (!hci_can_send_command_packet_now()) return;
4746 
4747     // global/non-connection oriented commands
4748 
4749 
4750 #ifdef ENABLE_CLASSIC
4751     // general gap classic
4752     done = hci_run_general_gap_classic();
4753     if (done) return;
4754 #endif
4755 
4756 #ifdef ENABLE_BLE
4757     // general gap le
4758     done = hci_run_general_gap_le();
4759     if (done) return;
4760 #endif
4761 
4762     // send pending HCI commands
4763     done = hci_run_general_pending_commands();
4764     if (done) return;
4765 
4766     // stack state sub statemachines
4767     hci_connection_t * connection;
4768     switch (hci_stack->state){
4769         case HCI_STATE_INITIALIZING:
4770             hci_initializing_run();
4771             break;
4772 
4773         case HCI_STATE_HALTING:
4774 
4775             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4776             switch (hci_stack->substate){
4777                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4778                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4779 
4780 #ifdef ENABLE_BLE
4781 #ifdef ENABLE_LE_CENTRAL
4782                     // free whitelist entries
4783                     {
4784                         btstack_linked_list_iterator_t lit;
4785                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4786                         while (btstack_linked_list_iterator_has_next(&lit)){
4787                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4788                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4789                             btstack_memory_whitelist_entry_free(entry);
4790                         }
4791                     }
4792 #endif
4793 #endif
4794                     // close all open connections
4795                     connection =  (hci_connection_t *) hci_stack->connections;
4796                     if (connection){
4797                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4798                         if (!hci_can_send_command_packet_now()) return;
4799 
4800                         // check state
4801                         if (connection->state == SENT_DISCONNECT) return;
4802                         connection->state = SENT_DISCONNECT;
4803 
4804                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4805 
4806                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4807                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4808 
4809                         // ... which would be ignored anyway as we shutdown (free) the connection now
4810                         hci_shutdown_connection(connection);
4811 
4812                         // finally, send the disconnect command
4813                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4814                         return;
4815                     }
4816 
4817                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4818                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4819                         log_info("HCI_STATE_HALTING: wait 50 ms");
4820                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4821                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4822                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4823                         btstack_run_loop_add_timer(&hci_stack->timeout);
4824                         break;
4825                     }
4826 
4827                     /* fall through */
4828 
4829                 case HCI_HALTING_CLOSE:
4830                     log_info("HCI_STATE_HALTING, calling off");
4831 
4832                     // switch mode
4833                     hci_power_control_off();
4834 
4835                     log_info("HCI_STATE_HALTING, emitting state");
4836                     hci_emit_state();
4837                     log_info("HCI_STATE_HALTING, done");
4838                     break;
4839 
4840                 case HCI_HALTING_W4_TIMER:
4841                     // keep waiting
4842 
4843                     break;
4844                 default:
4845                     break;
4846             }
4847 
4848             break;
4849 
4850         case HCI_STATE_FALLING_ASLEEP:
4851             switch(hci_stack->substate) {
4852                 case HCI_FALLING_ASLEEP_DISCONNECT:
4853                     log_info("HCI_STATE_FALLING_ASLEEP");
4854                     // close all open connections
4855                     connection =  (hci_connection_t *) hci_stack->connections;
4856 
4857 #ifdef HAVE_PLATFORM_IPHONE_OS
4858                     // don't close connections, if H4 supports power management
4859                     if (btstack_control_iphone_power_management_enabled()){
4860                         connection = NULL;
4861                     }
4862 #endif
4863                     if (connection){
4864 
4865                         // send disconnect
4866                         if (!hci_can_send_command_packet_now()) return;
4867 
4868                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4869                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4870 
4871                         // send disconnected event right away - causes higher layer connections to get closed, too.
4872                         hci_shutdown_connection(connection);
4873                         return;
4874                     }
4875 
4876                     if (hci_classic_supported()){
4877                         // disable page and inquiry scan
4878                         if (!hci_can_send_command_packet_now()) return;
4879 
4880                         log_info("HCI_STATE_HALTING, disabling inq scans");
4881                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4882 
4883                         // continue in next sub state
4884                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4885                         break;
4886                     }
4887 
4888                     /* fall through */
4889 
4890                 case HCI_FALLING_ASLEEP_COMPLETE:
4891                     log_info("HCI_STATE_HALTING, calling sleep");
4892 #ifdef HAVE_PLATFORM_IPHONE_OS
4893                     // don't actually go to sleep, if H4 supports power management
4894                     if (btstack_control_iphone_power_management_enabled()){
4895                         // SLEEP MODE reached
4896                         hci_stack->state = HCI_STATE_SLEEPING;
4897                         hci_emit_state();
4898                         break;
4899                     }
4900 #endif
4901                     // switch mode
4902                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4903                     hci_emit_state();
4904                     break;
4905 
4906                 default:
4907                     break;
4908             }
4909             break;
4910 
4911         default:
4912             break;
4913     }
4914 }
4915 
4916 int hci_send_cmd_packet(uint8_t *packet, int size){
4917     // house-keeping
4918 
4919 #ifdef ENABLE_CLASSIC
4920     bd_addr_t addr;
4921     hci_connection_t * conn;
4922 #endif
4923 #ifdef ENABLE_LE_CENTRAL
4924     uint8_t initiator_filter_policy;
4925 #endif
4926 
4927     uint16_t opcode = little_endian_read_16(packet, 0);
4928     switch (opcode) {
4929         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4930             hci_stack->loopback_mode = packet[3];
4931             break;
4932 
4933 #ifdef ENABLE_CLASSIC
4934         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4935             reverse_bd_addr(&packet[3], addr);
4936             log_info("Create_connection to %s", bd_addr_to_str(addr));
4937 
4938             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4939             if (!conn) {
4940                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4941                 if (!conn) {
4942                     // notify client that alloc failed
4943                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4944                     return -1; // packet not sent to controller
4945                 }
4946                 conn->state = SEND_CREATE_CONNECTION;
4947                 conn->role  = HCI_ROLE_MASTER;
4948             }
4949             log_info("conn state %u", conn->state);
4950             switch (conn->state) {
4951                 // if connection active exists
4952                 case OPEN:
4953                     // and OPEN, emit connection complete command
4954                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4955                     return -1; // packet not sent to controller
4956                 case RECEIVED_DISCONNECTION_COMPLETE:
4957                     // create connection triggered in disconnect complete event, let's do it now
4958                     break;
4959                 case SEND_CREATE_CONNECTION:
4960                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4961                     break;
4962                 default:
4963                     // otherwise, just ignore as it is already in the open process
4964                     return -1; // packet not sent to controller
4965             }
4966             conn->state = SENT_CREATE_CONNECTION;
4967 
4968             // track outgoing connection
4969             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4970             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4971             break;
4972         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4973             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4974             break;
4975         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4976             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4977             break;
4978         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4979             if (hci_stack->link_key_db) {
4980                 reverse_bd_addr(&packet[3], addr);
4981                 hci_stack->link_key_db->delete_link_key(addr);
4982             }
4983             break;
4984 
4985 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
4986         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4987             // setup_synchronous_connection? Voice setting at offset 22
4988             // TODO: compare to current setting if sco connection already active
4989             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4990             break;
4991         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4992             // accept_synchronus_connection? Voice setting at offset 18
4993             // TODO: compare to current setting if sco connection already active
4994             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4995             break;
4996 #endif
4997 #endif
4998 
4999 #ifdef ENABLE_BLE
5000         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5001             hci_stack->le_random_address_set = 1;
5002             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5003             break;
5004 #ifdef ENABLE_LE_PERIPHERAL
5005         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5006             hci_stack->le_advertisements_active = packet[3] != 0;
5007             break;
5008 #endif
5009 #ifdef ENABLE_LE_CENTRAL
5010         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5011             // white list used?
5012             initiator_filter_policy = packet[7];
5013             switch (initiator_filter_policy) {
5014                 case 0:
5015                     // whitelist not used
5016                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5017                     break;
5018                 case 1:
5019                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5020                     break;
5021                 default:
5022                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5023                     break;
5024             }
5025             // track outgoing connection
5026             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5027             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5028             break;
5029         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5030             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5031             break;
5032 #endif
5033 #endif
5034         default:
5035             break;
5036     }
5037 
5038     hci_stack->num_cmd_packets--;
5039 
5040     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5041     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5042 }
5043 
5044 // disconnect because of security block
5045 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5046     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5047     if (!connection) return;
5048     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5049 }
5050 
5051 
5052 // Configure Secure Simple Pairing
5053 
5054 #ifdef ENABLE_CLASSIC
5055 
5056 // enable will enable SSP during init
5057 void gap_ssp_set_enable(int enable){
5058     hci_stack->ssp_enable = enable;
5059 }
5060 
5061 static int hci_local_ssp_activated(void){
5062     return gap_ssp_supported() && hci_stack->ssp_enable;
5063 }
5064 
5065 // if set, BTstack will respond to io capability request using authentication requirement
5066 void gap_ssp_set_io_capability(int io_capability){
5067     hci_stack->ssp_io_capability = io_capability;
5068 }
5069 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5070     hci_stack->ssp_authentication_requirement = authentication_requirement;
5071 }
5072 
5073 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5074 void gap_ssp_set_auto_accept(int auto_accept){
5075     hci_stack->ssp_auto_accept = auto_accept;
5076 }
5077 
5078 void gap_secure_connections_enable(bool enable){
5079     hci_stack->secure_connections_enable = enable;
5080 }
5081 
5082 #endif
5083 
5084 // va_list part of hci_send_cmd
5085 int hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5086     if (!hci_can_send_command_packet_now()){
5087         log_error("hci_send_cmd called but cannot send packet now");
5088         return 0;
5089     }
5090 
5091     // for HCI INITIALIZATION
5092     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5093     hci_stack->last_cmd_opcode = cmd->opcode;
5094 
5095     hci_reserve_packet_buffer();
5096     uint8_t * packet = hci_stack->hci_packet_buffer;
5097     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5098     int err = hci_send_cmd_packet(packet, size);
5099 
5100     // release packet buffer on error or for synchronous transport implementations
5101     if ((err < 0) || hci_transport_synchronous()){
5102         hci_release_packet_buffer();
5103         hci_emit_transport_packet_sent();
5104     }
5105 
5106     return err;
5107 }
5108 
5109 /**
5110  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5111  */
5112 int hci_send_cmd(const hci_cmd_t * cmd, ...){
5113     va_list argptr;
5114     va_start(argptr, cmd);
5115     int res = hci_send_cmd_va_arg(cmd, argptr);
5116     va_end(argptr);
5117     return res;
5118 }
5119 
5120 // Create various non-HCI events.
5121 // TODO: generalize, use table similar to hci_create_command
5122 
5123 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5124     // dump packet
5125     if (dump) {
5126         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5127     }
5128 
5129     // dispatch to all event handlers
5130     btstack_linked_list_iterator_t it;
5131     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5132     while (btstack_linked_list_iterator_has_next(&it)){
5133         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5134         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5135     }
5136 }
5137 
5138 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5139     if (!hci_stack->acl_packet_handler) return;
5140     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5141 }
5142 
5143 #ifdef ENABLE_CLASSIC
5144 static void hci_notify_if_sco_can_send_now(void){
5145     // notify SCO sender if waiting
5146     if (!hci_stack->sco_waiting_for_can_send_now) return;
5147     if (hci_can_send_sco_packet_now()){
5148         hci_stack->sco_waiting_for_can_send_now = 0;
5149         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5150         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5151         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5152     }
5153 }
5154 
5155 // parsing end emitting has been merged to reduce code size
5156 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5157     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5158 
5159     uint8_t * eir_data;
5160     ad_context_t context;
5161     const uint8_t * name;
5162     uint8_t         name_len;
5163 
5164     if (size < 3) return;
5165 
5166     int event_type = hci_event_packet_get_type(packet);
5167     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5168     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5169 
5170     switch (event_type){
5171         case HCI_EVENT_INQUIRY_RESULT:
5172         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5173             if (size != (3 + (num_responses * 14))) return;
5174             break;
5175         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5176             if (size != 257) return;
5177             if (num_responses != 1) return;
5178             break;
5179         default:
5180             return;
5181     }
5182 
5183     // event[1] is set at the end
5184     int i;
5185     for (i=0; i<num_responses;i++){
5186         memset(event, 0, sizeof(event));
5187         event[0] = GAP_EVENT_INQUIRY_RESULT;
5188         uint8_t event_size = 18;    // if name is not set by EIR
5189 
5190         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5191         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5192         (void)memcpy(&event[9],
5193                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5194                      3); // class of device
5195         (void)memcpy(&event[12],
5196                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5197                      2); // clock offset
5198 
5199         switch (event_type){
5200             case HCI_EVENT_INQUIRY_RESULT:
5201                 // 14,15,16,17 = 0, size 18
5202                 break;
5203             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5204                 event[14] = 1;
5205                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5206                 // 16,17 = 0, size 18
5207                 break;
5208             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5209                 event[14] = 1;
5210                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5211                 // EIR packets only contain a single inquiry response
5212                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5213                 name = NULL;
5214                 // Iterate over EIR data
5215                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5216                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5217                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5218                     const uint8_t * data = ad_iterator_get_data(&context);
5219                     // Prefer Complete Local Name over Shortened Local Name
5220                     switch (data_type){
5221                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5222                             if (name) continue;
5223                             /* fall through */
5224                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5225                             name = data;
5226                             name_len = data_size;
5227                             break;
5228                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5229                             if (data_size != 8) break;
5230                             event[16] = 1;
5231                             memcpy(&event[17], data, 8);
5232                             break;
5233                         default:
5234                             break;
5235                     }
5236                 }
5237                 if (name){
5238                     event[25] = 1;
5239                     // truncate name if needed
5240                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5241                     event[26] = len;
5242                     (void)memcpy(&event[27], name, len);
5243                     event_size += len;
5244                 }
5245                 break;
5246             default:
5247                 return;
5248         }
5249         event[1] = event_size - 2;
5250         hci_emit_event(event, event_size, 1);
5251     }
5252 }
5253 #endif
5254 
5255 void hci_emit_state(void){
5256     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5257     uint8_t event[3];
5258     event[0] = BTSTACK_EVENT_STATE;
5259     event[1] = sizeof(event) - 2u;
5260     event[2] = hci_stack->state;
5261     hci_emit_event(event, sizeof(event), 1);
5262 }
5263 
5264 #ifdef ENABLE_CLASSIC
5265 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5266     uint8_t event[13];
5267     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5268     event[1] = sizeof(event) - 2;
5269     event[2] = status;
5270     little_endian_store_16(event, 3, con_handle);
5271     reverse_bd_addr(address, &event[5]);
5272     event[11] = 1; // ACL connection
5273     event[12] = 0; // encryption disabled
5274     hci_emit_event(event, sizeof(event), 1);
5275 }
5276 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5277     if (disable_l2cap_timeouts) return;
5278     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5279     uint8_t event[4];
5280     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5281     event[1] = sizeof(event) - 2;
5282     little_endian_store_16(event, 2, conn->con_handle);
5283     hci_emit_event(event, sizeof(event), 1);
5284 }
5285 #endif
5286 
5287 #ifdef ENABLE_BLE
5288 #ifdef ENABLE_LE_CENTRAL
5289 static void hci_emit_le_connection_complete(uint8_t address_type, const bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5290     uint8_t event[21];
5291     event[0] = HCI_EVENT_LE_META;
5292     event[1] = sizeof(event) - 2u;
5293     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5294     event[3] = status;
5295     little_endian_store_16(event, 4, con_handle);
5296     event[6] = 0; // TODO: role
5297     event[7] = address_type;
5298     reverse_bd_addr(address, &event[8]);
5299     little_endian_store_16(event, 14, 0); // interval
5300     little_endian_store_16(event, 16, 0); // latency
5301     little_endian_store_16(event, 18, 0); // supervision timeout
5302     event[20] = 0; // master clock accuracy
5303     hci_emit_event(event, sizeof(event), 1);
5304 }
5305 #endif
5306 #endif
5307 
5308 static void hci_emit_transport_packet_sent(void){
5309     // notify upper stack that it might be possible to send again
5310     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5311     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5312 }
5313 
5314 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5315     uint8_t event[6];
5316     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5317     event[1] = sizeof(event) - 2u;
5318     event[2] = 0; // status = OK
5319     little_endian_store_16(event, 3, con_handle);
5320     event[5] = reason;
5321     hci_emit_event(event, sizeof(event), 1);
5322 }
5323 
5324 static void hci_emit_nr_connections_changed(void){
5325     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5326     uint8_t event[3];
5327     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5328     event[1] = sizeof(event) - 2u;
5329     event[2] = nr_hci_connections();
5330     hci_emit_event(event, sizeof(event), 1);
5331 }
5332 
5333 static void hci_emit_hci_open_failed(void){
5334     log_info("BTSTACK_EVENT_POWERON_FAILED");
5335     uint8_t event[2];
5336     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5337     event[1] = sizeof(event) - 2u;
5338     hci_emit_event(event, sizeof(event), 1);
5339 }
5340 
5341 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5342     log_info("hci_emit_dedicated_bonding_result %u ", status);
5343     uint8_t event[9];
5344     int pos = 0;
5345     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5346     event[pos++] = sizeof(event) - 2u;
5347     event[pos++] = status;
5348     reverse_bd_addr(address, &event[pos]);
5349     hci_emit_event(event, sizeof(event), 1);
5350 }
5351 
5352 
5353 #ifdef ENABLE_CLASSIC
5354 
5355 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5356     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5357     uint8_t event[5];
5358     int pos = 0;
5359     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5360     event[pos++] = sizeof(event) - 2;
5361     little_endian_store_16(event, 2, con_handle);
5362     pos += 2;
5363     event[pos++] = level;
5364     hci_emit_event(event, sizeof(event), 1);
5365 }
5366 
5367 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5368     if (!connection) return LEVEL_0;
5369     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5370     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5371     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5372     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5373     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5374     // LEVEL 4 always requires 128 bit encrytion key size
5375     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5376         security_level = LEVEL_3;
5377     }
5378     return security_level;
5379 }
5380 
5381 static void hci_emit_discoverable_enabled(uint8_t enabled){
5382     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5383     uint8_t event[3];
5384     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5385     event[1] = sizeof(event) - 2;
5386     event[2] = enabled;
5387     hci_emit_event(event, sizeof(event), 1);
5388 }
5389 
5390 // query if remote side supports eSCO
5391 int hci_remote_esco_supported(hci_con_handle_t con_handle){
5392     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5393     if (!connection) return 0;
5394     return (connection->remote_supported_features[0] & 1) != 0;
5395 }
5396 
5397 static bool hci_ssp_supported(hci_connection_t * connection){
5398     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5399     return (connection->bonding_flags & mask) == mask;
5400 }
5401 
5402 // query if remote side supports SSP
5403 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
5404     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5405     if (!connection) return 0;
5406     return hci_ssp_supported(connection) ? 1 : 0;
5407 }
5408 
5409 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5410     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5411 }
5412 
5413 // GAP API
5414 /**
5415  * @bbrief enable/disable bonding. default is enabled
5416  * @praram enabled
5417  */
5418 void gap_set_bondable_mode(int enable){
5419     hci_stack->bondable = enable ? 1 : 0;
5420 }
5421 /**
5422  * @brief Get bondable mode.
5423  * @return 1 if bondable
5424  */
5425 int gap_get_bondable_mode(void){
5426     return hci_stack->bondable;
5427 }
5428 
5429 /**
5430  * @brief map link keys to security levels
5431  */
5432 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5433     switch (link_key_type){
5434         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5435             return LEVEL_4;
5436         case COMBINATION_KEY:
5437         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5438             return LEVEL_3;
5439         default:
5440             return LEVEL_2;
5441     }
5442 }
5443 
5444 /**
5445  * @brief map link keys to secure connection yes/no
5446  */
5447 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5448     switch (link_key_type){
5449         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5450         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5451             return 1;
5452         default:
5453             return 0;
5454     }
5455 }
5456 
5457 /**
5458  * @brief map link keys to authenticated
5459  */
5460 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5461     switch (link_key_type){
5462         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5463         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5464             return 1;
5465         default:
5466             return 0;
5467     }
5468 }
5469 
5470 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5471     log_info("gap_mitm_protection_required_for_security_level %u", level);
5472     return level > LEVEL_2;
5473 }
5474 
5475 /**
5476  * @brief get current security level
5477  */
5478 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5479     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5480     if (!connection) return LEVEL_0;
5481     return gap_security_level_for_connection(connection);
5482 }
5483 
5484 /**
5485  * @brief request connection to device to
5486  * @result GAP_AUTHENTICATION_RESULT
5487  */
5488 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5489     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5490     if (!connection){
5491         hci_emit_security_level(con_handle, LEVEL_0);
5492         return;
5493     }
5494 
5495     btstack_assert(hci_is_le_connection(connection) == false);
5496 
5497     gap_security_level_t current_level = gap_security_level(con_handle);
5498     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5499         requested_level, connection->requested_security_level, current_level);
5500 
5501     // authentication active if authentication request was sent or planned level > 0
5502     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5503     if (authentication_active){
5504         // authentication already active
5505         if (connection->requested_security_level < requested_level){
5506             // increase requested level as new level is higher
5507             // TODO: handle re-authentication when done
5508             connection->requested_security_level = requested_level;
5509         }
5510     } else {
5511         // no request active, notify if security sufficient
5512         if (requested_level <= current_level){
5513             hci_emit_security_level(con_handle, current_level);
5514             return;
5515         }
5516 
5517         // store request
5518         connection->requested_security_level = requested_level;
5519 
5520         // start to authenticate connection
5521         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5522         hci_run();
5523     }
5524 }
5525 
5526 /**
5527  * @brief start dedicated bonding with device. disconnect after bonding
5528  * @param device
5529  * @param request MITM protection
5530  * @result GAP_DEDICATED_BONDING_COMPLETE
5531  */
5532 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5533 
5534     // create connection state machine
5535     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5536 
5537     if (!connection){
5538         return BTSTACK_MEMORY_ALLOC_FAILED;
5539     }
5540 
5541     // delete linkn key
5542     gap_drop_link_key_for_bd_addr(device);
5543 
5544     // configure LEVEL_2/3, dedicated bonding
5545     connection->state = SEND_CREATE_CONNECTION;
5546     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5547     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5548     connection->bonding_flags = BONDING_DEDICATED;
5549 
5550     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5551 
5552     // handle: connnection failure (connection complete != ok)
5553     // handle: authentication failure
5554     // handle: disconnect on done
5555 
5556     hci_run();
5557 
5558     return 0;
5559 }
5560 #endif
5561 
5562 void gap_set_local_name(const char * local_name){
5563     hci_stack->local_name = local_name;
5564 }
5565 
5566 
5567 #ifdef ENABLE_BLE
5568 
5569 #ifdef ENABLE_LE_CENTRAL
5570 void gap_start_scan(void){
5571     hci_stack->le_scanning_enabled = true;
5572     hci_run();
5573 }
5574 
5575 void gap_stop_scan(void){
5576     hci_stack->le_scanning_enabled = false;
5577     hci_run();
5578 }
5579 
5580 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5581     hci_stack->le_scan_type          = scan_type;
5582     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5583     hci_stack->le_scan_interval      = scan_interval;
5584     hci_stack->le_scan_window        = scan_window;
5585     hci_stack->le_scanning_param_update = true;
5586     hci_run();
5587 }
5588 
5589 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5590     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5591 }
5592 
5593 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5594     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5595     if (!conn){
5596         // disallow if le connection is already outgoing
5597         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5598             log_error("le connection already active");
5599             return ERROR_CODE_COMMAND_DISALLOWED;
5600         }
5601 
5602         log_info("gap_connect: no connection exists yet, creating context");
5603         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5604         if (!conn){
5605             // notify client that alloc failed
5606             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5607             log_info("gap_connect: failed to alloc hci_connection_t");
5608             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5609         }
5610 
5611         // set le connecting state
5612         if (hci_is_le_connection_type(addr_type)){
5613             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5614         }
5615 
5616         conn->state = SEND_CREATE_CONNECTION;
5617         log_info("gap_connect: send create connection next");
5618         hci_run();
5619         return ERROR_CODE_SUCCESS;
5620     }
5621 
5622     if (!hci_is_le_connection(conn) ||
5623         (conn->state == SEND_CREATE_CONNECTION) ||
5624         (conn->state == SENT_CREATE_CONNECTION)) {
5625         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5626         log_error("gap_connect: classic connection or connect is already being created");
5627         return GATT_CLIENT_IN_WRONG_STATE;
5628     }
5629 
5630     // check if connection was just disconnected
5631     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5632         log_info("gap_connect: send create connection (again)");
5633         conn->state = SEND_CREATE_CONNECTION;
5634         hci_run();
5635         return ERROR_CODE_SUCCESS;
5636     }
5637 
5638     log_info("gap_connect: context exists with state %u", conn->state);
5639     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5640     hci_run();
5641     return ERROR_CODE_SUCCESS;
5642 }
5643 
5644 // @assumption: only a single outgoing LE Connection exists
5645 static hci_connection_t * gap_get_outgoing_connection(void){
5646     btstack_linked_item_t *it;
5647     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5648         hci_connection_t * conn = (hci_connection_t *) it;
5649         if (!hci_is_le_connection(conn)) continue;
5650         switch (conn->state){
5651             case SEND_CREATE_CONNECTION:
5652             case SENT_CREATE_CONNECTION:
5653             case SENT_CANCEL_CONNECTION:
5654                 return conn;
5655             default:
5656                 break;
5657         };
5658     }
5659     return NULL;
5660 }
5661 
5662 uint8_t gap_connect_cancel(void){
5663     hci_connection_t * conn = gap_get_outgoing_connection();
5664     if (!conn) return 0;
5665     switch (conn->state){
5666         case SEND_CREATE_CONNECTION:
5667             // skip sending create connection and emit event instead
5668             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5669             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5670             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5671             btstack_memory_hci_connection_free( conn );
5672             break;
5673         case SENT_CREATE_CONNECTION:
5674             // request to send cancel connection
5675             conn->state = SEND_CANCEL_CONNECTION;
5676             hci_run();
5677             break;
5678         default:
5679             break;
5680     }
5681     return 0;
5682 }
5683 #endif
5684 
5685 #ifdef ENABLE_LE_CENTRAL
5686 /**
5687  * @brief Set connection parameters for outgoing connections
5688  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5689  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5690  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5691  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5692  * @param conn_latency, default: 4
5693  * @param supervision_timeout (unit: 10ms), default: 720 ms
5694  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5695  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5696  */
5697 
5698 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5699     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5700     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5701     hci_stack->le_connection_scan_interval = conn_scan_interval;
5702     hci_stack->le_connection_scan_window = conn_scan_window;
5703     hci_stack->le_connection_interval_min = conn_interval_min;
5704     hci_stack->le_connection_interval_max = conn_interval_max;
5705     hci_stack->le_connection_latency = conn_latency;
5706     hci_stack->le_supervision_timeout = supervision_timeout;
5707     hci_stack->le_minimum_ce_length = min_ce_length;
5708     hci_stack->le_maximum_ce_length = max_ce_length;
5709 }
5710 #endif
5711 
5712 /**
5713  * @brief Updates the connection parameters for a given LE connection
5714  * @param handle
5715  * @param conn_interval_min (unit: 1.25ms)
5716  * @param conn_interval_max (unit: 1.25ms)
5717  * @param conn_latency
5718  * @param supervision_timeout (unit: 10ms)
5719  * @returns 0 if ok
5720  */
5721 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5722     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5723     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5724     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5725     connection->le_conn_interval_min = conn_interval_min;
5726     connection->le_conn_interval_max = conn_interval_max;
5727     connection->le_conn_latency = conn_latency;
5728     connection->le_supervision_timeout = supervision_timeout;
5729     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5730     hci_run();
5731     return 0;
5732 }
5733 
5734 /**
5735  * @brief Request an update of the connection parameter for a given LE connection
5736  * @param handle
5737  * @param conn_interval_min (unit: 1.25ms)
5738  * @param conn_interval_max (unit: 1.25ms)
5739  * @param conn_latency
5740  * @param supervision_timeout (unit: 10ms)
5741  * @returns 0 if ok
5742  */
5743 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5744     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5745     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5746     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5747     connection->le_conn_interval_min = conn_interval_min;
5748     connection->le_conn_interval_max = conn_interval_max;
5749     connection->le_conn_latency = conn_latency;
5750     connection->le_supervision_timeout = supervision_timeout;
5751     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5752     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5753     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5754     return 0;
5755 }
5756 
5757 #ifdef ENABLE_LE_PERIPHERAL
5758 
5759 /**
5760  * @brief Set Advertisement Data
5761  * @param advertising_data_length
5762  * @param advertising_data (max 31 octets)
5763  * @note data is not copied, pointer has to stay valid
5764  */
5765 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5766     hci_stack->le_advertisements_data_len = advertising_data_length;
5767     hci_stack->le_advertisements_data = advertising_data;
5768     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5769     hci_run();
5770 }
5771 
5772 /**
5773  * @brief Set Scan Response Data
5774  * @param advertising_data_length
5775  * @param advertising_data (max 31 octets)
5776  * @note data is not copied, pointer has to stay valid
5777  */
5778 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5779     hci_stack->le_scan_response_data_len = scan_response_data_length;
5780     hci_stack->le_scan_response_data = scan_response_data;
5781     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5782     hci_run();
5783 }
5784 
5785 /**
5786  * @brief Set Advertisement Parameters
5787  * @param adv_int_min
5788  * @param adv_int_max
5789  * @param adv_type
5790  * @param direct_address_type
5791  * @param direct_address
5792  * @param channel_map
5793  * @param filter_policy
5794  *
5795  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5796  */
5797  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5798     uint8_t direct_address_typ, bd_addr_t direct_address,
5799     uint8_t channel_map, uint8_t filter_policy) {
5800 
5801     hci_stack->le_advertisements_interval_min = adv_int_min;
5802     hci_stack->le_advertisements_interval_max = adv_int_max;
5803     hci_stack->le_advertisements_type = adv_type;
5804     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5805     hci_stack->le_advertisements_channel_map = channel_map;
5806     hci_stack->le_advertisements_filter_policy = filter_policy;
5807     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5808                  6);
5809 
5810     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
5811     hci_run();
5812  }
5813 
5814 /**
5815  * @brief Enable/Disable Advertisements
5816  * @param enabled
5817  */
5818 void gap_advertisements_enable(int enabled){
5819     hci_stack->le_advertisements_enabled = enabled != 0;
5820     hci_update_advertisements_enabled_for_current_roles();
5821     hci_run();
5822 }
5823 
5824 #endif
5825 
5826 void hci_le_set_own_address_type(uint8_t own_address_type){
5827     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5828     if (own_address_type == hci_stack->le_own_addr_type) return;
5829     hci_stack->le_own_addr_type = own_address_type;
5830 
5831 #ifdef ENABLE_LE_PERIPHERAL
5832     // update advertisement parameters, too
5833     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5834     hci_run();
5835 #endif
5836 #ifdef ENABLE_LE_CENTRAL
5837     // note: we don't update scan parameters or modify ongoing connection attempts
5838 #endif
5839 }
5840 
5841 #endif
5842 
5843 uint8_t gap_disconnect(hci_con_handle_t handle){
5844     hci_connection_t * conn = hci_connection_for_handle(handle);
5845     if (!conn){
5846         hci_emit_disconnection_complete(handle, 0);
5847         return 0;
5848     }
5849     // ignore if already disconnected
5850     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5851         return 0;
5852     }
5853     conn->state = SEND_DISCONNECT;
5854     hci_run();
5855     return 0;
5856 }
5857 
5858 int gap_read_rssi(hci_con_handle_t con_handle){
5859     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5860     if (hci_connection == NULL) return 0;
5861     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5862     hci_run();
5863     return 1;
5864 }
5865 
5866 /**
5867  * @brief Get connection type
5868  * @param con_handle
5869  * @result connection_type
5870  */
5871 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5872     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5873     if (!conn) return GAP_CONNECTION_INVALID;
5874     switch (conn->address_type){
5875         case BD_ADDR_TYPE_LE_PUBLIC:
5876         case BD_ADDR_TYPE_LE_RANDOM:
5877             return GAP_CONNECTION_LE;
5878         case BD_ADDR_TYPE_SCO:
5879             return GAP_CONNECTION_SCO;
5880         case BD_ADDR_TYPE_ACL:
5881             return GAP_CONNECTION_ACL;
5882         default:
5883             return GAP_CONNECTION_INVALID;
5884     }
5885 }
5886 
5887 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5888     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5889     if (!conn) return HCI_ROLE_INVALID;
5890     return (hci_role_t) conn->role;
5891 }
5892 
5893 
5894 #ifdef ENABLE_CLASSIC
5895 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
5896     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5897     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5898     conn->request_role = role;
5899     hci_run();
5900     return ERROR_CODE_SUCCESS;
5901 }
5902 #endif
5903 
5904 #ifdef ENABLE_BLE
5905 
5906 uint8_t gap_le_set_phy(hci_con_handle_t con_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
5907     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5908     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5909 
5910     conn->le_phy_update_all_phys    = all_phys;
5911     conn->le_phy_update_tx_phys     = tx_phys;
5912     conn->le_phy_update_rx_phys     = rx_phys;
5913     conn->le_phy_update_phy_options = phy_options;
5914 
5915     hci_run();
5916 
5917     return 0;
5918 }
5919 
5920 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
5921     // check if already in list
5922     btstack_linked_list_iterator_t it;
5923     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5924     while (btstack_linked_list_iterator_has_next(&it)) {
5925         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5926         if (entry->address_type != address_type) {
5927             continue;
5928         }
5929         if (memcmp(entry->address, address, 6) != 0) {
5930             continue;
5931         }
5932 		// disallow if already scheduled to add
5933 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
5934 			return ERROR_CODE_COMMAND_DISALLOWED;
5935 		}
5936 		// still on controller, but scheduled to remove -> re-add
5937 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
5938 		return ERROR_CODE_SUCCESS;
5939     }
5940     // alloc and add to list
5941     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5942     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5943     entry->address_type = address_type;
5944     (void)memcpy(entry->address, address, 6);
5945     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5946     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5947     return ERROR_CODE_SUCCESS;
5948 }
5949 
5950 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
5951     btstack_linked_list_iterator_t it;
5952     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5953     while (btstack_linked_list_iterator_has_next(&it)){
5954         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5955         if (entry->address_type != address_type) {
5956             continue;
5957         }
5958         if (memcmp(entry->address, address, 6) != 0) {
5959             continue;
5960         }
5961         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5962             // remove from controller if already present
5963             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5964         }  else {
5965             // directly remove entry from whitelist
5966             btstack_linked_list_iterator_remove(&it);
5967             btstack_memory_whitelist_entry_free(entry);
5968         }
5969         return ERROR_CODE_SUCCESS;
5970     }
5971     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5972 }
5973 
5974 static void hci_whitelist_clear(void){
5975     btstack_linked_list_iterator_t it;
5976     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5977     while (btstack_linked_list_iterator_has_next(&it)){
5978         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5979         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5980             // remove from controller if already present
5981             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5982             continue;
5983         }
5984         // directly remove entry from whitelist
5985         btstack_linked_list_iterator_remove(&it);
5986         btstack_memory_whitelist_entry_free(entry);
5987     }
5988 }
5989 
5990 /**
5991  * @brief Clear Whitelist
5992  * @returns 0 if ok
5993  */
5994 uint8_t gap_whitelist_clear(void){
5995     hci_whitelist_clear();
5996     hci_run();
5997     return ERROR_CODE_SUCCESS;
5998 }
5999 
6000 /**
6001  * @brief Add Device to Whitelist
6002  * @param address_typ
6003  * @param address
6004  * @returns 0 if ok
6005  */
6006 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6007     uint8_t status = hci_whitelist_add(address_type, address);
6008     if (status){
6009         return status;
6010     }
6011     hci_run();
6012     return ERROR_CODE_SUCCESS;
6013 }
6014 
6015 /**
6016  * @brief Remove Device from Whitelist
6017  * @param address_typ
6018  * @param address
6019  * @returns 0 if ok
6020  */
6021 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6022     uint8_t status = hci_whitelist_remove(address_type, address);
6023     if (status){
6024         return status;
6025     }
6026     hci_run();
6027     return ERROR_CODE_SUCCESS;
6028 }
6029 
6030 #ifdef ENABLE_LE_CENTRAL
6031 /**
6032  *  @brief Connect with Whitelist
6033  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6034  *  @returns - if ok
6035  */
6036 uint8_t gap_connect_with_whitelist(void){
6037     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6038         return ERROR_CODE_COMMAND_DISALLOWED;
6039     }
6040     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6041     hci_run();
6042     return ERROR_CODE_SUCCESS;
6043 }
6044 
6045 /**
6046  * @brief Auto Connection Establishment - Start Connecting to device
6047  * @param address_typ
6048  * @param address
6049  * @returns 0 if ok
6050  */
6051 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6052     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6053         return ERROR_CODE_COMMAND_DISALLOWED;
6054     }
6055 
6056     uint8_t status = hci_whitelist_add(address_type, address);
6057     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6058         return status;
6059     }
6060 
6061     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6062 
6063     hci_run();
6064     return ERROR_CODE_SUCCESS;
6065 }
6066 
6067 /**
6068  * @brief Auto Connection Establishment - Stop Connecting to device
6069  * @param address_typ
6070  * @param address
6071  * @returns 0 if ok
6072  */
6073 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6074     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6075         return ERROR_CODE_COMMAND_DISALLOWED;
6076     }
6077 
6078     hci_whitelist_remove(address_type, address);
6079     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6080         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6081     }
6082     hci_run();
6083     return 0;
6084 }
6085 
6086 /**
6087  * @brief Auto Connection Establishment - Stop everything
6088  * @note  Convenience function to stop all active auto connection attempts
6089  */
6090 uint8_t gap_auto_connection_stop_all(void){
6091     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6092         return ERROR_CODE_COMMAND_DISALLOWED;
6093     }
6094     hci_whitelist_clear();
6095     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6096     hci_run();
6097     return ERROR_CODE_SUCCESS;
6098 }
6099 
6100 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6101     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6102     if (!conn) return 0;
6103     return conn->le_connection_interval;
6104 }
6105 #endif
6106 #endif
6107 
6108 #ifdef ENABLE_CLASSIC
6109 /**
6110  * @brief Set Extended Inquiry Response data
6111  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6112  * @note has to be done before stack starts up
6113  */
6114 void gap_set_extended_inquiry_response(const uint8_t * data){
6115     hci_stack->eir_data = data;
6116 }
6117 
6118 /**
6119  * @brief Start GAP Classic Inquiry
6120  * @param duration in 1.28s units
6121  * @return 0 if ok
6122  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6123  */
6124 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6125     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6126     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6127     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6128         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6129     }
6130     hci_stack->inquiry_state = duration_in_1280ms_units;
6131     hci_run();
6132     return 0;
6133 }
6134 
6135 /**
6136  * @brief Stop GAP Classic Inquiry
6137  * @returns 0 if ok
6138  */
6139 int gap_inquiry_stop(void){
6140     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6141         // emit inquiry complete event, before it even started
6142         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6143         hci_emit_event(event, sizeof(event), 1);
6144         return 0;
6145     }
6146     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6147     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6148     hci_run();
6149     return 0;
6150 }
6151 
6152 void gap_inquiry_set_lap(uint32_t lap){
6153     hci_stack->inquiry_lap = lap;
6154 }
6155 
6156 
6157 /**
6158  * @brief Remote Name Request
6159  * @param addr
6160  * @param page_scan_repetition_mode
6161  * @param clock_offset only used when bit 15 is set
6162  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6163  */
6164 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6165     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6166     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6167     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6168     hci_stack->remote_name_clock_offset = clock_offset;
6169     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6170     hci_run();
6171     return 0;
6172 }
6173 
6174 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6175     hci_stack->gap_pairing_state = state;
6176     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6177     hci_run();
6178     return 0;
6179 }
6180 
6181 /**
6182  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6183  * @param addr
6184  * @param pin_data
6185  * @param pin_len
6186  * @return 0 if ok
6187  */
6188 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6189     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6190     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6191     hci_stack->gap_pairing_pin_len = pin_len;
6192     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6193 }
6194 
6195 /**
6196  * @brief Legacy Pairing Pin Code Response
6197  * @param addr
6198  * @param pin
6199  * @return 0 if ok
6200  */
6201 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6202     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6203 }
6204 
6205 /**
6206  * @brief Abort Legacy Pairing
6207  * @param addr
6208  * @param pin
6209  * @return 0 if ok
6210  */
6211 int gap_pin_code_negative(bd_addr_t addr){
6212     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6213     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6214 }
6215 
6216 /**
6217  * @brief SSP Passkey Response
6218  * @param addr
6219  * @param passkey
6220  * @return 0 if ok
6221  */
6222 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6223     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6224     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6225     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6226 }
6227 
6228 /**
6229  * @brief Abort SSP Passkey Entry/Pairing
6230  * @param addr
6231  * @param pin
6232  * @return 0 if ok
6233  */
6234 int gap_ssp_passkey_negative(const bd_addr_t addr){
6235     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6236     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6237 }
6238 
6239 /**
6240  * @brief Accept SSP Numeric Comparison
6241  * @param addr
6242  * @param passkey
6243  * @return 0 if ok
6244  */
6245 int gap_ssp_confirmation_response(const bd_addr_t addr){
6246     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6247     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6248 }
6249 
6250 /**
6251  * @brief Abort SSP Numeric Comparison/Pairing
6252  * @param addr
6253  * @param pin
6254  * @return 0 if ok
6255  */
6256 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6257     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6258     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6259 }
6260 
6261 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6262 
6263 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6264     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6265     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6266     connectionSetAuthenticationFlags(conn, flag);
6267     hci_run();
6268     return ERROR_CODE_SUCCESS;
6269 }
6270 
6271 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6272     return gap_set_auth_flag_and_run(addr, SEND_IO_CAPABILITIES_REPLY);
6273 }
6274 
6275 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6276     return gap_set_auth_flag_and_run(addr, SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6277 }
6278 #endif
6279 
6280 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6281 /**
6282  * @brief Report Remote OOB Data
6283  * @param bd_addr
6284  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6285  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6286  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6287  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6288  */
6289 uint8_t gap_ssp_remote_oob_data(const bd_addr_t addr, const uint8_t * c_192, const uint8_t * r_192, const uint8_t * c_256, const uint8_t * r_256){
6290     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6291     if (connection == NULL) {
6292         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6293     }
6294     connection->classic_oob_c_192 = c_192;
6295     connection->classic_oob_r_192 = r_192;
6296     connection->classic_oob_c_256 = c_256;
6297     connection->classic_oob_r_256 = r_256;
6298     return ERROR_CODE_SUCCESS;
6299 }
6300 /**
6301  * @brief Generate new OOB data
6302  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6303  */
6304 void gap_ssp_generate_oob_data(void){
6305     hci_stack->classic_read_local_oob_data = true;
6306     hci_run();
6307 }
6308 
6309 #endif
6310 
6311 /**
6312  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6313  * @param inquiry_mode see bluetooth_defines.h
6314  */
6315 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6316     hci_stack->inquiry_mode = inquiry_mode;
6317 }
6318 
6319 /**
6320  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6321  */
6322 void hci_set_sco_voice_setting(uint16_t voice_setting){
6323     hci_stack->sco_voice_setting = voice_setting;
6324 }
6325 
6326 /**
6327  * @brief Get SCO Voice Setting
6328  * @return current voice setting
6329  */
6330 uint16_t hci_get_sco_voice_setting(void){
6331     return hci_stack->sco_voice_setting;
6332 }
6333 
6334 static int hci_have_usb_transport(void){
6335     if (!hci_stack->hci_transport) return 0;
6336     const char * transport_name = hci_stack->hci_transport->name;
6337     if (!transport_name) return 0;
6338     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6339 }
6340 
6341 /** @brief Get SCO packet length for current SCO Voice setting
6342  *  @note  Using SCO packets of the exact length is required for USB transfer
6343  *  @return Length of SCO packets in bytes (not audio frames)
6344  */
6345 int hci_get_sco_packet_length(void){
6346     int sco_packet_length = 0;
6347 
6348 #ifdef ENABLE_SCO_OVER_HCI
6349     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6350     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6351 
6352     if (hci_have_usb_transport()){
6353         // see Core Spec for H2 USB Transfer.
6354         // 3 byte SCO header + 24 bytes per connection
6355         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6356         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6357     } else {
6358         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6359         sco_packet_length = 3 + 60 * multiplier;
6360         // assert that it still fits inside an SCO buffer
6361         if (sco_packet_length > hci_stack->sco_data_packet_length){
6362             sco_packet_length = 3 + 60;
6363         }
6364     }
6365 #endif
6366 
6367 #ifdef HAVE_SCO_TRANSPORT
6368     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6369     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6370     sco_packet_length = 3 + 60 * multiplier;
6371 #endif
6372     return sco_packet_length;
6373 }
6374 
6375 /**
6376 * @brief Sets the master/slave policy
6377 * @param policy (0: attempt to become master, 1: let connecting device decide)
6378 */
6379 void hci_set_master_slave_policy(uint8_t policy){
6380     hci_stack->master_slave_policy = policy;
6381 }
6382 
6383 #endif
6384 
6385 HCI_STATE hci_get_state(void){
6386     return hci_stack->state;
6387 }
6388 
6389 #ifdef ENABLE_CLASSIC
6390 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6391     hci_stack->gap_classic_accept_callback = accept_callback;
6392 }
6393 #endif
6394 
6395 /**
6396  * @brief Set callback for Bluetooth Hardware Error
6397  */
6398 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6399     hci_stack->hardware_error_callback = fn;
6400 }
6401 
6402 void hci_disconnect_all(void){
6403     btstack_linked_list_iterator_t it;
6404     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6405     while (btstack_linked_list_iterator_has_next(&it)){
6406         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6407         if (con->state == SENT_DISCONNECT) continue;
6408         con->state = SEND_DISCONNECT;
6409     }
6410     hci_run();
6411 }
6412 
6413 uint16_t hci_get_manufacturer(void){
6414     return hci_stack->manufacturer;
6415 }
6416 
6417 #ifdef ENABLE_BLE
6418 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6419     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6420     if (!hci_con) return NULL;
6421     return &hci_con->sm_connection;
6422 }
6423 
6424 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6425 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6426 #endif
6427 
6428 int gap_encryption_key_size(hci_con_handle_t con_handle){
6429     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6430     if (hci_connection == NULL) return 0;
6431     if (hci_is_le_connection(hci_connection)){
6432 #ifdef ENABLE_BLE
6433         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6434         if (sm_conn->sm_connection_encrypted) {
6435             return sm_conn->sm_actual_encryption_key_size;
6436         }
6437 #endif
6438     } else {
6439 #ifdef ENABLE_CLASSIC
6440         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
6441             return hci_connection->encryption_key_size;
6442         }
6443 #endif
6444     }
6445     return 0;
6446 }
6447 
6448 int gap_authenticated(hci_con_handle_t con_handle){
6449     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6450     if (hci_connection == NULL) return 0;
6451 
6452     switch (hci_connection->address_type){
6453 #ifdef ENABLE_BLE
6454         case BD_ADDR_TYPE_LE_PUBLIC:
6455         case BD_ADDR_TYPE_LE_RANDOM:
6456             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6457             return hci_connection->sm_connection.sm_connection_authenticated;
6458 #endif
6459 #ifdef ENABLE_CLASSIC
6460         case BD_ADDR_TYPE_SCO:
6461         case BD_ADDR_TYPE_ACL:
6462             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6463 #endif
6464         default:
6465             return 0;
6466     }
6467 }
6468 
6469 int gap_secure_connection(hci_con_handle_t con_handle){
6470     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6471     if (hci_connection == NULL) return 0;
6472 
6473     switch (hci_connection->address_type){
6474 #ifdef ENABLE_BLE
6475         case BD_ADDR_TYPE_LE_PUBLIC:
6476         case BD_ADDR_TYPE_LE_RANDOM:
6477             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6478             return hci_connection->sm_connection.sm_connection_sc;
6479 #endif
6480 #ifdef ENABLE_CLASSIC
6481         case BD_ADDR_TYPE_SCO:
6482         case BD_ADDR_TYPE_ACL:
6483             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6484 #endif
6485         default:
6486             return 0;
6487     }
6488 }
6489 
6490 bool gap_bonded(hci_con_handle_t con_handle){
6491 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6492 	if (hci_connection == NULL) return 0;
6493 
6494 #ifdef ENABLE_CLASSIC
6495 	link_key_t link_key;
6496 	link_key_type_t link_key_type;
6497 #endif
6498 	switch (hci_connection->address_type){
6499 #ifdef ENABLE_BLE
6500 		case BD_ADDR_TYPE_LE_PUBLIC:
6501 		case BD_ADDR_TYPE_LE_RANDOM:
6502 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6503 #endif
6504 #ifdef ENABLE_CLASSIC
6505 		case BD_ADDR_TYPE_SCO:
6506 		case BD_ADDR_TYPE_ACL:
6507 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6508 #endif
6509 		default:
6510 			return false;
6511 	}
6512 }
6513 
6514 #ifdef ENABLE_BLE
6515 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6516     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6517     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6518     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6519     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6520     return sm_conn->sm_connection_authorization_state;
6521 }
6522 #endif
6523 
6524 #ifdef ENABLE_CLASSIC
6525 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){
6526     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6527     if (!conn) return GAP_CONNECTION_INVALID;
6528     conn->sniff_min_interval = sniff_min_interval;
6529     conn->sniff_max_interval = sniff_max_interval;
6530     conn->sniff_attempt = sniff_attempt;
6531     conn->sniff_timeout = sniff_timeout;
6532     hci_run();
6533     return 0;
6534 }
6535 
6536 /**
6537  * @brief Exit Sniff mode
6538  * @param con_handle
6539  @ @return 0 if ok
6540  */
6541 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6542     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6543     if (!conn) return GAP_CONNECTION_INVALID;
6544     conn->sniff_min_interval = 0xffff;
6545     hci_run();
6546     return 0;
6547 }
6548 
6549 uint8_t gap_sniff_subrating_configure(hci_con_handle_t con_handle, uint16_t max_latency, uint16_t min_remote_timeout, uint16_t min_local_timeout){
6550     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6551     if (!conn) return GAP_CONNECTION_INVALID;
6552     conn->sniff_subrating_max_latency = max_latency;
6553     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6554     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6555     hci_run();
6556     return ERROR_CODE_SUCCESS;
6557 }
6558 
6559 uint8_t gap_qos_set(hci_con_handle_t con_handle, hci_service_type_t service_type, uint32_t token_rate, uint32_t peak_bandwidth, uint32_t latency, uint32_t delay_variation){
6560     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6561     if (!conn) return GAP_CONNECTION_INVALID;
6562     conn->qos_service_type = service_type;
6563     conn->qos_token_rate = token_rate;
6564     conn->qos_peak_bandwidth = peak_bandwidth;
6565     conn->qos_latency = latency;
6566     conn->qos_delay_variation = delay_variation;
6567     hci_run();
6568     return ERROR_CODE_SUCCESS;
6569 }
6570 
6571 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6572     hci_stack->new_page_scan_interval = page_scan_interval;
6573     hci_stack->new_page_scan_window = page_scan_window;
6574     hci_run();
6575 }
6576 
6577 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6578     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6579     hci_run();
6580 }
6581 
6582 #endif
6583 
6584 void hci_halting_defer(void){
6585     if (hci_stack->state != HCI_STATE_HALTING) return;
6586     switch (hci_stack->substate){
6587         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6588         case HCI_HALTING_CLOSE:
6589             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6590             break;
6591         default:
6592             break;
6593     }
6594 }
6595 
6596 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6597 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6598     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6599     if (le_device_db_index >= le_device_db_max_count()) return;
6600     uint8_t offset = le_device_db_index >> 3;
6601     uint8_t mask = 1 << (le_device_db_index & 7);
6602     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6603     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6604     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6605         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6606     }
6607 }
6608 
6609 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6610 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6611 	if (le_device_db_index >= le_device_db_max_count()) return;
6612 	uint8_t offset = le_device_db_index >> 3;
6613 	uint8_t mask = 1 << (le_device_db_index & 7);
6614 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6615 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6616 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6617 	}
6618 }
6619 
6620 uint8_t gap_load_resolving_list_from_le_device_db(void){
6621 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6622 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6623 	}
6624 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6625 		// restart le resolving list update
6626 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6627 	}
6628 	return ERROR_CODE_SUCCESS;
6629 }
6630 #endif
6631 
6632 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6633 void hci_setup_test_connections_fuzz(void){
6634     hci_connection_t * conn;
6635 
6636     // default address: 66:55:44:33:00:01
6637     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6638 
6639     // setup Controller info
6640     hci_stack->num_cmd_packets = 255;
6641     hci_stack->acl_packets_total_num = 255;
6642 
6643     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6644     addr[5] = 0x01;
6645     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6646     conn->con_handle = addr[5];
6647     conn->role  = HCI_ROLE_SLAVE;
6648     conn->state = RECEIVED_CONNECTION_REQUEST;
6649     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6650 
6651     // setup incoming Classic SCO connection with con handle 0x0002
6652     addr[5] = 0x02;
6653     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6654     conn->con_handle = addr[5];
6655     conn->role  = HCI_ROLE_SLAVE;
6656     conn->state = RECEIVED_CONNECTION_REQUEST;
6657     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6658 
6659     // setup ready Classic ACL connection with con handle 0x0003
6660     addr[5] = 0x03;
6661     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6662     conn->con_handle = addr[5];
6663     conn->role  = HCI_ROLE_SLAVE;
6664     conn->state = OPEN;
6665     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6666 
6667     // setup ready Classic SCO connection with con handle 0x0004
6668     addr[5] = 0x04;
6669     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6670     conn->con_handle = addr[5];
6671     conn->role  = HCI_ROLE_SLAVE;
6672     conn->state = OPEN;
6673     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6674 
6675     // setup ready LE ACL connection with con handle 0x005 and public address
6676     addr[5] = 0x05;
6677     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6678     conn->con_handle = addr[5];
6679     conn->role  = HCI_ROLE_SLAVE;
6680     conn->state = OPEN;
6681     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6682     conn->sm_connection.sm_connection_encrypted = 1;
6683 }
6684 
6685 void hci_free_connections_fuzz(void){
6686     btstack_linked_list_iterator_t it;
6687     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6688     while (btstack_linked_list_iterator_has_next(&it)){
6689         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6690         btstack_linked_list_iterator_remove(&it);
6691         btstack_memory_hci_connection_free(con);
6692     }
6693 }
6694 void hci_simulate_working_fuzz(void){
6695     hci_init_done();
6696     hci_stack->num_cmd_packets = 255;
6697 }
6698 #endif
6699