xref: /btstack/src/hci.c (revision 6ffc78ce3010a53c0092b99677b6c14f867dc974)
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 ENABLE_BLE
57 #include "gap.h"
58 #include "ble/le_device_db.h"
59 #endif
60 
61 #include <stdarg.h>
62 #include <string.h>
63 #include <inttypes.h>
64 
65 #include "btstack_debug.h"
66 #include "btstack_event.h"
67 #include "btstack_linked_list.h"
68 #include "btstack_memory.h"
69 #include "bluetooth_company_id.h"
70 #include "bluetooth_data_types.h"
71 #include "gap.h"
72 #include "hci.h"
73 #include "hci_cmd.h"
74 #include "hci_dump.h"
75 #include "ad_parser.h"
76 
77 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
78 #ifndef HCI_HOST_ACL_PACKET_NUM
79 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
80 #endif
81 #ifndef HCI_HOST_ACL_PACKET_LEN
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
83 #endif
84 #ifndef HCI_HOST_SCO_PACKET_NUM
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_LEN
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
89 #endif
90 #endif
91 
92 #if defined(ENABLE_SCO_OVER_HCI) && defined(ENABLE_SCO_OVER_PCM)
93 #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."
94 #endif
95 
96 #if defined(ENABLE_SCO_OVER_HCI) && defined(HAVE_SCO_TRANSPORT)
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 HAVE_SCO_TRANSPORT."
98 #endif
99 
100 #define HCI_CONNECTION_TIMEOUT_MS 10000
101 
102 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
103 #define HCI_RESET_RESEND_TIMEOUT_MS 200
104 #endif
105 
106 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
107 #ifndef GAP_INQUIRY_MAX_NAME_LEN
108 #define GAP_INQUIRY_MAX_NAME_LEN 32
109 #endif
110 
111 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
112 #define GAP_INQUIRY_DURATION_MIN       0x01
113 #define GAP_INQUIRY_DURATION_MAX       0x30
114 #define GAP_INQUIRY_STATE_IDLE         0x00
115 #define GAP_INQUIRY_STATE_W4_ACTIVE    0x80
116 #define GAP_INQUIRY_STATE_ACTIVE       0x81
117 #define GAP_INQUIRY_STATE_W2_CANCEL    0x82
118 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x83
119 
120 // GAP Remote Name Request
121 #define GAP_REMOTE_NAME_STATE_IDLE 0
122 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
123 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
124 
125 // GAP Pairing
126 #define GAP_PAIRING_STATE_IDLE                       0
127 #define GAP_PAIRING_STATE_SEND_PIN                   1
128 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
129 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
130 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
131 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
132 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
133 #define GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE  7
134 
135 // prototypes
136 #ifdef ENABLE_CLASSIC
137 static void hci_update_scan_enable(void);
138 static void hci_emit_discoverable_enabled(uint8_t enabled);
139 static int  hci_local_ssp_activated(void);
140 static bool hci_remote_ssp_supported(hci_con_handle_t con_handle);
141 static bool hci_ssp_supported(hci_connection_t * connection);
142 static void hci_notify_if_sco_can_send_now(void);
143 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
144 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
145 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
146 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
147 static void hci_connection_timestamp(hci_connection_t *connection);
148 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
149 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
150 #endif
151 
152 static int  hci_power_control_on(void);
153 static void hci_power_control_off(void);
154 static void hci_state_reset(void);
155 static void hci_emit_transport_packet_sent(void);
156 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
157 static void hci_emit_nr_connections_changed(void);
158 static void hci_emit_hci_open_failed(void);
159 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
160 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
161 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
162 static void hci_run(void);
163 static int  hci_is_le_connection(hci_connection_t * connection);
164 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
165 
166 #ifdef ENABLE_CLASSIC
167 static int hci_have_usb_transport(void);
168 #endif
169 
170 #ifdef ENABLE_BLE
171 #ifdef ENABLE_LE_CENTRAL
172 // called from test/ble_client/advertising_data_parser.c
173 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
174 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address);
175 static hci_connection_t * gap_get_outgoing_connection(void);
176 #endif
177 #endif
178 
179 // the STACK is here
180 #ifndef HAVE_MALLOC
181 static hci_stack_t   hci_stack_static;
182 #endif
183 static hci_stack_t * hci_stack = NULL;
184 
185 #ifdef ENABLE_CLASSIC
186 // default name
187 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
188 
189 // test helper
190 static uint8_t disable_l2cap_timeouts = 0;
191 #endif
192 
193 // reset connection state on create and on reconnect
194 // don't overwrite addr, con handle, role
195 static void hci_connection_init(hci_connection_t * conn){
196     conn->authentication_flags = AUTH_FLAG_NONE;
197     conn->bonding_flags = 0;
198     conn->requested_security_level = LEVEL_0;
199 #ifdef ENABLE_CLASSIC
200     conn->request_role = HCI_ROLE_INVALID;
201     conn->sniff_subrating_max_latency = 0xffff;
202     conn->qos_service_type = HCI_SERVICE_TYPE_INVALID;
203     conn->link_key_type = INVALID_LINK_KEY;
204     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
205     btstack_run_loop_set_timer_context(&conn->timeout, conn);
206     hci_connection_timestamp(conn);
207 #endif
208     conn->acl_recombination_length = 0;
209     conn->acl_recombination_pos = 0;
210     conn->num_packets_sent = 0;
211 
212     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
213 #ifdef ENABLE_BLE
214     conn->le_phy_update_all_phys = 0xff;
215 #endif
216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
217     conn->le_max_tx_octets = 27;
218 #endif
219 #ifdef ENABLE_CLASSIC_PAIRING_OOB
220     conn->classic_oob_c_192 = NULL;
221     conn->classic_oob_r_192 = NULL;
222     conn->classic_oob_c_256 = NULL;
223     conn->classic_oob_r_256 = NULL;
224 #endif
225 }
226 
227 /**
228  * create connection for given address
229  *
230  * @return connection OR NULL, if no memory left
231  */
232 static hci_connection_t * create_connection_for_bd_addr_and_type(const bd_addr_t addr, bd_addr_type_t addr_type){
233     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
234 
235     hci_connection_t * conn = btstack_memory_hci_connection_get();
236     if (!conn) return NULL;
237     hci_connection_init(conn);
238 
239     bd_addr_copy(conn->address, addr);
240     conn->address_type = addr_type;
241     conn->con_handle = HCI_CON_HANDLE_INVALID;
242     conn->role = HCI_ROLE_INVALID;
243 
244     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
245 
246     return conn;
247 }
248 
249 
250 /**
251  * get le connection parameter range
252 *
253  * @return le connection parameter range struct
254  */
255 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
256     *range = hci_stack->le_connection_parameter_range;
257 }
258 
259 /**
260  * set le connection parameter range
261  *
262  */
263 
264 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
265     hci_stack->le_connection_parameter_range = *range;
266 }
267 
268 /**
269  * @brief Test if connection parameters are inside in existing rage
270  * @param conn_interval_min (unit: 1.25ms)
271  * @param conn_interval_max (unit: 1.25ms)
272  * @param conn_latency
273  * @param supervision_timeout (unit: 10ms)
274  * @returns 1 if included
275  */
276 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){
277     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
278     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
279 
280     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
281     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
282 
283     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
284     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
285 
286     return 1;
287 }
288 
289 /**
290  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
291  * @note: default: 1
292  * @param max_peripheral_connections
293  */
294 #ifdef ENABLE_LE_PERIPHERAL
295 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
296     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
297 }
298 #endif
299 
300 /**
301  * get hci connections iterator
302  *
303  * @return hci connections iterator
304  */
305 
306 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
307     btstack_linked_list_iterator_init(it, &hci_stack->connections);
308 }
309 
310 /**
311  * get connection for a given handle
312  *
313  * @return connection OR NULL, if not found
314  */
315 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
316     btstack_linked_list_iterator_t it;
317     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
318     while (btstack_linked_list_iterator_has_next(&it)){
319         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
320         if ( item->con_handle == con_handle ) {
321             return item;
322         }
323     }
324     return NULL;
325 }
326 
327 /**
328  * get connection for given address
329  *
330  * @return connection OR NULL, if not found
331  */
332 hci_connection_t * hci_connection_for_bd_addr_and_type(const bd_addr_t  addr, bd_addr_type_t addr_type){
333     btstack_linked_list_iterator_t it;
334     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
335     while (btstack_linked_list_iterator_has_next(&it)){
336         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
337         if (connection->address_type != addr_type)  continue;
338         if (memcmp(addr, connection->address, 6) != 0) continue;
339         return connection;
340     }
341     return NULL;
342 }
343 
344 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
345     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
346 }
347 
348 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
349     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
350 }
351 
352 #ifdef ENABLE_CLASSIC
353 
354 #ifdef ENABLE_SCO_OVER_HCI
355 static int hci_number_sco_connections(void){
356     int connections = 0;
357     btstack_linked_list_iterator_t it;
358     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
359     while (btstack_linked_list_iterator_has_next(&it)){
360         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
361         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
362         connections++;
363     }
364     return connections;
365 }
366 #endif
367 
368 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
369     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
370 #ifdef HAVE_EMBEDDED_TICK
371     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
372         // connections might be timed out
373         hci_emit_l2cap_check_timeout(connection);
374     }
375 #else
376     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
377         // connections might be timed out
378         hci_emit_l2cap_check_timeout(connection);
379     }
380 #endif
381 }
382 
383 static void hci_connection_timestamp(hci_connection_t *connection){
384 #ifdef HAVE_EMBEDDED_TICK
385     connection->timestamp = btstack_run_loop_embedded_get_ticks();
386 #else
387     connection->timestamp = btstack_run_loop_get_time_ms();
388 #endif
389 }
390 
391 /**
392  * add authentication flags and reset timer
393  * @note: assumes classic connection
394  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
395  */
396 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
397     bd_addr_t addr;
398     reverse_bd_addr(bd_addr, addr);
399     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
400     if (conn) {
401         connectionSetAuthenticationFlags(conn, flags);
402         hci_connection_timestamp(conn);
403     }
404 }
405 
406 static bool hci_pairing_active(hci_connection_t * hci_connection){
407     return (hci_connection->authentication_flags & AUTH_FLAG_PAIRING_ACTIVE_MASK) != 0;
408 }
409 
410 static void hci_pairing_started(hci_connection_t * hci_connection, bool ssp){
411     if (hci_pairing_active(hci_connection)) return;
412     if (ssp){
413         hci_connection->authentication_flags |= AUTH_FLAG_SSP_PAIRING_ACTIVE;
414     } else {
415         hci_connection->authentication_flags |= AUTH_FLAG_LEGACY_PAIRING_ACTIVE;
416     }
417     // if we are initiator, we have sent an HCI Authenticate Request
418     bool initiator = (hci_connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0;
419 
420     // if we are responder, use minimal service security level as required level
421     if (!initiator){
422         hci_connection->requested_security_level = (gap_security_level_t) btstack_max((uint32_t) hci_connection->requested_security_level, (uint32_t) hci_stack->gap_minimal_service_security_level);
423     }
424 
425     log_info("pairing started, ssp %u, initiator %u, requested level %u", (int) ssp, (int) initiator, hci_connection->requested_security_level);
426 
427     uint8_t event[12];
428     event[0] = GAP_EVENT_PAIRING_STARTED;
429     event[1] = 10;
430     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
431     reverse_bd_addr(hci_connection->address, &event[4]);
432     event[10] = (uint8_t) ssp;
433     event[11] = (uint8_t) initiator;
434     hci_emit_event(event, sizeof(event), 1);
435 }
436 
437 static void hci_pairing_complete(hci_connection_t * hci_connection, uint8_t status){
438     hci_connection->requested_security_level = LEVEL_0;
439     if (!hci_pairing_active(hci_connection)) return;
440     hci_connection->authentication_flags &= ~AUTH_FLAG_PAIRING_ACTIVE_MASK;
441 #ifdef ENABLE_CLASSIC_PAIRING_OOB
442     hci_connection->classic_oob_c_192 = NULL;
443     hci_connection->classic_oob_r_192 = NULL;
444     hci_connection->classic_oob_c_256 = NULL;
445     hci_connection->classic_oob_r_256 = NULL;
446 #endif
447     log_info("pairing complete, status %02x", status);
448 
449     uint8_t event[12];
450     event[0] = GAP_EVENT_PAIRING_COMPLETE;
451     event[1] = 9;
452     little_endian_store_16(event, 2, (uint16_t) hci_connection->con_handle);
453     reverse_bd_addr(hci_connection->address, &event[4]);
454     event[10] = status;
455     hci_emit_event(event, sizeof(event), 1);
456 }
457 
458 bool hci_authentication_active_for_handle(hci_con_handle_t handle){
459     hci_connection_t * conn = hci_connection_for_handle(handle);
460     if (!conn) return false;
461     return hci_pairing_active(conn);
462 }
463 
464 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
465     if (!hci_stack->link_key_db) return;
466     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
467     hci_stack->link_key_db->delete_link_key(addr);
468 }
469 
470 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
471     if (!hci_stack->link_key_db) return;
472     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
473     hci_stack->link_key_db->put_link_key(addr, link_key, type);
474 }
475 
476 bool gap_get_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t * type){
477 	if (!hci_stack->link_key_db) return false;
478 	int result = hci_stack->link_key_db->get_link_key(addr, link_key, type) != 0;
479 	log_info("link key for %s available %u, type %u", bd_addr_to_str(addr), result, (int) *type);
480 	return result;
481 }
482 
483 void gap_delete_all_link_keys(void){
484     bd_addr_t  addr;
485     link_key_t link_key;
486     link_key_type_t type;
487     btstack_link_key_iterator_t it;
488     int ok = gap_link_key_iterator_init(&it);
489     if (!ok) {
490         log_error("could not initialize iterator");
491         return;
492     }
493     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
494         gap_drop_link_key_for_bd_addr(addr);
495     }
496     gap_link_key_iterator_done(&it);
497 }
498 
499 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
500     if (!hci_stack->link_key_db) return 0;
501     if (!hci_stack->link_key_db->iterator_init) return 0;
502     return hci_stack->link_key_db->iterator_init(it);
503 }
504 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){
505     if (!hci_stack->link_key_db) return 0;
506     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
507 }
508 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
509     if (!hci_stack->link_key_db) return;
510     hci_stack->link_key_db->iterator_done(it);
511 }
512 #endif
513 
514 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
515     switch (address_type){
516         case BD_ADDR_TYPE_LE_PUBLIC:
517         case BD_ADDR_TYPE_LE_RANDOM:
518         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
519         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
520             return true;
521         default:
522             return false;
523     }
524 }
525 
526 static int hci_is_le_connection(hci_connection_t * connection){
527     return hci_is_le_connection_type(connection->address_type);
528 }
529 
530 /**
531  * count connections
532  */
533 static int nr_hci_connections(void){
534     int count = 0;
535     btstack_linked_item_t *it;
536     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
537         count++;
538     }
539     return count;
540 }
541 
542 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
543 
544     unsigned int num_packets_sent_classic = 0;
545     unsigned int num_packets_sent_le = 0;
546 
547     btstack_linked_item_t *it;
548     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
549         hci_connection_t * connection = (hci_connection_t *) it;
550         if (hci_is_le_connection(connection)){
551             num_packets_sent_le += connection->num_packets_sent;
552         }
553         if (connection->address_type == BD_ADDR_TYPE_ACL){
554             num_packets_sent_classic += connection->num_packets_sent;
555         }
556     }
557     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
558     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
559     int free_slots_le = 0;
560 
561     if (free_slots_classic < 0){
562         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);
563         return 0;
564     }
565 
566     if (hci_stack->le_acl_packets_total_num){
567         // if we have LE slots, they are used
568         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
569         if (free_slots_le < 0){
570             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);
571             return 0;
572         }
573     } else {
574         // otherwise, classic slots are used for LE, too
575         free_slots_classic -= num_packets_sent_le;
576         if (free_slots_classic < 0){
577             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);
578             return 0;
579         }
580     }
581 
582     switch (address_type){
583         case BD_ADDR_TYPE_UNKNOWN:
584             log_error("hci_number_free_acl_slots: unknown address type");
585             return 0;
586 
587         case BD_ADDR_TYPE_ACL:
588             return free_slots_classic;
589 
590         default:
591            if (hci_stack->le_acl_packets_total_num){
592                return free_slots_le;
593            }
594            return free_slots_classic;
595     }
596 }
597 
598 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
599     // get connection type
600     hci_connection_t * connection = hci_connection_for_handle(con_handle);
601     if (!connection){
602         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
603         return 0;
604     }
605     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
606 }
607 
608 #ifdef ENABLE_CLASSIC
609 static int hci_number_free_sco_slots(void){
610     unsigned int num_sco_packets_sent  = 0;
611     btstack_linked_item_t *it;
612     if (hci_stack->synchronous_flow_control_enabled){
613         // explicit flow control
614         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
615             hci_connection_t * connection = (hci_connection_t *) it;
616             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
617             num_sco_packets_sent += connection->num_packets_sent;
618         }
619         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
620             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
621             return 0;
622         }
623         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
624     } else {
625         // implicit flow control -- TODO
626         int num_ready = 0;
627         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
628             hci_connection_t * connection = (hci_connection_t *) it;
629             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
630             if (connection->sco_tx_ready == 0) continue;
631             num_ready++;
632         }
633         return num_ready;
634     }
635 }
636 #endif
637 
638 // only used to send HCI Host Number Completed Packets
639 static int hci_can_send_comand_packet_transport(void){
640     if (hci_stack->hci_packet_buffer_reserved) return 0;
641 
642     // check for async hci transport implementations
643     if (hci_stack->hci_transport->can_send_packet_now){
644         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
645             return 0;
646         }
647     }
648     return 1;
649 }
650 
651 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
652 bool hci_can_send_command_packet_now(void){
653     if (hci_can_send_comand_packet_transport() == 0) return false;
654     return hci_stack->num_cmd_packets > 0u;
655 }
656 
657 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
658     // check for async hci transport implementations
659     if (!hci_stack->hci_transport->can_send_packet_now) return true;
660     return hci_stack->hci_transport->can_send_packet_now(packet_type);
661 }
662 
663 static bool hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
664     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
665     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
666 }
667 
668 bool hci_can_send_acl_le_packet_now(void){
669     if (hci_stack->hci_packet_buffer_reserved) return false;
670     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
671 }
672 
673 bool hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
674     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return false;
675     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
676 }
677 
678 bool hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
679     if (hci_stack->hci_packet_buffer_reserved) return false;
680     return hci_can_send_prepared_acl_packet_now(con_handle);
681 }
682 
683 #ifdef ENABLE_CLASSIC
684 bool hci_can_send_acl_classic_packet_now(void){
685     if (hci_stack->hci_packet_buffer_reserved) return false;
686     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
687 }
688 
689 bool hci_can_send_prepared_sco_packet_now(void){
690     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return false;
691     if (hci_have_usb_transport()){
692         return hci_stack->sco_can_send_now;
693     } else {
694         return hci_number_free_sco_slots() > 0;
695     }
696 }
697 
698 bool hci_can_send_sco_packet_now(void){
699     if (hci_stack->hci_packet_buffer_reserved) return false;
700     return hci_can_send_prepared_sco_packet_now();
701 }
702 
703 void hci_request_sco_can_send_now_event(void){
704     hci_stack->sco_waiting_for_can_send_now = 1;
705     hci_notify_if_sco_can_send_now();
706 }
707 #endif
708 
709 // used for internal checks in l2cap.c
710 bool hci_is_packet_buffer_reserved(void){
711     return hci_stack->hci_packet_buffer_reserved;
712 }
713 
714 // reserves outgoing packet buffer. @returns 1 if successful
715 bool hci_reserve_packet_buffer(void){
716     if (hci_stack->hci_packet_buffer_reserved) {
717         log_error("hci_reserve_packet_buffer called but buffer already reserved");
718         return false;
719     }
720     hci_stack->hci_packet_buffer_reserved = true;
721     return true;
722 }
723 
724 void hci_release_packet_buffer(void){
725     hci_stack->hci_packet_buffer_reserved = false;
726 }
727 
728 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
729 static int hci_transport_synchronous(void){
730     return hci_stack->hci_transport->can_send_packet_now == NULL;
731 }
732 
733 static uint8_t hci_send_acl_packet_fragments(hci_connection_t *connection){
734 
735     // 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);
736 
737     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
738     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
739     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
740         max_acl_data_packet_length = hci_stack->le_data_packets_length;
741     }
742 
743 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
744     if (hci_is_le_connection(connection) && (connection->le_max_tx_octets < max_acl_data_packet_length)){
745         max_acl_data_packet_length = connection->le_max_tx_octets;
746     }
747 #endif
748 
749     log_debug("hci_send_acl_packet_fragments entered");
750 
751     uint8_t status = ERROR_CODE_SUCCESS;
752     // multiple packets could be send on a synchronous HCI transport
753     while (true){
754 
755         log_debug("hci_send_acl_packet_fragments loop entered");
756 
757         // get current data
758         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
759         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
760         bool more_fragments = false;
761 
762         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
763         if (current_acl_data_packet_length > max_acl_data_packet_length){
764             more_fragments = true;
765             current_acl_data_packet_length = max_acl_data_packet_length;
766         }
767 
768         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
769         if (acl_header_pos > 0u){
770             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
771             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
772             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
773         }
774 
775         // update header len
776         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
777 
778         // count packet
779         connection->num_packets_sent++;
780         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", (int) more_fragments);
781 
782         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
783         if (more_fragments){
784             // update start of next fragment to send
785             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
786         } else {
787             // done
788             hci_stack->acl_fragmentation_pos = 0;
789             hci_stack->acl_fragmentation_total_size = 0;
790         }
791 
792         // send packet
793         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
794         const int size = current_acl_data_packet_length + 4;
795         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
796         hci_stack->acl_fragmentation_tx_active = 1;
797         int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
798         if (err != 0){
799             // no error from HCI Transport expected
800             status = ERROR_CODE_HARDWARE_FAILURE;
801         }
802 
803         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", (int) more_fragments);
804 
805         // done yet?
806         if (!more_fragments) break;
807 
808         // can send more?
809         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return status;
810     }
811 
812     log_debug("hci_send_acl_packet_fragments loop over");
813 
814     // release buffer now for synchronous transport
815     if (hci_transport_synchronous()){
816         hci_stack->acl_fragmentation_tx_active = 0;
817         hci_release_packet_buffer();
818         hci_emit_transport_packet_sent();
819     }
820 
821     return status;
822 }
823 
824 // pre: caller has reserved the packet buffer
825 uint8_t hci_send_acl_packet_buffer(int size){
826     btstack_assert(hci_stack->hci_packet_buffer_reserved);
827 
828     uint8_t * packet = hci_stack->hci_packet_buffer;
829     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
830 
831     // check for free places on Bluetooth module
832     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
833         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
834         hci_release_packet_buffer();
835         hci_emit_transport_packet_sent();
836         return BTSTACK_ACL_BUFFERS_FULL;
837     }
838 
839     hci_connection_t *connection = hci_connection_for_handle( con_handle);
840     if (!connection) {
841         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
842         hci_release_packet_buffer();
843         hci_emit_transport_packet_sent();
844         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
845     }
846 
847 #ifdef ENABLE_CLASSIC
848     hci_connection_timestamp(connection);
849 #endif
850 
851     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
852 
853     // setup data
854     hci_stack->acl_fragmentation_total_size = size;
855     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
856 
857     return hci_send_acl_packet_fragments(connection);
858 }
859 
860 #ifdef ENABLE_CLASSIC
861 // pre: caller has reserved the packet buffer
862 uint8_t hci_send_sco_packet_buffer(int size){
863     btstack_assert(hci_stack->hci_packet_buffer_reserved);
864 
865     uint8_t * packet = hci_stack->hci_packet_buffer;
866 
867     // skip checks in loopback mode
868     if (!hci_stack->loopback_mode){
869         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
870 
871         // check for free places on Bluetooth module
872         if (!hci_can_send_prepared_sco_packet_now()) {
873             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
874             hci_release_packet_buffer();
875             hci_emit_transport_packet_sent();
876             return BTSTACK_ACL_BUFFERS_FULL;
877         }
878 
879         // track send packet in connection struct
880         hci_connection_t *connection = hci_connection_for_handle( con_handle);
881         if (!connection) {
882             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
883             hci_release_packet_buffer();
884             hci_emit_transport_packet_sent();
885             return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
886         }
887 
888         if (hci_have_usb_transport()){
889             // token used
890             hci_stack->sco_can_send_now = false;
891         } else {
892             if (hci_stack->synchronous_flow_control_enabled){
893                 connection->num_packets_sent++;
894             } else {
895                 connection->sco_tx_ready--;
896             }
897         }
898     }
899 
900     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
901 
902 #ifdef HAVE_SCO_TRANSPORT
903     hci_stack->sco_transport->send_packet(packet, size);
904     hci_release_packet_buffer();
905     hci_emit_transport_packet_sent();
906 
907     return 0;
908 #else
909     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
910     if (hci_transport_synchronous()){
911         hci_release_packet_buffer();
912         hci_emit_transport_packet_sent();
913     }
914 
915     if (err != 0){
916         return ERROR_CODE_HARDWARE_FAILURE;
917     }
918     return ERROR_CODE_SUCCESS;
919 #endif
920 }
921 #endif
922 
923 static void acl_handler(uint8_t *packet, uint16_t size){
924 
925     // get info
926     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
927     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
928     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
929     uint16_t acl_length         = READ_ACL_LENGTH(packet);
930 
931     // ignore non-registered handle
932     if (!conn){
933         log_error("acl_handler called with non-registered handle %u!" , con_handle);
934         return;
935     }
936 
937     // assert packet is complete
938     if ((acl_length + 4u) != size){
939         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
940         return;
941     }
942 
943 #ifdef ENABLE_CLASSIC
944     // update idle timestamp
945     hci_connection_timestamp(conn);
946 #endif
947 
948 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
949     hci_stack->host_completed_packets = 1;
950     conn->num_packets_completed++;
951 #endif
952 
953     // handle different packet types
954     switch (acl_flags & 0x03u) {
955 
956         case 0x01: // continuation fragment
957 
958             // sanity checks
959             if (conn->acl_recombination_pos == 0u) {
960                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
961                 return;
962             }
963             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
964                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
965                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
966                 conn->acl_recombination_pos = 0;
967                 return;
968             }
969 
970             // append fragment payload (header already stored)
971             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
972                          &packet[4], acl_length);
973             conn->acl_recombination_pos += acl_length;
974 
975             // forward complete L2CAP packet if complete.
976             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
977                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
978                 // reset recombination buffer
979                 conn->acl_recombination_length = 0;
980                 conn->acl_recombination_pos = 0;
981             }
982             break;
983 
984         case 0x02: { // first fragment
985 
986             // sanity check
987             if (conn->acl_recombination_pos) {
988                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
989                 conn->acl_recombination_pos = 0;
990             }
991 
992             // peek into L2CAP packet!
993             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
994 
995             // compare fragment size to L2CAP packet size
996             if (acl_length >= (l2cap_length + 4u)){
997                 // forward fragment as L2CAP packet
998                 hci_emit_acl_packet(packet, acl_length + 4u);
999             } else {
1000 
1001                 if (acl_length > HCI_ACL_BUFFER_SIZE){
1002                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
1003                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
1004                     return;
1005                 }
1006 
1007                 // store first fragment and tweak acl length for complete package
1008                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
1009                              packet, acl_length + 4u);
1010                 conn->acl_recombination_pos    = acl_length + 4u;
1011                 conn->acl_recombination_length = l2cap_length;
1012                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
1013             }
1014             break;
1015 
1016         }
1017         default:
1018             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
1019             return;
1020     }
1021 
1022     // execute main loop
1023     hci_run();
1024 }
1025 
1026 static void hci_connection_stop_timer(hci_connection_t * conn){
1027     btstack_run_loop_remove_timer(&conn->timeout);
1028 #ifdef ENABLE_CLASSIC
1029     btstack_run_loop_remove_timer(&conn->timeout_sco);
1030 #endif
1031 }
1032 
1033 static void hci_shutdown_connection(hci_connection_t *conn){
1034     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
1035 
1036 #ifdef ENABLE_CLASSIC
1037 #if defined(ENABLE_SCO_OVER_HCI) || defined(HAVE_SCO_TRANSPORT)
1038     bd_addr_type_t addr_type = conn->address_type;
1039 #endif
1040 #ifdef HAVE_SCO_TRANSPORT
1041     hci_con_handle_t con_handle = conn->con_handle;
1042 #endif
1043 #endif
1044 
1045     hci_connection_stop_timer(conn);
1046 
1047     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1048     btstack_memory_hci_connection_free( conn );
1049 
1050     // now it's gone
1051     hci_emit_nr_connections_changed();
1052 
1053 #ifdef ENABLE_CLASSIC
1054 #ifdef ENABLE_SCO_OVER_HCI
1055     // update SCO
1056     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->hci_transport != NULL) && (hci_stack->hci_transport->set_sco_config != NULL)){
1057         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
1058     }
1059 #endif
1060 #ifdef HAVE_SCO_TRANSPORT
1061     if ((addr_type == BD_ADDR_TYPE_SCO) && (hci_stack->sco_transport != NULL)){
1062         hci_stack->sco_transport->close(con_handle);
1063     }
1064 #endif
1065 #endif
1066 }
1067 
1068 #ifdef ENABLE_CLASSIC
1069 
1070 static const uint16_t packet_type_sizes[] = {
1071     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
1072     HCI_ACL_DH1_SIZE, 0, 0, 0,
1073     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
1074     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
1075 };
1076 static const uint8_t  packet_type_feature_requirement_bit[] = {
1077      0, // 3 slot packets
1078      1, // 5 slot packets
1079     25, // EDR 2 mpbs
1080     26, // EDR 3 mbps
1081     39, // 3 slot EDR packts
1082     40, // 5 slot EDR packet
1083 };
1084 static const uint16_t packet_type_feature_packet_mask[] = {
1085     0x0f00, // 3 slot packets
1086     0xf000, // 5 slot packets
1087     0x1102, // EDR 2 mpbs
1088     0x2204, // EDR 3 mbps
1089     0x0300, // 3 slot EDR packts
1090     0x3000, // 5 slot EDR packet
1091 };
1092 
1093 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
1094     // enable packet types based on size
1095     uint16_t packet_types = 0;
1096     unsigned int i;
1097     for (i=0;i<16;i++){
1098         if (packet_type_sizes[i] == 0) continue;
1099         if (packet_type_sizes[i] <= buffer_size){
1100             packet_types |= 1 << i;
1101         }
1102     }
1103     // disable packet types due to missing local supported features
1104     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1105         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1106         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1107         if (feature_set) continue;
1108         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1109         packet_types &= ~packet_type_feature_packet_mask[i];
1110     }
1111     // flip bits for "may not be used"
1112     packet_types ^= 0x3306;
1113     return packet_types;
1114 }
1115 
1116 uint16_t hci_usable_acl_packet_types(void){
1117     return hci_stack->packet_types;
1118 }
1119 #endif
1120 
1121 uint8_t* hci_get_outgoing_packet_buffer(void){
1122     // hci packet buffer is >= acl data packet length
1123     return hci_stack->hci_packet_buffer;
1124 }
1125 
1126 uint16_t hci_max_acl_data_packet_length(void){
1127     return hci_stack->acl_data_packet_length;
1128 }
1129 
1130 #ifdef ENABLE_CLASSIC
1131 bool hci_extended_sco_link_supported(void){
1132     // No. 31, byte 3, bit 7
1133     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1134 }
1135 #endif
1136 
1137 bool hci_non_flushable_packet_boundary_flag_supported(void){
1138     // No. 54, byte 6, bit 6
1139     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1140 }
1141 
1142 static int gap_ssp_supported(void){
1143     // No. 51, byte 6, bit 3
1144     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1145 }
1146 
1147 static int hci_classic_supported(void){
1148 #ifdef ENABLE_CLASSIC
1149     // No. 37, byte 4, bit 5, = No BR/EDR Support
1150     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1151 #else
1152     return 0;
1153 #endif
1154 }
1155 
1156 static int hci_le_supported(void){
1157 #ifdef ENABLE_BLE
1158     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1159     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1160 #else
1161     return 0;
1162 #endif
1163 }
1164 
1165 #ifdef ENABLE_BLE
1166 
1167 static void hci_get_own_address_for_addr_type(uint8_t own_addr_type, bd_addr_t own_addr){
1168     if (own_addr_type == BD_ADDR_TYPE_LE_PUBLIC){
1169         (void)memcpy(own_addr, hci_stack->local_bd_addr, 6);
1170     } else {
1171         (void)memcpy(own_addr, hci_stack->le_random_address, 6);
1172     }
1173 }
1174 
1175 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1176     *addr_type = hci_stack->le_own_addr_type;
1177     hci_get_own_address_for_addr_type(hci_stack->le_own_addr_type, addr);
1178 }
1179 
1180 #ifdef ENABLE_LE_PERIPHERAL
1181 void gap_le_get_own_advertisements_address(uint8_t * addr_type, bd_addr_t addr){
1182     *addr_type = hci_stack->le_advertisements_own_addr_type;
1183     hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, addr);
1184 };
1185 #endif
1186 
1187 #ifdef ENABLE_LE_CENTRAL
1188 
1189 /**
1190  * @brief Get own addr type and address used for LE connections (Central)
1191  */
1192 void gap_le_get_own_connection_address(uint8_t * addr_type, bd_addr_t addr){
1193     *addr_type = hci_stack->le_connection_own_addr_type;
1194     hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, addr);
1195 }
1196 
1197 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1198 
1199     int offset = 3;
1200     int num_reports = packet[offset];
1201     offset += 1;
1202 
1203     int i;
1204     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1205     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1206     for (i=0; (i<num_reports) && (offset < size);i++){
1207         // sanity checks on data_length:
1208         uint8_t data_length = packet[offset + 8];
1209         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1210         if ((offset + 9u + data_length + 1u) > size)    return;
1211         // setup event
1212         uint8_t event_size = 10u + data_length;
1213         int pos = 0;
1214         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1215         event[pos++] = event_size;
1216         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1217         offset += 8;
1218         pos += 8;
1219         event[pos++] = packet[offset + 1 + data_length]; // rssi
1220         event[pos++] = data_length;
1221         offset++;
1222         (void)memcpy(&event[pos], &packet[offset], data_length);
1223         pos +=    data_length;
1224         offset += data_length + 1u; // rssi
1225         hci_emit_event(event, pos, 1);
1226     }
1227 }
1228 #endif
1229 #endif
1230 
1231 #ifdef ENABLE_BLE
1232 #ifdef ENABLE_LE_PERIPHERAL
1233 static void hci_update_advertisements_enabled_for_current_roles(void){
1234     if (hci_stack->le_advertisements_enabled){
1235         // get number of active le slave connections
1236         int num_slave_connections = 0;
1237         btstack_linked_list_iterator_t it;
1238         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1239         while (btstack_linked_list_iterator_has_next(&it)){
1240             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1241             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1242             if (con->state != OPEN) continue;
1243             if (con->role  != HCI_ROLE_SLAVE) continue;
1244             if (!hci_is_le_connection(con)) continue;
1245             num_slave_connections++;
1246         }
1247         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1248         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1249     } else {
1250         hci_stack->le_advertisements_enabled_for_current_roles = false;
1251     }
1252 }
1253 #endif
1254 #endif
1255 
1256 #ifdef ENABLE_CLASSIC
1257 static void gap_run_set_local_name(void){
1258     hci_reserve_packet_buffer();
1259     uint8_t * packet = hci_stack->hci_packet_buffer;
1260     // construct HCI Command and send
1261     uint16_t opcode = hci_write_local_name.opcode;
1262     hci_stack->last_cmd_opcode = opcode;
1263     packet[0] = opcode & 0xff;
1264     packet[1] = opcode >> 8;
1265     packet[2] = DEVICE_NAME_LEN;
1266     memset(&packet[3], 0, DEVICE_NAME_LEN);
1267     uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1268     uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1269     // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1270     (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1271     // expand '00:00:00:00:00:00' in name with bd_addr
1272     btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1273     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1274 }
1275 
1276 static void gap_run_set_eir_data(void){
1277     hci_reserve_packet_buffer();
1278     uint8_t * packet = hci_stack->hci_packet_buffer;
1279     // construct HCI Command in-place and send
1280     uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1281     hci_stack->last_cmd_opcode = opcode;
1282     uint16_t offset = 0;
1283     packet[offset++] = opcode & 0xff;
1284     packet[offset++] = opcode >> 8;
1285     packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1286     packet[offset++] = 0;  // FEC not required
1287     memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1288     if (hci_stack->eir_data){
1289         // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1290         ad_context_t context;
1291         for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1292             uint8_t data_type   = ad_iterator_get_data_type(&context);
1293             uint8_t size        = ad_iterator_get_data_len(&context);
1294             const uint8_t *data = ad_iterator_get_data(&context);
1295             // copy item
1296             packet[offset++] = size + 1;
1297             packet[offset++] = data_type;
1298             memcpy(&packet[offset], data, size);
1299             // update name item
1300             if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1301                 btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1302             }
1303             offset += size;
1304         }
1305     } else {
1306         uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1307         uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1308         packet[offset++] = bytes_to_copy + 1;
1309         packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1310         (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1311         // expand '00:00:00:00:00:00' in name with bd_addr
1312         btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1313     }
1314     hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1315 }
1316 
1317 static void hci_run_gap_tasks_classic(void){
1318     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
1319         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
1320         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1321         return;
1322     }
1323     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
1324         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
1325         gap_run_set_local_name();
1326         return;
1327     }
1328     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
1329         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
1330         gap_run_set_eir_data();
1331         return;
1332     }
1333     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
1334         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
1335         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1336         return;
1337     }
1338     // write page scan activity
1339     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY) != 0) {
1340         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
1341         hci_send_cmd(&hci_write_page_scan_activity, hci_stack->new_page_scan_interval, hci_stack->new_page_scan_window);
1342         return;
1343     }
1344     // write page scan type
1345     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_PAGE_SCAN_TYPE) != 0) {
1346         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_PAGE_SCAN_TYPE;
1347         hci_send_cmd(&hci_write_page_scan_type, hci_stack->new_page_scan_type);
1348         return;
1349     }
1350     // send scan enable
1351     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
1352         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
1353         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1354         return;
1355     }
1356 }
1357 #endif
1358 
1359 #ifndef HAVE_HOST_CONTROLLER_API
1360 
1361 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1362     if (!hci_stack->config) return 0;
1363     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1364     // Limit baud rate for Broadcom chipsets to 3 mbps
1365     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1366         baud_rate = 3000000;
1367     }
1368     return baud_rate;
1369 }
1370 
1371 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1372     UNUSED(ds);
1373 
1374     switch (hci_stack->substate){
1375         case HCI_INIT_W4_SEND_RESET:
1376             log_info("Resend HCI Reset");
1377             hci_stack->substate = HCI_INIT_SEND_RESET;
1378             hci_stack->num_cmd_packets = 1;
1379             hci_run();
1380             break;
1381         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1382             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1383             if (hci_stack->hci_transport->reset_link){
1384                 hci_stack->hci_transport->reset_link();
1385             }
1386 
1387             /* fall through */
1388 
1389         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1390             log_info("Resend HCI Reset - CSR Warm Boot");
1391             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1392             hci_stack->num_cmd_packets = 1;
1393             hci_run();
1394             break;
1395         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1396             if (hci_stack->hci_transport->set_baudrate){
1397                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1398                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1399                 hci_stack->hci_transport->set_baudrate(baud_rate);
1400             }
1401             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1402             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1403                 if (hci_stack->hci_transport->reset_link){
1404                     log_info("Link Reset");
1405                     hci_stack->hci_transport->reset_link();
1406                 }
1407                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1408                 hci_run();
1409             }
1410             break;
1411         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1412             // otherwise continue
1413             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1414             hci_send_cmd(&hci_read_local_supported_commands);
1415             break;
1416         default:
1417             break;
1418     }
1419 }
1420 #endif
1421 
1422 static void hci_initializing_next_state(void){
1423     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1424 }
1425 
1426 static void hci_init_done(void){
1427     // done. tell the app
1428     log_info("hci_init_done -> HCI_STATE_WORKING");
1429     hci_stack->state = HCI_STATE_WORKING;
1430     hci_emit_state();
1431 }
1432 
1433 // assumption: hci_can_send_command_packet_now() == true
1434 static void hci_initializing_run(void){
1435     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1436 
1437     bool need_baud_change = false;
1438 
1439 #ifndef HAVE_HOST_CONTROLLER_API
1440     need_baud_change = hci_stack->config
1441             && hci_stack->chipset
1442             && hci_stack->chipset->set_baudrate_command
1443             && hci_stack->hci_transport->set_baudrate
1444             && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1445 #endif
1446 
1447     switch (hci_stack->substate){
1448         case HCI_INIT_SEND_RESET:
1449             hci_state_reset();
1450 
1451 #ifndef HAVE_HOST_CONTROLLER_API
1452             // prepare reset if command complete not received in 100ms
1453             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1454             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1455             btstack_run_loop_add_timer(&hci_stack->timeout);
1456 #endif
1457             // send command
1458             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1459             hci_send_cmd(&hci_reset);
1460             break;
1461         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1462             hci_send_cmd(&hci_read_local_version_information);
1463             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1464             break;
1465         case HCI_INIT_SEND_READ_LOCAL_NAME:
1466             hci_send_cmd(&hci_read_local_name);
1467             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1468             break;
1469 
1470 #ifndef HAVE_HOST_CONTROLLER_API
1471         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1472             hci_state_reset();
1473             // prepare reset if command complete not received in 100ms
1474             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1475             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1476             btstack_run_loop_add_timer(&hci_stack->timeout);
1477             // send command
1478             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1479             hci_send_cmd(&hci_reset);
1480             break;
1481         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1482             hci_state_reset();
1483             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1484             hci_send_cmd(&hci_reset);
1485             break;
1486         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1487             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1488             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1489             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1490             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1491             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1492             break;
1493         }
1494         case HCI_INIT_SET_BD_ADDR:
1495             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1496             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1497             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1498             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1499             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1500             break;
1501         case HCI_INIT_SEND_BAUD_CHANGE:
1502             if (need_baud_change) {
1503                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1504                 hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1505                 hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1506                 hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1507                 hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1508                 // STLC25000D: baudrate change happens within 0.5 s after command was send,
1509                 // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1510                 if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1511                     btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1512                     btstack_run_loop_add_timer(&hci_stack->timeout);
1513                }
1514                break;
1515             }
1516 
1517             /* fall through */
1518 
1519         case HCI_INIT_CUSTOM_INIT:
1520             // Custom initialization
1521             if (hci_stack->chipset && hci_stack->chipset->next_command){
1522                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1523                 bool send_cmd = false;
1524                 switch (hci_stack->chipset_result){
1525                     case BTSTACK_CHIPSET_VALID_COMMAND:
1526                         send_cmd = true;
1527                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1528                         break;
1529                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1530                         send_cmd = true;
1531                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1532                         log_info("CSR Warm Boot");
1533                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1534                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1535                         btstack_run_loop_add_timer(&hci_stack->timeout);
1536                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1537                             && hci_stack->config
1538                             && hci_stack->chipset
1539                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1540                             && hci_stack->hci_transport->set_baudrate
1541                             && hci_transport_uart_get_main_baud_rate()){
1542                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1543                         } else {
1544                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1545                         }
1546                         break;
1547                     default:
1548                         break;
1549                 }
1550 
1551                 if (send_cmd){
1552                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1553                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1554                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1555                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1556                     break;
1557                 }
1558                 log_info("Init script done");
1559 
1560                 // Init script download on Broadcom chipsets causes:
1561                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1562                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1563                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1564 
1565                     // - baud rate to reset, restore UART baud rate if needed
1566                     if (need_baud_change) {
1567                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1568                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1569                         hci_stack->hci_transport->set_baudrate(baud_rate);
1570                     }
1571 
1572                     uint16_t bcm_delay_ms = 300;
1573                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1574                     //   -> Work around: wait here.
1575                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1576                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1577                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1578                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1579                     btstack_run_loop_add_timer(&hci_stack->timeout);
1580                     break;
1581                 }
1582             }
1583             /* fall through */
1584 #endif
1585 
1586         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1587             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1588             hci_send_cmd(&hci_read_local_supported_commands);
1589             break;
1590         case HCI_INIT_READ_BD_ADDR:
1591             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1592             hci_send_cmd(&hci_read_bd_addr);
1593             break;
1594         case HCI_INIT_READ_BUFFER_SIZE:
1595             // only read buffer size if supported
1596             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1597                 hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1598                 hci_send_cmd(&hci_read_buffer_size);
1599                 break;
1600             }
1601             /* fall through */
1602 
1603         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1604             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1605             hci_send_cmd(&hci_read_local_supported_features);
1606             break;
1607 
1608 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1609         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1610             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1611             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1612             break;
1613         case HCI_INIT_HOST_BUFFER_SIZE:
1614             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1615             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1616                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1617             break;
1618 #endif
1619 
1620         case HCI_INIT_SET_EVENT_MASK:
1621             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1622             if (hci_le_supported()){
1623                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1624             } else {
1625                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1626                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1627             }
1628             break;
1629 
1630 #ifdef ENABLE_CLASSIC
1631         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1632             if (hci_classic_supported() && gap_ssp_supported()){
1633                 hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1634                 hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1635                 break;
1636             }
1637             /* fall through */
1638 
1639         case HCI_INIT_WRITE_INQUIRY_MODE:
1640             if (hci_classic_supported()){
1641                 hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1642                 hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1643                 break;
1644             }
1645             /* fall through */
1646 
1647         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1648             // skip write secure connections host support if not supported or disabled
1649             if (hci_classic_supported() && hci_stack->secure_connections_enable && (hci_stack->local_supported_commands[1u] & 0x02u) != 0u) {
1650                 hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1651                 hci_stack->secure_connections_active = true;
1652                 hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1653                 break;
1654             }
1655             /* fall through */
1656 
1657         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1658             if (hci_classic_supported()){
1659                 hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1660                 hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1661                 break;
1662             }
1663             /* fall through */
1664 
1665 #ifdef ENABLE_SCO_OVER_HCI
1666         // only sent if ENABLE_SCO_OVER_HCI is defined
1667         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1668             // skip write synchronous flow control if not supported
1669             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x04) != 0)){
1670                 hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1671                 hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1672                 break;
1673             }
1674             /* fall through */
1675 
1676         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1677             // skip write default erroneous data reporting if not supported
1678             if (hci_classic_supported() && ((hci_stack->local_supported_commands[0] & 0x08) != 0)){
1679                 hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1680                 hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1681                 break;
1682             }
1683             /* fall through */
1684 #endif
1685 
1686 #if defined(ENABLE_SCO_OVER_HCI) || defined(ENABLE_SCO_OVER_PCM)
1687         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1688         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1689             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1690                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1691 #ifdef ENABLE_SCO_OVER_HCI
1692                 log_info("BCM: Route SCO data via HCI transport");
1693                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1694 #endif
1695 #ifdef ENABLE_SCO_OVER_PCM
1696                 log_info("BCM: Route SCO data via PCM interface");
1697 #ifdef ENABLE_BCM_PCM_WBS
1698                 // 512 kHz bit clock for 2 channels x 16 bit x 16 kHz
1699                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1700 #else
1701                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1702                 hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1703 #endif
1704 #endif
1705                 break;
1706             }
1707             /* fall through */
1708 #endif
1709 
1710 #ifdef ENABLE_SCO_OVER_PCM
1711         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1712             if (hci_classic_supported() && (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)){
1713                 hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1714                 log_info("BCM: Config PCM interface for I2S");
1715 #ifdef ENABLE_BCM_PCM_WBS
1716                 // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1717                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1718 #else
1719                 // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1720                 hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1721 #endif
1722                 break;
1723             }
1724             /* fall through */
1725 #endif
1726 #endif
1727 
1728 #ifdef ENABLE_BLE
1729         // LE INIT
1730         case HCI_INIT_LE_READ_BUFFER_SIZE:
1731             if (hci_le_supported()){
1732                 hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1733                 hci_send_cmd(&hci_le_read_buffer_size);
1734                 break;
1735             }
1736             /* fall through */
1737 
1738         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1739             // skip write le host if not supported (e.g. on LE only EM9301)
1740             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x02u) != 0)){
1741                 // LE Supported Host = 1, Simultaneous Host = 0
1742                 hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1743                 hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1744                 break;
1745             }
1746             /* fall through */
1747 
1748         case HCI_INIT_LE_SET_EVENT_MASK:
1749             if (hci_le_supported()){
1750                 hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1751                 hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1752                 break;
1753             }
1754             /* fall through */
1755 
1756 #endif
1757 
1758 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1759         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1760             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1761                 hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1762                 hci_send_cmd(&hci_le_read_maximum_data_length);
1763                 break;
1764             }
1765             /* fall through */
1766 
1767         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1768             if (hci_le_supported() && ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u)){
1769                 hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1770                 hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1771                 break;
1772             }
1773             /* fall through */
1774 #endif
1775 
1776 #ifdef ENABLE_LE_CENTRAL
1777         case HCI_INIT_READ_WHITE_LIST_SIZE:
1778             if (hci_le_supported()){
1779                 hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1780                 hci_send_cmd(&hci_le_read_white_list_size);
1781                 break;
1782             }
1783             /* fall through */
1784 
1785         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1786             if (hci_le_supported()){
1787                 hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1788                 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);
1789                 break;
1790             }
1791             /* fall through */
1792 #endif
1793 
1794         case HCI_INIT_DONE:
1795             hci_stack->substate = HCI_INIT_DONE;
1796 #ifdef ENABLE_CLASSIC
1797             // init sequence complete, check if GAP Tasks are completed
1798             if (hci_stack->gap_tasks != 0) {
1799                 hci_run_gap_tasks_classic();
1800                 break;
1801             }
1802 #endif
1803             hci_init_done();
1804             break;
1805 
1806         default:
1807             return;
1808     }
1809 }
1810 
1811 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1812     bool command_completed = false;
1813     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1814         uint16_t opcode = little_endian_read_16(packet,3);
1815         if (opcode == hci_stack->last_cmd_opcode){
1816             command_completed = true;
1817             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1818         } else {
1819             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1820         }
1821     }
1822 
1823     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1824         uint8_t  status = packet[2];
1825         uint16_t opcode = little_endian_read_16(packet,4);
1826         if (opcode == hci_stack->last_cmd_opcode){
1827             if (status){
1828                 command_completed = true;
1829                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1830             } else {
1831                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1832             }
1833         } else {
1834             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1835         }
1836     }
1837 #ifndef HAVE_HOST_CONTROLLER_API
1838     // Vendor == CSR
1839     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1840         // TODO: track actual command
1841         command_completed = true;
1842     }
1843 
1844     // Vendor == Toshiba
1845     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1846         // TODO: track actual command
1847         command_completed = true;
1848         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1849         hci_stack->num_cmd_packets = 1;
1850     }
1851 #endif
1852 
1853     return command_completed;
1854 }
1855 
1856 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1857 
1858     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1859 
1860     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1861 
1862 #ifndef HAVE_HOST_CONTROLLER_API
1863 
1864     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1865     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1866     //
1867     // HCI Reset
1868     // Timeout 100 ms
1869     // HCI Reset
1870     // Command Complete Reset
1871     // HCI Read Local Version Information
1872     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1873     // hang...
1874     //
1875     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1876     if (!command_completed
1877             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1878             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1879 
1880         uint16_t opcode = little_endian_read_16(packet,3);
1881         if (opcode == hci_reset.opcode){
1882             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1883             return;
1884         }
1885     }
1886 
1887     // CSR & H5
1888     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1889     if (!command_completed
1890             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1891             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1892 
1893         uint16_t opcode = little_endian_read_16(packet,3);
1894         if (opcode == hci_reset.opcode){
1895             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1896             return;
1897         }
1898     }
1899 
1900     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1901     // fix: Correct substate and behave as command below
1902     if (command_completed){
1903         switch (hci_stack->substate){
1904             case HCI_INIT_SEND_RESET:
1905                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1906                 break;
1907             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1908                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1909                 break;
1910             default:
1911                 break;
1912         }
1913     }
1914 
1915 #endif
1916 
1917     if (!command_completed) return;
1918 
1919     bool need_baud_change = false;
1920     bool need_addr_change = false;
1921 
1922 #ifndef HAVE_HOST_CONTROLLER_API
1923     need_baud_change = hci_stack->config
1924                         && hci_stack->chipset
1925                         && hci_stack->chipset->set_baudrate_command
1926                         && hci_stack->hci_transport->set_baudrate
1927                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1928 
1929     need_addr_change = hci_stack->custom_bd_addr_set
1930                         && hci_stack->chipset
1931                         && hci_stack->chipset->set_bd_addr_command;
1932 #endif
1933 
1934     switch(hci_stack->substate){
1935 
1936 #ifndef HAVE_HOST_CONTROLLER_API
1937         case HCI_INIT_SEND_RESET:
1938             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1939             // fix: just correct substate and behave as command below
1940 
1941             /* fall through */
1942 #endif
1943 
1944         case HCI_INIT_W4_SEND_RESET:
1945             btstack_run_loop_remove_timer(&hci_stack->timeout);
1946             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1947             return;
1948 
1949 #ifndef HAVE_HOST_CONTROLLER_API
1950         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1951             // for STLC2500D, baud rate change already happened.
1952             // for others, baud rate gets changed now
1953             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1954                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1955                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1956                 hci_stack->hci_transport->set_baudrate(baud_rate);
1957             }
1958             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1959             return;
1960         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1961             btstack_run_loop_remove_timer(&hci_stack->timeout);
1962             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1963             return;
1964         case HCI_INIT_W4_CUSTOM_INIT:
1965             // repeat custom init
1966             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1967             return;
1968 #endif
1969 
1970         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1971             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1972               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1973                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1974                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1975                 return;
1976             }
1977             if (need_addr_change){
1978                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1979                 return;
1980             }
1981             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1982             return;
1983 #ifndef HAVE_HOST_CONTROLLER_API
1984         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1985             if (need_baud_change){
1986                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1987                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1988                 hci_stack->hci_transport->set_baudrate(baud_rate);
1989             }
1990             if (need_addr_change){
1991                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1992                 return;
1993             }
1994             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1995             return;
1996         case HCI_INIT_W4_SET_BD_ADDR:
1997             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1998             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1999             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
2000                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
2001                 return;
2002             }
2003             // skipping st warm boot
2004             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2005             return;
2006         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
2007             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
2008             return;
2009 #endif
2010 
2011         case HCI_INIT_DONE:
2012             // set state if we came here by fall through
2013             hci_stack->substate = HCI_INIT_DONE;
2014             return;
2015 
2016         default:
2017             break;
2018     }
2019     hci_initializing_next_state();
2020 }
2021 
2022 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2023     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2024     bd_addr_t bd_address;
2025     (void)memcpy(&bd_address, conn->address, 6);
2026 
2027 #ifdef ENABLE_CLASSIC
2028     // cache needed data
2029     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2030 #endif
2031 
2032     // connection failed, remove entry
2033     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2034     btstack_memory_hci_connection_free( conn );
2035 
2036 #ifdef ENABLE_CLASSIC
2037     // notify client if dedicated bonding
2038     if (notify_dedicated_bonding_failed){
2039         log_info("hci notify_dedicated_bonding_failed");
2040         hci_emit_dedicated_bonding_result(bd_address, status);
2041     }
2042 
2043     // if authentication error, also delete link key
2044     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2045         gap_drop_link_key_for_bd_addr(bd_address);
2046     }
2047 #else
2048     UNUSED(status);
2049 #endif
2050 }
2051 
2052 #ifdef ENABLE_CLASSIC
2053 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2054     // SSP Controller
2055     if (features[6] & (1 << 3)){
2056         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2057     }
2058     // eSCO
2059     if (features[3] & (1<<7)){
2060         conn->remote_supported_features[0] |= 1;
2061     }
2062     // Extended features
2063     if (features[7] & (1<<7)){
2064         conn->remote_supported_features[0] |= 2;
2065     }
2066 }
2067 
2068 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2069     // SSP Host
2070     if (features[0] & (1 << 0)){
2071         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2072     }
2073     // SC Host
2074     if (features[0] & (1 << 3)){
2075         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2076     }
2077 }
2078 
2079 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2080     // SC Controller
2081     if (features[1] & (1 << 0)){
2082         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2083     }
2084 }
2085 
2086 static void hci_handle_remote_features_received(hci_connection_t * conn){
2087     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2088     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2089     if (conn->bonding_flags & BONDING_DEDICATED){
2090         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2091     }
2092 }
2093 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2094     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2095     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2096 }
2097 
2098 #endif
2099 
2100 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2101     // handle BT initialization
2102     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2103         hci_initializing_event_handler(packet, size);
2104     }
2105 
2106     // help with BT sleep
2107     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2108         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2109         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2110         hci_initializing_next_state();
2111     }
2112 }
2113 
2114 #ifdef ENABLE_CLASSIC
2115 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2116     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2117     conn->encryption_key_size = encryption_key_size;
2118 
2119     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2120         conn->requested_security_level = LEVEL_0;
2121         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2122         return;
2123     }
2124 
2125     // Request Authentication if not already done
2126     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2127     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2128 }
2129 #endif
2130 
2131 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2132     UNUSED(size);
2133 
2134     uint16_t manufacturer;
2135 #ifdef ENABLE_CLASSIC
2136     hci_con_handle_t handle;
2137     hci_connection_t * conn;
2138     uint8_t status;
2139 #endif
2140     // get num cmd packets - limit to 1 to reduce complexity
2141     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2142 
2143     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2144     switch (opcode){
2145         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2146             if (packet[5]) break;
2147             // terminate, name 248 chars
2148             packet[6+248] = 0;
2149             log_info("local name: %s", &packet[6]);
2150             break;
2151         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2152             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2153             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2154                 uint16_t acl_len = little_endian_read_16(packet, 6);
2155                 uint16_t sco_len = packet[8];
2156 
2157                 // determine usable ACL/SCO payload size
2158                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2159                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2160 
2161                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2162                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2163 
2164                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2165                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2166                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2167             }
2168             break;
2169         case HCI_OPCODE_HCI_READ_RSSI:
2170             if (packet[5] == ERROR_CODE_SUCCESS){
2171                 uint8_t event[5];
2172                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2173                 event[1] = 3;
2174                 (void)memcpy(&event[2], &packet[6], 3);
2175                 hci_emit_event(event, sizeof(event), 1);
2176             }
2177             break;
2178 #ifdef ENABLE_BLE
2179         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2180             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2181             hci_stack->le_acl_packets_total_num = packet[8];
2182             // determine usable ACL payload size
2183             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2184                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2185             }
2186             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2187             break;
2188 #endif
2189 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2190         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2191             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2192             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2193             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);
2194             break;
2195 #endif
2196 #ifdef ENABLE_LE_CENTRAL
2197         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2198             hci_stack->le_whitelist_capacity = packet[6];
2199             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2200             break;
2201 #endif
2202         case HCI_OPCODE_HCI_READ_BD_ADDR:
2203             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2204             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));
2205 #ifdef ENABLE_CLASSIC
2206             if (hci_stack->link_key_db){
2207                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2208             }
2209 #endif
2210             break;
2211 #ifdef ENABLE_CLASSIC
2212         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2213             hci_emit_discoverable_enabled(hci_stack->discoverable);
2214             break;
2215         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2216             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2217                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2218                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2219                 hci_emit_event(event, sizeof(event), 1);
2220             }
2221             break;
2222 #endif
2223         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2224             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2225 
2226 #ifdef ENABLE_CLASSIC
2227             // determine usable ACL packet types based on host buffer size and supported features
2228             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2229             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2230 #endif
2231             // Classic/LE
2232             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2233             break;
2234         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2235             manufacturer = little_endian_read_16(packet, 10);
2236             // map Cypress to Broadcom
2237             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2238                 log_info("Treat Cypress as Broadcom");
2239                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2240                 little_endian_store_16(packet, 10, manufacturer);
2241             }
2242             hci_stack->manufacturer = manufacturer;
2243             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2244             break;
2245         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2246             hci_stack->local_supported_commands[0] =
2247                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2248                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2249                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2250                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2251                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2252                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2253                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2254                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2255             hci_stack->local_supported_commands[1] =
2256                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2257                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2258                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2259                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2260                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2261             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2262             break;
2263 #ifdef ENABLE_CLASSIC
2264         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2265             if (packet[5]) return;
2266             hci_stack->synchronous_flow_control_enabled = 1;
2267             break;
2268         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2269             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2270             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2271             conn   = hci_connection_for_handle(handle);
2272             if (conn != NULL) {
2273                 uint8_t key_size = 0;
2274                 if (status == 0){
2275                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2276                     log_info("Handle %04x key Size: %u", handle, key_size);
2277                 } else {
2278                     key_size = 1;
2279                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2280                 }
2281                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2282             }
2283             break;
2284         // assert pairing complete event is emitted.
2285         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2286         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2287         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2288         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2289             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2290             // lookup connection by gap pairing addr
2291             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2292             if (conn == NULL) break;
2293             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2294             break;
2295 
2296 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2297         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2298         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2299             uint8_t event[67];
2300             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2301             event[1] = 65;
2302             (void)memset(&event[2], 0, 65);
2303             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2304                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2305                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2306                     event[2] = 3;
2307                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2308                 } else {
2309                     event[2] = 1;
2310                 }
2311             }
2312             hci_emit_event(event, sizeof(event), 0);
2313             break;
2314         }
2315 
2316         // note: only needed if user does not provide OOB data
2317         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2318             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2319             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2320             if (conn == NULL) break;
2321             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2322             break;
2323 #endif
2324 #endif
2325         default:
2326             break;
2327     }
2328 }
2329 
2330 #ifdef ENABLE_BLE
2331 static void event_handle_le_connection_complete(const uint8_t * packet){
2332 	bd_addr_t addr;
2333 	bd_addr_type_t addr_type;
2334 	hci_connection_t * conn;
2335 
2336 	// Connection management
2337 	reverse_bd_addr(&packet[8], addr);
2338 	addr_type = (bd_addr_type_t)packet[7];
2339 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2340 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2341 
2342 #ifdef ENABLE_LE_CENTRAL
2343 	// handle error: error is reported only to the initiator -> outgoing connection
2344 	if (packet[3]){
2345 
2346 		// handle cancelled outgoing connection
2347 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2348 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2349 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2350 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2351 		    // reset state
2352             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2353             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2354 			// get outgoing connection conn struct for direct connect
2355 			conn = gap_get_outgoing_connection();
2356 		}
2357 
2358 		// outgoing le connection establishment is done
2359 		if (conn){
2360 			// remove entry
2361 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2362 			btstack_memory_hci_connection_free( conn );
2363 		}
2364 		return;
2365 	}
2366 #endif
2367 
2368 	// on success, both hosts receive connection complete event
2369 	if (packet[6] == HCI_ROLE_MASTER){
2370 #ifdef ENABLE_LE_CENTRAL
2371 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2372 		// note: no hci_connection_t object exists yet for connect with whitelist
2373 		if (hci_is_le_connection_type(addr_type)){
2374 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2375 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2376 		}
2377 #endif
2378 	} else {
2379 #ifdef ENABLE_LE_PERIPHERAL
2380 		// if we're slave, it was an incoming connection, advertisements have stopped
2381 		hci_stack->le_advertisements_active = false;
2382 #endif
2383 	}
2384 
2385 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2386 	if (!conn){
2387 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2388 	}
2389 
2390 	// no memory, sorry.
2391 	if (!conn){
2392 		return;
2393 	}
2394 
2395 	conn->state = OPEN;
2396 	conn->role  = packet[6];
2397 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2398 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2399 
2400 #ifdef ENABLE_LE_PERIPHERAL
2401 	if (packet[6] == HCI_ROLE_SLAVE){
2402 		hci_update_advertisements_enabled_for_current_roles();
2403 	}
2404 #endif
2405 
2406     // init unenhanced att bearer mtu
2407     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2408     conn->att_connection.mtu_exchanged = false;
2409 
2410     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2411 
2412 	// restart timer
2413 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2414 	// btstack_run_loop_add_timer(&conn->timeout);
2415 
2416 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2417 
2418 	hci_emit_nr_connections_changed();
2419 }
2420 #endif
2421 
2422 #ifdef ENABLE_CLASSIC
2423 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){
2424     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2425     // LEVEL_4 is tested by l2cap
2426     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2427     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2428     if (level >= LEVEL_3){
2429         // MITM not possible without keyboard or display
2430         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2431         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2432 
2433         // MITM possible if one side has keyboard and the other has keyboard or display
2434         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2435         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2436 
2437         // MITM not possible if one side has only display and other side has no keyboard
2438         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2439         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2440     }
2441     // LEVEL 2 requires SSP, which is a given
2442     return true;
2443 }
2444 
2445 static bool btstack_is_null(uint8_t * data, uint16_t size){
2446     uint16_t i;
2447     for (i=0; i < size ; i++){
2448         if (data[i] != 0) {
2449             return false;
2450         }
2451     }
2452     return true;
2453 }
2454 
2455 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2456     // get requested security level
2457     gap_security_level_t requested_security_level = conn->requested_security_level;
2458     if (hci_stack->gap_secure_connections_only_mode){
2459         requested_security_level = LEVEL_4;
2460     }
2461 
2462     // assess security: LEVEL 4 requires SC
2463     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2464     if ((requested_security_level == LEVEL_4) &&
2465         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2466         !hci_remote_sc_enabled(conn)){
2467         log_info("Level 4 required, but SC not supported -> abort");
2468         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2469         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2470         return;
2471     }
2472 
2473     // assess security based on io capabilities
2474     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2475         // responder: fully validate io caps of both sides as well as OOB data
2476         bool security_possible = false;
2477         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2478 
2479 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2480         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2481         // so we merge the OOB data availability
2482         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2483         if (conn->classic_oob_c_192 != NULL){
2484             have_oob_data |= 1;
2485         }
2486         if (conn->classic_oob_c_256 != NULL){
2487             have_oob_data |= 2;
2488         }
2489         // for up to Level 3, either P-192 as well as P-256 will do
2490         // if we don't support SC, then a) conn->classic_oob_c_256 will be NULL and b) remote should not report P-256 available
2491         // if remote does not SC, we should not receive P-256 data either
2492         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2493             security_possible = true;
2494         }
2495         // for Level 4, P-256 is needed
2496         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2497             security_possible = true;
2498         }
2499 #endif
2500 
2501         if (security_possible == false){
2502             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2503             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2504             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2505             return;
2506         }
2507     } else {
2508         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2509 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2510 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2511         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2512             log_info("Level 3+ required, but no input/output -> abort");
2513             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2514             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2515             return;
2516         }
2517 #endif
2518 #endif
2519     }
2520 
2521 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2522     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2523         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2524     } else {
2525         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2526     }
2527 #endif
2528 }
2529 
2530 #endif
2531 
2532 static void event_handler(uint8_t *packet, uint16_t size){
2533 
2534     uint16_t event_length = packet[1];
2535 
2536     // assert packet is complete
2537     if (size != (event_length + 2u)){
2538         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2539         return;
2540     }
2541 
2542     bd_addr_type_t addr_type;
2543     hci_con_handle_t handle;
2544     hci_connection_t * conn;
2545     int i;
2546     int create_connection_cmd;
2547 
2548 #ifdef ENABLE_CLASSIC
2549     hci_link_type_t link_type;
2550     bd_addr_t addr;
2551 #endif
2552 
2553     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2554 
2555     switch (hci_event_packet_get_type(packet)) {
2556 
2557         case HCI_EVENT_COMMAND_COMPLETE:
2558             handle_command_complete_event(packet, size);
2559             break;
2560 
2561         case HCI_EVENT_COMMAND_STATUS:
2562             // get num cmd packets - limit to 1 to reduce complexity
2563             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2564 
2565             // check command status to detected failed outgoing connections
2566             create_connection_cmd = 0;
2567 #ifdef ENABLE_CLASSIC
2568             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2569                 create_connection_cmd = 1;
2570             }
2571 #endif
2572 #ifdef ENABLE_LE_CENTRAL
2573             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2574                 create_connection_cmd = 1;
2575             }
2576 #endif
2577             if (create_connection_cmd) {
2578                 uint8_t status = hci_event_command_status_get_status(packet);
2579                 addr_type = hci_stack->outgoing_addr_type;
2580                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2581                 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);
2582 
2583                 // reset outgoing address info
2584                 memset(hci_stack->outgoing_addr, 0, 6);
2585                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2586 
2587                 // on error
2588                 if (status != ERROR_CODE_SUCCESS){
2589 #ifdef ENABLE_LE_CENTRAL
2590                     if (hci_is_le_connection_type(addr_type)){
2591                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2592                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2593                     }
2594 #endif
2595                     // error => outgoing connection failed
2596                     if (conn != NULL){
2597                         hci_handle_connection_failed(conn, status);
2598                     }
2599                 }
2600             }
2601 
2602 #ifdef ENABLE_CLASSIC
2603             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2604                 uint8_t status = hci_event_command_status_get_status(packet);
2605                 log_info("command status (inquiry), status %x", status);
2606                 if (status == ERROR_CODE_SUCCESS) {
2607                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2608                 } else {
2609                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2610                 }
2611             }
2612 #endif
2613             break;
2614 
2615         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2616             if (size < 3) return;
2617             uint16_t num_handles = packet[2];
2618             if (size != (3u + num_handles * 4u)) return;
2619             uint16_t offset = 3;
2620             for (i=0; i<num_handles;i++){
2621                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2622                 offset += 2u;
2623                 uint16_t num_packets = little_endian_read_16(packet, offset);
2624                 offset += 2u;
2625 
2626                 conn = hci_connection_for_handle(handle);
2627                 if (!conn){
2628                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2629                     continue;
2630                 }
2631 
2632                 if (conn->num_packets_sent >= num_packets){
2633                     conn->num_packets_sent -= num_packets;
2634                 } else {
2635                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2636                     conn->num_packets_sent = 0;
2637                 }
2638                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2639 
2640 #ifdef ENABLE_CLASSIC
2641                 // For SCO, we do the can_send_now_check here
2642                 hci_notify_if_sco_can_send_now();
2643 #endif
2644             }
2645             break;
2646         }
2647 
2648 #ifdef ENABLE_CLASSIC
2649         case HCI_EVENT_INQUIRY_COMPLETE:
2650             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2651                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2652                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2653                 hci_emit_event(event, sizeof(event), 1);
2654             }
2655             break;
2656         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2657             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2658                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2659             }
2660             break;
2661         case HCI_EVENT_CONNECTION_REQUEST:
2662             reverse_bd_addr(&packet[2], addr);
2663             link_type = (hci_link_type_t) packet[11];
2664 
2665             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2666             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2667                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2668                 bd_addr_copy(hci_stack->decline_addr, addr);
2669                 break;
2670             }
2671 
2672             if (hci_stack->gap_classic_accept_callback != NULL){
2673                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2674                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2675                     bd_addr_copy(hci_stack->decline_addr, addr);
2676                     break;
2677                 }
2678             }
2679 
2680             // TODO: eval COD 8-10
2681             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2682             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2683             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2684             if (!conn) {
2685                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2686             }
2687             if (!conn) {
2688                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2689                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2690                 bd_addr_copy(hci_stack->decline_addr, addr);
2691                 break;
2692             }
2693             conn->role  = HCI_ROLE_SLAVE;
2694             conn->state = RECEIVED_CONNECTION_REQUEST;
2695             // store info about eSCO
2696             if (link_type == HCI_LINK_TYPE_ESCO){
2697                 conn->remote_supported_features[0] |= 1;
2698             }
2699             hci_run();
2700             break;
2701 
2702         case HCI_EVENT_CONNECTION_COMPLETE:
2703             // Connection management
2704             reverse_bd_addr(&packet[5], addr);
2705             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2706             addr_type = BD_ADDR_TYPE_ACL;
2707             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2708             if (conn) {
2709                 if (!packet[2]){
2710                     conn->state = OPEN;
2711                     conn->con_handle = little_endian_read_16(packet, 3);
2712 
2713                     // queue get remote feature
2714                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2715 
2716                     // queue set supervision timeout if we're master
2717                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2718                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2719                     }
2720 
2721                     // restart timer
2722                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2723                     btstack_run_loop_add_timer(&conn->timeout);
2724 
2725                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2726 
2727                     hci_emit_nr_connections_changed();
2728                 } else {
2729                     // connection failed
2730                     hci_handle_connection_failed(conn, packet[2]);
2731                 }
2732             }
2733             break;
2734 
2735         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2736             reverse_bd_addr(&packet[5], addr);
2737             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2738             if (packet[2]){
2739                 // connection failed
2740                 break;
2741             }
2742             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2743             if (!conn) {
2744                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2745             }
2746             if (!conn) {
2747                 break;
2748             }
2749             conn->state = OPEN;
2750             conn->con_handle = little_endian_read_16(packet, 3);
2751 
2752 #ifdef ENABLE_SCO_OVER_HCI
2753             // update SCO
2754             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2755                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2756             }
2757             // trigger can send now
2758             if (hci_have_usb_transport()){
2759                 hci_stack->sco_can_send_now = true;
2760             }
2761 #endif
2762 #ifdef HAVE_SCO_TRANSPORT
2763             // configure sco transport
2764             if (hci_stack->sco_transport != NULL){
2765                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2766                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2767             }
2768 #endif
2769             break;
2770 
2771         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2772             handle = little_endian_read_16(packet, 3);
2773             conn = hci_connection_for_handle(handle);
2774             if (!conn) break;
2775             if (!packet[2]){
2776                 const uint8_t * features = &packet[5];
2777                 hci_handle_remote_features_page_0(conn, features);
2778 
2779                 // read extended features if possible
2780                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2781                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2782                     break;
2783                 }
2784             }
2785             hci_handle_remote_features_received(conn);
2786             break;
2787 
2788         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2789             handle = little_endian_read_16(packet, 3);
2790             conn = hci_connection_for_handle(handle);
2791             if (!conn) break;
2792             // status = ok, page = 1
2793             if (!packet[2]) {
2794                 uint8_t page_number = packet[5];
2795                 uint8_t maximum_page_number = packet[6];
2796                 const uint8_t * features = &packet[7];
2797                 bool done = false;
2798                 switch (page_number){
2799                     case 1:
2800                         hci_handle_remote_features_page_1(conn, features);
2801                         if (maximum_page_number >= 2){
2802                             // get Secure Connections (Controller) from Page 2 if available
2803                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2804                         } else {
2805                             // otherwise, assume SC (Controller) == SC (Host)
2806                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2807                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2808                             }
2809                             done = true;
2810                         }
2811                         break;
2812                     case 2:
2813                         hci_handle_remote_features_page_2(conn, features);
2814                         done = true;
2815                         break;
2816                     default:
2817                         break;
2818                 }
2819                 if (!done) break;
2820             }
2821             hci_handle_remote_features_received(conn);
2822             break;
2823 
2824         case HCI_EVENT_LINK_KEY_REQUEST:
2825 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2826             hci_event_link_key_request_get_bd_addr(packet, addr);
2827             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2828             if (!conn) break;
2829 
2830             // lookup link key in db if not cached
2831             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2832                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2833             }
2834 
2835             // response sent by hci_run()
2836             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2837 #endif
2838             break;
2839 
2840         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2841             hci_event_link_key_request_get_bd_addr(packet, addr);
2842             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2843             if (!conn) break;
2844 
2845             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2846 
2847             // CVE-2020-26555: ignore NULL link key
2848             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2849             if (btstack_is_null(&packet[8], 16)) break;
2850 
2851             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2852             // Change Connection Encryption keeps link key type
2853             if (link_key_type != CHANGED_COMBINATION_KEY){
2854                 conn->link_key_type = link_key_type;
2855             }
2856 
2857             // cache link key. link keys stored in little-endian format for legacy reasons
2858             memcpy(&conn->link_key, &packet[8], 16);
2859 
2860             // only store link key:
2861             // - if bondable enabled
2862             if (hci_stack->bondable == false) break;
2863             // - if security level sufficient
2864             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2865             // - for SSP, also check if remote side requested bonding as well
2866             if (conn->link_key_type != COMBINATION_KEY){
2867                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2868                 if (!remote_bonding){
2869                     break;
2870                 }
2871             }
2872             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2873             break;
2874         }
2875 
2876         case HCI_EVENT_PIN_CODE_REQUEST:
2877             hci_event_pin_code_request_get_bd_addr(packet, addr);
2878             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2879             if (!conn) break;
2880 
2881             hci_pairing_started(conn, false);
2882             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2883             if (!hci_stack->bondable ){
2884                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2885                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2886                 hci_run();
2887                 return;
2888             }
2889             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2890             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2891                 log_info("Level 4 required, but SC not supported -> abort");
2892                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2893                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2894                 hci_run();
2895                 return;
2896             }
2897             break;
2898 
2899         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2900             hci_event_io_capability_response_get_bd_addr(packet, addr);
2901             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2902             if (!conn) break;
2903 
2904             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2905             hci_pairing_started(conn, true);
2906             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2907             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2908 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2909             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2910 #endif
2911             break;
2912 
2913         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2914             hci_event_io_capability_response_get_bd_addr(packet, addr);
2915             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2916             if (!conn) break;
2917 
2918             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2919             hci_connection_timestamp(conn);
2920             hci_pairing_started(conn, true);
2921             break;
2922 
2923 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2924         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2925             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2926             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2927             if (!conn) break;
2928 
2929             hci_connection_timestamp(conn);
2930 
2931             hci_pairing_started(conn, true);
2932 
2933             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2934             break;
2935 #endif
2936 
2937         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2938             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2939             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2940             if (!conn) break;
2941             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2942                 if (hci_stack->ssp_auto_accept){
2943                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2944                 };
2945             } else {
2946                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2947                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2948                 // don't forward event to app
2949                 hci_run();
2950                 return;
2951             }
2952             break;
2953 
2954         case HCI_EVENT_USER_PASSKEY_REQUEST:
2955             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2956             if (hci_stack->ssp_auto_accept){
2957                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2958             };
2959             break;
2960 
2961         case HCI_EVENT_MODE_CHANGE:
2962             handle = hci_event_mode_change_get_handle(packet);
2963             conn = hci_connection_for_handle(handle);
2964             if (!conn) break;
2965             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2966             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2967             break;
2968 #endif
2969 
2970         case HCI_EVENT_ENCRYPTION_CHANGE:
2971             handle = hci_event_encryption_change_get_connection_handle(packet);
2972             conn = hci_connection_for_handle(handle);
2973             if (!conn) break;
2974             if (hci_event_encryption_change_get_status(packet) == 0u) {
2975                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2976                 if (encryption_enabled){
2977                     if (hci_is_le_connection(conn)){
2978                         // For LE, we accept connection as encrypted
2979                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2980                     }
2981 #ifdef ENABLE_CLASSIC
2982                     else {
2983 
2984                         // dedicated bonding: send result and disconnect
2985                         if (conn->bonding_flags & BONDING_DEDICATED){
2986                             conn->bonding_flags &= ~BONDING_DEDICATED;
2987                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2988                             conn->bonding_status = packet[2];
2989                             break;
2990                         }
2991 
2992                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2993                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2994                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2995                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2996                             log_info("SC during pairing, but only E0 now -> abort");
2997                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2998                             break;
2999                         }
3000 
3001                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3002                         if (connected_uses_aes_ccm){
3003                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3004                         }
3005 
3006 #ifdef ENABLE_TESTING_SUPPORT
3007                         // work around for issue with PTS dongle
3008                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3009 #endif
3010 
3011                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3012                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3013                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3014                         } else {
3015                             // if not, pretend everything is perfect
3016                             hci_handle_read_encryption_key_size_complete(conn, 16);
3017                         }
3018                     }
3019 #endif
3020                 } else {
3021                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3022                 }
3023             }
3024 
3025             break;
3026 
3027 #ifdef ENABLE_CLASSIC
3028         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3029             handle = hci_event_authentication_complete_get_connection_handle(packet);
3030             conn = hci_connection_for_handle(handle);
3031             if (!conn) break;
3032 
3033             // clear authentication active flag
3034             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3035             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3036 
3037             // authenticated only if auth status == 0
3038             if (hci_event_authentication_complete_get_status(packet) == 0){
3039                 // authenticated
3040                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3041 
3042                 // If not already encrypted, start encryption
3043                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3044                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3045                     break;
3046                 }
3047             }
3048 
3049             // emit updated security level
3050             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3051             break;
3052 
3053         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3054             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3055             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3056             if (!conn) break;
3057 
3058             // treat successfully paired connection as authenticated
3059             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3060                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3061             }
3062 
3063             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3064             break;
3065 #endif
3066 
3067         // HCI_EVENT_DISCONNECTION_COMPLETE
3068         // has been split, to first notify stack before shutting connection down
3069         // see end of function, too.
3070         case HCI_EVENT_DISCONNECTION_COMPLETE:
3071             if (packet[2]) break;   // status != 0
3072             handle = little_endian_read_16(packet, 3);
3073             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3074             if (hci_stack->acl_fragmentation_total_size > 0u) {
3075                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3076                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3077                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3078                     hci_stack->acl_fragmentation_total_size = 0;
3079                     hci_stack->acl_fragmentation_pos = 0;
3080                     if (release_buffer){
3081                         hci_release_packet_buffer();
3082                     }
3083                 }
3084             }
3085 
3086             conn = hci_connection_for_handle(handle);
3087             if (!conn) break;
3088 #ifdef ENABLE_CLASSIC
3089             // pairing failed if it was ongoing
3090             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3091 #endif
3092 
3093             // emit dedicatd bonding event
3094             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3095                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3096             }
3097 
3098             // mark connection for shutdown, stop timers, reset state
3099             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3100             hci_connection_stop_timer(conn);
3101             hci_connection_init(conn);
3102 
3103 #ifdef ENABLE_BLE
3104 #ifdef ENABLE_LE_PERIPHERAL
3105             // re-enable advertisements for le connections if active
3106             if (hci_is_le_connection(conn)){
3107                 hci_update_advertisements_enabled_for_current_roles();
3108             }
3109 #endif
3110 #endif
3111             break;
3112 
3113         case HCI_EVENT_HARDWARE_ERROR:
3114             log_error("Hardware Error: 0x%02x", packet[2]);
3115             if (hci_stack->hardware_error_callback){
3116                 (*hci_stack->hardware_error_callback)(packet[2]);
3117             } else {
3118                 // if no special requests, just reboot stack
3119                 hci_power_control_off();
3120                 hci_power_control_on();
3121             }
3122             break;
3123 
3124 #ifdef ENABLE_CLASSIC
3125         case HCI_EVENT_ROLE_CHANGE:
3126             if (packet[2]) break;   // status != 0
3127             reverse_bd_addr(&packet[3], addr);
3128             addr_type = BD_ADDR_TYPE_ACL;
3129             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3130             if (!conn) break;
3131             conn->role = packet[9];
3132             break;
3133 #endif
3134 
3135         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3136             // release packet buffer only for asynchronous transport and if there are not further fragements
3137             if (hci_transport_synchronous()) {
3138                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3139                 return; // instead of break: to avoid re-entering hci_run()
3140             }
3141             hci_stack->acl_fragmentation_tx_active = 0;
3142             if (hci_stack->acl_fragmentation_total_size) break;
3143             hci_release_packet_buffer();
3144 
3145             // L2CAP receives this event via the hci_emit_event below
3146 
3147 #ifdef ENABLE_CLASSIC
3148             // For SCO, we do the can_send_now_check here
3149             hci_notify_if_sco_can_send_now();
3150 #endif
3151             break;
3152 
3153 #ifdef ENABLE_CLASSIC
3154         case HCI_EVENT_SCO_CAN_SEND_NOW:
3155             // For SCO, we do the can_send_now_check here
3156             hci_stack->sco_can_send_now = true;
3157             hci_notify_if_sco_can_send_now();
3158             return;
3159 
3160         // explode inquriy results for easier consumption
3161         case HCI_EVENT_INQUIRY_RESULT:
3162         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3163         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3164             gap_inquiry_explode(packet, size);
3165             break;
3166 #endif
3167 
3168 #ifdef ENABLE_BLE
3169         case HCI_EVENT_LE_META:
3170             switch (packet[2]){
3171 #ifdef ENABLE_LE_CENTRAL
3172                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3173                     // log_info("advertising report received");
3174                     if (!hci_stack->le_scanning_enabled) break;
3175                     le_handle_advertisement_report(packet, size);
3176                     break;
3177 #endif
3178                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3179 					event_handle_le_connection_complete(packet);
3180                     break;
3181 
3182                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3183                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3184                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3185                     conn = hci_connection_for_handle(handle);
3186                     if (!conn) break;
3187                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3188                     break;
3189 
3190                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3191                     // connection
3192                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3193                     conn = hci_connection_for_handle(handle);
3194                     if (conn) {
3195                         // read arguments
3196                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3197                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3198                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3199                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3200 
3201                         // validate against current connection parameter range
3202                         le_connection_parameter_range_t existing_range;
3203                         gap_get_connection_parameter_range(&existing_range);
3204                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3205                         if (update_parameter){
3206                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3207                             conn->le_conn_interval_min = le_conn_interval_min;
3208                             conn->le_conn_interval_max = le_conn_interval_max;
3209                             conn->le_conn_latency = le_conn_latency;
3210                             conn->le_supervision_timeout = le_supervision_timeout;
3211                         } else {
3212                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3213                         }
3214                     }
3215                     break;
3216 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3217                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3218                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3219                     conn = hci_connection_for_handle(handle);
3220                     if (conn) {
3221                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3222                     }
3223                     break;
3224 #endif
3225                 default:
3226                     break;
3227             }
3228             break;
3229 #endif
3230         case HCI_EVENT_VENDOR_SPECIFIC:
3231             // Vendor specific commands often create vendor specific event instead of num completed packets
3232             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3233             switch (hci_stack->manufacturer){
3234                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3235                     hci_stack->num_cmd_packets = 1;
3236                     break;
3237                 default:
3238                     break;
3239             }
3240             break;
3241         default:
3242             break;
3243     }
3244 
3245     handle_event_for_current_stack_state(packet, size);
3246 
3247     // notify upper stack
3248 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3249 
3250     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3251     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3252 		handle = little_endian_read_16(packet, 3);
3253 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3254 		// discard connection if app did not trigger a reconnect in the event handler
3255 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3256 			hci_shutdown_connection(aConn);
3257 		}
3258     }
3259 
3260 	// execute main loop
3261 	hci_run();
3262 }
3263 
3264 #ifdef ENABLE_CLASSIC
3265 
3266 #ifdef ENABLE_SCO_OVER_HCI
3267 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3268 static void sco_schedule_tx(hci_connection_t * conn);
3269 
3270 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3271     log_debug("SCO TX Timeout");
3272     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3273     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3274     if (!conn) return;
3275 
3276     // trigger send
3277     conn->sco_tx_ready = 1;
3278     // extra packet if CVSD but SCO buffer is too short
3279     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3280         conn->sco_tx_ready++;
3281     }
3282     hci_notify_if_sco_can_send_now();
3283 }
3284 
3285 
3286 #define SCO_TX_AFTER_RX_MS (6)
3287 
3288 static void sco_schedule_tx(hci_connection_t * conn){
3289 
3290     uint32_t now = btstack_run_loop_get_time_ms();
3291     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3292     int time_delta_ms = sco_tx_ms - now;
3293 
3294     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3295 
3296     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3297     btstack_run_loop_remove_timer(timer);
3298     btstack_run_loop_set_timer(timer, time_delta_ms);
3299     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3300     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3301     btstack_run_loop_add_timer(timer);
3302 }
3303 #endif
3304 
3305 static void sco_handler(uint8_t * packet, uint16_t size){
3306     // lookup connection struct
3307     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3308     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3309     if (!conn) return;
3310 
3311 #ifdef ENABLE_SCO_OVER_HCI
3312     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3313     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3314         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3315             packet[2] = 0x3c;
3316             memmove(&packet[3], &packet[23], 63);
3317             size = 63;
3318         }
3319     }
3320 
3321     if (hci_have_usb_transport()){
3322         // Nothing to do
3323     } else {
3324         // 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);
3325         if (hci_stack->synchronous_flow_control_enabled == 0){
3326             uint32_t now = btstack_run_loop_get_time_ms();
3327 
3328             if (!conn->sco_rx_valid){
3329                 // ignore first 10 packets
3330                 conn->sco_rx_count++;
3331                 // log_debug("sco rx count %u", conn->sco_rx_count);
3332                 if (conn->sco_rx_count == 10) {
3333                     // use first timestamp as is and pretent it just started
3334                     conn->sco_rx_ms = now;
3335                     conn->sco_rx_valid = 1;
3336                     conn->sco_rx_count = 0;
3337                     sco_schedule_tx(conn);
3338                 }
3339             } else {
3340                 // track expected arrival timme
3341                 conn->sco_rx_count++;
3342                 conn->sco_rx_ms += 7;
3343                 int delta = (int32_t) (now - conn->sco_rx_ms);
3344                 if (delta > 0){
3345                     conn->sco_rx_ms++;
3346                 }
3347                 // log_debug("sco rx %u", conn->sco_rx_ms);
3348                 sco_schedule_tx(conn);
3349             }
3350         }
3351     }
3352 #endif
3353 
3354     // deliver to app
3355     if (hci_stack->sco_packet_handler) {
3356         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3357     }
3358 
3359 #ifdef HAVE_SCO_TRANSPORT
3360     // We can send one packet for each received packet
3361     conn->sco_tx_ready++;
3362     hci_notify_if_sco_can_send_now();
3363 #endif
3364 
3365 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3366     conn->num_packets_completed++;
3367     hci_stack->host_completed_packets = 1;
3368     hci_run();
3369 #endif
3370 }
3371 #endif
3372 
3373 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3374     hci_dump_packet(packet_type, 1, packet, size);
3375     switch (packet_type) {
3376         case HCI_EVENT_PACKET:
3377             event_handler(packet, size);
3378             break;
3379         case HCI_ACL_DATA_PACKET:
3380             acl_handler(packet, size);
3381             break;
3382 #ifdef ENABLE_CLASSIC
3383         case HCI_SCO_DATA_PACKET:
3384             sco_handler(packet, size);
3385             break;
3386 #endif
3387         default:
3388             break;
3389     }
3390 }
3391 
3392 /**
3393  * @brief Add event packet handler.
3394  */
3395 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3396     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3397 }
3398 
3399 
3400 /** Register HCI packet handlers */
3401 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3402     hci_stack->acl_packet_handler = handler;
3403 }
3404 
3405 #ifdef ENABLE_CLASSIC
3406 /**
3407  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3408  */
3409 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3410     hci_stack->sco_packet_handler = handler;
3411 }
3412 #endif
3413 
3414 static void hci_state_reset(void){
3415     // no connections yet
3416     hci_stack->connections = NULL;
3417 
3418     // keep discoverable/connectable as this has been requested by the client(s)
3419     // hci_stack->discoverable = 0;
3420     // hci_stack->connectable = 0;
3421     // hci_stack->bondable = 1;
3422     // hci_stack->own_addr_type = 0;
3423 
3424     // buffer is free
3425     hci_stack->hci_packet_buffer_reserved = false;
3426 
3427     // no pending cmds
3428     hci_stack->decline_reason = 0;
3429 
3430     hci_stack->secure_connections_active = false;
3431 
3432 #ifdef ENABLE_CLASSIC
3433     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3434     hci_stack->gap_tasks =
3435             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3436             GAP_TASK_SET_CLASS_OF_DEVICE |
3437             GAP_TASK_SET_LOCAL_NAME |
3438             GAP_TASK_SET_EIR_DATA |
3439             GAP_TASK_WRITE_SCAN_ENABLE;
3440 #endif
3441 
3442 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3443     hci_stack->classic_read_local_oob_data = true;
3444     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3445 #endif
3446 
3447     // LE
3448 #ifdef ENABLE_BLE
3449     memset(hci_stack->le_random_address, 0, 6);
3450     hci_stack->le_random_address_set = 0;
3451 #endif
3452 #ifdef ENABLE_LE_CENTRAL
3453     hci_stack->le_scanning_active  = false;
3454     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3455     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3456     hci_stack->le_whitelist_capacity = 0;
3457 #endif
3458 #ifdef ENABLE_LE_PERIPHERAL
3459     hci_stack->le_advertisements_active = false;
3460     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3461         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3462     }
3463     if (hci_stack->le_advertisements_data != NULL){
3464         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3465     }
3466 #endif
3467 }
3468 
3469 #ifdef ENABLE_CLASSIC
3470 /**
3471  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3472  */
3473 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3474     // store and open remote device db
3475     hci_stack->link_key_db = link_key_db;
3476     if (hci_stack->link_key_db) {
3477         hci_stack->link_key_db->open();
3478     }
3479 }
3480 #endif
3481 
3482 void hci_init(const hci_transport_t *transport, const void *config){
3483 
3484 #ifdef HAVE_MALLOC
3485     if (!hci_stack) {
3486         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3487     }
3488 #else
3489     hci_stack = &hci_stack_static;
3490 #endif
3491     memset(hci_stack, 0, sizeof(hci_stack_t));
3492 
3493     // reference to use transport layer implementation
3494     hci_stack->hci_transport = transport;
3495 
3496     // reference to used config
3497     hci_stack->config = config;
3498 
3499     // setup pointer for outgoing packet buffer
3500     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3501 
3502     // max acl payload size defined in config.h
3503     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3504 
3505     // register packet handlers with transport
3506     transport->register_packet_handler(&packet_handler);
3507 
3508     hci_stack->state = HCI_STATE_OFF;
3509 
3510     // class of device
3511     hci_stack->class_of_device = 0x007a020c; // Smartphone
3512 
3513     // bondable by default
3514     hci_stack->bondable = 1;
3515 
3516 #ifdef ENABLE_CLASSIC
3517     // classic name
3518     hci_stack->local_name = default_classic_name;
3519 
3520     // Master slave policy
3521     hci_stack->master_slave_policy = 1;
3522 
3523     // Allow Role Switch
3524     hci_stack->allow_role_switch = 1;
3525 
3526     // Default / minimum security level = 2
3527     hci_stack->gap_security_level = LEVEL_2;
3528 
3529     // Default Security Mode 4
3530     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3531 
3532     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3533     hci_stack->gap_required_encyrption_key_size = 7;
3534 
3535     // Link Supervision Timeout
3536     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3537 
3538 #endif
3539 
3540     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3541     hci_stack->ssp_enable = 1;
3542     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3543     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3544     hci_stack->ssp_auto_accept = 1;
3545 
3546     // Secure Connections: enable (requires support from Controller)
3547     hci_stack->secure_connections_enable = true;
3548 
3549     // voice setting - signed 16 bit pcm data with CVSD over the air
3550     hci_stack->sco_voice_setting = 0x60;
3551 
3552 #ifdef ENABLE_LE_CENTRAL
3553     // connection parameter to use for outgoing connections
3554     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3555     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3556     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3557     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3558     hci_stack->le_connection_latency      = 4;         // 4
3559     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3560     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3561     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3562 
3563     // default LE Scanning
3564     hci_stack->le_scan_type     =   0x1; // active
3565     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3566     hci_stack->le_scan_window   =  0x30; //  30 ms
3567 #endif
3568 
3569 #ifdef ENABLE_LE_PERIPHERAL
3570     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3571 #endif
3572 
3573     // connection parameter range used to answer connection parameter update requests in l2cap
3574     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3575     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3576     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3577     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3578     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3579     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3580 
3581     hci_state_reset();
3582 }
3583 
3584 void hci_deinit(void){
3585 #ifdef HAVE_MALLOC
3586     if (hci_stack) {
3587         free(hci_stack);
3588     }
3589 #endif
3590     hci_stack = NULL;
3591 
3592 #ifdef ENABLE_CLASSIC
3593     disable_l2cap_timeouts = 0;
3594 #endif
3595 }
3596 
3597 /**
3598  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3599  */
3600 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3601     hci_stack->chipset = chipset_driver;
3602 
3603     // reset chipset driver - init is also called on power_up
3604     if (hci_stack->chipset && hci_stack->chipset->init){
3605         hci_stack->chipset->init(hci_stack->config);
3606     }
3607 }
3608 
3609 /**
3610  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3611  */
3612 void hci_set_control(const btstack_control_t *hardware_control){
3613     // references to used control implementation
3614     hci_stack->control = hardware_control;
3615     // init with transport config
3616     hardware_control->init(hci_stack->config);
3617 }
3618 
3619 void hci_close(void){
3620 
3621 #ifdef ENABLE_CLASSIC
3622     // close remote device db
3623     if (hci_stack->link_key_db) {
3624         hci_stack->link_key_db->close();
3625     }
3626 #endif
3627 
3628     btstack_linked_list_iterator_t lit;
3629     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3630     while (btstack_linked_list_iterator_has_next(&lit)){
3631         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3632         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3633         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3634         hci_shutdown_connection(connection);
3635     }
3636 
3637     hci_power_control(HCI_POWER_OFF);
3638 
3639 #ifdef HAVE_MALLOC
3640     free(hci_stack);
3641 #endif
3642     hci_stack = NULL;
3643 }
3644 
3645 #ifdef HAVE_SCO_TRANSPORT
3646 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3647     hci_stack->sco_transport = sco_transport;
3648     sco_transport->register_packet_handler(&packet_handler);
3649 }
3650 #endif
3651 
3652 #ifdef ENABLE_CLASSIC
3653 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3654     // validate ranage and set
3655     if (encryption_key_size < 7)  return;
3656     if (encryption_key_size > 16) return;
3657     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3658 }
3659 
3660 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3661     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3662         hci_stack->gap_security_mode = security_mode;
3663         return ERROR_CODE_SUCCESS;
3664     } else {
3665         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3666     }
3667 }
3668 
3669 gap_security_mode_t gap_get_security_mode(void){
3670     return hci_stack->gap_security_mode;
3671 }
3672 
3673 void gap_set_security_level(gap_security_level_t security_level){
3674     hci_stack->gap_security_level = security_level;
3675 }
3676 
3677 gap_security_level_t gap_get_security_level(void){
3678     if (hci_stack->gap_secure_connections_only_mode){
3679         return LEVEL_4;
3680     }
3681     return hci_stack->gap_security_level;
3682 }
3683 
3684 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3685     hci_stack->gap_minimal_service_security_level = security_level;
3686 }
3687 
3688 void gap_set_secure_connections_only_mode(bool enable){
3689     hci_stack->gap_secure_connections_only_mode = enable;
3690 }
3691 
3692 bool gap_get_secure_connections_only_mode(void){
3693     return hci_stack->gap_secure_connections_only_mode;
3694 }
3695 #endif
3696 
3697 #ifdef ENABLE_CLASSIC
3698 void gap_set_class_of_device(uint32_t class_of_device){
3699     hci_stack->class_of_device = class_of_device;
3700     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3701     hci_run();
3702 }
3703 
3704 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3705     hci_stack->default_link_policy_settings = default_link_policy_settings;
3706     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3707     hci_run();
3708 }
3709 
3710 void gap_set_allow_role_switch(bool allow_role_switch){
3711     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3712 }
3713 
3714 uint8_t hci_get_allow_role_switch(void){
3715     return  hci_stack->allow_role_switch;
3716 }
3717 
3718 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3719     hci_stack->link_supervision_timeout = link_supervision_timeout;
3720 }
3721 
3722 void hci_disable_l2cap_timeout_check(void){
3723     disable_l2cap_timeouts = 1;
3724 }
3725 #endif
3726 
3727 #ifndef HAVE_HOST_CONTROLLER_API
3728 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3729 void hci_set_bd_addr(bd_addr_t addr){
3730     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3731     hci_stack->custom_bd_addr_set = 1;
3732 }
3733 #endif
3734 
3735 // State-Module-Driver overview
3736 // state                    module  low-level
3737 // HCI_STATE_OFF             off      close
3738 // HCI_STATE_INITIALIZING,   on       open
3739 // HCI_STATE_WORKING,        on       open
3740 // HCI_STATE_HALTING,        on       open
3741 // HCI_STATE_SLEEPING,    off/sleep   close
3742 // HCI_STATE_FALLING_ASLEEP  on       open
3743 
3744 static int hci_power_control_on(void){
3745 
3746     // power on
3747     int err = 0;
3748     if (hci_stack->control && hci_stack->control->on){
3749         err = (*hci_stack->control->on)();
3750     }
3751     if (err){
3752         log_error( "POWER_ON failed");
3753         hci_emit_hci_open_failed();
3754         return err;
3755     }
3756 
3757     // int chipset driver
3758     if (hci_stack->chipset && hci_stack->chipset->init){
3759         hci_stack->chipset->init(hci_stack->config);
3760     }
3761 
3762     // init transport
3763     if (hci_stack->hci_transport->init){
3764         hci_stack->hci_transport->init(hci_stack->config);
3765     }
3766 
3767     // open transport
3768     err = hci_stack->hci_transport->open();
3769     if (err){
3770         log_error( "HCI_INIT failed, turning Bluetooth off again");
3771         if (hci_stack->control && hci_stack->control->off){
3772             (*hci_stack->control->off)();
3773         }
3774         hci_emit_hci_open_failed();
3775         return err;
3776     }
3777     return 0;
3778 }
3779 
3780 static void hci_power_control_off(void){
3781 
3782     log_info("hci_power_control_off");
3783 
3784     // close low-level device
3785     hci_stack->hci_transport->close();
3786 
3787     log_info("hci_power_control_off - hci_transport closed");
3788 
3789     // power off
3790     if (hci_stack->control && hci_stack->control->off){
3791         (*hci_stack->control->off)();
3792     }
3793 
3794     log_info("hci_power_control_off - control closed");
3795 
3796     hci_stack->state = HCI_STATE_OFF;
3797 }
3798 
3799 static void hci_power_control_sleep(void){
3800 
3801     log_info("hci_power_control_sleep");
3802 
3803 #if 0
3804     // don't close serial port during sleep
3805 
3806     // close low-level device
3807     hci_stack->hci_transport->close(hci_stack->config);
3808 #endif
3809 
3810     // sleep mode
3811     if (hci_stack->control && hci_stack->control->sleep){
3812         (*hci_stack->control->sleep)();
3813     }
3814 
3815     hci_stack->state = HCI_STATE_SLEEPING;
3816 }
3817 
3818 static int hci_power_control_wake(void){
3819 
3820     log_info("hci_power_control_wake");
3821 
3822     // wake on
3823     if (hci_stack->control && hci_stack->control->wake){
3824         (*hci_stack->control->wake)();
3825     }
3826 
3827 #if 0
3828     // open low-level device
3829     int err = hci_stack->hci_transport->open(hci_stack->config);
3830     if (err){
3831         log_error( "HCI_INIT failed, turning Bluetooth off again");
3832         if (hci_stack->control && hci_stack->control->off){
3833             (*hci_stack->control->off)();
3834         }
3835         hci_emit_hci_open_failed();
3836         return err;
3837     }
3838 #endif
3839 
3840     return 0;
3841 }
3842 
3843 static void hci_power_transition_to_initializing(void){
3844     // set up state machine
3845     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3846     hci_stack->hci_packet_buffer_reserved = false;
3847     hci_stack->state = HCI_STATE_INITIALIZING;
3848     hci_stack->substate = HCI_INIT_SEND_RESET;
3849 }
3850 
3851 // returns error
3852 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3853     int err;
3854     switch (power_mode){
3855         case HCI_POWER_ON:
3856             err = hci_power_control_on();
3857             if (err != 0) {
3858                 log_error("hci_power_control_on() error %d", err);
3859                 return err;
3860             }
3861             hci_power_transition_to_initializing();
3862             break;
3863         case HCI_POWER_OFF:
3864             // do nothing
3865             break;
3866         case HCI_POWER_SLEEP:
3867             // do nothing (with SLEEP == OFF)
3868             break;
3869         default:
3870             btstack_assert(false);
3871             break;
3872     }
3873     return ERROR_CODE_SUCCESS;
3874 }
3875 
3876 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3877     switch (power_mode){
3878         case HCI_POWER_ON:
3879             // do nothing
3880             break;
3881         case HCI_POWER_OFF:
3882             // no connections yet, just turn it off
3883             hci_power_control_off();
3884             break;
3885         case HCI_POWER_SLEEP:
3886             // no connections yet, just turn it off
3887             hci_power_control_sleep();
3888             break;
3889         default:
3890             btstack_assert(false);
3891             break;
3892     }
3893     return ERROR_CODE_SUCCESS;
3894 }
3895 
3896 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3897     switch (power_mode){
3898         case HCI_POWER_ON:
3899             // do nothing
3900             break;
3901         case HCI_POWER_OFF:
3902             // see hci_run
3903             hci_stack->state = HCI_STATE_HALTING;
3904             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3905             break;
3906         case HCI_POWER_SLEEP:
3907             // see hci_run
3908             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3909             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3910             break;
3911         default:
3912             btstack_assert(false);
3913             break;
3914     }
3915     return ERROR_CODE_SUCCESS;
3916 }
3917 
3918 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3919     switch (power_mode){
3920         case HCI_POWER_ON:
3921             hci_power_transition_to_initializing();
3922             break;
3923         case HCI_POWER_OFF:
3924             // do nothing
3925             break;
3926         case HCI_POWER_SLEEP:
3927             // see hci_run
3928             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3929             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3930             break;
3931         default:
3932             btstack_assert(false);
3933             break;
3934     }
3935     return ERROR_CODE_SUCCESS;
3936 }
3937 
3938 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3939     switch (power_mode){
3940         case HCI_POWER_ON:
3941             hci_power_transition_to_initializing();
3942             break;
3943         case HCI_POWER_OFF:
3944             // see hci_run
3945             hci_stack->state = HCI_STATE_HALTING;
3946             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3947             break;
3948         case HCI_POWER_SLEEP:
3949             // do nothing
3950             break;
3951         default:
3952             btstack_assert(false);
3953             break;
3954     }
3955     return ERROR_CODE_SUCCESS;
3956 }
3957 
3958 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3959     int err;
3960     switch (power_mode){
3961         case HCI_POWER_ON:
3962             err = hci_power_control_wake();
3963             if (err) return err;
3964             hci_power_transition_to_initializing();
3965             break;
3966         case HCI_POWER_OFF:
3967             hci_stack->state = HCI_STATE_HALTING;
3968             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3969             break;
3970         case HCI_POWER_SLEEP:
3971             // do nothing
3972             break;
3973         default:
3974             btstack_assert(false);
3975             break;
3976     }
3977     return ERROR_CODE_SUCCESS;
3978 }
3979 
3980 int hci_power_control(HCI_POWER_MODE power_mode){
3981     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3982     int err = 0;
3983     switch (hci_stack->state){
3984         case HCI_STATE_OFF:
3985             err = hci_power_control_state_off(power_mode);
3986             break;
3987         case HCI_STATE_INITIALIZING:
3988             err = hci_power_control_state_initializing(power_mode);
3989             break;
3990         case HCI_STATE_WORKING:
3991             err = hci_power_control_state_working(power_mode);
3992             break;
3993         case HCI_STATE_HALTING:
3994             err = hci_power_control_state_halting(power_mode);
3995             break;
3996         case HCI_STATE_FALLING_ASLEEP:
3997             err = hci_power_control_state_falling_asleep(power_mode);
3998             break;
3999         case HCI_STATE_SLEEPING:
4000             err = hci_power_control_state_sleeping(power_mode);
4001             break;
4002         default:
4003             btstack_assert(false);
4004             break;
4005     }
4006     if (err != 0){
4007         return err;
4008     }
4009 
4010     // create internal event
4011 	hci_emit_state();
4012 
4013 	// trigger next/first action
4014 	hci_run();
4015 
4016     return 0;
4017 }
4018 
4019 
4020 #ifdef ENABLE_CLASSIC
4021 
4022 static void hci_update_scan_enable(void){
4023     // 2 = page scan, 1 = inq scan
4024     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4025     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4026     hci_run();
4027 }
4028 
4029 void gap_discoverable_control(uint8_t enable){
4030     if (enable) enable = 1; // normalize argument
4031 
4032     if (hci_stack->discoverable == enable){
4033         hci_emit_discoverable_enabled(hci_stack->discoverable);
4034         return;
4035     }
4036 
4037     hci_stack->discoverable = enable;
4038     hci_update_scan_enable();
4039 }
4040 
4041 void gap_connectable_control(uint8_t enable){
4042     if (enable) enable = 1; // normalize argument
4043 
4044     // don't emit event
4045     if (hci_stack->connectable == enable) return;
4046 
4047     hci_stack->connectable = enable;
4048     hci_update_scan_enable();
4049 }
4050 #endif
4051 
4052 void gap_local_bd_addr(bd_addr_t address_buffer){
4053     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4054 }
4055 
4056 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4057 static void hci_host_num_completed_packets(void){
4058 
4059     // create packet manually as arrays are not supported and num_commands should not get reduced
4060     hci_reserve_packet_buffer();
4061     uint8_t * packet = hci_get_outgoing_packet_buffer();
4062 
4063     uint16_t size = 0;
4064     uint16_t num_handles = 0;
4065     packet[size++] = 0x35;
4066     packet[size++] = 0x0c;
4067     size++;  // skip param len
4068     size++;  // skip num handles
4069 
4070     // add { handle, packets } entries
4071     btstack_linked_item_t * it;
4072     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4073         hci_connection_t * connection = (hci_connection_t *) it;
4074         if (connection->num_packets_completed){
4075             little_endian_store_16(packet, size, connection->con_handle);
4076             size += 2;
4077             little_endian_store_16(packet, size, connection->num_packets_completed);
4078             size += 2;
4079             //
4080             num_handles++;
4081             connection->num_packets_completed = 0;
4082         }
4083     }
4084 
4085     packet[2] = size - 3;
4086     packet[3] = num_handles;
4087 
4088     hci_stack->host_completed_packets = 0;
4089 
4090     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4091     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4092 
4093     // release packet buffer for synchronous transport implementations
4094     if (hci_transport_synchronous()){
4095         hci_release_packet_buffer();
4096         hci_emit_transport_packet_sent();
4097     }
4098 }
4099 #endif
4100 
4101 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4102     UNUSED(ds);
4103     hci_stack->substate = HCI_HALTING_CLOSE;
4104     // allow packet handlers to defer final shutdown
4105     hci_emit_state();
4106     hci_run();
4107 }
4108 
4109 static bool hci_run_acl_fragments(void){
4110     if (hci_stack->acl_fragmentation_total_size > 0u) {
4111         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4112         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4113         if (connection) {
4114             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4115                 hci_send_acl_packet_fragments(connection);
4116                 return true;
4117             }
4118         } else {
4119             // connection gone -> discard further fragments
4120             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4121             hci_stack->acl_fragmentation_total_size = 0;
4122             hci_stack->acl_fragmentation_pos = 0;
4123         }
4124     }
4125     return false;
4126 }
4127 
4128 #ifdef ENABLE_CLASSIC
4129 static bool hci_run_general_gap_classic(void){
4130 
4131     // assert stack is working and classic is active
4132     if (hci_classic_supported() == false)      return false;
4133     if (hci_stack->state != HCI_STATE_WORKING) return false;
4134 
4135     // decline incoming connections
4136     if (hci_stack->decline_reason){
4137         uint8_t reason = hci_stack->decline_reason;
4138         hci_stack->decline_reason = 0;
4139         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4140         return true;
4141     }
4142 
4143     if (hci_stack->gap_tasks != 0){
4144         hci_run_gap_tasks_classic();
4145         return true;
4146     }
4147 
4148     // start/stop inquiry
4149     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4150         uint8_t duration = hci_stack->inquiry_state;
4151         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4152         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4153         return true;
4154     }
4155     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4156         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4157         hci_send_cmd(&hci_inquiry_cancel);
4158         return true;
4159     }
4160     // remote name request
4161     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4162         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4163         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4164                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4165         return true;
4166     }
4167 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4168     // Local OOB data
4169     if (hci_stack->classic_read_local_oob_data){
4170         hci_stack->classic_read_local_oob_data = false;
4171         if (hci_stack->local_supported_commands[1] & 0x10u){
4172             hci_send_cmd(&hci_read_local_extended_oob_data);
4173         } else {
4174             hci_send_cmd(&hci_read_local_oob_data);
4175         }
4176     }
4177 #endif
4178     // pairing
4179     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4180         uint8_t state = hci_stack->gap_pairing_state;
4181         uint8_t pin_code[16];
4182         switch (state){
4183             case GAP_PAIRING_STATE_SEND_PIN:
4184                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4185                 memset(pin_code, 0, 16);
4186                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4187                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4188                 break;
4189             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4190                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4191                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4192                 break;
4193             case GAP_PAIRING_STATE_SEND_PASSKEY:
4194                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4195                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4196                 break;
4197             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4198                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4199                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4200                 break;
4201             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4202                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4203                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4204                 break;
4205             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4206                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4207                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4208                 break;
4209             default:
4210                 break;
4211         }
4212         return true;
4213     }
4214     return false;
4215 }
4216 #endif
4217 
4218 #ifdef ENABLE_BLE
4219 static bool hci_run_general_gap_le(void){
4220 
4221     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4222 
4223     if (hci_stack->state != HCI_STATE_WORKING) return false;
4224     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4225 
4226 
4227     // Phase 1: collect what to stop
4228 
4229     bool scanning_stop = false;
4230     bool connecting_stop = false;
4231     bool advertising_stop = false;
4232 
4233 #ifndef ENABLE_LE_CENTRAL
4234     UNUSED(scanning_stop);
4235     UNUSED(connecting_stop);
4236 #endif
4237 #ifndef ENABLE_LE_PERIPHERAL
4238     UNUSED(advertising_stop);
4239 #endif
4240 
4241     // check if whitelist needs modification
4242     bool whitelist_modification_pending = false;
4243     btstack_linked_list_iterator_t lit;
4244     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4245     while (btstack_linked_list_iterator_has_next(&lit)){
4246         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4247         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4248             whitelist_modification_pending = true;
4249             break;
4250         }
4251     }
4252     // check if resolving list needs modification
4253     bool resolving_list_modification_pending = false;
4254 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4255     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4256 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4257         resolving_list_modification_pending = true;
4258     }
4259 #endif
4260 
4261 #ifdef ENABLE_LE_CENTRAL
4262     // scanning control
4263     if (hci_stack->le_scanning_active) {
4264         // stop if:
4265         // - parameter change required
4266         // - it's disabled
4267         // - whitelist change required but used for scanning
4268         // - resolving list modified
4269         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4270         if ((hci_stack->le_scanning_param_update) ||
4271             !hci_stack->le_scanning_enabled ||
4272             scanning_uses_whitelist ||
4273             resolving_list_modification_pending){
4274 
4275             scanning_stop = true;
4276         }
4277     }
4278 #endif
4279 
4280 #ifdef ENABLE_LE_CENTRAL
4281     // connecting control
4282     bool connecting_with_whitelist;
4283     switch (hci_stack->le_connecting_state){
4284         case LE_CONNECTING_DIRECT:
4285         case LE_CONNECTING_WHITELIST:
4286             // stop connecting if:
4287             // - connecting uses white and whitelist modification pending
4288             // - if it got disabled
4289             // - resolving list modified
4290             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4291             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4292                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4293                 resolving_list_modification_pending) {
4294 
4295                 connecting_stop = true;
4296             }
4297             break;
4298         default:
4299             break;
4300     }
4301 #endif
4302 
4303 #ifdef ENABLE_LE_PERIPHERAL
4304     // le advertisement control
4305     if (hci_stack->le_advertisements_active){
4306         // stop if:
4307         // - parameter change required
4308         // - it's disabled
4309         // - whitelist change required but used for advertisement filter policy
4310         // - resolving list modified
4311         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4312         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4313         if (advertising_change ||
4314             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4315             (advertising_uses_whitelist & whitelist_modification_pending) ||
4316             resolving_list_modification_pending) {
4317 
4318             advertising_stop = true;
4319         }
4320     }
4321 #endif
4322 
4323 
4324     // Phase 2: stop everything that should be off during modifications
4325 
4326 #ifdef ENABLE_LE_CENTRAL
4327     if (scanning_stop){
4328         hci_stack->le_scanning_active = false;
4329         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4330         return true;
4331     }
4332 #endif
4333 
4334 #ifdef ENABLE_LE_CENTRAL
4335     if (connecting_stop){
4336         hci_send_cmd(&hci_le_create_connection_cancel);
4337         return true;
4338     }
4339 #endif
4340 
4341 #ifdef ENABLE_LE_PERIPHERAL
4342     if (advertising_stop){
4343         hci_stack->le_advertisements_active = false;
4344         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4345         return true;
4346     }
4347 #endif
4348 
4349     // Phase 3: modify
4350 
4351 #ifdef ENABLE_LE_CENTRAL
4352     if (hci_stack->le_scanning_param_update){
4353         hci_stack->le_scanning_param_update = false;
4354         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4355                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4356         return true;
4357     }
4358 #endif
4359 
4360 #ifdef ENABLE_LE_PERIPHERAL
4361     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4362         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4363         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4364         hci_send_cmd(&hci_le_set_advertising_parameters,
4365                      hci_stack->le_advertisements_interval_min,
4366                      hci_stack->le_advertisements_interval_max,
4367                      hci_stack->le_advertisements_type,
4368                      hci_stack->le_advertisements_own_addr_type,
4369                      hci_stack->le_advertisements_direct_address_type,
4370                      hci_stack->le_advertisements_direct_address,
4371                      hci_stack->le_advertisements_channel_map,
4372                      hci_stack->le_advertisements_filter_policy);
4373         return true;
4374     }
4375     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4376         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4377         uint8_t adv_data_clean[31];
4378         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4379         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4380                      hci_stack->le_advertisements_data_len);
4381         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4382         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4383         return true;
4384     }
4385     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4386         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4387         uint8_t scan_data_clean[31];
4388         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4389         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4390                      hci_stack->le_scan_response_data_len);
4391         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4392         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4393         return true;
4394     }
4395 #endif
4396 
4397 
4398 #ifdef ENABLE_LE_CENTRAL
4399     // if connect with whitelist was active and is not cancelled yet, wait until next time
4400     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4401 #endif
4402 
4403     // LE Whitelist Management
4404     if (whitelist_modification_pending){
4405         // add/remove entries
4406         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4407         while (btstack_linked_list_iterator_has_next(&lit)){
4408             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4409 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4410 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4411 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4412 				return true;
4413 			}
4414             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4415 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4416                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4417                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4418                 return true;
4419             }
4420             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4421 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4422 				btstack_memory_whitelist_entry_free(entry);
4423             }
4424         }
4425     }
4426 
4427 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4428     // LE Resolving List Management
4429     if (resolving_list_supported) {
4430 		uint16_t i;
4431 		switch (hci_stack->le_resolving_list_state) {
4432 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4433 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4434 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4435 				return true;
4436 			case LE_RESOLVING_LIST_READ_SIZE:
4437 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4438 				hci_send_cmd(&hci_le_read_resolving_list_size);
4439 				return true;
4440 			case LE_RESOLVING_LIST_SEND_CLEAR:
4441 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4442 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4443 							  sizeof(hci_stack->le_resolving_list_add_entries));
4444 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4445 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4446 				hci_send_cmd(&hci_le_clear_resolving_list);
4447 				return true;
4448 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4449 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4450 					uint8_t offset = i >> 3;
4451 					uint8_t mask = 1 << (i & 7);
4452 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4453 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4454 					bd_addr_t peer_identity_addreses;
4455 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4456 					sm_key_t peer_irk;
4457 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4458 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4459 
4460 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4461 					// trigger whitelist entry 'update' (work around for controller bug)
4462 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4463 					while (btstack_linked_list_iterator_has_next(&lit)) {
4464 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4465 						if (entry->address_type != peer_identity_addr_type) continue;
4466 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4467 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4468 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4469 					}
4470 #endif
4471 
4472 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4473 								 peer_identity_addreses);
4474 					return true;
4475 				}
4476 
4477 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4478 
4479 				/* fall through */
4480 
4481 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4482 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4483 					uint8_t offset = i >> 3;
4484 					uint8_t mask = 1 << (i & 7);
4485 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4486 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4487 					bd_addr_t peer_identity_addreses;
4488 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4489 					sm_key_t peer_irk;
4490 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4491 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4492 					const uint8_t *local_irk = gap_get_persistent_irk();
4493 					// command uses format specifier 'P' that stores 16-byte value without flip
4494 					uint8_t local_irk_flipped[16];
4495 					uint8_t peer_irk_flipped[16];
4496 					reverse_128(local_irk, local_irk_flipped);
4497 					reverse_128(peer_irk, peer_irk_flipped);
4498 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4499 								 peer_irk_flipped, local_irk_flipped);
4500 					return true;
4501 				}
4502 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4503 				break;
4504 
4505 			default:
4506 				break;
4507 		}
4508 	}
4509     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4510 #endif
4511 
4512     // Phase 4: restore state
4513 
4514 #ifdef ENABLE_LE_CENTRAL
4515     // re-start scanning
4516     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4517         hci_stack->le_scanning_active = true;
4518         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4519         return true;
4520     }
4521 #endif
4522 
4523 #ifdef ENABLE_LE_CENTRAL
4524     // re-start connecting
4525     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4526         bd_addr_t null_addr;
4527         memset(null_addr, 0, 6);
4528         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4529         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4530         hci_send_cmd(&hci_le_create_connection,
4531                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4532                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4533                      1,         // use whitelist
4534                      0,         // peer address type
4535                      null_addr, // peer bd addr
4536                      hci_stack->le_connection_own_addr_type,   // our addr type:
4537                      hci_stack->le_connection_interval_min,    // conn interval min
4538                      hci_stack->le_connection_interval_max,    // conn interval max
4539                      hci_stack->le_connection_latency,         // conn latency
4540                      hci_stack->le_supervision_timeout,        // conn latency
4541                      hci_stack->le_minimum_ce_length,          // min ce length
4542                      hci_stack->le_maximum_ce_length           // max ce length
4543         );
4544         return true;
4545     }
4546 #endif
4547 
4548 #ifdef ENABLE_LE_PERIPHERAL
4549     // re-start advertising
4550     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4551         // check if advertisements should be enabled given
4552         hci_stack->le_advertisements_active = true;
4553         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4554         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4555         return true;
4556     }
4557 #endif
4558 
4559     return false;
4560 }
4561 #endif
4562 
4563 static bool hci_run_general_pending_commands(void){
4564     btstack_linked_item_t * it;
4565     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4566         hci_connection_t * connection = (hci_connection_t *) it;
4567 
4568         switch(connection->state){
4569             case SEND_CREATE_CONNECTION:
4570                 switch(connection->address_type){
4571 #ifdef ENABLE_CLASSIC
4572                     case BD_ADDR_TYPE_ACL:
4573                         log_info("sending hci_create_connection");
4574                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4575                         break;
4576 #endif
4577                     default:
4578 #ifdef ENABLE_BLE
4579 #ifdef ENABLE_LE_CENTRAL
4580                         log_info("sending hci_le_create_connection");
4581                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4582                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4583                         hci_send_cmd(&hci_le_create_connection,
4584                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4585                                      hci_stack->le_connection_scan_window,      // conn scan windows
4586                                      0,         // don't use whitelist
4587                                      connection->address_type, // peer address type
4588                                      connection->address,      // peer bd addr
4589                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4590                                      hci_stack->le_connection_interval_min,    // conn interval min
4591                                      hci_stack->le_connection_interval_max,    // conn interval max
4592                                      hci_stack->le_connection_latency,         // conn latency
4593                                      hci_stack->le_supervision_timeout,        // conn latency
4594                                      hci_stack->le_minimum_ce_length,          // min ce length
4595                                      hci_stack->le_maximum_ce_length          // max ce length
4596                         );
4597                         connection->state = SENT_CREATE_CONNECTION;
4598 #endif
4599 #endif
4600                         break;
4601                 }
4602                 return true;
4603 
4604 #ifdef ENABLE_CLASSIC
4605             case RECEIVED_CONNECTION_REQUEST:
4606                 connection->role  = HCI_ROLE_SLAVE;
4607                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4608                     log_info("sending hci_accept_connection_request");
4609                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4610                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4611                 }
4612                 return true;
4613 #endif
4614 
4615 #ifdef ENABLE_BLE
4616 #ifdef ENABLE_LE_CENTRAL
4617             case SEND_CANCEL_CONNECTION:
4618                 connection->state = SENT_CANCEL_CONNECTION;
4619                 hci_send_cmd(&hci_le_create_connection_cancel);
4620                 return true;
4621 #endif
4622 #endif
4623             case SEND_DISCONNECT:
4624                 connection->state = SENT_DISCONNECT;
4625                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4626                 return true;
4627 
4628             default:
4629                 break;
4630         }
4631 
4632         // no further commands if connection is about to get shut down
4633         if (connection->state == SENT_DISCONNECT) continue;
4634 
4635         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4636             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4637             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4638             return true;
4639         }
4640 
4641 #ifdef ENABLE_CLASSIC
4642 
4643         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4644             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4645             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4646             return true;
4647         }
4648 
4649         // Handling link key request requires remote supported features
4650         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4651             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4652             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4653 
4654             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4655             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4656             if (have_link_key && security_level_sufficient){
4657                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4658             } else {
4659                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4660             }
4661             return true;
4662         }
4663 
4664         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4665             log_info("denying to pin request");
4666             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4667             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4668             return true;
4669         }
4670 
4671         // security assessment requires remote features
4672         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4673             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4674             hci_ssp_assess_security_on_io_cap_request(connection);
4675             // no return here as hci_ssp_assess_security_on_io_cap_request only sets AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY or AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY
4676         }
4677 
4678         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4679             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4680             // set authentication requirements:
4681             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4682             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4683             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4684             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4685                 authreq |= 1;
4686             }
4687             bool bonding = hci_stack->bondable;
4688             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4689                 // if we have received IO Cap Response, we're in responder role
4690                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4691                 if (bonding && !remote_bonding){
4692                     log_info("Remote not bonding, dropping local flag");
4693                     bonding = false;
4694                 }
4695             }
4696             if (bonding){
4697                 if (connection->bonding_flags & BONDING_DEDICATED){
4698                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4699                 } else {
4700                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4701                 }
4702             }
4703             uint8_t have_oob_data = 0;
4704 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4705             if (connection->classic_oob_c_192 != NULL){
4706                     have_oob_data |= 1;
4707             }
4708             if (connection->classic_oob_c_256 != NULL){
4709                 have_oob_data |= 2;
4710             }
4711 #endif
4712             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4713             return true;
4714         }
4715 
4716         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4717             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4718             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4719             return true;
4720         }
4721 
4722 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4723         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4724             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4725             const uint8_t zero[16] = { 0 };
4726             const uint8_t * r_192 = zero;
4727             const uint8_t * c_192 = zero;
4728             const uint8_t * r_256 = zero;
4729             const uint8_t * c_256 = zero;
4730             // verify P-256 OOB
4731             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4732                 c_256 = connection->classic_oob_c_256;
4733                 if (connection->classic_oob_r_256 != NULL) {
4734                     r_256 = connection->classic_oob_r_256;
4735                 }
4736             }
4737             // verify P-192 OOB
4738             if ((connection->classic_oob_c_192 != NULL)) {
4739                 c_192 = connection->classic_oob_c_192;
4740                 if (connection->classic_oob_r_192 != NULL) {
4741                     r_192 = connection->classic_oob_r_192;
4742                 }
4743             }
4744 
4745             // assess security
4746             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4747             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4748             if (need_level_4 && !can_reach_level_4){
4749                 log_info("Level 4 required, but not possible -> abort");
4750                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4751                 // send oob negative reply
4752                 c_256 = NULL;
4753                 c_192 = NULL;
4754             }
4755 
4756             // Reply
4757             if (c_256 != zero) {
4758                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4759             } else if (c_192 != zero){
4760                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4761             } else {
4762                 hci_stack->classic_oob_con_handle = connection->con_handle;
4763                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4764             }
4765             return true;
4766         }
4767 #endif
4768 
4769         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4770             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4771             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4772             return true;
4773         }
4774 
4775         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4776             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4777             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4778             return true;
4779         }
4780 
4781         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4782             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4783             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4784             return true;
4785         }
4786 
4787         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4788             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4789             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4790             connection->state = SENT_DISCONNECT;
4791             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4792             return true;
4793         }
4794 
4795         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4796             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4797             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4798             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4799             return true;
4800         }
4801 
4802         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4803             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4804             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4805             return true;
4806         }
4807 
4808         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4809             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4810             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4811             return true;
4812         }
4813 
4814         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4815             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4816             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4817             return true;
4818         }
4819 
4820         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4821             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4822             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4823             return true;
4824         }
4825 
4826         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4827             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4828             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4829             return true;
4830         }
4831 #endif
4832 
4833         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4834             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4835 #ifdef ENABLE_CLASSIC
4836             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4837 #endif
4838             if (connection->state != SENT_DISCONNECT){
4839                 connection->state = SENT_DISCONNECT;
4840                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4841                 return true;
4842             }
4843         }
4844 
4845 #ifdef ENABLE_CLASSIC
4846         uint16_t sniff_min_interval;
4847         switch (connection->sniff_min_interval){
4848             case 0:
4849                 break;
4850             case 0xffff:
4851                 connection->sniff_min_interval = 0;
4852                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4853                 return true;
4854             default:
4855                 sniff_min_interval = connection->sniff_min_interval;
4856                 connection->sniff_min_interval = 0;
4857                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4858                 return true;
4859         }
4860 
4861         if (connection->sniff_subrating_max_latency != 0xffff){
4862             uint16_t max_latency = connection->sniff_subrating_max_latency;
4863             connection->sniff_subrating_max_latency = 0;
4864             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4865             return true;
4866         }
4867 
4868         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4869             uint8_t service_type = (uint8_t) connection->qos_service_type;
4870             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4871             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);
4872             return true;
4873         }
4874 
4875         if (connection->request_role != HCI_ROLE_INVALID){
4876             hci_role_t role = connection->request_role;
4877             connection->request_role = HCI_ROLE_INVALID;
4878             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4879             return true;
4880         }
4881 #endif
4882 
4883 #ifdef ENABLE_BLE
4884         switch (connection->le_con_parameter_update_state){
4885             // response to L2CAP CON PARAMETER UPDATE REQUEST
4886             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4887                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4888                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4889                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4890                              0x0000, 0xffff);
4891                 return true;
4892             case CON_PARAMETER_UPDATE_REPLY:
4893                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4894                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4895                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4896                              0x0000, 0xffff);
4897                 return true;
4898             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4899                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4900                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4901                 return true;
4902             default:
4903                 break;
4904         }
4905         if (connection->le_phy_update_all_phys != 0xffu){
4906             uint8_t all_phys = connection->le_phy_update_all_phys;
4907             connection->le_phy_update_all_phys = 0xff;
4908             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);
4909             return true;
4910         }
4911 #endif
4912     }
4913     return false;
4914 }
4915 
4916 static void hci_run(void){
4917 
4918     bool done;
4919 
4920     // send continuation fragments first, as they block the prepared packet buffer
4921     done = hci_run_acl_fragments();
4922     if (done) return;
4923 
4924 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4925     // send host num completed packets next as they don't require num_cmd_packets > 0
4926     if (!hci_can_send_comand_packet_transport()) return;
4927     if (hci_stack->host_completed_packets){
4928         hci_host_num_completed_packets();
4929         return;
4930     }
4931 #endif
4932 
4933     if (!hci_can_send_command_packet_now()) return;
4934 
4935     // global/non-connection oriented commands
4936 
4937 
4938 #ifdef ENABLE_CLASSIC
4939     // general gap classic
4940     done = hci_run_general_gap_classic();
4941     if (done) return;
4942 #endif
4943 
4944 #ifdef ENABLE_BLE
4945     // general gap le
4946     done = hci_run_general_gap_le();
4947     if (done) return;
4948 #endif
4949 
4950     // send pending HCI commands
4951     done = hci_run_general_pending_commands();
4952     if (done) return;
4953 
4954     // stack state sub statemachines
4955     hci_connection_t * connection;
4956     switch (hci_stack->state){
4957         case HCI_STATE_INITIALIZING:
4958             hci_initializing_run();
4959             break;
4960 
4961         case HCI_STATE_HALTING:
4962 
4963             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4964             switch (hci_stack->substate){
4965                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4966                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4967 
4968 #ifdef ENABLE_BLE
4969 #ifdef ENABLE_LE_CENTRAL
4970                     // free whitelist entries
4971                     {
4972                         btstack_linked_list_iterator_t lit;
4973                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4974                         while (btstack_linked_list_iterator_has_next(&lit)){
4975                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4976                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4977                             btstack_memory_whitelist_entry_free(entry);
4978                         }
4979                     }
4980 #endif
4981 #endif
4982                     // close all open connections
4983                     connection =  (hci_connection_t *) hci_stack->connections;
4984                     if (connection){
4985                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4986                         if (!hci_can_send_command_packet_now()) return;
4987 
4988                         // check state
4989                         if (connection->state == SENT_DISCONNECT) return;
4990                         connection->state = SENT_DISCONNECT;
4991 
4992                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4993 
4994                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4995                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4996 
4997                         // ... which would be ignored anyway as we shutdown (free) the connection now
4998                         hci_shutdown_connection(connection);
4999 
5000                         // finally, send the disconnect command
5001                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5002                         return;
5003                     }
5004 
5005                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5006                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5007                         log_info("HCI_STATE_HALTING: wait 50 ms");
5008                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5009                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5010                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5011                         btstack_run_loop_add_timer(&hci_stack->timeout);
5012                         break;
5013                     }
5014 
5015                     /* fall through */
5016 
5017                 case HCI_HALTING_CLOSE:
5018                     log_info("HCI_STATE_HALTING, calling off");
5019 
5020                     // switch mode
5021                     hci_power_control_off();
5022 
5023                     log_info("HCI_STATE_HALTING, emitting state");
5024                     hci_emit_state();
5025                     log_info("HCI_STATE_HALTING, done");
5026                     break;
5027 
5028                 case HCI_HALTING_W4_TIMER:
5029                     // keep waiting
5030 
5031                     break;
5032                 default:
5033                     break;
5034             }
5035 
5036             break;
5037 
5038         case HCI_STATE_FALLING_ASLEEP:
5039             switch(hci_stack->substate) {
5040                 case HCI_FALLING_ASLEEP_DISCONNECT:
5041                     log_info("HCI_STATE_FALLING_ASLEEP");
5042                     // close all open connections
5043                     connection =  (hci_connection_t *) hci_stack->connections;
5044                     if (connection){
5045 
5046                         // send disconnect
5047                         if (!hci_can_send_command_packet_now()) return;
5048 
5049                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5050                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5051 
5052                         // send disconnected event right away - causes higher layer connections to get closed, too.
5053                         hci_shutdown_connection(connection);
5054                         return;
5055                     }
5056 
5057                     if (hci_classic_supported()){
5058                         // disable page and inquiry scan
5059                         if (!hci_can_send_command_packet_now()) return;
5060 
5061                         log_info("HCI_STATE_HALTING, disabling inq scans");
5062                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5063 
5064                         // continue in next sub state
5065                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5066                         break;
5067                     }
5068 
5069                     /* fall through */
5070 
5071                 case HCI_FALLING_ASLEEP_COMPLETE:
5072                     log_info("HCI_STATE_HALTING, calling sleep");
5073                     // switch mode
5074                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5075                     hci_emit_state();
5076                     break;
5077 
5078                 default:
5079                     break;
5080             }
5081             break;
5082 
5083         default:
5084             break;
5085     }
5086 }
5087 
5088 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5089     // house-keeping
5090 
5091 #ifdef ENABLE_CLASSIC
5092     bd_addr_t addr;
5093     hci_connection_t * conn;
5094 #endif
5095 #ifdef ENABLE_LE_CENTRAL
5096     uint8_t initiator_filter_policy;
5097 #endif
5098 
5099     uint16_t opcode = little_endian_read_16(packet, 0);
5100     switch (opcode) {
5101         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5102             hci_stack->loopback_mode = packet[3];
5103             break;
5104 
5105 #ifdef ENABLE_CLASSIC
5106         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5107             reverse_bd_addr(&packet[3], addr);
5108             log_info("Create_connection to %s", bd_addr_to_str(addr));
5109 
5110             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5111             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5112                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5113                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5114             }
5115 
5116             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5117             if (!conn) {
5118                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5119                 if (!conn) {
5120                     // notify client that alloc failed
5121                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5122                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5123                 }
5124                 conn->state = SEND_CREATE_CONNECTION;
5125                 conn->role  = HCI_ROLE_MASTER;
5126             }
5127 
5128             conn->con_handle = HCI_CON_HANDLE_INVALID;
5129             conn->role = HCI_ROLE_INVALID;
5130 
5131             log_info("conn state %u", conn->state);
5132             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5133             switch (conn->state) {
5134                 // if connection active exists
5135                 case OPEN:
5136                     // and OPEN, emit connection complete command
5137                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5138                     // packet not sent to controller
5139                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5140                 case RECEIVED_DISCONNECTION_COMPLETE:
5141                     // create connection triggered in disconnect complete event, let's do it now
5142                     break;
5143                 case SEND_CREATE_CONNECTION:
5144                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5145                     break;
5146                 default:
5147                     // otherwise, just ignore as it is already in the open process
5148                     // packet not sent to controller
5149                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5150             }
5151             conn->state = SENT_CREATE_CONNECTION;
5152 
5153             // track outgoing connection
5154             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5155             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5156             break;
5157         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5158             if (hci_stack->link_key_db) {
5159                 reverse_bd_addr(&packet[3], addr);
5160                 hci_stack->link_key_db->delete_link_key(addr);
5161             }
5162             break;
5163 
5164 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5165         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5166             // setup_synchronous_connection? Voice setting at offset 22
5167             // TODO: compare to current setting if sco connection already active
5168             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5169             break;
5170         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5171             // accept_synchronus_connection? Voice setting at offset 18
5172             // TODO: compare to current setting if sco connection already active
5173             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5174             break;
5175 #endif
5176 #endif
5177 
5178 #ifdef ENABLE_BLE
5179         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5180             hci_stack->le_random_address_set = 1;
5181             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5182             break;
5183 #ifdef ENABLE_LE_PERIPHERAL
5184         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5185             hci_stack->le_advertisements_active = packet[3] != 0;
5186             break;
5187 #endif
5188 #ifdef ENABLE_LE_CENTRAL
5189         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5190             // white list used?
5191             initiator_filter_policy = packet[7];
5192             switch (initiator_filter_policy) {
5193                 case 0:
5194                     // whitelist not used
5195                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5196                     break;
5197                 case 1:
5198                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5199                     break;
5200                 default:
5201                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5202                     break;
5203             }
5204             // track outgoing connection
5205             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5206             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5207             break;
5208         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5209             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5210             break;
5211 #endif
5212 #endif
5213         default:
5214             break;
5215     }
5216 
5217     hci_stack->num_cmd_packets--;
5218 
5219     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5220     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5221     if (err != 0){
5222         return ERROR_CODE_HARDWARE_FAILURE;
5223     }
5224     return ERROR_CODE_SUCCESS;
5225 }
5226 
5227 // disconnect because of security block
5228 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5229     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5230     if (!connection) return;
5231     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5232 }
5233 
5234 
5235 // Configure Secure Simple Pairing
5236 
5237 #ifdef ENABLE_CLASSIC
5238 
5239 // enable will enable SSP during init
5240 void gap_ssp_set_enable(int enable){
5241     hci_stack->ssp_enable = enable;
5242 }
5243 
5244 static int hci_local_ssp_activated(void){
5245     return gap_ssp_supported() && hci_stack->ssp_enable;
5246 }
5247 
5248 // if set, BTstack will respond to io capability request using authentication requirement
5249 void gap_ssp_set_io_capability(int io_capability){
5250     hci_stack->ssp_io_capability = io_capability;
5251 }
5252 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5253     hci_stack->ssp_authentication_requirement = authentication_requirement;
5254 }
5255 
5256 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5257 void gap_ssp_set_auto_accept(int auto_accept){
5258     hci_stack->ssp_auto_accept = auto_accept;
5259 }
5260 
5261 void gap_secure_connections_enable(bool enable){
5262     hci_stack->secure_connections_enable = enable;
5263 }
5264 
5265 #endif
5266 
5267 // va_list part of hci_send_cmd
5268 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5269     if (!hci_can_send_command_packet_now()){
5270         log_error("hci_send_cmd called but cannot send packet now");
5271         return ERROR_CODE_COMMAND_DISALLOWED;
5272     }
5273 
5274     // for HCI INITIALIZATION
5275     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5276     hci_stack->last_cmd_opcode = cmd->opcode;
5277 
5278     hci_reserve_packet_buffer();
5279     uint8_t * packet = hci_stack->hci_packet_buffer;
5280     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5281     uint8_t status = hci_send_cmd_packet(packet, size);
5282 
5283     // release packet buffer on error or for synchronous transport implementations
5284     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5285         hci_release_packet_buffer();
5286         hci_emit_transport_packet_sent();
5287     }
5288 
5289     return status;
5290 }
5291 
5292 /**
5293  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5294  */
5295 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5296     va_list argptr;
5297     va_start(argptr, cmd);
5298     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5299     va_end(argptr);
5300     return status;
5301 }
5302 
5303 // Create various non-HCI events.
5304 // TODO: generalize, use table similar to hci_create_command
5305 
5306 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5307     // dump packet
5308     if (dump) {
5309         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5310     }
5311 
5312     // dispatch to all event handlers
5313     btstack_linked_list_iterator_t it;
5314     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5315     while (btstack_linked_list_iterator_has_next(&it)){
5316         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5317         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5318     }
5319 }
5320 
5321 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5322     if (!hci_stack->acl_packet_handler) return;
5323     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5324 }
5325 
5326 #ifdef ENABLE_CLASSIC
5327 static void hci_notify_if_sco_can_send_now(void){
5328     // notify SCO sender if waiting
5329     if (!hci_stack->sco_waiting_for_can_send_now) return;
5330     if (hci_can_send_sco_packet_now()){
5331         hci_stack->sco_waiting_for_can_send_now = 0;
5332         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5333         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5334         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5335     }
5336 }
5337 
5338 // parsing end emitting has been merged to reduce code size
5339 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5340     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5341 
5342     uint8_t * eir_data;
5343     ad_context_t context;
5344     const uint8_t * name;
5345     uint8_t         name_len;
5346 
5347     if (size < 3) return;
5348 
5349     int event_type = hci_event_packet_get_type(packet);
5350     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5351     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5352 
5353     switch (event_type){
5354         case HCI_EVENT_INQUIRY_RESULT:
5355         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5356             if (size != (3 + (num_responses * 14))) return;
5357             break;
5358         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5359             if (size != 257) return;
5360             if (num_responses != 1) return;
5361             break;
5362         default:
5363             return;
5364     }
5365 
5366     // event[1] is set at the end
5367     int i;
5368     for (i=0; i<num_responses;i++){
5369         memset(event, 0, sizeof(event));
5370         event[0] = GAP_EVENT_INQUIRY_RESULT;
5371         uint8_t event_size = 27;    // if name is not set by EIR
5372 
5373         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5374         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5375         (void)memcpy(&event[9],
5376                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5377                      3); // class of device
5378         (void)memcpy(&event[12],
5379                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5380                      2); // clock offset
5381 
5382         switch (event_type){
5383             case HCI_EVENT_INQUIRY_RESULT:
5384                 // 14,15,16,17 = 0, size 18
5385                 break;
5386             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5387                 event[14] = 1;
5388                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5389                 // 16,17 = 0, size 18
5390                 break;
5391             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5392                 event[14] = 1;
5393                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5394                 // EIR packets only contain a single inquiry response
5395                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5396                 name = NULL;
5397                 // Iterate over EIR data
5398                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5399                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5400                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5401                     const uint8_t * data = ad_iterator_get_data(&context);
5402                     // Prefer Complete Local Name over Shortened Local Name
5403                     switch (data_type){
5404                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5405                             if (name) continue;
5406                             /* fall through */
5407                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5408                             name = data;
5409                             name_len = data_size;
5410                             break;
5411                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5412                             if (data_size != 8) break;
5413                             event[16] = 1;
5414                             memcpy(&event[17], data, 8);
5415                             break;
5416                         default:
5417                             break;
5418                     }
5419                 }
5420                 if (name){
5421                     event[25] = 1;
5422                     // truncate name if needed
5423                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5424                     event[26] = len;
5425                     (void)memcpy(&event[27], name, len);
5426                     event_size += len;
5427                 }
5428                 break;
5429             default:
5430                 return;
5431         }
5432         event[1] = event_size - 2;
5433         hci_emit_event(event, event_size, 1);
5434     }
5435 }
5436 #endif
5437 
5438 void hci_emit_state(void){
5439     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5440     uint8_t event[3];
5441     event[0] = BTSTACK_EVENT_STATE;
5442     event[1] = sizeof(event) - 2u;
5443     event[2] = hci_stack->state;
5444     hci_emit_event(event, sizeof(event), 1);
5445 }
5446 
5447 #ifdef ENABLE_CLASSIC
5448 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5449     uint8_t event[13];
5450     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5451     event[1] = sizeof(event) - 2;
5452     event[2] = status;
5453     little_endian_store_16(event, 3, con_handle);
5454     reverse_bd_addr(address, &event[5]);
5455     event[11] = 1; // ACL connection
5456     event[12] = 0; // encryption disabled
5457     hci_emit_event(event, sizeof(event), 1);
5458 }
5459 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5460     if (disable_l2cap_timeouts) return;
5461     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5462     uint8_t event[4];
5463     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5464     event[1] = sizeof(event) - 2;
5465     little_endian_store_16(event, 2, conn->con_handle);
5466     hci_emit_event(event, sizeof(event), 1);
5467 }
5468 #endif
5469 
5470 #ifdef ENABLE_BLE
5471 #ifdef ENABLE_LE_CENTRAL
5472 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){
5473     uint8_t event[21];
5474     event[0] = HCI_EVENT_LE_META;
5475     event[1] = sizeof(event) - 2u;
5476     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5477     event[3] = status;
5478     little_endian_store_16(event, 4, con_handle);
5479     event[6] = 0; // TODO: role
5480     event[7] = address_type;
5481     reverse_bd_addr(address, &event[8]);
5482     little_endian_store_16(event, 14, 0); // interval
5483     little_endian_store_16(event, 16, 0); // latency
5484     little_endian_store_16(event, 18, 0); // supervision timeout
5485     event[20] = 0; // master clock accuracy
5486     hci_emit_event(event, sizeof(event), 1);
5487 }
5488 #endif
5489 #endif
5490 
5491 static void hci_emit_transport_packet_sent(void){
5492     // notify upper stack that it might be possible to send again
5493     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5494     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5495 }
5496 
5497 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5498     uint8_t event[6];
5499     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5500     event[1] = sizeof(event) - 2u;
5501     event[2] = 0; // status = OK
5502     little_endian_store_16(event, 3, con_handle);
5503     event[5] = reason;
5504     hci_emit_event(event, sizeof(event), 1);
5505 }
5506 
5507 static void hci_emit_nr_connections_changed(void){
5508     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5509     uint8_t event[3];
5510     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5511     event[1] = sizeof(event) - 2u;
5512     event[2] = nr_hci_connections();
5513     hci_emit_event(event, sizeof(event), 1);
5514 }
5515 
5516 static void hci_emit_hci_open_failed(void){
5517     log_info("BTSTACK_EVENT_POWERON_FAILED");
5518     uint8_t event[2];
5519     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5520     event[1] = sizeof(event) - 2u;
5521     hci_emit_event(event, sizeof(event), 1);
5522 }
5523 
5524 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5525     log_info("hci_emit_dedicated_bonding_result %u ", status);
5526     uint8_t event[9];
5527     int pos = 0;
5528     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5529     event[pos++] = sizeof(event) - 2u;
5530     event[pos++] = status;
5531     reverse_bd_addr(address, &event[pos]);
5532     hci_emit_event(event, sizeof(event), 1);
5533 }
5534 
5535 
5536 #ifdef ENABLE_CLASSIC
5537 
5538 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5539     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5540     uint8_t event[5];
5541     int pos = 0;
5542     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5543     event[pos++] = sizeof(event) - 2;
5544     little_endian_store_16(event, 2, con_handle);
5545     pos += 2;
5546     event[pos++] = level;
5547     hci_emit_event(event, sizeof(event), 1);
5548 }
5549 
5550 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5551     if (!connection) return LEVEL_0;
5552     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5553     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5554     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5555     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5556     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5557     // LEVEL 4 always requires 128 bit encrytion key size
5558     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5559         security_level = LEVEL_3;
5560     }
5561     return security_level;
5562 }
5563 
5564 static void hci_emit_discoverable_enabled(uint8_t enabled){
5565     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5566     uint8_t event[3];
5567     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5568     event[1] = sizeof(event) - 2;
5569     event[2] = enabled;
5570     hci_emit_event(event, sizeof(event), 1);
5571 }
5572 
5573 // query if remote side supports eSCO
5574 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5575     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5576     if (!connection) return false;
5577     return (connection->remote_supported_features[0] & 1) != 0;
5578 }
5579 
5580 static bool hci_ssp_supported(hci_connection_t * connection){
5581     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5582     return (connection->bonding_flags & mask) == mask;
5583 }
5584 
5585 // query if remote side supports SSP
5586 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5587     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5588     if (!connection) return false;
5589     return hci_ssp_supported(connection) ? 1 : 0;
5590 }
5591 
5592 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5593     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5594 }
5595 
5596 /**
5597  * Check if remote supported features query has completed
5598  */
5599 bool hci_remote_features_available(hci_con_handle_t handle){
5600     hci_connection_t * connection = hci_connection_for_handle(handle);
5601     if (!connection) return false;
5602     return (connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0;
5603 }
5604 
5605 // GAP API
5606 /**
5607  * @bbrief enable/disable bonding. default is enabled
5608  * @praram enabled
5609  */
5610 void gap_set_bondable_mode(int enable){
5611     hci_stack->bondable = enable ? 1 : 0;
5612 }
5613 /**
5614  * @brief Get bondable mode.
5615  * @return 1 if bondable
5616  */
5617 int gap_get_bondable_mode(void){
5618     return hci_stack->bondable;
5619 }
5620 
5621 /**
5622  * @brief map link keys to security levels
5623  */
5624 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5625     switch (link_key_type){
5626         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5627             return LEVEL_4;
5628         case COMBINATION_KEY:
5629         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5630             return LEVEL_3;
5631         default:
5632             return LEVEL_2;
5633     }
5634 }
5635 
5636 /**
5637  * @brief map link keys to secure connection yes/no
5638  */
5639 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5640     switch (link_key_type){
5641         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5642         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5643             return 1;
5644         default:
5645             return 0;
5646     }
5647 }
5648 
5649 /**
5650  * @brief map link keys to authenticated
5651  */
5652 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5653     switch (link_key_type){
5654         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5655         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5656             return 1;
5657         default:
5658             return 0;
5659     }
5660 }
5661 
5662 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5663     log_info("gap_mitm_protection_required_for_security_level %u", level);
5664     return level > LEVEL_2;
5665 }
5666 
5667 /**
5668  * @brief get current security level
5669  */
5670 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5671     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5672     if (!connection) return LEVEL_0;
5673     return gap_security_level_for_connection(connection);
5674 }
5675 
5676 /**
5677  * @brief request connection to device to
5678  * @result GAP_AUTHENTICATION_RESULT
5679  */
5680 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5681     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5682     if (!connection){
5683         hci_emit_security_level(con_handle, LEVEL_0);
5684         return;
5685     }
5686 
5687     btstack_assert(hci_is_le_connection(connection) == false);
5688 
5689     // Core Spec 5.2, GAP 5.2.2: "When in Secure Connections Only mode, all services (except those allowed to have Security Mode 4, Level 0)
5690     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5691     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5692         requested_level = LEVEL_4;
5693     }
5694 
5695     gap_security_level_t current_level = gap_security_level(con_handle);
5696     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5697         requested_level, connection->requested_security_level, current_level);
5698 
5699     // authentication active if authentication request was sent or planned level > 0
5700     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5701     if (authentication_active){
5702         // authentication already active
5703         if (connection->requested_security_level < requested_level){
5704             // increase requested level as new level is higher
5705             // TODO: handle re-authentication when done
5706             connection->requested_security_level = requested_level;
5707         }
5708     } else {
5709         // no request active, notify if security sufficient
5710         if (requested_level <= current_level){
5711             hci_emit_security_level(con_handle, current_level);
5712             return;
5713         }
5714 
5715         // store request
5716         connection->requested_security_level = requested_level;
5717 
5718         // start to authenticate connection
5719         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5720         hci_run();
5721     }
5722 }
5723 
5724 /**
5725  * @brief start dedicated bonding with device. disconnect after bonding
5726  * @param device
5727  * @param request MITM protection
5728  * @result GAP_DEDICATED_BONDING_COMPLETE
5729  */
5730 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5731 
5732     // create connection state machine
5733     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5734 
5735     if (!connection){
5736         return BTSTACK_MEMORY_ALLOC_FAILED;
5737     }
5738 
5739     // delete linkn key
5740     gap_drop_link_key_for_bd_addr(device);
5741 
5742     // configure LEVEL_2/3, dedicated bonding
5743     connection->state = SEND_CREATE_CONNECTION;
5744     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5745     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5746     connection->bonding_flags = BONDING_DEDICATED;
5747 
5748     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5749 
5750     // handle: connnection failure (connection complete != ok)
5751     // handle: authentication failure
5752     // handle: disconnect on done
5753 
5754     hci_run();
5755 
5756     return 0;
5757 }
5758 
5759 void gap_set_local_name(const char * local_name){
5760     hci_stack->local_name = local_name;
5761     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5762     // also update EIR if not set by user
5763     if (hci_stack->eir_data == NULL){
5764         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5765     }
5766     hci_run();
5767 }
5768 #endif
5769 
5770 
5771 #ifdef ENABLE_BLE
5772 
5773 #ifdef ENABLE_LE_CENTRAL
5774 void gap_start_scan(void){
5775     hci_stack->le_scanning_enabled = true;
5776     hci_run();
5777 }
5778 
5779 void gap_stop_scan(void){
5780     hci_stack->le_scanning_enabled = false;
5781     hci_run();
5782 }
5783 
5784 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5785     hci_stack->le_scan_type          = scan_type;
5786     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5787     hci_stack->le_scan_interval      = scan_interval;
5788     hci_stack->le_scan_window        = scan_window;
5789     hci_stack->le_scanning_param_update = true;
5790     hci_run();
5791 }
5792 
5793 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5794     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5795 }
5796 
5797 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5798     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5799     if (!conn){
5800         // disallow if le connection is already outgoing
5801         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5802             log_error("le connection already active");
5803             return ERROR_CODE_COMMAND_DISALLOWED;
5804         }
5805 
5806         log_info("gap_connect: no connection exists yet, creating context");
5807         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5808         if (!conn){
5809             // notify client that alloc failed
5810             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5811             log_info("gap_connect: failed to alloc hci_connection_t");
5812             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5813         }
5814 
5815         // set le connecting state
5816         if (hci_is_le_connection_type(addr_type)){
5817             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5818         }
5819 
5820         conn->state = SEND_CREATE_CONNECTION;
5821         log_info("gap_connect: send create connection next");
5822         hci_run();
5823         return ERROR_CODE_SUCCESS;
5824     }
5825 
5826     if (!hci_is_le_connection(conn) ||
5827         (conn->state == SEND_CREATE_CONNECTION) ||
5828         (conn->state == SENT_CREATE_CONNECTION)) {
5829         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5830         log_error("gap_connect: classic connection or connect is already being created");
5831         return GATT_CLIENT_IN_WRONG_STATE;
5832     }
5833 
5834     // check if connection was just disconnected
5835     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5836         log_info("gap_connect: send create connection (again)");
5837         conn->state = SEND_CREATE_CONNECTION;
5838         hci_run();
5839         return ERROR_CODE_SUCCESS;
5840     }
5841 
5842     log_info("gap_connect: context exists with state %u", conn->state);
5843     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5844     hci_run();
5845     return ERROR_CODE_SUCCESS;
5846 }
5847 
5848 // @assumption: only a single outgoing LE Connection exists
5849 static hci_connection_t * gap_get_outgoing_connection(void){
5850     btstack_linked_item_t *it;
5851     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5852         hci_connection_t * conn = (hci_connection_t *) it;
5853         if (!hci_is_le_connection(conn)) continue;
5854         switch (conn->state){
5855             case SEND_CREATE_CONNECTION:
5856             case SENT_CREATE_CONNECTION:
5857             case SENT_CANCEL_CONNECTION:
5858                 return conn;
5859             default:
5860                 break;
5861         };
5862     }
5863     return NULL;
5864 }
5865 
5866 uint8_t gap_connect_cancel(void){
5867     hci_connection_t * conn = gap_get_outgoing_connection();
5868     if (!conn) return 0;
5869     switch (conn->state){
5870         case SEND_CREATE_CONNECTION:
5871             // skip sending create connection and emit event instead
5872             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5873             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5874             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5875             btstack_memory_hci_connection_free( conn );
5876             break;
5877         case SENT_CREATE_CONNECTION:
5878             // request to send cancel connection
5879             conn->state = SEND_CANCEL_CONNECTION;
5880             hci_run();
5881             break;
5882         default:
5883             break;
5884     }
5885     return 0;
5886 }
5887 #endif
5888 
5889 #ifdef ENABLE_LE_CENTRAL
5890 /**
5891  * @brief Set connection parameters for outgoing connections
5892  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5893  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5894  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5895  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5896  * @param conn_latency, default: 4
5897  * @param supervision_timeout (unit: 10ms), default: 720 ms
5898  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5899  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5900  */
5901 
5902 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5903     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5904     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5905     hci_stack->le_connection_scan_interval = conn_scan_interval;
5906     hci_stack->le_connection_scan_window = conn_scan_window;
5907     hci_stack->le_connection_interval_min = conn_interval_min;
5908     hci_stack->le_connection_interval_max = conn_interval_max;
5909     hci_stack->le_connection_latency = conn_latency;
5910     hci_stack->le_supervision_timeout = supervision_timeout;
5911     hci_stack->le_minimum_ce_length = min_ce_length;
5912     hci_stack->le_maximum_ce_length = max_ce_length;
5913 }
5914 #endif
5915 
5916 /**
5917  * @brief Updates the connection parameters for a given LE connection
5918  * @param handle
5919  * @param conn_interval_min (unit: 1.25ms)
5920  * @param conn_interval_max (unit: 1.25ms)
5921  * @param conn_latency
5922  * @param supervision_timeout (unit: 10ms)
5923  * @returns 0 if ok
5924  */
5925 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5926     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5927     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5928     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5929     connection->le_conn_interval_min = conn_interval_min;
5930     connection->le_conn_interval_max = conn_interval_max;
5931     connection->le_conn_latency = conn_latency;
5932     connection->le_supervision_timeout = supervision_timeout;
5933     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5934     hci_run();
5935     return 0;
5936 }
5937 
5938 /**
5939  * @brief Request an update of the connection parameter for a given LE connection
5940  * @param handle
5941  * @param conn_interval_min (unit: 1.25ms)
5942  * @param conn_interval_max (unit: 1.25ms)
5943  * @param conn_latency
5944  * @param supervision_timeout (unit: 10ms)
5945  * @returns 0 if ok
5946  */
5947 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5948     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5949     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5950     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5951     connection->le_conn_interval_min = conn_interval_min;
5952     connection->le_conn_interval_max = conn_interval_max;
5953     connection->le_conn_latency = conn_latency;
5954     connection->le_supervision_timeout = supervision_timeout;
5955     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5956     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5957     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5958     return 0;
5959 }
5960 
5961 #ifdef ENABLE_LE_PERIPHERAL
5962 
5963 /**
5964  * @brief Set Advertisement Data
5965  * @param advertising_data_length
5966  * @param advertising_data (max 31 octets)
5967  * @note data is not copied, pointer has to stay valid
5968  */
5969 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5970     hci_stack->le_advertisements_data_len = advertising_data_length;
5971     hci_stack->le_advertisements_data = advertising_data;
5972     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5973     hci_run();
5974 }
5975 
5976 /**
5977  * @brief Set Scan Response Data
5978  * @param advertising_data_length
5979  * @param advertising_data (max 31 octets)
5980  * @note data is not copied, pointer has to stay valid
5981  */
5982 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5983     hci_stack->le_scan_response_data_len = scan_response_data_length;
5984     hci_stack->le_scan_response_data = scan_response_data;
5985     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5986     hci_run();
5987 }
5988 
5989 /**
5990  * @brief Set Advertisement Parameters
5991  * @param adv_int_min
5992  * @param adv_int_max
5993  * @param adv_type
5994  * @param direct_address_type
5995  * @param direct_address
5996  * @param channel_map
5997  * @param filter_policy
5998  *
5999  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6000  */
6001  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6002     uint8_t direct_address_typ, bd_addr_t direct_address,
6003     uint8_t channel_map, uint8_t filter_policy) {
6004 
6005     hci_stack->le_advertisements_interval_min = adv_int_min;
6006     hci_stack->le_advertisements_interval_max = adv_int_max;
6007     hci_stack->le_advertisements_type = adv_type;
6008     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6009     hci_stack->le_advertisements_channel_map = channel_map;
6010     hci_stack->le_advertisements_filter_policy = filter_policy;
6011     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6012                  6);
6013 
6014     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6015     hci_run();
6016  }
6017 
6018 /**
6019  * @brief Enable/Disable Advertisements
6020  * @param enabled
6021  */
6022 void gap_advertisements_enable(int enabled){
6023     hci_stack->le_advertisements_enabled = enabled != 0;
6024     hci_update_advertisements_enabled_for_current_roles();
6025     hci_run();
6026 }
6027 
6028 #endif
6029 
6030 void hci_le_set_own_address_type(uint8_t own_address_type){
6031     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6032     if (own_address_type == hci_stack->le_own_addr_type) return;
6033     hci_stack->le_own_addr_type = own_address_type;
6034 
6035 #ifdef ENABLE_LE_PERIPHERAL
6036     // update advertisement parameters, too
6037     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6038     hci_run();
6039 #endif
6040 #ifdef ENABLE_LE_CENTRAL
6041     // note: we don't update scan parameters or modify ongoing connection attempts
6042 #endif
6043 }
6044 
6045 #endif
6046 
6047 uint8_t gap_disconnect(hci_con_handle_t handle){
6048     hci_connection_t * conn = hci_connection_for_handle(handle);
6049     if (!conn){
6050         hci_emit_disconnection_complete(handle, 0);
6051         return 0;
6052     }
6053     // ignore if already disconnected
6054     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6055         return 0;
6056     }
6057     conn->state = SEND_DISCONNECT;
6058     hci_run();
6059     return 0;
6060 }
6061 
6062 int gap_read_rssi(hci_con_handle_t con_handle){
6063     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6064     if (hci_connection == NULL) return 0;
6065     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6066     hci_run();
6067     return 1;
6068 }
6069 
6070 /**
6071  * @brief Get connection type
6072  * @param con_handle
6073  * @result connection_type
6074  */
6075 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6076     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6077     if (!conn) return GAP_CONNECTION_INVALID;
6078     switch (conn->address_type){
6079         case BD_ADDR_TYPE_LE_PUBLIC:
6080         case BD_ADDR_TYPE_LE_RANDOM:
6081             return GAP_CONNECTION_LE;
6082         case BD_ADDR_TYPE_SCO:
6083             return GAP_CONNECTION_SCO;
6084         case BD_ADDR_TYPE_ACL:
6085             return GAP_CONNECTION_ACL;
6086         default:
6087             return GAP_CONNECTION_INVALID;
6088     }
6089 }
6090 
6091 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6092     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6093     if (!conn) return HCI_ROLE_INVALID;
6094     return (hci_role_t) conn->role;
6095 }
6096 
6097 
6098 #ifdef ENABLE_CLASSIC
6099 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6100     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6101     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6102     conn->request_role = role;
6103     hci_run();
6104     return ERROR_CODE_SUCCESS;
6105 }
6106 #endif
6107 
6108 #ifdef ENABLE_BLE
6109 
6110 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){
6111     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6112     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6113 
6114     conn->le_phy_update_all_phys    = all_phys;
6115     conn->le_phy_update_tx_phys     = tx_phys;
6116     conn->le_phy_update_rx_phys     = rx_phys;
6117     conn->le_phy_update_phy_options = phy_options;
6118 
6119     hci_run();
6120 
6121     return 0;
6122 }
6123 
6124 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6125     // check if already in list
6126     btstack_linked_list_iterator_t it;
6127     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6128     while (btstack_linked_list_iterator_has_next(&it)) {
6129         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6130         if (entry->address_type != address_type) {
6131             continue;
6132         }
6133         if (memcmp(entry->address, address, 6) != 0) {
6134             continue;
6135         }
6136 		// disallow if already scheduled to add
6137 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6138 			return ERROR_CODE_COMMAND_DISALLOWED;
6139 		}
6140 		// still on controller, but scheduled to remove -> re-add
6141 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6142 		return ERROR_CODE_SUCCESS;
6143     }
6144     // alloc and add to list
6145     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6146     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6147     entry->address_type = address_type;
6148     (void)memcpy(entry->address, address, 6);
6149     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6150     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6151     return ERROR_CODE_SUCCESS;
6152 }
6153 
6154 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6155     btstack_linked_list_iterator_t it;
6156     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6157     while (btstack_linked_list_iterator_has_next(&it)){
6158         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6159         if (entry->address_type != address_type) {
6160             continue;
6161         }
6162         if (memcmp(entry->address, address, 6) != 0) {
6163             continue;
6164         }
6165         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6166             // remove from controller if already present
6167             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6168         }  else {
6169             // directly remove entry from whitelist
6170             btstack_linked_list_iterator_remove(&it);
6171             btstack_memory_whitelist_entry_free(entry);
6172         }
6173         return ERROR_CODE_SUCCESS;
6174     }
6175     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6176 }
6177 
6178 static void hci_whitelist_clear(void){
6179     btstack_linked_list_iterator_t it;
6180     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6181     while (btstack_linked_list_iterator_has_next(&it)){
6182         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6183         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6184             // remove from controller if already present
6185             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6186             continue;
6187         }
6188         // directly remove entry from whitelist
6189         btstack_linked_list_iterator_remove(&it);
6190         btstack_memory_whitelist_entry_free(entry);
6191     }
6192 }
6193 
6194 /**
6195  * @brief Clear Whitelist
6196  * @returns 0 if ok
6197  */
6198 uint8_t gap_whitelist_clear(void){
6199     hci_whitelist_clear();
6200     hci_run();
6201     return ERROR_CODE_SUCCESS;
6202 }
6203 
6204 /**
6205  * @brief Add Device to Whitelist
6206  * @param address_typ
6207  * @param address
6208  * @returns 0 if ok
6209  */
6210 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6211     uint8_t status = hci_whitelist_add(address_type, address);
6212     if (status){
6213         return status;
6214     }
6215     hci_run();
6216     return ERROR_CODE_SUCCESS;
6217 }
6218 
6219 /**
6220  * @brief Remove Device from Whitelist
6221  * @param address_typ
6222  * @param address
6223  * @returns 0 if ok
6224  */
6225 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6226     uint8_t status = hci_whitelist_remove(address_type, address);
6227     if (status){
6228         return status;
6229     }
6230     hci_run();
6231     return ERROR_CODE_SUCCESS;
6232 }
6233 
6234 #ifdef ENABLE_LE_CENTRAL
6235 /**
6236  *  @brief Connect with Whitelist
6237  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6238  *  @returns - if ok
6239  */
6240 uint8_t gap_connect_with_whitelist(void){
6241     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6242         return ERROR_CODE_COMMAND_DISALLOWED;
6243     }
6244     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6245     hci_run();
6246     return ERROR_CODE_SUCCESS;
6247 }
6248 
6249 /**
6250  * @brief Auto Connection Establishment - Start Connecting to device
6251  * @param address_typ
6252  * @param address
6253  * @returns 0 if ok
6254  */
6255 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6256     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6257         return ERROR_CODE_COMMAND_DISALLOWED;
6258     }
6259 
6260     uint8_t status = hci_whitelist_add(address_type, address);
6261     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6262         return status;
6263     }
6264 
6265     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6266 
6267     hci_run();
6268     return ERROR_CODE_SUCCESS;
6269 }
6270 
6271 /**
6272  * @brief Auto Connection Establishment - Stop Connecting to device
6273  * @param address_typ
6274  * @param address
6275  * @returns 0 if ok
6276  */
6277 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6278     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6279         return ERROR_CODE_COMMAND_DISALLOWED;
6280     }
6281 
6282     hci_whitelist_remove(address_type, address);
6283     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6284         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6285     }
6286     hci_run();
6287     return 0;
6288 }
6289 
6290 /**
6291  * @brief Auto Connection Establishment - Stop everything
6292  * @note  Convenience function to stop all active auto connection attempts
6293  */
6294 uint8_t gap_auto_connection_stop_all(void){
6295     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6296         return ERROR_CODE_COMMAND_DISALLOWED;
6297     }
6298     hci_whitelist_clear();
6299     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6300     hci_run();
6301     return ERROR_CODE_SUCCESS;
6302 }
6303 
6304 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6305     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6306     if (!conn) return 0;
6307     return conn->le_connection_interval;
6308 }
6309 #endif
6310 #endif
6311 
6312 #ifdef ENABLE_CLASSIC
6313 /**
6314  * @brief Set Extended Inquiry Response data
6315  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6316  * @note has to be done before stack starts up
6317  */
6318 void gap_set_extended_inquiry_response(const uint8_t * data){
6319     hci_stack->eir_data = data;
6320     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6321     hci_run();
6322 }
6323 
6324 /**
6325  * @brief Start GAP Classic Inquiry
6326  * @param duration in 1.28s units
6327  * @return 0 if ok
6328  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6329  */
6330 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6331     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6332     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6333     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6334         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6335     }
6336     hci_stack->inquiry_state = duration_in_1280ms_units;
6337     hci_run();
6338     return 0;
6339 }
6340 
6341 /**
6342  * @brief Stop GAP Classic Inquiry
6343  * @returns 0 if ok
6344  */
6345 int gap_inquiry_stop(void){
6346     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6347         // emit inquiry complete event, before it even started
6348         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6349         hci_emit_event(event, sizeof(event), 1);
6350         return 0;
6351     }
6352     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6353     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6354     hci_run();
6355     return 0;
6356 }
6357 
6358 void gap_inquiry_set_lap(uint32_t lap){
6359     hci_stack->inquiry_lap = lap;
6360 }
6361 
6362 
6363 /**
6364  * @brief Remote Name Request
6365  * @param addr
6366  * @param page_scan_repetition_mode
6367  * @param clock_offset only used when bit 15 is set
6368  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6369  */
6370 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6371     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6372     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6373     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6374     hci_stack->remote_name_clock_offset = clock_offset;
6375     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6376     hci_run();
6377     return 0;
6378 }
6379 
6380 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6381     hci_stack->gap_pairing_state = state;
6382     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6383     hci_run();
6384     return 0;
6385 }
6386 
6387 /**
6388  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6389  * @param addr
6390  * @param pin_data
6391  * @param pin_len
6392  * @return 0 if ok
6393  */
6394 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6395     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6396     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6397     hci_stack->gap_pairing_pin_len = pin_len;
6398     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6399 }
6400 
6401 /**
6402  * @brief Legacy Pairing Pin Code Response
6403  * @param addr
6404  * @param pin
6405  * @return 0 if ok
6406  */
6407 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6408     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6409 }
6410 
6411 /**
6412  * @brief Abort Legacy Pairing
6413  * @param addr
6414  * @param pin
6415  * @return 0 if ok
6416  */
6417 int gap_pin_code_negative(bd_addr_t addr){
6418     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6419     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6420 }
6421 
6422 /**
6423  * @brief SSP Passkey Response
6424  * @param addr
6425  * @param passkey
6426  * @return 0 if ok
6427  */
6428 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6429     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6430     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6431     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6432 }
6433 
6434 /**
6435  * @brief Abort SSP Passkey Entry/Pairing
6436  * @param addr
6437  * @param pin
6438  * @return 0 if ok
6439  */
6440 int gap_ssp_passkey_negative(const bd_addr_t addr){
6441     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6442     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6443 }
6444 
6445 /**
6446  * @brief Accept SSP Numeric Comparison
6447  * @param addr
6448  * @param passkey
6449  * @return 0 if ok
6450  */
6451 int gap_ssp_confirmation_response(const bd_addr_t addr){
6452     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6453     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6454 }
6455 
6456 /**
6457  * @brief Abort SSP Numeric Comparison/Pairing
6458  * @param addr
6459  * @param pin
6460  * @return 0 if ok
6461  */
6462 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6463     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6464     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6465 }
6466 
6467 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6468 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6469     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6470     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6471     connectionSetAuthenticationFlags(conn, flag);
6472     hci_run();
6473     return ERROR_CODE_SUCCESS;
6474 }
6475 #endif
6476 
6477 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6478 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6479     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6480 }
6481 
6482 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6483     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6484 }
6485 #endif
6486 
6487 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6488 /**
6489  * @brief Report Remote OOB Data
6490  * @param bd_addr
6491  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6492  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6493  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6494  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6495  */
6496 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){
6497     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6498     if (connection == NULL) {
6499         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6500     }
6501     connection->classic_oob_c_192 = c_192;
6502     connection->classic_oob_r_192 = r_192;
6503 
6504     // ignore P-256 if not supported by us
6505     if (hci_stack->secure_connections_active){
6506         connection->classic_oob_c_256 = c_256;
6507         connection->classic_oob_r_256 = r_256;
6508     }
6509 
6510     return ERROR_CODE_SUCCESS;
6511 }
6512 /**
6513  * @brief Generate new OOB data
6514  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6515  */
6516 void gap_ssp_generate_oob_data(void){
6517     hci_stack->classic_read_local_oob_data = true;
6518     hci_run();
6519 }
6520 
6521 #endif
6522 
6523 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6524 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6525     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6526     if (connection == NULL) {
6527         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6528     }
6529 
6530     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6531     connection->link_key_type = type;
6532 
6533     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6534 }
6535 
6536 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6537 /**
6538  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6539  * @param inquiry_mode see bluetooth_defines.h
6540  */
6541 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6542     hci_stack->inquiry_mode = inquiry_mode;
6543 }
6544 
6545 /**
6546  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6547  */
6548 void hci_set_sco_voice_setting(uint16_t voice_setting){
6549     hci_stack->sco_voice_setting = voice_setting;
6550 }
6551 
6552 /**
6553  * @brief Get SCO Voice Setting
6554  * @return current voice setting
6555  */
6556 uint16_t hci_get_sco_voice_setting(void){
6557     return hci_stack->sco_voice_setting;
6558 }
6559 
6560 static int hci_have_usb_transport(void){
6561     if (!hci_stack->hci_transport) return 0;
6562     const char * transport_name = hci_stack->hci_transport->name;
6563     if (!transport_name) return 0;
6564     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6565 }
6566 
6567 /** @brief Get SCO packet length for current SCO Voice setting
6568  *  @note  Using SCO packets of the exact length is required for USB transfer
6569  *  @return Length of SCO packets in bytes (not audio frames)
6570  */
6571 uint16_t hci_get_sco_packet_length(void){
6572     uint16_t sco_packet_length = 0;
6573 
6574 #ifdef ENABLE_SCO_OVER_HCI
6575     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6576     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6577 
6578     if (hci_have_usb_transport()){
6579         // see Core Spec for H2 USB Transfer.
6580         // 3 byte SCO header + 24 bytes per connection
6581         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6582         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6583     } else {
6584         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6585         sco_packet_length = 3 + 60 * multiplier;
6586         // assert that it still fits inside an SCO buffer
6587         if (sco_packet_length > hci_stack->sco_data_packet_length){
6588             sco_packet_length = 3 + 60;
6589         }
6590     }
6591 #endif
6592 
6593 #ifdef HAVE_SCO_TRANSPORT
6594     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6595     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6596     sco_packet_length = 3 + 60 * multiplier;
6597 #endif
6598     return sco_packet_length;
6599 }
6600 
6601 /**
6602 * @brief Sets the master/slave policy
6603 * @param policy (0: attempt to become master, 1: let connecting device decide)
6604 */
6605 void hci_set_master_slave_policy(uint8_t policy){
6606     hci_stack->master_slave_policy = policy;
6607 }
6608 
6609 #endif
6610 
6611 HCI_STATE hci_get_state(void){
6612     return hci_stack->state;
6613 }
6614 
6615 #ifdef ENABLE_CLASSIC
6616 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6617     hci_stack->gap_classic_accept_callback = accept_callback;
6618 }
6619 #endif
6620 
6621 /**
6622  * @brief Set callback for Bluetooth Hardware Error
6623  */
6624 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6625     hci_stack->hardware_error_callback = fn;
6626 }
6627 
6628 void hci_disconnect_all(void){
6629     btstack_linked_list_iterator_t it;
6630     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6631     while (btstack_linked_list_iterator_has_next(&it)){
6632         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6633         if (con->state == SENT_DISCONNECT) continue;
6634         con->state = SEND_DISCONNECT;
6635     }
6636     hci_run();
6637 }
6638 
6639 uint16_t hci_get_manufacturer(void){
6640     return hci_stack->manufacturer;
6641 }
6642 
6643 #ifdef ENABLE_BLE
6644 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6645     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6646     if (!hci_con) return NULL;
6647     return &hci_con->sm_connection;
6648 }
6649 
6650 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6651 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6652 #endif
6653 
6654 int gap_encryption_key_size(hci_con_handle_t con_handle){
6655     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6656     if (hci_connection == NULL) return 0;
6657     if (hci_is_le_connection(hci_connection)){
6658 #ifdef ENABLE_BLE
6659         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6660         if (sm_conn->sm_connection_encrypted) {
6661             return sm_conn->sm_actual_encryption_key_size;
6662         }
6663 #endif
6664     } else {
6665 #ifdef ENABLE_CLASSIC
6666         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6667             return hci_connection->encryption_key_size;
6668         }
6669 #endif
6670     }
6671     return 0;
6672 }
6673 
6674 int gap_authenticated(hci_con_handle_t con_handle){
6675     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6676     if (hci_connection == NULL) return 0;
6677 
6678     switch (hci_connection->address_type){
6679 #ifdef ENABLE_BLE
6680         case BD_ADDR_TYPE_LE_PUBLIC:
6681         case BD_ADDR_TYPE_LE_RANDOM:
6682             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6683             return hci_connection->sm_connection.sm_connection_authenticated;
6684 #endif
6685 #ifdef ENABLE_CLASSIC
6686         case BD_ADDR_TYPE_SCO:
6687         case BD_ADDR_TYPE_ACL:
6688             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6689 #endif
6690         default:
6691             return 0;
6692     }
6693 }
6694 
6695 int gap_secure_connection(hci_con_handle_t con_handle){
6696     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6697     if (hci_connection == NULL) return 0;
6698 
6699     switch (hci_connection->address_type){
6700 #ifdef ENABLE_BLE
6701         case BD_ADDR_TYPE_LE_PUBLIC:
6702         case BD_ADDR_TYPE_LE_RANDOM:
6703             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6704             return hci_connection->sm_connection.sm_connection_sc;
6705 #endif
6706 #ifdef ENABLE_CLASSIC
6707         case BD_ADDR_TYPE_SCO:
6708         case BD_ADDR_TYPE_ACL:
6709             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6710 #endif
6711         default:
6712             return 0;
6713     }
6714 }
6715 
6716 bool gap_bonded(hci_con_handle_t con_handle){
6717 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6718 	if (hci_connection == NULL) return 0;
6719 
6720 #ifdef ENABLE_CLASSIC
6721 	link_key_t link_key;
6722 	link_key_type_t link_key_type;
6723 #endif
6724 	switch (hci_connection->address_type){
6725 #ifdef ENABLE_BLE
6726 		case BD_ADDR_TYPE_LE_PUBLIC:
6727 		case BD_ADDR_TYPE_LE_RANDOM:
6728 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6729 #endif
6730 #ifdef ENABLE_CLASSIC
6731 		case BD_ADDR_TYPE_SCO:
6732 		case BD_ADDR_TYPE_ACL:
6733 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6734 #endif
6735 		default:
6736 			return false;
6737 	}
6738 }
6739 
6740 #ifdef ENABLE_BLE
6741 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6742     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6743     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6744     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6745     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6746     return sm_conn->sm_connection_authorization_state;
6747 }
6748 #endif
6749 
6750 #ifdef ENABLE_CLASSIC
6751 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){
6752     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6753     if (!conn) return GAP_CONNECTION_INVALID;
6754     conn->sniff_min_interval = sniff_min_interval;
6755     conn->sniff_max_interval = sniff_max_interval;
6756     conn->sniff_attempt = sniff_attempt;
6757     conn->sniff_timeout = sniff_timeout;
6758     hci_run();
6759     return 0;
6760 }
6761 
6762 /**
6763  * @brief Exit Sniff mode
6764  * @param con_handle
6765  @ @return 0 if ok
6766  */
6767 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6768     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6769     if (!conn) return GAP_CONNECTION_INVALID;
6770     conn->sniff_min_interval = 0xffff;
6771     hci_run();
6772     return 0;
6773 }
6774 
6775 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){
6776     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6777     if (!conn) return GAP_CONNECTION_INVALID;
6778     conn->sniff_subrating_max_latency = max_latency;
6779     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6780     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6781     hci_run();
6782     return ERROR_CODE_SUCCESS;
6783 }
6784 
6785 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){
6786     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6787     if (!conn) return GAP_CONNECTION_INVALID;
6788     conn->qos_service_type = service_type;
6789     conn->qos_token_rate = token_rate;
6790     conn->qos_peak_bandwidth = peak_bandwidth;
6791     conn->qos_latency = latency;
6792     conn->qos_delay_variation = delay_variation;
6793     hci_run();
6794     return ERROR_CODE_SUCCESS;
6795 }
6796 
6797 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6798     hci_stack->new_page_scan_interval = page_scan_interval;
6799     hci_stack->new_page_scan_window = page_scan_window;
6800     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6801     hci_run();
6802 }
6803 
6804 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6805     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6806     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6807     hci_run();
6808 }
6809 
6810 #endif
6811 
6812 void hci_halting_defer(void){
6813     if (hci_stack->state != HCI_STATE_HALTING) return;
6814     switch (hci_stack->substate){
6815         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6816         case HCI_HALTING_CLOSE:
6817             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6818             break;
6819         default:
6820             break;
6821     }
6822 }
6823 
6824 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6825 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6826     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6827     if (le_device_db_index >= le_device_db_max_count()) return;
6828     uint8_t offset = le_device_db_index >> 3;
6829     uint8_t mask = 1 << (le_device_db_index & 7);
6830     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6831     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6832     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6833         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6834     }
6835 }
6836 
6837 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6838 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6839 	if (le_device_db_index >= le_device_db_max_count()) return;
6840 	uint8_t offset = le_device_db_index >> 3;
6841 	uint8_t mask = 1 << (le_device_db_index & 7);
6842 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6843 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6844 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6845 	}
6846 }
6847 
6848 uint8_t gap_load_resolving_list_from_le_device_db(void){
6849 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6850 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6851 	}
6852 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6853 		// restart le resolving list update
6854 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6855 	}
6856 	return ERROR_CODE_SUCCESS;
6857 }
6858 #endif
6859 
6860 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6861 void hci_setup_test_connections_fuzz(void){
6862     hci_connection_t * conn;
6863 
6864     // default address: 66:55:44:33:00:01
6865     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6866 
6867     // setup Controller info
6868     hci_stack->num_cmd_packets = 255;
6869     hci_stack->acl_packets_total_num = 255;
6870 
6871     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6872     addr[5] = 0x01;
6873     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6874     conn->con_handle = addr[5];
6875     conn->role  = HCI_ROLE_SLAVE;
6876     conn->state = RECEIVED_CONNECTION_REQUEST;
6877     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6878 
6879     // setup incoming Classic SCO connection with con handle 0x0002
6880     addr[5] = 0x02;
6881     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6882     conn->con_handle = addr[5];
6883     conn->role  = HCI_ROLE_SLAVE;
6884     conn->state = RECEIVED_CONNECTION_REQUEST;
6885     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6886 
6887     // setup ready Classic ACL connection with con handle 0x0003
6888     addr[5] = 0x03;
6889     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6890     conn->con_handle = addr[5];
6891     conn->role  = HCI_ROLE_SLAVE;
6892     conn->state = OPEN;
6893     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6894 
6895     // setup ready Classic SCO connection with con handle 0x0004
6896     addr[5] = 0x04;
6897     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6898     conn->con_handle = addr[5];
6899     conn->role  = HCI_ROLE_SLAVE;
6900     conn->state = OPEN;
6901     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6902 
6903     // setup ready LE ACL connection with con handle 0x005 and public address
6904     addr[5] = 0x05;
6905     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6906     conn->con_handle = addr[5];
6907     conn->role  = HCI_ROLE_SLAVE;
6908     conn->state = OPEN;
6909     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6910     conn->sm_connection.sm_connection_encrypted = 1;
6911 }
6912 
6913 void hci_free_connections_fuzz(void){
6914     btstack_linked_list_iterator_t it;
6915     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6916     while (btstack_linked_list_iterator_has_next(&it)){
6917         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6918         btstack_linked_list_iterator_remove(&it);
6919         btstack_memory_hci_connection_free(con);
6920     }
6921 }
6922 void hci_simulate_working_fuzz(void){
6923     hci_init_done();
6924     hci_stack->num_cmd_packets = 255;
6925 }
6926 #endif
6927