xref: /btstack/src/hci.c (revision 699a5fcacbfd53f83fef80a3dbe48022b4831d05)
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()){
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()){
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 #ifdef ENABLE_BLE
2012 
2013 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2014         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
2015             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
2016             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
2017                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
2018                 return;
2019             }
2020             // explicit fall through to reduce repetitions
2021 
2022 #ifdef ENABLE_LE_CENTRAL
2023             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
2024 #else
2025             hci_stack->substate = HCI_INIT_DONE;
2026 #endif
2027             return;
2028 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
2029 
2030 #endif  /* ENABLE_BLE */
2031 
2032         case HCI_INIT_DONE:
2033             // set state if we came here by fall through
2034             hci_stack->substate = HCI_INIT_DONE;
2035             return;
2036 
2037         default:
2038             break;
2039     }
2040     hci_initializing_next_state();
2041 }
2042 
2043 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2044     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2045     bd_addr_t bd_address;
2046     (void)memcpy(&bd_address, conn->address, 6);
2047 
2048 #ifdef ENABLE_CLASSIC
2049     // cache needed data
2050     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2051 #endif
2052 
2053     // connection failed, remove entry
2054     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2055     btstack_memory_hci_connection_free( conn );
2056 
2057 #ifdef ENABLE_CLASSIC
2058     // notify client if dedicated bonding
2059     if (notify_dedicated_bonding_failed){
2060         log_info("hci notify_dedicated_bonding_failed");
2061         hci_emit_dedicated_bonding_result(bd_address, status);
2062     }
2063 
2064     // if authentication error, also delete link key
2065     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2066         gap_drop_link_key_for_bd_addr(bd_address);
2067     }
2068 #else
2069     UNUSED(status);
2070 #endif
2071 }
2072 
2073 #ifdef ENABLE_CLASSIC
2074 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2075     // SSP Controller
2076     if (features[6] & (1 << 3)){
2077         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2078     }
2079     // eSCO
2080     if (features[3] & (1<<7)){
2081         conn->remote_supported_features[0] |= 1;
2082     }
2083     // Extended features
2084     if (features[7] & (1<<7)){
2085         conn->remote_supported_features[0] |= 2;
2086     }
2087 }
2088 
2089 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2090     // SSP Host
2091     if (features[0] & (1 << 0)){
2092         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2093     }
2094     // SC Host
2095     if (features[0] & (1 << 3)){
2096         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2097     }
2098 }
2099 
2100 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2101     // SC Controller
2102     if (features[1] & (1 << 0)){
2103         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2104     }
2105 }
2106 
2107 static void hci_handle_remote_features_received(hci_connection_t * conn){
2108     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2109     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2110     if (conn->bonding_flags & BONDING_DEDICATED){
2111         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2112     }
2113 }
2114 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2115     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2116     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2117 }
2118 
2119 #endif
2120 
2121 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2122     // handle BT initialization
2123     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2124         hci_initializing_event_handler(packet, size);
2125     }
2126 
2127     // help with BT sleep
2128     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2129         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2130         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2131         hci_initializing_next_state();
2132     }
2133 }
2134 
2135 #ifdef ENABLE_CLASSIC
2136 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2137     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2138     conn->encryption_key_size = encryption_key_size;
2139 
2140     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2141         conn->requested_security_level = LEVEL_0;
2142         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2143         return;
2144     }
2145 
2146     // Request Authentication if not already done
2147     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2148     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2149 }
2150 #endif
2151 
2152 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2153     UNUSED(size);
2154 
2155     uint16_t manufacturer;
2156 #ifdef ENABLE_CLASSIC
2157     hci_con_handle_t handle;
2158     hci_connection_t * conn;
2159     uint8_t status;
2160 #endif
2161     // get num cmd packets - limit to 1 to reduce complexity
2162     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2163 
2164     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2165     switch (opcode){
2166         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2167             if (packet[5]) break;
2168             // terminate, name 248 chars
2169             packet[6+248] = 0;
2170             log_info("local name: %s", &packet[6]);
2171             break;
2172         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2173             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2174             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2175                 uint16_t acl_len = little_endian_read_16(packet, 6);
2176                 uint16_t sco_len = packet[8];
2177 
2178                 // determine usable ACL/SCO payload size
2179                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2180                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2181 
2182                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2183                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2184 
2185                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2186                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2187                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2188             }
2189             break;
2190         case HCI_OPCODE_HCI_READ_RSSI:
2191             if (packet[5] == ERROR_CODE_SUCCESS){
2192                 uint8_t event[5];
2193                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2194                 event[1] = 3;
2195                 (void)memcpy(&event[2], &packet[6], 3);
2196                 hci_emit_event(event, sizeof(event), 1);
2197             }
2198             break;
2199 #ifdef ENABLE_BLE
2200         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2201             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2202             hci_stack->le_acl_packets_total_num = packet[8];
2203             // determine usable ACL payload size
2204             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2205                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2206             }
2207             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2208             break;
2209 #endif
2210 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2211         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2212             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2213             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2214             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);
2215             break;
2216 #endif
2217 #ifdef ENABLE_LE_CENTRAL
2218         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2219             hci_stack->le_whitelist_capacity = packet[6];
2220             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2221             break;
2222 #endif
2223         case HCI_OPCODE_HCI_READ_BD_ADDR:
2224             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2225             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));
2226 #ifdef ENABLE_CLASSIC
2227             if (hci_stack->link_key_db){
2228                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2229             }
2230 #endif
2231             break;
2232 #ifdef ENABLE_CLASSIC
2233         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2234             hci_emit_discoverable_enabled(hci_stack->discoverable);
2235             break;
2236         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2237             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2238                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2239                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2240                 hci_emit_event(event, sizeof(event), 1);
2241             }
2242             break;
2243 #endif
2244         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2245             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2246 
2247 #ifdef ENABLE_CLASSIC
2248             // determine usable ACL packet types based on host buffer size and supported features
2249             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2250             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2251 #endif
2252             // Classic/LE
2253             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2254             break;
2255         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2256             manufacturer = little_endian_read_16(packet, 10);
2257             // map Cypress to Broadcom
2258             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2259                 log_info("Treat Cypress as Broadcom");
2260                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2261                 little_endian_store_16(packet, 10, manufacturer);
2262             }
2263             hci_stack->manufacturer = manufacturer;
2264             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2265             break;
2266         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2267             hci_stack->local_supported_commands[0] =
2268                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2269                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2270                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2271                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2272                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2273                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2274                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2275                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2276             hci_stack->local_supported_commands[1] =
2277                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2278                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2279                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2280                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2281                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2282             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2283             break;
2284 #ifdef ENABLE_CLASSIC
2285         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2286             if (packet[5]) return;
2287             hci_stack->synchronous_flow_control_enabled = 1;
2288             break;
2289         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2290             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2291             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2292             conn   = hci_connection_for_handle(handle);
2293             if (conn != NULL) {
2294                 uint8_t key_size = 0;
2295                 if (status == 0){
2296                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2297                     log_info("Handle %04x key Size: %u", handle, key_size);
2298                 } else {
2299                     key_size = 1;
2300                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2301                 }
2302                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2303             }
2304             break;
2305         // assert pairing complete event is emitted.
2306         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2307         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2308         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2309         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2310             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2311             // lookup connection by gap pairing addr
2312             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2313             if (conn == NULL) break;
2314             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2315             break;
2316 
2317 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2318         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2319         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2320             uint8_t event[67];
2321             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2322             event[1] = 65;
2323             (void)memset(&event[2], 0, 65);
2324             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2325                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2326                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2327                     event[2] = 3;
2328                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2329                 } else {
2330                     event[2] = 1;
2331                 }
2332             }
2333             hci_emit_event(event, sizeof(event), 0);
2334             break;
2335         }
2336 
2337         // note: only needed if user does not provide OOB data
2338         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2339             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2340             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2341             if (conn == NULL) break;
2342             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2343             break;
2344 #endif
2345 #endif
2346         default:
2347             break;
2348     }
2349 }
2350 
2351 #ifdef ENABLE_BLE
2352 static void event_handle_le_connection_complete(const uint8_t * packet){
2353 	bd_addr_t addr;
2354 	bd_addr_type_t addr_type;
2355 	hci_connection_t * conn;
2356 
2357 	// Connection management
2358 	reverse_bd_addr(&packet[8], addr);
2359 	addr_type = (bd_addr_type_t)packet[7];
2360 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2361 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2362 
2363 #ifdef ENABLE_LE_CENTRAL
2364 	// handle error: error is reported only to the initiator -> outgoing connection
2365 	if (packet[3]){
2366 
2367 		// handle cancelled outgoing connection
2368 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2369 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2370 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2371 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2372 		    // reset state
2373             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2374             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2375 			// get outgoing connection conn struct for direct connect
2376 			conn = gap_get_outgoing_connection();
2377 		}
2378 
2379 		// outgoing le connection establishment is done
2380 		if (conn){
2381 			// remove entry
2382 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2383 			btstack_memory_hci_connection_free( conn );
2384 		}
2385 		return;
2386 	}
2387 #endif
2388 
2389 	// on success, both hosts receive connection complete event
2390 	if (packet[6] == HCI_ROLE_MASTER){
2391 #ifdef ENABLE_LE_CENTRAL
2392 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2393 		// note: no hci_connection_t object exists yet for connect with whitelist
2394 		if (hci_is_le_connection_type(addr_type)){
2395 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2396 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2397 		}
2398 #endif
2399 	} else {
2400 #ifdef ENABLE_LE_PERIPHERAL
2401 		// if we're slave, it was an incoming connection, advertisements have stopped
2402 		hci_stack->le_advertisements_active = false;
2403 #endif
2404 	}
2405 
2406 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2407 	if (!conn){
2408 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2409 	}
2410 
2411 	// no memory, sorry.
2412 	if (!conn){
2413 		return;
2414 	}
2415 
2416 	conn->state = OPEN;
2417 	conn->role  = packet[6];
2418 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2419 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2420 
2421 #ifdef ENABLE_LE_PERIPHERAL
2422 	if (packet[6] == HCI_ROLE_SLAVE){
2423 		hci_update_advertisements_enabled_for_current_roles();
2424 	}
2425 #endif
2426 
2427     // init unenhanced att bearer mtu
2428     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2429     conn->att_connection.mtu_exchanged = false;
2430 
2431     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2432 
2433 	// restart timer
2434 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2435 	// btstack_run_loop_add_timer(&conn->timeout);
2436 
2437 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2438 
2439 	hci_emit_nr_connections_changed();
2440 }
2441 #endif
2442 
2443 #ifdef ENABLE_CLASSIC
2444 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){
2445     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2446     // LEVEL_4 is tested by l2cap
2447     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2448     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2449     if (level >= LEVEL_3){
2450         // MITM not possible without keyboard or display
2451         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2452         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2453 
2454         // MITM possible if one side has keyboard and the other has keyboard or display
2455         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2456         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2457 
2458         // MITM not possible if one side has only display and other side has no keyboard
2459         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2460         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2461     }
2462     // LEVEL 2 requires SSP, which is a given
2463     return true;
2464 }
2465 
2466 static bool btstack_is_null(uint8_t * data, uint16_t size){
2467     uint16_t i;
2468     for (i=0; i < size ; i++){
2469         if (data[i] != 0) {
2470             return false;
2471         }
2472     }
2473     return true;
2474 }
2475 
2476 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2477     // get requested security level
2478     gap_security_level_t requested_security_level = conn->requested_security_level;
2479     if (hci_stack->gap_secure_connections_only_mode){
2480         requested_security_level = LEVEL_4;
2481     }
2482 
2483     // assess security: LEVEL 4 requires SC
2484     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2485     if ((requested_security_level == LEVEL_4) &&
2486         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2487         !hci_remote_sc_enabled(conn)){
2488         log_info("Level 4 required, but SC not supported -> abort");
2489         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2490         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2491         return;
2492     }
2493 
2494     // assess security based on io capabilities
2495     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2496         // responder: fully validate io caps of both sides as well as OOB data
2497         bool security_possible = false;
2498         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2499 
2500 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2501         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2502         // so we merge the OOB data availability
2503         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2504         if (conn->classic_oob_c_192 != NULL){
2505             have_oob_data |= 1;
2506         }
2507         if (conn->classic_oob_c_256 != NULL){
2508             have_oob_data |= 2;
2509         }
2510         // for up to Level 3, either P-192 as well as P-256 will do
2511         // 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
2512         // if remote does not SC, we should not receive P-256 data either
2513         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2514             security_possible = true;
2515         }
2516         // for Level 4, P-256 is needed
2517         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2518             security_possible = true;
2519         }
2520 #endif
2521 
2522         if (security_possible == false){
2523             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2524             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2525             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2526             return;
2527         }
2528     } else {
2529         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2530 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2531 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2532         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2533             log_info("Level 3+ required, but no input/output -> abort");
2534             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2535             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2536             return;
2537         }
2538 #endif
2539 #endif
2540     }
2541 
2542 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2543     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2544         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2545     } else {
2546         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2547     }
2548 #endif
2549 }
2550 
2551 #endif
2552 
2553 static void event_handler(uint8_t *packet, uint16_t size){
2554 
2555     uint16_t event_length = packet[1];
2556 
2557     // assert packet is complete
2558     if (size != (event_length + 2u)){
2559         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2560         return;
2561     }
2562 
2563     bd_addr_type_t addr_type;
2564     hci_con_handle_t handle;
2565     hci_connection_t * conn;
2566     int i;
2567     int create_connection_cmd;
2568 
2569 #ifdef ENABLE_CLASSIC
2570     hci_link_type_t link_type;
2571     bd_addr_t addr;
2572 #endif
2573 
2574     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2575 
2576     switch (hci_event_packet_get_type(packet)) {
2577 
2578         case HCI_EVENT_COMMAND_COMPLETE:
2579             handle_command_complete_event(packet, size);
2580             break;
2581 
2582         case HCI_EVENT_COMMAND_STATUS:
2583             // get num cmd packets - limit to 1 to reduce complexity
2584             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2585 
2586             // check command status to detected failed outgoing connections
2587             create_connection_cmd = 0;
2588 #ifdef ENABLE_CLASSIC
2589             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2590                 create_connection_cmd = 1;
2591             }
2592 #endif
2593 #ifdef ENABLE_LE_CENTRAL
2594             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2595                 create_connection_cmd = 1;
2596             }
2597 #endif
2598             if (create_connection_cmd) {
2599                 uint8_t status = hci_event_command_status_get_status(packet);
2600                 addr_type = hci_stack->outgoing_addr_type;
2601                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2602                 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);
2603 
2604                 // reset outgoing address info
2605                 memset(hci_stack->outgoing_addr, 0, 6);
2606                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2607 
2608                 // on error
2609                 if (status != ERROR_CODE_SUCCESS){
2610 #ifdef ENABLE_LE_CENTRAL
2611                     if (hci_is_le_connection_type(addr_type)){
2612                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2613                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2614                     }
2615 #endif
2616                     // error => outgoing connection failed
2617                     if (conn != NULL){
2618                         hci_handle_connection_failed(conn, status);
2619                     }
2620                 }
2621             }
2622 
2623 #ifdef ENABLE_CLASSIC
2624             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2625                 uint8_t status = hci_event_command_status_get_status(packet);
2626                 log_info("command status (inquiry), status %x", status);
2627                 if (status == ERROR_CODE_SUCCESS) {
2628                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2629                 } else {
2630                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2631                 }
2632             }
2633 #endif
2634             break;
2635 
2636         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2637             if (size < 3) return;
2638             uint16_t num_handles = packet[2];
2639             if (size != (3u + num_handles * 4u)) return;
2640             uint16_t offset = 3;
2641             for (i=0; i<num_handles;i++){
2642                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2643                 offset += 2u;
2644                 uint16_t num_packets = little_endian_read_16(packet, offset);
2645                 offset += 2u;
2646 
2647                 conn = hci_connection_for_handle(handle);
2648                 if (!conn){
2649                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2650                     continue;
2651                 }
2652 
2653                 if (conn->num_packets_sent >= num_packets){
2654                     conn->num_packets_sent -= num_packets;
2655                 } else {
2656                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2657                     conn->num_packets_sent = 0;
2658                 }
2659                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2660 
2661 #ifdef ENABLE_CLASSIC
2662                 // For SCO, we do the can_send_now_check here
2663                 hci_notify_if_sco_can_send_now();
2664 #endif
2665             }
2666             break;
2667         }
2668 
2669 #ifdef ENABLE_CLASSIC
2670         case HCI_EVENT_INQUIRY_COMPLETE:
2671             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2672                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2673                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2674                 hci_emit_event(event, sizeof(event), 1);
2675             }
2676             break;
2677         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2678             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2679                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2680             }
2681             break;
2682         case HCI_EVENT_CONNECTION_REQUEST:
2683             reverse_bd_addr(&packet[2], addr);
2684             link_type = (hci_link_type_t) packet[11];
2685 
2686             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2687             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2688                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2689                 bd_addr_copy(hci_stack->decline_addr, addr);
2690                 break;
2691             }
2692 
2693             if (hci_stack->gap_classic_accept_callback != NULL){
2694                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2695                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2696                     bd_addr_copy(hci_stack->decline_addr, addr);
2697                     break;
2698                 }
2699             }
2700 
2701             // TODO: eval COD 8-10
2702             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2703             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2704             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2705             if (!conn) {
2706                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2707             }
2708             if (!conn) {
2709                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2710                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2711                 bd_addr_copy(hci_stack->decline_addr, addr);
2712                 break;
2713             }
2714             conn->role  = HCI_ROLE_SLAVE;
2715             conn->state = RECEIVED_CONNECTION_REQUEST;
2716             // store info about eSCO
2717             if (link_type == HCI_LINK_TYPE_ESCO){
2718                 conn->remote_supported_features[0] |= 1;
2719             }
2720             hci_run();
2721             break;
2722 
2723         case HCI_EVENT_CONNECTION_COMPLETE:
2724             // Connection management
2725             reverse_bd_addr(&packet[5], addr);
2726             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2727             addr_type = BD_ADDR_TYPE_ACL;
2728             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2729             if (conn) {
2730                 if (!packet[2]){
2731                     conn->state = OPEN;
2732                     conn->con_handle = little_endian_read_16(packet, 3);
2733 
2734                     // queue get remote feature
2735                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2736 
2737                     // queue set supervision timeout if we're master
2738                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2739                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2740                     }
2741 
2742                     // restart timer
2743                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2744                     btstack_run_loop_add_timer(&conn->timeout);
2745 
2746                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2747 
2748                     hci_emit_nr_connections_changed();
2749                 } else {
2750                     // connection failed
2751                     hci_handle_connection_failed(conn, packet[2]);
2752                 }
2753             }
2754             break;
2755 
2756         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2757             reverse_bd_addr(&packet[5], addr);
2758             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2759             if (packet[2]){
2760                 // connection failed
2761                 break;
2762             }
2763             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2764             if (!conn) {
2765                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2766             }
2767             if (!conn) {
2768                 break;
2769             }
2770             conn->state = OPEN;
2771             conn->con_handle = little_endian_read_16(packet, 3);
2772 
2773 #ifdef ENABLE_SCO_OVER_HCI
2774             // update SCO
2775             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2776                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2777             }
2778             // trigger can send now
2779             if (hci_have_usb_transport()){
2780                 hci_stack->sco_can_send_now = true;
2781             }
2782 #endif
2783 #ifdef HAVE_SCO_TRANSPORT
2784             // configure sco transport
2785             if (hci_stack->sco_transport != NULL){
2786                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2787                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2788             }
2789 #endif
2790             break;
2791 
2792         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2793             handle = little_endian_read_16(packet, 3);
2794             conn = hci_connection_for_handle(handle);
2795             if (!conn) break;
2796             if (!packet[2]){
2797                 const uint8_t * features = &packet[5];
2798                 hci_handle_remote_features_page_0(conn, features);
2799 
2800                 // read extended features if possible
2801                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2802                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2803                     break;
2804                 }
2805             }
2806             hci_handle_remote_features_received(conn);
2807             break;
2808 
2809         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2810             handle = little_endian_read_16(packet, 3);
2811             conn = hci_connection_for_handle(handle);
2812             if (!conn) break;
2813             // status = ok, page = 1
2814             if (!packet[2]) {
2815                 uint8_t page_number = packet[5];
2816                 uint8_t maximum_page_number = packet[6];
2817                 const uint8_t * features = &packet[7];
2818                 bool done = false;
2819                 switch (page_number){
2820                     case 1:
2821                         hci_handle_remote_features_page_1(conn, features);
2822                         if (maximum_page_number >= 2){
2823                             // get Secure Connections (Controller) from Page 2 if available
2824                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2825                         } else {
2826                             // otherwise, assume SC (Controller) == SC (Host)
2827                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2828                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2829                             }
2830                             done = true;
2831                         }
2832                         break;
2833                     case 2:
2834                         hci_handle_remote_features_page_2(conn, features);
2835                         done = true;
2836                         break;
2837                     default:
2838                         break;
2839                 }
2840                 if (!done) break;
2841             }
2842             hci_handle_remote_features_received(conn);
2843             break;
2844 
2845         case HCI_EVENT_LINK_KEY_REQUEST:
2846 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2847             hci_event_link_key_request_get_bd_addr(packet, addr);
2848             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2849             if (!conn) break;
2850 
2851             // lookup link key in db if not cached
2852             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2853                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2854             }
2855 
2856             // response sent by hci_run()
2857             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2858 #endif
2859             break;
2860 
2861         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2862             hci_event_link_key_request_get_bd_addr(packet, addr);
2863             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2864             if (!conn) break;
2865 
2866             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2867 
2868             // CVE-2020-26555: ignore NULL link key
2869             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2870             if (btstack_is_null(&packet[8], 16)) break;
2871 
2872             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2873             // Change Connection Encryption keeps link key type
2874             if (link_key_type != CHANGED_COMBINATION_KEY){
2875                 conn->link_key_type = link_key_type;
2876             }
2877 
2878             // cache link key. link keys stored in little-endian format for legacy reasons
2879             memcpy(&conn->link_key, &packet[8], 16);
2880 
2881             // only store link key:
2882             // - if bondable enabled
2883             if (hci_stack->bondable == false) break;
2884             // - if security level sufficient
2885             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2886             // - for SSP, also check if remote side requested bonding as well
2887             if (conn->link_key_type != COMBINATION_KEY){
2888                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2889                 if (!remote_bonding){
2890                     break;
2891                 }
2892             }
2893             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2894             break;
2895         }
2896 
2897         case HCI_EVENT_PIN_CODE_REQUEST:
2898             hci_event_pin_code_request_get_bd_addr(packet, addr);
2899             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2900             if (!conn) break;
2901 
2902             hci_pairing_started(conn, false);
2903             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2904             if (!hci_stack->bondable ){
2905                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2906                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2907                 hci_run();
2908                 return;
2909             }
2910             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2911             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2912                 log_info("Level 4 required, but SC not supported -> abort");
2913                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2914                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2915                 hci_run();
2916                 return;
2917             }
2918             break;
2919 
2920         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2921             hci_event_io_capability_response_get_bd_addr(packet, addr);
2922             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2923             if (!conn) break;
2924 
2925             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2926             hci_pairing_started(conn, true);
2927             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2928             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2929 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2930             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2931 #endif
2932             break;
2933 
2934         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2935             hci_event_io_capability_response_get_bd_addr(packet, addr);
2936             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2937             if (!conn) break;
2938 
2939             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2940             hci_connection_timestamp(conn);
2941             hci_pairing_started(conn, true);
2942             break;
2943 
2944 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2945         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2946             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2947             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2948             if (!conn) break;
2949 
2950             hci_connection_timestamp(conn);
2951 
2952             hci_pairing_started(conn, true);
2953 
2954             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2955             break;
2956 #endif
2957 
2958         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2959             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2960             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2961             if (!conn) break;
2962             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2963                 if (hci_stack->ssp_auto_accept){
2964                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2965                 };
2966             } else {
2967                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2968                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2969                 // don't forward event to app
2970                 hci_run();
2971                 return;
2972             }
2973             break;
2974 
2975         case HCI_EVENT_USER_PASSKEY_REQUEST:
2976             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2977             if (hci_stack->ssp_auto_accept){
2978                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2979             };
2980             break;
2981 
2982         case HCI_EVENT_MODE_CHANGE:
2983             handle = hci_event_mode_change_get_handle(packet);
2984             conn = hci_connection_for_handle(handle);
2985             if (!conn) break;
2986             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2987             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2988             break;
2989 #endif
2990 
2991         case HCI_EVENT_ENCRYPTION_CHANGE:
2992             handle = hci_event_encryption_change_get_connection_handle(packet);
2993             conn = hci_connection_for_handle(handle);
2994             if (!conn) break;
2995             if (hci_event_encryption_change_get_status(packet) == 0u) {
2996                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2997                 if (encryption_enabled){
2998                     if (hci_is_le_connection(conn)){
2999                         // For LE, we accept connection as encrypted
3000                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
3001                     }
3002 #ifdef ENABLE_CLASSIC
3003                     else {
3004 
3005                         // dedicated bonding: send result and disconnect
3006                         if (conn->bonding_flags & BONDING_DEDICATED){
3007                             conn->bonding_flags &= ~BONDING_DEDICATED;
3008                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
3009                             conn->bonding_status = packet[2];
3010                             break;
3011                         }
3012 
3013                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
3014                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
3015                         bool connected_uses_aes_ccm = encryption_enabled == 2;
3016                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
3017                             log_info("SC during pairing, but only E0 now -> abort");
3018                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
3019                             break;
3020                         }
3021 
3022                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
3023                         if (connected_uses_aes_ccm){
3024                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3025                         }
3026 
3027 #ifdef ENABLE_TESTING_SUPPORT
3028                         // work around for issue with PTS dongle
3029                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3030 #endif
3031 
3032                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3033                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3034                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3035                         } else {
3036                             // if not, pretend everything is perfect
3037                             hci_handle_read_encryption_key_size_complete(conn, 16);
3038                         }
3039                     }
3040 #endif
3041                 } else {
3042                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3043                 }
3044             }
3045 
3046             break;
3047 
3048 #ifdef ENABLE_CLASSIC
3049         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3050             handle = hci_event_authentication_complete_get_connection_handle(packet);
3051             conn = hci_connection_for_handle(handle);
3052             if (!conn) break;
3053 
3054             // clear authentication active flag
3055             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3056             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3057 
3058             // authenticated only if auth status == 0
3059             if (hci_event_authentication_complete_get_status(packet) == 0){
3060                 // authenticated
3061                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3062 
3063                 // If not already encrypted, start encryption
3064                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3065                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3066                     break;
3067                 }
3068             }
3069 
3070             // emit updated security level
3071             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3072             break;
3073 
3074         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3075             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3076             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3077             if (!conn) break;
3078 
3079             // treat successfully paired connection as authenticated
3080             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3081                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3082             }
3083 
3084             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3085             break;
3086 #endif
3087 
3088         // HCI_EVENT_DISCONNECTION_COMPLETE
3089         // has been split, to first notify stack before shutting connection down
3090         // see end of function, too.
3091         case HCI_EVENT_DISCONNECTION_COMPLETE:
3092             if (packet[2]) break;   // status != 0
3093             handle = little_endian_read_16(packet, 3);
3094             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3095             if (hci_stack->acl_fragmentation_total_size > 0u) {
3096                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3097                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3098                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3099                     hci_stack->acl_fragmentation_total_size = 0;
3100                     hci_stack->acl_fragmentation_pos = 0;
3101                     if (release_buffer){
3102                         hci_release_packet_buffer();
3103                     }
3104                 }
3105             }
3106 
3107             conn = hci_connection_for_handle(handle);
3108             if (!conn) break;
3109 #ifdef ENABLE_CLASSIC
3110             // pairing failed if it was ongoing
3111             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3112 #endif
3113 
3114             // emit dedicatd bonding event
3115             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3116                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3117             }
3118 
3119             // mark connection for shutdown, stop timers, reset state
3120             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3121             hci_connection_stop_timer(conn);
3122             hci_connection_init(conn);
3123 
3124 #ifdef ENABLE_BLE
3125 #ifdef ENABLE_LE_PERIPHERAL
3126             // re-enable advertisements for le connections if active
3127             if (hci_is_le_connection(conn)){
3128                 hci_update_advertisements_enabled_for_current_roles();
3129             }
3130 #endif
3131 #endif
3132             break;
3133 
3134         case HCI_EVENT_HARDWARE_ERROR:
3135             log_error("Hardware Error: 0x%02x", packet[2]);
3136             if (hci_stack->hardware_error_callback){
3137                 (*hci_stack->hardware_error_callback)(packet[2]);
3138             } else {
3139                 // if no special requests, just reboot stack
3140                 hci_power_control_off();
3141                 hci_power_control_on();
3142             }
3143             break;
3144 
3145 #ifdef ENABLE_CLASSIC
3146         case HCI_EVENT_ROLE_CHANGE:
3147             if (packet[2]) break;   // status != 0
3148             reverse_bd_addr(&packet[3], addr);
3149             addr_type = BD_ADDR_TYPE_ACL;
3150             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3151             if (!conn) break;
3152             conn->role = packet[9];
3153             break;
3154 #endif
3155 
3156         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3157             // release packet buffer only for asynchronous transport and if there are not further fragements
3158             if (hci_transport_synchronous()) {
3159                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3160                 return; // instead of break: to avoid re-entering hci_run()
3161             }
3162             hci_stack->acl_fragmentation_tx_active = 0;
3163             if (hci_stack->acl_fragmentation_total_size) break;
3164             hci_release_packet_buffer();
3165 
3166             // L2CAP receives this event via the hci_emit_event below
3167 
3168 #ifdef ENABLE_CLASSIC
3169             // For SCO, we do the can_send_now_check here
3170             hci_notify_if_sco_can_send_now();
3171 #endif
3172             break;
3173 
3174 #ifdef ENABLE_CLASSIC
3175         case HCI_EVENT_SCO_CAN_SEND_NOW:
3176             // For SCO, we do the can_send_now_check here
3177             hci_stack->sco_can_send_now = true;
3178             hci_notify_if_sco_can_send_now();
3179             return;
3180 
3181         // explode inquriy results for easier consumption
3182         case HCI_EVENT_INQUIRY_RESULT:
3183         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3184         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3185             gap_inquiry_explode(packet, size);
3186             break;
3187 #endif
3188 
3189 #ifdef ENABLE_BLE
3190         case HCI_EVENT_LE_META:
3191             switch (packet[2]){
3192 #ifdef ENABLE_LE_CENTRAL
3193                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3194                     // log_info("advertising report received");
3195                     if (!hci_stack->le_scanning_enabled) break;
3196                     le_handle_advertisement_report(packet, size);
3197                     break;
3198 #endif
3199                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3200 					event_handle_le_connection_complete(packet);
3201                     break;
3202 
3203                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3204                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3205                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3206                     conn = hci_connection_for_handle(handle);
3207                     if (!conn) break;
3208                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3209                     break;
3210 
3211                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3212                     // connection
3213                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3214                     conn = hci_connection_for_handle(handle);
3215                     if (conn) {
3216                         // read arguments
3217                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3218                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3219                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3220                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3221 
3222                         // validate against current connection parameter range
3223                         le_connection_parameter_range_t existing_range;
3224                         gap_get_connection_parameter_range(&existing_range);
3225                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3226                         if (update_parameter){
3227                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3228                             conn->le_conn_interval_min = le_conn_interval_min;
3229                             conn->le_conn_interval_max = le_conn_interval_max;
3230                             conn->le_conn_latency = le_conn_latency;
3231                             conn->le_supervision_timeout = le_supervision_timeout;
3232                         } else {
3233                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3234                         }
3235                     }
3236                     break;
3237 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3238                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3239                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3240                     conn = hci_connection_for_handle(handle);
3241                     if (conn) {
3242                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3243                     }
3244                     break;
3245 #endif
3246                 default:
3247                     break;
3248             }
3249             break;
3250 #endif
3251         case HCI_EVENT_VENDOR_SPECIFIC:
3252             // Vendor specific commands often create vendor specific event instead of num completed packets
3253             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3254             switch (hci_stack->manufacturer){
3255                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3256                     hci_stack->num_cmd_packets = 1;
3257                     break;
3258                 default:
3259                     break;
3260             }
3261             break;
3262         default:
3263             break;
3264     }
3265 
3266     handle_event_for_current_stack_state(packet, size);
3267 
3268     // notify upper stack
3269 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3270 
3271     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3272     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3273 		handle = little_endian_read_16(packet, 3);
3274 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3275 		// discard connection if app did not trigger a reconnect in the event handler
3276 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3277 			hci_shutdown_connection(aConn);
3278 		}
3279     }
3280 
3281 	// execute main loop
3282 	hci_run();
3283 }
3284 
3285 #ifdef ENABLE_CLASSIC
3286 
3287 #ifdef ENABLE_SCO_OVER_HCI
3288 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3289 static void sco_schedule_tx(hci_connection_t * conn);
3290 
3291 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3292     log_debug("SCO TX Timeout");
3293     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3294     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3295     if (!conn) return;
3296 
3297     // trigger send
3298     conn->sco_tx_ready = 1;
3299     // extra packet if CVSD but SCO buffer is too short
3300     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3301         conn->sco_tx_ready++;
3302     }
3303     hci_notify_if_sco_can_send_now();
3304 }
3305 
3306 
3307 #define SCO_TX_AFTER_RX_MS (6)
3308 
3309 static void sco_schedule_tx(hci_connection_t * conn){
3310 
3311     uint32_t now = btstack_run_loop_get_time_ms();
3312     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3313     int time_delta_ms = sco_tx_ms - now;
3314 
3315     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3316 
3317     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3318     btstack_run_loop_remove_timer(timer);
3319     btstack_run_loop_set_timer(timer, time_delta_ms);
3320     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3321     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3322     btstack_run_loop_add_timer(timer);
3323 }
3324 #endif
3325 
3326 static void sco_handler(uint8_t * packet, uint16_t size){
3327     // lookup connection struct
3328     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3329     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3330     if (!conn) return;
3331 
3332 #ifdef ENABLE_SCO_OVER_HCI
3333     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3334     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3335         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3336             packet[2] = 0x3c;
3337             memmove(&packet[3], &packet[23], 63);
3338             size = 63;
3339         }
3340     }
3341 
3342     if (hci_have_usb_transport()){
3343         // Nothing to do
3344     } else {
3345         // 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);
3346         if (hci_stack->synchronous_flow_control_enabled == 0){
3347             uint32_t now = btstack_run_loop_get_time_ms();
3348 
3349             if (!conn->sco_rx_valid){
3350                 // ignore first 10 packets
3351                 conn->sco_rx_count++;
3352                 // log_debug("sco rx count %u", conn->sco_rx_count);
3353                 if (conn->sco_rx_count == 10) {
3354                     // use first timestamp as is and pretent it just started
3355                     conn->sco_rx_ms = now;
3356                     conn->sco_rx_valid = 1;
3357                     conn->sco_rx_count = 0;
3358                     sco_schedule_tx(conn);
3359                 }
3360             } else {
3361                 // track expected arrival timme
3362                 conn->sco_rx_count++;
3363                 conn->sco_rx_ms += 7;
3364                 int delta = (int32_t) (now - conn->sco_rx_ms);
3365                 if (delta > 0){
3366                     conn->sco_rx_ms++;
3367                 }
3368                 // log_debug("sco rx %u", conn->sco_rx_ms);
3369                 sco_schedule_tx(conn);
3370             }
3371         }
3372     }
3373 #endif
3374 
3375     // deliver to app
3376     if (hci_stack->sco_packet_handler) {
3377         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3378     }
3379 
3380 #ifdef HAVE_SCO_TRANSPORT
3381     // We can send one packet for each received packet
3382     conn->sco_tx_ready++;
3383     hci_notify_if_sco_can_send_now();
3384 #endif
3385 
3386 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3387     conn->num_packets_completed++;
3388     hci_stack->host_completed_packets = 1;
3389     hci_run();
3390 #endif
3391 }
3392 #endif
3393 
3394 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3395     hci_dump_packet(packet_type, 1, packet, size);
3396     switch (packet_type) {
3397         case HCI_EVENT_PACKET:
3398             event_handler(packet, size);
3399             break;
3400         case HCI_ACL_DATA_PACKET:
3401             acl_handler(packet, size);
3402             break;
3403 #ifdef ENABLE_CLASSIC
3404         case HCI_SCO_DATA_PACKET:
3405             sco_handler(packet, size);
3406             break;
3407 #endif
3408         default:
3409             break;
3410     }
3411 }
3412 
3413 /**
3414  * @brief Add event packet handler.
3415  */
3416 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3417     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3418 }
3419 
3420 
3421 /** Register HCI packet handlers */
3422 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3423     hci_stack->acl_packet_handler = handler;
3424 }
3425 
3426 #ifdef ENABLE_CLASSIC
3427 /**
3428  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3429  */
3430 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3431     hci_stack->sco_packet_handler = handler;
3432 }
3433 #endif
3434 
3435 static void hci_state_reset(void){
3436     // no connections yet
3437     hci_stack->connections = NULL;
3438 
3439     // keep discoverable/connectable as this has been requested by the client(s)
3440     // hci_stack->discoverable = 0;
3441     // hci_stack->connectable = 0;
3442     // hci_stack->bondable = 1;
3443     // hci_stack->own_addr_type = 0;
3444 
3445     // buffer is free
3446     hci_stack->hci_packet_buffer_reserved = false;
3447 
3448     // no pending cmds
3449     hci_stack->decline_reason = 0;
3450 
3451     hci_stack->secure_connections_active = false;
3452 
3453 #ifdef ENABLE_CLASSIC
3454     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3455     hci_stack->gap_tasks =
3456             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3457             GAP_TASK_SET_CLASS_OF_DEVICE |
3458             GAP_TASK_SET_LOCAL_NAME |
3459             GAP_TASK_SET_EIR_DATA |
3460             GAP_TASK_WRITE_SCAN_ENABLE;
3461 #endif
3462 
3463 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3464     hci_stack->classic_read_local_oob_data = true;
3465     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3466 #endif
3467 
3468     // LE
3469 #ifdef ENABLE_BLE
3470     memset(hci_stack->le_random_address, 0, 6);
3471     hci_stack->le_random_address_set = 0;
3472 #endif
3473 #ifdef ENABLE_LE_CENTRAL
3474     hci_stack->le_scanning_active  = false;
3475     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3476     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3477     hci_stack->le_whitelist_capacity = 0;
3478 #endif
3479 #ifdef ENABLE_LE_PERIPHERAL
3480     hci_stack->le_advertisements_active = false;
3481     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3482         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3483     }
3484     if (hci_stack->le_advertisements_data != NULL){
3485         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3486     }
3487 #endif
3488 }
3489 
3490 #ifdef ENABLE_CLASSIC
3491 /**
3492  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3493  */
3494 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3495     // store and open remote device db
3496     hci_stack->link_key_db = link_key_db;
3497     if (hci_stack->link_key_db) {
3498         hci_stack->link_key_db->open();
3499     }
3500 }
3501 #endif
3502 
3503 void hci_init(const hci_transport_t *transport, const void *config){
3504 
3505 #ifdef HAVE_MALLOC
3506     if (!hci_stack) {
3507         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3508     }
3509 #else
3510     hci_stack = &hci_stack_static;
3511 #endif
3512     memset(hci_stack, 0, sizeof(hci_stack_t));
3513 
3514     // reference to use transport layer implementation
3515     hci_stack->hci_transport = transport;
3516 
3517     // reference to used config
3518     hci_stack->config = config;
3519 
3520     // setup pointer for outgoing packet buffer
3521     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3522 
3523     // max acl payload size defined in config.h
3524     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3525 
3526     // register packet handlers with transport
3527     transport->register_packet_handler(&packet_handler);
3528 
3529     hci_stack->state = HCI_STATE_OFF;
3530 
3531     // class of device
3532     hci_stack->class_of_device = 0x007a020c; // Smartphone
3533 
3534     // bondable by default
3535     hci_stack->bondable = 1;
3536 
3537 #ifdef ENABLE_CLASSIC
3538     // classic name
3539     hci_stack->local_name = default_classic_name;
3540 
3541     // Master slave policy
3542     hci_stack->master_slave_policy = 1;
3543 
3544     // Allow Role Switch
3545     hci_stack->allow_role_switch = 1;
3546 
3547     // Default / minimum security level = 2
3548     hci_stack->gap_security_level = LEVEL_2;
3549 
3550     // Default Security Mode 4
3551     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3552 
3553     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3554     hci_stack->gap_required_encyrption_key_size = 7;
3555 
3556     // Link Supervision Timeout
3557     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3558 
3559 #endif
3560 
3561     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3562     hci_stack->ssp_enable = 1;
3563     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3564     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3565     hci_stack->ssp_auto_accept = 1;
3566 
3567     // Secure Connections: enable (requires support from Controller)
3568     hci_stack->secure_connections_enable = true;
3569 
3570     // voice setting - signed 16 bit pcm data with CVSD over the air
3571     hci_stack->sco_voice_setting = 0x60;
3572 
3573 #ifdef ENABLE_LE_CENTRAL
3574     // connection parameter to use for outgoing connections
3575     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3576     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3577     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3578     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3579     hci_stack->le_connection_latency      = 4;         // 4
3580     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3581     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3582     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3583 
3584     // default LE Scanning
3585     hci_stack->le_scan_type     =   0x1; // active
3586     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3587     hci_stack->le_scan_window   =  0x30; //  30 ms
3588 #endif
3589 
3590 #ifdef ENABLE_LE_PERIPHERAL
3591     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3592 #endif
3593 
3594     // connection parameter range used to answer connection parameter update requests in l2cap
3595     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3596     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3597     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3598     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3599     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3600     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3601 
3602     hci_state_reset();
3603 }
3604 
3605 void hci_deinit(void){
3606 #ifdef HAVE_MALLOC
3607     if (hci_stack) {
3608         free(hci_stack);
3609     }
3610 #endif
3611     hci_stack = NULL;
3612 
3613 #ifdef ENABLE_CLASSIC
3614     disable_l2cap_timeouts = 0;
3615 #endif
3616 }
3617 
3618 /**
3619  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3620  */
3621 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3622     hci_stack->chipset = chipset_driver;
3623 
3624     // reset chipset driver - init is also called on power_up
3625     if (hci_stack->chipset && hci_stack->chipset->init){
3626         hci_stack->chipset->init(hci_stack->config);
3627     }
3628 }
3629 
3630 /**
3631  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3632  */
3633 void hci_set_control(const btstack_control_t *hardware_control){
3634     // references to used control implementation
3635     hci_stack->control = hardware_control;
3636     // init with transport config
3637     hardware_control->init(hci_stack->config);
3638 }
3639 
3640 void hci_close(void){
3641 
3642 #ifdef ENABLE_CLASSIC
3643     // close remote device db
3644     if (hci_stack->link_key_db) {
3645         hci_stack->link_key_db->close();
3646     }
3647 #endif
3648 
3649     btstack_linked_list_iterator_t lit;
3650     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3651     while (btstack_linked_list_iterator_has_next(&lit)){
3652         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3653         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3654         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3655         hci_shutdown_connection(connection);
3656     }
3657 
3658     hci_power_control(HCI_POWER_OFF);
3659 
3660 #ifdef HAVE_MALLOC
3661     free(hci_stack);
3662 #endif
3663     hci_stack = NULL;
3664 }
3665 
3666 #ifdef HAVE_SCO_TRANSPORT
3667 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3668     hci_stack->sco_transport = sco_transport;
3669     sco_transport->register_packet_handler(&packet_handler);
3670 }
3671 #endif
3672 
3673 #ifdef ENABLE_CLASSIC
3674 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3675     // validate ranage and set
3676     if (encryption_key_size < 7)  return;
3677     if (encryption_key_size > 16) return;
3678     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3679 }
3680 
3681 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3682     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3683         hci_stack->gap_security_mode = security_mode;
3684         return ERROR_CODE_SUCCESS;
3685     } else {
3686         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3687     }
3688 }
3689 
3690 gap_security_mode_t gap_get_security_mode(void){
3691     return hci_stack->gap_security_mode;
3692 }
3693 
3694 void gap_set_security_level(gap_security_level_t security_level){
3695     hci_stack->gap_security_level = security_level;
3696 }
3697 
3698 gap_security_level_t gap_get_security_level(void){
3699     if (hci_stack->gap_secure_connections_only_mode){
3700         return LEVEL_4;
3701     }
3702     return hci_stack->gap_security_level;
3703 }
3704 
3705 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3706     hci_stack->gap_minimal_service_security_level = security_level;
3707 }
3708 
3709 void gap_set_secure_connections_only_mode(bool enable){
3710     hci_stack->gap_secure_connections_only_mode = enable;
3711 }
3712 
3713 bool gap_get_secure_connections_only_mode(void){
3714     return hci_stack->gap_secure_connections_only_mode;
3715 }
3716 #endif
3717 
3718 #ifdef ENABLE_CLASSIC
3719 void gap_set_class_of_device(uint32_t class_of_device){
3720     hci_stack->class_of_device = class_of_device;
3721     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3722     hci_run();
3723 }
3724 
3725 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3726     hci_stack->default_link_policy_settings = default_link_policy_settings;
3727     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3728     hci_run();
3729 }
3730 
3731 void gap_set_allow_role_switch(bool allow_role_switch){
3732     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3733 }
3734 
3735 uint8_t hci_get_allow_role_switch(void){
3736     return  hci_stack->allow_role_switch;
3737 }
3738 
3739 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3740     hci_stack->link_supervision_timeout = link_supervision_timeout;
3741 }
3742 
3743 void hci_disable_l2cap_timeout_check(void){
3744     disable_l2cap_timeouts = 1;
3745 }
3746 #endif
3747 
3748 #ifndef HAVE_HOST_CONTROLLER_API
3749 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3750 void hci_set_bd_addr(bd_addr_t addr){
3751     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3752     hci_stack->custom_bd_addr_set = 1;
3753 }
3754 #endif
3755 
3756 // State-Module-Driver overview
3757 // state                    module  low-level
3758 // HCI_STATE_OFF             off      close
3759 // HCI_STATE_INITIALIZING,   on       open
3760 // HCI_STATE_WORKING,        on       open
3761 // HCI_STATE_HALTING,        on       open
3762 // HCI_STATE_SLEEPING,    off/sleep   close
3763 // HCI_STATE_FALLING_ASLEEP  on       open
3764 
3765 static int hci_power_control_on(void){
3766 
3767     // power on
3768     int err = 0;
3769     if (hci_stack->control && hci_stack->control->on){
3770         err = (*hci_stack->control->on)();
3771     }
3772     if (err){
3773         log_error( "POWER_ON failed");
3774         hci_emit_hci_open_failed();
3775         return err;
3776     }
3777 
3778     // int chipset driver
3779     if (hci_stack->chipset && hci_stack->chipset->init){
3780         hci_stack->chipset->init(hci_stack->config);
3781     }
3782 
3783     // init transport
3784     if (hci_stack->hci_transport->init){
3785         hci_stack->hci_transport->init(hci_stack->config);
3786     }
3787 
3788     // open transport
3789     err = hci_stack->hci_transport->open();
3790     if (err){
3791         log_error( "HCI_INIT failed, turning Bluetooth off again");
3792         if (hci_stack->control && hci_stack->control->off){
3793             (*hci_stack->control->off)();
3794         }
3795         hci_emit_hci_open_failed();
3796         return err;
3797     }
3798     return 0;
3799 }
3800 
3801 static void hci_power_control_off(void){
3802 
3803     log_info("hci_power_control_off");
3804 
3805     // close low-level device
3806     hci_stack->hci_transport->close();
3807 
3808     log_info("hci_power_control_off - hci_transport closed");
3809 
3810     // power off
3811     if (hci_stack->control && hci_stack->control->off){
3812         (*hci_stack->control->off)();
3813     }
3814 
3815     log_info("hci_power_control_off - control closed");
3816 
3817     hci_stack->state = HCI_STATE_OFF;
3818 }
3819 
3820 static void hci_power_control_sleep(void){
3821 
3822     log_info("hci_power_control_sleep");
3823 
3824 #if 0
3825     // don't close serial port during sleep
3826 
3827     // close low-level device
3828     hci_stack->hci_transport->close(hci_stack->config);
3829 #endif
3830 
3831     // sleep mode
3832     if (hci_stack->control && hci_stack->control->sleep){
3833         (*hci_stack->control->sleep)();
3834     }
3835 
3836     hci_stack->state = HCI_STATE_SLEEPING;
3837 }
3838 
3839 static int hci_power_control_wake(void){
3840 
3841     log_info("hci_power_control_wake");
3842 
3843     // wake on
3844     if (hci_stack->control && hci_stack->control->wake){
3845         (*hci_stack->control->wake)();
3846     }
3847 
3848 #if 0
3849     // open low-level device
3850     int err = hci_stack->hci_transport->open(hci_stack->config);
3851     if (err){
3852         log_error( "HCI_INIT failed, turning Bluetooth off again");
3853         if (hci_stack->control && hci_stack->control->off){
3854             (*hci_stack->control->off)();
3855         }
3856         hci_emit_hci_open_failed();
3857         return err;
3858     }
3859 #endif
3860 
3861     return 0;
3862 }
3863 
3864 static void hci_power_transition_to_initializing(void){
3865     // set up state machine
3866     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3867     hci_stack->hci_packet_buffer_reserved = false;
3868     hci_stack->state = HCI_STATE_INITIALIZING;
3869     hci_stack->substate = HCI_INIT_SEND_RESET;
3870 }
3871 
3872 // returns error
3873 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3874     int err;
3875     switch (power_mode){
3876         case HCI_POWER_ON:
3877             err = hci_power_control_on();
3878             if (err != 0) {
3879                 log_error("hci_power_control_on() error %d", err);
3880                 return err;
3881             }
3882             hci_power_transition_to_initializing();
3883             break;
3884         case HCI_POWER_OFF:
3885             // do nothing
3886             break;
3887         case HCI_POWER_SLEEP:
3888             // do nothing (with SLEEP == OFF)
3889             break;
3890         default:
3891             btstack_assert(false);
3892             break;
3893     }
3894     return ERROR_CODE_SUCCESS;
3895 }
3896 
3897 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3898     switch (power_mode){
3899         case HCI_POWER_ON:
3900             // do nothing
3901             break;
3902         case HCI_POWER_OFF:
3903             // no connections yet, just turn it off
3904             hci_power_control_off();
3905             break;
3906         case HCI_POWER_SLEEP:
3907             // no connections yet, just turn it off
3908             hci_power_control_sleep();
3909             break;
3910         default:
3911             btstack_assert(false);
3912             break;
3913     }
3914     return ERROR_CODE_SUCCESS;
3915 }
3916 
3917 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3918     switch (power_mode){
3919         case HCI_POWER_ON:
3920             // do nothing
3921             break;
3922         case HCI_POWER_OFF:
3923             // see hci_run
3924             hci_stack->state = HCI_STATE_HALTING;
3925             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3926             break;
3927         case HCI_POWER_SLEEP:
3928             // see hci_run
3929             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3930             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3931             break;
3932         default:
3933             btstack_assert(false);
3934             break;
3935     }
3936     return ERROR_CODE_SUCCESS;
3937 }
3938 
3939 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3940     switch (power_mode){
3941         case HCI_POWER_ON:
3942             hci_power_transition_to_initializing();
3943             break;
3944         case HCI_POWER_OFF:
3945             // do nothing
3946             break;
3947         case HCI_POWER_SLEEP:
3948             // see hci_run
3949             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3950             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3951             break;
3952         default:
3953             btstack_assert(false);
3954             break;
3955     }
3956     return ERROR_CODE_SUCCESS;
3957 }
3958 
3959 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3960     switch (power_mode){
3961         case HCI_POWER_ON:
3962             hci_power_transition_to_initializing();
3963             break;
3964         case HCI_POWER_OFF:
3965             // see hci_run
3966             hci_stack->state = HCI_STATE_HALTING;
3967             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3968             break;
3969         case HCI_POWER_SLEEP:
3970             // do nothing
3971             break;
3972         default:
3973             btstack_assert(false);
3974             break;
3975     }
3976     return ERROR_CODE_SUCCESS;
3977 }
3978 
3979 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3980     int err;
3981     switch (power_mode){
3982         case HCI_POWER_ON:
3983             err = hci_power_control_wake();
3984             if (err) return err;
3985             hci_power_transition_to_initializing();
3986             break;
3987         case HCI_POWER_OFF:
3988             hci_stack->state = HCI_STATE_HALTING;
3989             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3990             break;
3991         case HCI_POWER_SLEEP:
3992             // do nothing
3993             break;
3994         default:
3995             btstack_assert(false);
3996             break;
3997     }
3998     return ERROR_CODE_SUCCESS;
3999 }
4000 
4001 int hci_power_control(HCI_POWER_MODE power_mode){
4002     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
4003     int err = 0;
4004     switch (hci_stack->state){
4005         case HCI_STATE_OFF:
4006             err = hci_power_control_state_off(power_mode);
4007             break;
4008         case HCI_STATE_INITIALIZING:
4009             err = hci_power_control_state_initializing(power_mode);
4010             break;
4011         case HCI_STATE_WORKING:
4012             err = hci_power_control_state_working(power_mode);
4013             break;
4014         case HCI_STATE_HALTING:
4015             err = hci_power_control_state_halting(power_mode);
4016             break;
4017         case HCI_STATE_FALLING_ASLEEP:
4018             err = hci_power_control_state_falling_asleep(power_mode);
4019             break;
4020         case HCI_STATE_SLEEPING:
4021             err = hci_power_control_state_sleeping(power_mode);
4022             break;
4023         default:
4024             btstack_assert(false);
4025             break;
4026     }
4027     if (err != 0){
4028         return err;
4029     }
4030 
4031     // create internal event
4032 	hci_emit_state();
4033 
4034 	// trigger next/first action
4035 	hci_run();
4036 
4037     return 0;
4038 }
4039 
4040 
4041 #ifdef ENABLE_CLASSIC
4042 
4043 static void hci_update_scan_enable(void){
4044     // 2 = page scan, 1 = inq scan
4045     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4046     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4047     hci_run();
4048 }
4049 
4050 void gap_discoverable_control(uint8_t enable){
4051     if (enable) enable = 1; // normalize argument
4052 
4053     if (hci_stack->discoverable == enable){
4054         hci_emit_discoverable_enabled(hci_stack->discoverable);
4055         return;
4056     }
4057 
4058     hci_stack->discoverable = enable;
4059     hci_update_scan_enable();
4060 }
4061 
4062 void gap_connectable_control(uint8_t enable){
4063     if (enable) enable = 1; // normalize argument
4064 
4065     // don't emit event
4066     if (hci_stack->connectable == enable) return;
4067 
4068     hci_stack->connectable = enable;
4069     hci_update_scan_enable();
4070 }
4071 #endif
4072 
4073 void gap_local_bd_addr(bd_addr_t address_buffer){
4074     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4075 }
4076 
4077 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4078 static void hci_host_num_completed_packets(void){
4079 
4080     // create packet manually as arrays are not supported and num_commands should not get reduced
4081     hci_reserve_packet_buffer();
4082     uint8_t * packet = hci_get_outgoing_packet_buffer();
4083 
4084     uint16_t size = 0;
4085     uint16_t num_handles = 0;
4086     packet[size++] = 0x35;
4087     packet[size++] = 0x0c;
4088     size++;  // skip param len
4089     size++;  // skip num handles
4090 
4091     // add { handle, packets } entries
4092     btstack_linked_item_t * it;
4093     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4094         hci_connection_t * connection = (hci_connection_t *) it;
4095         if (connection->num_packets_completed){
4096             little_endian_store_16(packet, size, connection->con_handle);
4097             size += 2;
4098             little_endian_store_16(packet, size, connection->num_packets_completed);
4099             size += 2;
4100             //
4101             num_handles++;
4102             connection->num_packets_completed = 0;
4103         }
4104     }
4105 
4106     packet[2] = size - 3;
4107     packet[3] = num_handles;
4108 
4109     hci_stack->host_completed_packets = 0;
4110 
4111     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4112     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4113 
4114     // release packet buffer for synchronous transport implementations
4115     if (hci_transport_synchronous()){
4116         hci_release_packet_buffer();
4117         hci_emit_transport_packet_sent();
4118     }
4119 }
4120 #endif
4121 
4122 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4123     UNUSED(ds);
4124     hci_stack->substate = HCI_HALTING_CLOSE;
4125     // allow packet handlers to defer final shutdown
4126     hci_emit_state();
4127     hci_run();
4128 }
4129 
4130 static bool hci_run_acl_fragments(void){
4131     if (hci_stack->acl_fragmentation_total_size > 0u) {
4132         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4133         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4134         if (connection) {
4135             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4136                 hci_send_acl_packet_fragments(connection);
4137                 return true;
4138             }
4139         } else {
4140             // connection gone -> discard further fragments
4141             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4142             hci_stack->acl_fragmentation_total_size = 0;
4143             hci_stack->acl_fragmentation_pos = 0;
4144         }
4145     }
4146     return false;
4147 }
4148 
4149 #ifdef ENABLE_CLASSIC
4150 static bool hci_run_general_gap_classic(void){
4151 
4152     // assert stack is working and classic is active
4153     if (hci_classic_supported() == false)      return false;
4154     if (hci_stack->state != HCI_STATE_WORKING) return false;
4155 
4156     // decline incoming connections
4157     if (hci_stack->decline_reason){
4158         uint8_t reason = hci_stack->decline_reason;
4159         hci_stack->decline_reason = 0;
4160         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4161         return true;
4162     }
4163 
4164     if (hci_stack->gap_tasks != 0){
4165         hci_run_gap_tasks_classic();
4166         return true;
4167     }
4168 
4169     // start/stop inquiry
4170     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4171         uint8_t duration = hci_stack->inquiry_state;
4172         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4173         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4174         return true;
4175     }
4176     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4177         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4178         hci_send_cmd(&hci_inquiry_cancel);
4179         return true;
4180     }
4181     // remote name request
4182     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4183         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4184         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4185                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4186         return true;
4187     }
4188 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4189     // Local OOB data
4190     if (hci_stack->classic_read_local_oob_data){
4191         hci_stack->classic_read_local_oob_data = false;
4192         if (hci_stack->local_supported_commands[1] & 0x10u){
4193             hci_send_cmd(&hci_read_local_extended_oob_data);
4194         } else {
4195             hci_send_cmd(&hci_read_local_oob_data);
4196         }
4197     }
4198 #endif
4199     // pairing
4200     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4201         uint8_t state = hci_stack->gap_pairing_state;
4202         uint8_t pin_code[16];
4203         switch (state){
4204             case GAP_PAIRING_STATE_SEND_PIN:
4205                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4206                 memset(pin_code, 0, 16);
4207                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4208                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4209                 break;
4210             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4211                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4212                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4213                 break;
4214             case GAP_PAIRING_STATE_SEND_PASSKEY:
4215                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4216                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4217                 break;
4218             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4219                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4220                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4221                 break;
4222             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4223                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4224                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4225                 break;
4226             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4227                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4228                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4229                 break;
4230             default:
4231                 break;
4232         }
4233         return true;
4234     }
4235     return false;
4236 }
4237 #endif
4238 
4239 #ifdef ENABLE_BLE
4240 static bool hci_run_general_gap_le(void){
4241 
4242     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4243 
4244     if (hci_stack->state != HCI_STATE_WORKING) return false;
4245     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4246 
4247 
4248     // Phase 1: collect what to stop
4249 
4250     bool scanning_stop = false;
4251     bool connecting_stop = false;
4252     bool advertising_stop = false;
4253 
4254 #ifndef ENABLE_LE_CENTRAL
4255     UNUSED(scanning_stop);
4256     UNUSED(connecting_stop);
4257 #endif
4258 #ifndef ENABLE_LE_PERIPHERAL
4259     UNUSED(advertising_stop);
4260 #endif
4261 
4262     // check if whitelist needs modification
4263     bool whitelist_modification_pending = false;
4264     btstack_linked_list_iterator_t lit;
4265     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4266     while (btstack_linked_list_iterator_has_next(&lit)){
4267         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4268         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4269             whitelist_modification_pending = true;
4270             break;
4271         }
4272     }
4273     // check if resolving list needs modification
4274     bool resolving_list_modification_pending = false;
4275 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4276     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4277 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4278         resolving_list_modification_pending = true;
4279     }
4280 #endif
4281 
4282 #ifdef ENABLE_LE_CENTRAL
4283     // scanning control
4284     if (hci_stack->le_scanning_active) {
4285         // stop if:
4286         // - parameter change required
4287         // - it's disabled
4288         // - whitelist change required but used for scanning
4289         // - resolving list modified
4290         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4291         if ((hci_stack->le_scanning_param_update) ||
4292             !hci_stack->le_scanning_enabled ||
4293             scanning_uses_whitelist ||
4294             resolving_list_modification_pending){
4295 
4296             scanning_stop = true;
4297         }
4298     }
4299 #endif
4300 
4301 #ifdef ENABLE_LE_CENTRAL
4302     // connecting control
4303     bool connecting_with_whitelist;
4304     switch (hci_stack->le_connecting_state){
4305         case LE_CONNECTING_DIRECT:
4306         case LE_CONNECTING_WHITELIST:
4307             // stop connecting if:
4308             // - connecting uses white and whitelist modification pending
4309             // - if it got disabled
4310             // - resolving list modified
4311             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4312             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4313                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4314                 resolving_list_modification_pending) {
4315 
4316                 connecting_stop = true;
4317             }
4318             break;
4319         default:
4320             break;
4321     }
4322 #endif
4323 
4324 #ifdef ENABLE_LE_PERIPHERAL
4325     // le advertisement control
4326     if (hci_stack->le_advertisements_active){
4327         // stop if:
4328         // - parameter change required
4329         // - it's disabled
4330         // - whitelist change required but used for advertisement filter policy
4331         // - resolving list modified
4332         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4333         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4334         if (advertising_change ||
4335             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4336             (advertising_uses_whitelist & whitelist_modification_pending) ||
4337             resolving_list_modification_pending) {
4338 
4339             advertising_stop = true;
4340         }
4341     }
4342 #endif
4343 
4344 
4345     // Phase 2: stop everything that should be off during modifications
4346 
4347 #ifdef ENABLE_LE_CENTRAL
4348     if (scanning_stop){
4349         hci_stack->le_scanning_active = false;
4350         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4351         return true;
4352     }
4353 #endif
4354 
4355 #ifdef ENABLE_LE_CENTRAL
4356     if (connecting_stop){
4357         hci_send_cmd(&hci_le_create_connection_cancel);
4358         return true;
4359     }
4360 #endif
4361 
4362 #ifdef ENABLE_LE_PERIPHERAL
4363     if (advertising_stop){
4364         hci_stack->le_advertisements_active = false;
4365         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4366         return true;
4367     }
4368 #endif
4369 
4370     // Phase 3: modify
4371 
4372 #ifdef ENABLE_LE_CENTRAL
4373     if (hci_stack->le_scanning_param_update){
4374         hci_stack->le_scanning_param_update = false;
4375         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4376                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4377         return true;
4378     }
4379 #endif
4380 
4381 #ifdef ENABLE_LE_PERIPHERAL
4382     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4383         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4384         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4385         hci_send_cmd(&hci_le_set_advertising_parameters,
4386                      hci_stack->le_advertisements_interval_min,
4387                      hci_stack->le_advertisements_interval_max,
4388                      hci_stack->le_advertisements_type,
4389                      hci_stack->le_advertisements_own_addr_type,
4390                      hci_stack->le_advertisements_direct_address_type,
4391                      hci_stack->le_advertisements_direct_address,
4392                      hci_stack->le_advertisements_channel_map,
4393                      hci_stack->le_advertisements_filter_policy);
4394         return true;
4395     }
4396     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4397         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4398         uint8_t adv_data_clean[31];
4399         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4400         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4401                      hci_stack->le_advertisements_data_len);
4402         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4403         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4404         return true;
4405     }
4406     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4407         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4408         uint8_t scan_data_clean[31];
4409         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4410         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4411                      hci_stack->le_scan_response_data_len);
4412         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4413         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4414         return true;
4415     }
4416 #endif
4417 
4418 
4419 #ifdef ENABLE_LE_CENTRAL
4420     // if connect with whitelist was active and is not cancelled yet, wait until next time
4421     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4422 #endif
4423 
4424     // LE Whitelist Management
4425     if (whitelist_modification_pending){
4426         // add/remove entries
4427         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4428         while (btstack_linked_list_iterator_has_next(&lit)){
4429             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4430 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4431 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4432 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4433 				return true;
4434 			}
4435             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4436 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4437                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4438                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4439                 return true;
4440             }
4441             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4442 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4443 				btstack_memory_whitelist_entry_free(entry);
4444             }
4445         }
4446     }
4447 
4448 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4449     // LE Resolving List Management
4450     if (resolving_list_supported) {
4451 		uint16_t i;
4452 		switch (hci_stack->le_resolving_list_state) {
4453 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4454 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4455 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4456 				return true;
4457 			case LE_RESOLVING_LIST_READ_SIZE:
4458 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4459 				hci_send_cmd(&hci_le_read_resolving_list_size);
4460 				return true;
4461 			case LE_RESOLVING_LIST_SEND_CLEAR:
4462 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4463 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4464 							  sizeof(hci_stack->le_resolving_list_add_entries));
4465 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4466 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4467 				hci_send_cmd(&hci_le_clear_resolving_list);
4468 				return true;
4469 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4470 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4471 					uint8_t offset = i >> 3;
4472 					uint8_t mask = 1 << (i & 7);
4473 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4474 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4475 					bd_addr_t peer_identity_addreses;
4476 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4477 					sm_key_t peer_irk;
4478 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4479 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4480 
4481 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4482 					// trigger whitelist entry 'update' (work around for controller bug)
4483 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4484 					while (btstack_linked_list_iterator_has_next(&lit)) {
4485 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4486 						if (entry->address_type != peer_identity_addr_type) continue;
4487 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4488 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4489 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4490 					}
4491 #endif
4492 
4493 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4494 								 peer_identity_addreses);
4495 					return true;
4496 				}
4497 
4498 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4499 
4500 				/* fall through */
4501 
4502 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4503 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4504 					uint8_t offset = i >> 3;
4505 					uint8_t mask = 1 << (i & 7);
4506 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4507 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4508 					bd_addr_t peer_identity_addreses;
4509 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4510 					sm_key_t peer_irk;
4511 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4512 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4513 					const uint8_t *local_irk = gap_get_persistent_irk();
4514 					// command uses format specifier 'P' that stores 16-byte value without flip
4515 					uint8_t local_irk_flipped[16];
4516 					uint8_t peer_irk_flipped[16];
4517 					reverse_128(local_irk, local_irk_flipped);
4518 					reverse_128(peer_irk, peer_irk_flipped);
4519 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4520 								 peer_irk_flipped, local_irk_flipped);
4521 					return true;
4522 				}
4523 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4524 				break;
4525 
4526 			default:
4527 				break;
4528 		}
4529 	}
4530     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4531 #endif
4532 
4533     // Phase 4: restore state
4534 
4535 #ifdef ENABLE_LE_CENTRAL
4536     // re-start scanning
4537     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4538         hci_stack->le_scanning_active = true;
4539         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4540         return true;
4541     }
4542 #endif
4543 
4544 #ifdef ENABLE_LE_CENTRAL
4545     // re-start connecting
4546     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4547         bd_addr_t null_addr;
4548         memset(null_addr, 0, 6);
4549         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4550         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4551         hci_send_cmd(&hci_le_create_connection,
4552                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4553                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4554                      1,         // use whitelist
4555                      0,         // peer address type
4556                      null_addr, // peer bd addr
4557                      hci_stack->le_connection_own_addr_type,   // our addr type:
4558                      hci_stack->le_connection_interval_min,    // conn interval min
4559                      hci_stack->le_connection_interval_max,    // conn interval max
4560                      hci_stack->le_connection_latency,         // conn latency
4561                      hci_stack->le_supervision_timeout,        // conn latency
4562                      hci_stack->le_minimum_ce_length,          // min ce length
4563                      hci_stack->le_maximum_ce_length           // max ce length
4564         );
4565         return true;
4566     }
4567 #endif
4568 
4569 #ifdef ENABLE_LE_PERIPHERAL
4570     // re-start advertising
4571     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4572         // check if advertisements should be enabled given
4573         hci_stack->le_advertisements_active = true;
4574         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4575         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4576         return true;
4577     }
4578 #endif
4579 
4580     return false;
4581 }
4582 #endif
4583 
4584 static bool hci_run_general_pending_commands(void){
4585     btstack_linked_item_t * it;
4586     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4587         hci_connection_t * connection = (hci_connection_t *) it;
4588 
4589         switch(connection->state){
4590             case SEND_CREATE_CONNECTION:
4591                 switch(connection->address_type){
4592 #ifdef ENABLE_CLASSIC
4593                     case BD_ADDR_TYPE_ACL:
4594                         log_info("sending hci_create_connection");
4595                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4596                         break;
4597 #endif
4598                     default:
4599 #ifdef ENABLE_BLE
4600 #ifdef ENABLE_LE_CENTRAL
4601                         log_info("sending hci_le_create_connection");
4602                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4603                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4604                         hci_send_cmd(&hci_le_create_connection,
4605                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4606                                      hci_stack->le_connection_scan_window,      // conn scan windows
4607                                      0,         // don't use whitelist
4608                                      connection->address_type, // peer address type
4609                                      connection->address,      // peer bd addr
4610                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4611                                      hci_stack->le_connection_interval_min,    // conn interval min
4612                                      hci_stack->le_connection_interval_max,    // conn interval max
4613                                      hci_stack->le_connection_latency,         // conn latency
4614                                      hci_stack->le_supervision_timeout,        // conn latency
4615                                      hci_stack->le_minimum_ce_length,          // min ce length
4616                                      hci_stack->le_maximum_ce_length          // max ce length
4617                         );
4618                         connection->state = SENT_CREATE_CONNECTION;
4619 #endif
4620 #endif
4621                         break;
4622                 }
4623                 return true;
4624 
4625 #ifdef ENABLE_CLASSIC
4626             case RECEIVED_CONNECTION_REQUEST:
4627                 connection->role  = HCI_ROLE_SLAVE;
4628                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4629                     log_info("sending hci_accept_connection_request");
4630                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4631                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4632                 }
4633                 return true;
4634 #endif
4635 
4636 #ifdef ENABLE_BLE
4637 #ifdef ENABLE_LE_CENTRAL
4638             case SEND_CANCEL_CONNECTION:
4639                 connection->state = SENT_CANCEL_CONNECTION;
4640                 hci_send_cmd(&hci_le_create_connection_cancel);
4641                 return true;
4642 #endif
4643 #endif
4644             case SEND_DISCONNECT:
4645                 connection->state = SENT_DISCONNECT;
4646                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4647                 return true;
4648 
4649             default:
4650                 break;
4651         }
4652 
4653         // no further commands if connection is about to get shut down
4654         if (connection->state == SENT_DISCONNECT) continue;
4655 
4656         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4657             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4658             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4659             return true;
4660         }
4661 
4662 #ifdef ENABLE_CLASSIC
4663 
4664         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4665             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4666             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4667             return true;
4668         }
4669 
4670         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4671             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4672             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4673             return true;
4674         }
4675 
4676         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4677             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4678             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4679             return true;
4680         }
4681 
4682         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4683             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4684             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4685             return true;
4686         }
4687 
4688         // Handling link key request requires remote supported features
4689         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4690             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4691             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4692 
4693             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4694             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4695             if (have_link_key && security_level_sufficient){
4696                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4697             } else {
4698                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4699             }
4700             return true;
4701         }
4702 
4703         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4704             log_info("denying to pin request");
4705             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4706             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4707             return true;
4708         }
4709 
4710         // security assessment requires remote features
4711         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4712             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4713             hci_ssp_assess_security_on_io_cap_request(connection);
4714             // 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
4715         }
4716 
4717         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4718             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4719             // set authentication requirements:
4720             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4721             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4722             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4723             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4724                 authreq |= 1;
4725             }
4726             bool bonding = hci_stack->bondable;
4727             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4728                 // if we have received IO Cap Response, we're in responder role
4729                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4730                 if (bonding && !remote_bonding){
4731                     log_info("Remote not bonding, dropping local flag");
4732                     bonding = false;
4733                 }
4734             }
4735             if (bonding){
4736                 if (connection->bonding_flags & BONDING_DEDICATED){
4737                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4738                 } else {
4739                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4740                 }
4741             }
4742             uint8_t have_oob_data = 0;
4743 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4744             if (connection->classic_oob_c_192 != NULL){
4745                     have_oob_data |= 1;
4746             }
4747             if (connection->classic_oob_c_256 != NULL){
4748                 have_oob_data |= 2;
4749             }
4750 #endif
4751             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4752             return true;
4753         }
4754 
4755         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4756             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4757             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4758             return true;
4759         }
4760 
4761 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4762         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4763             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4764             const uint8_t zero[16] = { 0 };
4765             const uint8_t * r_192 = zero;
4766             const uint8_t * c_192 = zero;
4767             const uint8_t * r_256 = zero;
4768             const uint8_t * c_256 = zero;
4769             // verify P-256 OOB
4770             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4771                 c_256 = connection->classic_oob_c_256;
4772                 if (connection->classic_oob_r_256 != NULL) {
4773                     r_256 = connection->classic_oob_r_256;
4774                 }
4775             }
4776             // verify P-192 OOB
4777             if ((connection->classic_oob_c_192 != NULL)) {
4778                 c_192 = connection->classic_oob_c_192;
4779                 if (connection->classic_oob_r_192 != NULL) {
4780                     r_192 = connection->classic_oob_r_192;
4781                 }
4782             }
4783 
4784             // assess security
4785             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4786             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4787             if (need_level_4 && !can_reach_level_4){
4788                 log_info("Level 4 required, but not possible -> abort");
4789                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4790                 // send oob negative reply
4791                 c_256 = NULL;
4792                 c_192 = NULL;
4793             }
4794 
4795             // Reply
4796             if (c_256 != zero) {
4797                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4798             } else if (c_192 != zero){
4799                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4800             } else {
4801                 hci_stack->classic_oob_con_handle = connection->con_handle;
4802                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4803             }
4804             return true;
4805         }
4806 #endif
4807 
4808         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4809             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4810             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4811             return true;
4812         }
4813 
4814         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4815             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4816             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4817             return true;
4818         }
4819 
4820         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4821             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4822             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4823             return true;
4824         }
4825 
4826         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4827             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4828             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4829             connection->state = SENT_DISCONNECT;
4830             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4831             return true;
4832         }
4833 
4834         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4835             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4836             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4837             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4838             return true;
4839         }
4840 
4841         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4842             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4843             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4844             return true;
4845         }
4846         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4847             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4848             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4849             return true;
4850         }
4851 #endif
4852 
4853         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4854             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4855 #ifdef ENABLE_CLASSIC
4856             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4857 #endif
4858             if (connection->state != SENT_DISCONNECT){
4859                 connection->state = SENT_DISCONNECT;
4860                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4861                 return true;
4862             }
4863         }
4864 
4865 #ifdef ENABLE_CLASSIC
4866         uint16_t sniff_min_interval;
4867         switch (connection->sniff_min_interval){
4868             case 0:
4869                 break;
4870             case 0xffff:
4871                 connection->sniff_min_interval = 0;
4872                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4873                 return true;
4874             default:
4875                 sniff_min_interval = connection->sniff_min_interval;
4876                 connection->sniff_min_interval = 0;
4877                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4878                 return true;
4879         }
4880 
4881         if (connection->sniff_subrating_max_latency != 0xffff){
4882             uint16_t max_latency = connection->sniff_subrating_max_latency;
4883             connection->sniff_subrating_max_latency = 0;
4884             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4885             return true;
4886         }
4887 
4888         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4889             uint8_t service_type = (uint8_t) connection->qos_service_type;
4890             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4891             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);
4892             return true;
4893         }
4894 
4895         if (connection->request_role != HCI_ROLE_INVALID){
4896             hci_role_t role = connection->request_role;
4897             connection->request_role = HCI_ROLE_INVALID;
4898             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4899             return true;
4900         }
4901 #endif
4902 
4903 #ifdef ENABLE_BLE
4904         switch (connection->le_con_parameter_update_state){
4905             // response to L2CAP CON PARAMETER UPDATE REQUEST
4906             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4907                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4908                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4909                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4910                              0x0000, 0xffff);
4911                 return true;
4912             case CON_PARAMETER_UPDATE_REPLY:
4913                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4914                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4915                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4916                              0x0000, 0xffff);
4917                 return true;
4918             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4919                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4920                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4921                 return true;
4922             default:
4923                 break;
4924         }
4925         if (connection->le_phy_update_all_phys != 0xffu){
4926             uint8_t all_phys = connection->le_phy_update_all_phys;
4927             connection->le_phy_update_all_phys = 0xff;
4928             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);
4929             return true;
4930         }
4931 #endif
4932     }
4933     return false;
4934 }
4935 
4936 static void hci_run(void){
4937 
4938     bool done;
4939 
4940     // send continuation fragments first, as they block the prepared packet buffer
4941     done = hci_run_acl_fragments();
4942     if (done) return;
4943 
4944 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4945     // send host num completed packets next as they don't require num_cmd_packets > 0
4946     if (!hci_can_send_comand_packet_transport()) return;
4947     if (hci_stack->host_completed_packets){
4948         hci_host_num_completed_packets();
4949         return;
4950     }
4951 #endif
4952 
4953     if (!hci_can_send_command_packet_now()) return;
4954 
4955     // global/non-connection oriented commands
4956 
4957 
4958 #ifdef ENABLE_CLASSIC
4959     // general gap classic
4960     done = hci_run_general_gap_classic();
4961     if (done) return;
4962 #endif
4963 
4964 #ifdef ENABLE_BLE
4965     // general gap le
4966     done = hci_run_general_gap_le();
4967     if (done) return;
4968 #endif
4969 
4970     // send pending HCI commands
4971     done = hci_run_general_pending_commands();
4972     if (done) return;
4973 
4974     // stack state sub statemachines
4975     hci_connection_t * connection;
4976     switch (hci_stack->state){
4977         case HCI_STATE_INITIALIZING:
4978             hci_initializing_run();
4979             break;
4980 
4981         case HCI_STATE_HALTING:
4982 
4983             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4984             switch (hci_stack->substate){
4985                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4986                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4987 
4988 #ifdef ENABLE_BLE
4989 #ifdef ENABLE_LE_CENTRAL
4990                     // free whitelist entries
4991                     {
4992                         btstack_linked_list_iterator_t lit;
4993                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4994                         while (btstack_linked_list_iterator_has_next(&lit)){
4995                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4996                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4997                             btstack_memory_whitelist_entry_free(entry);
4998                         }
4999                     }
5000 #endif
5001 #endif
5002                     // close all open connections
5003                     connection =  (hci_connection_t *) hci_stack->connections;
5004                     if (connection){
5005                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5006                         if (!hci_can_send_command_packet_now()) return;
5007 
5008                         // check state
5009                         if (connection->state == SENT_DISCONNECT) return;
5010                         connection->state = SENT_DISCONNECT;
5011 
5012                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5013 
5014                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5015                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5016 
5017                         // ... which would be ignored anyway as we shutdown (free) the connection now
5018                         hci_shutdown_connection(connection);
5019 
5020                         // finally, send the disconnect command
5021                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5022                         return;
5023                     }
5024 
5025                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5026                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5027                         log_info("HCI_STATE_HALTING: wait 50 ms");
5028                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5029                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5030                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5031                         btstack_run_loop_add_timer(&hci_stack->timeout);
5032                         break;
5033                     }
5034 
5035                     /* fall through */
5036 
5037                 case HCI_HALTING_CLOSE:
5038                     log_info("HCI_STATE_HALTING, calling off");
5039 
5040                     // switch mode
5041                     hci_power_control_off();
5042 
5043                     log_info("HCI_STATE_HALTING, emitting state");
5044                     hci_emit_state();
5045                     log_info("HCI_STATE_HALTING, done");
5046                     break;
5047 
5048                 case HCI_HALTING_W4_TIMER:
5049                     // keep waiting
5050 
5051                     break;
5052                 default:
5053                     break;
5054             }
5055 
5056             break;
5057 
5058         case HCI_STATE_FALLING_ASLEEP:
5059             switch(hci_stack->substate) {
5060                 case HCI_FALLING_ASLEEP_DISCONNECT:
5061                     log_info("HCI_STATE_FALLING_ASLEEP");
5062                     // close all open connections
5063                     connection =  (hci_connection_t *) hci_stack->connections;
5064                     if (connection){
5065 
5066                         // send disconnect
5067                         if (!hci_can_send_command_packet_now()) return;
5068 
5069                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5070                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5071 
5072                         // send disconnected event right away - causes higher layer connections to get closed, too.
5073                         hci_shutdown_connection(connection);
5074                         return;
5075                     }
5076 
5077                     if (hci_classic_supported()){
5078                         // disable page and inquiry scan
5079                         if (!hci_can_send_command_packet_now()) return;
5080 
5081                         log_info("HCI_STATE_HALTING, disabling inq scans");
5082                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5083 
5084                         // continue in next sub state
5085                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5086                         break;
5087                     }
5088 
5089                     /* fall through */
5090 
5091                 case HCI_FALLING_ASLEEP_COMPLETE:
5092                     log_info("HCI_STATE_HALTING, calling sleep");
5093                     // switch mode
5094                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5095                     hci_emit_state();
5096                     break;
5097 
5098                 default:
5099                     break;
5100             }
5101             break;
5102 
5103         default:
5104             break;
5105     }
5106 }
5107 
5108 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5109     // house-keeping
5110 
5111 #ifdef ENABLE_CLASSIC
5112     bd_addr_t addr;
5113     hci_connection_t * conn;
5114 #endif
5115 #ifdef ENABLE_LE_CENTRAL
5116     uint8_t initiator_filter_policy;
5117 #endif
5118 
5119     uint16_t opcode = little_endian_read_16(packet, 0);
5120     switch (opcode) {
5121         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5122             hci_stack->loopback_mode = packet[3];
5123             break;
5124 
5125 #ifdef ENABLE_CLASSIC
5126         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5127             reverse_bd_addr(&packet[3], addr);
5128             log_info("Create_connection to %s", bd_addr_to_str(addr));
5129 
5130             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5131             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5132                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5133                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5134             }
5135 
5136             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5137             if (!conn) {
5138                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5139                 if (!conn) {
5140                     // notify client that alloc failed
5141                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5142                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5143                 }
5144                 conn->state = SEND_CREATE_CONNECTION;
5145                 conn->role  = HCI_ROLE_MASTER;
5146             }
5147 
5148             conn->con_handle = HCI_CON_HANDLE_INVALID;
5149             conn->role = HCI_ROLE_INVALID;
5150 
5151             log_info("conn state %u", conn->state);
5152             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5153             switch (conn->state) {
5154                 // if connection active exists
5155                 case OPEN:
5156                     // and OPEN, emit connection complete command
5157                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5158                     // packet not sent to controller
5159                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5160                 case RECEIVED_DISCONNECTION_COMPLETE:
5161                     // create connection triggered in disconnect complete event, let's do it now
5162                     break;
5163                 case SEND_CREATE_CONNECTION:
5164                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5165                     break;
5166                 default:
5167                     // otherwise, just ignore as it is already in the open process
5168                     // packet not sent to controller
5169                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5170             }
5171             conn->state = SENT_CREATE_CONNECTION;
5172 
5173             // track outgoing connection
5174             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5175             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5176             break;
5177         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5178             if (hci_stack->link_key_db) {
5179                 reverse_bd_addr(&packet[3], addr);
5180                 hci_stack->link_key_db->delete_link_key(addr);
5181             }
5182             break;
5183 
5184 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5185         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5186             // setup_synchronous_connection? Voice setting at offset 22
5187             // TODO: compare to current setting if sco connection already active
5188             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5189             break;
5190         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5191             // accept_synchronus_connection? Voice setting at offset 18
5192             // TODO: compare to current setting if sco connection already active
5193             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5194             break;
5195 #endif
5196 #endif
5197 
5198 #ifdef ENABLE_BLE
5199         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5200             hci_stack->le_random_address_set = 1;
5201             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5202             break;
5203 #ifdef ENABLE_LE_PERIPHERAL
5204         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5205             hci_stack->le_advertisements_active = packet[3] != 0;
5206             break;
5207 #endif
5208 #ifdef ENABLE_LE_CENTRAL
5209         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5210             // white list used?
5211             initiator_filter_policy = packet[7];
5212             switch (initiator_filter_policy) {
5213                 case 0:
5214                     // whitelist not used
5215                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5216                     break;
5217                 case 1:
5218                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5219                     break;
5220                 default:
5221                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5222                     break;
5223             }
5224             // track outgoing connection
5225             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5226             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5227             break;
5228         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5229             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5230             break;
5231 #endif
5232 #endif
5233         default:
5234             break;
5235     }
5236 
5237     hci_stack->num_cmd_packets--;
5238 
5239     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5240     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5241     if (err != 0){
5242         return ERROR_CODE_HARDWARE_FAILURE;
5243     }
5244     return ERROR_CODE_SUCCESS;
5245 }
5246 
5247 // disconnect because of security block
5248 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5249     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5250     if (!connection) return;
5251     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5252 }
5253 
5254 
5255 // Configure Secure Simple Pairing
5256 
5257 #ifdef ENABLE_CLASSIC
5258 
5259 // enable will enable SSP during init
5260 void gap_ssp_set_enable(int enable){
5261     hci_stack->ssp_enable = enable;
5262 }
5263 
5264 static int hci_local_ssp_activated(void){
5265     return gap_ssp_supported() && hci_stack->ssp_enable;
5266 }
5267 
5268 // if set, BTstack will respond to io capability request using authentication requirement
5269 void gap_ssp_set_io_capability(int io_capability){
5270     hci_stack->ssp_io_capability = io_capability;
5271 }
5272 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5273     hci_stack->ssp_authentication_requirement = authentication_requirement;
5274 }
5275 
5276 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5277 void gap_ssp_set_auto_accept(int auto_accept){
5278     hci_stack->ssp_auto_accept = auto_accept;
5279 }
5280 
5281 void gap_secure_connections_enable(bool enable){
5282     hci_stack->secure_connections_enable = enable;
5283 }
5284 
5285 #endif
5286 
5287 // va_list part of hci_send_cmd
5288 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5289     if (!hci_can_send_command_packet_now()){
5290         log_error("hci_send_cmd called but cannot send packet now");
5291         return ERROR_CODE_COMMAND_DISALLOWED;
5292     }
5293 
5294     // for HCI INITIALIZATION
5295     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5296     hci_stack->last_cmd_opcode = cmd->opcode;
5297 
5298     hci_reserve_packet_buffer();
5299     uint8_t * packet = hci_stack->hci_packet_buffer;
5300     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5301     uint8_t status = hci_send_cmd_packet(packet, size);
5302 
5303     // release packet buffer on error or for synchronous transport implementations
5304     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5305         hci_release_packet_buffer();
5306         hci_emit_transport_packet_sent();
5307     }
5308 
5309     return status;
5310 }
5311 
5312 /**
5313  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5314  */
5315 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5316     va_list argptr;
5317     va_start(argptr, cmd);
5318     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5319     va_end(argptr);
5320     return status;
5321 }
5322 
5323 // Create various non-HCI events.
5324 // TODO: generalize, use table similar to hci_create_command
5325 
5326 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5327     // dump packet
5328     if (dump) {
5329         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5330     }
5331 
5332     // dispatch to all event handlers
5333     btstack_linked_list_iterator_t it;
5334     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5335     while (btstack_linked_list_iterator_has_next(&it)){
5336         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5337         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5338     }
5339 }
5340 
5341 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5342     if (!hci_stack->acl_packet_handler) return;
5343     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5344 }
5345 
5346 #ifdef ENABLE_CLASSIC
5347 static void hci_notify_if_sco_can_send_now(void){
5348     // notify SCO sender if waiting
5349     if (!hci_stack->sco_waiting_for_can_send_now) return;
5350     if (hci_can_send_sco_packet_now()){
5351         hci_stack->sco_waiting_for_can_send_now = 0;
5352         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5353         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5354         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5355     }
5356 }
5357 
5358 // parsing end emitting has been merged to reduce code size
5359 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5360     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5361 
5362     uint8_t * eir_data;
5363     ad_context_t context;
5364     const uint8_t * name;
5365     uint8_t         name_len;
5366 
5367     if (size < 3) return;
5368 
5369     int event_type = hci_event_packet_get_type(packet);
5370     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5371     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5372 
5373     switch (event_type){
5374         case HCI_EVENT_INQUIRY_RESULT:
5375         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5376             if (size != (3 + (num_responses * 14))) return;
5377             break;
5378         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5379             if (size != 257) return;
5380             if (num_responses != 1) return;
5381             break;
5382         default:
5383             return;
5384     }
5385 
5386     // event[1] is set at the end
5387     int i;
5388     for (i=0; i<num_responses;i++){
5389         memset(event, 0, sizeof(event));
5390         event[0] = GAP_EVENT_INQUIRY_RESULT;
5391         uint8_t event_size = 27;    // if name is not set by EIR
5392 
5393         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5394         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5395         (void)memcpy(&event[9],
5396                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5397                      3); // class of device
5398         (void)memcpy(&event[12],
5399                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5400                      2); // clock offset
5401 
5402         switch (event_type){
5403             case HCI_EVENT_INQUIRY_RESULT:
5404                 // 14,15,16,17 = 0, size 18
5405                 break;
5406             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5407                 event[14] = 1;
5408                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5409                 // 16,17 = 0, size 18
5410                 break;
5411             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5412                 event[14] = 1;
5413                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5414                 // EIR packets only contain a single inquiry response
5415                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5416                 name = NULL;
5417                 // Iterate over EIR data
5418                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5419                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5420                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5421                     const uint8_t * data = ad_iterator_get_data(&context);
5422                     // Prefer Complete Local Name over Shortened Local Name
5423                     switch (data_type){
5424                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5425                             if (name) continue;
5426                             /* fall through */
5427                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5428                             name = data;
5429                             name_len = data_size;
5430                             break;
5431                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5432                             if (data_size != 8) break;
5433                             event[16] = 1;
5434                             memcpy(&event[17], data, 8);
5435                             break;
5436                         default:
5437                             break;
5438                     }
5439                 }
5440                 if (name){
5441                     event[25] = 1;
5442                     // truncate name if needed
5443                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5444                     event[26] = len;
5445                     (void)memcpy(&event[27], name, len);
5446                     event_size += len;
5447                 }
5448                 break;
5449             default:
5450                 return;
5451         }
5452         event[1] = event_size - 2;
5453         hci_emit_event(event, event_size, 1);
5454     }
5455 }
5456 #endif
5457 
5458 void hci_emit_state(void){
5459     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5460     uint8_t event[3];
5461     event[0] = BTSTACK_EVENT_STATE;
5462     event[1] = sizeof(event) - 2u;
5463     event[2] = hci_stack->state;
5464     hci_emit_event(event, sizeof(event), 1);
5465 }
5466 
5467 #ifdef ENABLE_CLASSIC
5468 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5469     uint8_t event[13];
5470     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5471     event[1] = sizeof(event) - 2;
5472     event[2] = status;
5473     little_endian_store_16(event, 3, con_handle);
5474     reverse_bd_addr(address, &event[5]);
5475     event[11] = 1; // ACL connection
5476     event[12] = 0; // encryption disabled
5477     hci_emit_event(event, sizeof(event), 1);
5478 }
5479 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5480     if (disable_l2cap_timeouts) return;
5481     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5482     uint8_t event[4];
5483     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5484     event[1] = sizeof(event) - 2;
5485     little_endian_store_16(event, 2, conn->con_handle);
5486     hci_emit_event(event, sizeof(event), 1);
5487 }
5488 #endif
5489 
5490 #ifdef ENABLE_BLE
5491 #ifdef ENABLE_LE_CENTRAL
5492 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){
5493     uint8_t event[21];
5494     event[0] = HCI_EVENT_LE_META;
5495     event[1] = sizeof(event) - 2u;
5496     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5497     event[3] = status;
5498     little_endian_store_16(event, 4, con_handle);
5499     event[6] = 0; // TODO: role
5500     event[7] = address_type;
5501     reverse_bd_addr(address, &event[8]);
5502     little_endian_store_16(event, 14, 0); // interval
5503     little_endian_store_16(event, 16, 0); // latency
5504     little_endian_store_16(event, 18, 0); // supervision timeout
5505     event[20] = 0; // master clock accuracy
5506     hci_emit_event(event, sizeof(event), 1);
5507 }
5508 #endif
5509 #endif
5510 
5511 static void hci_emit_transport_packet_sent(void){
5512     // notify upper stack that it might be possible to send again
5513     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5514     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5515 }
5516 
5517 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5518     uint8_t event[6];
5519     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5520     event[1] = sizeof(event) - 2u;
5521     event[2] = 0; // status = OK
5522     little_endian_store_16(event, 3, con_handle);
5523     event[5] = reason;
5524     hci_emit_event(event, sizeof(event), 1);
5525 }
5526 
5527 static void hci_emit_nr_connections_changed(void){
5528     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5529     uint8_t event[3];
5530     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5531     event[1] = sizeof(event) - 2u;
5532     event[2] = nr_hci_connections();
5533     hci_emit_event(event, sizeof(event), 1);
5534 }
5535 
5536 static void hci_emit_hci_open_failed(void){
5537     log_info("BTSTACK_EVENT_POWERON_FAILED");
5538     uint8_t event[2];
5539     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5540     event[1] = sizeof(event) - 2u;
5541     hci_emit_event(event, sizeof(event), 1);
5542 }
5543 
5544 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5545     log_info("hci_emit_dedicated_bonding_result %u ", status);
5546     uint8_t event[9];
5547     int pos = 0;
5548     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5549     event[pos++] = sizeof(event) - 2u;
5550     event[pos++] = status;
5551     reverse_bd_addr(address, &event[pos]);
5552     hci_emit_event(event, sizeof(event), 1);
5553 }
5554 
5555 
5556 #ifdef ENABLE_CLASSIC
5557 
5558 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5559     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5560     uint8_t event[5];
5561     int pos = 0;
5562     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5563     event[pos++] = sizeof(event) - 2;
5564     little_endian_store_16(event, 2, con_handle);
5565     pos += 2;
5566     event[pos++] = level;
5567     hci_emit_event(event, sizeof(event), 1);
5568 }
5569 
5570 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5571     if (!connection) return LEVEL_0;
5572     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5573     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5574     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5575     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5576     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5577     // LEVEL 4 always requires 128 bit encrytion key size
5578     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5579         security_level = LEVEL_3;
5580     }
5581     return security_level;
5582 }
5583 
5584 static void hci_emit_discoverable_enabled(uint8_t enabled){
5585     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5586     uint8_t event[3];
5587     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5588     event[1] = sizeof(event) - 2;
5589     event[2] = enabled;
5590     hci_emit_event(event, sizeof(event), 1);
5591 }
5592 
5593 // query if remote side supports eSCO
5594 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5595     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5596     if (!connection) return false;
5597     return (connection->remote_supported_features[0] & 1) != 0;
5598 }
5599 
5600 static bool hci_ssp_supported(hci_connection_t * connection){
5601     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5602     return (connection->bonding_flags & mask) == mask;
5603 }
5604 
5605 // query if remote side supports SSP
5606 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5607     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5608     if (!connection) return false;
5609     return hci_ssp_supported(connection) ? 1 : 0;
5610 }
5611 
5612 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5613     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5614 }
5615 
5616 // GAP API
5617 /**
5618  * @bbrief enable/disable bonding. default is enabled
5619  * @praram enabled
5620  */
5621 void gap_set_bondable_mode(int enable){
5622     hci_stack->bondable = enable ? 1 : 0;
5623 }
5624 /**
5625  * @brief Get bondable mode.
5626  * @return 1 if bondable
5627  */
5628 int gap_get_bondable_mode(void){
5629     return hci_stack->bondable;
5630 }
5631 
5632 /**
5633  * @brief map link keys to security levels
5634  */
5635 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5636     switch (link_key_type){
5637         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5638             return LEVEL_4;
5639         case COMBINATION_KEY:
5640         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5641             return LEVEL_3;
5642         default:
5643             return LEVEL_2;
5644     }
5645 }
5646 
5647 /**
5648  * @brief map link keys to secure connection yes/no
5649  */
5650 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5651     switch (link_key_type){
5652         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5653         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5654             return 1;
5655         default:
5656             return 0;
5657     }
5658 }
5659 
5660 /**
5661  * @brief map link keys to authenticated
5662  */
5663 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5664     switch (link_key_type){
5665         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5666         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5667             return 1;
5668         default:
5669             return 0;
5670     }
5671 }
5672 
5673 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5674     log_info("gap_mitm_protection_required_for_security_level %u", level);
5675     return level > LEVEL_2;
5676 }
5677 
5678 /**
5679  * @brief get current security level
5680  */
5681 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5682     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5683     if (!connection) return LEVEL_0;
5684     return gap_security_level_for_connection(connection);
5685 }
5686 
5687 /**
5688  * @brief request connection to device to
5689  * @result GAP_AUTHENTICATION_RESULT
5690  */
5691 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5692     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5693     if (!connection){
5694         hci_emit_security_level(con_handle, LEVEL_0);
5695         return;
5696     }
5697 
5698     btstack_assert(hci_is_le_connection(connection) == false);
5699 
5700     // 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)
5701     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5702     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5703         requested_level = LEVEL_4;
5704     }
5705 
5706     gap_security_level_t current_level = gap_security_level(con_handle);
5707     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5708         requested_level, connection->requested_security_level, current_level);
5709 
5710     // authentication active if authentication request was sent or planned level > 0
5711     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5712     if (authentication_active){
5713         // authentication already active
5714         if (connection->requested_security_level < requested_level){
5715             // increase requested level as new level is higher
5716             // TODO: handle re-authentication when done
5717             connection->requested_security_level = requested_level;
5718         }
5719     } else {
5720         // no request active, notify if security sufficient
5721         if (requested_level <= current_level){
5722             hci_emit_security_level(con_handle, current_level);
5723             return;
5724         }
5725 
5726         // store request
5727         connection->requested_security_level = requested_level;
5728 
5729         // start to authenticate connection
5730         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5731         hci_run();
5732     }
5733 }
5734 
5735 /**
5736  * @brief start dedicated bonding with device. disconnect after bonding
5737  * @param device
5738  * @param request MITM protection
5739  * @result GAP_DEDICATED_BONDING_COMPLETE
5740  */
5741 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5742 
5743     // create connection state machine
5744     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5745 
5746     if (!connection){
5747         return BTSTACK_MEMORY_ALLOC_FAILED;
5748     }
5749 
5750     // delete linkn key
5751     gap_drop_link_key_for_bd_addr(device);
5752 
5753     // configure LEVEL_2/3, dedicated bonding
5754     connection->state = SEND_CREATE_CONNECTION;
5755     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5756     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5757     connection->bonding_flags = BONDING_DEDICATED;
5758 
5759     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5760 
5761     // handle: connnection failure (connection complete != ok)
5762     // handle: authentication failure
5763     // handle: disconnect on done
5764 
5765     hci_run();
5766 
5767     return 0;
5768 }
5769 
5770 void gap_set_local_name(const char * local_name){
5771     hci_stack->local_name = local_name;
5772     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5773     // also update EIR if not set by user
5774     if (hci_stack->eir_data == NULL){
5775         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5776     }
5777     hci_run();
5778 }
5779 #endif
5780 
5781 
5782 #ifdef ENABLE_BLE
5783 
5784 #ifdef ENABLE_LE_CENTRAL
5785 void gap_start_scan(void){
5786     hci_stack->le_scanning_enabled = true;
5787     hci_run();
5788 }
5789 
5790 void gap_stop_scan(void){
5791     hci_stack->le_scanning_enabled = false;
5792     hci_run();
5793 }
5794 
5795 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5796     hci_stack->le_scan_type          = scan_type;
5797     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5798     hci_stack->le_scan_interval      = scan_interval;
5799     hci_stack->le_scan_window        = scan_window;
5800     hci_stack->le_scanning_param_update = true;
5801     hci_run();
5802 }
5803 
5804 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5805     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5806 }
5807 
5808 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5809     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5810     if (!conn){
5811         // disallow if le connection is already outgoing
5812         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5813             log_error("le connection already active");
5814             return ERROR_CODE_COMMAND_DISALLOWED;
5815         }
5816 
5817         log_info("gap_connect: no connection exists yet, creating context");
5818         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5819         if (!conn){
5820             // notify client that alloc failed
5821             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5822             log_info("gap_connect: failed to alloc hci_connection_t");
5823             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5824         }
5825 
5826         // set le connecting state
5827         if (hci_is_le_connection_type(addr_type)){
5828             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5829         }
5830 
5831         conn->state = SEND_CREATE_CONNECTION;
5832         log_info("gap_connect: send create connection next");
5833         hci_run();
5834         return ERROR_CODE_SUCCESS;
5835     }
5836 
5837     if (!hci_is_le_connection(conn) ||
5838         (conn->state == SEND_CREATE_CONNECTION) ||
5839         (conn->state == SENT_CREATE_CONNECTION)) {
5840         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5841         log_error("gap_connect: classic connection or connect is already being created");
5842         return GATT_CLIENT_IN_WRONG_STATE;
5843     }
5844 
5845     // check if connection was just disconnected
5846     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5847         log_info("gap_connect: send create connection (again)");
5848         conn->state = SEND_CREATE_CONNECTION;
5849         hci_run();
5850         return ERROR_CODE_SUCCESS;
5851     }
5852 
5853     log_info("gap_connect: context exists with state %u", conn->state);
5854     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5855     hci_run();
5856     return ERROR_CODE_SUCCESS;
5857 }
5858 
5859 // @assumption: only a single outgoing LE Connection exists
5860 static hci_connection_t * gap_get_outgoing_connection(void){
5861     btstack_linked_item_t *it;
5862     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5863         hci_connection_t * conn = (hci_connection_t *) it;
5864         if (!hci_is_le_connection(conn)) continue;
5865         switch (conn->state){
5866             case SEND_CREATE_CONNECTION:
5867             case SENT_CREATE_CONNECTION:
5868             case SENT_CANCEL_CONNECTION:
5869                 return conn;
5870             default:
5871                 break;
5872         };
5873     }
5874     return NULL;
5875 }
5876 
5877 uint8_t gap_connect_cancel(void){
5878     hci_connection_t * conn = gap_get_outgoing_connection();
5879     if (!conn) return 0;
5880     switch (conn->state){
5881         case SEND_CREATE_CONNECTION:
5882             // skip sending create connection and emit event instead
5883             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5884             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5885             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5886             btstack_memory_hci_connection_free( conn );
5887             break;
5888         case SENT_CREATE_CONNECTION:
5889             // request to send cancel connection
5890             conn->state = SEND_CANCEL_CONNECTION;
5891             hci_run();
5892             break;
5893         default:
5894             break;
5895     }
5896     return 0;
5897 }
5898 #endif
5899 
5900 #ifdef ENABLE_LE_CENTRAL
5901 /**
5902  * @brief Set connection parameters for outgoing connections
5903  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5904  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5905  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5906  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5907  * @param conn_latency, default: 4
5908  * @param supervision_timeout (unit: 10ms), default: 720 ms
5909  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5910  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5911  */
5912 
5913 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5914     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5915     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5916     hci_stack->le_connection_scan_interval = conn_scan_interval;
5917     hci_stack->le_connection_scan_window = conn_scan_window;
5918     hci_stack->le_connection_interval_min = conn_interval_min;
5919     hci_stack->le_connection_interval_max = conn_interval_max;
5920     hci_stack->le_connection_latency = conn_latency;
5921     hci_stack->le_supervision_timeout = supervision_timeout;
5922     hci_stack->le_minimum_ce_length = min_ce_length;
5923     hci_stack->le_maximum_ce_length = max_ce_length;
5924 }
5925 #endif
5926 
5927 /**
5928  * @brief Updates the connection parameters for a given LE connection
5929  * @param handle
5930  * @param conn_interval_min (unit: 1.25ms)
5931  * @param conn_interval_max (unit: 1.25ms)
5932  * @param conn_latency
5933  * @param supervision_timeout (unit: 10ms)
5934  * @returns 0 if ok
5935  */
5936 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5937     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5938     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5939     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5940     connection->le_conn_interval_min = conn_interval_min;
5941     connection->le_conn_interval_max = conn_interval_max;
5942     connection->le_conn_latency = conn_latency;
5943     connection->le_supervision_timeout = supervision_timeout;
5944     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5945     hci_run();
5946     return 0;
5947 }
5948 
5949 /**
5950  * @brief Request an update of the connection parameter for a given LE connection
5951  * @param handle
5952  * @param conn_interval_min (unit: 1.25ms)
5953  * @param conn_interval_max (unit: 1.25ms)
5954  * @param conn_latency
5955  * @param supervision_timeout (unit: 10ms)
5956  * @returns 0 if ok
5957  */
5958 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5959     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5960     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5961     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5962     connection->le_conn_interval_min = conn_interval_min;
5963     connection->le_conn_interval_max = conn_interval_max;
5964     connection->le_conn_latency = conn_latency;
5965     connection->le_supervision_timeout = supervision_timeout;
5966     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5967     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5968     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5969     return 0;
5970 }
5971 
5972 #ifdef ENABLE_LE_PERIPHERAL
5973 
5974 /**
5975  * @brief Set Advertisement Data
5976  * @param advertising_data_length
5977  * @param advertising_data (max 31 octets)
5978  * @note data is not copied, pointer has to stay valid
5979  */
5980 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5981     hci_stack->le_advertisements_data_len = advertising_data_length;
5982     hci_stack->le_advertisements_data = advertising_data;
5983     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5984     hci_run();
5985 }
5986 
5987 /**
5988  * @brief Set Scan Response Data
5989  * @param advertising_data_length
5990  * @param advertising_data (max 31 octets)
5991  * @note data is not copied, pointer has to stay valid
5992  */
5993 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5994     hci_stack->le_scan_response_data_len = scan_response_data_length;
5995     hci_stack->le_scan_response_data = scan_response_data;
5996     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5997     hci_run();
5998 }
5999 
6000 /**
6001  * @brief Set Advertisement Parameters
6002  * @param adv_int_min
6003  * @param adv_int_max
6004  * @param adv_type
6005  * @param direct_address_type
6006  * @param direct_address
6007  * @param channel_map
6008  * @param filter_policy
6009  *
6010  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6011  */
6012  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6013     uint8_t direct_address_typ, bd_addr_t direct_address,
6014     uint8_t channel_map, uint8_t filter_policy) {
6015 
6016     hci_stack->le_advertisements_interval_min = adv_int_min;
6017     hci_stack->le_advertisements_interval_max = adv_int_max;
6018     hci_stack->le_advertisements_type = adv_type;
6019     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6020     hci_stack->le_advertisements_channel_map = channel_map;
6021     hci_stack->le_advertisements_filter_policy = filter_policy;
6022     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6023                  6);
6024 
6025     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6026     hci_run();
6027  }
6028 
6029 /**
6030  * @brief Enable/Disable Advertisements
6031  * @param enabled
6032  */
6033 void gap_advertisements_enable(int enabled){
6034     hci_stack->le_advertisements_enabled = enabled != 0;
6035     hci_update_advertisements_enabled_for_current_roles();
6036     hci_run();
6037 }
6038 
6039 #endif
6040 
6041 void hci_le_set_own_address_type(uint8_t own_address_type){
6042     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6043     if (own_address_type == hci_stack->le_own_addr_type) return;
6044     hci_stack->le_own_addr_type = own_address_type;
6045 
6046 #ifdef ENABLE_LE_PERIPHERAL
6047     // update advertisement parameters, too
6048     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6049     hci_run();
6050 #endif
6051 #ifdef ENABLE_LE_CENTRAL
6052     // note: we don't update scan parameters or modify ongoing connection attempts
6053 #endif
6054 }
6055 
6056 #endif
6057 
6058 uint8_t gap_disconnect(hci_con_handle_t handle){
6059     hci_connection_t * conn = hci_connection_for_handle(handle);
6060     if (!conn){
6061         hci_emit_disconnection_complete(handle, 0);
6062         return 0;
6063     }
6064     // ignore if already disconnected
6065     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6066         return 0;
6067     }
6068     conn->state = SEND_DISCONNECT;
6069     hci_run();
6070     return 0;
6071 }
6072 
6073 int gap_read_rssi(hci_con_handle_t con_handle){
6074     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6075     if (hci_connection == NULL) return 0;
6076     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6077     hci_run();
6078     return 1;
6079 }
6080 
6081 /**
6082  * @brief Get connection type
6083  * @param con_handle
6084  * @result connection_type
6085  */
6086 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6087     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6088     if (!conn) return GAP_CONNECTION_INVALID;
6089     switch (conn->address_type){
6090         case BD_ADDR_TYPE_LE_PUBLIC:
6091         case BD_ADDR_TYPE_LE_RANDOM:
6092             return GAP_CONNECTION_LE;
6093         case BD_ADDR_TYPE_SCO:
6094             return GAP_CONNECTION_SCO;
6095         case BD_ADDR_TYPE_ACL:
6096             return GAP_CONNECTION_ACL;
6097         default:
6098             return GAP_CONNECTION_INVALID;
6099     }
6100 }
6101 
6102 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6103     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6104     if (!conn) return HCI_ROLE_INVALID;
6105     return (hci_role_t) conn->role;
6106 }
6107 
6108 
6109 #ifdef ENABLE_CLASSIC
6110 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6111     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6112     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6113     conn->request_role = role;
6114     hci_run();
6115     return ERROR_CODE_SUCCESS;
6116 }
6117 #endif
6118 
6119 #ifdef ENABLE_BLE
6120 
6121 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){
6122     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6123     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6124 
6125     conn->le_phy_update_all_phys    = all_phys;
6126     conn->le_phy_update_tx_phys     = tx_phys;
6127     conn->le_phy_update_rx_phys     = rx_phys;
6128     conn->le_phy_update_phy_options = phy_options;
6129 
6130     hci_run();
6131 
6132     return 0;
6133 }
6134 
6135 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6136     // check if already in list
6137     btstack_linked_list_iterator_t it;
6138     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6139     while (btstack_linked_list_iterator_has_next(&it)) {
6140         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6141         if (entry->address_type != address_type) {
6142             continue;
6143         }
6144         if (memcmp(entry->address, address, 6) != 0) {
6145             continue;
6146         }
6147 		// disallow if already scheduled to add
6148 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6149 			return ERROR_CODE_COMMAND_DISALLOWED;
6150 		}
6151 		// still on controller, but scheduled to remove -> re-add
6152 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6153 		return ERROR_CODE_SUCCESS;
6154     }
6155     // alloc and add to list
6156     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6157     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6158     entry->address_type = address_type;
6159     (void)memcpy(entry->address, address, 6);
6160     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6161     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6162     return ERROR_CODE_SUCCESS;
6163 }
6164 
6165 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6166     btstack_linked_list_iterator_t it;
6167     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6168     while (btstack_linked_list_iterator_has_next(&it)){
6169         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6170         if (entry->address_type != address_type) {
6171             continue;
6172         }
6173         if (memcmp(entry->address, address, 6) != 0) {
6174             continue;
6175         }
6176         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6177             // remove from controller if already present
6178             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6179         }  else {
6180             // directly remove entry from whitelist
6181             btstack_linked_list_iterator_remove(&it);
6182             btstack_memory_whitelist_entry_free(entry);
6183         }
6184         return ERROR_CODE_SUCCESS;
6185     }
6186     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6187 }
6188 
6189 static void hci_whitelist_clear(void){
6190     btstack_linked_list_iterator_t it;
6191     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6192     while (btstack_linked_list_iterator_has_next(&it)){
6193         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6194         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6195             // remove from controller if already present
6196             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6197             continue;
6198         }
6199         // directly remove entry from whitelist
6200         btstack_linked_list_iterator_remove(&it);
6201         btstack_memory_whitelist_entry_free(entry);
6202     }
6203 }
6204 
6205 /**
6206  * @brief Clear Whitelist
6207  * @returns 0 if ok
6208  */
6209 uint8_t gap_whitelist_clear(void){
6210     hci_whitelist_clear();
6211     hci_run();
6212     return ERROR_CODE_SUCCESS;
6213 }
6214 
6215 /**
6216  * @brief Add Device to Whitelist
6217  * @param address_typ
6218  * @param address
6219  * @returns 0 if ok
6220  */
6221 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6222     uint8_t status = hci_whitelist_add(address_type, address);
6223     if (status){
6224         return status;
6225     }
6226     hci_run();
6227     return ERROR_CODE_SUCCESS;
6228 }
6229 
6230 /**
6231  * @brief Remove Device from Whitelist
6232  * @param address_typ
6233  * @param address
6234  * @returns 0 if ok
6235  */
6236 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6237     uint8_t status = hci_whitelist_remove(address_type, address);
6238     if (status){
6239         return status;
6240     }
6241     hci_run();
6242     return ERROR_CODE_SUCCESS;
6243 }
6244 
6245 #ifdef ENABLE_LE_CENTRAL
6246 /**
6247  *  @brief Connect with Whitelist
6248  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6249  *  @returns - if ok
6250  */
6251 uint8_t gap_connect_with_whitelist(void){
6252     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6253         return ERROR_CODE_COMMAND_DISALLOWED;
6254     }
6255     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6256     hci_run();
6257     return ERROR_CODE_SUCCESS;
6258 }
6259 
6260 /**
6261  * @brief Auto Connection Establishment - Start Connecting to device
6262  * @param address_typ
6263  * @param address
6264  * @returns 0 if ok
6265  */
6266 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6267     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6268         return ERROR_CODE_COMMAND_DISALLOWED;
6269     }
6270 
6271     uint8_t status = hci_whitelist_add(address_type, address);
6272     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6273         return status;
6274     }
6275 
6276     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6277 
6278     hci_run();
6279     return ERROR_CODE_SUCCESS;
6280 }
6281 
6282 /**
6283  * @brief Auto Connection Establishment - Stop Connecting to device
6284  * @param address_typ
6285  * @param address
6286  * @returns 0 if ok
6287  */
6288 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6289     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6290         return ERROR_CODE_COMMAND_DISALLOWED;
6291     }
6292 
6293     hci_whitelist_remove(address_type, address);
6294     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6295         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6296     }
6297     hci_run();
6298     return 0;
6299 }
6300 
6301 /**
6302  * @brief Auto Connection Establishment - Stop everything
6303  * @note  Convenience function to stop all active auto connection attempts
6304  */
6305 uint8_t gap_auto_connection_stop_all(void){
6306     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6307         return ERROR_CODE_COMMAND_DISALLOWED;
6308     }
6309     hci_whitelist_clear();
6310     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6311     hci_run();
6312     return ERROR_CODE_SUCCESS;
6313 }
6314 
6315 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6316     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6317     if (!conn) return 0;
6318     return conn->le_connection_interval;
6319 }
6320 #endif
6321 #endif
6322 
6323 #ifdef ENABLE_CLASSIC
6324 /**
6325  * @brief Set Extended Inquiry Response data
6326  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6327  * @note has to be done before stack starts up
6328  */
6329 void gap_set_extended_inquiry_response(const uint8_t * data){
6330     hci_stack->eir_data = data;
6331     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6332     hci_run();
6333 }
6334 
6335 /**
6336  * @brief Start GAP Classic Inquiry
6337  * @param duration in 1.28s units
6338  * @return 0 if ok
6339  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6340  */
6341 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6342     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6343     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6344     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6345         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6346     }
6347     hci_stack->inquiry_state = duration_in_1280ms_units;
6348     hci_run();
6349     return 0;
6350 }
6351 
6352 /**
6353  * @brief Stop GAP Classic Inquiry
6354  * @returns 0 if ok
6355  */
6356 int gap_inquiry_stop(void){
6357     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6358         // emit inquiry complete event, before it even started
6359         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6360         hci_emit_event(event, sizeof(event), 1);
6361         return 0;
6362     }
6363     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6364     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6365     hci_run();
6366     return 0;
6367 }
6368 
6369 void gap_inquiry_set_lap(uint32_t lap){
6370     hci_stack->inquiry_lap = lap;
6371 }
6372 
6373 
6374 /**
6375  * @brief Remote Name Request
6376  * @param addr
6377  * @param page_scan_repetition_mode
6378  * @param clock_offset only used when bit 15 is set
6379  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6380  */
6381 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6382     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6383     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6384     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6385     hci_stack->remote_name_clock_offset = clock_offset;
6386     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6387     hci_run();
6388     return 0;
6389 }
6390 
6391 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6392     hci_stack->gap_pairing_state = state;
6393     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6394     hci_run();
6395     return 0;
6396 }
6397 
6398 /**
6399  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6400  * @param addr
6401  * @param pin_data
6402  * @param pin_len
6403  * @return 0 if ok
6404  */
6405 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6406     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6407     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6408     hci_stack->gap_pairing_pin_len = pin_len;
6409     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6410 }
6411 
6412 /**
6413  * @brief Legacy Pairing Pin Code Response
6414  * @param addr
6415  * @param pin
6416  * @return 0 if ok
6417  */
6418 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6419     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6420 }
6421 
6422 /**
6423  * @brief Abort Legacy Pairing
6424  * @param addr
6425  * @param pin
6426  * @return 0 if ok
6427  */
6428 int gap_pin_code_negative(bd_addr_t addr){
6429     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6430     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6431 }
6432 
6433 /**
6434  * @brief SSP Passkey Response
6435  * @param addr
6436  * @param passkey
6437  * @return 0 if ok
6438  */
6439 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6440     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6441     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6442     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6443 }
6444 
6445 /**
6446  * @brief Abort SSP Passkey Entry/Pairing
6447  * @param addr
6448  * @param pin
6449  * @return 0 if ok
6450  */
6451 int gap_ssp_passkey_negative(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_PASSKEY_NEGATIVE);
6454 }
6455 
6456 /**
6457  * @brief Accept SSP Numeric Comparison
6458  * @param addr
6459  * @param passkey
6460  * @return 0 if ok
6461  */
6462 int gap_ssp_confirmation_response(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);
6465 }
6466 
6467 /**
6468  * @brief Abort SSP Numeric Comparison/Pairing
6469  * @param addr
6470  * @param pin
6471  * @return 0 if ok
6472  */
6473 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6474     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6475     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6476 }
6477 
6478 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6479 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6480     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6481     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6482     connectionSetAuthenticationFlags(conn, flag);
6483     hci_run();
6484     return ERROR_CODE_SUCCESS;
6485 }
6486 #endif
6487 
6488 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6489 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6490     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6491 }
6492 
6493 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6494     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6495 }
6496 #endif
6497 
6498 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6499 /**
6500  * @brief Report Remote OOB Data
6501  * @param bd_addr
6502  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6503  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6504  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6505  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6506  */
6507 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){
6508     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6509     if (connection == NULL) {
6510         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6511     }
6512     connection->classic_oob_c_192 = c_192;
6513     connection->classic_oob_r_192 = r_192;
6514 
6515     // ignore P-256 if not supported by us
6516     if (hci_stack->secure_connections_active){
6517         connection->classic_oob_c_256 = c_256;
6518         connection->classic_oob_r_256 = r_256;
6519     }
6520 
6521     return ERROR_CODE_SUCCESS;
6522 }
6523 /**
6524  * @brief Generate new OOB data
6525  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6526  */
6527 void gap_ssp_generate_oob_data(void){
6528     hci_stack->classic_read_local_oob_data = true;
6529     hci_run();
6530 }
6531 
6532 #endif
6533 
6534 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6535 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6536     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6537     if (connection == NULL) {
6538         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6539     }
6540 
6541     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6542     connection->link_key_type = type;
6543 
6544     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6545 }
6546 
6547 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6548 /**
6549  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6550  * @param inquiry_mode see bluetooth_defines.h
6551  */
6552 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6553     hci_stack->inquiry_mode = inquiry_mode;
6554 }
6555 
6556 /**
6557  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6558  */
6559 void hci_set_sco_voice_setting(uint16_t voice_setting){
6560     hci_stack->sco_voice_setting = voice_setting;
6561 }
6562 
6563 /**
6564  * @brief Get SCO Voice Setting
6565  * @return current voice setting
6566  */
6567 uint16_t hci_get_sco_voice_setting(void){
6568     return hci_stack->sco_voice_setting;
6569 }
6570 
6571 static int hci_have_usb_transport(void){
6572     if (!hci_stack->hci_transport) return 0;
6573     const char * transport_name = hci_stack->hci_transport->name;
6574     if (!transport_name) return 0;
6575     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6576 }
6577 
6578 /** @brief Get SCO packet length for current SCO Voice setting
6579  *  @note  Using SCO packets of the exact length is required for USB transfer
6580  *  @return Length of SCO packets in bytes (not audio frames)
6581  */
6582 uint16_t hci_get_sco_packet_length(void){
6583     uint16_t sco_packet_length = 0;
6584 
6585 #ifdef ENABLE_SCO_OVER_HCI
6586     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6587     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6588 
6589     if (hci_have_usb_transport()){
6590         // see Core Spec for H2 USB Transfer.
6591         // 3 byte SCO header + 24 bytes per connection
6592         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6593         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6594     } else {
6595         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6596         sco_packet_length = 3 + 60 * multiplier;
6597         // assert that it still fits inside an SCO buffer
6598         if (sco_packet_length > hci_stack->sco_data_packet_length){
6599             sco_packet_length = 3 + 60;
6600         }
6601     }
6602 #endif
6603 
6604 #ifdef HAVE_SCO_TRANSPORT
6605     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6606     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6607     sco_packet_length = 3 + 60 * multiplier;
6608 #endif
6609     return sco_packet_length;
6610 }
6611 
6612 /**
6613 * @brief Sets the master/slave policy
6614 * @param policy (0: attempt to become master, 1: let connecting device decide)
6615 */
6616 void hci_set_master_slave_policy(uint8_t policy){
6617     hci_stack->master_slave_policy = policy;
6618 }
6619 
6620 #endif
6621 
6622 HCI_STATE hci_get_state(void){
6623     return hci_stack->state;
6624 }
6625 
6626 #ifdef ENABLE_CLASSIC
6627 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6628     hci_stack->gap_classic_accept_callback = accept_callback;
6629 }
6630 #endif
6631 
6632 /**
6633  * @brief Set callback for Bluetooth Hardware Error
6634  */
6635 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6636     hci_stack->hardware_error_callback = fn;
6637 }
6638 
6639 void hci_disconnect_all(void){
6640     btstack_linked_list_iterator_t it;
6641     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6642     while (btstack_linked_list_iterator_has_next(&it)){
6643         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6644         if (con->state == SENT_DISCONNECT) continue;
6645         con->state = SEND_DISCONNECT;
6646     }
6647     hci_run();
6648 }
6649 
6650 uint16_t hci_get_manufacturer(void){
6651     return hci_stack->manufacturer;
6652 }
6653 
6654 #ifdef ENABLE_BLE
6655 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6656     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6657     if (!hci_con) return NULL;
6658     return &hci_con->sm_connection;
6659 }
6660 
6661 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6662 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6663 #endif
6664 
6665 int gap_encryption_key_size(hci_con_handle_t con_handle){
6666     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6667     if (hci_connection == NULL) return 0;
6668     if (hci_is_le_connection(hci_connection)){
6669 #ifdef ENABLE_BLE
6670         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6671         if (sm_conn->sm_connection_encrypted) {
6672             return sm_conn->sm_actual_encryption_key_size;
6673         }
6674 #endif
6675     } else {
6676 #ifdef ENABLE_CLASSIC
6677         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6678             return hci_connection->encryption_key_size;
6679         }
6680 #endif
6681     }
6682     return 0;
6683 }
6684 
6685 int gap_authenticated(hci_con_handle_t con_handle){
6686     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6687     if (hci_connection == NULL) return 0;
6688 
6689     switch (hci_connection->address_type){
6690 #ifdef ENABLE_BLE
6691         case BD_ADDR_TYPE_LE_PUBLIC:
6692         case BD_ADDR_TYPE_LE_RANDOM:
6693             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6694             return hci_connection->sm_connection.sm_connection_authenticated;
6695 #endif
6696 #ifdef ENABLE_CLASSIC
6697         case BD_ADDR_TYPE_SCO:
6698         case BD_ADDR_TYPE_ACL:
6699             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6700 #endif
6701         default:
6702             return 0;
6703     }
6704 }
6705 
6706 int gap_secure_connection(hci_con_handle_t con_handle){
6707     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6708     if (hci_connection == NULL) return 0;
6709 
6710     switch (hci_connection->address_type){
6711 #ifdef ENABLE_BLE
6712         case BD_ADDR_TYPE_LE_PUBLIC:
6713         case BD_ADDR_TYPE_LE_RANDOM:
6714             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6715             return hci_connection->sm_connection.sm_connection_sc;
6716 #endif
6717 #ifdef ENABLE_CLASSIC
6718         case BD_ADDR_TYPE_SCO:
6719         case BD_ADDR_TYPE_ACL:
6720             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6721 #endif
6722         default:
6723             return 0;
6724     }
6725 }
6726 
6727 bool gap_bonded(hci_con_handle_t con_handle){
6728 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6729 	if (hci_connection == NULL) return 0;
6730 
6731 #ifdef ENABLE_CLASSIC
6732 	link_key_t link_key;
6733 	link_key_type_t link_key_type;
6734 #endif
6735 	switch (hci_connection->address_type){
6736 #ifdef ENABLE_BLE
6737 		case BD_ADDR_TYPE_LE_PUBLIC:
6738 		case BD_ADDR_TYPE_LE_RANDOM:
6739 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6740 #endif
6741 #ifdef ENABLE_CLASSIC
6742 		case BD_ADDR_TYPE_SCO:
6743 		case BD_ADDR_TYPE_ACL:
6744 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6745 #endif
6746 		default:
6747 			return false;
6748 	}
6749 }
6750 
6751 #ifdef ENABLE_BLE
6752 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6753     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6754     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6755     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6756     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6757     return sm_conn->sm_connection_authorization_state;
6758 }
6759 #endif
6760 
6761 #ifdef ENABLE_CLASSIC
6762 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){
6763     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6764     if (!conn) return GAP_CONNECTION_INVALID;
6765     conn->sniff_min_interval = sniff_min_interval;
6766     conn->sniff_max_interval = sniff_max_interval;
6767     conn->sniff_attempt = sniff_attempt;
6768     conn->sniff_timeout = sniff_timeout;
6769     hci_run();
6770     return 0;
6771 }
6772 
6773 /**
6774  * @brief Exit Sniff mode
6775  * @param con_handle
6776  @ @return 0 if ok
6777  */
6778 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6779     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6780     if (!conn) return GAP_CONNECTION_INVALID;
6781     conn->sniff_min_interval = 0xffff;
6782     hci_run();
6783     return 0;
6784 }
6785 
6786 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){
6787     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6788     if (!conn) return GAP_CONNECTION_INVALID;
6789     conn->sniff_subrating_max_latency = max_latency;
6790     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6791     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6792     hci_run();
6793     return ERROR_CODE_SUCCESS;
6794 }
6795 
6796 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){
6797     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6798     if (!conn) return GAP_CONNECTION_INVALID;
6799     conn->qos_service_type = service_type;
6800     conn->qos_token_rate = token_rate;
6801     conn->qos_peak_bandwidth = peak_bandwidth;
6802     conn->qos_latency = latency;
6803     conn->qos_delay_variation = delay_variation;
6804     hci_run();
6805     return ERROR_CODE_SUCCESS;
6806 }
6807 
6808 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6809     hci_stack->new_page_scan_interval = page_scan_interval;
6810     hci_stack->new_page_scan_window = page_scan_window;
6811     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_ACTIVITY;
6812     hci_run();
6813 }
6814 
6815 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6816     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6817     hci_stack->gap_tasks |= GAP_TASK_WRITE_PAGE_SCAN_TYPE;
6818     hci_run();
6819 }
6820 
6821 #endif
6822 
6823 void hci_halting_defer(void){
6824     if (hci_stack->state != HCI_STATE_HALTING) return;
6825     switch (hci_stack->substate){
6826         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6827         case HCI_HALTING_CLOSE:
6828             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6829             break;
6830         default:
6831             break;
6832     }
6833 }
6834 
6835 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6836 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6837     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6838     if (le_device_db_index >= le_device_db_max_count()) return;
6839     uint8_t offset = le_device_db_index >> 3;
6840     uint8_t mask = 1 << (le_device_db_index & 7);
6841     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6842     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6843     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6844         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6845     }
6846 }
6847 
6848 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6849 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6850 	if (le_device_db_index >= le_device_db_max_count()) return;
6851 	uint8_t offset = le_device_db_index >> 3;
6852 	uint8_t mask = 1 << (le_device_db_index & 7);
6853 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6854 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6855 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6856 	}
6857 }
6858 
6859 uint8_t gap_load_resolving_list_from_le_device_db(void){
6860 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6861 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6862 	}
6863 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6864 		// restart le resolving list update
6865 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6866 	}
6867 	return ERROR_CODE_SUCCESS;
6868 }
6869 #endif
6870 
6871 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6872 void hci_setup_test_connections_fuzz(void){
6873     hci_connection_t * conn;
6874 
6875     // default address: 66:55:44:33:00:01
6876     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6877 
6878     // setup Controller info
6879     hci_stack->num_cmd_packets = 255;
6880     hci_stack->acl_packets_total_num = 255;
6881 
6882     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6883     addr[5] = 0x01;
6884     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6885     conn->con_handle = addr[5];
6886     conn->role  = HCI_ROLE_SLAVE;
6887     conn->state = RECEIVED_CONNECTION_REQUEST;
6888     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6889 
6890     // setup incoming Classic SCO connection with con handle 0x0002
6891     addr[5] = 0x02;
6892     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6893     conn->con_handle = addr[5];
6894     conn->role  = HCI_ROLE_SLAVE;
6895     conn->state = RECEIVED_CONNECTION_REQUEST;
6896     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6897 
6898     // setup ready Classic ACL connection with con handle 0x0003
6899     addr[5] = 0x03;
6900     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6901     conn->con_handle = addr[5];
6902     conn->role  = HCI_ROLE_SLAVE;
6903     conn->state = OPEN;
6904     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6905 
6906     // setup ready Classic SCO connection with con handle 0x0004
6907     addr[5] = 0x04;
6908     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6909     conn->con_handle = addr[5];
6910     conn->role  = HCI_ROLE_SLAVE;
6911     conn->state = OPEN;
6912     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6913 
6914     // setup ready LE ACL connection with con handle 0x005 and public address
6915     addr[5] = 0x05;
6916     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6917     conn->con_handle = addr[5];
6918     conn->role  = HCI_ROLE_SLAVE;
6919     conn->state = OPEN;
6920     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6921     conn->sm_connection.sm_connection_encrypted = 1;
6922 }
6923 
6924 void hci_free_connections_fuzz(void){
6925     btstack_linked_list_iterator_t it;
6926     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6927     while (btstack_linked_list_iterator_has_next(&it)){
6928         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6929         btstack_linked_list_iterator_remove(&it);
6930         btstack_memory_hci_connection_free(con);
6931     }
6932 }
6933 void hci_simulate_working_fuzz(void){
6934     hci_init_done();
6935     hci_stack->num_cmd_packets = 255;
6936 }
6937 #endif
6938