xref: /btstack/src/hci.c (revision bc2dcc035309406641c216abfbef0f326c129819)
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 #endif
1317 
1318 #ifndef HAVE_HOST_CONTROLLER_API
1319 
1320 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1321     if (!hci_stack->config) return 0;
1322     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1323     // Limit baud rate for Broadcom chipsets to 3 mbps
1324     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1325         baud_rate = 3000000;
1326     }
1327     return baud_rate;
1328 }
1329 
1330 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1331     UNUSED(ds);
1332 
1333     switch (hci_stack->substate){
1334         case HCI_INIT_W4_SEND_RESET:
1335             log_info("Resend HCI Reset");
1336             hci_stack->substate = HCI_INIT_SEND_RESET;
1337             hci_stack->num_cmd_packets = 1;
1338             hci_run();
1339             break;
1340         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1341             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1342             if (hci_stack->hci_transport->reset_link){
1343                 hci_stack->hci_transport->reset_link();
1344             }
1345 
1346             /* fall through */
1347 
1348         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1349             log_info("Resend HCI Reset - CSR Warm Boot");
1350             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1351             hci_stack->num_cmd_packets = 1;
1352             hci_run();
1353             break;
1354         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1355             if (hci_stack->hci_transport->set_baudrate){
1356                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1357                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1358                 hci_stack->hci_transport->set_baudrate(baud_rate);
1359             }
1360             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1361             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1362                 if (hci_stack->hci_transport->reset_link){
1363                     log_info("Link Reset");
1364                     hci_stack->hci_transport->reset_link();
1365                 }
1366                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1367                 hci_run();
1368             }
1369             break;
1370         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1371             // otherwise continue
1372             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1373             hci_send_cmd(&hci_read_local_supported_commands);
1374             break;
1375         default:
1376             break;
1377     }
1378 }
1379 #endif
1380 
1381 static void hci_initializing_next_state(void){
1382     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1383 }
1384 
1385 // assumption: hci_can_send_command_packet_now() == true
1386 static void hci_initializing_run(void){
1387     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1388     switch (hci_stack->substate){
1389         case HCI_INIT_SEND_RESET:
1390             hci_state_reset();
1391 
1392 #ifndef HAVE_HOST_CONTROLLER_API
1393             // prepare reset if command complete not received in 100ms
1394             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1395             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1396             btstack_run_loop_add_timer(&hci_stack->timeout);
1397 #endif
1398             // send command
1399             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1400             hci_send_cmd(&hci_reset);
1401             break;
1402         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1403             hci_send_cmd(&hci_read_local_version_information);
1404             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1405             break;
1406         case HCI_INIT_SEND_READ_LOCAL_NAME:
1407             hci_send_cmd(&hci_read_local_name);
1408             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1409             break;
1410 
1411 #ifndef HAVE_HOST_CONTROLLER_API
1412         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1413             hci_state_reset();
1414             // prepare reset if command complete not received in 100ms
1415             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1416             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1417             btstack_run_loop_add_timer(&hci_stack->timeout);
1418             // send command
1419             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1420             hci_send_cmd(&hci_reset);
1421             break;
1422         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1423             hci_state_reset();
1424             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1425             hci_send_cmd(&hci_reset);
1426             break;
1427         case HCI_INIT_SEND_BAUD_CHANGE: {
1428             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1429             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1430             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1431             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1432             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1433             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1434             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1435             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1436                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1437                 btstack_run_loop_add_timer(&hci_stack->timeout);
1438             }
1439             break;
1440         }
1441         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1442             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1443             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1444             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1445             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1446             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1447             break;
1448         }
1449         case HCI_INIT_CUSTOM_INIT:
1450             // Custom initialization
1451             if (hci_stack->chipset && hci_stack->chipset->next_command){
1452                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1453                 bool send_cmd = false;
1454                 switch (hci_stack->chipset_result){
1455                     case BTSTACK_CHIPSET_VALID_COMMAND:
1456                         send_cmd = true;
1457                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1458                         break;
1459                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1460                         send_cmd = true;
1461                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1462                         log_info("CSR Warm Boot");
1463                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1464                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1465                         btstack_run_loop_add_timer(&hci_stack->timeout);
1466                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1467                             && hci_stack->config
1468                             && hci_stack->chipset
1469                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1470                             && hci_stack->hci_transport->set_baudrate
1471                             && hci_transport_uart_get_main_baud_rate()){
1472                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1473                         } else {
1474                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1475                         }
1476                         break;
1477                     default:
1478                         break;
1479                 }
1480 
1481                 if (send_cmd){
1482                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1483                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1484                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1485                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1486                     break;
1487                 }
1488                 log_info("Init script done");
1489 
1490                 // Init script download on Broadcom chipsets causes:
1491                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1492                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1493                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1494 
1495                     // - baud rate to reset, restore UART baud rate if needed
1496                     int need_baud_change = hci_stack->config
1497                         && hci_stack->chipset
1498                         && hci_stack->chipset->set_baudrate_command
1499                         && hci_stack->hci_transport->set_baudrate
1500                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1501                     if (need_baud_change) {
1502                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1503                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1504                         hci_stack->hci_transport->set_baudrate(baud_rate);
1505                     }
1506 
1507                     uint16_t bcm_delay_ms = 300;
1508                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1509                     //   -> Work around: wait here.
1510                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1511                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1512                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1513                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1514                     btstack_run_loop_add_timer(&hci_stack->timeout);
1515                     break;
1516                 }
1517             }
1518             // otherwise continue
1519             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1520             hci_send_cmd(&hci_read_local_supported_commands);
1521             break;
1522         case HCI_INIT_SET_BD_ADDR:
1523             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1524             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1525             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1526             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1527             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1528             break;
1529 #endif
1530 
1531         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1532             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1533             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1534             hci_send_cmd(&hci_read_local_supported_commands);
1535             break;
1536         case HCI_INIT_READ_BD_ADDR:
1537             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1538             hci_send_cmd(&hci_read_bd_addr);
1539             break;
1540         case HCI_INIT_READ_BUFFER_SIZE:
1541             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1542             hci_send_cmd(&hci_read_buffer_size);
1543             break;
1544         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1545             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1546             hci_send_cmd(&hci_read_local_supported_features);
1547             break;
1548 
1549 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1550         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1551             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1552             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1553             break;
1554         case HCI_INIT_HOST_BUFFER_SIZE:
1555             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1556             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1557                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1558             break;
1559 #endif
1560 
1561         case HCI_INIT_SET_EVENT_MASK:
1562             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1563             if (hci_le_supported()){
1564                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x3FFFFFFFU);
1565             } else {
1566                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1567                 hci_send_cmd(&hci_set_event_mask,0xFFFFFFFFU, 0x1FFFFFFFU);
1568             }
1569             break;
1570 
1571 #ifdef ENABLE_CLASSIC
1572         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1573             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1574             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1575             break;
1576         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1577             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1578             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1579             break;
1580         case HCI_INIT_WRITE_INQUIRY_MODE:
1581             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1582             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1583             break;
1584         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1585             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1586 			hci_stack->secure_connections_active = true;
1587             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1588             break;
1589         // only sent if ENABLE_SCO_OVER_HCI is defined
1590         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1591             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1592             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1593             break;
1594         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1595             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1596             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1597             break;
1598         // only sent if manufacturer is Broadcom and ENABLE_SCO_OVER_HCI or ENABLE_SCO_OVER_PCM is defined
1599         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1600             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1601 #ifdef ENABLE_SCO_OVER_HCI
1602             log_info("BCM: Route SCO data via HCI transport");
1603             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1604 #endif
1605 #ifdef ENABLE_SCO_OVER_PCM
1606             log_info("BCM: Route SCO data via PCM interface");
1607 #ifdef ENABLE_BCM_PCM_WBS
1608             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1609             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 2, 0, 1, 1);
1610 #else
1611             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1612             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 0, 1, 0, 1, 1);
1613 #endif
1614 #endif
1615             break;
1616 #ifdef ENABLE_SCO_OVER_PCM
1617         case HCI_INIT_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1618             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1619             log_info("BCM: Config PCM interface for I2S");
1620 #ifdef ENABLE_BCM_PCM_WBS
1621             // 512 kHz bit clock for 2 channels x 16 bit x 8 kHz
1622             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 2);
1623 #else
1624             // 256 kHz bit clock for 2 channels x 16 bit x 8 kHz
1625             hci_send_cmd(&hci_bcm_write_i2spcm_interface_param, 1, 1, 0, 1);
1626 #endif
1627             break;
1628 #endif
1629 #endif
1630 
1631 #ifdef ENABLE_BLE
1632         // LE INIT
1633         case HCI_INIT_LE_READ_BUFFER_SIZE:
1634             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1635             hci_send_cmd(&hci_le_read_buffer_size);
1636             break;
1637         case HCI_INIT_LE_SET_EVENT_MASK:
1638             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1639             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1640             break;
1641         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1642             // LE Supported Host = 1, Simultaneous Host = 0
1643             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1644             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1645             break;
1646 #endif
1647 
1648 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1649         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1650             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1651             hci_send_cmd(&hci_le_read_maximum_data_length);
1652             break;
1653         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1654             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1655             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1656             break;
1657 #endif
1658 
1659 #ifdef ENABLE_LE_CENTRAL
1660         case HCI_INIT_READ_WHITE_LIST_SIZE:
1661             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1662             hci_send_cmd(&hci_le_read_white_list_size);
1663             break;
1664         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1665             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1666             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);
1667             break;
1668 #endif
1669         default:
1670             return;
1671     }
1672 }
1673 
1674 static void hci_init_done(void){
1675     // done. tell the app
1676     log_info("hci_init_done -> HCI_STATE_WORKING");
1677     hci_stack->state = HCI_STATE_WORKING;
1678     hci_emit_state();
1679     hci_run();
1680 }
1681 
1682 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1683     bool command_completed = false;
1684     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1685         uint16_t opcode = little_endian_read_16(packet,3);
1686         if (opcode == hci_stack->last_cmd_opcode){
1687             command_completed = true;
1688             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1689         } else {
1690             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1691         }
1692     }
1693 
1694     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1695         uint8_t  status = packet[2];
1696         uint16_t opcode = little_endian_read_16(packet,4);
1697         if (opcode == hci_stack->last_cmd_opcode){
1698             if (status){
1699                 command_completed = true;
1700                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1701             } else {
1702                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1703             }
1704         } else {
1705             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1706         }
1707     }
1708 #ifndef HAVE_HOST_CONTROLLER_API
1709     // Vendor == CSR
1710     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1711         // TODO: track actual command
1712         command_completed = true;
1713     }
1714 
1715     // Vendor == Toshiba
1716     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1717         // TODO: track actual command
1718         command_completed = true;
1719         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1720         hci_stack->num_cmd_packets = 1;
1721     }
1722 #endif
1723 
1724     return command_completed;
1725 }
1726 
1727 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1728 
1729     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1730 
1731     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1732 
1733 #ifndef HAVE_HOST_CONTROLLER_API
1734 
1735     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1736     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1737     //
1738     // HCI Reset
1739     // Timeout 100 ms
1740     // HCI Reset
1741     // Command Complete Reset
1742     // HCI Read Local Version Information
1743     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1744     // hang...
1745     //
1746     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1747     if (!command_completed
1748             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1749             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1750 
1751         uint16_t opcode = little_endian_read_16(packet,3);
1752         if (opcode == hci_reset.opcode){
1753             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1754             return;
1755         }
1756     }
1757 
1758     // CSR & H5
1759     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1760     if (!command_completed
1761             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1762             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1763 
1764         uint16_t opcode = little_endian_read_16(packet,3);
1765         if (opcode == hci_reset.opcode){
1766             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1767             return;
1768         }
1769     }
1770 
1771     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1772     // fix: Correct substate and behave as command below
1773     if (command_completed){
1774         switch (hci_stack->substate){
1775             case HCI_INIT_SEND_RESET:
1776                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1777                 break;
1778             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1779                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1780                 break;
1781             default:
1782                 break;
1783         }
1784     }
1785 
1786 #endif
1787 
1788     if (!command_completed) return;
1789 
1790     bool need_baud_change = false;
1791     bool need_addr_change = false;
1792 
1793 #ifndef HAVE_HOST_CONTROLLER_API
1794     need_baud_change = hci_stack->config
1795                         && hci_stack->chipset
1796                         && hci_stack->chipset->set_baudrate_command
1797                         && hci_stack->hci_transport->set_baudrate
1798                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1799 
1800     need_addr_change = hci_stack->custom_bd_addr_set
1801                         && hci_stack->chipset
1802                         && hci_stack->chipset->set_bd_addr_command;
1803 #endif
1804 
1805     switch(hci_stack->substate){
1806 
1807 #ifndef HAVE_HOST_CONTROLLER_API
1808         case HCI_INIT_SEND_RESET:
1809             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1810             // fix: just correct substate and behave as command below
1811             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1812             btstack_run_loop_remove_timer(&hci_stack->timeout);
1813             break;
1814         case HCI_INIT_W4_SEND_RESET:
1815             btstack_run_loop_remove_timer(&hci_stack->timeout);
1816             break;
1817         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1818             log_info("Received local name, need baud change %d", (int) need_baud_change);
1819             if (need_baud_change){
1820                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1821                 return;
1822             }
1823             // skip baud change
1824             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1825             return;
1826         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1827             // for STLC2500D, baud rate change already happened.
1828             // for others, baud rate gets changed now
1829             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1830                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1831                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1832                 hci_stack->hci_transport->set_baudrate(baud_rate);
1833             }
1834             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1835             return;
1836         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1837             btstack_run_loop_remove_timer(&hci_stack->timeout);
1838             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1839             return;
1840         case HCI_INIT_W4_CUSTOM_INIT:
1841             // repeat custom init
1842             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1843             return;
1844 #else
1845         case HCI_INIT_W4_SEND_RESET:
1846             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1847             return ;
1848 #endif
1849 
1850         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1851             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1852               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1853                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1854                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1855                 return;
1856             }
1857             if (need_addr_change){
1858                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1859                 return;
1860             }
1861             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1862             return;
1863 #ifndef HAVE_HOST_CONTROLLER_API
1864         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1865             if (need_baud_change){
1866                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1867                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1868                 hci_stack->hci_transport->set_baudrate(baud_rate);
1869             }
1870             if (need_addr_change){
1871                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1872                 return;
1873             }
1874             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1875             return;
1876         case HCI_INIT_W4_SET_BD_ADDR:
1877             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1878             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1879             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1880                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1881                 return;
1882             }
1883             // skipping st warm boot
1884             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1885             return;
1886         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1887             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1888             return;
1889 #endif
1890         case HCI_INIT_W4_READ_BD_ADDR:
1891             // only read buffer size if supported
1892             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1893                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1894                 return;
1895             }
1896             // skipping read buffer size
1897             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1898             return;
1899         case HCI_INIT_W4_SET_EVENT_MASK:
1900             // skip Classic init commands for LE only chipsets
1901             if (!hci_classic_supported()){
1902 #ifdef ENABLE_BLE
1903                 if (hci_le_supported()){
1904                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1905                     return;
1906                 }
1907 #endif
1908                 log_error("Neither BR/EDR nor LE supported");
1909                 hci_init_done();
1910                 return;
1911             }
1912             if (!gap_ssp_supported()){
1913                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1914                 return;
1915             }
1916             break;
1917 #ifdef ENABLE_BLE
1918         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1919             // skip write le host if not supported (e.g. on LE only EM9301)
1920             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1921             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1922             return;
1923 
1924 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1925         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1926             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1927             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1928                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1929                 return;
1930             }
1931             // explicit fall through to reduce repetitions
1932 
1933 #ifdef ENABLE_LE_CENTRAL
1934             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1935 #else
1936             hci_init_done();
1937 #endif
1938             return;
1939 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1940 
1941 #endif  /* ENABLE_BLE */
1942 
1943         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1944             // skip write secure connections host support if not supported or disabled
1945             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1946                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1947                 return;
1948             }
1949             break;
1950 
1951 #ifdef ENABLE_SCO_OVER_HCI
1952         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1953             // skip write synchronous flow control if not supported
1954             if (hci_stack->local_supported_commands[0] & 0x04) break;
1955             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1956 
1957             /* fall through */
1958 
1959         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1960             // skip write default erroneous data reporting if not supported
1961             if (hci_stack->local_supported_commands[0] & 0x08) break;
1962             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1963 
1964             /* fall through */
1965 
1966         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1967             // skip bcm set sco pcm config on non-Broadcom chipsets
1968             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1969             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1970 
1971             /* fall through */
1972 
1973         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1974             if (!hci_le_supported()){
1975                 // SKIP LE init for Classic only configuration
1976                 hci_init_done();
1977                 return;
1978             }
1979             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM;
1980             break;
1981 
1982 #else /* !ENABLE_SCO_OVER_HCI */
1983 
1984         case HCI_INIT_W4_WRITE_PAGE_TIMEOUT:
1985 #ifdef ENABLE_SCO_OVER_PCM
1986             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) {
1987                 hci_stack->substate = HCI_INIT_BCM_WRITE_SCO_PCM_INT;
1988                 return;
1989             }
1990 #endif
1991             /* fall through */
1992 
1993         case HCI_INIT_W4_BCM_WRITE_I2SPCM_INTERFACE_PARAM:
1994 #ifdef ENABLE_BLE
1995             if (hci_le_supported()){
1996                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1997                 return;
1998             }
1999 #endif
2000             // SKIP LE init for Classic only configuration
2001             hci_init_done();
2002             return;
2003 #endif /* ENABLE_SCO_OVER_HCI */
2004 
2005 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
2006 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
2007         // Response to command before init done state -> init done
2008         case (HCI_INIT_DONE-1):
2009             hci_init_done();
2010             return;
2011 #endif
2012 
2013         default:
2014             break;
2015     }
2016     hci_initializing_next_state();
2017 }
2018 
2019 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
2020     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
2021     bd_addr_t bd_address;
2022     (void)memcpy(&bd_address, conn->address, 6);
2023 
2024 #ifdef ENABLE_CLASSIC
2025     // cache needed data
2026     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
2027 #endif
2028 
2029     // connection failed, remove entry
2030     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2031     btstack_memory_hci_connection_free( conn );
2032 
2033 #ifdef ENABLE_CLASSIC
2034     // notify client if dedicated bonding
2035     if (notify_dedicated_bonding_failed){
2036         log_info("hci notify_dedicated_bonding_failed");
2037         hci_emit_dedicated_bonding_result(bd_address, status);
2038     }
2039 
2040     // if authentication error, also delete link key
2041     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
2042         gap_drop_link_key_for_bd_addr(bd_address);
2043     }
2044 #else
2045     UNUSED(status);
2046 #endif
2047 }
2048 
2049 #ifdef ENABLE_CLASSIC
2050 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
2051     // SSP Controller
2052     if (features[6] & (1 << 3)){
2053         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
2054     }
2055     // eSCO
2056     if (features[3] & (1<<7)){
2057         conn->remote_supported_features[0] |= 1;
2058     }
2059     // Extended features
2060     if (features[7] & (1<<7)){
2061         conn->remote_supported_features[0] |= 2;
2062     }
2063 }
2064 
2065 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
2066     // SSP Host
2067     if (features[0] & (1 << 0)){
2068         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
2069     }
2070     // SC Host
2071     if (features[0] & (1 << 3)){
2072         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
2073     }
2074 }
2075 
2076 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
2077     // SC Controller
2078     if (features[1] & (1 << 0)){
2079         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2080     }
2081 }
2082 
2083 static void hci_handle_remote_features_received(hci_connection_t * conn){
2084     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2085     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
2086     if (conn->bonding_flags & BONDING_DEDICATED){
2087         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2088     }
2089 }
2090 static bool hci_remote_sc_enabled(hci_connection_t * connection){
2091     const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2092     return (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
2093 }
2094 
2095 #endif
2096 
2097 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
2098     // handle BT initialization
2099     if (hci_stack->state == HCI_STATE_INITIALIZING) {
2100         hci_initializing_event_handler(packet, size);
2101     }
2102 
2103     // help with BT sleep
2104     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
2105         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
2106         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
2107         hci_initializing_next_state();
2108     }
2109 }
2110 
2111 #ifdef ENABLE_CLASSIC
2112 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
2113     conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2114     conn->encryption_key_size = encryption_key_size;
2115 
2116     if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) != 0) {
2117         conn->requested_security_level = LEVEL_0;
2118         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
2119         return;
2120     }
2121 
2122     // Request Authentication if not already done
2123     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
2124     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2125 }
2126 #endif
2127 
2128 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
2129     UNUSED(size);
2130 
2131     uint16_t manufacturer;
2132 #ifdef ENABLE_CLASSIC
2133     hci_con_handle_t handle;
2134     hci_connection_t * conn;
2135     uint8_t status;
2136 #endif
2137     // get num cmd packets - limit to 1 to reduce complexity
2138     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
2139 
2140     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
2141     switch (opcode){
2142         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
2143             if (packet[5]) break;
2144             // terminate, name 248 chars
2145             packet[6+248] = 0;
2146             log_info("local name: %s", &packet[6]);
2147             break;
2148         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2149             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2150             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2151                 uint16_t acl_len = little_endian_read_16(packet, 6);
2152                 uint16_t sco_len = packet[8];
2153 
2154                 // determine usable ACL/SCO payload size
2155                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2156                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2157 
2158                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2159                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2160 
2161                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2162                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2163                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2164             }
2165             break;
2166         case HCI_OPCODE_HCI_READ_RSSI:
2167             if (packet[5] == ERROR_CODE_SUCCESS){
2168                 uint8_t event[5];
2169                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2170                 event[1] = 3;
2171                 (void)memcpy(&event[2], &packet[6], 3);
2172                 hci_emit_event(event, sizeof(event), 1);
2173             }
2174             break;
2175 #ifdef ENABLE_BLE
2176         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2177             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2178             hci_stack->le_acl_packets_total_num = packet[8];
2179             // determine usable ACL payload size
2180             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2181                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2182             }
2183             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2184             break;
2185 #endif
2186 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2187         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2188             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2189             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2190             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);
2191             break;
2192 #endif
2193 #ifdef ENABLE_LE_CENTRAL
2194         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2195             hci_stack->le_whitelist_capacity = packet[6];
2196             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2197             break;
2198 #endif
2199         case HCI_OPCODE_HCI_READ_BD_ADDR:
2200             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2201             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));
2202 #ifdef ENABLE_CLASSIC
2203             if (hci_stack->link_key_db){
2204                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2205             }
2206 #endif
2207             break;
2208 #ifdef ENABLE_CLASSIC
2209         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2210             hci_emit_discoverable_enabled(hci_stack->discoverable);
2211             break;
2212         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2213             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2214                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2215                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2216                 hci_emit_event(event, sizeof(event), 1);
2217             }
2218             break;
2219 #endif
2220         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2221             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2222 
2223 #ifdef ENABLE_CLASSIC
2224             // determine usable ACL packet types based on host buffer size and supported features
2225             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2226             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2227 #endif
2228             // Classic/LE
2229             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2230             break;
2231         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2232             manufacturer = little_endian_read_16(packet, 10);
2233             // map Cypress to Broadcom
2234             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2235                 log_info("Treat Cypress as Broadcom");
2236                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2237                 little_endian_store_16(packet, 10, manufacturer);
2238             }
2239             hci_stack->manufacturer = manufacturer;
2240             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2241             break;
2242         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2243             hci_stack->local_supported_commands[0] =
2244                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit  0 = Octet 14, bit 7 / Read Buffer Size
2245                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit  1 = Octet 24, bit 6 / Write Le Host Supported
2246                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit  2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2247                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     )  |  // bit  3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2248                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit  4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2249                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit  5 = Octet 35, bit 3 / LE Read Maximum Data Length
2250                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit  6 = Octet 35, bit 5 / LE Set Default PHY
2251                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit  7 = Octet 20, bit 4 / Read Encryption Key Size
2252             hci_stack->local_supported_commands[1] =
2253                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit  8 = Octet  2, bit 6 / Read Remote Extended Features
2254                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u) |  // bit  9 = Octet 32, bit 3 / Write Secure Connections Host
2255                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x02u) << 1u) |  // bit 10 = Octet 35, bit 1 / LE Set Address Resolution Enable
2256                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x02u) << 2u) |  // bit 11 = Octet 32, bit 1 / Remote OOB Extended Data Request Reply
2257                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x40u) >> 2u);   // bit 12 = Octet 32, bit 6 / Read Local OOB Extended Data command
2258             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2259             break;
2260 #ifdef ENABLE_CLASSIC
2261         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2262             if (packet[5]) return;
2263             hci_stack->synchronous_flow_control_enabled = 1;
2264             break;
2265         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2266             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2267             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2268             conn   = hci_connection_for_handle(handle);
2269             if (conn != NULL) {
2270                 uint8_t key_size = 0;
2271                 if (status == 0){
2272                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2273                     log_info("Handle %04x key Size: %u", handle, key_size);
2274                 } else {
2275                     key_size = 1;
2276                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2277                 }
2278                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2279             }
2280             break;
2281         // assert pairing complete event is emitted.
2282         // note: for SSP, Simple Pairing Complete Event is sufficient, but we want to be more robust
2283         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
2284         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
2285         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
2286             hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
2287             // lookup connection by gap pairing addr
2288             conn = hci_connection_for_bd_addr_and_type(hci_stack->gap_pairing_addr, BD_ADDR_TYPE_ACL);
2289             if (conn == NULL) break;
2290             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2291             break;
2292 
2293 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2294         case HCI_OPCODE_HCI_READ_LOCAL_OOB_DATA:
2295         case HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA:{
2296             uint8_t event[67];
2297             event[0] = GAP_EVENT_LOCAL_OOB_DATA;
2298             event[1] = 65;
2299             (void)memset(&event[2], 0, 65);
2300             if (packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE] == ERROR_CODE_SUCCESS){
2301                 (void)memcpy(&event[3], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 32);
2302                 if (opcode == HCI_OPCODE_HCI_READ_LOCAL_EXTENDED_OOB_DATA){
2303                     event[2] = 3;
2304                     (void)memcpy(&event[35], &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+33], 32);
2305                 } else {
2306                     event[2] = 1;
2307                 }
2308             }
2309             hci_emit_event(event, sizeof(event), 0);
2310             break;
2311         }
2312 
2313         // note: only needed if user does not provide OOB data
2314         case HCI_OPCODE_HCI_REMOTE_OOB_DATA_REQUEST_NEGATIVE_REPLY:
2315             conn = hci_connection_for_handle(hci_stack->classic_oob_con_handle);
2316             hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
2317             if (conn == NULL) break;
2318             hci_pairing_complete(conn, ERROR_CODE_AUTHENTICATION_FAILURE);
2319             break;
2320 #endif
2321 #endif
2322         default:
2323             break;
2324     }
2325 }
2326 
2327 #ifdef ENABLE_BLE
2328 static void event_handle_le_connection_complete(const uint8_t * packet){
2329 	bd_addr_t addr;
2330 	bd_addr_type_t addr_type;
2331 	hci_connection_t * conn;
2332 
2333 	// Connection management
2334 	reverse_bd_addr(&packet[8], addr);
2335 	addr_type = (bd_addr_type_t)packet[7];
2336 	log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2337 	conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2338 
2339 #ifdef ENABLE_LE_CENTRAL
2340 	// handle error: error is reported only to the initiator -> outgoing connection
2341 	if (packet[3]){
2342 
2343 		// handle cancelled outgoing connection
2344 		// "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2345 		//  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2346 		//  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2347 		if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2348 		    // reset state
2349             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2350             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2351 			// get outgoing connection conn struct for direct connect
2352 			conn = gap_get_outgoing_connection();
2353 		}
2354 
2355 		// outgoing le connection establishment is done
2356 		if (conn){
2357 			// remove entry
2358 			btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2359 			btstack_memory_hci_connection_free( conn );
2360 		}
2361 		return;
2362 	}
2363 #endif
2364 
2365 	// on success, both hosts receive connection complete event
2366 	if (packet[6] == HCI_ROLE_MASTER){
2367 #ifdef ENABLE_LE_CENTRAL
2368 		// if we're master on an le connection, it was an outgoing connection and we're done with it
2369 		// note: no hci_connection_t object exists yet for connect with whitelist
2370 		if (hci_is_le_connection_type(addr_type)){
2371 			hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2372 			hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2373 		}
2374 #endif
2375 	} else {
2376 #ifdef ENABLE_LE_PERIPHERAL
2377 		// if we're slave, it was an incoming connection, advertisements have stopped
2378 		hci_stack->le_advertisements_active = false;
2379 #endif
2380 	}
2381 
2382 	// LE connections are auto-accepted, so just create a connection if there isn't one already
2383 	if (!conn){
2384 		conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2385 	}
2386 
2387 	// no memory, sorry.
2388 	if (!conn){
2389 		return;
2390 	}
2391 
2392 	conn->state = OPEN;
2393 	conn->role  = packet[6];
2394 	conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2395 	conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2396 
2397 #ifdef ENABLE_LE_PERIPHERAL
2398 	if (packet[6] == HCI_ROLE_SLAVE){
2399 		hci_update_advertisements_enabled_for_current_roles();
2400 	}
2401 #endif
2402 
2403     // init unenhanced att bearer mtu
2404     conn->att_connection.mtu = ATT_DEFAULT_MTU;
2405     conn->att_connection.mtu_exchanged = false;
2406 
2407     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2408 
2409 	// restart timer
2410 	// btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2411 	// btstack_run_loop_add_timer(&conn->timeout);
2412 
2413 	log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2414 
2415 	hci_emit_nr_connections_changed();
2416 }
2417 #endif
2418 
2419 #ifdef ENABLE_CLASSIC
2420 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){
2421     if (io_cap_local == SSP_IO_CAPABILITY_UNKNOWN) return false;
2422     // LEVEL_4 is tested by l2cap
2423     // LEVEL 3 requires MITM protection -> check io capabilities if Authenticated is possible
2424     // @see: Core Spec v5.3, Vol 3, Part C, Table 5.7
2425     if (level >= LEVEL_3){
2426         // MITM not possible without keyboard or display
2427         if (io_cap_remote >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2428         if (io_cap_local  >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT) return false;
2429 
2430         // MITM possible if one side has keyboard and the other has keyboard or display
2431         if (io_cap_remote == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2432         if (io_cap_local  == SSP_IO_CAPABILITY_KEYBOARD_ONLY)      return true;
2433 
2434         // MITM not possible if one side has only display and other side has no keyboard
2435         if (io_cap_remote == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2436         if (io_cap_local  == SSP_IO_CAPABILITY_DISPLAY_ONLY)       return false;
2437     }
2438     // LEVEL 2 requires SSP, which is a given
2439     return true;
2440 }
2441 
2442 static bool btstack_is_null(uint8_t * data, uint16_t size){
2443     uint16_t i;
2444     for (i=0; i < size ; i++){
2445         if (data[i] != 0) {
2446             return false;
2447         }
2448     }
2449     return true;
2450 }
2451 
2452 static void hci_ssp_assess_security_on_io_cap_request(hci_connection_t * conn){
2453     // get requested security level
2454     gap_security_level_t requested_security_level = conn->requested_security_level;
2455     if (hci_stack->gap_secure_connections_only_mode){
2456         requested_security_level = LEVEL_4;
2457     }
2458 
2459     // assess security: LEVEL 4 requires SC
2460     // skip this preliminary test if remote features are not available yet to work around potential issue in ESP32 controller
2461     if ((requested_security_level == LEVEL_4) &&
2462         ((conn->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0) &&
2463         !hci_remote_sc_enabled(conn)){
2464         log_info("Level 4 required, but SC not supported -> abort");
2465         hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2466         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2467         return;
2468     }
2469 
2470     // assess security based on io capabilities
2471     if (conn->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
2472         // responder: fully validate io caps of both sides as well as OOB data
2473         bool security_possible = false;
2474         security_possible = hci_ssp_security_level_possible_for_io_cap(requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io);
2475 
2476 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2477         // We assume that both Controller can reach LEVEL 4, if one side has received P-192 and the other has received P-256,
2478         // so we merge the OOB data availability
2479         uint8_t have_oob_data = conn->io_cap_response_oob_data;
2480         if (conn->classic_oob_c_192 != NULL){
2481             have_oob_data |= 1;
2482         }
2483         if (conn->classic_oob_c_256 != NULL){
2484             have_oob_data |= 2;
2485         }
2486         // for up to Level 3, either P-192 as well as P-256 will do
2487         // 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
2488         // if remote does not SC, we should not receive P-256 data either
2489         if ((requested_security_level <= LEVEL_3) && (have_oob_data != 0)){
2490             security_possible = true;
2491         }
2492         // for Level 4, P-256 is needed
2493         if ((requested_security_level == LEVEL_4 && ((have_oob_data & 2) != 0))){
2494             security_possible = true;
2495         }
2496 #endif
2497 
2498         if (security_possible == false){
2499             log_info("IOCap/OOB insufficient for level %u -> abort", requested_security_level);
2500             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2501             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2502             return;
2503         }
2504     } else {
2505         // initiator: remote io cap not yet, only check if we have ability for MITM protection if requested and OOB is not supported
2506 #ifndef ENABLE_CLASSIC_PAIRING_OOB
2507 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2508         if ((conn->requested_security_level >= LEVEL_3) && (hci_stack->ssp_io_capability >= SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT)){
2509             log_info("Level 3+ required, but no input/output -> abort");
2510             hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2511             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2512             return;
2513         }
2514 #endif
2515 #endif
2516     }
2517 
2518 #ifndef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
2519     if (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN){
2520         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
2521     } else {
2522         connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
2523     }
2524 #endif
2525 }
2526 
2527 #endif
2528 
2529 static void event_handler(uint8_t *packet, uint16_t size){
2530 
2531     uint16_t event_length = packet[1];
2532 
2533     // assert packet is complete
2534     if (size != (event_length + 2u)){
2535         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2536         return;
2537     }
2538 
2539     bd_addr_type_t addr_type;
2540     hci_con_handle_t handle;
2541     hci_connection_t * conn;
2542     int i;
2543     int create_connection_cmd;
2544 
2545 #ifdef ENABLE_CLASSIC
2546     hci_link_type_t link_type;
2547     bd_addr_t addr;
2548 #endif
2549 
2550     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2551 
2552     switch (hci_event_packet_get_type(packet)) {
2553 
2554         case HCI_EVENT_COMMAND_COMPLETE:
2555             handle_command_complete_event(packet, size);
2556             break;
2557 
2558         case HCI_EVENT_COMMAND_STATUS:
2559             // get num cmd packets - limit to 1 to reduce complexity
2560             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2561 
2562             // check command status to detected failed outgoing connections
2563             create_connection_cmd = 0;
2564 #ifdef ENABLE_CLASSIC
2565             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2566                 create_connection_cmd = 1;
2567             }
2568 #endif
2569 #ifdef ENABLE_LE_CENTRAL
2570             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2571                 create_connection_cmd = 1;
2572             }
2573 #endif
2574             if (create_connection_cmd) {
2575                 uint8_t status = hci_event_command_status_get_status(packet);
2576                 addr_type = hci_stack->outgoing_addr_type;
2577                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, addr_type);
2578                 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);
2579 
2580                 // reset outgoing address info
2581                 memset(hci_stack->outgoing_addr, 0, 6);
2582                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2583 
2584                 // on error
2585                 if (status != ERROR_CODE_SUCCESS){
2586 #ifdef ENABLE_LE_CENTRAL
2587                     if (hci_is_le_connection_type(addr_type)){
2588                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2589                         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2590                     }
2591 #endif
2592                     // error => outgoing connection failed
2593                     if (conn != NULL){
2594                         hci_handle_connection_failed(conn, status);
2595                     }
2596                 }
2597             }
2598 
2599 #ifdef ENABLE_CLASSIC
2600             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_inquiry)) {
2601                 uint8_t status = hci_event_command_status_get_status(packet);
2602                 log_info("command status (inquiry), status %x", status);
2603                 if (status == ERROR_CODE_SUCCESS) {
2604                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
2605                 } else {
2606                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2607                 }
2608             }
2609 #endif
2610             break;
2611 
2612         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2613             if (size < 3) return;
2614             uint16_t num_handles = packet[2];
2615             if (size != (3u + num_handles * 4u)) return;
2616             uint16_t offset = 3;
2617             for (i=0; i<num_handles;i++){
2618                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2619                 offset += 2u;
2620                 uint16_t num_packets = little_endian_read_16(packet, offset);
2621                 offset += 2u;
2622 
2623                 conn = hci_connection_for_handle(handle);
2624                 if (!conn){
2625                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2626                     continue;
2627                 }
2628 
2629                 if (conn->num_packets_sent >= num_packets){
2630                     conn->num_packets_sent -= num_packets;
2631                 } else {
2632                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2633                     conn->num_packets_sent = 0;
2634                 }
2635                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2636 
2637 #ifdef ENABLE_CLASSIC
2638                 // For SCO, we do the can_send_now_check here
2639                 hci_notify_if_sco_can_send_now();
2640 #endif
2641             }
2642             break;
2643         }
2644 
2645 #ifdef ENABLE_CLASSIC
2646         case HCI_EVENT_INQUIRY_COMPLETE:
2647             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2648                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2649                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2650                 hci_emit_event(event, sizeof(event), 1);
2651             }
2652             break;
2653         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2654             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2655                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2656             }
2657             break;
2658         case HCI_EVENT_CONNECTION_REQUEST:
2659             reverse_bd_addr(&packet[2], addr);
2660             link_type = (hci_link_type_t) packet[11];
2661 
2662             // CVE-2020-26555: reject incoming connection from device with same BD ADDR
2663             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0){
2664                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2665                 bd_addr_copy(hci_stack->decline_addr, addr);
2666                 break;
2667             }
2668 
2669             if (hci_stack->gap_classic_accept_callback != NULL){
2670                 if ((*hci_stack->gap_classic_accept_callback)(addr, link_type) == 0){
2671                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2672                     bd_addr_copy(hci_stack->decline_addr, addr);
2673                     break;
2674                 }
2675             }
2676 
2677             // TODO: eval COD 8-10
2678             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), (unsigned int) link_type);
2679             addr_type = (link_type == HCI_LINK_TYPE_ACL) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2680             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2681             if (!conn) {
2682                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2683             }
2684             if (!conn) {
2685                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2686                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2687                 bd_addr_copy(hci_stack->decline_addr, addr);
2688                 break;
2689             }
2690             conn->role  = HCI_ROLE_SLAVE;
2691             conn->state = RECEIVED_CONNECTION_REQUEST;
2692             // store info about eSCO
2693             if (link_type == HCI_LINK_TYPE_ESCO){
2694                 conn->remote_supported_features[0] |= 1;
2695             }
2696             hci_run();
2697             break;
2698 
2699         case HCI_EVENT_CONNECTION_COMPLETE:
2700             // Connection management
2701             reverse_bd_addr(&packet[5], addr);
2702             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2703             addr_type = BD_ADDR_TYPE_ACL;
2704             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2705             if (conn) {
2706                 if (!packet[2]){
2707                     conn->state = OPEN;
2708                     conn->con_handle = little_endian_read_16(packet, 3);
2709 
2710                     // queue get remote feature
2711                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2712 
2713                     // queue set supervision timeout if we're master
2714                     if ((hci_stack->link_supervision_timeout != HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT) && (conn->role == HCI_ROLE_MASTER)){
2715                         connectionSetAuthenticationFlags(conn, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
2716                     }
2717 
2718                     // restart timer
2719                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2720                     btstack_run_loop_add_timer(&conn->timeout);
2721 
2722                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2723 
2724                     hci_emit_nr_connections_changed();
2725                 } else {
2726                     // connection failed
2727                     hci_handle_connection_failed(conn, packet[2]);
2728                 }
2729             }
2730             break;
2731 
2732         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2733             reverse_bd_addr(&packet[5], addr);
2734             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2735             if (packet[2]){
2736                 // connection failed
2737                 break;
2738             }
2739             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2740             if (!conn) {
2741                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2742             }
2743             if (!conn) {
2744                 break;
2745             }
2746             conn->state = OPEN;
2747             conn->con_handle = little_endian_read_16(packet, 3);
2748 
2749 #ifdef ENABLE_SCO_OVER_HCI
2750             // update SCO
2751             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2752                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2753             }
2754             // trigger can send now
2755             if (hci_have_usb_transport()){
2756                 hci_stack->sco_can_send_now = true;
2757             }
2758 #endif
2759 #ifdef HAVE_SCO_TRANSPORT
2760             // configure sco transport
2761             if (hci_stack->sco_transport != NULL){
2762                 sco_format_t sco_format = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? SCO_FORMAT_8_BIT : SCO_FORMAT_16_BIT;
2763                 hci_stack->sco_transport->open(conn->con_handle, sco_format);
2764             }
2765 #endif
2766             break;
2767 
2768         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2769             handle = little_endian_read_16(packet, 3);
2770             conn = hci_connection_for_handle(handle);
2771             if (!conn) break;
2772             if (!packet[2]){
2773                 const uint8_t * features = &packet[5];
2774                 hci_handle_remote_features_page_0(conn, features);
2775 
2776                 // read extended features if possible
2777                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2778                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2779                     break;
2780                 }
2781             }
2782             hci_handle_remote_features_received(conn);
2783             break;
2784 
2785         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2786             handle = little_endian_read_16(packet, 3);
2787             conn = hci_connection_for_handle(handle);
2788             if (!conn) break;
2789             // status = ok, page = 1
2790             if (!packet[2]) {
2791                 uint8_t page_number = packet[5];
2792                 uint8_t maximum_page_number = packet[6];
2793                 const uint8_t * features = &packet[7];
2794                 bool done = false;
2795                 switch (page_number){
2796                     case 1:
2797                         hci_handle_remote_features_page_1(conn, features);
2798                         if (maximum_page_number >= 2){
2799                             // get Secure Connections (Controller) from Page 2 if available
2800                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2801                         } else {
2802                             // otherwise, assume SC (Controller) == SC (Host)
2803                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2804                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2805                             }
2806                             done = true;
2807                         }
2808                         break;
2809                     case 2:
2810                         hci_handle_remote_features_page_2(conn, features);
2811                         done = true;
2812                         break;
2813                     default:
2814                         break;
2815                 }
2816                 if (!done) break;
2817             }
2818             hci_handle_remote_features_received(conn);
2819             break;
2820 
2821         case HCI_EVENT_LINK_KEY_REQUEST:
2822 #ifndef ENABLE_EXPLICIT_LINK_KEY_REPLY
2823             hci_event_link_key_request_get_bd_addr(packet, addr);
2824             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2825             if (!conn) break;
2826 
2827             // lookup link key in db if not cached
2828             if ((conn->link_key_type == INVALID_LINK_KEY) && (hci_stack->link_key_db != NULL)){
2829                 hci_stack->link_key_db->get_link_key(conn->address, conn->link_key, &conn->link_key_type);
2830             }
2831 
2832             // response sent by hci_run()
2833             conn->authentication_flags |= AUTH_FLAG_HANDLE_LINK_KEY_REQUEST;
2834 #endif
2835             break;
2836 
2837         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2838             hci_event_link_key_request_get_bd_addr(packet, addr);
2839             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2840             if (!conn) break;
2841 
2842             hci_pairing_complete(conn, ERROR_CODE_SUCCESS);
2843 
2844             // CVE-2020-26555: ignore NULL link key
2845             // default link_key_type = INVALID_LINK_KEY asserts that NULL key won't be used for encryption
2846             if (btstack_is_null(&packet[8], 16)) break;
2847 
2848             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2849             // Change Connection Encryption keeps link key type
2850             if (link_key_type != CHANGED_COMBINATION_KEY){
2851                 conn->link_key_type = link_key_type;
2852             }
2853 
2854             // cache link key. link keys stored in little-endian format for legacy reasons
2855             memcpy(&conn->link_key, &packet[8], 16);
2856 
2857             // only store link key:
2858             // - if bondable enabled
2859             if (hci_stack->bondable == false) break;
2860             // - if security level sufficient
2861             if (gap_security_level_for_link_key_type(link_key_type) < conn->requested_security_level) break;
2862             // - for SSP, also check if remote side requested bonding as well
2863             if (conn->link_key_type != COMBINATION_KEY){
2864                 bool remote_bonding = conn->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
2865                 if (!remote_bonding){
2866                     break;
2867                 }
2868             }
2869             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2870             break;
2871         }
2872 
2873         case HCI_EVENT_PIN_CODE_REQUEST:
2874             hci_event_pin_code_request_get_bd_addr(packet, addr);
2875             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2876             if (!conn) break;
2877 
2878             hci_pairing_started(conn, false);
2879             // abort pairing if: non-bondable mode (pin code request is not forwarded to app)
2880             if (!hci_stack->bondable ){
2881                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2882                 hci_pairing_complete(conn, ERROR_CODE_PAIRING_NOT_ALLOWED);
2883                 hci_run();
2884                 return;
2885             }
2886             // abort pairing if: LEVEL_4 required (pin code request is not forwarded to app)
2887             if ((hci_stack->gap_secure_connections_only_mode) || (conn->requested_security_level == LEVEL_4)){
2888                 log_info("Level 4 required, but SC not supported -> abort");
2889                 conn->authentication_flags |= AUTH_FLAG_DENY_PIN_CODE_REQUEST;
2890                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2891                 hci_run();
2892                 return;
2893             }
2894             break;
2895 
2896         case HCI_EVENT_IO_CAPABILITY_RESPONSE:
2897             hci_event_io_capability_response_get_bd_addr(packet, addr);
2898             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2899             if (!conn) break;
2900 
2901             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE);
2902             hci_pairing_started(conn, true);
2903             conn->io_cap_response_auth_req = hci_event_io_capability_response_get_authentication_requirements(packet);
2904             conn->io_cap_response_io       = hci_event_io_capability_response_get_io_capability(packet);
2905 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2906             conn->io_cap_response_oob_data = hci_event_io_capability_response_get_oob_data_present(packet);
2907 #endif
2908             break;
2909 
2910         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2911             hci_event_io_capability_response_get_bd_addr(packet, addr);
2912             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2913             if (!conn) break;
2914 
2915             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
2916             hci_connection_timestamp(conn);
2917             hci_pairing_started(conn, true);
2918             break;
2919 
2920 #ifdef ENABLE_CLASSIC_PAIRING_OOB
2921         case HCI_EVENT_REMOTE_OOB_DATA_REQUEST:
2922             hci_event_remote_oob_data_request_get_bd_addr(packet, addr);
2923             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2924             if (!conn) break;
2925 
2926             hci_connection_timestamp(conn);
2927 
2928             hci_pairing_started(conn, true);
2929 
2930             connectionSetAuthenticationFlags(conn, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
2931             break;
2932 #endif
2933 
2934         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2935             hci_event_user_confirmation_request_get_bd_addr(packet, addr);
2936             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2937             if (!conn) break;
2938             if (hci_ssp_security_level_possible_for_io_cap(conn->requested_security_level, hci_stack->ssp_io_capability, conn->io_cap_response_io)) {
2939                 if (hci_stack->ssp_auto_accept){
2940                     hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
2941                 };
2942             } else {
2943                 hci_pairing_complete(conn, ERROR_CODE_INSUFFICIENT_SECURITY);
2944                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
2945                 // don't forward event to app
2946                 hci_run();
2947                 return;
2948             }
2949             break;
2950 
2951         case HCI_EVENT_USER_PASSKEY_REQUEST:
2952             // Pairing using Passkey results in MITM protection. If Level 4 is required, support for SC is validated on IO Cap Request
2953             if (hci_stack->ssp_auto_accept){
2954                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
2955             };
2956             break;
2957 
2958         case HCI_EVENT_MODE_CHANGE:
2959             handle = hci_event_mode_change_get_handle(packet);
2960             conn = hci_connection_for_handle(handle);
2961             if (!conn) break;
2962             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2963             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2964             break;
2965 #endif
2966 
2967         case HCI_EVENT_ENCRYPTION_CHANGE:
2968             handle = hci_event_encryption_change_get_connection_handle(packet);
2969             conn = hci_connection_for_handle(handle);
2970             if (!conn) break;
2971             if (hci_event_encryption_change_get_status(packet) == 0u) {
2972                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2973                 if (encryption_enabled){
2974                     if (hci_is_le_connection(conn)){
2975                         // For LE, we accept connection as encrypted
2976                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_ENCRYPTED;
2977                     }
2978 #ifdef ENABLE_CLASSIC
2979                     else {
2980 
2981                         // dedicated bonding: send result and disconnect
2982                         if (conn->bonding_flags & BONDING_DEDICATED){
2983                             conn->bonding_flags &= ~BONDING_DEDICATED;
2984                             conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2985                             conn->bonding_status = packet[2];
2986                             break;
2987                         }
2988 
2989                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2990                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2991                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2992                         if (hci_stack->secure_connections_active && sc_used_during_pairing && !connected_uses_aes_ccm){
2993                             log_info("SC during pairing, but only E0 now -> abort");
2994                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2995                             break;
2996                         }
2997 
2998                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2999                         if (connected_uses_aes_ccm){
3000                             conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3001                         }
3002 
3003 #ifdef ENABLE_TESTING_SUPPORT
3004                         // work around for issue with PTS dongle
3005                         conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3006 #endif
3007 
3008                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
3009                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
3010                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3011                         } else {
3012                             // if not, pretend everything is perfect
3013                             hci_handle_read_encryption_key_size_complete(conn, 16);
3014                         }
3015                     }
3016 #endif
3017                 } else {
3018                     conn->authentication_flags &= ~AUTH_FLAG_CONNECTION_ENCRYPTED;
3019                 }
3020             }
3021 
3022             break;
3023 
3024 #ifdef ENABLE_CLASSIC
3025         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
3026             handle = hci_event_authentication_complete_get_connection_handle(packet);
3027             conn = hci_connection_for_handle(handle);
3028             if (!conn) break;
3029 
3030             // clear authentication active flag
3031             conn->bonding_flags &= ~BONDING_SENT_AUTHENTICATE_REQUEST;
3032             hci_pairing_complete(conn, hci_event_authentication_complete_get_status(packet));
3033 
3034             // authenticated only if auth status == 0
3035             if (hci_event_authentication_complete_get_status(packet) == 0){
3036                 // authenticated
3037                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3038 
3039                 // If not already encrypted, start encryption
3040                 if ((conn->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0){
3041                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
3042                     break;
3043                 }
3044             }
3045 
3046             // emit updated security level
3047             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
3048             break;
3049 
3050         case HCI_EVENT_SIMPLE_PAIRING_COMPLETE:
3051             hci_event_simple_pairing_complete_get_bd_addr(packet, addr);
3052             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
3053             if (!conn) break;
3054 
3055             // treat successfully paired connection as authenticated
3056             if (hci_event_simple_pairing_complete_get_status(packet) == ERROR_CODE_SUCCESS){
3057                 conn->authentication_flags |= AUTH_FLAG_CONNECTION_AUTHENTICATED;
3058             }
3059 
3060             hci_pairing_complete(conn, hci_event_simple_pairing_complete_get_status(packet));
3061             break;
3062 #endif
3063 
3064         // HCI_EVENT_DISCONNECTION_COMPLETE
3065         // has been split, to first notify stack before shutting connection down
3066         // see end of function, too.
3067         case HCI_EVENT_DISCONNECTION_COMPLETE:
3068             if (packet[2]) break;   // status != 0
3069             handle = little_endian_read_16(packet, 3);
3070             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
3071             if (hci_stack->acl_fragmentation_total_size > 0u) {
3072                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
3073                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
3074                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
3075                     hci_stack->acl_fragmentation_total_size = 0;
3076                     hci_stack->acl_fragmentation_pos = 0;
3077                     if (release_buffer){
3078                         hci_release_packet_buffer();
3079                     }
3080                 }
3081             }
3082 
3083             conn = hci_connection_for_handle(handle);
3084             if (!conn) break;
3085 #ifdef ENABLE_CLASSIC
3086             // pairing failed if it was ongoing
3087             hci_pairing_complete(conn, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3088 #endif
3089 
3090             // emit dedicatd bonding event
3091             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
3092                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
3093             }
3094 
3095             // mark connection for shutdown, stop timers, reset state
3096             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
3097             hci_connection_stop_timer(conn);
3098             hci_connection_init(conn);
3099 
3100 #ifdef ENABLE_BLE
3101 #ifdef ENABLE_LE_PERIPHERAL
3102             // re-enable advertisements for le connections if active
3103             if (hci_is_le_connection(conn)){
3104                 hci_update_advertisements_enabled_for_current_roles();
3105             }
3106 #endif
3107 #endif
3108             break;
3109 
3110         case HCI_EVENT_HARDWARE_ERROR:
3111             log_error("Hardware Error: 0x%02x", packet[2]);
3112             if (hci_stack->hardware_error_callback){
3113                 (*hci_stack->hardware_error_callback)(packet[2]);
3114             } else {
3115                 // if no special requests, just reboot stack
3116                 hci_power_control_off();
3117                 hci_power_control_on();
3118             }
3119             break;
3120 
3121 #ifdef ENABLE_CLASSIC
3122         case HCI_EVENT_ROLE_CHANGE:
3123             if (packet[2]) break;   // status != 0
3124             reverse_bd_addr(&packet[3], addr);
3125             addr_type = BD_ADDR_TYPE_ACL;
3126             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
3127             if (!conn) break;
3128             conn->role = packet[9];
3129             break;
3130 #endif
3131 
3132         case HCI_EVENT_TRANSPORT_PACKET_SENT:
3133             // release packet buffer only for asynchronous transport and if there are not further fragements
3134             if (hci_transport_synchronous()) {
3135                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
3136                 return; // instead of break: to avoid re-entering hci_run()
3137             }
3138             hci_stack->acl_fragmentation_tx_active = 0;
3139             if (hci_stack->acl_fragmentation_total_size) break;
3140             hci_release_packet_buffer();
3141 
3142             // L2CAP receives this event via the hci_emit_event below
3143 
3144 #ifdef ENABLE_CLASSIC
3145             // For SCO, we do the can_send_now_check here
3146             hci_notify_if_sco_can_send_now();
3147 #endif
3148             break;
3149 
3150 #ifdef ENABLE_CLASSIC
3151         case HCI_EVENT_SCO_CAN_SEND_NOW:
3152             // For SCO, we do the can_send_now_check here
3153             hci_stack->sco_can_send_now = true;
3154             hci_notify_if_sco_can_send_now();
3155             return;
3156 
3157         // explode inquriy results for easier consumption
3158         case HCI_EVENT_INQUIRY_RESULT:
3159         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
3160         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
3161             gap_inquiry_explode(packet, size);
3162             break;
3163 #endif
3164 
3165 #ifdef ENABLE_BLE
3166         case HCI_EVENT_LE_META:
3167             switch (packet[2]){
3168 #ifdef ENABLE_LE_CENTRAL
3169                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
3170                     // log_info("advertising report received");
3171                     if (!hci_stack->le_scanning_enabled) break;
3172                     le_handle_advertisement_report(packet, size);
3173                     break;
3174 #endif
3175                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
3176 					event_handle_le_connection_complete(packet);
3177                     break;
3178 
3179                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
3180                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
3181                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
3182                     conn = hci_connection_for_handle(handle);
3183                     if (!conn) break;
3184                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
3185                     break;
3186 
3187                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
3188                     // connection
3189                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
3190                     conn = hci_connection_for_handle(handle);
3191                     if (conn) {
3192                         // read arguments
3193                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
3194                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
3195                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
3196                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
3197 
3198                         // validate against current connection parameter range
3199                         le_connection_parameter_range_t existing_range;
3200                         gap_get_connection_parameter_range(&existing_range);
3201                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
3202                         if (update_parameter){
3203                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
3204                             conn->le_conn_interval_min = le_conn_interval_min;
3205                             conn->le_conn_interval_max = le_conn_interval_max;
3206                             conn->le_conn_latency = le_conn_latency;
3207                             conn->le_supervision_timeout = le_supervision_timeout;
3208                         } else {
3209                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NEGATIVE_REPLY;
3210                         }
3211                     }
3212                     break;
3213 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
3214                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
3215                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
3216                     conn = hci_connection_for_handle(handle);
3217                     if (conn) {
3218                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
3219                     }
3220                     break;
3221 #endif
3222                 default:
3223                     break;
3224             }
3225             break;
3226 #endif
3227         case HCI_EVENT_VENDOR_SPECIFIC:
3228             // Vendor specific commands often create vendor specific event instead of num completed packets
3229             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
3230             switch (hci_stack->manufacturer){
3231                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
3232                     hci_stack->num_cmd_packets = 1;
3233                     break;
3234                 default:
3235                     break;
3236             }
3237             break;
3238         default:
3239             break;
3240     }
3241 
3242     handle_event_for_current_stack_state(packet, size);
3243 
3244     // notify upper stack
3245 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
3246 
3247     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
3248     if ((hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE) && (packet[2] == 0)){
3249 		handle = little_endian_read_16(packet, 3);
3250 		hci_connection_t * aConn = hci_connection_for_handle(handle);
3251 		// discard connection if app did not trigger a reconnect in the event handler
3252 		if (aConn && aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
3253 			hci_shutdown_connection(aConn);
3254 		}
3255     }
3256 
3257 	// execute main loop
3258 	hci_run();
3259 }
3260 
3261 #ifdef ENABLE_CLASSIC
3262 
3263 #ifdef ENABLE_SCO_OVER_HCI
3264 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
3265 static void sco_schedule_tx(hci_connection_t * conn);
3266 
3267 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
3268     log_debug("SCO TX Timeout");
3269     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
3270     hci_connection_t * conn = hci_connection_for_handle(con_handle);
3271     if (!conn) return;
3272 
3273     // trigger send
3274     conn->sco_tx_ready = 1;
3275     // extra packet if CVSD but SCO buffer is too short
3276     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
3277         conn->sco_tx_ready++;
3278     }
3279     hci_notify_if_sco_can_send_now();
3280 }
3281 
3282 
3283 #define SCO_TX_AFTER_RX_MS (6)
3284 
3285 static void sco_schedule_tx(hci_connection_t * conn){
3286 
3287     uint32_t now = btstack_run_loop_get_time_ms();
3288     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
3289     int time_delta_ms = sco_tx_ms - now;
3290 
3291     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
3292 
3293     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
3294     btstack_run_loop_remove_timer(timer);
3295     btstack_run_loop_set_timer(timer, time_delta_ms);
3296     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
3297     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
3298     btstack_run_loop_add_timer(timer);
3299 }
3300 #endif
3301 
3302 static void sco_handler(uint8_t * packet, uint16_t size){
3303     // lookup connection struct
3304     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
3305     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
3306     if (!conn) return;
3307 
3308 #ifdef ENABLE_SCO_OVER_HCI
3309     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
3310     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
3311         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
3312             packet[2] = 0x3c;
3313             memmove(&packet[3], &packet[23], 63);
3314             size = 63;
3315         }
3316     }
3317 
3318     if (hci_have_usb_transport()){
3319         // Nothing to do
3320     } else {
3321         // 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);
3322         if (hci_stack->synchronous_flow_control_enabled == 0){
3323             uint32_t now = btstack_run_loop_get_time_ms();
3324 
3325             if (!conn->sco_rx_valid){
3326                 // ignore first 10 packets
3327                 conn->sco_rx_count++;
3328                 // log_debug("sco rx count %u", conn->sco_rx_count);
3329                 if (conn->sco_rx_count == 10) {
3330                     // use first timestamp as is and pretent it just started
3331                     conn->sco_rx_ms = now;
3332                     conn->sco_rx_valid = 1;
3333                     conn->sco_rx_count = 0;
3334                     sco_schedule_tx(conn);
3335                 }
3336             } else {
3337                 // track expected arrival timme
3338                 conn->sco_rx_count++;
3339                 conn->sco_rx_ms += 7;
3340                 int delta = (int32_t) (now - conn->sco_rx_ms);
3341                 if (delta > 0){
3342                     conn->sco_rx_ms++;
3343                 }
3344                 // log_debug("sco rx %u", conn->sco_rx_ms);
3345                 sco_schedule_tx(conn);
3346             }
3347         }
3348     }
3349 #endif
3350 
3351     // deliver to app
3352     if (hci_stack->sco_packet_handler) {
3353         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
3354     }
3355 
3356 #ifdef HAVE_SCO_TRANSPORT
3357     // We can send one packet for each received packet
3358     conn->sco_tx_ready++;
3359     hci_notify_if_sco_can_send_now();
3360 #endif
3361 
3362 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3363     conn->num_packets_completed++;
3364     hci_stack->host_completed_packets = 1;
3365     hci_run();
3366 #endif
3367 }
3368 #endif
3369 
3370 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
3371     hci_dump_packet(packet_type, 1, packet, size);
3372     switch (packet_type) {
3373         case HCI_EVENT_PACKET:
3374             event_handler(packet, size);
3375             break;
3376         case HCI_ACL_DATA_PACKET:
3377             acl_handler(packet, size);
3378             break;
3379 #ifdef ENABLE_CLASSIC
3380         case HCI_SCO_DATA_PACKET:
3381             sco_handler(packet, size);
3382             break;
3383 #endif
3384         default:
3385             break;
3386     }
3387 }
3388 
3389 /**
3390  * @brief Add event packet handler.
3391  */
3392 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
3393     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
3394 }
3395 
3396 
3397 /** Register HCI packet handlers */
3398 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
3399     hci_stack->acl_packet_handler = handler;
3400 }
3401 
3402 #ifdef ENABLE_CLASSIC
3403 /**
3404  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
3405  */
3406 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
3407     hci_stack->sco_packet_handler = handler;
3408 }
3409 #endif
3410 
3411 static void hci_state_reset(void){
3412     // no connections yet
3413     hci_stack->connections = NULL;
3414 
3415     // keep discoverable/connectable as this has been requested by the client(s)
3416     // hci_stack->discoverable = 0;
3417     // hci_stack->connectable = 0;
3418     // hci_stack->bondable = 1;
3419     // hci_stack->own_addr_type = 0;
3420 
3421     // buffer is free
3422     hci_stack->hci_packet_buffer_reserved = false;
3423 
3424     // no pending cmds
3425     hci_stack->decline_reason = 0;
3426 
3427     hci_stack->secure_connections_active = false;
3428 
3429 #ifdef ENABLE_CLASSIC
3430     hci_stack->new_page_scan_interval = 0xffff;
3431     hci_stack->new_page_scan_window = 0xffff;
3432     hci_stack->new_page_scan_type = 0xff;
3433     hci_stack->inquiry_lap = GAP_IAC_GENERAL_INQUIRY;
3434     hci_stack->gap_tasks =
3435             GAP_TASK_SET_DEFAULT_LINK_POLICY |
3436             GAP_TASK_SET_CLASS_OF_DEVICE |
3437             GAP_TASK_SET_LOCAL_NAME |
3438             GAP_TASK_SET_EIR_DATA |
3439             GAP_TASK_WRITE_SCAN_ENABLE;
3440 #endif
3441 
3442 #ifdef ENABLE_CLASSIC_PAIRING_OOB
3443     hci_stack->classic_read_local_oob_data = true;
3444     hci_stack->classic_oob_con_handle = HCI_CON_HANDLE_INVALID;
3445 #endif
3446 
3447     // LE
3448 #ifdef ENABLE_BLE
3449     memset(hci_stack->le_random_address, 0, 6);
3450     hci_stack->le_random_address_set = 0;
3451 #endif
3452 #ifdef ENABLE_LE_CENTRAL
3453     hci_stack->le_scanning_active  = false;
3454     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
3455     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
3456     hci_stack->le_whitelist_capacity = 0;
3457 #endif
3458 #ifdef ENABLE_LE_PERIPHERAL
3459     hci_stack->le_advertisements_active = false;
3460     if ((hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_PARAMS_SET) != 0){
3461         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3462     }
3463     if (hci_stack->le_advertisements_data != NULL){
3464         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3465     }
3466 #endif
3467 }
3468 
3469 #ifdef ENABLE_CLASSIC
3470 /**
3471  * @brief Configure Bluetooth hardware control. Has to be called before power on.
3472  */
3473 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
3474     // store and open remote device db
3475     hci_stack->link_key_db = link_key_db;
3476     if (hci_stack->link_key_db) {
3477         hci_stack->link_key_db->open();
3478     }
3479 }
3480 #endif
3481 
3482 void hci_init(const hci_transport_t *transport, const void *config){
3483 
3484 #ifdef HAVE_MALLOC
3485     if (!hci_stack) {
3486         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
3487     }
3488 #else
3489     hci_stack = &hci_stack_static;
3490 #endif
3491     memset(hci_stack, 0, sizeof(hci_stack_t));
3492 
3493     // reference to use transport layer implementation
3494     hci_stack->hci_transport = transport;
3495 
3496     // reference to used config
3497     hci_stack->config = config;
3498 
3499     // setup pointer for outgoing packet buffer
3500     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3501 
3502     // max acl payload size defined in config.h
3503     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3504 
3505     // register packet handlers with transport
3506     transport->register_packet_handler(&packet_handler);
3507 
3508     hci_stack->state = HCI_STATE_OFF;
3509 
3510     // class of device
3511     hci_stack->class_of_device = 0x007a020c; // Smartphone
3512 
3513     // bondable by default
3514     hci_stack->bondable = 1;
3515 
3516 #ifdef ENABLE_CLASSIC
3517     // classic name
3518     hci_stack->local_name = default_classic_name;
3519 
3520     // Master slave policy
3521     hci_stack->master_slave_policy = 1;
3522 
3523     // Allow Role Switch
3524     hci_stack->allow_role_switch = 1;
3525 
3526     // Default / minimum security level = 2
3527     hci_stack->gap_security_level = LEVEL_2;
3528 
3529     // Default Security Mode 4
3530     hci_stack->gap_security_mode = GAP_SECURITY_MODE_4;
3531 
3532     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3533     hci_stack->gap_required_encyrption_key_size = 7;
3534 
3535     // Link Supervision Timeout
3536     hci_stack->link_supervision_timeout = HCI_LINK_SUPERVISION_TIMEOUT_DEFAULT;
3537 
3538 #endif
3539 
3540     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3541     hci_stack->ssp_enable = 1;
3542     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3543     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3544     hci_stack->ssp_auto_accept = 1;
3545 
3546     // Secure Connections: enable (requires support from Controller)
3547     hci_stack->secure_connections_enable = true;
3548 
3549     // voice setting - signed 16 bit pcm data with CVSD over the air
3550     hci_stack->sco_voice_setting = 0x60;
3551 
3552 #ifdef ENABLE_LE_CENTRAL
3553     // connection parameter to use for outgoing connections
3554     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3555     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3556     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3557     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3558     hci_stack->le_connection_latency      = 4;         // 4
3559     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3560     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3561     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3562 
3563     // default LE Scanning
3564     hci_stack->le_scan_type     =   0x1; // active
3565     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3566     hci_stack->le_scan_window   =  0x30; //  30 ms
3567 #endif
3568 
3569 #ifdef ENABLE_LE_PERIPHERAL
3570     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3571 #endif
3572 
3573     // connection parameter range used to answer connection parameter update requests in l2cap
3574     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3575     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3576     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3577     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3578     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3579     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3580 
3581     hci_state_reset();
3582 }
3583 
3584 void hci_deinit(void){
3585 #ifdef HAVE_MALLOC
3586     if (hci_stack) {
3587         free(hci_stack);
3588     }
3589 #endif
3590     hci_stack = NULL;
3591 
3592 #ifdef ENABLE_CLASSIC
3593     disable_l2cap_timeouts = 0;
3594 #endif
3595 }
3596 
3597 /**
3598  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3599  */
3600 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3601     hci_stack->chipset = chipset_driver;
3602 
3603     // reset chipset driver - init is also called on power_up
3604     if (hci_stack->chipset && hci_stack->chipset->init){
3605         hci_stack->chipset->init(hci_stack->config);
3606     }
3607 }
3608 
3609 /**
3610  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3611  */
3612 void hci_set_control(const btstack_control_t *hardware_control){
3613     // references to used control implementation
3614     hci_stack->control = hardware_control;
3615     // init with transport config
3616     hardware_control->init(hci_stack->config);
3617 }
3618 
3619 void hci_close(void){
3620 
3621 #ifdef ENABLE_CLASSIC
3622     // close remote device db
3623     if (hci_stack->link_key_db) {
3624         hci_stack->link_key_db->close();
3625     }
3626 #endif
3627 
3628     btstack_linked_list_iterator_t lit;
3629     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3630     while (btstack_linked_list_iterator_has_next(&lit)){
3631         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3632         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3633         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3634         hci_shutdown_connection(connection);
3635     }
3636 
3637     hci_power_control(HCI_POWER_OFF);
3638 
3639 #ifdef HAVE_MALLOC
3640     free(hci_stack);
3641 #endif
3642     hci_stack = NULL;
3643 }
3644 
3645 #ifdef HAVE_SCO_TRANSPORT
3646 void hci_set_sco_transport(const btstack_sco_transport_t *sco_transport){
3647     hci_stack->sco_transport = sco_transport;
3648     sco_transport->register_packet_handler(&packet_handler);
3649 }
3650 #endif
3651 
3652 #ifdef ENABLE_CLASSIC
3653 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3654     // validate ranage and set
3655     if (encryption_key_size < 7)  return;
3656     if (encryption_key_size > 16) return;
3657     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3658 }
3659 
3660 uint8_t gap_set_security_mode(gap_security_mode_t security_mode){
3661     if ((security_mode == GAP_SECURITY_MODE_4) || (security_mode == GAP_SECURITY_MODE_2)){
3662         hci_stack->gap_security_mode = security_mode;
3663         return ERROR_CODE_SUCCESS;
3664     } else {
3665         return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
3666     }
3667 }
3668 
3669 gap_security_mode_t gap_get_security_mode(void){
3670     return hci_stack->gap_security_mode;
3671 }
3672 
3673 void gap_set_security_level(gap_security_level_t security_level){
3674     hci_stack->gap_security_level = security_level;
3675 }
3676 
3677 gap_security_level_t gap_get_security_level(void){
3678     if (hci_stack->gap_secure_connections_only_mode){
3679         return LEVEL_4;
3680     }
3681     return hci_stack->gap_security_level;
3682 }
3683 
3684 void gap_set_minimal_service_security_level(gap_security_level_t security_level){
3685     hci_stack->gap_minimal_service_security_level = security_level;
3686 }
3687 
3688 void gap_set_secure_connections_only_mode(bool enable){
3689     hci_stack->gap_secure_connections_only_mode = enable;
3690 }
3691 
3692 bool gap_get_secure_connections_only_mode(void){
3693     return hci_stack->gap_secure_connections_only_mode;
3694 }
3695 #endif
3696 
3697 #ifdef ENABLE_CLASSIC
3698 void gap_set_class_of_device(uint32_t class_of_device){
3699     hci_stack->class_of_device = class_of_device;
3700     hci_stack->gap_tasks |= GAP_TASK_SET_CLASS_OF_DEVICE;
3701     hci_run();
3702 }
3703 
3704 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3705     hci_stack->default_link_policy_settings = default_link_policy_settings;
3706     hci_stack->gap_tasks |= GAP_TASK_SET_DEFAULT_LINK_POLICY;
3707     hci_run();
3708 }
3709 
3710 void gap_set_allow_role_switch(bool allow_role_switch){
3711     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3712 }
3713 
3714 uint8_t hci_get_allow_role_switch(void){
3715     return  hci_stack->allow_role_switch;
3716 }
3717 
3718 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3719     hci_stack->link_supervision_timeout = link_supervision_timeout;
3720 }
3721 
3722 void hci_disable_l2cap_timeout_check(void){
3723     disable_l2cap_timeouts = 1;
3724 }
3725 #endif
3726 
3727 #ifndef HAVE_HOST_CONTROLLER_API
3728 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3729 void hci_set_bd_addr(bd_addr_t addr){
3730     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3731     hci_stack->custom_bd_addr_set = 1;
3732 }
3733 #endif
3734 
3735 // State-Module-Driver overview
3736 // state                    module  low-level
3737 // HCI_STATE_OFF             off      close
3738 // HCI_STATE_INITIALIZING,   on       open
3739 // HCI_STATE_WORKING,        on       open
3740 // HCI_STATE_HALTING,        on       open
3741 // HCI_STATE_SLEEPING,    off/sleep   close
3742 // HCI_STATE_FALLING_ASLEEP  on       open
3743 
3744 static int hci_power_control_on(void){
3745 
3746     // power on
3747     int err = 0;
3748     if (hci_stack->control && hci_stack->control->on){
3749         err = (*hci_stack->control->on)();
3750     }
3751     if (err){
3752         log_error( "POWER_ON failed");
3753         hci_emit_hci_open_failed();
3754         return err;
3755     }
3756 
3757     // int chipset driver
3758     if (hci_stack->chipset && hci_stack->chipset->init){
3759         hci_stack->chipset->init(hci_stack->config);
3760     }
3761 
3762     // init transport
3763     if (hci_stack->hci_transport->init){
3764         hci_stack->hci_transport->init(hci_stack->config);
3765     }
3766 
3767     // open transport
3768     err = hci_stack->hci_transport->open();
3769     if (err){
3770         log_error( "HCI_INIT failed, turning Bluetooth off again");
3771         if (hci_stack->control && hci_stack->control->off){
3772             (*hci_stack->control->off)();
3773         }
3774         hci_emit_hci_open_failed();
3775         return err;
3776     }
3777     return 0;
3778 }
3779 
3780 static void hci_power_control_off(void){
3781 
3782     log_info("hci_power_control_off");
3783 
3784     // close low-level device
3785     hci_stack->hci_transport->close();
3786 
3787     log_info("hci_power_control_off - hci_transport closed");
3788 
3789     // power off
3790     if (hci_stack->control && hci_stack->control->off){
3791         (*hci_stack->control->off)();
3792     }
3793 
3794     log_info("hci_power_control_off - control closed");
3795 
3796     hci_stack->state = HCI_STATE_OFF;
3797 }
3798 
3799 static void hci_power_control_sleep(void){
3800 
3801     log_info("hci_power_control_sleep");
3802 
3803 #if 0
3804     // don't close serial port during sleep
3805 
3806     // close low-level device
3807     hci_stack->hci_transport->close(hci_stack->config);
3808 #endif
3809 
3810     // sleep mode
3811     if (hci_stack->control && hci_stack->control->sleep){
3812         (*hci_stack->control->sleep)();
3813     }
3814 
3815     hci_stack->state = HCI_STATE_SLEEPING;
3816 }
3817 
3818 static int hci_power_control_wake(void){
3819 
3820     log_info("hci_power_control_wake");
3821 
3822     // wake on
3823     if (hci_stack->control && hci_stack->control->wake){
3824         (*hci_stack->control->wake)();
3825     }
3826 
3827 #if 0
3828     // open low-level device
3829     int err = hci_stack->hci_transport->open(hci_stack->config);
3830     if (err){
3831         log_error( "HCI_INIT failed, turning Bluetooth off again");
3832         if (hci_stack->control && hci_stack->control->off){
3833             (*hci_stack->control->off)();
3834         }
3835         hci_emit_hci_open_failed();
3836         return err;
3837     }
3838 #endif
3839 
3840     return 0;
3841 }
3842 
3843 static void hci_power_transition_to_initializing(void){
3844     // set up state machine
3845     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3846     hci_stack->hci_packet_buffer_reserved = false;
3847     hci_stack->state = HCI_STATE_INITIALIZING;
3848     hci_stack->substate = HCI_INIT_SEND_RESET;
3849 }
3850 
3851 // returns error
3852 static int hci_power_control_state_off(HCI_POWER_MODE power_mode){
3853     int err;
3854     switch (power_mode){
3855         case HCI_POWER_ON:
3856             err = hci_power_control_on();
3857             if (err != 0) {
3858                 log_error("hci_power_control_on() error %d", err);
3859                 return err;
3860             }
3861             hci_power_transition_to_initializing();
3862             break;
3863         case HCI_POWER_OFF:
3864             // do nothing
3865             break;
3866         case HCI_POWER_SLEEP:
3867             // do nothing (with SLEEP == OFF)
3868             break;
3869         default:
3870             btstack_assert(false);
3871             break;
3872     }
3873     return ERROR_CODE_SUCCESS;
3874 }
3875 
3876 static int hci_power_control_state_initializing(HCI_POWER_MODE power_mode){
3877     switch (power_mode){
3878         case HCI_POWER_ON:
3879             // do nothing
3880             break;
3881         case HCI_POWER_OFF:
3882             // no connections yet, just turn it off
3883             hci_power_control_off();
3884             break;
3885         case HCI_POWER_SLEEP:
3886             // no connections yet, just turn it off
3887             hci_power_control_sleep();
3888             break;
3889         default:
3890             btstack_assert(false);
3891             break;
3892     }
3893     return ERROR_CODE_SUCCESS;
3894 }
3895 
3896 static int hci_power_control_state_working(HCI_POWER_MODE power_mode) {
3897     switch (power_mode){
3898         case HCI_POWER_ON:
3899             // do nothing
3900             break;
3901         case HCI_POWER_OFF:
3902             // see hci_run
3903             hci_stack->state = HCI_STATE_HALTING;
3904             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3905             break;
3906         case HCI_POWER_SLEEP:
3907             // see hci_run
3908             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3909             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3910             break;
3911         default:
3912             btstack_assert(false);
3913             break;
3914     }
3915     return ERROR_CODE_SUCCESS;
3916 }
3917 
3918 static int hci_power_control_state_halting(HCI_POWER_MODE power_mode) {
3919     switch (power_mode){
3920         case HCI_POWER_ON:
3921             hci_power_transition_to_initializing();
3922             break;
3923         case HCI_POWER_OFF:
3924             // do nothing
3925             break;
3926         case HCI_POWER_SLEEP:
3927             // see hci_run
3928             hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3929             hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3930             break;
3931         default:
3932             btstack_assert(false);
3933             break;
3934     }
3935     return ERROR_CODE_SUCCESS;
3936 }
3937 
3938 static int hci_power_control_state_falling_asleep(HCI_POWER_MODE power_mode) {
3939     switch (power_mode){
3940         case HCI_POWER_ON:
3941             hci_power_transition_to_initializing();
3942             break;
3943         case HCI_POWER_OFF:
3944             // see hci_run
3945             hci_stack->state = HCI_STATE_HALTING;
3946             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3947             break;
3948         case HCI_POWER_SLEEP:
3949             // do nothing
3950             break;
3951         default:
3952             btstack_assert(false);
3953             break;
3954     }
3955     return ERROR_CODE_SUCCESS;
3956 }
3957 
3958 static int hci_power_control_state_sleeping(HCI_POWER_MODE power_mode) {
3959     int err;
3960     switch (power_mode){
3961         case HCI_POWER_ON:
3962             err = hci_power_control_wake();
3963             if (err) return err;
3964             hci_power_transition_to_initializing();
3965             break;
3966         case HCI_POWER_OFF:
3967             hci_stack->state = HCI_STATE_HALTING;
3968             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3969             break;
3970         case HCI_POWER_SLEEP:
3971             // do nothing
3972             break;
3973         default:
3974             btstack_assert(false);
3975             break;
3976     }
3977     return ERROR_CODE_SUCCESS;
3978 }
3979 
3980 int hci_power_control(HCI_POWER_MODE power_mode){
3981     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3982     int err = 0;
3983     switch (hci_stack->state){
3984         case HCI_STATE_OFF:
3985             err = hci_power_control_state_off(power_mode);
3986             break;
3987         case HCI_STATE_INITIALIZING:
3988             err = hci_power_control_state_initializing(power_mode);
3989             break;
3990         case HCI_STATE_WORKING:
3991             err = hci_power_control_state_working(power_mode);
3992             break;
3993         case HCI_STATE_HALTING:
3994             err = hci_power_control_state_halting(power_mode);
3995             break;
3996         case HCI_STATE_FALLING_ASLEEP:
3997             err = hci_power_control_state_falling_asleep(power_mode);
3998             break;
3999         case HCI_STATE_SLEEPING:
4000             err = hci_power_control_state_sleeping(power_mode);
4001             break;
4002         default:
4003             btstack_assert(false);
4004             break;
4005     }
4006     if (err != 0){
4007         return err;
4008     }
4009 
4010     // create internal event
4011 	hci_emit_state();
4012 
4013 	// trigger next/first action
4014 	hci_run();
4015 
4016     return 0;
4017 }
4018 
4019 
4020 #ifdef ENABLE_CLASSIC
4021 
4022 static void hci_update_scan_enable(void){
4023     // 2 = page scan, 1 = inq scan
4024     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
4025     hci_stack->gap_tasks |= GAP_TASK_WRITE_SCAN_ENABLE;
4026     hci_run();
4027 }
4028 
4029 void gap_discoverable_control(uint8_t enable){
4030     if (enable) enable = 1; // normalize argument
4031 
4032     if (hci_stack->discoverable == enable){
4033         hci_emit_discoverable_enabled(hci_stack->discoverable);
4034         return;
4035     }
4036 
4037     hci_stack->discoverable = enable;
4038     hci_update_scan_enable();
4039 }
4040 
4041 void gap_connectable_control(uint8_t enable){
4042     if (enable) enable = 1; // normalize argument
4043 
4044     // don't emit event
4045     if (hci_stack->connectable == enable) return;
4046 
4047     hci_stack->connectable = enable;
4048     hci_update_scan_enable();
4049 }
4050 #endif
4051 
4052 void gap_local_bd_addr(bd_addr_t address_buffer){
4053     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
4054 }
4055 
4056 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4057 static void hci_host_num_completed_packets(void){
4058 
4059     // create packet manually as arrays are not supported and num_commands should not get reduced
4060     hci_reserve_packet_buffer();
4061     uint8_t * packet = hci_get_outgoing_packet_buffer();
4062 
4063     uint16_t size = 0;
4064     uint16_t num_handles = 0;
4065     packet[size++] = 0x35;
4066     packet[size++] = 0x0c;
4067     size++;  // skip param len
4068     size++;  // skip num handles
4069 
4070     // add { handle, packets } entries
4071     btstack_linked_item_t * it;
4072     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
4073         hci_connection_t * connection = (hci_connection_t *) it;
4074         if (connection->num_packets_completed){
4075             little_endian_store_16(packet, size, connection->con_handle);
4076             size += 2;
4077             little_endian_store_16(packet, size, connection->num_packets_completed);
4078             size += 2;
4079             //
4080             num_handles++;
4081             connection->num_packets_completed = 0;
4082         }
4083     }
4084 
4085     packet[2] = size - 3;
4086     packet[3] = num_handles;
4087 
4088     hci_stack->host_completed_packets = 0;
4089 
4090     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4091     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4092 
4093     // release packet buffer for synchronous transport implementations
4094     if (hci_transport_synchronous()){
4095         hci_release_packet_buffer();
4096         hci_emit_transport_packet_sent();
4097     }
4098 }
4099 #endif
4100 
4101 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
4102     UNUSED(ds);
4103     hci_stack->substate = HCI_HALTING_CLOSE;
4104     // allow packet handlers to defer final shutdown
4105     hci_emit_state();
4106     hci_run();
4107 }
4108 
4109 static bool hci_run_acl_fragments(void){
4110     if (hci_stack->acl_fragmentation_total_size > 0u) {
4111         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
4112         hci_connection_t *connection = hci_connection_for_handle(con_handle);
4113         if (connection) {
4114             if (hci_can_send_prepared_acl_packet_now(con_handle)){
4115                 hci_send_acl_packet_fragments(connection);
4116                 return true;
4117             }
4118         } else {
4119             // connection gone -> discard further fragments
4120             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
4121             hci_stack->acl_fragmentation_total_size = 0;
4122             hci_stack->acl_fragmentation_pos = 0;
4123         }
4124     }
4125     return false;
4126 }
4127 
4128 #ifdef ENABLE_CLASSIC
4129 static bool hci_run_general_gap_classic(void){
4130 
4131     // assert stack is working and classic is active
4132     if (hci_classic_supported() == false)      return false;
4133     if (hci_stack->state != HCI_STATE_WORKING) return false;
4134 
4135     // decline incoming connections
4136     if (hci_stack->decline_reason){
4137         uint8_t reason = hci_stack->decline_reason;
4138         hci_stack->decline_reason = 0;
4139         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
4140         return true;
4141     }
4142 
4143     if ((hci_stack->gap_tasks & GAP_TASK_SET_CLASS_OF_DEVICE) != 0) {
4144         hci_stack->gap_tasks &= ~GAP_TASK_SET_CLASS_OF_DEVICE;
4145         hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
4146         return true;
4147     }
4148     if ((hci_stack->gap_tasks & GAP_TASK_SET_LOCAL_NAME) != 0) {
4149         hci_stack->gap_tasks &= ~GAP_TASK_SET_LOCAL_NAME;
4150         gap_run_set_local_name();
4151         return true;
4152     }
4153     if ((hci_stack->gap_tasks & GAP_TASK_SET_EIR_DATA) != 0) {
4154         hci_stack->gap_tasks &= ~GAP_TASK_SET_EIR_DATA;
4155         gap_run_set_eir_data();
4156         return true;
4157     }
4158     if ((hci_stack->gap_tasks & GAP_TASK_SET_DEFAULT_LINK_POLICY) != 0) {
4159         hci_stack->gap_tasks &= ~GAP_TASK_SET_DEFAULT_LINK_POLICY;
4160         hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
4161         return true;
4162     }
4163     // write page scan activity
4164     if (hci_stack->new_page_scan_interval != 0xffff) {
4165         uint16_t new_page_scan_interval = hci_stack->new_page_scan_interval;
4166         uint16_t new_page_scan_window = hci_stack->new_page_scan_window;
4167         hci_stack->new_page_scan_interval = 0xffff;
4168         hci_stack->new_page_scan_window = 0xffff;
4169         hci_send_cmd(&hci_write_page_scan_activity, new_page_scan_interval, new_page_scan_window);
4170         return true;
4171     }
4172     // write page scan type
4173     if (hci_stack->new_page_scan_type != 0xff) {
4174         uint8_t new_page_scan_type = hci_stack->new_page_scan_type;
4175         hci_stack->new_page_scan_type = 0xff;
4176         hci_send_cmd(&hci_write_page_scan_type, new_page_scan_type);
4177         return true;
4178     }
4179     // send scan enable
4180     if ((hci_stack->gap_tasks & GAP_TASK_WRITE_SCAN_ENABLE) != 0) {
4181         hci_stack->gap_tasks &= ~GAP_TASK_WRITE_SCAN_ENABLE;
4182         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
4183         return true;
4184     }
4185     // start/stop inquiry
4186     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
4187         uint8_t duration = hci_stack->inquiry_state;
4188         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_ACTIVE;
4189         hci_send_cmd(&hci_inquiry, hci_stack->inquiry_lap, duration, 0);
4190         return true;
4191     }
4192     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
4193         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
4194         hci_send_cmd(&hci_inquiry_cancel);
4195         return true;
4196     }
4197     // remote name request
4198     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
4199         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
4200         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
4201                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
4202         return true;
4203     }
4204 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4205     // Local OOB data
4206     if (hci_stack->classic_read_local_oob_data){
4207         hci_stack->classic_read_local_oob_data = false;
4208         if (hci_stack->local_supported_commands[1] & 0x10u){
4209             hci_send_cmd(&hci_read_local_extended_oob_data);
4210         } else {
4211             hci_send_cmd(&hci_read_local_oob_data);
4212         }
4213     }
4214 #endif
4215     // pairing
4216     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
4217         uint8_t state = hci_stack->gap_pairing_state;
4218         uint8_t pin_code[16];
4219         switch (state){
4220             case GAP_PAIRING_STATE_SEND_PIN:
4221                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4222                 memset(pin_code, 0, 16);
4223                 memcpy(pin_code, hci_stack->gap_pairing_input.gap_pairing_pin, hci_stack->gap_pairing_pin_len);
4224                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, pin_code);
4225                 break;
4226             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
4227                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4228                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
4229                 break;
4230             case GAP_PAIRING_STATE_SEND_PASSKEY:
4231                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4232                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
4233                 break;
4234             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
4235                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4236                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
4237                 break;
4238             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
4239                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
4240                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
4241                 break;
4242             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
4243                 hci_stack->gap_pairing_state = GAP_PAIRING_STATE_WAIT_FOR_COMMAND_COMPLETE;
4244                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
4245                 break;
4246             default:
4247                 break;
4248         }
4249         return true;
4250     }
4251     return false;
4252 }
4253 #endif
4254 
4255 #ifdef ENABLE_BLE
4256 static bool hci_run_general_gap_le(void){
4257 
4258     // advertisements, active scanning, and creating connections requires random address to be set if using private address
4259 
4260     if (hci_stack->state != HCI_STATE_WORKING) return false;
4261     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
4262 
4263 
4264     // Phase 1: collect what to stop
4265 
4266     bool scanning_stop = false;
4267     bool connecting_stop = false;
4268     bool advertising_stop = false;
4269 
4270 #ifndef ENABLE_LE_CENTRAL
4271     UNUSED(scanning_stop);
4272     UNUSED(connecting_stop);
4273 #endif
4274 #ifndef ENABLE_LE_PERIPHERAL
4275     UNUSED(advertising_stop);
4276 #endif
4277 
4278     // check if whitelist needs modification
4279     bool whitelist_modification_pending = false;
4280     btstack_linked_list_iterator_t lit;
4281     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4282     while (btstack_linked_list_iterator_has_next(&lit)){
4283         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4284         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
4285             whitelist_modification_pending = true;
4286             break;
4287         }
4288     }
4289     // check if resolving list needs modification
4290     bool resolving_list_modification_pending = false;
4291 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4292     bool resolving_list_supported = (hci_stack->local_supported_commands[1] & (1 << 2)) != 0;
4293 	if (resolving_list_supported && hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_DONE){
4294         resolving_list_modification_pending = true;
4295     }
4296 #endif
4297 
4298 #ifdef ENABLE_LE_CENTRAL
4299     // scanning control
4300     if (hci_stack->le_scanning_active) {
4301         // stop if:
4302         // - parameter change required
4303         // - it's disabled
4304         // - whitelist change required but used for scanning
4305         // - resolving list modified
4306         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
4307         if ((hci_stack->le_scanning_param_update) ||
4308             !hci_stack->le_scanning_enabled ||
4309             scanning_uses_whitelist ||
4310             resolving_list_modification_pending){
4311 
4312             scanning_stop = true;
4313         }
4314     }
4315 #endif
4316 
4317 #ifdef ENABLE_LE_CENTRAL
4318     // connecting control
4319     bool connecting_with_whitelist;
4320     switch (hci_stack->le_connecting_state){
4321         case LE_CONNECTING_DIRECT:
4322         case LE_CONNECTING_WHITELIST:
4323             // stop connecting if:
4324             // - connecting uses white and whitelist modification pending
4325             // - if it got disabled
4326             // - resolving list modified
4327             connecting_with_whitelist = hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST;
4328             if ((connecting_with_whitelist && whitelist_modification_pending) ||
4329                 (hci_stack->le_connecting_request == LE_CONNECTING_IDLE) ||
4330                 resolving_list_modification_pending) {
4331 
4332                 connecting_stop = true;
4333             }
4334             break;
4335         default:
4336             break;
4337     }
4338 #endif
4339 
4340 #ifdef ENABLE_LE_PERIPHERAL
4341     // le advertisement control
4342     if (hci_stack->le_advertisements_active){
4343         // stop if:
4344         // - parameter change required
4345         // - it's disabled
4346         // - whitelist change required but used for advertisement filter policy
4347         // - resolving list modified
4348         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy != 0;
4349         bool advertising_change = (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS) != 0;
4350         if (advertising_change ||
4351             (hci_stack->le_advertisements_enabled_for_current_roles == 0) ||
4352             (advertising_uses_whitelist & whitelist_modification_pending) ||
4353             resolving_list_modification_pending) {
4354 
4355             advertising_stop = true;
4356         }
4357     }
4358 #endif
4359 
4360 
4361     // Phase 2: stop everything that should be off during modifications
4362 
4363 #ifdef ENABLE_LE_CENTRAL
4364     if (scanning_stop){
4365         hci_stack->le_scanning_active = false;
4366         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
4367         return true;
4368     }
4369 #endif
4370 
4371 #ifdef ENABLE_LE_CENTRAL
4372     if (connecting_stop){
4373         hci_send_cmd(&hci_le_create_connection_cancel);
4374         return true;
4375     }
4376 #endif
4377 
4378 #ifdef ENABLE_LE_PERIPHERAL
4379     if (advertising_stop){
4380         hci_stack->le_advertisements_active = false;
4381         hci_send_cmd(&hci_le_set_advertise_enable, 0);
4382         return true;
4383     }
4384 #endif
4385 
4386     // Phase 3: modify
4387 
4388 #ifdef ENABLE_LE_CENTRAL
4389     if (hci_stack->le_scanning_param_update){
4390         hci_stack->le_scanning_param_update = false;
4391         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
4392                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
4393         return true;
4394     }
4395 #endif
4396 
4397 #ifdef ENABLE_LE_PERIPHERAL
4398     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
4399         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4400         hci_stack->le_advertisements_own_addr_type = hci_stack->le_own_addr_type;
4401         hci_send_cmd(&hci_le_set_advertising_parameters,
4402                      hci_stack->le_advertisements_interval_min,
4403                      hci_stack->le_advertisements_interval_max,
4404                      hci_stack->le_advertisements_type,
4405                      hci_stack->le_advertisements_own_addr_type,
4406                      hci_stack->le_advertisements_direct_address_type,
4407                      hci_stack->le_advertisements_direct_address,
4408                      hci_stack->le_advertisements_channel_map,
4409                      hci_stack->le_advertisements_filter_policy);
4410         return true;
4411     }
4412     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
4413         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4414         uint8_t adv_data_clean[31];
4415         memset(adv_data_clean, 0, sizeof(adv_data_clean));
4416         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
4417                      hci_stack->le_advertisements_data_len);
4418         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
4419         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
4420         return true;
4421     }
4422     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
4423         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4424         uint8_t scan_data_clean[31];
4425         memset(scan_data_clean, 0, sizeof(scan_data_clean));
4426         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
4427                      hci_stack->le_scan_response_data_len);
4428         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
4429         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
4430         return true;
4431     }
4432 #endif
4433 
4434 
4435 #ifdef ENABLE_LE_CENTRAL
4436     // if connect with whitelist was active and is not cancelled yet, wait until next time
4437     if (hci_stack->le_connecting_state == LE_CONNECTING_CANCEL) return false;
4438 #endif
4439 
4440     // LE Whitelist Management
4441     if (whitelist_modification_pending){
4442         // add/remove entries
4443         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4444         while (btstack_linked_list_iterator_has_next(&lit)){
4445             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4446 			if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
4447 				entry->state &= ~LE_WHITELIST_REMOVE_FROM_CONTROLLER;
4448 				hci_send_cmd(&hci_le_remove_device_from_white_list, entry->address_type, entry->address);
4449 				return true;
4450 			}
4451             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
4452 				entry->state &= ~LE_WHITELIST_ADD_TO_CONTROLLER;
4453                 entry->state |= LE_WHITELIST_ON_CONTROLLER;
4454                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
4455                 return true;
4456             }
4457             if ((entry->state & LE_WHITELIST_ON_CONTROLLER) == 0){
4458 				btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4459 				btstack_memory_whitelist_entry_free(entry);
4460             }
4461         }
4462     }
4463 
4464 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
4465     // LE Resolving List Management
4466     if (resolving_list_supported) {
4467 		uint16_t i;
4468 		switch (hci_stack->le_resolving_list_state) {
4469 			case LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION:
4470 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
4471 				hci_send_cmd(&hci_le_set_address_resolution_enabled, 1);
4472 				return true;
4473 			case LE_RESOLVING_LIST_READ_SIZE:
4474 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_SEND_CLEAR;
4475 				hci_send_cmd(&hci_le_read_resolving_list_size);
4476 				return true;
4477 			case LE_RESOLVING_LIST_SEND_CLEAR:
4478 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
4479 				(void) memset(hci_stack->le_resolving_list_add_entries, 0xff,
4480 							  sizeof(hci_stack->le_resolving_list_add_entries));
4481 				(void) memset(hci_stack->le_resolving_list_remove_entries, 0,
4482 							  sizeof(hci_stack->le_resolving_list_remove_entries));
4483 				hci_send_cmd(&hci_le_clear_resolving_list);
4484 				return true;
4485 			case LE_RESOLVING_LIST_REMOVE_ENTRIES:
4486 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4487 					uint8_t offset = i >> 3;
4488 					uint8_t mask = 1 << (i & 7);
4489 					if ((hci_stack->le_resolving_list_remove_entries[offset] & mask) == 0) continue;
4490 					hci_stack->le_resolving_list_remove_entries[offset] &= ~mask;
4491 					bd_addr_t peer_identity_addreses;
4492 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4493 					sm_key_t peer_irk;
4494 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4495 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4496 
4497 #ifdef ENABLE_LE_WHITELIST_TOUCH_AFTER_RESOLVING_LIST_UPDATE
4498 					// trigger whitelist entry 'update' (work around for controller bug)
4499 					btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4500 					while (btstack_linked_list_iterator_has_next(&lit)) {
4501 						whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&lit);
4502 						if (entry->address_type != peer_identity_addr_type) continue;
4503 						if (memcmp(entry->address, peer_identity_addreses, 6) != 0) continue;
4504 						log_info("trigger whitelist update %s", bd_addr_to_str(peer_identity_addreses));
4505 						entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER;
4506 					}
4507 #endif
4508 
4509 					hci_send_cmd(&hci_le_remove_device_from_resolving_list, peer_identity_addr_type,
4510 								 peer_identity_addreses);
4511 					return true;
4512 				}
4513 
4514 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_ADD_ENTRIES;
4515 
4516 				/* fall through */
4517 
4518 			case LE_RESOLVING_LIST_ADD_ENTRIES:
4519 				for (i = 0; i < MAX_NUM_RESOLVING_LIST_ENTRIES && i < le_device_db_max_count(); i++) {
4520 					uint8_t offset = i >> 3;
4521 					uint8_t mask = 1 << (i & 7);
4522 					if ((hci_stack->le_resolving_list_add_entries[offset] & mask) == 0) continue;
4523 					hci_stack->le_resolving_list_add_entries[offset] &= ~mask;
4524 					bd_addr_t peer_identity_addreses;
4525 					int peer_identity_addr_type = (int) BD_ADDR_TYPE_UNKNOWN;
4526 					sm_key_t peer_irk;
4527 					le_device_db_info(i, &peer_identity_addr_type, peer_identity_addreses, peer_irk);
4528 					if (peer_identity_addr_type == BD_ADDR_TYPE_UNKNOWN) continue;
4529 					const uint8_t *local_irk = gap_get_persistent_irk();
4530 					// command uses format specifier 'P' that stores 16-byte value without flip
4531 					uint8_t local_irk_flipped[16];
4532 					uint8_t peer_irk_flipped[16];
4533 					reverse_128(local_irk, local_irk_flipped);
4534 					reverse_128(peer_irk, peer_irk_flipped);
4535 					hci_send_cmd(&hci_le_add_device_to_resolving_list, peer_identity_addr_type, peer_identity_addreses,
4536 								 peer_irk_flipped, local_irk_flipped);
4537 					return true;
4538 				}
4539 				hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4540 				break;
4541 
4542 			default:
4543 				break;
4544 		}
4545 	}
4546     hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_DONE;
4547 #endif
4548 
4549     // Phase 4: restore state
4550 
4551 #ifdef ENABLE_LE_CENTRAL
4552     // re-start scanning
4553     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
4554         hci_stack->le_scanning_active = true;
4555         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
4556         return true;
4557     }
4558 #endif
4559 
4560 #ifdef ENABLE_LE_CENTRAL
4561     // re-start connecting
4562     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
4563         bd_addr_t null_addr;
4564         memset(null_addr, 0, 6);
4565         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4566         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4567         hci_send_cmd(&hci_le_create_connection,
4568                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
4569                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
4570                      1,         // use whitelist
4571                      0,         // peer address type
4572                      null_addr, // peer bd addr
4573                      hci_stack->le_connection_own_addr_type,   // our addr type:
4574                      hci_stack->le_connection_interval_min,    // conn interval min
4575                      hci_stack->le_connection_interval_max,    // conn interval max
4576                      hci_stack->le_connection_latency,         // conn latency
4577                      hci_stack->le_supervision_timeout,        // conn latency
4578                      hci_stack->le_minimum_ce_length,          // min ce length
4579                      hci_stack->le_maximum_ce_length           // max ce length
4580         );
4581         return true;
4582     }
4583 #endif
4584 
4585 #ifdef ENABLE_LE_PERIPHERAL
4586     // re-start advertising
4587     if (hci_stack->le_advertisements_enabled_for_current_roles && !hci_stack->le_advertisements_active){
4588         // check if advertisements should be enabled given
4589         hci_stack->le_advertisements_active = true;
4590         hci_get_own_address_for_addr_type(hci_stack->le_advertisements_own_addr_type, hci_stack->le_advertisements_own_address);
4591         hci_send_cmd(&hci_le_set_advertise_enable, 1);
4592         return true;
4593     }
4594 #endif
4595 
4596     return false;
4597 }
4598 #endif
4599 
4600 static bool hci_run_general_pending_commands(void){
4601     btstack_linked_item_t * it;
4602     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4603         hci_connection_t * connection = (hci_connection_t *) it;
4604 
4605         switch(connection->state){
4606             case SEND_CREATE_CONNECTION:
4607                 switch(connection->address_type){
4608 #ifdef ENABLE_CLASSIC
4609                     case BD_ADDR_TYPE_ACL:
4610                         log_info("sending hci_create_connection");
4611                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
4612                         break;
4613 #endif
4614                     default:
4615 #ifdef ENABLE_BLE
4616 #ifdef ENABLE_LE_CENTRAL
4617                         log_info("sending hci_le_create_connection");
4618                         hci_stack->le_connection_own_addr_type =  hci_stack->le_own_addr_type;
4619                         hci_get_own_address_for_addr_type(hci_stack->le_connection_own_addr_type, hci_stack->le_connection_own_address);
4620                         hci_send_cmd(&hci_le_create_connection,
4621                                      hci_stack->le_connection_scan_interval,    // conn scan interval
4622                                      hci_stack->le_connection_scan_window,      // conn scan windows
4623                                      0,         // don't use whitelist
4624                                      connection->address_type, // peer address type
4625                                      connection->address,      // peer bd addr
4626                                      hci_stack->le_connection_own_addr_type,   // our addr type:
4627                                      hci_stack->le_connection_interval_min,    // conn interval min
4628                                      hci_stack->le_connection_interval_max,    // conn interval max
4629                                      hci_stack->le_connection_latency,         // conn latency
4630                                      hci_stack->le_supervision_timeout,        // conn latency
4631                                      hci_stack->le_minimum_ce_length,          // min ce length
4632                                      hci_stack->le_maximum_ce_length          // max ce length
4633                         );
4634                         connection->state = SENT_CREATE_CONNECTION;
4635 #endif
4636 #endif
4637                         break;
4638                 }
4639                 return true;
4640 
4641 #ifdef ENABLE_CLASSIC
4642             case RECEIVED_CONNECTION_REQUEST:
4643                 connection->role  = HCI_ROLE_SLAVE;
4644                 if (connection->address_type == BD_ADDR_TYPE_ACL){
4645                     log_info("sending hci_accept_connection_request");
4646                     connection->state = ACCEPTED_CONNECTION_REQUEST;
4647                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
4648                 }
4649                 return true;
4650 #endif
4651 
4652 #ifdef ENABLE_BLE
4653 #ifdef ENABLE_LE_CENTRAL
4654             case SEND_CANCEL_CONNECTION:
4655                 connection->state = SENT_CANCEL_CONNECTION;
4656                 hci_send_cmd(&hci_le_create_connection_cancel);
4657                 return true;
4658 #endif
4659 #endif
4660             case SEND_DISCONNECT:
4661                 connection->state = SENT_DISCONNECT;
4662                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4663                 return true;
4664 
4665             default:
4666                 break;
4667         }
4668 
4669         // no further commands if connection is about to get shut down
4670         if (connection->state == SENT_DISCONNECT) continue;
4671 
4672         if (connection->authentication_flags & AUTH_FLAG_READ_RSSI){
4673             connectionClearAuthenticationFlags(connection, AUTH_FLAG_READ_RSSI);
4674             hci_send_cmd(&hci_read_rssi, connection->con_handle);
4675             return true;
4676         }
4677 
4678 #ifdef ENABLE_CLASSIC
4679 
4680         if (connection->authentication_flags & AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT){
4681             connectionClearAuthenticationFlags(connection, AUTH_FLAG_WRITE_SUPERVISION_TIMEOUT);
4682             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
4683             return true;
4684         }
4685 
4686         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
4687             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
4688             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
4689             return true;
4690         }
4691 
4692         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
4693             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
4694             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
4695             return true;
4696         }
4697 
4698         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
4699             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
4700             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
4701             return true;
4702         }
4703 
4704         // Handling link key request requires remote supported features
4705         if (((connection->authentication_flags & AUTH_FLAG_HANDLE_LINK_KEY_REQUEST) != 0)){
4706             log_info("responding to link key request, have link key db: %u", hci_stack->link_key_db != NULL);
4707             connectionClearAuthenticationFlags(connection, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
4708 
4709             bool have_link_key = connection->link_key_type != INVALID_LINK_KEY;
4710             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(connection->link_key_type) >= connection->requested_security_level);
4711             if (have_link_key && security_level_sufficient){
4712                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &connection->link_key);
4713             } else {
4714                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
4715             }
4716             return true;
4717         }
4718 
4719         if (connection->authentication_flags & AUTH_FLAG_DENY_PIN_CODE_REQUEST){
4720             log_info("denying to pin request");
4721             connectionClearAuthenticationFlags(connection, AUTH_FLAG_DENY_PIN_CODE_REQUEST);
4722             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
4723             return true;
4724         }
4725 
4726         // security assessment requires remote features
4727         if ((connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST) != 0){
4728             connectionClearAuthenticationFlags(connection, AUTH_FLAG_RECV_IO_CAPABILITIES_REQUEST);
4729             hci_ssp_assess_security_on_io_cap_request(connection);
4730             // 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
4731         }
4732 
4733         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY){
4734             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
4735             // set authentication requirements:
4736             // - MITM = ssp_authentication_requirement (USER) | requested_security_level (dynamic)
4737             // - BONDING MODE: dedicated if requested, bondable otherwise. Drop bondable if not set for remote
4738             uint8_t authreq = hci_stack->ssp_authentication_requirement & 1;
4739             if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
4740                 authreq |= 1;
4741             }
4742             bool bonding = hci_stack->bondable;
4743             if (connection->authentication_flags & AUTH_FLAG_RECV_IO_CAPABILITIES_RESPONSE){
4744                 // if we have received IO Cap Response, we're in responder role
4745                 bool remote_bonding = connection->io_cap_response_auth_req >= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4746                 if (bonding && !remote_bonding){
4747                     log_info("Remote not bonding, dropping local flag");
4748                     bonding = false;
4749                 }
4750             }
4751             if (bonding){
4752                 if (connection->bonding_flags & BONDING_DEDICATED){
4753                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
4754                 } else {
4755                     authreq |= SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
4756                 }
4757             }
4758             uint8_t have_oob_data = 0;
4759 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4760             if (connection->classic_oob_c_192 != NULL){
4761                     have_oob_data |= 1;
4762             }
4763             if (connection->classic_oob_c_256 != NULL){
4764                 have_oob_data |= 2;
4765             }
4766 #endif
4767             hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, have_oob_data, authreq);
4768             return true;
4769         }
4770 
4771         if (connection->authentication_flags & AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY) {
4772             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
4773             hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
4774             return true;
4775         }
4776 
4777 #ifdef ENABLE_CLASSIC_PAIRING_OOB
4778         if (connection->authentication_flags & AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY){
4779             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_REMOTE_OOB_DATA_REPLY);
4780             const uint8_t zero[16] = { 0 };
4781             const uint8_t * r_192 = zero;
4782             const uint8_t * c_192 = zero;
4783             const uint8_t * r_256 = zero;
4784             const uint8_t * c_256 = zero;
4785             // verify P-256 OOB
4786             if ((connection->classic_oob_c_256 != NULL) && ((hci_stack->local_supported_commands[1] & 0x08u) != 0)) {
4787                 c_256 = connection->classic_oob_c_256;
4788                 if (connection->classic_oob_r_256 != NULL) {
4789                     r_256 = connection->classic_oob_r_256;
4790                 }
4791             }
4792             // verify P-192 OOB
4793             if ((connection->classic_oob_c_192 != NULL)) {
4794                 c_192 = connection->classic_oob_c_192;
4795                 if (connection->classic_oob_r_192 != NULL) {
4796                     r_192 = connection->classic_oob_r_192;
4797                 }
4798             }
4799 
4800             // assess security
4801             bool need_level_4 = hci_stack->gap_secure_connections_only_mode || (connection->requested_security_level == LEVEL_4);
4802             bool can_reach_level_4 = hci_remote_sc_enabled(connection) && (c_256 != NULL);
4803             if (need_level_4 && !can_reach_level_4){
4804                 log_info("Level 4 required, but not possible -> abort");
4805                 hci_pairing_complete(connection, ERROR_CODE_INSUFFICIENT_SECURITY);
4806                 // send oob negative reply
4807                 c_256 = NULL;
4808                 c_192 = NULL;
4809             }
4810 
4811             // Reply
4812             if (c_256 != zero) {
4813                 hci_send_cmd(&hci_remote_oob_extended_data_request_reply, &connection->address, c_192, r_192, c_256, r_256);
4814             } else if (c_192 != zero){
4815                 hci_send_cmd(&hci_remote_oob_data_request_reply, &connection->address, c_192, r_192);
4816             } else {
4817                 hci_stack->classic_oob_con_handle = connection->con_handle;
4818                 hci_send_cmd(&hci_remote_oob_data_request_negative_reply, &connection->address);
4819             }
4820             return true;
4821         }
4822 #endif
4823 
4824         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_REPLY){
4825             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_REPLY);
4826             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
4827             return true;
4828         }
4829 
4830         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY){
4831             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_CONFIRM_NEGATIVE_REPLY);
4832             hci_send_cmd(&hci_user_confirmation_request_negative_reply, &connection->address);
4833             return true;
4834         }
4835 
4836         if (connection->authentication_flags & AUTH_FLAG_SEND_USER_PASSKEY_REPLY){
4837             connectionClearAuthenticationFlags(connection, AUTH_FLAG_SEND_USER_PASSKEY_REPLY);
4838             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
4839             return true;
4840         }
4841 
4842         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
4843             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
4844             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
4845             connection->state = SENT_DISCONNECT;
4846             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4847             return true;
4848         }
4849 
4850         if ((connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST) && ((connection->bonding_flags & BONDING_RECEIVED_REMOTE_FEATURES) != 0)){
4851             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
4852             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
4853             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
4854             return true;
4855         }
4856 
4857         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
4858             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
4859             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
4860             return true;
4861         }
4862         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
4863             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
4864             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
4865             return true;
4866         }
4867 #endif
4868 
4869         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
4870             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
4871 #ifdef ENABLE_CLASSIC
4872             hci_pairing_complete(connection, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_SECURITY_REASONS);
4873 #endif
4874             if (connection->state != SENT_DISCONNECT){
4875                 connection->state = SENT_DISCONNECT;
4876                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
4877                 return true;
4878             }
4879         }
4880 
4881 #ifdef ENABLE_CLASSIC
4882         uint16_t sniff_min_interval;
4883         switch (connection->sniff_min_interval){
4884             case 0:
4885                 break;
4886             case 0xffff:
4887                 connection->sniff_min_interval = 0;
4888                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4889                 return true;
4890             default:
4891                 sniff_min_interval = connection->sniff_min_interval;
4892                 connection->sniff_min_interval = 0;
4893                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4894                 return true;
4895         }
4896 
4897         if (connection->sniff_subrating_max_latency != 0xffff){
4898             uint16_t max_latency = connection->sniff_subrating_max_latency;
4899             connection->sniff_subrating_max_latency = 0;
4900             hci_send_cmd(&hci_sniff_subrating, connection->con_handle, max_latency, connection->sniff_subrating_min_remote_timeout, connection->sniff_subrating_min_local_timeout);
4901             return true;
4902         }
4903 
4904         if (connection->qos_service_type != HCI_SERVICE_TYPE_INVALID){
4905             uint8_t service_type = (uint8_t) connection->qos_service_type;
4906             connection->qos_service_type = HCI_SERVICE_TYPE_INVALID;
4907             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);
4908             return true;
4909         }
4910 
4911         if (connection->request_role != HCI_ROLE_INVALID){
4912             hci_role_t role = connection->request_role;
4913             connection->request_role = HCI_ROLE_INVALID;
4914             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4915             return true;
4916         }
4917 #endif
4918 
4919 #ifdef ENABLE_BLE
4920         switch (connection->le_con_parameter_update_state){
4921             // response to L2CAP CON PARAMETER UPDATE REQUEST
4922             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4923                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4924                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4925                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4926                              0x0000, 0xffff);
4927                 return true;
4928             case CON_PARAMETER_UPDATE_REPLY:
4929                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4930                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4931                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4932                              0x0000, 0xffff);
4933                 return true;
4934             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4935                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4936                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4937                 return true;
4938             default:
4939                 break;
4940         }
4941         if (connection->le_phy_update_all_phys != 0xffu){
4942             uint8_t all_phys = connection->le_phy_update_all_phys;
4943             connection->le_phy_update_all_phys = 0xff;
4944             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);
4945             return true;
4946         }
4947 #endif
4948     }
4949     return false;
4950 }
4951 
4952 static void hci_run(void){
4953 
4954     bool done;
4955 
4956     // send continuation fragments first, as they block the prepared packet buffer
4957     done = hci_run_acl_fragments();
4958     if (done) return;
4959 
4960 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4961     // send host num completed packets next as they don't require num_cmd_packets > 0
4962     if (!hci_can_send_comand_packet_transport()) return;
4963     if (hci_stack->host_completed_packets){
4964         hci_host_num_completed_packets();
4965         return;
4966     }
4967 #endif
4968 
4969     if (!hci_can_send_command_packet_now()) return;
4970 
4971     // global/non-connection oriented commands
4972 
4973 
4974 #ifdef ENABLE_CLASSIC
4975     // general gap classic
4976     done = hci_run_general_gap_classic();
4977     if (done) return;
4978 #endif
4979 
4980 #ifdef ENABLE_BLE
4981     // general gap le
4982     done = hci_run_general_gap_le();
4983     if (done) return;
4984 #endif
4985 
4986     // send pending HCI commands
4987     done = hci_run_general_pending_commands();
4988     if (done) return;
4989 
4990     // stack state sub statemachines
4991     hci_connection_t * connection;
4992     switch (hci_stack->state){
4993         case HCI_STATE_INITIALIZING:
4994             hci_initializing_run();
4995             break;
4996 
4997         case HCI_STATE_HALTING:
4998 
4999             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
5000             switch (hci_stack->substate){
5001                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5002                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
5003 
5004 #ifdef ENABLE_BLE
5005 #ifdef ENABLE_LE_CENTRAL
5006                     // free whitelist entries
5007                     {
5008                         btstack_linked_list_iterator_t lit;
5009                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
5010                         while (btstack_linked_list_iterator_has_next(&lit)){
5011                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
5012                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
5013                             btstack_memory_whitelist_entry_free(entry);
5014                         }
5015                     }
5016 #endif
5017 #endif
5018                     // close all open connections
5019                     connection =  (hci_connection_t *) hci_stack->connections;
5020                     if (connection){
5021                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
5022                         if (!hci_can_send_command_packet_now()) return;
5023 
5024                         // check state
5025                         if (connection->state == SENT_DISCONNECT) return;
5026                         connection->state = SENT_DISCONNECT;
5027 
5028                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
5029 
5030                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
5031                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
5032 
5033                         // ... which would be ignored anyway as we shutdown (free) the connection now
5034                         hci_shutdown_connection(connection);
5035 
5036                         // finally, send the disconnect command
5037                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5038                         return;
5039                     }
5040 
5041                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
5042                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
5043                         log_info("HCI_STATE_HALTING: wait 50 ms");
5044                         hci_stack->substate = HCI_HALTING_W4_TIMER;
5045                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
5046                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
5047                         btstack_run_loop_add_timer(&hci_stack->timeout);
5048                         break;
5049                     }
5050 
5051                     /* fall through */
5052 
5053                 case HCI_HALTING_CLOSE:
5054                     log_info("HCI_STATE_HALTING, calling off");
5055 
5056                     // switch mode
5057                     hci_power_control_off();
5058 
5059                     log_info("HCI_STATE_HALTING, emitting state");
5060                     hci_emit_state();
5061                     log_info("HCI_STATE_HALTING, done");
5062                     break;
5063 
5064                 case HCI_HALTING_W4_TIMER:
5065                     // keep waiting
5066 
5067                     break;
5068                 default:
5069                     break;
5070             }
5071 
5072             break;
5073 
5074         case HCI_STATE_FALLING_ASLEEP:
5075             switch(hci_stack->substate) {
5076                 case HCI_FALLING_ASLEEP_DISCONNECT:
5077                     log_info("HCI_STATE_FALLING_ASLEEP");
5078                     // close all open connections
5079                     connection =  (hci_connection_t *) hci_stack->connections;
5080                     if (connection){
5081 
5082                         // send disconnect
5083                         if (!hci_can_send_command_packet_now()) return;
5084 
5085                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
5086                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
5087 
5088                         // send disconnected event right away - causes higher layer connections to get closed, too.
5089                         hci_shutdown_connection(connection);
5090                         return;
5091                     }
5092 
5093                     if (hci_classic_supported()){
5094                         // disable page and inquiry scan
5095                         if (!hci_can_send_command_packet_now()) return;
5096 
5097                         log_info("HCI_STATE_HALTING, disabling inq scans");
5098                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
5099 
5100                         // continue in next sub state
5101                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
5102                         break;
5103                     }
5104 
5105                     /* fall through */
5106 
5107                 case HCI_FALLING_ASLEEP_COMPLETE:
5108                     log_info("HCI_STATE_HALTING, calling sleep");
5109                     // switch mode
5110                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
5111                     hci_emit_state();
5112                     break;
5113 
5114                 default:
5115                     break;
5116             }
5117             break;
5118 
5119         default:
5120             break;
5121     }
5122 }
5123 
5124 uint8_t hci_send_cmd_packet(uint8_t *packet, int size){
5125     // house-keeping
5126 
5127 #ifdef ENABLE_CLASSIC
5128     bd_addr_t addr;
5129     hci_connection_t * conn;
5130 #endif
5131 #ifdef ENABLE_LE_CENTRAL
5132     uint8_t initiator_filter_policy;
5133 #endif
5134 
5135     uint16_t opcode = little_endian_read_16(packet, 0);
5136     switch (opcode) {
5137         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
5138             hci_stack->loopback_mode = packet[3];
5139             break;
5140 
5141 #ifdef ENABLE_CLASSIC
5142         case HCI_OPCODE_HCI_CREATE_CONNECTION:
5143             reverse_bd_addr(&packet[3], addr);
5144             log_info("Create_connection to %s", bd_addr_to_str(addr));
5145 
5146             // CVE-2020-26555: reject outgoing connection to device with same BD ADDR
5147             if (memcmp(hci_stack->local_bd_addr, addr, 6) == 0) {
5148                 hci_emit_connection_complete(addr, 0, ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR);
5149                 return ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
5150             }
5151 
5152             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5153             if (!conn) {
5154                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5155                 if (!conn) {
5156                     // notify client that alloc failed
5157                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5158                     return BTSTACK_MEMORY_ALLOC_FAILED; // packet not sent to controller
5159                 }
5160                 conn->state = SEND_CREATE_CONNECTION;
5161                 conn->role  = HCI_ROLE_MASTER;
5162             }
5163 
5164             conn->con_handle = HCI_CON_HANDLE_INVALID;
5165             conn->role = HCI_ROLE_INVALID;
5166 
5167             log_info("conn state %u", conn->state);
5168             // TODO: L2CAP should not send create connection command, instead a (new) gap function should be used
5169             switch (conn->state) {
5170                 // if connection active exists
5171                 case OPEN:
5172                     // and OPEN, emit connection complete command
5173                     hci_emit_connection_complete(addr, conn->con_handle, ERROR_CODE_SUCCESS);
5174                     // packet not sent to controller
5175                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5176                 case RECEIVED_DISCONNECTION_COMPLETE:
5177                     // create connection triggered in disconnect complete event, let's do it now
5178                     break;
5179                 case SEND_CREATE_CONNECTION:
5180                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
5181                     break;
5182                 default:
5183                     // otherwise, just ignore as it is already in the open process
5184                     // packet not sent to controller
5185                     return ERROR_CODE_ACL_CONNECTION_ALREADY_EXISTS;
5186             }
5187             conn->state = SENT_CREATE_CONNECTION;
5188 
5189             // track outgoing connection
5190             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
5191             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
5192             break;
5193         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
5194             if (hci_stack->link_key_db) {
5195                 reverse_bd_addr(&packet[3], addr);
5196                 hci_stack->link_key_db->delete_link_key(addr);
5197             }
5198             break;
5199 
5200 #if defined (ENABLE_SCO_OVER_HCI) || defined (HAVE_SCO_TRANSPORT)
5201         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
5202             // setup_synchronous_connection? Voice setting at offset 22
5203             // TODO: compare to current setting if sco connection already active
5204             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
5205             break;
5206         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
5207             // accept_synchronus_connection? Voice setting at offset 18
5208             // TODO: compare to current setting if sco connection already active
5209             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
5210             break;
5211 #endif
5212 #endif
5213 
5214 #ifdef ENABLE_BLE
5215         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
5216             hci_stack->le_random_address_set = 1;
5217             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
5218             break;
5219 #ifdef ENABLE_LE_PERIPHERAL
5220         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
5221             hci_stack->le_advertisements_active = packet[3] != 0;
5222             break;
5223 #endif
5224 #ifdef ENABLE_LE_CENTRAL
5225         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
5226             // white list used?
5227             initiator_filter_policy = packet[7];
5228             switch (initiator_filter_policy) {
5229                 case 0:
5230                     // whitelist not used
5231                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
5232                     break;
5233                 case 1:
5234                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
5235                     break;
5236                 default:
5237                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
5238                     break;
5239             }
5240             // track outgoing connection
5241             hci_stack->outgoing_addr_type = (bd_addr_type_t) packet[8]; // peer addres type
5242             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
5243             break;
5244         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
5245             hci_stack->le_connecting_state = LE_CONNECTING_CANCEL;
5246             break;
5247 #endif
5248 #endif
5249         default:
5250             break;
5251     }
5252 
5253     hci_stack->num_cmd_packets--;
5254 
5255     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
5256     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
5257     if (err != 0){
5258         return ERROR_CODE_HARDWARE_FAILURE;
5259     }
5260     return ERROR_CODE_SUCCESS;
5261 }
5262 
5263 // disconnect because of security block
5264 void hci_disconnect_security_block(hci_con_handle_t con_handle){
5265     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5266     if (!connection) return;
5267     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
5268 }
5269 
5270 
5271 // Configure Secure Simple Pairing
5272 
5273 #ifdef ENABLE_CLASSIC
5274 
5275 // enable will enable SSP during init
5276 void gap_ssp_set_enable(int enable){
5277     hci_stack->ssp_enable = enable;
5278 }
5279 
5280 static int hci_local_ssp_activated(void){
5281     return gap_ssp_supported() && hci_stack->ssp_enable;
5282 }
5283 
5284 // if set, BTstack will respond to io capability request using authentication requirement
5285 void gap_ssp_set_io_capability(int io_capability){
5286     hci_stack->ssp_io_capability = io_capability;
5287 }
5288 void gap_ssp_set_authentication_requirement(int authentication_requirement){
5289     hci_stack->ssp_authentication_requirement = authentication_requirement;
5290 }
5291 
5292 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
5293 void gap_ssp_set_auto_accept(int auto_accept){
5294     hci_stack->ssp_auto_accept = auto_accept;
5295 }
5296 
5297 void gap_secure_connections_enable(bool enable){
5298     hci_stack->secure_connections_enable = enable;
5299 }
5300 
5301 #endif
5302 
5303 // va_list part of hci_send_cmd
5304 uint8_t hci_send_cmd_va_arg(const hci_cmd_t * cmd, va_list argptr){
5305     if (!hci_can_send_command_packet_now()){
5306         log_error("hci_send_cmd called but cannot send packet now");
5307         return ERROR_CODE_COMMAND_DISALLOWED;
5308     }
5309 
5310     // for HCI INITIALIZATION
5311     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
5312     hci_stack->last_cmd_opcode = cmd->opcode;
5313 
5314     hci_reserve_packet_buffer();
5315     uint8_t * packet = hci_stack->hci_packet_buffer;
5316     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
5317     uint8_t status = hci_send_cmd_packet(packet, size);
5318 
5319     // release packet buffer on error or for synchronous transport implementations
5320     if ((status != ERROR_CODE_SUCCESS) || hci_transport_synchronous()){
5321         hci_release_packet_buffer();
5322         hci_emit_transport_packet_sent();
5323     }
5324 
5325     return status;
5326 }
5327 
5328 /**
5329  * pre: numcmds >= 0 - it's allowed to send a command to the controller
5330  */
5331 uint8_t hci_send_cmd(const hci_cmd_t * cmd, ...){
5332     va_list argptr;
5333     va_start(argptr, cmd);
5334     uint8_t status = hci_send_cmd_va_arg(cmd, argptr);
5335     va_end(argptr);
5336     return status;
5337 }
5338 
5339 // Create various non-HCI events.
5340 // TODO: generalize, use table similar to hci_create_command
5341 
5342 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
5343     // dump packet
5344     if (dump) {
5345         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
5346     }
5347 
5348     // dispatch to all event handlers
5349     btstack_linked_list_iterator_t it;
5350     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
5351     while (btstack_linked_list_iterator_has_next(&it)){
5352         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
5353         entry->callback(HCI_EVENT_PACKET, 0, event, size);
5354     }
5355 }
5356 
5357 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
5358     if (!hci_stack->acl_packet_handler) return;
5359     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
5360 }
5361 
5362 #ifdef ENABLE_CLASSIC
5363 static void hci_notify_if_sco_can_send_now(void){
5364     // notify SCO sender if waiting
5365     if (!hci_stack->sco_waiting_for_can_send_now) return;
5366     if (hci_can_send_sco_packet_now()){
5367         hci_stack->sco_waiting_for_can_send_now = 0;
5368         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
5369         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
5370         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
5371     }
5372 }
5373 
5374 // parsing end emitting has been merged to reduce code size
5375 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
5376     uint8_t event[28+GAP_INQUIRY_MAX_NAME_LEN];
5377 
5378     uint8_t * eir_data;
5379     ad_context_t context;
5380     const uint8_t * name;
5381     uint8_t         name_len;
5382 
5383     if (size < 3) return;
5384 
5385     int event_type = hci_event_packet_get_type(packet);
5386     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
5387     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
5388 
5389     switch (event_type){
5390         case HCI_EVENT_INQUIRY_RESULT:
5391         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5392             if (size != (3 + (num_responses * 14))) return;
5393             break;
5394         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5395             if (size != 257) return;
5396             if (num_responses != 1) return;
5397             break;
5398         default:
5399             return;
5400     }
5401 
5402     // event[1] is set at the end
5403     int i;
5404     for (i=0; i<num_responses;i++){
5405         memset(event, 0, sizeof(event));
5406         event[0] = GAP_EVENT_INQUIRY_RESULT;
5407         uint8_t event_size = 27;    // if name is not set by EIR
5408 
5409         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
5410         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
5411         (void)memcpy(&event[9],
5412                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
5413                      3); // class of device
5414         (void)memcpy(&event[12],
5415                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
5416                      2); // clock offset
5417 
5418         switch (event_type){
5419             case HCI_EVENT_INQUIRY_RESULT:
5420                 // 14,15,16,17 = 0, size 18
5421                 break;
5422             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
5423                 event[14] = 1;
5424                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5425                 // 16,17 = 0, size 18
5426                 break;
5427             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
5428                 event[14] = 1;
5429                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
5430                 // EIR packets only contain a single inquiry response
5431                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
5432                 name = NULL;
5433                 // Iterate over EIR data
5434                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
5435                     uint8_t data_type    = ad_iterator_get_data_type(&context);
5436                     uint8_t data_size    = ad_iterator_get_data_len(&context);
5437                     const uint8_t * data = ad_iterator_get_data(&context);
5438                     // Prefer Complete Local Name over Shortened Local Name
5439                     switch (data_type){
5440                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
5441                             if (name) continue;
5442                             /* fall through */
5443                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
5444                             name = data;
5445                             name_len = data_size;
5446                             break;
5447                         case BLUETOOTH_DATA_TYPE_DEVICE_ID:
5448                             if (data_size != 8) break;
5449                             event[16] = 1;
5450                             memcpy(&event[17], data, 8);
5451                             break;
5452                         default:
5453                             break;
5454                     }
5455                 }
5456                 if (name){
5457                     event[25] = 1;
5458                     // truncate name if needed
5459                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
5460                     event[26] = len;
5461                     (void)memcpy(&event[27], name, len);
5462                     event_size += len;
5463                 }
5464                 break;
5465             default:
5466                 return;
5467         }
5468         event[1] = event_size - 2;
5469         hci_emit_event(event, event_size, 1);
5470     }
5471 }
5472 #endif
5473 
5474 void hci_emit_state(void){
5475     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
5476     uint8_t event[3];
5477     event[0] = BTSTACK_EVENT_STATE;
5478     event[1] = sizeof(event) - 2u;
5479     event[2] = hci_stack->state;
5480     hci_emit_event(event, sizeof(event), 1);
5481 }
5482 
5483 #ifdef ENABLE_CLASSIC
5484 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
5485     uint8_t event[13];
5486     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
5487     event[1] = sizeof(event) - 2;
5488     event[2] = status;
5489     little_endian_store_16(event, 3, con_handle);
5490     reverse_bd_addr(address, &event[5]);
5491     event[11] = 1; // ACL connection
5492     event[12] = 0; // encryption disabled
5493     hci_emit_event(event, sizeof(event), 1);
5494 }
5495 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
5496     if (disable_l2cap_timeouts) return;
5497     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
5498     uint8_t event[4];
5499     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
5500     event[1] = sizeof(event) - 2;
5501     little_endian_store_16(event, 2, conn->con_handle);
5502     hci_emit_event(event, sizeof(event), 1);
5503 }
5504 #endif
5505 
5506 #ifdef ENABLE_BLE
5507 #ifdef ENABLE_LE_CENTRAL
5508 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){
5509     uint8_t event[21];
5510     event[0] = HCI_EVENT_LE_META;
5511     event[1] = sizeof(event) - 2u;
5512     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
5513     event[3] = status;
5514     little_endian_store_16(event, 4, con_handle);
5515     event[6] = 0; // TODO: role
5516     event[7] = address_type;
5517     reverse_bd_addr(address, &event[8]);
5518     little_endian_store_16(event, 14, 0); // interval
5519     little_endian_store_16(event, 16, 0); // latency
5520     little_endian_store_16(event, 18, 0); // supervision timeout
5521     event[20] = 0; // master clock accuracy
5522     hci_emit_event(event, sizeof(event), 1);
5523 }
5524 #endif
5525 #endif
5526 
5527 static void hci_emit_transport_packet_sent(void){
5528     // notify upper stack that it might be possible to send again
5529     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
5530     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
5531 }
5532 
5533 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
5534     uint8_t event[6];
5535     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
5536     event[1] = sizeof(event) - 2u;
5537     event[2] = 0; // status = OK
5538     little_endian_store_16(event, 3, con_handle);
5539     event[5] = reason;
5540     hci_emit_event(event, sizeof(event), 1);
5541 }
5542 
5543 static void hci_emit_nr_connections_changed(void){
5544     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
5545     uint8_t event[3];
5546     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
5547     event[1] = sizeof(event) - 2u;
5548     event[2] = nr_hci_connections();
5549     hci_emit_event(event, sizeof(event), 1);
5550 }
5551 
5552 static void hci_emit_hci_open_failed(void){
5553     log_info("BTSTACK_EVENT_POWERON_FAILED");
5554     uint8_t event[2];
5555     event[0] = BTSTACK_EVENT_POWERON_FAILED;
5556     event[1] = sizeof(event) - 2u;
5557     hci_emit_event(event, sizeof(event), 1);
5558 }
5559 
5560 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
5561     log_info("hci_emit_dedicated_bonding_result %u ", status);
5562     uint8_t event[9];
5563     int pos = 0;
5564     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
5565     event[pos++] = sizeof(event) - 2u;
5566     event[pos++] = status;
5567     reverse_bd_addr(address, &event[pos]);
5568     hci_emit_event(event, sizeof(event), 1);
5569 }
5570 
5571 
5572 #ifdef ENABLE_CLASSIC
5573 
5574 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
5575     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
5576     uint8_t event[5];
5577     int pos = 0;
5578     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
5579     event[pos++] = sizeof(event) - 2;
5580     little_endian_store_16(event, 2, con_handle);
5581     pos += 2;
5582     event[pos++] = level;
5583     hci_emit_event(event, sizeof(event), 1);
5584 }
5585 
5586 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
5587     if (!connection) return LEVEL_0;
5588     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
5589     // BIAS: we only consider Authenticated if the connection is already encrypted, which requires that both sides have link key
5590     if ((connection->authentication_flags & AUTH_FLAG_CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
5591     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
5592     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
5593     // LEVEL 4 always requires 128 bit encrytion key size
5594     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
5595         security_level = LEVEL_3;
5596     }
5597     return security_level;
5598 }
5599 
5600 static void hci_emit_discoverable_enabled(uint8_t enabled){
5601     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
5602     uint8_t event[3];
5603     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
5604     event[1] = sizeof(event) - 2;
5605     event[2] = enabled;
5606     hci_emit_event(event, sizeof(event), 1);
5607 }
5608 
5609 // query if remote side supports eSCO
5610 bool hci_remote_esco_supported(hci_con_handle_t con_handle){
5611     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5612     if (!connection) return false;
5613     return (connection->remote_supported_features[0] & 1) != 0;
5614 }
5615 
5616 static bool hci_ssp_supported(hci_connection_t * connection){
5617     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
5618     return (connection->bonding_flags & mask) == mask;
5619 }
5620 
5621 // query if remote side supports SSP
5622 bool hci_remote_ssp_supported(hci_con_handle_t con_handle){
5623     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5624     if (!connection) return false;
5625     return hci_ssp_supported(connection) ? 1 : 0;
5626 }
5627 
5628 bool gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
5629     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
5630 }
5631 
5632 // GAP API
5633 /**
5634  * @bbrief enable/disable bonding. default is enabled
5635  * @praram enabled
5636  */
5637 void gap_set_bondable_mode(int enable){
5638     hci_stack->bondable = enable ? 1 : 0;
5639 }
5640 /**
5641  * @brief Get bondable mode.
5642  * @return 1 if bondable
5643  */
5644 int gap_get_bondable_mode(void){
5645     return hci_stack->bondable;
5646 }
5647 
5648 /**
5649  * @brief map link keys to security levels
5650  */
5651 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
5652     switch (link_key_type){
5653         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5654             return LEVEL_4;
5655         case COMBINATION_KEY:
5656         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5657             return LEVEL_3;
5658         default:
5659             return LEVEL_2;
5660     }
5661 }
5662 
5663 /**
5664  * @brief map link keys to secure connection yes/no
5665  */
5666 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
5667     switch (link_key_type){
5668         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5669         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5670             return 1;
5671         default:
5672             return 0;
5673     }
5674 }
5675 
5676 /**
5677  * @brief map link keys to authenticated
5678  */
5679 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
5680     switch (link_key_type){
5681         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
5682         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
5683             return 1;
5684         default:
5685             return 0;
5686     }
5687 }
5688 
5689 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
5690     log_info("gap_mitm_protection_required_for_security_level %u", level);
5691     return level > LEVEL_2;
5692 }
5693 
5694 /**
5695  * @brief get current security level
5696  */
5697 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
5698     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5699     if (!connection) return LEVEL_0;
5700     return gap_security_level_for_connection(connection);
5701 }
5702 
5703 /**
5704  * @brief request connection to device to
5705  * @result GAP_AUTHENTICATION_RESULT
5706  */
5707 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
5708     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5709     if (!connection){
5710         hci_emit_security_level(con_handle, LEVEL_0);
5711         return;
5712     }
5713 
5714     btstack_assert(hci_is_le_connection(connection) == false);
5715 
5716     // 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)
5717     // available on the BR/EDR physical transport require Security Mode 4, Level 4 "
5718     if (hci_stack->gap_secure_connections_only_mode && (requested_level != LEVEL_0)){
5719         requested_level = LEVEL_4;
5720     }
5721 
5722     gap_security_level_t current_level = gap_security_level(con_handle);
5723     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
5724         requested_level, connection->requested_security_level, current_level);
5725 
5726     // authentication active if authentication request was sent or planned level > 0
5727     bool authentication_active = ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) || (connection->requested_security_level > LEVEL_0);
5728     if (authentication_active){
5729         // authentication already active
5730         if (connection->requested_security_level < requested_level){
5731             // increase requested level as new level is higher
5732             // TODO: handle re-authentication when done
5733             connection->requested_security_level = requested_level;
5734         }
5735     } else {
5736         // no request active, notify if security sufficient
5737         if (requested_level <= current_level){
5738             hci_emit_security_level(con_handle, current_level);
5739             return;
5740         }
5741 
5742         // store request
5743         connection->requested_security_level = requested_level;
5744 
5745         // start to authenticate connection
5746         connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
5747         hci_run();
5748     }
5749 }
5750 
5751 /**
5752  * @brief start dedicated bonding with device. disconnect after bonding
5753  * @param device
5754  * @param request MITM protection
5755  * @result GAP_DEDICATED_BONDING_COMPLETE
5756  */
5757 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
5758 
5759     // create connection state machine
5760     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
5761 
5762     if (!connection){
5763         return BTSTACK_MEMORY_ALLOC_FAILED;
5764     }
5765 
5766     // delete linkn key
5767     gap_drop_link_key_for_bd_addr(device);
5768 
5769     // configure LEVEL_2/3, dedicated bonding
5770     connection->state = SEND_CREATE_CONNECTION;
5771     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
5772     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
5773     connection->bonding_flags = BONDING_DEDICATED;
5774 
5775     // wait for GAP Security Result and send GAP Dedicated Bonding complete
5776 
5777     // handle: connnection failure (connection complete != ok)
5778     // handle: authentication failure
5779     // handle: disconnect on done
5780 
5781     hci_run();
5782 
5783     return 0;
5784 }
5785 
5786 void gap_set_local_name(const char * local_name){
5787     hci_stack->local_name = local_name;
5788     hci_stack->gap_tasks |= GAP_TASK_SET_LOCAL_NAME;
5789     // also update EIR if not set by user
5790     if (hci_stack->eir_data == NULL){
5791         hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
5792     }
5793     hci_run();
5794 }
5795 #endif
5796 
5797 
5798 #ifdef ENABLE_BLE
5799 
5800 #ifdef ENABLE_LE_CENTRAL
5801 void gap_start_scan(void){
5802     hci_stack->le_scanning_enabled = true;
5803     hci_run();
5804 }
5805 
5806 void gap_stop_scan(void){
5807     hci_stack->le_scanning_enabled = false;
5808     hci_run();
5809 }
5810 
5811 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
5812     hci_stack->le_scan_type          = scan_type;
5813     hci_stack->le_scan_filter_policy = scanning_filter_policy;
5814     hci_stack->le_scan_interval      = scan_interval;
5815     hci_stack->le_scan_window        = scan_window;
5816     hci_stack->le_scanning_param_update = true;
5817     hci_run();
5818 }
5819 
5820 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
5821     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
5822 }
5823 
5824 uint8_t gap_connect(const bd_addr_t addr, bd_addr_type_t addr_type){
5825     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
5826     if (!conn){
5827         // disallow if le connection is already outgoing
5828         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5829             log_error("le connection already active");
5830             return ERROR_CODE_COMMAND_DISALLOWED;
5831         }
5832 
5833         log_info("gap_connect: no connection exists yet, creating context");
5834         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
5835         if (!conn){
5836             // notify client that alloc failed
5837             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
5838             log_info("gap_connect: failed to alloc hci_connection_t");
5839             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
5840         }
5841 
5842         // set le connecting state
5843         if (hci_is_le_connection_type(addr_type)){
5844             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
5845         }
5846 
5847         conn->state = SEND_CREATE_CONNECTION;
5848         log_info("gap_connect: send create connection next");
5849         hci_run();
5850         return ERROR_CODE_SUCCESS;
5851     }
5852 
5853     if (!hci_is_le_connection(conn) ||
5854         (conn->state == SEND_CREATE_CONNECTION) ||
5855         (conn->state == SENT_CREATE_CONNECTION)) {
5856         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
5857         log_error("gap_connect: classic connection or connect is already being created");
5858         return GATT_CLIENT_IN_WRONG_STATE;
5859     }
5860 
5861     // check if connection was just disconnected
5862     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5863         log_info("gap_connect: send create connection (again)");
5864         conn->state = SEND_CREATE_CONNECTION;
5865         hci_run();
5866         return ERROR_CODE_SUCCESS;
5867     }
5868 
5869     log_info("gap_connect: context exists with state %u", conn->state);
5870     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
5871     hci_run();
5872     return ERROR_CODE_SUCCESS;
5873 }
5874 
5875 // @assumption: only a single outgoing LE Connection exists
5876 static hci_connection_t * gap_get_outgoing_connection(void){
5877     btstack_linked_item_t *it;
5878     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5879         hci_connection_t * conn = (hci_connection_t *) it;
5880         if (!hci_is_le_connection(conn)) continue;
5881         switch (conn->state){
5882             case SEND_CREATE_CONNECTION:
5883             case SENT_CREATE_CONNECTION:
5884             case SENT_CANCEL_CONNECTION:
5885                 return conn;
5886             default:
5887                 break;
5888         };
5889     }
5890     return NULL;
5891 }
5892 
5893 uint8_t gap_connect_cancel(void){
5894     hci_connection_t * conn = gap_get_outgoing_connection();
5895     if (!conn) return 0;
5896     switch (conn->state){
5897         case SEND_CREATE_CONNECTION:
5898             // skip sending create connection and emit event instead
5899             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5900             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5901             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5902             btstack_memory_hci_connection_free( conn );
5903             break;
5904         case SENT_CREATE_CONNECTION:
5905             // request to send cancel connection
5906             conn->state = SEND_CANCEL_CONNECTION;
5907             hci_run();
5908             break;
5909         default:
5910             break;
5911     }
5912     return 0;
5913 }
5914 #endif
5915 
5916 #ifdef ENABLE_LE_CENTRAL
5917 /**
5918  * @brief Set connection parameters for outgoing connections
5919  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5920  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5921  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5922  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5923  * @param conn_latency, default: 4
5924  * @param supervision_timeout (unit: 10ms), default: 720 ms
5925  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5926  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5927  */
5928 
5929 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5930     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5931     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5932     hci_stack->le_connection_scan_interval = conn_scan_interval;
5933     hci_stack->le_connection_scan_window = conn_scan_window;
5934     hci_stack->le_connection_interval_min = conn_interval_min;
5935     hci_stack->le_connection_interval_max = conn_interval_max;
5936     hci_stack->le_connection_latency = conn_latency;
5937     hci_stack->le_supervision_timeout = supervision_timeout;
5938     hci_stack->le_minimum_ce_length = min_ce_length;
5939     hci_stack->le_maximum_ce_length = max_ce_length;
5940 }
5941 #endif
5942 
5943 /**
5944  * @brief Updates the connection parameters for a given LE connection
5945  * @param handle
5946  * @param conn_interval_min (unit: 1.25ms)
5947  * @param conn_interval_max (unit: 1.25ms)
5948  * @param conn_latency
5949  * @param supervision_timeout (unit: 10ms)
5950  * @returns 0 if ok
5951  */
5952 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5953     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5954     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5955     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5956     connection->le_conn_interval_min = conn_interval_min;
5957     connection->le_conn_interval_max = conn_interval_max;
5958     connection->le_conn_latency = conn_latency;
5959     connection->le_supervision_timeout = supervision_timeout;
5960     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5961     hci_run();
5962     return 0;
5963 }
5964 
5965 /**
5966  * @brief Request an update of the connection parameter for a given LE connection
5967  * @param handle
5968  * @param conn_interval_min (unit: 1.25ms)
5969  * @param conn_interval_max (unit: 1.25ms)
5970  * @param conn_latency
5971  * @param supervision_timeout (unit: 10ms)
5972  * @returns 0 if ok
5973  */
5974 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5975     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5976     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5977     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5978     connection->le_conn_interval_min = conn_interval_min;
5979     connection->le_conn_interval_max = conn_interval_max;
5980     connection->le_conn_latency = conn_latency;
5981     connection->le_supervision_timeout = supervision_timeout;
5982     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5983     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5984     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5985     return 0;
5986 }
5987 
5988 #ifdef ENABLE_LE_PERIPHERAL
5989 
5990 /**
5991  * @brief Set Advertisement Data
5992  * @param advertising_data_length
5993  * @param advertising_data (max 31 octets)
5994  * @note data is not copied, pointer has to stay valid
5995  */
5996 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5997     hci_stack->le_advertisements_data_len = advertising_data_length;
5998     hci_stack->le_advertisements_data = advertising_data;
5999     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
6000     hci_run();
6001 }
6002 
6003 /**
6004  * @brief Set Scan Response Data
6005  * @param advertising_data_length
6006  * @param advertising_data (max 31 octets)
6007  * @note data is not copied, pointer has to stay valid
6008  */
6009 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
6010     hci_stack->le_scan_response_data_len = scan_response_data_length;
6011     hci_stack->le_scan_response_data = scan_response_data;
6012     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
6013     hci_run();
6014 }
6015 
6016 /**
6017  * @brief Set Advertisement Parameters
6018  * @param adv_int_min
6019  * @param adv_int_max
6020  * @param adv_type
6021  * @param direct_address_type
6022  * @param direct_address
6023  * @param channel_map
6024  * @param filter_policy
6025  *
6026  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
6027  */
6028  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
6029     uint8_t direct_address_typ, bd_addr_t direct_address,
6030     uint8_t channel_map, uint8_t filter_policy) {
6031 
6032     hci_stack->le_advertisements_interval_min = adv_int_min;
6033     hci_stack->le_advertisements_interval_max = adv_int_max;
6034     hci_stack->le_advertisements_type = adv_type;
6035     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
6036     hci_stack->le_advertisements_channel_map = channel_map;
6037     hci_stack->le_advertisements_filter_policy = filter_policy;
6038     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
6039                  6);
6040 
6041     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS | LE_ADVERTISEMENT_TASKS_PARAMS_SET;
6042     hci_run();
6043  }
6044 
6045 /**
6046  * @brief Enable/Disable Advertisements
6047  * @param enabled
6048  */
6049 void gap_advertisements_enable(int enabled){
6050     hci_stack->le_advertisements_enabled = enabled != 0;
6051     hci_update_advertisements_enabled_for_current_roles();
6052     hci_run();
6053 }
6054 
6055 #endif
6056 
6057 void hci_le_set_own_address_type(uint8_t own_address_type){
6058     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
6059     if (own_address_type == hci_stack->le_own_addr_type) return;
6060     hci_stack->le_own_addr_type = own_address_type;
6061 
6062 #ifdef ENABLE_LE_PERIPHERAL
6063     // update advertisement parameters, too
6064     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
6065     hci_run();
6066 #endif
6067 #ifdef ENABLE_LE_CENTRAL
6068     // note: we don't update scan parameters or modify ongoing connection attempts
6069 #endif
6070 }
6071 
6072 #endif
6073 
6074 uint8_t gap_disconnect(hci_con_handle_t handle){
6075     hci_connection_t * conn = hci_connection_for_handle(handle);
6076     if (!conn){
6077         hci_emit_disconnection_complete(handle, 0);
6078         return 0;
6079     }
6080     // ignore if already disconnected
6081     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
6082         return 0;
6083     }
6084     conn->state = SEND_DISCONNECT;
6085     hci_run();
6086     return 0;
6087 }
6088 
6089 int gap_read_rssi(hci_con_handle_t con_handle){
6090     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6091     if (hci_connection == NULL) return 0;
6092     connectionSetAuthenticationFlags(hci_connection, AUTH_FLAG_READ_RSSI);
6093     hci_run();
6094     return 1;
6095 }
6096 
6097 /**
6098  * @brief Get connection type
6099  * @param con_handle
6100  * @result connection_type
6101  */
6102 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
6103     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6104     if (!conn) return GAP_CONNECTION_INVALID;
6105     switch (conn->address_type){
6106         case BD_ADDR_TYPE_LE_PUBLIC:
6107         case BD_ADDR_TYPE_LE_RANDOM:
6108             return GAP_CONNECTION_LE;
6109         case BD_ADDR_TYPE_SCO:
6110             return GAP_CONNECTION_SCO;
6111         case BD_ADDR_TYPE_ACL:
6112             return GAP_CONNECTION_ACL;
6113         default:
6114             return GAP_CONNECTION_INVALID;
6115     }
6116 }
6117 
6118 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
6119     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
6120     if (!conn) return HCI_ROLE_INVALID;
6121     return (hci_role_t) conn->role;
6122 }
6123 
6124 
6125 #ifdef ENABLE_CLASSIC
6126 uint8_t gap_request_role(const bd_addr_t addr, hci_role_t role){
6127     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6128     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6129     conn->request_role = role;
6130     hci_run();
6131     return ERROR_CODE_SUCCESS;
6132 }
6133 #endif
6134 
6135 #ifdef ENABLE_BLE
6136 
6137 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){
6138     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6139     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6140 
6141     conn->le_phy_update_all_phys    = all_phys;
6142     conn->le_phy_update_tx_phys     = tx_phys;
6143     conn->le_phy_update_rx_phys     = rx_phys;
6144     conn->le_phy_update_phy_options = phy_options;
6145 
6146     hci_run();
6147 
6148     return 0;
6149 }
6150 
6151 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6152     // check if already in list
6153     btstack_linked_list_iterator_t it;
6154     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6155     while (btstack_linked_list_iterator_has_next(&it)) {
6156         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
6157         if (entry->address_type != address_type) {
6158             continue;
6159         }
6160         if (memcmp(entry->address, address, 6) != 0) {
6161             continue;
6162         }
6163 		// disallow if already scheduled to add
6164 		if ((entry->state & LE_WHITELIST_ADD_TO_CONTROLLER) != 0){
6165 			return ERROR_CODE_COMMAND_DISALLOWED;
6166 		}
6167 		// still on controller, but scheduled to remove -> re-add
6168 		entry->state |= LE_WHITELIST_ADD_TO_CONTROLLER;
6169 		return ERROR_CODE_SUCCESS;
6170     }
6171     // alloc and add to list
6172     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
6173     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
6174     entry->address_type = address_type;
6175     (void)memcpy(entry->address, address, 6);
6176     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
6177     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
6178     return ERROR_CODE_SUCCESS;
6179 }
6180 
6181 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6182     btstack_linked_list_iterator_t it;
6183     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6184     while (btstack_linked_list_iterator_has_next(&it)){
6185         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6186         if (entry->address_type != address_type) {
6187             continue;
6188         }
6189         if (memcmp(entry->address, address, 6) != 0) {
6190             continue;
6191         }
6192         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6193             // remove from controller if already present
6194             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6195         }  else {
6196             // directly remove entry from whitelist
6197             btstack_linked_list_iterator_remove(&it);
6198             btstack_memory_whitelist_entry_free(entry);
6199         }
6200         return ERROR_CODE_SUCCESS;
6201     }
6202     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6203 }
6204 
6205 static void hci_whitelist_clear(void){
6206     btstack_linked_list_iterator_t it;
6207     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
6208     while (btstack_linked_list_iterator_has_next(&it)){
6209         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
6210         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
6211             // remove from controller if already present
6212             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
6213             continue;
6214         }
6215         // directly remove entry from whitelist
6216         btstack_linked_list_iterator_remove(&it);
6217         btstack_memory_whitelist_entry_free(entry);
6218     }
6219 }
6220 
6221 /**
6222  * @brief Clear Whitelist
6223  * @returns 0 if ok
6224  */
6225 uint8_t gap_whitelist_clear(void){
6226     hci_whitelist_clear();
6227     hci_run();
6228     return ERROR_CODE_SUCCESS;
6229 }
6230 
6231 /**
6232  * @brief Add Device to Whitelist
6233  * @param address_typ
6234  * @param address
6235  * @returns 0 if ok
6236  */
6237 uint8_t gap_whitelist_add(bd_addr_type_t address_type, const bd_addr_t address){
6238     uint8_t status = hci_whitelist_add(address_type, address);
6239     if (status){
6240         return status;
6241     }
6242     hci_run();
6243     return ERROR_CODE_SUCCESS;
6244 }
6245 
6246 /**
6247  * @brief Remove Device from Whitelist
6248  * @param address_typ
6249  * @param address
6250  * @returns 0 if ok
6251  */
6252 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, const bd_addr_t address){
6253     uint8_t status = hci_whitelist_remove(address_type, address);
6254     if (status){
6255         return status;
6256     }
6257     hci_run();
6258     return ERROR_CODE_SUCCESS;
6259 }
6260 
6261 #ifdef ENABLE_LE_CENTRAL
6262 /**
6263  *  @brief Connect with Whitelist
6264  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
6265  *  @returns - if ok
6266  */
6267 uint8_t gap_connect_with_whitelist(void){
6268     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
6269         return ERROR_CODE_COMMAND_DISALLOWED;
6270     }
6271     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6272     hci_run();
6273     return ERROR_CODE_SUCCESS;
6274 }
6275 
6276 /**
6277  * @brief Auto Connection Establishment - Start Connecting to device
6278  * @param address_typ
6279  * @param address
6280  * @returns 0 if ok
6281  */
6282 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, const bd_addr_t address){
6283     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6284         return ERROR_CODE_COMMAND_DISALLOWED;
6285     }
6286 
6287     uint8_t status = hci_whitelist_add(address_type, address);
6288     if (status == BTSTACK_MEMORY_ALLOC_FAILED) {
6289         return status;
6290     }
6291 
6292     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
6293 
6294     hci_run();
6295     return ERROR_CODE_SUCCESS;
6296 }
6297 
6298 /**
6299  * @brief Auto Connection Establishment - Stop Connecting to device
6300  * @param address_typ
6301  * @param address
6302  * @returns 0 if ok
6303  */
6304 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, const bd_addr_t address){
6305     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
6306         return ERROR_CODE_COMMAND_DISALLOWED;
6307     }
6308 
6309     hci_whitelist_remove(address_type, address);
6310     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
6311         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6312     }
6313     hci_run();
6314     return 0;
6315 }
6316 
6317 /**
6318  * @brief Auto Connection Establishment - Stop everything
6319  * @note  Convenience function to stop all active auto connection attempts
6320  */
6321 uint8_t gap_auto_connection_stop_all(void){
6322     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
6323         return ERROR_CODE_COMMAND_DISALLOWED;
6324     }
6325     hci_whitelist_clear();
6326     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
6327     hci_run();
6328     return ERROR_CODE_SUCCESS;
6329 }
6330 
6331 uint16_t gap_le_connection_interval(hci_con_handle_t con_handle){
6332     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6333     if (!conn) return 0;
6334     return conn->le_connection_interval;
6335 }
6336 #endif
6337 #endif
6338 
6339 #ifdef ENABLE_CLASSIC
6340 /**
6341  * @brief Set Extended Inquiry Response data
6342  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
6343  * @note has to be done before stack starts up
6344  */
6345 void gap_set_extended_inquiry_response(const uint8_t * data){
6346     hci_stack->eir_data = data;
6347     hci_stack->gap_tasks |= GAP_TASK_SET_EIR_DATA;
6348     hci_run();
6349 }
6350 
6351 /**
6352  * @brief Start GAP Classic Inquiry
6353  * @param duration in 1.28s units
6354  * @return 0 if ok
6355  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
6356  */
6357 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
6358     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
6359     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6360     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
6361         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
6362     }
6363     hci_stack->inquiry_state = duration_in_1280ms_units;
6364     hci_run();
6365     return 0;
6366 }
6367 
6368 /**
6369  * @brief Stop GAP Classic Inquiry
6370  * @returns 0 if ok
6371  */
6372 int gap_inquiry_stop(void){
6373     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
6374         // emit inquiry complete event, before it even started
6375         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
6376         hci_emit_event(event, sizeof(event), 1);
6377         return 0;
6378     }
6379     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
6380     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
6381     hci_run();
6382     return 0;
6383 }
6384 
6385 void gap_inquiry_set_lap(uint32_t lap){
6386     hci_stack->inquiry_lap = lap;
6387 }
6388 
6389 
6390 /**
6391  * @brief Remote Name Request
6392  * @param addr
6393  * @param page_scan_repetition_mode
6394  * @param clock_offset only used when bit 15 is set
6395  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
6396  */
6397 int gap_remote_name_request(const bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
6398     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6399     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
6400     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
6401     hci_stack->remote_name_clock_offset = clock_offset;
6402     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
6403     hci_run();
6404     return 0;
6405 }
6406 
6407 static int gap_pairing_set_state_and_run(const bd_addr_t addr, uint8_t state){
6408     hci_stack->gap_pairing_state = state;
6409     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
6410     hci_run();
6411     return 0;
6412 }
6413 
6414 /**
6415  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
6416  * @param addr
6417  * @param pin_data
6418  * @param pin_len
6419  * @return 0 if ok
6420  */
6421 int gap_pin_code_response_binary(const bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
6422     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6423     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
6424     hci_stack->gap_pairing_pin_len = pin_len;
6425     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
6426 }
6427 
6428 /**
6429  * @brief Legacy Pairing Pin Code Response
6430  * @param addr
6431  * @param pin
6432  * @return 0 if ok
6433  */
6434 int gap_pin_code_response(const bd_addr_t addr, const char * pin){
6435     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
6436 }
6437 
6438 /**
6439  * @brief Abort Legacy Pairing
6440  * @param addr
6441  * @param pin
6442  * @return 0 if ok
6443  */
6444 int gap_pin_code_negative(bd_addr_t addr){
6445     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6446     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
6447 }
6448 
6449 /**
6450  * @brief SSP Passkey Response
6451  * @param addr
6452  * @param passkey
6453  * @return 0 if ok
6454  */
6455 int gap_ssp_passkey_response(const bd_addr_t addr, uint32_t passkey){
6456     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6457     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
6458     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
6459 }
6460 
6461 /**
6462  * @brief Abort SSP Passkey Entry/Pairing
6463  * @param addr
6464  * @param pin
6465  * @return 0 if ok
6466  */
6467 int gap_ssp_passkey_negative(const bd_addr_t addr){
6468     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6469     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
6470 }
6471 
6472 /**
6473  * @brief Accept SSP Numeric Comparison
6474  * @param addr
6475  * @param passkey
6476  * @return 0 if ok
6477  */
6478 int gap_ssp_confirmation_response(const bd_addr_t addr){
6479     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6480     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
6481 }
6482 
6483 /**
6484  * @brief Abort SSP Numeric Comparison/Pairing
6485  * @param addr
6486  * @param pin
6487  * @return 0 if ok
6488  */
6489 int gap_ssp_confirmation_negative(const bd_addr_t addr){
6490     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
6491     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
6492 }
6493 
6494 #if defined(ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY) || defined(ENABLE_EXPLICIT_LINK_KEY_REPLY)
6495 static uint8_t gap_set_auth_flag_and_run(const bd_addr_t addr, hci_authentication_flags_t flag){
6496     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6497     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6498     connectionSetAuthenticationFlags(conn, flag);
6499     hci_run();
6500     return ERROR_CODE_SUCCESS;
6501 }
6502 #endif
6503 
6504 #ifdef ENABLE_EXPLICIT_IO_CAPABILITIES_REPLY
6505 uint8_t gap_ssp_io_capabilities_response(const bd_addr_t addr){
6506     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_REPLY);
6507 }
6508 
6509 uint8_t gap_ssp_io_capabilities_negative(const bd_addr_t addr){
6510     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_SEND_IO_CAPABILITIES_NEGATIVE_REPLY);
6511 }
6512 #endif
6513 
6514 #ifdef ENABLE_CLASSIC_PAIRING_OOB
6515 /**
6516  * @brief Report Remote OOB Data
6517  * @param bd_addr
6518  * @param c_192 Simple Pairing Hash C derived from P-192 public key
6519  * @param r_192 Simple Pairing Randomizer derived from P-192 public key
6520  * @param c_256 Simple Pairing Hash C derived from P-256 public key
6521  * @param r_256 Simple Pairing Randomizer derived from P-256 public key
6522  */
6523 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){
6524     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6525     if (connection == NULL) {
6526         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6527     }
6528     connection->classic_oob_c_192 = c_192;
6529     connection->classic_oob_r_192 = r_192;
6530 
6531     // ignore P-256 if not supported by us
6532     if (hci_stack->secure_connections_active){
6533         connection->classic_oob_c_256 = c_256;
6534         connection->classic_oob_r_256 = r_256;
6535     }
6536 
6537     return ERROR_CODE_SUCCESS;
6538 }
6539 /**
6540  * @brief Generate new OOB data
6541  * @note OOB data will be provided in GAP_EVENT_LOCAL_OOB_DATA and be used in future pairing procedures
6542  */
6543 void gap_ssp_generate_oob_data(void){
6544     hci_stack->classic_read_local_oob_data = true;
6545     hci_run();
6546 }
6547 
6548 #endif
6549 
6550 #ifdef ENABLE_EXPLICIT_LINK_KEY_REPLY
6551 uint8_t gap_send_link_key_response(const bd_addr_t addr, link_key_t link_key, link_key_type_t type){
6552     hci_connection_t * connection = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6553     if (connection == NULL) {
6554         return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
6555     }
6556 
6557     memcpy(connection->link_key, link_key, sizeof(link_key_t));
6558     connection->link_key_type = type;
6559 
6560     return gap_set_auth_flag_and_run(addr, AUTH_FLAG_HANDLE_LINK_KEY_REQUEST);
6561 }
6562 
6563 #endif // ENABLE_EXPLICIT_LINK_KEY_REPLY
6564 /**
6565  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
6566  * @param inquiry_mode see bluetooth_defines.h
6567  */
6568 void hci_set_inquiry_mode(inquiry_mode_t inquiry_mode){
6569     hci_stack->inquiry_mode = inquiry_mode;
6570 }
6571 
6572 /**
6573  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
6574  */
6575 void hci_set_sco_voice_setting(uint16_t voice_setting){
6576     hci_stack->sco_voice_setting = voice_setting;
6577 }
6578 
6579 /**
6580  * @brief Get SCO Voice Setting
6581  * @return current voice setting
6582  */
6583 uint16_t hci_get_sco_voice_setting(void){
6584     return hci_stack->sco_voice_setting;
6585 }
6586 
6587 static int hci_have_usb_transport(void){
6588     if (!hci_stack->hci_transport) return 0;
6589     const char * transport_name = hci_stack->hci_transport->name;
6590     if (!transport_name) return 0;
6591     return (transport_name[0] == 'H') && (transport_name[1] == '2');
6592 }
6593 
6594 /** @brief Get SCO packet length for current SCO Voice setting
6595  *  @note  Using SCO packets of the exact length is required for USB transfer
6596  *  @return Length of SCO packets in bytes (not audio frames)
6597  */
6598 uint16_t hci_get_sco_packet_length(void){
6599     uint16_t sco_packet_length = 0;
6600 
6601 #ifdef ENABLE_SCO_OVER_HCI
6602     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6603     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6604 
6605     if (hci_have_usb_transport()){
6606         // see Core Spec for H2 USB Transfer.
6607         // 3 byte SCO header + 24 bytes per connection
6608         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
6609         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
6610     } else {
6611         // 3 byte SCO header + SCO packet size over the air (60 bytes)
6612         sco_packet_length = 3 + 60 * multiplier;
6613         // assert that it still fits inside an SCO buffer
6614         if (sco_packet_length > hci_stack->sco_data_packet_length){
6615             sco_packet_length = 3 + 60;
6616         }
6617     }
6618 #endif
6619 
6620 #ifdef HAVE_SCO_TRANSPORT
6621     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
6622     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
6623     sco_packet_length = 3 + 60 * multiplier;
6624 #endif
6625     return sco_packet_length;
6626 }
6627 
6628 /**
6629 * @brief Sets the master/slave policy
6630 * @param policy (0: attempt to become master, 1: let connecting device decide)
6631 */
6632 void hci_set_master_slave_policy(uint8_t policy){
6633     hci_stack->master_slave_policy = policy;
6634 }
6635 
6636 #endif
6637 
6638 HCI_STATE hci_get_state(void){
6639     return hci_stack->state;
6640 }
6641 
6642 #ifdef ENABLE_CLASSIC
6643 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr, hci_link_type_t link_type)){
6644     hci_stack->gap_classic_accept_callback = accept_callback;
6645 }
6646 #endif
6647 
6648 /**
6649  * @brief Set callback for Bluetooth Hardware Error
6650  */
6651 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
6652     hci_stack->hardware_error_callback = fn;
6653 }
6654 
6655 void hci_disconnect_all(void){
6656     btstack_linked_list_iterator_t it;
6657     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6658     while (btstack_linked_list_iterator_has_next(&it)){
6659         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6660         if (con->state == SENT_DISCONNECT) continue;
6661         con->state = SEND_DISCONNECT;
6662     }
6663     hci_run();
6664 }
6665 
6666 uint16_t hci_get_manufacturer(void){
6667     return hci_stack->manufacturer;
6668 }
6669 
6670 #ifdef ENABLE_BLE
6671 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
6672     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
6673     if (!hci_con) return NULL;
6674     return &hci_con->sm_connection;
6675 }
6676 
6677 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
6678 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
6679 #endif
6680 
6681 int gap_encryption_key_size(hci_con_handle_t con_handle){
6682     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6683     if (hci_connection == NULL) return 0;
6684     if (hci_is_le_connection(hci_connection)){
6685 #ifdef ENABLE_BLE
6686         sm_connection_t * sm_conn = &hci_connection->sm_connection;
6687         if (sm_conn->sm_connection_encrypted) {
6688             return sm_conn->sm_actual_encryption_key_size;
6689         }
6690 #endif
6691     } else {
6692 #ifdef ENABLE_CLASSIC
6693         if ((hci_connection->authentication_flags & AUTH_FLAG_CONNECTION_ENCRYPTED)){
6694             return hci_connection->encryption_key_size;
6695         }
6696 #endif
6697     }
6698     return 0;
6699 }
6700 
6701 int gap_authenticated(hci_con_handle_t con_handle){
6702     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6703     if (hci_connection == NULL) return 0;
6704 
6705     switch (hci_connection->address_type){
6706 #ifdef ENABLE_BLE
6707         case BD_ADDR_TYPE_LE_PUBLIC:
6708         case BD_ADDR_TYPE_LE_RANDOM:
6709             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6710             return hci_connection->sm_connection.sm_connection_authenticated;
6711 #endif
6712 #ifdef ENABLE_CLASSIC
6713         case BD_ADDR_TYPE_SCO:
6714         case BD_ADDR_TYPE_ACL:
6715             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
6716 #endif
6717         default:
6718             return 0;
6719     }
6720 }
6721 
6722 int gap_secure_connection(hci_con_handle_t con_handle){
6723     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6724     if (hci_connection == NULL) return 0;
6725 
6726     switch (hci_connection->address_type){
6727 #ifdef ENABLE_BLE
6728         case BD_ADDR_TYPE_LE_PUBLIC:
6729         case BD_ADDR_TYPE_LE_RANDOM:
6730             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
6731             return hci_connection->sm_connection.sm_connection_sc;
6732 #endif
6733 #ifdef ENABLE_CLASSIC
6734         case BD_ADDR_TYPE_SCO:
6735         case BD_ADDR_TYPE_ACL:
6736             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
6737 #endif
6738         default:
6739             return 0;
6740     }
6741 }
6742 
6743 bool gap_bonded(hci_con_handle_t con_handle){
6744 	hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
6745 	if (hci_connection == NULL) return 0;
6746 
6747 #ifdef ENABLE_CLASSIC
6748 	link_key_t link_key;
6749 	link_key_type_t link_key_type;
6750 #endif
6751 	switch (hci_connection->address_type){
6752 #ifdef ENABLE_BLE
6753 		case BD_ADDR_TYPE_LE_PUBLIC:
6754 		case BD_ADDR_TYPE_LE_RANDOM:
6755 			return hci_connection->sm_connection.sm_le_db_index >= 0;
6756 #endif
6757 #ifdef ENABLE_CLASSIC
6758 		case BD_ADDR_TYPE_SCO:
6759 		case BD_ADDR_TYPE_ACL:
6760 			return hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(hci_connection->address, link_key, &link_key_type);
6761 #endif
6762 		default:
6763 			return false;
6764 	}
6765 }
6766 
6767 #ifdef ENABLE_BLE
6768 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
6769     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
6770     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
6771     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
6772     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
6773     return sm_conn->sm_connection_authorization_state;
6774 }
6775 #endif
6776 
6777 #ifdef ENABLE_CLASSIC
6778 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){
6779     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6780     if (!conn) return GAP_CONNECTION_INVALID;
6781     conn->sniff_min_interval = sniff_min_interval;
6782     conn->sniff_max_interval = sniff_max_interval;
6783     conn->sniff_attempt = sniff_attempt;
6784     conn->sniff_timeout = sniff_timeout;
6785     hci_run();
6786     return 0;
6787 }
6788 
6789 /**
6790  * @brief Exit Sniff mode
6791  * @param con_handle
6792  @ @return 0 if ok
6793  */
6794 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
6795     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6796     if (!conn) return GAP_CONNECTION_INVALID;
6797     conn->sniff_min_interval = 0xffff;
6798     hci_run();
6799     return 0;
6800 }
6801 
6802 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){
6803     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6804     if (!conn) return GAP_CONNECTION_INVALID;
6805     conn->sniff_subrating_max_latency = max_latency;
6806     conn->sniff_subrating_min_remote_timeout = min_remote_timeout;
6807     conn->sniff_subrating_min_local_timeout = min_local_timeout;
6808     hci_run();
6809     return ERROR_CODE_SUCCESS;
6810 }
6811 
6812 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){
6813     hci_connection_t * conn = hci_connection_for_handle(con_handle);
6814     if (!conn) return GAP_CONNECTION_INVALID;
6815     conn->qos_service_type = service_type;
6816     conn->qos_token_rate = token_rate;
6817     conn->qos_peak_bandwidth = peak_bandwidth;
6818     conn->qos_latency = latency;
6819     conn->qos_delay_variation = delay_variation;
6820     hci_run();
6821     return ERROR_CODE_SUCCESS;
6822 }
6823 
6824 void gap_set_page_scan_activity(uint16_t page_scan_interval, uint16_t page_scan_window){
6825     hci_stack->new_page_scan_interval = page_scan_interval;
6826     hci_stack->new_page_scan_window = page_scan_window;
6827     hci_run();
6828 }
6829 
6830 void gap_set_page_scan_type(page_scan_type_t page_scan_type){
6831     hci_stack->new_page_scan_type = (uint8_t) page_scan_type;
6832     hci_run();
6833 }
6834 
6835 #endif
6836 
6837 void hci_halting_defer(void){
6838     if (hci_stack->state != HCI_STATE_HALTING) return;
6839     switch (hci_stack->substate){
6840         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
6841         case HCI_HALTING_CLOSE:
6842             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
6843             break;
6844         default:
6845             break;
6846     }
6847 }
6848 
6849 #ifdef ENABLE_LE_PRIVACY_ADDRESS_RESOLUTION
6850 void hci_load_le_device_db_entry_into_resolving_list(uint16_t le_device_db_index){
6851     if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6852     if (le_device_db_index >= le_device_db_max_count()) return;
6853     uint8_t offset = le_device_db_index >> 3;
6854     uint8_t mask = 1 << (le_device_db_index & 7);
6855     hci_stack->le_resolving_list_add_entries[offset] |= mask;
6856     if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6857     	// note: go back to remove entries, otherwise, a remove + add will skip the add
6858         hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6859     }
6860 }
6861 
6862 void hci_remove_le_device_db_entry_from_resolving_list(uint16_t le_device_db_index){
6863 	if (le_device_db_index >= MAX_NUM_RESOLVING_LIST_ENTRIES) return;
6864 	if (le_device_db_index >= le_device_db_max_count()) return;
6865 	uint8_t offset = le_device_db_index >> 3;
6866 	uint8_t mask = 1 << (le_device_db_index & 7);
6867 	hci_stack->le_resolving_list_remove_entries[offset] |= mask;
6868 	if (hci_stack->le_resolving_list_state == LE_RESOLVING_LIST_DONE){
6869 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_REMOVE_ENTRIES;
6870 	}
6871 }
6872 
6873 uint8_t gap_load_resolving_list_from_le_device_db(void){
6874 	if ((hci_stack->local_supported_commands[1] & (1 << 2)) == 0) {
6875 		return ERROR_CODE_UNSUPPORTED_FEATURE_OR_PARAMETER_VALUE;
6876 	}
6877 	if (hci_stack->le_resolving_list_state != LE_RESOLVING_LIST_SEND_ENABLE_ADDRESS_RESOLUTION){
6878 		// restart le resolving list update
6879 		hci_stack->le_resolving_list_state = LE_RESOLVING_LIST_READ_SIZE;
6880 	}
6881 	return ERROR_CODE_SUCCESS;
6882 }
6883 #endif
6884 
6885 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
6886 void hci_setup_test_connections_fuzz(void){
6887     hci_connection_t * conn;
6888 
6889     // default address: 66:55:44:33:00:01
6890     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
6891 
6892     // setup Controller info
6893     hci_stack->num_cmd_packets = 255;
6894     hci_stack->acl_packets_total_num = 255;
6895 
6896     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
6897     addr[5] = 0x01;
6898     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6899     conn->con_handle = addr[5];
6900     conn->role  = HCI_ROLE_SLAVE;
6901     conn->state = RECEIVED_CONNECTION_REQUEST;
6902     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6903 
6904     // setup incoming Classic SCO connection with con handle 0x0002
6905     addr[5] = 0x02;
6906     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6907     conn->con_handle = addr[5];
6908     conn->role  = HCI_ROLE_SLAVE;
6909     conn->state = RECEIVED_CONNECTION_REQUEST;
6910     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6911 
6912     // setup ready Classic ACL connection with con handle 0x0003
6913     addr[5] = 0x03;
6914     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
6915     conn->con_handle = addr[5];
6916     conn->role  = HCI_ROLE_SLAVE;
6917     conn->state = OPEN;
6918     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6919 
6920     // setup ready Classic SCO connection with con handle 0x0004
6921     addr[5] = 0x04;
6922     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
6923     conn->con_handle = addr[5];
6924     conn->role  = HCI_ROLE_SLAVE;
6925     conn->state = OPEN;
6926     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6927 
6928     // setup ready LE ACL connection with con handle 0x005 and public address
6929     addr[5] = 0x05;
6930     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
6931     conn->con_handle = addr[5];
6932     conn->role  = HCI_ROLE_SLAVE;
6933     conn->state = OPEN;
6934     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
6935     conn->sm_connection.sm_connection_encrypted = 1;
6936 }
6937 
6938 void hci_free_connections_fuzz(void){
6939     btstack_linked_list_iterator_t it;
6940     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
6941     while (btstack_linked_list_iterator_has_next(&it)){
6942         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
6943         btstack_linked_list_iterator_remove(&it);
6944         btstack_memory_hci_connection_free(con);
6945     }
6946 }
6947 void hci_simulate_working_fuzz(void){
6948     hci_init_done();
6949     hci_stack->num_cmd_packets = 255;
6950 }
6951 #endif
6952