xref: /btstack/src/hci.c (revision c163146e41d858bcd94331e0e16e049ba35c1f6c)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <inttypes.h>
67 
68 #include "btstack_debug.h"
69 #include "btstack_event.h"
70 #include "btstack_linked_list.h"
71 #include "btstack_memory.h"
72 #include "bluetooth_company_id.h"
73 #include "bluetooth_data_types.h"
74 #include "gap.h"
75 #include "hci.h"
76 #include "hci_cmd.h"
77 #include "hci_dump.h"
78 #include "ad_parser.h"
79 
80 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
81 #ifndef HCI_HOST_ACL_PACKET_NUM
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
83 #endif
84 #ifndef HCI_HOST_ACL_PACKET_LEN
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_NUM
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
89 #endif
90 #ifndef HCI_HOST_SCO_PACKET_LEN
91 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
92 #endif
93 #endif
94 
95 #define HCI_CONNECTION_TIMEOUT_MS 10000
96 
97 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
98 #define HCI_RESET_RESEND_TIMEOUT_MS 200
99 #endif
100 
101 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
102 #ifndef GAP_INQUIRY_MAX_NAME_LEN
103 #define GAP_INQUIRY_MAX_NAME_LEN 32
104 #endif
105 
106 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
107 #define GAP_INQUIRY_DURATION_MIN 0x01
108 #define GAP_INQUIRY_DURATION_MAX 0x30
109 #define GAP_INQUIRY_STATE_ACTIVE 0x80
110 #define GAP_INQUIRY_STATE_IDLE 0
111 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
112 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
113 
114 // GAP Remote Name Request
115 #define GAP_REMOTE_NAME_STATE_IDLE 0
116 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
117 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
118 
119 // GAP Pairing
120 #define GAP_PAIRING_STATE_IDLE                       0
121 #define GAP_PAIRING_STATE_SEND_PIN                   1
122 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
123 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
124 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
125 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
127 
128 
129 // prototypes
130 #ifdef ENABLE_CLASSIC
131 static void hci_update_scan_enable(void);
132 static void hci_emit_discoverable_enabled(uint8_t enabled);
133 static int  hci_local_ssp_activated(void);
134 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
135 static bool hci_ssp_supported(hci_connection_t * connection);
136 static void hci_notify_if_sco_can_send_now(void);
137 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
138 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
139 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
140 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
141 static void hci_connection_timestamp(hci_connection_t *connection);
142 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
143 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
144 #endif
145 
146 static int  hci_power_control_on(void);
147 static void hci_power_control_off(void);
148 static void hci_state_reset(void);
149 static void hci_emit_transport_packet_sent(void);
150 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
151 static void hci_emit_nr_connections_changed(void);
152 static void hci_emit_hci_open_failed(void);
153 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
154 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
155 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
156 static void hci_run(void);
157 static int  hci_is_le_connection(hci_connection_t * connection);
158 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
159 
160 #ifdef ENABLE_CLASSIC
161 static int hci_have_usb_transport(void);
162 #endif
163 
164 #ifdef ENABLE_BLE
165 #ifdef ENABLE_LE_CENTRAL
166 // called from test/ble_client/advertising_data_parser.c
167 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
168 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address);
169 static hci_connection_t * gap_get_outgoing_connection(void);
170 #endif
171 #endif
172 
173 // the STACK is here
174 #ifndef HAVE_MALLOC
175 static hci_stack_t   hci_stack_static;
176 #endif
177 static hci_stack_t * hci_stack = NULL;
178 
179 #ifdef ENABLE_CLASSIC
180 // default name
181 static const char * default_classic_name = "BTstack 00:00:00:00:00:00";
182 
183 // test helper
184 static uint8_t disable_l2cap_timeouts = 0;
185 #endif
186 
187 /**
188  * create connection for given address
189  *
190  * @return connection OR NULL, if no memory left
191  */
192 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
193     log_info("create_connection_for_addr %s, type %x", bd_addr_to_str(addr), addr_type);
194     hci_connection_t * conn = btstack_memory_hci_connection_get();
195     if (!conn) return NULL;
196     bd_addr_copy(conn->address, addr);
197     conn->role = HCI_ROLE_INVALID;
198     conn->address_type = addr_type;
199     conn->con_handle = 0xffff;
200     conn->authentication_flags = AUTH_FLAGS_NONE;
201     conn->bonding_flags = 0;
202     conn->requested_security_level = LEVEL_0;
203 #ifdef ENABLE_CLASSIC
204     conn->request_role = HCI_ROLE_INVALID;
205     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
206     btstack_run_loop_set_timer_context(&conn->timeout, conn);
207     hci_connection_timestamp(conn);
208 #endif
209     conn->acl_recombination_length = 0;
210     conn->acl_recombination_pos = 0;
211     conn->num_packets_sent = 0;
212 
213     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
214 #ifdef ENABLE_BLE
215     conn->le_phy_update_all_phys = 0xff;
216 #endif
217 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
218     conn->le_max_tx_octets = 27;
219 #endif
220     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
221     return conn;
222 }
223 
224 
225 /**
226  * get le connection parameter range
227 *
228  * @return le connection parameter range struct
229  */
230 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
231     *range = hci_stack->le_connection_parameter_range;
232 }
233 
234 /**
235  * set le connection parameter range
236  *
237  */
238 
239 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
240     hci_stack->le_connection_parameter_range = *range;
241 }
242 
243 /**
244  * @brief Test if connection parameters are inside in existing rage
245  * @param conn_interval_min (unit: 1.25ms)
246  * @param conn_interval_max (unit: 1.25ms)
247  * @param conn_latency
248  * @param supervision_timeout (unit: 10ms)
249  * @returns 1 if included
250  */
251 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){
252     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
253     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
254 
255     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
256     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
257 
258     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
259     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
260 
261     return 1;
262 }
263 
264 /**
265  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
266  * @note: default: 1
267  * @param max_peripheral_connections
268  */
269 #ifdef ENABLE_LE_PERIPHERAL
270 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
271     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
272 }
273 #endif
274 
275 /**
276  * get hci connections iterator
277  *
278  * @return hci connections iterator
279  */
280 
281 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
282     btstack_linked_list_iterator_init(it, &hci_stack->connections);
283 }
284 
285 /**
286  * get connection for a given handle
287  *
288  * @return connection OR NULL, if not found
289  */
290 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
291     btstack_linked_list_iterator_t it;
292     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
293     while (btstack_linked_list_iterator_has_next(&it)){
294         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
295         if ( item->con_handle == con_handle ) {
296             return item;
297         }
298     }
299     return NULL;
300 }
301 
302 /**
303  * get connection for given address
304  *
305  * @return connection OR NULL, if not found
306  */
307 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
308     btstack_linked_list_iterator_t it;
309     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
310     while (btstack_linked_list_iterator_has_next(&it)){
311         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
312         if (connection->address_type != addr_type)  continue;
313         if (memcmp(addr, connection->address, 6) != 0) continue;
314         return connection;
315     }
316     return NULL;
317 }
318 
319 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
320     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
321 }
322 
323 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
324     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
325 }
326 
327 #ifdef ENABLE_CLASSIC
328 
329 #ifdef ENABLE_SCO_OVER_HCI
330 static int hci_number_sco_connections(void){
331     int connections = 0;
332     btstack_linked_list_iterator_t it;
333     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
334     while (btstack_linked_list_iterator_has_next(&it)){
335         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
336         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
337         connections++;
338     }
339     return connections;
340 }
341 #endif
342 
343 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
344     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
345 #ifdef HAVE_EMBEDDED_TICK
346     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
347         // connections might be timed out
348         hci_emit_l2cap_check_timeout(connection);
349     }
350 #else
351     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
352         // connections might be timed out
353         hci_emit_l2cap_check_timeout(connection);
354     }
355 #endif
356 }
357 
358 static void hci_connection_timestamp(hci_connection_t *connection){
359 #ifdef HAVE_EMBEDDED_TICK
360     connection->timestamp = btstack_run_loop_embedded_get_ticks();
361 #else
362     connection->timestamp = btstack_run_loop_get_time_ms();
363 #endif
364 }
365 
366 /**
367  * add authentication flags and reset timer
368  * @note: assumes classic connection
369  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
370  */
371 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
372     bd_addr_t addr;
373     reverse_bd_addr(bd_addr, addr);
374     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
375     if (conn) {
376         connectionSetAuthenticationFlags(conn, flags);
377         hci_connection_timestamp(conn);
378     }
379 }
380 
381 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
382     hci_connection_t * conn = hci_connection_for_handle(handle);
383     if (!conn) return 0;
384     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
385     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
386     return 0;
387 }
388 
389 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
390     if (!hci_stack->link_key_db) return;
391     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
392     hci_stack->link_key_db->delete_link_key(addr);
393 }
394 
395 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
396     if (!hci_stack->link_key_db) return;
397     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
398     hci_stack->link_key_db->put_link_key(addr, link_key, type);
399 }
400 
401 void gap_delete_all_link_keys(void){
402     bd_addr_t  addr;
403     link_key_t link_key;
404     link_key_type_t type;
405     btstack_link_key_iterator_t it;
406     int ok = gap_link_key_iterator_init(&it);
407     if (!ok) {
408         log_error("could not initialize iterator");
409         return;
410     }
411     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
412         gap_drop_link_key_for_bd_addr(addr);
413     }
414     gap_link_key_iterator_done(&it);
415 }
416 
417 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
418     if (!hci_stack->link_key_db) return 0;
419     if (!hci_stack->link_key_db->iterator_init) return 0;
420     return hci_stack->link_key_db->iterator_init(it);
421 }
422 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){
423     if (!hci_stack->link_key_db) return 0;
424     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
425 }
426 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
427     if (!hci_stack->link_key_db) return;
428     hci_stack->link_key_db->iterator_done(it);
429 }
430 #endif
431 
432 static bool hci_is_le_connection_type(bd_addr_type_t address_type){
433     switch (address_type){
434         case BD_ADDR_TYPE_LE_PUBLIC:
435         case BD_ADDR_TYPE_LE_RANDOM:
436         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
437         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
438             return true;
439         default:
440             return false;
441     }
442 }
443 
444 static int hci_is_le_connection(hci_connection_t * connection){
445     return hci_is_le_connection_type(connection->address_type);
446 }
447 
448 /**
449  * count connections
450  */
451 static int nr_hci_connections(void){
452     int count = 0;
453     btstack_linked_item_t *it;
454     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
455         count++;
456     }
457     return count;
458 }
459 
460 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
461 
462     unsigned int num_packets_sent_classic = 0;
463     unsigned int num_packets_sent_le = 0;
464 
465     btstack_linked_item_t *it;
466     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
467         hci_connection_t * connection = (hci_connection_t *) it;
468         if (hci_is_le_connection(connection)){
469             num_packets_sent_le += connection->num_packets_sent;
470         }
471         if (connection->address_type == BD_ADDR_TYPE_ACL){
472             num_packets_sent_classic += connection->num_packets_sent;
473         }
474     }
475     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
476     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
477     int free_slots_le = 0;
478 
479     if (free_slots_classic < 0){
480         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);
481         return 0;
482     }
483 
484     if (hci_stack->le_acl_packets_total_num){
485         // if we have LE slots, they are used
486         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
487         if (free_slots_le < 0){
488             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);
489             return 0;
490         }
491     } else {
492         // otherwise, classic slots are used for LE, too
493         free_slots_classic -= num_packets_sent_le;
494         if (free_slots_classic < 0){
495             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);
496             return 0;
497         }
498     }
499 
500     switch (address_type){
501         case BD_ADDR_TYPE_UNKNOWN:
502             log_error("hci_number_free_acl_slots: unknown address type");
503             return 0;
504 
505         case BD_ADDR_TYPE_ACL:
506             return free_slots_classic;
507 
508         default:
509            if (hci_stack->le_acl_packets_total_num){
510                return free_slots_le;
511            }
512            return free_slots_classic;
513     }
514 }
515 
516 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
517     // get connection type
518     hci_connection_t * connection = hci_connection_for_handle(con_handle);
519     if (!connection){
520         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
521         return 0;
522     }
523     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
524 }
525 
526 #ifdef ENABLE_CLASSIC
527 static int hci_number_free_sco_slots(void){
528     unsigned int num_sco_packets_sent  = 0;
529     btstack_linked_item_t *it;
530     if (hci_stack->synchronous_flow_control_enabled){
531         // explicit flow control
532         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
533             hci_connection_t * connection = (hci_connection_t *) it;
534             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
535             num_sco_packets_sent += connection->num_packets_sent;
536         }
537         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
538             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
539             return 0;
540         }
541         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
542     } else {
543         // implicit flow control -- TODO
544         int num_ready = 0;
545         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
546             hci_connection_t * connection = (hci_connection_t *) it;
547             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
548             if (connection->sco_tx_ready == 0) continue;
549             num_ready++;
550         }
551         return num_ready;
552     }
553 }
554 #endif
555 
556 // only used to send HCI Host Number Completed Packets
557 static int hci_can_send_comand_packet_transport(void){
558     if (hci_stack->hci_packet_buffer_reserved) return 0;
559 
560     // check for async hci transport implementations
561     if (hci_stack->hci_transport->can_send_packet_now){
562         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
563             return 0;
564         }
565     }
566     return 1;
567 }
568 
569 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
570 int hci_can_send_command_packet_now(void){
571     if (hci_can_send_comand_packet_transport() == 0) return 0;
572     return hci_stack->num_cmd_packets > 0u;
573 }
574 
575 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
576     // check for async hci transport implementations
577     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
578     return hci_stack->hci_transport->can_send_packet_now(packet_type);
579 }
580 
581 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
582     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
583     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
584 }
585 
586 int hci_can_send_acl_le_packet_now(void){
587     if (hci_stack->hci_packet_buffer_reserved) return 0;
588     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
589 }
590 
591 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
592     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
593     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
594 }
595 
596 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
597     if (hci_stack->hci_packet_buffer_reserved) return 0;
598     return hci_can_send_prepared_acl_packet_now(con_handle);
599 }
600 
601 #ifdef ENABLE_CLASSIC
602 int hci_can_send_acl_classic_packet_now(void){
603     if (hci_stack->hci_packet_buffer_reserved) return 0;
604     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
605 }
606 
607 int hci_can_send_prepared_sco_packet_now(void){
608     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
609     if (hci_have_usb_transport()){
610         return hci_stack->sco_can_send_now;
611     } else {
612         return hci_number_free_sco_slots() > 0;
613     }
614 }
615 
616 int hci_can_send_sco_packet_now(void){
617     if (hci_stack->hci_packet_buffer_reserved) return 0;
618     return hci_can_send_prepared_sco_packet_now();
619 }
620 
621 void hci_request_sco_can_send_now_event(void){
622     hci_stack->sco_waiting_for_can_send_now = 1;
623     hci_notify_if_sco_can_send_now();
624 }
625 #endif
626 
627 // used for internal checks in l2cap.c
628 int hci_is_packet_buffer_reserved(void){
629     return hci_stack->hci_packet_buffer_reserved;
630 }
631 
632 // reserves outgoing packet buffer. @returns 1 if successful
633 int hci_reserve_packet_buffer(void){
634     if (hci_stack->hci_packet_buffer_reserved) {
635         log_error("hci_reserve_packet_buffer called but buffer already reserved");
636         return 0;
637     }
638     hci_stack->hci_packet_buffer_reserved = 1;
639     return 1;
640 }
641 
642 void hci_release_packet_buffer(void){
643     hci_stack->hci_packet_buffer_reserved = 0;
644 }
645 
646 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
647 static int hci_transport_synchronous(void){
648     return hci_stack->hci_transport->can_send_packet_now == NULL;
649 }
650 
651 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
652 
653     // 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);
654 
655     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
656     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
657     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0u)){
658         max_acl_data_packet_length = hci_stack->le_data_packets_length;
659     }
660 
661 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
662     if (hci_is_le_connection(connection)){
663         max_acl_data_packet_length = connection->le_max_tx_octets;
664     }
665 #endif
666 
667     log_debug("hci_send_acl_packet_fragments entered");
668 
669     int err;
670     // multiple packets could be send on a synchronous HCI transport
671     while (true){
672 
673         log_debug("hci_send_acl_packet_fragments loop entered");
674 
675         // get current data
676         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4u;
677         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
678         int more_fragments = 0;
679 
680         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
681         if (current_acl_data_packet_length > max_acl_data_packet_length){
682             more_fragments = 1;
683             current_acl_data_packet_length = max_acl_data_packet_length;
684         }
685 
686         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
687         if (acl_header_pos > 0u){
688             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
689             handle_and_flags = (handle_and_flags & 0xcfffu) | (1u << 12u);
690             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
691         }
692 
693         // update header len
694         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2u, current_acl_data_packet_length);
695 
696         // count packet
697         connection->num_packets_sent++;
698         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
699 
700         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
701         if (more_fragments){
702             // update start of next fragment to send
703             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
704         } else {
705             // done
706             hci_stack->acl_fragmentation_pos = 0;
707             hci_stack->acl_fragmentation_total_size = 0;
708         }
709 
710         // send packet
711         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
712         const int size = current_acl_data_packet_length + 4;
713         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
714         hci_stack->acl_fragmentation_tx_active = 1;
715         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
716 
717         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
718 
719         // done yet?
720         if (!more_fragments) break;
721 
722         // can send more?
723         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
724     }
725 
726     log_debug("hci_send_acl_packet_fragments loop over");
727 
728     // release buffer now for synchronous transport
729     if (hci_transport_synchronous()){
730         hci_stack->acl_fragmentation_tx_active = 0;
731         hci_release_packet_buffer();
732         hci_emit_transport_packet_sent();
733     }
734 
735     return err;
736 }
737 
738 // pre: caller has reserved the packet buffer
739 int hci_send_acl_packet_buffer(int size){
740 
741     // log_info("hci_send_acl_packet_buffer size %u", size);
742 
743     if (!hci_stack->hci_packet_buffer_reserved) {
744         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
745         return 0;
746     }
747 
748     uint8_t * packet = hci_stack->hci_packet_buffer;
749     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
750 
751     // check for free places on Bluetooth module
752     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
753         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
754         hci_release_packet_buffer();
755         hci_emit_transport_packet_sent();
756         return BTSTACK_ACL_BUFFERS_FULL;
757     }
758 
759     hci_connection_t *connection = hci_connection_for_handle( con_handle);
760     if (!connection) {
761         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
762         hci_release_packet_buffer();
763         hci_emit_transport_packet_sent();
764         return 0;
765     }
766 
767 #ifdef ENABLE_CLASSIC
768     hci_connection_timestamp(connection);
769 #endif
770 
771     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
772 
773     // setup data
774     hci_stack->acl_fragmentation_total_size = size;
775     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
776 
777     return hci_send_acl_packet_fragments(connection);
778 }
779 
780 #ifdef ENABLE_CLASSIC
781 // pre: caller has reserved the packet buffer
782 int hci_send_sco_packet_buffer(int size){
783 
784     // log_info("hci_send_acl_packet_buffer size %u", size);
785 
786     if (!hci_stack->hci_packet_buffer_reserved) {
787         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
788         return 0;
789     }
790 
791     uint8_t * packet = hci_stack->hci_packet_buffer;
792 
793     // skip checks in loopback mode
794     if (!hci_stack->loopback_mode){
795         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
796 
797         // check for free places on Bluetooth module
798         if (!hci_can_send_prepared_sco_packet_now()) {
799             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
800             hci_release_packet_buffer();
801             hci_emit_transport_packet_sent();
802             return BTSTACK_ACL_BUFFERS_FULL;
803         }
804 
805         // track send packet in connection struct
806         hci_connection_t *connection = hci_connection_for_handle( con_handle);
807         if (!connection) {
808             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
809             hci_release_packet_buffer();
810             hci_emit_transport_packet_sent();
811             return 0;
812         }
813 
814         if (hci_have_usb_transport()){
815             // token used
816             hci_stack->sco_can_send_now = 0;
817         } else {
818             if (hci_stack->synchronous_flow_control_enabled){
819                 connection->num_packets_sent++;
820             } else {
821                 connection->sco_tx_ready--;
822             }
823         }
824     }
825 
826     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
827     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
828 
829     if (hci_transport_synchronous()){
830         hci_release_packet_buffer();
831         hci_emit_transport_packet_sent();
832     }
833 
834     return err;
835 }
836 #endif
837 
838 static void acl_handler(uint8_t *packet, uint16_t size){
839 
840     // get info
841     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
842     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
843     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
844     uint16_t acl_length         = READ_ACL_LENGTH(packet);
845 
846     // ignore non-registered handle
847     if (!conn){
848         log_error("acl_handler called with non-registered handle %u!" , con_handle);
849         return;
850     }
851 
852     // assert packet is complete
853     if ((acl_length + 4u) != size){
854         log_error("acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
855         return;
856     }
857 
858 #ifdef ENABLE_CLASSIC
859     // update idle timestamp
860     hci_connection_timestamp(conn);
861 #endif
862 
863 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
864     hci_stack->host_completed_packets = 1;
865     conn->num_packets_completed++;
866 #endif
867 
868     // handle different packet types
869     switch (acl_flags & 0x03u) {
870 
871         case 0x01: // continuation fragment
872 
873             // sanity checks
874             if (conn->acl_recombination_pos == 0u) {
875                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
876                 return;
877             }
878             if ((conn->acl_recombination_pos + acl_length) > (4u + HCI_ACL_BUFFER_SIZE)){
879                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
880                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
881                 conn->acl_recombination_pos = 0;
882                 return;
883             }
884 
885             // append fragment payload (header already stored)
886             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
887                          &packet[4], acl_length);
888             conn->acl_recombination_pos += acl_length;
889 
890             // forward complete L2CAP packet if complete.
891             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4u + 4u)){ // pos already incl. ACL header
892                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
893                 // reset recombination buffer
894                 conn->acl_recombination_length = 0;
895                 conn->acl_recombination_pos = 0;
896             }
897             break;
898 
899         case 0x02: { // first fragment
900 
901             // sanity check
902             if (conn->acl_recombination_pos) {
903                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
904                 conn->acl_recombination_pos = 0;
905             }
906 
907             // peek into L2CAP packet!
908             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
909 
910             // compare fragment size to L2CAP packet size
911             if (acl_length >= (l2cap_length + 4u)){
912                 // forward fragment as L2CAP packet
913                 hci_emit_acl_packet(packet, acl_length + 4u);
914             } else {
915 
916                 if (acl_length > HCI_ACL_BUFFER_SIZE){
917                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
918                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
919                     return;
920                 }
921 
922                 // store first fragment and tweak acl length for complete package
923                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
924                              packet, acl_length + 4u);
925                 conn->acl_recombination_pos    = acl_length + 4u;
926                 conn->acl_recombination_length = l2cap_length;
927                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2u, l2cap_length +4u);
928             }
929             break;
930 
931         }
932         default:
933             log_error( "acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
934             return;
935     }
936 
937     // execute main loop
938     hci_run();
939 }
940 
941 static void hci_shutdown_connection(hci_connection_t *conn){
942     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
943 
944 #ifdef ENABLE_CLASSIC
945 #ifdef ENABLE_SCO_OVER_HCI
946     int addr_type = conn->address_type;
947 #endif
948 #endif
949 
950     btstack_run_loop_remove_timer(&conn->timeout);
951 
952     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
953     btstack_memory_hci_connection_free( conn );
954 
955     // now it's gone
956     hci_emit_nr_connections_changed();
957 
958 #ifdef ENABLE_CLASSIC
959 #ifdef ENABLE_SCO_OVER_HCI
960     // update SCO
961     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
962         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
963     }
964 #endif
965 #endif
966 }
967 
968 #ifdef ENABLE_CLASSIC
969 
970 static const uint16_t packet_type_sizes[] = {
971     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
972     HCI_ACL_DH1_SIZE, 0, 0, 0,
973     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
974     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
975 };
976 static const uint8_t  packet_type_feature_requirement_bit[] = {
977      0, // 3 slot packets
978      1, // 5 slot packets
979     25, // EDR 2 mpbs
980     26, // EDR 3 mbps
981     39, // 3 slot EDR packts
982     40, // 5 slot EDR packet
983 };
984 static const uint16_t packet_type_feature_packet_mask[] = {
985     0x0f00, // 3 slot packets
986     0xf000, // 5 slot packets
987     0x1102, // EDR 2 mpbs
988     0x2204, // EDR 3 mbps
989     0x0300, // 3 slot EDR packts
990     0x3000, // 5 slot EDR packet
991 };
992 
993 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
994     // enable packet types based on size
995     uint16_t packet_types = 0;
996     unsigned int i;
997     for (i=0;i<16;i++){
998         if (packet_type_sizes[i] == 0) continue;
999         if (packet_type_sizes[i] <= buffer_size){
1000             packet_types |= 1 << i;
1001         }
1002     }
1003     // disable packet types due to missing local supported features
1004     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1005         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1006         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1007         if (feature_set) continue;
1008         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1009         packet_types &= ~packet_type_feature_packet_mask[i];
1010     }
1011     // flip bits for "may not be used"
1012     packet_types ^= 0x3306;
1013     return packet_types;
1014 }
1015 
1016 uint16_t hci_usable_acl_packet_types(void){
1017     return hci_stack->packet_types;
1018 }
1019 #endif
1020 
1021 uint8_t* hci_get_outgoing_packet_buffer(void){
1022     // hci packet buffer is >= acl data packet length
1023     return hci_stack->hci_packet_buffer;
1024 }
1025 
1026 uint16_t hci_max_acl_data_packet_length(void){
1027     return hci_stack->acl_data_packet_length;
1028 }
1029 
1030 #ifdef ENABLE_CLASSIC
1031 int hci_extended_sco_link_supported(void){
1032     // No. 31, byte 3, bit 7
1033     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1034 }
1035 #endif
1036 
1037 int hci_non_flushable_packet_boundary_flag_supported(void){
1038     // No. 54, byte 6, bit 6
1039     return (hci_stack->local_supported_features[6u] & (1u << 6u)) != 0u;
1040 }
1041 
1042 static int gap_ssp_supported(void){
1043     // No. 51, byte 6, bit 3
1044     return (hci_stack->local_supported_features[6u] & (1u << 3u)) != 0u;
1045 }
1046 
1047 static int hci_classic_supported(void){
1048 #ifdef ENABLE_CLASSIC
1049     // No. 37, byte 4, bit 5, = No BR/EDR Support
1050     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1051 #else
1052     return 0;
1053 #endif
1054 }
1055 
1056 static int hci_le_supported(void){
1057 #ifdef ENABLE_BLE
1058     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1059     return (hci_stack->local_supported_features[4u] & (1u << 6u)) != 0u;
1060 #else
1061     return 0;
1062 #endif
1063 }
1064 
1065 #ifdef ENABLE_BLE
1066 
1067 /**
1068  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1069  */
1070 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1071     *addr_type = hci_stack->le_own_addr_type;
1072     if (hci_stack->le_own_addr_type){
1073         (void)memcpy(addr, hci_stack->le_random_address, 6);
1074     } else {
1075         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1076     }
1077 }
1078 
1079 #ifdef ENABLE_LE_CENTRAL
1080 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1081 
1082     int offset = 3;
1083     int num_reports = packet[offset];
1084     offset += 1;
1085 
1086     int i;
1087     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1088     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1089     for (i=0; (i<num_reports) && (offset < size);i++){
1090         // sanity checks on data_length:
1091         uint8_t data_length = packet[offset + 8];
1092         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1093         if ((offset + 9u + data_length + 1u) > size)    return;
1094         // setup event
1095         uint8_t event_size = 10u + data_length;
1096         int pos = 0;
1097         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1098         event[pos++] = event_size;
1099         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1100         offset += 8;
1101         pos += 8;
1102         event[pos++] = packet[offset + 1 + data_length]; // rssi
1103         event[pos++] = data_length;
1104         offset++;
1105         (void)memcpy(&event[pos], &packet[offset], data_length);
1106         pos +=    data_length;
1107         offset += data_length + 1u; // rssi
1108         hci_emit_event(event, pos, 1);
1109     }
1110 }
1111 #endif
1112 #endif
1113 
1114 #ifdef ENABLE_BLE
1115 #ifdef ENABLE_LE_PERIPHERAL
1116 static void hci_update_advertisements_enabled_for_current_roles(void){
1117     if (hci_stack->le_advertisements_enabled){
1118         // get number of active le slave connections
1119         int num_slave_connections = 0;
1120         btstack_linked_list_iterator_t it;
1121         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1122         while (btstack_linked_list_iterator_has_next(&it)){
1123             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1124             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1125             if (con->state != OPEN) continue;
1126             if (con->role  != HCI_ROLE_SLAVE) continue;
1127             if (!hci_is_le_connection(con)) continue;
1128             num_slave_connections++;
1129         }
1130         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1131         hci_stack->le_advertisements_enabled_for_current_roles = num_slave_connections < hci_stack->le_max_number_peripheral_connections;
1132     } else {
1133         hci_stack->le_advertisements_enabled_for_current_roles = false;
1134     }
1135 }
1136 #endif
1137 #endif
1138 
1139 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1140 
1141 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1142     if (!hci_stack->config) return 0;
1143     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1144     // Limit baud rate for Broadcom chipsets to 3 mbps
1145     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1146         baud_rate = 3000000;
1147     }
1148     return baud_rate;
1149 }
1150 
1151 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1152     UNUSED(ds);
1153 
1154     switch (hci_stack->substate){
1155         case HCI_INIT_W4_SEND_RESET:
1156             log_info("Resend HCI Reset");
1157             hci_stack->substate = HCI_INIT_SEND_RESET;
1158             hci_stack->num_cmd_packets = 1;
1159             hci_run();
1160             break;
1161         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1162             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1163             if (hci_stack->hci_transport->reset_link){
1164                 hci_stack->hci_transport->reset_link();
1165             }
1166 
1167             /* fall through */
1168 
1169         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1170             log_info("Resend HCI Reset - CSR Warm Boot");
1171             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1172             hci_stack->num_cmd_packets = 1;
1173             hci_run();
1174             break;
1175         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1176             if (hci_stack->hci_transport->set_baudrate){
1177                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1178                 log_info("Local baud rate change to %" PRIu32 "(timeout handler)", baud_rate);
1179                 hci_stack->hci_transport->set_baudrate(baud_rate);
1180             }
1181             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1182             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1183                 if (hci_stack->hci_transport->reset_link){
1184                     log_info("Link Reset");
1185                     hci_stack->hci_transport->reset_link();
1186                 }
1187                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1188                 hci_run();
1189             }
1190             break;
1191         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1192             // otherwise continue
1193             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1194             hci_send_cmd(&hci_read_local_supported_commands);
1195             break;
1196         default:
1197             break;
1198     }
1199 }
1200 #endif
1201 
1202 static void hci_initializing_next_state(void){
1203     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1204 }
1205 
1206 // assumption: hci_can_send_command_packet_now() == true
1207 static void hci_initializing_run(void){
1208     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1209     switch (hci_stack->substate){
1210         case HCI_INIT_SEND_RESET:
1211             hci_state_reset();
1212 
1213 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1214             // prepare reset if command complete not received in 100ms
1215             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1216             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1217             btstack_run_loop_add_timer(&hci_stack->timeout);
1218 #endif
1219             // send command
1220             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1221             hci_send_cmd(&hci_reset);
1222             break;
1223         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1224             hci_send_cmd(&hci_read_local_version_information);
1225             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1226             break;
1227         case HCI_INIT_SEND_READ_LOCAL_NAME:
1228             hci_send_cmd(&hci_read_local_name);
1229             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1230             break;
1231 
1232 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1233         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1234             hci_state_reset();
1235             // prepare reset if command complete not received in 100ms
1236             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1237             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1238             btstack_run_loop_add_timer(&hci_stack->timeout);
1239             // send command
1240             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1241             hci_send_cmd(&hci_reset);
1242             break;
1243         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1244             hci_state_reset();
1245             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1246             hci_send_cmd(&hci_reset);
1247             break;
1248         case HCI_INIT_SEND_BAUD_CHANGE: {
1249             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1250             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1251             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1252             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1253             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1254             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1255             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1256             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1257                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1258                 btstack_run_loop_add_timer(&hci_stack->timeout);
1259             }
1260             break;
1261         }
1262         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1263             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1264             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1265             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1266             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1267             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1268             break;
1269         }
1270         case HCI_INIT_CUSTOM_INIT:
1271             // Custom initialization
1272             if (hci_stack->chipset && hci_stack->chipset->next_command){
1273                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1274                 int send_cmd = 0;
1275                 switch (hci_stack->chipset_result){
1276                     case BTSTACK_CHIPSET_VALID_COMMAND:
1277                         send_cmd = 1;
1278                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1279                         break;
1280                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1281                         send_cmd = 1;
1282                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1283                         log_info("CSR Warm Boot");
1284                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1285                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1286                         btstack_run_loop_add_timer(&hci_stack->timeout);
1287                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1288                             && hci_stack->config
1289                             && hci_stack->chipset
1290                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1291                             && hci_stack->hci_transport->set_baudrate
1292                             && hci_transport_uart_get_main_baud_rate()){
1293                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1294                         } else {
1295                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1296                         }
1297                         break;
1298                     default:
1299                         break;
1300                 }
1301 
1302                 if (send_cmd){
1303                     int size = 3u + hci_stack->hci_packet_buffer[2u];
1304                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1305                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1306                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1307                     break;
1308                 }
1309                 log_info("Init script done");
1310 
1311                 // Init script download on Broadcom chipsets causes:
1312                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1313                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1314                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1315 
1316                     // - baud rate to reset, restore UART baud rate if needed
1317                     int need_baud_change = hci_stack->config
1318                         && hci_stack->chipset
1319                         && hci_stack->chipset->set_baudrate_command
1320                         && hci_stack->hci_transport->set_baudrate
1321                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1322                     if (need_baud_change) {
1323                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1324                         log_info("Local baud rate change to %" PRIu32 " after init script (bcm)", baud_rate);
1325                         hci_stack->hci_transport->set_baudrate(baud_rate);
1326                     }
1327 
1328                     uint16_t bcm_delay_ms = 300;
1329                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1330                     //   -> Work around: wait here.
1331                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1332                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1333                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1334                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1335                     btstack_run_loop_add_timer(&hci_stack->timeout);
1336                     break;
1337                 }
1338             }
1339             // otherwise continue
1340             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1341             hci_send_cmd(&hci_read_local_supported_commands);
1342             break;
1343         case HCI_INIT_SET_BD_ADDR:
1344             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1345             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1346             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1347             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1348             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3u + hci_stack->hci_packet_buffer[2u]);
1349             break;
1350 #endif
1351 
1352         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1353             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1354             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1355             hci_send_cmd(&hci_read_local_supported_commands);
1356             break;
1357         case HCI_INIT_READ_BD_ADDR:
1358             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1359             hci_send_cmd(&hci_read_bd_addr);
1360             break;
1361         case HCI_INIT_READ_BUFFER_SIZE:
1362             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1363             hci_send_cmd(&hci_read_buffer_size);
1364             break;
1365         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1366             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1367             hci_send_cmd(&hci_read_local_supported_features);
1368             break;
1369 
1370 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1371         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1372             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1373             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1374             break;
1375         case HCI_INIT_HOST_BUFFER_SIZE:
1376             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1377             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1378                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1379             break;
1380 #endif
1381 
1382         case HCI_INIT_SET_EVENT_MASK:
1383             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1384             if (hci_le_supported()){
1385                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1386             } else {
1387                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1388                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1389             }
1390             break;
1391 
1392 #ifdef ENABLE_CLASSIC
1393         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1394             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1395             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1396             break;
1397         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1398             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1399             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1400             break;
1401         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1402             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1403             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1404             break;
1405         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1406             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1407             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1408             break;
1409         case HCI_INIT_WRITE_LOCAL_NAME: {
1410             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1411             hci_reserve_packet_buffer();
1412             uint8_t * packet = hci_stack->hci_packet_buffer;
1413             // construct HCI Command and send
1414             uint16_t opcode = hci_write_local_name.opcode;
1415             hci_stack->last_cmd_opcode = opcode;
1416             packet[0] = opcode & 0xff;
1417             packet[1] = opcode >> 8;
1418             packet[2] = DEVICE_NAME_LEN;
1419             memset(&packet[3], 0, DEVICE_NAME_LEN);
1420             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1421             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1422             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1423             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1424             // expand '00:00:00:00:00:00' in name with bd_addr
1425             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1426             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1427             break;
1428         }
1429         case HCI_INIT_WRITE_EIR_DATA: {
1430             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1431             hci_reserve_packet_buffer();
1432             uint8_t * packet = hci_stack->hci_packet_buffer;
1433             // construct HCI Command in-place and send
1434             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1435             hci_stack->last_cmd_opcode = opcode;
1436             uint16_t offset = 0;
1437             packet[offset++] = opcode & 0xff;
1438             packet[offset++] = opcode >> 8;
1439             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1440             packet[offset++] = 0;  // FEC not required
1441             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1442             if (hci_stack->eir_data){
1443                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1444                 ad_context_t context;
1445                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1446                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1447                     uint8_t size        = ad_iterator_get_data_len(&context);
1448                     const uint8_t *data = ad_iterator_get_data(&context);
1449                     // copy item
1450                     packet[offset++] = size + 1;
1451                     packet[offset++] = data_type;
1452                     memcpy(&packet[offset], data, size);
1453                     // update name item
1454                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1455                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1456                     }
1457                     offset += size;
1458                 }
1459             } else {
1460                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1461                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1462                 packet[offset++] = bytes_to_copy + 1;
1463                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1464                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1465                 // expand '00:00:00:00:00:00' in name with bd_addr
1466                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1467             }
1468             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1469             break;
1470         }
1471         case HCI_INIT_WRITE_INQUIRY_MODE:
1472             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1473             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1474             break;
1475         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1476             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1477             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1478             break;
1479         case HCI_INIT_WRITE_SCAN_ENABLE:
1480             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1481             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1482             break;
1483         // only sent if ENABLE_SCO_OVER_HCI is defined
1484         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1485             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1486             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1487             break;
1488         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1489             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1490             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1491             break;
1492         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1493         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1494             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1495             log_info("BCM: Route SCO data via HCI transport");
1496             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1497             break;
1498 
1499 #endif
1500 #ifdef ENABLE_BLE
1501         // LE INIT
1502         case HCI_INIT_LE_READ_BUFFER_SIZE:
1503             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1504             hci_send_cmd(&hci_le_read_buffer_size);
1505             break;
1506         case HCI_INIT_LE_SET_EVENT_MASK:
1507             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1508             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1509             break;
1510         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1511             // LE Supported Host = 1, Simultaneous Host = 0
1512             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1513             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1514             break;
1515 #endif
1516 
1517 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1518         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1519             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1520             hci_send_cmd(&hci_le_read_maximum_data_length);
1521             break;
1522         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1523             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1524             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1525             break;
1526 #endif
1527 
1528 #ifdef ENABLE_LE_CENTRAL
1529         case HCI_INIT_READ_WHITE_LIST_SIZE:
1530             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1531             hci_send_cmd(&hci_le_read_white_list_size);
1532             break;
1533         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1534             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1535             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);
1536             break;
1537 #endif
1538         default:
1539             return;
1540     }
1541 }
1542 
1543 static void hci_init_done(void){
1544     // done. tell the app
1545     log_info("hci_init_done -> HCI_STATE_WORKING");
1546     hci_stack->state = HCI_STATE_WORKING;
1547     hci_emit_state();
1548     hci_run();
1549 }
1550 
1551 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1552     bool command_completed = false;
1553     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1554         uint16_t opcode = little_endian_read_16(packet,3);
1555         if (opcode == hci_stack->last_cmd_opcode){
1556             command_completed = true;
1557             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1558         } else {
1559             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1560         }
1561     }
1562 
1563     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1564         uint8_t  status = packet[2];
1565         uint16_t opcode = little_endian_read_16(packet,4);
1566         if (opcode == hci_stack->last_cmd_opcode){
1567             if (status){
1568                 command_completed = true;
1569                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1570             } else {
1571                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1572             }
1573         } else {
1574             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1575         }
1576     }
1577 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1578     // Vendor == CSR
1579     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1580         // TODO: track actual command
1581         command_completed = true;
1582     }
1583 
1584     // Vendor == Toshiba
1585     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1586         // TODO: track actual command
1587         command_completed = true;
1588         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1589         hci_stack->num_cmd_packets = 1;
1590     }
1591 #endif
1592 
1593     return command_completed;
1594 }
1595 
1596 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1597 
1598     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1599 
1600     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1601 
1602 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1603 
1604     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1605     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1606     //
1607     // HCI Reset
1608     // Timeout 100 ms
1609     // HCI Reset
1610     // Command Complete Reset
1611     // HCI Read Local Version Information
1612     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1613     // hang...
1614     //
1615     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1616     if (!command_completed
1617             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1618             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1619 
1620         uint16_t opcode = little_endian_read_16(packet,3);
1621         if (opcode == hci_reset.opcode){
1622             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1623             return;
1624         }
1625     }
1626 
1627     // CSR & H5
1628     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1629     if (!command_completed
1630             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1631             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1632 
1633         uint16_t opcode = little_endian_read_16(packet,3);
1634         if (opcode == hci_reset.opcode){
1635             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1636             return;
1637         }
1638     }
1639 
1640     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1641     // fix: Correct substate and behave as command below
1642     if (command_completed){
1643         switch (hci_stack->substate){
1644             case HCI_INIT_SEND_RESET:
1645                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1646                 break;
1647             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1648                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1649                 break;
1650             default:
1651                 break;
1652         }
1653     }
1654 
1655 #endif
1656 
1657     if (!command_completed) return;
1658 
1659     bool need_baud_change = false;
1660     bool need_addr_change = false;
1661 
1662 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1663     need_baud_change = hci_stack->config
1664                         && hci_stack->chipset
1665                         && hci_stack->chipset->set_baudrate_command
1666                         && hci_stack->hci_transport->set_baudrate
1667                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1668 
1669     need_addr_change = hci_stack->custom_bd_addr_set
1670                         && hci_stack->chipset
1671                         && hci_stack->chipset->set_bd_addr_command;
1672 #endif
1673 
1674     switch(hci_stack->substate){
1675 
1676 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1677         case HCI_INIT_SEND_RESET:
1678             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1679             // fix: just correct substate and behave as command below
1680             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1681             btstack_run_loop_remove_timer(&hci_stack->timeout);
1682             break;
1683         case HCI_INIT_W4_SEND_RESET:
1684             btstack_run_loop_remove_timer(&hci_stack->timeout);
1685             break;
1686         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1687             log_info("Received local name, need baud change %d", (int) need_baud_change);
1688             if (need_baud_change){
1689                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1690                 return;
1691             }
1692             // skip baud change
1693             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1694             return;
1695         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1696             // for STLC2500D, baud rate change already happened.
1697             // for others, baud rate gets changed now
1698             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1699                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1700                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change)", baud_rate);
1701                 hci_stack->hci_transport->set_baudrate(baud_rate);
1702             }
1703             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1704             return;
1705         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1706             btstack_run_loop_remove_timer(&hci_stack->timeout);
1707             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1708             return;
1709         case HCI_INIT_W4_CUSTOM_INIT:
1710             // repeat custom init
1711             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1712             return;
1713 #else
1714         case HCI_INIT_W4_SEND_RESET:
1715             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1716             return ;
1717 #endif
1718 
1719         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1720             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1721               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1722                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1723                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1724                 return;
1725             }
1726             if (need_addr_change){
1727                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1728                 return;
1729             }
1730             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1731             return;
1732 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1733         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1734             if (need_baud_change){
1735                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1736                 log_info("Local baud rate change to %" PRIu32 "(w4_send_baud_change_bcm))", baud_rate);
1737                 hci_stack->hci_transport->set_baudrate(baud_rate);
1738             }
1739             if (need_addr_change){
1740                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1741                 return;
1742             }
1743             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1744             return;
1745         case HCI_INIT_W4_SET_BD_ADDR:
1746             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1747             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1748             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1749                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1750                 return;
1751             }
1752             // skipping st warm boot
1753             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1754             return;
1755         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1756             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1757             return;
1758 #endif
1759         case HCI_INIT_W4_READ_BD_ADDR:
1760             // only read buffer size if supported
1761             if (hci_stack->local_supported_commands[0u] & 0x01u) {
1762                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1763                 return;
1764             }
1765             // skipping read buffer size
1766             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1767             return;
1768         case HCI_INIT_W4_SET_EVENT_MASK:
1769             // skip Classic init commands for LE only chipsets
1770             if (!hci_classic_supported()){
1771 #ifdef ENABLE_BLE
1772                 if (hci_le_supported()){
1773                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1774                     return;
1775                 }
1776 #endif
1777                 log_error("Neither BR/EDR nor LE supported");
1778                 hci_init_done();
1779                 return;
1780             }
1781             if (!gap_ssp_supported()){
1782                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1783                 return;
1784             }
1785             break;
1786 #ifdef ENABLE_BLE
1787         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1788             // skip write le host if not supported (e.g. on LE only EM9301)
1789             if (hci_stack->local_supported_commands[0u] & 0x02u) break;
1790             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1791             return;
1792 
1793 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1794         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1795             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1796             if ((hci_stack->local_supported_commands[0u] & 0x30u) == 0x30u){
1797                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1798                 return;
1799             }
1800             // explicit fall through to reduce repetitions
1801 
1802 #ifdef ENABLE_LE_CENTRAL
1803             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1804 #else
1805             hci_init_done();
1806 #endif
1807             return;
1808 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1809 
1810 #endif  /* ENABLE_BLE */
1811 
1812         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1813             // skip write secure connections host support if not supported or disabled
1814             if (!hci_stack->secure_connections_enable || (hci_stack->local_supported_commands[1u] & 0x02u) == 0u) {
1815                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1816                 return;
1817             }
1818             break;
1819 
1820 #ifdef ENABLE_SCO_OVER_HCI
1821         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1822             // skip write synchronous flow control if not supported
1823             if (hci_stack->local_supported_commands[0] & 0x04) break;
1824             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1825 
1826             /* fall through */
1827 
1828         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1829             // skip write default erroneous data reporting if not supported
1830             if (hci_stack->local_supported_commands[0] & 0x08) break;
1831             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1832 
1833             /* fall through */
1834 
1835         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1836             // skip bcm set sco pcm config on non-Broadcom chipsets
1837             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1838             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1839 
1840             /* fall through */
1841 
1842         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1843             if (!hci_le_supported()){
1844                 // SKIP LE init for Classic only configuration
1845                 hci_init_done();
1846                 return;
1847             }
1848             break;
1849 
1850 #else /* !ENABLE_SCO_OVER_HCI */
1851 
1852         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1853 #ifdef ENABLE_BLE
1854             if (hci_le_supported()){
1855                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1856                 return;
1857             }
1858 #endif
1859             // SKIP LE init for Classic only configuration
1860             hci_init_done();
1861             return;
1862 #endif /* ENABLE_SCO_OVER_HCI */
1863 
1864 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1865 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1866         // Response to command before init done state -> init done
1867         case (HCI_INIT_DONE-1):
1868             hci_init_done();
1869             return;
1870 #endif
1871 
1872         default:
1873             break;
1874     }
1875     hci_initializing_next_state();
1876 }
1877 
1878 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1879     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1880     bd_addr_t bd_address;
1881     (void)memcpy(&bd_address, conn->address, 6);
1882 
1883 #ifdef ENABLE_CLASSIC
1884     // cache needed data
1885     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1886 #endif
1887 
1888     // connection failed, remove entry
1889     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1890     btstack_memory_hci_connection_free( conn );
1891 
1892 #ifdef ENABLE_CLASSIC
1893     // notify client if dedicated bonding
1894     if (notify_dedicated_bonding_failed){
1895         log_info("hci notify_dedicated_bonding_failed");
1896         hci_emit_dedicated_bonding_result(bd_address, status);
1897     }
1898 
1899     // if authentication error, also delete link key
1900     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1901         gap_drop_link_key_for_bd_addr(bd_address);
1902     }
1903 #else
1904     UNUSED(status);
1905 #endif
1906 }
1907 
1908 #ifdef ENABLE_CLASSIC
1909 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1910     // SSP Controller
1911     if (features[6] & (1 << 3)){
1912         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1913     }
1914     // eSCO
1915     if (features[3] & (1<<7)){
1916         conn->remote_supported_features[0] |= 1;
1917     }
1918     // Extended features
1919     if (features[7] & (1<<7)){
1920         conn->remote_supported_features[0] |= 2;
1921     }
1922 }
1923 
1924 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1925     // SSP Host
1926     if (features[0] & (1 << 0)){
1927         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1928     }
1929     // SC Host
1930     if (features[0] & (1 << 3)){
1931         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1932     }
1933 }
1934 
1935 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1936     // SC Controller
1937     if (features[1] & (1 << 0)){
1938         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1939     }
1940 }
1941 
1942 static void hci_handle_remote_features_received(hci_connection_t * conn){
1943     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1944     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1945     if (conn->bonding_flags & BONDING_DEDICATED){
1946         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1947     }
1948 }
1949 #endif
1950 
1951 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1952     // handle BT initialization
1953     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1954         hci_initializing_event_handler(packet, size);
1955     }
1956 
1957     // help with BT sleep
1958     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1959         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1960         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1961         hci_initializing_next_state();
1962     }
1963 }
1964 
1965 #ifdef ENABLE_CLASSIC
1966 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1967     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1968     conn->encryption_key_size = encryption_key_size;
1969 
1970     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1971         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1972         return;
1973     }
1974 
1975     // Request Authentication if not already done
1976     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1977     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1978 }
1979 #endif
1980 
1981 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1982     UNUSED(size);
1983 
1984     uint16_t manufacturer;
1985 #ifdef ENABLE_CLASSIC
1986     hci_con_handle_t handle;
1987     hci_connection_t * conn;
1988     uint8_t status;
1989 #endif
1990     // get num cmd packets - limit to 1 to reduce complexity
1991     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1992 
1993     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
1994     switch (opcode){
1995         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
1996             if (packet[5]) break;
1997             // terminate, name 248 chars
1998             packet[6+248] = 0;
1999             log_info("local name: %s", &packet[6]);
2000             break;
2001         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2002             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2003             if (hci_stack->state == HCI_STATE_INITIALIZING) {
2004                 uint16_t acl_len = little_endian_read_16(packet, 6);
2005                 uint16_t sco_len = packet[8];
2006 
2007                 // determine usable ACL/SCO payload size
2008                 hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2009                 hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2010 
2011                 hci_stack->acl_packets_total_num = little_endian_read_16(packet, 9);
2012                 hci_stack->sco_packets_total_num = little_endian_read_16(packet, 11);
2013 
2014                 log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2015                          acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2016                          hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2017             }
2018             break;
2019         case HCI_OPCODE_HCI_READ_RSSI:
2020             if (packet[5] == ERROR_CODE_SUCCESS){
2021                 uint8_t event[5];
2022                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2023                 event[1] = 3;
2024                 (void)memcpy(&event[2], &packet[6], 3);
2025                 hci_emit_event(event, sizeof(event), 1);
2026             }
2027             break;
2028 #ifdef ENABLE_BLE
2029         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2030             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2031             hci_stack->le_acl_packets_total_num = packet[8];
2032             // determine usable ACL payload size
2033             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2034                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2035             }
2036             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2037             break;
2038 #endif
2039 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2040         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2041             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2042             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2043             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);
2044             break;
2045 #endif
2046 #ifdef ENABLE_LE_CENTRAL
2047         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2048             hci_stack->le_whitelist_capacity = packet[6];
2049             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2050             break;
2051 #endif
2052         case HCI_OPCODE_HCI_READ_BD_ADDR:
2053             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2054             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));
2055 #ifdef ENABLE_CLASSIC
2056             if (hci_stack->link_key_db){
2057                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2058             }
2059 #endif
2060             break;
2061 #ifdef ENABLE_CLASSIC
2062         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2063             hci_emit_discoverable_enabled(hci_stack->discoverable);
2064             break;
2065         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2066             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2067                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2068                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2069                 hci_emit_event(event, sizeof(event), 1);
2070             }
2071             break;
2072 #endif
2073         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2074             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2075 
2076 #ifdef ENABLE_CLASSIC
2077             // determine usable ACL packet types based on host buffer size and supported features
2078             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2079             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2080 #endif
2081             // Classic/LE
2082             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2083             break;
2084         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2085             manufacturer = little_endian_read_16(packet, 10);
2086             // map Cypress to Broadcom
2087             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2088                 log_info("Treat Cypress as Broadcom");
2089                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2090                 little_endian_store_16(packet, 10, manufacturer);
2091             }
2092             hci_stack->manufacturer = manufacturer;
2093             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2094             break;
2095         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2096             hci_stack->local_supported_commands[0] =
2097                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+14u] & 0x80u) >> 7u) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2098                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+24u] & 0x40u) >> 5u) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2099                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+10u] & 0x10u) >> 2u) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2100                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+18u] & 0x08u)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2101                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+34u] & 0x01u) << 4u) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2102                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x08u) << 2u) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2103                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+35u] & 0x20u) << 1u) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2104                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+20u] & 0x10u) << 3u);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2105             hci_stack->local_supported_commands[1] =
2106                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+ 2u] & 0x40u) >> 6u) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2107                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1u+32u] & 0x08u) >> 2u);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2108             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2109             break;
2110 #ifdef ENABLE_CLASSIC
2111         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2112             if (packet[5]) return;
2113             hci_stack->synchronous_flow_control_enabled = 1;
2114             break;
2115         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2116             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2117             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2118             conn   = hci_connection_for_handle(handle);
2119             if (conn != NULL) {
2120                 uint8_t key_size = 0;
2121                 if (status == 0){
2122                     key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2123                     log_info("Handle %04x key Size: %u", handle, key_size);
2124                 } else {
2125                     log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2126                 }
2127                 hci_handle_read_encryption_key_size_complete(conn, key_size);
2128             }
2129             break;
2130 #endif
2131         default:
2132             break;
2133     }
2134 }
2135 
2136 static void event_handler(uint8_t *packet, uint16_t size){
2137 
2138     uint16_t event_length = packet[1];
2139 
2140     // assert packet is complete
2141     if (size != (event_length + 2u)){
2142         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2143         return;
2144     }
2145 
2146     bd_addr_t addr;
2147     bd_addr_type_t addr_type;
2148     hci_con_handle_t handle;
2149     hci_connection_t * conn;
2150     int i;
2151     int create_connection_cmd;
2152 
2153 #ifdef ENABLE_CLASSIC
2154     uint8_t link_type;
2155 #endif
2156 
2157     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2158 
2159     switch (hci_event_packet_get_type(packet)) {
2160 
2161         case HCI_EVENT_COMMAND_COMPLETE:
2162             handle_command_complete_event(packet, size);
2163             break;
2164 
2165         case HCI_EVENT_COMMAND_STATUS:
2166             // get num cmd packets - limit to 1 to reduce complexity
2167             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2168 
2169             // check command status to detected failed outgoing connections
2170             create_connection_cmd = 0;
2171 #ifdef ENABLE_CLASSIC
2172             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2173                 create_connection_cmd = 1;
2174             }
2175 #endif
2176 #ifdef ENABLE_LE_CENTRAL
2177             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2178                 create_connection_cmd = 1;
2179             }
2180 #endif
2181             if (create_connection_cmd) {
2182                 uint8_t status = hci_event_command_status_get_status(packet);
2183                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2184                 log_info("command status (create connection), status %x, connection %p, addr %s, type %x", status, conn, bd_addr_to_str(hci_stack->outgoing_addr), hci_stack->outgoing_addr_type);
2185 
2186                 // reset outgoing address info
2187                 memset(hci_stack->outgoing_addr, 0, 6);
2188                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2189 
2190                 // error => outgoing connection failed
2191                 if ((conn != NULL) && (status != 0u)){
2192                     hci_handle_connection_failed(conn, status);
2193                 }
2194             }
2195             break;
2196 
2197         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2198             if (size < 3) return;
2199             uint16_t num_handles = packet[2];
2200             if (size != (3u + num_handles * 4u)) return;
2201             uint16_t offset = 3;
2202             for (i=0; i<num_handles;i++){
2203                 handle = little_endian_read_16(packet, offset) & 0x0fffu;
2204                 offset += 2u;
2205                 uint16_t num_packets = little_endian_read_16(packet, offset);
2206                 offset += 2u;
2207 
2208                 conn = hci_connection_for_handle(handle);
2209                 if (!conn){
2210                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2211                     continue;
2212                 }
2213 
2214                 if (conn->num_packets_sent >= num_packets){
2215                     conn->num_packets_sent -= num_packets;
2216                 } else {
2217                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2218                     conn->num_packets_sent = 0;
2219                 }
2220                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2221 
2222 #ifdef ENABLE_CLASSIC
2223                 // For SCO, we do the can_send_now_check here
2224                 hci_notify_if_sco_can_send_now();
2225 #endif
2226             }
2227             break;
2228         }
2229 
2230 #ifdef ENABLE_CLASSIC
2231         case HCI_EVENT_INQUIRY_COMPLETE:
2232             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2233                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2234                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2235                 hci_emit_event(event, sizeof(event), 1);
2236             }
2237             break;
2238         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2239             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2240                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2241             }
2242             break;
2243         case HCI_EVENT_CONNECTION_REQUEST:
2244             reverse_bd_addr(&packet[2], addr);
2245             if (hci_stack->gap_classic_accept_callback != NULL){
2246                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2247                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2248                     bd_addr_copy(hci_stack->decline_addr, addr);
2249                     break;
2250                 }
2251             }
2252 
2253             // TODO: eval COD 8-10
2254             link_type = packet[11];
2255             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2256             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2257             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2258             if (!conn) {
2259                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2260             }
2261             if (!conn) {
2262                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2263                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2264                 bd_addr_copy(hci_stack->decline_addr, addr);
2265                 break;
2266             }
2267             conn->role  = HCI_ROLE_SLAVE;
2268             conn->state = RECEIVED_CONNECTION_REQUEST;
2269             // store info about eSCO
2270             if (link_type == 0x02){
2271                 conn->remote_supported_features[0] |= 1;
2272             }
2273             hci_run();
2274             break;
2275 
2276         case HCI_EVENT_CONNECTION_COMPLETE:
2277             // Connection management
2278             reverse_bd_addr(&packet[5], addr);
2279             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2280             addr_type = BD_ADDR_TYPE_ACL;
2281             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2282             if (conn) {
2283                 if (!packet[2]){
2284                     conn->state = OPEN;
2285                     conn->con_handle = little_endian_read_16(packet, 3);
2286 
2287                     // queue get remote feature
2288                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2289 
2290                     // queue set supervision timeout if we're master
2291                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2292                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2293                     }
2294 
2295                     // restart timer
2296                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2297                     btstack_run_loop_add_timer(&conn->timeout);
2298 
2299                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2300 
2301                     hci_emit_nr_connections_changed();
2302                 } else {
2303                     // connection failed
2304                     hci_handle_connection_failed(conn, packet[2]);
2305                 }
2306             }
2307             break;
2308 
2309         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2310             reverse_bd_addr(&packet[5], addr);
2311             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2312             if (packet[2]){
2313                 // connection failed
2314                 break;
2315             }
2316             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2317             if (!conn) {
2318                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2319             }
2320             if (!conn) {
2321                 break;
2322             }
2323             conn->state = OPEN;
2324             conn->con_handle = little_endian_read_16(packet, 3);
2325 
2326 #ifdef ENABLE_SCO_OVER_HCI
2327             // update SCO
2328             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2329                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2330             }
2331             // trigger can send now
2332             if (hci_have_usb_transport()){
2333                 hci_stack->sco_can_send_now = 1;
2334             }
2335 #endif
2336             break;
2337 
2338         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2339             handle = little_endian_read_16(packet, 3);
2340             conn = hci_connection_for_handle(handle);
2341             if (!conn) break;
2342             if (!packet[2]){
2343                 const uint8_t * features = &packet[5];
2344                 hci_handle_remote_features_page_0(conn, features);
2345 
2346                 // read extended features if possible
2347                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2348                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2349                     break;
2350                 }
2351             }
2352             hci_handle_remote_features_received(conn);
2353             break;
2354 
2355         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2356             handle = little_endian_read_16(packet, 3);
2357             conn = hci_connection_for_handle(handle);
2358             if (!conn) break;
2359             // status = ok, page = 1
2360             if (!packet[2]) {
2361                 uint8_t page_number = packet[5];
2362                 uint8_t maximum_page_number = packet[6];
2363                 const uint8_t * features = &packet[7];
2364                 bool done = false;
2365                 switch (page_number){
2366                     case 1:
2367                         hci_handle_remote_features_page_1(conn, features);
2368                         if (maximum_page_number >= 2){
2369                             // get Secure Connections (Controller) from Page 2 if available
2370                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2371                         } else {
2372                             // otherwise, assume SC (Controller) == SC (Host)
2373                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2374                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2375                             }
2376                             done = true;
2377                         }
2378                         break;
2379                     case 2:
2380                         hci_handle_remote_features_page_2(conn, features);
2381                         done = true;
2382                         break;
2383                     default:
2384                         break;
2385                 }
2386                 if (!done) break;
2387             }
2388             hci_handle_remote_features_received(conn);
2389             break;
2390 
2391         case HCI_EVENT_LINK_KEY_REQUEST:
2392             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2393             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2394             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2395             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2396             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2397             hci_run();
2398             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2399             return;
2400 
2401         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2402             reverse_bd_addr(&packet[2], addr);
2403             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2404             if (!conn) break;
2405             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2406             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2407             // Change Connection Encryption keeps link key type
2408             if (link_key_type != CHANGED_COMBINATION_KEY){
2409                 conn->link_key_type = link_key_type;
2410             }
2411             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2412             // still forward event to allow dismiss of pairing dialog
2413             break;
2414         }
2415 
2416         case HCI_EVENT_PIN_CODE_REQUEST:
2417             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2418             // non-bondable mode: pin code negative reply will be sent
2419             if (!hci_stack->bondable){
2420                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2421                 hci_run();
2422                 return;
2423             }
2424             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2425             if (!hci_stack->link_key_db) break;
2426             hci_event_pin_code_request_get_bd_addr(packet, addr);
2427             hci_stack->link_key_db->delete_link_key(addr);
2428             break;
2429 
2430         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2431             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2432             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2433             break;
2434 
2435         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2436             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2437             if (!hci_stack->ssp_auto_accept) break;
2438             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2439             break;
2440 
2441         case HCI_EVENT_USER_PASSKEY_REQUEST:
2442             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2443             if (!hci_stack->ssp_auto_accept) break;
2444             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2445             break;
2446         case HCI_EVENT_MODE_CHANGE:
2447             handle = hci_event_mode_change_get_handle(packet);
2448             conn = hci_connection_for_handle(handle);
2449             if (!conn) break;
2450             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2451             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2452             break;
2453 #endif
2454 
2455         case HCI_EVENT_ENCRYPTION_CHANGE:
2456             handle = hci_event_encryption_change_get_connection_handle(packet);
2457             conn = hci_connection_for_handle(handle);
2458             if (!conn) break;
2459             if (hci_event_encryption_change_get_status(packet) == 0u) {
2460                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2461                 if (encryption_enabled){
2462                     if (hci_is_le_connection(conn)){
2463                         // For LE, we accept connection as encrypted
2464                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2465                     }
2466 #ifdef ENABLE_CLASSIC
2467                     else {
2468                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2469                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2470                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2471                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2472                             log_info("SC during pairing, but only E0 now -> abort");
2473                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2474                             break;
2475                         }
2476 
2477                         // if AES-CCM is used, authentication used SC -> authentication was mutual and we can skip explicit authentication
2478                         if (connected_uses_aes_ccm){
2479                             conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2480                         }
2481 
2482                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2483                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2484                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2485                         } else {
2486                             // if not, pretend everything is perfect
2487                             hci_handle_read_encryption_key_size_complete(conn, 16);
2488                         }
2489                     }
2490 #endif
2491                 } else {
2492                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2493                 }
2494             }
2495 
2496             break;
2497 
2498 #ifdef ENABLE_CLASSIC
2499         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2500             handle = hci_event_authentication_complete_get_connection_handle(packet);
2501             conn = hci_connection_for_handle(handle);
2502             if (!conn) break;
2503 
2504             // ignore authentication event if we didn't request it
2505             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2506 
2507             // dedicated bonding: send result and disconnect
2508             if (conn->bonding_flags & BONDING_DEDICATED){
2509                 conn->bonding_flags &= ~BONDING_DEDICATED;
2510                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2511                 conn->bonding_status = packet[2];
2512                 break;
2513             }
2514 
2515             // authenticated only if auth status == 0
2516             if (hci_event_authentication_complete_get_status(packet) == 0){
2517                 // authenticated
2518                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2519 
2520                 // If link key sufficient for requested security and not already encrypted, start encryption
2521                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2522                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2523                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2524                     break;
2525                 }
2526             }
2527 
2528             // emit updated security level
2529             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2530             break;
2531 #endif
2532 
2533         // HCI_EVENT_DISCONNECTION_COMPLETE
2534         // has been split, to first notify stack before shutting connection down
2535         // see end of function, too.
2536         case HCI_EVENT_DISCONNECTION_COMPLETE:
2537             if (packet[2]) break;   // status != 0
2538             handle = little_endian_read_16(packet, 3);
2539             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2540             if (hci_stack->acl_fragmentation_total_size > 0u) {
2541                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2542                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0u;
2543                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2544                     hci_stack->acl_fragmentation_total_size = 0;
2545                     hci_stack->acl_fragmentation_pos = 0;
2546                     if (release_buffer){
2547                         hci_release_packet_buffer();
2548                     }
2549                 }
2550             }
2551 
2552             conn = hci_connection_for_handle(handle);
2553             if (!conn) break;
2554             // mark connection for shutdown
2555             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2556 
2557             // emit dedicatd bonding event
2558             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2559                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2560             }
2561 
2562 #ifdef ENABLE_BLE
2563 #ifdef ENABLE_LE_PERIPHERAL
2564             // re-enable advertisements for le connections if active
2565             if (hci_is_le_connection(conn)){
2566                 hci_update_advertisements_enabled_for_current_roles();
2567             }
2568 #endif
2569 #endif
2570             break;
2571 
2572         case HCI_EVENT_HARDWARE_ERROR:
2573             log_error("Hardware Error: 0x%02x", packet[2]);
2574             if (hci_stack->hardware_error_callback){
2575                 (*hci_stack->hardware_error_callback)(packet[2]);
2576             } else {
2577                 // if no special requests, just reboot stack
2578                 hci_power_control_off();
2579                 hci_power_control_on();
2580             }
2581             break;
2582 
2583 #ifdef ENABLE_CLASSIC
2584         case HCI_EVENT_ROLE_CHANGE:
2585             if (packet[2]) break;   // status != 0
2586             reverse_bd_addr(&packet[3], addr);
2587             addr_type = BD_ADDR_TYPE_ACL;
2588             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2589             if (!conn) break;
2590             conn->role = packet[9];
2591             break;
2592 #endif
2593 
2594         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2595             // release packet buffer only for asynchronous transport and if there are not further fragements
2596             if (hci_transport_synchronous()) {
2597                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2598                 return; // instead of break: to avoid re-entering hci_run()
2599             }
2600             hci_stack->acl_fragmentation_tx_active = 0;
2601             if (hci_stack->acl_fragmentation_total_size) break;
2602             hci_release_packet_buffer();
2603 
2604             // L2CAP receives this event via the hci_emit_event below
2605 
2606 #ifdef ENABLE_CLASSIC
2607             // For SCO, we do the can_send_now_check here
2608             hci_notify_if_sco_can_send_now();
2609 #endif
2610             break;
2611 
2612 #ifdef ENABLE_CLASSIC
2613         case HCI_EVENT_SCO_CAN_SEND_NOW:
2614             // For SCO, we do the can_send_now_check here
2615             hci_stack->sco_can_send_now = 1;
2616             hci_notify_if_sco_can_send_now();
2617             return;
2618 
2619         // explode inquriy results for easier consumption
2620         case HCI_EVENT_INQUIRY_RESULT:
2621         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2622         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2623             gap_inquiry_explode(packet, size);
2624             break;
2625 #endif
2626 
2627 #ifdef ENABLE_BLE
2628         case HCI_EVENT_LE_META:
2629             switch (packet[2]){
2630 #ifdef ENABLE_LE_CENTRAL
2631                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2632                     // log_info("advertising report received");
2633                     if (!hci_stack->le_scanning_enabled) break;
2634                     le_handle_advertisement_report(packet, size);
2635                     break;
2636 #endif
2637                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2638                     // Connection management
2639                     reverse_bd_addr(&packet[8], addr);
2640                     addr_type = (bd_addr_type_t)packet[7];
2641                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2642                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2643 
2644 #ifdef ENABLE_LE_CENTRAL
2645                     // handle error: error is reported only to the initiator -> outgoing connection
2646                     if (packet[3]){
2647 
2648                         // handle cancelled outgoing connection
2649                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2650                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2651                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2652                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2653                             conn = gap_get_outgoing_connection();
2654                         }
2655 
2656                         // remove entry
2657                         if (conn){
2658                             // outgoing le connection establishment is done
2659                             if (hci_is_le_connection(conn)){
2660                                 hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2661                                 hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2662                             }
2663                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2664                             btstack_memory_hci_connection_free( conn );
2665                         }
2666                         break;
2667                     }
2668 #endif
2669 
2670                     // on success, both hosts receive connection complete event
2671                     if (packet[6] == HCI_ROLE_MASTER){
2672 #ifdef ENABLE_LE_CENTRAL
2673                         // if we're master on an le connection, it was an outgoing connection and we're done with it
2674                         // note: no hci_connection_t object exists yet for connect with whitelist
2675                         if (hci_is_le_connection_type(addr_type)){
2676                             hci_stack->le_connecting_state   = LE_CONNECTING_IDLE;
2677                             hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2678                         }
2679 #endif
2680                     } else {
2681 #ifdef ENABLE_LE_PERIPHERAL
2682                         // if we're slave, it was an incoming connection, advertisements have stopped
2683                         hci_stack->le_advertisements_active = 0;
2684 #endif
2685                     }
2686                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2687                     if (!conn){
2688                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2689                     }
2690                     // no memory, sorry.
2691                     if (!conn){
2692                         break;
2693                     }
2694 
2695                     conn->state = OPEN;
2696                     conn->role  = packet[6];
2697                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2698                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2699 
2700 #ifdef ENABLE_LE_PERIPHERAL
2701                     if (packet[6] == HCI_ROLE_SLAVE){
2702                         hci_update_advertisements_enabled_for_current_roles();
2703                     }
2704 #endif
2705 
2706                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2707 
2708                     // restart timer
2709                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2710                     // btstack_run_loop_add_timer(&conn->timeout);
2711 
2712                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2713 
2714                     hci_emit_nr_connections_changed();
2715                     break;
2716 
2717                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2718                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2719                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2720                     conn = hci_connection_for_handle(handle);
2721                     if (!conn) break;
2722                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2723                     break;
2724 
2725                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2726                     // connection
2727                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2728                     conn = hci_connection_for_handle(handle);
2729                     if (conn) {
2730                         // read arguments
2731                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2732                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2733                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2734                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2735 
2736                         // validate against current connection parameter range
2737                         le_connection_parameter_range_t existing_range;
2738                         gap_get_connection_parameter_range(&existing_range);
2739                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2740                         if (update_parameter){
2741                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2742                             conn->le_conn_interval_min = le_conn_interval_min;
2743                             conn->le_conn_interval_max = le_conn_interval_max;
2744                             conn->le_conn_latency = le_conn_latency;
2745                             conn->le_supervision_timeout = le_supervision_timeout;
2746                         } else {
2747                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2748                         }
2749                     }
2750                     break;
2751 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2752                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2753                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2754                     conn = hci_connection_for_handle(handle);
2755                     if (conn) {
2756                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2757                     }
2758                     break;
2759 #endif
2760                 default:
2761                     break;
2762             }
2763             break;
2764 #endif
2765         case HCI_EVENT_VENDOR_SPECIFIC:
2766             // Vendor specific commands often create vendor specific event instead of num completed packets
2767             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2768             switch (hci_stack->manufacturer){
2769                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2770                     hci_stack->num_cmd_packets = 1;
2771                     break;
2772                 default:
2773                     break;
2774             }
2775             break;
2776         default:
2777             break;
2778     }
2779 
2780     handle_event_for_current_stack_state(packet, size);
2781 
2782     // notify upper stack
2783 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2784 
2785     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2786     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2787         if (!packet[2]){
2788             handle = little_endian_read_16(packet, 3);
2789             hci_connection_t * aConn = hci_connection_for_handle(handle);
2790             if (aConn) {
2791                 // discard connection if app did not trigger a reconnect in the event handler
2792                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2793                     hci_shutdown_connection(aConn);
2794                 }
2795             }
2796         }
2797     }
2798 
2799 	// execute main loop
2800 	hci_run();
2801 }
2802 
2803 #ifdef ENABLE_CLASSIC
2804 
2805 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2806 static void sco_schedule_tx(hci_connection_t * conn);
2807 
2808 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2809     log_debug("SCO TX Timeout");
2810     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2811     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2812     if (!conn) return;
2813 
2814     // trigger send
2815     conn->sco_tx_ready = 1;
2816     // extra packet if CVSD but SCO buffer is too short
2817     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2818         conn->sco_tx_ready++;
2819     }
2820     hci_notify_if_sco_can_send_now();
2821 }
2822 
2823 
2824 #define SCO_TX_AFTER_RX_MS (6)
2825 
2826 static void sco_schedule_tx(hci_connection_t * conn){
2827 
2828     uint32_t now = btstack_run_loop_get_time_ms();
2829     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2830     int time_delta_ms = sco_tx_ms - now;
2831 
2832     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2833 
2834     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2835     btstack_run_loop_set_timer(timer, time_delta_ms);
2836     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2837     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2838     btstack_run_loop_add_timer(timer);
2839 }
2840 
2841 static void sco_handler(uint8_t * packet, uint16_t size){
2842     // lookup connection struct
2843     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2844     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2845     if (!conn) return;
2846 
2847     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2848     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2849         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2850             packet[2] = 0x3c;
2851             memmove(&packet[3], &packet[23], 63);
2852             size = 63;
2853         }
2854     }
2855 
2856     if (hci_have_usb_transport()){
2857         // Nothing to do
2858     } else {
2859         // 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);
2860         if (hci_stack->synchronous_flow_control_enabled == 0){
2861             uint32_t now = btstack_run_loop_get_time_ms();
2862 
2863             if (!conn->sco_rx_valid){
2864                 // ignore first 10 packets
2865                 conn->sco_rx_count++;
2866                 // log_debug("sco rx count %u", conn->sco_rx_count);
2867                 if (conn->sco_rx_count == 10) {
2868                     // use first timestamp as is and pretent it just started
2869                     conn->sco_rx_ms = now;
2870                     conn->sco_rx_valid = 1;
2871                     conn->sco_rx_count = 0;
2872                     sco_schedule_tx(conn);
2873                 }
2874             } else {
2875                 // track expected arrival timme
2876                 conn->sco_rx_count++;
2877                 conn->sco_rx_ms += 7;
2878                 int delta = (int32_t) (now - conn->sco_rx_ms);
2879                 if (delta > 0){
2880                     conn->sco_rx_ms++;
2881                 }
2882                 // log_debug("sco rx %u", conn->sco_rx_ms);
2883                 sco_schedule_tx(conn);
2884             }
2885         }
2886     }
2887     // deliver to app
2888     if (hci_stack->sco_packet_handler) {
2889         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2890     }
2891 
2892 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2893     conn->num_packets_completed++;
2894     hci_stack->host_completed_packets = 1;
2895     hci_run();
2896 #endif
2897 }
2898 #endif
2899 
2900 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2901     hci_dump_packet(packet_type, 1, packet, size);
2902     switch (packet_type) {
2903         case HCI_EVENT_PACKET:
2904             event_handler(packet, size);
2905             break;
2906         case HCI_ACL_DATA_PACKET:
2907             acl_handler(packet, size);
2908             break;
2909 #ifdef ENABLE_CLASSIC
2910         case HCI_SCO_DATA_PACKET:
2911             sco_handler(packet, size);
2912             break;
2913 #endif
2914         default:
2915             break;
2916     }
2917 }
2918 
2919 /**
2920  * @brief Add event packet handler.
2921  */
2922 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2923     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2924 }
2925 
2926 
2927 /** Register HCI packet handlers */
2928 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2929     hci_stack->acl_packet_handler = handler;
2930 }
2931 
2932 #ifdef ENABLE_CLASSIC
2933 /**
2934  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2935  */
2936 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2937     hci_stack->sco_packet_handler = handler;
2938 }
2939 #endif
2940 
2941 static void hci_state_reset(void){
2942     // no connections yet
2943     hci_stack->connections = NULL;
2944 
2945     // keep discoverable/connectable as this has been requested by the client(s)
2946     // hci_stack->discoverable = 0;
2947     // hci_stack->connectable = 0;
2948     // hci_stack->bondable = 1;
2949     // hci_stack->own_addr_type = 0;
2950 
2951     // buffer is free
2952     hci_stack->hci_packet_buffer_reserved = 0;
2953 
2954     // no pending cmds
2955     hci_stack->decline_reason = 0;
2956     hci_stack->new_scan_enable_value = 0xff;
2957 
2958     // LE
2959 #ifdef ENABLE_BLE
2960     memset(hci_stack->le_random_address, 0, 6);
2961     hci_stack->le_random_address_set = 0;
2962 #endif
2963 #ifdef ENABLE_LE_CENTRAL
2964     hci_stack->le_scanning_active  = 0;
2965     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2966     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
2967     hci_stack->le_whitelist_capacity = 0;
2968 #endif
2969 }
2970 
2971 #ifdef ENABLE_CLASSIC
2972 /**
2973  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2974  */
2975 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2976     // store and open remote device db
2977     hci_stack->link_key_db = link_key_db;
2978     if (hci_stack->link_key_db) {
2979         hci_stack->link_key_db->open();
2980     }
2981 }
2982 #endif
2983 
2984 void hci_init(const hci_transport_t *transport, const void *config){
2985 
2986 #ifdef HAVE_MALLOC
2987     if (!hci_stack) {
2988         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2989     }
2990 #else
2991     hci_stack = &hci_stack_static;
2992 #endif
2993     memset(hci_stack, 0, sizeof(hci_stack_t));
2994 
2995     // reference to use transport layer implementation
2996     hci_stack->hci_transport = transport;
2997 
2998     // reference to used config
2999     hci_stack->config = config;
3000 
3001     // setup pointer for outgoing packet buffer
3002     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
3003 
3004     // max acl payload size defined in config.h
3005     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
3006 
3007     // register packet handlers with transport
3008     transport->register_packet_handler(&packet_handler);
3009 
3010     hci_stack->state = HCI_STATE_OFF;
3011 
3012     // class of device
3013     hci_stack->class_of_device = 0x007a020c; // Smartphone
3014 
3015     // bondable by default
3016     hci_stack->bondable = 1;
3017 
3018 #ifdef ENABLE_CLASSIC
3019     // classic name
3020     hci_stack->local_name = default_classic_name;
3021 
3022     // Master slave policy
3023     hci_stack->master_slave_policy = 1;
3024 
3025     // Allow Role Switch
3026     hci_stack->allow_role_switch = 1;
3027 
3028     // Default / minimum security level = 2
3029     hci_stack->gap_security_level = LEVEL_2;
3030 
3031     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3032     hci_stack->gap_required_encyrption_key_size = 7;
3033 #endif
3034 
3035     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3036     hci_stack->ssp_enable = 1;
3037     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3038     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3039     hci_stack->ssp_auto_accept = 1;
3040 
3041     // Secure Connections: enable (requires support from Controller)
3042     hci_stack->secure_connections_enable = true;
3043 
3044     // voice setting - signed 16 bit pcm data with CVSD over the air
3045     hci_stack->sco_voice_setting = 0x60;
3046 
3047 #ifdef ENABLE_LE_CENTRAL
3048     // connection parameter to use for outgoing connections
3049     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3050     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3051     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3052     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3053     hci_stack->le_connection_latency      = 4;         // 4
3054     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3055     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3056     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3057 
3058     // default LE Scanning
3059     hci_stack->le_scan_type     =   0x1; // active
3060     hci_stack->le_scan_interval = 0x1e0; // 300 ms
3061     hci_stack->le_scan_window   =  0x30; //  30 ms
3062 #endif
3063 
3064 #ifdef ENABLE_LE_PERIPHERAL
3065     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3066 #endif
3067 
3068     // connection parameter range used to answer connection parameter update requests in l2cap
3069     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3070     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3071     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3072     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3073     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3074     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3075 
3076     hci_state_reset();
3077 }
3078 
3079 /**
3080  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3081  */
3082 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3083     hci_stack->chipset = chipset_driver;
3084 
3085     // reset chipset driver - init is also called on power_up
3086     if (hci_stack->chipset && hci_stack->chipset->init){
3087         hci_stack->chipset->init(hci_stack->config);
3088     }
3089 }
3090 
3091 /**
3092  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3093  */
3094 void hci_set_control(const btstack_control_t *hardware_control){
3095     // references to used control implementation
3096     hci_stack->control = hardware_control;
3097     // init with transport config
3098     hardware_control->init(hci_stack->config);
3099 }
3100 
3101 void hci_close(void){
3102     // close remote device db
3103     if (hci_stack->link_key_db) {
3104         hci_stack->link_key_db->close();
3105     }
3106 
3107     btstack_linked_list_iterator_t lit;
3108     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3109     while (btstack_linked_list_iterator_has_next(&lit)){
3110         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3111         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3112         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3113         hci_shutdown_connection(connection);
3114     }
3115 
3116     hci_power_control(HCI_POWER_OFF);
3117 
3118 #ifdef HAVE_MALLOC
3119     free(hci_stack);
3120 #endif
3121     hci_stack = NULL;
3122 }
3123 
3124 #ifdef ENABLE_CLASSIC
3125 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3126     // validate ranage and set
3127     if (encryption_key_size < 7)  return;
3128     if (encryption_key_size > 16) return;
3129     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3130 }
3131 
3132 void gap_set_security_level(gap_security_level_t security_level){
3133     hci_stack->gap_security_level = security_level;
3134 }
3135 
3136 gap_security_level_t gap_get_security_level(void){
3137     return hci_stack->gap_security_level;
3138 }
3139 #endif
3140 
3141 #ifdef ENABLE_CLASSIC
3142 void gap_set_class_of_device(uint32_t class_of_device){
3143     hci_stack->class_of_device = class_of_device;
3144 }
3145 
3146 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3147     hci_stack->default_link_policy_settings = default_link_policy_settings;
3148 }
3149 
3150 void gap_set_allow_role_switch(bool allow_role_switch){
3151     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3152 }
3153 
3154 uint8_t hci_get_allow_role_switch(void){
3155     return  hci_stack->allow_role_switch;
3156 }
3157 
3158 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3159     hci_stack->link_supervision_timeout = link_supervision_timeout;
3160 }
3161 
3162 void hci_disable_l2cap_timeout_check(void){
3163     disable_l2cap_timeouts = 1;
3164 }
3165 #endif
3166 
3167 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3168 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3169 void hci_set_bd_addr(bd_addr_t addr){
3170     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3171     hci_stack->custom_bd_addr_set = 1;
3172 }
3173 #endif
3174 
3175 // State-Module-Driver overview
3176 // state                    module  low-level
3177 // HCI_STATE_OFF             off      close
3178 // HCI_STATE_INITIALIZING,   on       open
3179 // HCI_STATE_WORKING,        on       open
3180 // HCI_STATE_HALTING,        on       open
3181 // HCI_STATE_SLEEPING,    off/sleep   close
3182 // HCI_STATE_FALLING_ASLEEP  on       open
3183 
3184 static int hci_power_control_on(void){
3185 
3186     // power on
3187     int err = 0;
3188     if (hci_stack->control && hci_stack->control->on){
3189         err = (*hci_stack->control->on)();
3190     }
3191     if (err){
3192         log_error( "POWER_ON failed");
3193         hci_emit_hci_open_failed();
3194         return err;
3195     }
3196 
3197     // int chipset driver
3198     if (hci_stack->chipset && hci_stack->chipset->init){
3199         hci_stack->chipset->init(hci_stack->config);
3200     }
3201 
3202     // init transport
3203     if (hci_stack->hci_transport->init){
3204         hci_stack->hci_transport->init(hci_stack->config);
3205     }
3206 
3207     // open transport
3208     err = hci_stack->hci_transport->open();
3209     if (err){
3210         log_error( "HCI_INIT failed, turning Bluetooth off again");
3211         if (hci_stack->control && hci_stack->control->off){
3212             (*hci_stack->control->off)();
3213         }
3214         hci_emit_hci_open_failed();
3215         return err;
3216     }
3217     return 0;
3218 }
3219 
3220 static void hci_power_control_off(void){
3221 
3222     log_info("hci_power_control_off");
3223 
3224     // close low-level device
3225     hci_stack->hci_transport->close();
3226 
3227     log_info("hci_power_control_off - hci_transport closed");
3228 
3229     // power off
3230     if (hci_stack->control && hci_stack->control->off){
3231         (*hci_stack->control->off)();
3232     }
3233 
3234     log_info("hci_power_control_off - control closed");
3235 
3236     hci_stack->state = HCI_STATE_OFF;
3237 }
3238 
3239 static void hci_power_control_sleep(void){
3240 
3241     log_info("hci_power_control_sleep");
3242 
3243 #if 0
3244     // don't close serial port during sleep
3245 
3246     // close low-level device
3247     hci_stack->hci_transport->close(hci_stack->config);
3248 #endif
3249 
3250     // sleep mode
3251     if (hci_stack->control && hci_stack->control->sleep){
3252         (*hci_stack->control->sleep)();
3253     }
3254 
3255     hci_stack->state = HCI_STATE_SLEEPING;
3256 }
3257 
3258 static int hci_power_control_wake(void){
3259 
3260     log_info("hci_power_control_wake");
3261 
3262     // wake on
3263     if (hci_stack->control && hci_stack->control->wake){
3264         (*hci_stack->control->wake)();
3265     }
3266 
3267 #if 0
3268     // open low-level device
3269     int err = hci_stack->hci_transport->open(hci_stack->config);
3270     if (err){
3271         log_error( "HCI_INIT failed, turning Bluetooth off again");
3272         if (hci_stack->control && hci_stack->control->off){
3273             (*hci_stack->control->off)();
3274         }
3275         hci_emit_hci_open_failed();
3276         return err;
3277     }
3278 #endif
3279 
3280     return 0;
3281 }
3282 
3283 static void hci_power_transition_to_initializing(void){
3284     // set up state machine
3285     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3286     hci_stack->hci_packet_buffer_reserved = 0;
3287     hci_stack->state = HCI_STATE_INITIALIZING;
3288     hci_stack->substate = HCI_INIT_SEND_RESET;
3289 }
3290 
3291 int hci_power_control(HCI_POWER_MODE power_mode){
3292 
3293     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3294 
3295     int err = 0;
3296     switch (hci_stack->state){
3297 
3298         case HCI_STATE_OFF:
3299             switch (power_mode){
3300                 case HCI_POWER_ON:
3301                     err = hci_power_control_on();
3302                     if (err) {
3303                         log_error("hci_power_control_on() error %d", err);
3304                         return err;
3305                     }
3306                     hci_power_transition_to_initializing();
3307                     break;
3308                 case HCI_POWER_OFF:
3309                     // do nothing
3310                     break;
3311                 case HCI_POWER_SLEEP:
3312                     // do nothing (with SLEEP == OFF)
3313                     break;
3314             }
3315             break;
3316 
3317         case HCI_STATE_INITIALIZING:
3318             switch (power_mode){
3319                 case HCI_POWER_ON:
3320                     // do nothing
3321                     break;
3322                 case HCI_POWER_OFF:
3323                     // no connections yet, just turn it off
3324                     hci_power_control_off();
3325                     break;
3326                 case HCI_POWER_SLEEP:
3327                     // no connections yet, just turn it off
3328                     hci_power_control_sleep();
3329                     break;
3330             }
3331             break;
3332 
3333         case HCI_STATE_WORKING:
3334             switch (power_mode){
3335                 case HCI_POWER_ON:
3336                     // do nothing
3337                     break;
3338                 case HCI_POWER_OFF:
3339                     // see hci_run
3340                     hci_stack->state = HCI_STATE_HALTING;
3341                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3342                     break;
3343                 case HCI_POWER_SLEEP:
3344                     // see hci_run
3345                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3346                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3347                     break;
3348             }
3349             break;
3350 
3351         case HCI_STATE_HALTING:
3352             switch (power_mode){
3353                 case HCI_POWER_ON:
3354                     hci_power_transition_to_initializing();
3355                     break;
3356                 case HCI_POWER_OFF:
3357                     // do nothing
3358                     break;
3359                 case HCI_POWER_SLEEP:
3360                     // see hci_run
3361                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3362                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3363                     break;
3364             }
3365             break;
3366 
3367         case HCI_STATE_FALLING_ASLEEP:
3368             switch (power_mode){
3369                 case HCI_POWER_ON:
3370 
3371 #ifdef HAVE_PLATFORM_IPHONE_OS
3372                     // nothing to do, if H4 supports power management
3373                     if (btstack_control_iphone_power_management_enabled()){
3374                         hci_stack->state = HCI_STATE_INITIALIZING;
3375                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3376                         break;
3377                     }
3378 #endif
3379                     hci_power_transition_to_initializing();
3380                     break;
3381                 case HCI_POWER_OFF:
3382                     // see hci_run
3383                     hci_stack->state = HCI_STATE_HALTING;
3384                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3385                     break;
3386                 case HCI_POWER_SLEEP:
3387                     // do nothing
3388                     break;
3389             }
3390             break;
3391 
3392         case HCI_STATE_SLEEPING:
3393             switch (power_mode){
3394                 case HCI_POWER_ON:
3395 
3396 #ifdef HAVE_PLATFORM_IPHONE_OS
3397                     // nothing to do, if H4 supports power management
3398                     if (btstack_control_iphone_power_management_enabled()){
3399                         hci_stack->state = HCI_STATE_INITIALIZING;
3400                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3401                         hci_update_scan_enable();
3402                         break;
3403                     }
3404 #endif
3405                     err = hci_power_control_wake();
3406                     if (err) return err;
3407                     hci_power_transition_to_initializing();
3408                     break;
3409                 case HCI_POWER_OFF:
3410                     hci_stack->state = HCI_STATE_HALTING;
3411                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3412                     break;
3413                 case HCI_POWER_SLEEP:
3414                     // do nothing
3415                     break;
3416             }
3417             break;
3418     }
3419 
3420     // create internal event
3421 	hci_emit_state();
3422 
3423 	// trigger next/first action
3424 	hci_run();
3425 
3426     return 0;
3427 }
3428 
3429 
3430 #ifdef ENABLE_CLASSIC
3431 
3432 static void hci_update_scan_enable(void){
3433     // 2 = page scan, 1 = inq scan
3434     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3435     hci_run();
3436 }
3437 
3438 void gap_discoverable_control(uint8_t enable){
3439     if (enable) enable = 1; // normalize argument
3440 
3441     if (hci_stack->discoverable == enable){
3442         hci_emit_discoverable_enabled(hci_stack->discoverable);
3443         return;
3444     }
3445 
3446     hci_stack->discoverable = enable;
3447     hci_update_scan_enable();
3448 }
3449 
3450 void gap_connectable_control(uint8_t enable){
3451     if (enable) enable = 1; // normalize argument
3452 
3453     // don't emit event
3454     if (hci_stack->connectable == enable) return;
3455 
3456     hci_stack->connectable = enable;
3457     hci_update_scan_enable();
3458 }
3459 #endif
3460 
3461 void gap_local_bd_addr(bd_addr_t address_buffer){
3462     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3463 }
3464 
3465 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3466 static void hci_host_num_completed_packets(void){
3467 
3468     // create packet manually as arrays are not supported and num_commands should not get reduced
3469     hci_reserve_packet_buffer();
3470     uint8_t * packet = hci_get_outgoing_packet_buffer();
3471 
3472     uint16_t size = 0;
3473     uint16_t num_handles = 0;
3474     packet[size++] = 0x35;
3475     packet[size++] = 0x0c;
3476     size++;  // skip param len
3477     size++;  // skip num handles
3478 
3479     // add { handle, packets } entries
3480     btstack_linked_item_t * it;
3481     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3482         hci_connection_t * connection = (hci_connection_t *) it;
3483         if (connection->num_packets_completed){
3484             little_endian_store_16(packet, size, connection->con_handle);
3485             size += 2;
3486             little_endian_store_16(packet, size, connection->num_packets_completed);
3487             size += 2;
3488             //
3489             num_handles++;
3490             connection->num_packets_completed = 0;
3491         }
3492     }
3493 
3494     packet[2] = size - 3;
3495     packet[3] = num_handles;
3496 
3497     hci_stack->host_completed_packets = 0;
3498 
3499     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3500     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3501 
3502     // release packet buffer for synchronous transport implementations
3503     if (hci_transport_synchronous()){
3504         hci_release_packet_buffer();
3505         hci_emit_transport_packet_sent();
3506     }
3507 }
3508 #endif
3509 
3510 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3511     UNUSED(ds);
3512     hci_stack->substate = HCI_HALTING_CLOSE;
3513     // allow packet handlers to defer final shutdown
3514     hci_emit_state();
3515     hci_run();
3516 }
3517 
3518 static bool hci_run_acl_fragments(void){
3519     if (hci_stack->acl_fragmentation_total_size > 0u) {
3520         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3521         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3522         if (connection) {
3523             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3524                 hci_send_acl_packet_fragments(connection);
3525                 return true;
3526             }
3527         } else {
3528             // connection gone -> discard further fragments
3529             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3530             hci_stack->acl_fragmentation_total_size = 0;
3531             hci_stack->acl_fragmentation_pos = 0;
3532         }
3533     }
3534     return false;
3535 }
3536 
3537 #ifdef ENABLE_CLASSIC
3538 static bool hci_run_general_gap_classic(void){
3539 
3540     // decline incoming connections
3541     if (hci_stack->decline_reason){
3542         uint8_t reason = hci_stack->decline_reason;
3543         hci_stack->decline_reason = 0;
3544         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3545         return true;
3546     }
3547     // send scan enable
3548     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3549         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3550         hci_stack->new_scan_enable_value = 0xff;
3551         return true;
3552     }
3553     // start/stop inquiry
3554     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3555         uint8_t duration = hci_stack->inquiry_state;
3556         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3557         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3558         return true;
3559     }
3560     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3561         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3562         hci_send_cmd(&hci_inquiry_cancel);
3563         return true;
3564     }
3565     // remote name request
3566     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3567         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3568         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3569                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3570         return true;
3571     }
3572     // pairing
3573     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3574         uint8_t state = hci_stack->gap_pairing_state;
3575         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3576         switch (state){
3577             case GAP_PAIRING_STATE_SEND_PIN:
3578                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_pin_len, hci_stack->gap_pairing_input.gap_pairing_pin);
3579                 break;
3580             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3581                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3582                 break;
3583             case GAP_PAIRING_STATE_SEND_PASSKEY:
3584                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3585                 break;
3586             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3587                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3588                 break;
3589             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3590                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3591                 break;
3592             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3593                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3594                 break;
3595             default:
3596                 break;
3597         }
3598         return true;
3599     }
3600     return false;
3601 }
3602 #endif
3603 
3604 #ifdef ENABLE_BLE
3605 static bool hci_run_general_gap_le(void){
3606 
3607     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3608 
3609     if (hci_stack->state != HCI_STATE_WORKING) return false;
3610     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0u) ) return false;
3611 
3612     // check if whitelist needs modification
3613     bool whitelist_modification_pending = false;
3614     btstack_linked_list_iterator_t lit;
3615     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3616     while (btstack_linked_list_iterator_has_next(&lit)){
3617         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3618         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3619             whitelist_modification_pending = true;
3620             break;
3621         }
3622     }
3623 
3624 #ifdef ENABLE_LE_CENTRAL
3625     // scanning control
3626     bool scanning_stop = false;
3627     if (hci_stack->le_scanning_active) {
3628         // stop if:
3629         // - parameter change required
3630         // - it's disabled
3631         // - whitelist change required but used for scanning
3632         bool scanning_uses_whitelist = (hci_stack->le_scan_filter_policy & 1) == 1;
3633         if ((hci_stack->le_scanning_param_update) || !hci_stack->le_scanning_enabled || scanning_uses_whitelist){
3634             scanning_stop = false;
3635         }
3636     }
3637 
3638     if (scanning_stop){
3639         hci_stack->le_scanning_active = 0;
3640         hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3641         return true;
3642     }
3643 
3644     if (hci_stack->le_scanning_param_update){
3645         hci_stack->le_scanning_param_update = false;
3646         hci_send_cmd(&hci_le_set_scan_parameters, hci_stack->le_scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window,
3647                      hci_stack->le_own_addr_type, hci_stack->le_scan_filter_policy);
3648         return true;
3649     }
3650 #endif
3651 
3652 #ifdef ENABLE_LE_CENTRAL
3653     // connecting control
3654     bool connecting_stop = false;
3655     if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3656         // stop connecting if:
3657         // - connecting uses white and whitelist modification pending
3658         // - if it got disabled
3659         bool connecting_uses_whitelist = hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST;
3660         if ((connecting_uses_whitelist && whitelist_modification_pending) || (hci_stack->le_connecting_request == LE_CONNECTING_IDLE)) {
3661             connecting_stop = true;
3662         }
3663     }
3664 
3665     if (connecting_stop){
3666         hci_send_cmd(&hci_le_create_connection_cancel);
3667         return true;
3668     }
3669 #endif
3670 
3671 #ifdef ENABLE_LE_PERIPHERAL
3672     // le advertisement control
3673     bool advertising_stop = false;
3674     if (hci_stack->le_advertisements_active){
3675         // stop if:
3676         // - parameter change required
3677         // - it's disabled
3678         // - whitelist change required but used for scanning
3679         bool advertising_uses_whitelist = hci_stack->le_advertisements_filter_policy > 0;
3680         if ((hci_stack->le_advertisements_todo != 0) || !hci_stack->le_advertisements_enabled_for_current_roles || advertising_uses_whitelist) {
3681             advertising_stop = true;
3682         }
3683     }
3684 
3685     if (advertising_stop){
3686         hci_stack->le_advertisements_active = 0;
3687         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3688         return true;
3689     }
3690 
3691     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3692         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3693         hci_send_cmd(&hci_le_set_advertising_parameters,
3694                      hci_stack->le_advertisements_interval_min,
3695                      hci_stack->le_advertisements_interval_max,
3696                      hci_stack->le_advertisements_type,
3697                      hci_stack->le_own_addr_type,
3698                      hci_stack->le_advertisements_direct_address_type,
3699                      hci_stack->le_advertisements_direct_address,
3700                      hci_stack->le_advertisements_channel_map,
3701                      hci_stack->le_advertisements_filter_policy);
3702         return true;
3703     }
3704     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3705         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3706         uint8_t adv_data_clean[31];
3707         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3708         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3709                      hci_stack->le_advertisements_data_len);
3710         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3711         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3712         return true;
3713     }
3714     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3715         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3716         uint8_t scan_data_clean[31];
3717         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3718         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3719                      hci_stack->le_scan_response_data_len);
3720         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3721         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3722         return true;
3723     }
3724 #endif
3725 
3726     //
3727     // LE Whitelist Management
3728     //
3729 
3730     if (whitelist_modification_pending){
3731 
3732         // add/remove entries
3733         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3734         while (btstack_linked_list_iterator_has_next(&lit)){
3735             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3736             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3737                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3738                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3739                 return true;
3740             }
3741             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3742                 bd_addr_t address;
3743                 bd_addr_type_t address_type = entry->address_type;
3744                 (void)memcpy(address, entry->address, 6);
3745                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3746                 btstack_memory_whitelist_entry_free(entry);
3747                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3748                 return true;
3749             }
3750         }
3751     }
3752 
3753 #ifdef ENABLE_LE_PERIPHERAL
3754     // re-start advertising
3755     if (hci_stack->le_advertisements_enabled_for_current_roles && (hci_stack->le_advertisements_active == 0)){
3756         // check if advertisements should be enabled given
3757         hci_stack->le_advertisements_active = 1;
3758         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3759         return true;
3760     }
3761 #endif
3762 
3763 #ifdef ENABLE_LE_CENTRAL
3764     // re-start scanning
3765     if ((hci_stack->le_scanning_enabled && !hci_stack->le_scanning_active)){
3766         hci_stack->le_scanning_active = true;
3767         hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
3768         return true;
3769     }
3770 #endif
3771 
3772 #ifdef ENABLE_LE_CENTRAL
3773     // re-start connecting
3774     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) && (hci_stack->le_connecting_request == LE_CONNECTING_WHITELIST)){
3775         bd_addr_t null_addr;
3776         memset(null_addr, 0, 6);
3777         hci_send_cmd(&hci_le_create_connection,
3778                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3779                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3780                      1,         // use whitelist
3781                      0,         // peer address type
3782                      null_addr, // peer bd addr
3783                      hci_stack->le_own_addr_type, // our addr type:
3784                      hci_stack->le_connection_interval_min,    // conn interval min
3785                      hci_stack->le_connection_interval_max,    // conn interval max
3786                      hci_stack->le_connection_latency,         // conn latency
3787                      hci_stack->le_supervision_timeout,        // conn latency
3788                      hci_stack->le_minimum_ce_length,          // min ce length
3789                      hci_stack->le_maximum_ce_length           // max ce length
3790         );
3791         return true;
3792     }
3793 #endif
3794     return false;
3795 }
3796 #endif
3797 
3798 static bool hci_run_general_pending_commands(void){
3799     btstack_linked_item_t * it;
3800     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3801         hci_connection_t * connection = (hci_connection_t *) it;
3802 
3803         switch(connection->state){
3804             case SEND_CREATE_CONNECTION:
3805                 switch(connection->address_type){
3806 #ifdef ENABLE_CLASSIC
3807                     case BD_ADDR_TYPE_ACL:
3808                         log_info("sending hci_create_connection");
3809                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3810                         break;
3811 #endif
3812                     default:
3813 #ifdef ENABLE_BLE
3814 #ifdef ENABLE_LE_CENTRAL
3815                         log_info("sending hci_le_create_connection");
3816                         hci_send_cmd(&hci_le_create_connection,
3817                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3818                                      hci_stack->le_connection_scan_window,      // conn scan windows
3819                                      0,         // don't use whitelist
3820                                      connection->address_type, // peer address type
3821                                      connection->address,      // peer bd addr
3822                                      hci_stack->le_own_addr_type, // our addr type:
3823                                      hci_stack->le_connection_interval_min,    // conn interval min
3824                                      hci_stack->le_connection_interval_max,    // conn interval max
3825                                      hci_stack->le_connection_latency,         // conn latency
3826                                      hci_stack->le_supervision_timeout,        // conn latency
3827                                      hci_stack->le_minimum_ce_length,          // min ce length
3828                                      hci_stack->le_maximum_ce_length          // max ce length
3829                         );
3830                         connection->state = SENT_CREATE_CONNECTION;
3831 #endif
3832 #endif
3833                         break;
3834                 }
3835                 return true;
3836 
3837 #ifdef ENABLE_CLASSIC
3838             case RECEIVED_CONNECTION_REQUEST:
3839                 connection->role  = HCI_ROLE_SLAVE;
3840                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3841                     log_info("sending hci_accept_connection_request");
3842                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3843                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3844                 }
3845                 return true;
3846 #endif
3847 
3848 #ifdef ENABLE_BLE
3849 #ifdef ENABLE_LE_CENTRAL
3850             case SEND_CANCEL_CONNECTION:
3851                 connection->state = SENT_CANCEL_CONNECTION;
3852                 hci_send_cmd(&hci_le_create_connection_cancel);
3853                 return true;
3854 #endif
3855 #endif
3856             case SEND_DISCONNECT:
3857                 connection->state = SENT_DISCONNECT;
3858                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3859                 return true;
3860 
3861             default:
3862                 break;
3863         }
3864 
3865         // no further commands if connection is about to get shut down
3866         if (connection->state == SENT_DISCONNECT) continue;
3867 
3868         if (connection->authentication_flags & READ_RSSI){
3869             connectionClearAuthenticationFlags(connection, READ_RSSI);
3870             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3871             return true;
3872         }
3873 
3874 #ifdef ENABLE_CLASSIC
3875 
3876         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3877             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3878             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3879             return true;
3880         }
3881 
3882         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3883             log_info("responding to link key request");
3884             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3885 
3886             link_key_t link_key;
3887             link_key_type_t link_key_type;
3888             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
3889 
3890             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
3891             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
3892             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
3893             if (sc_downgrade){
3894                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
3895                 connection->state = SENT_DISCONNECT;
3896                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3897                 return true;
3898             }
3899 
3900             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
3901             if (have_link_key && security_level_sufficient){
3902                 connection->link_key_type = link_key_type;
3903                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3904             } else {
3905                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3906             }
3907             return true;
3908         }
3909 
3910         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3911             log_info("denying to pin request");
3912             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3913             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3914             return true;
3915         }
3916 
3917         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3918             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3919             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3920             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3921                 // tweak authentication requirements
3922                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3923                 if (connection->bonding_flags & BONDING_DEDICATED){
3924                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3925                 }
3926                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3927                     authreq |= 1;
3928                 }
3929                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3930             } else {
3931                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3932             }
3933             return true;
3934         }
3935 
3936         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3937             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3938             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3939             return true;
3940         }
3941 
3942         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3943             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3944             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3945             return true;
3946         }
3947 
3948         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3949             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3950             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3951             return true;
3952         }
3953 
3954         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3955             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3956             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3957             return true;
3958         }
3959 
3960         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
3961             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
3962             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
3963             return true;
3964         }
3965 
3966         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3967             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3968             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3969             connection->state = SENT_DISCONNECT;
3970             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3971             return true;
3972         }
3973 
3974         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3975             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3976             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
3977             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3978             return true;
3979         }
3980 
3981         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3982             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3983             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3984             return true;
3985         }
3986         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3987             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3988             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3989             return true;
3990         }
3991 #endif
3992 
3993         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3994             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3995             if (connection->state != SENT_DISCONNECT){
3996                 connection->state = SENT_DISCONNECT;
3997                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3998                 return true;
3999             }
4000         }
4001 
4002 #ifdef ENABLE_CLASSIC
4003         uint16_t sniff_min_interval;
4004         switch (connection->sniff_min_interval){
4005             case 0:
4006                 break;
4007             case 0xffff:
4008                 connection->sniff_min_interval = 0;
4009                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
4010                 return true;
4011             default:
4012                 sniff_min_interval = connection->sniff_min_interval;
4013                 connection->sniff_min_interval = 0;
4014                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
4015                 return true;
4016         }
4017 
4018         if (connection->request_role != HCI_ROLE_INVALID){
4019             hci_role_t  role = connection->request_role;
4020             connection->request_role = HCI_ROLE_INVALID;
4021             hci_send_cmd(&hci_switch_role_command, connection->address, role);
4022             return true;
4023         }
4024 #endif
4025 
4026 #ifdef ENABLE_BLE
4027         switch (connection->le_con_parameter_update_state){
4028             // response to L2CAP CON PARAMETER UPDATE REQUEST
4029             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
4030                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4031                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
4032                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4033                              0x0000, 0xffff);
4034                 return true;
4035             case CON_PARAMETER_UPDATE_REPLY:
4036                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4037                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
4038                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
4039                              0x0000, 0xffff);
4040                 return true;
4041             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
4042                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
4043                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
4044                 return true;
4045             default:
4046                 break;
4047         }
4048         if (connection->le_phy_update_all_phys != 0xffu){
4049             uint8_t all_phys = connection->le_phy_update_all_phys;
4050             connection->le_phy_update_all_phys = 0xff;
4051             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);
4052             return true;
4053         }
4054 #endif
4055     }
4056     return false;
4057 }
4058 
4059 static void hci_run(void){
4060 
4061     bool done;
4062 
4063     // send continuation fragments first, as they block the prepared packet buffer
4064     done = hci_run_acl_fragments();
4065     if (done) return;
4066 
4067 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4068     // send host num completed packets next as they don't require num_cmd_packets > 0
4069     if (!hci_can_send_comand_packet_transport()) return;
4070     if (hci_stack->host_completed_packets){
4071         hci_host_num_completed_packets();
4072         return;
4073     }
4074 #endif
4075 
4076     if (!hci_can_send_command_packet_now()) return;
4077 
4078     // global/non-connection oriented commands
4079 
4080 
4081 #ifdef ENABLE_CLASSIC
4082     // general gap classic
4083     done = hci_run_general_gap_classic();
4084     if (done) return;
4085 #endif
4086 
4087 #ifdef ENABLE_BLE
4088     // general gap le
4089     done = hci_run_general_gap_le();
4090     if (done) return;
4091 #endif
4092 
4093     // send pending HCI commands
4094     done = hci_run_general_pending_commands();
4095     if (done) return;
4096 
4097     // stack state sub statemachines
4098     hci_connection_t * connection;
4099     switch (hci_stack->state){
4100         case HCI_STATE_INITIALIZING:
4101             hci_initializing_run();
4102             break;
4103 
4104         case HCI_STATE_HALTING:
4105 
4106             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4107             switch (hci_stack->substate){
4108                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4109                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4110 
4111 #ifdef ENABLE_BLE
4112 #ifdef ENABLE_LE_CENTRAL
4113                     // free whitelist entries
4114                     {
4115                         btstack_linked_list_iterator_t lit;
4116                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4117                         while (btstack_linked_list_iterator_has_next(&lit)){
4118                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4119                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4120                             btstack_memory_whitelist_entry_free(entry);
4121                         }
4122                     }
4123 #endif
4124 #endif
4125                     // close all open connections
4126                     connection =  (hci_connection_t *) hci_stack->connections;
4127                     if (connection){
4128                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4129                         if (!hci_can_send_command_packet_now()) return;
4130 
4131                         // check state
4132                         if (connection->state == SENT_DISCONNECT) return;
4133                         connection->state = SENT_DISCONNECT;
4134 
4135                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4136 
4137                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4138                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4139 
4140                         // ... which would be ignored anyway as we shutdown (free) the connection now
4141                         hci_shutdown_connection(connection);
4142 
4143                         // finally, send the disconnect command
4144                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4145                         return;
4146                     }
4147 
4148                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4149                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4150                         log_info("HCI_STATE_HALTING: wait 50 ms");
4151                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4152                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4153                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4154                         btstack_run_loop_add_timer(&hci_stack->timeout);
4155                         break;
4156                     }
4157 
4158                     /* fall through */
4159 
4160                 case HCI_HALTING_CLOSE:
4161                     log_info("HCI_STATE_HALTING, calling off");
4162 
4163                     // switch mode
4164                     hci_power_control_off();
4165 
4166                     log_info("HCI_STATE_HALTING, emitting state");
4167                     hci_emit_state();
4168                     log_info("HCI_STATE_HALTING, done");
4169                     break;
4170 
4171                 case HCI_HALTING_W4_TIMER:
4172                     // keep waiting
4173 
4174                     break;
4175                 default:
4176                     break;
4177             }
4178 
4179             break;
4180 
4181         case HCI_STATE_FALLING_ASLEEP:
4182             switch(hci_stack->substate) {
4183                 case HCI_FALLING_ASLEEP_DISCONNECT:
4184                     log_info("HCI_STATE_FALLING_ASLEEP");
4185                     // close all open connections
4186                     connection =  (hci_connection_t *) hci_stack->connections;
4187 
4188 #ifdef HAVE_PLATFORM_IPHONE_OS
4189                     // don't close connections, if H4 supports power management
4190                     if (btstack_control_iphone_power_management_enabled()){
4191                         connection = NULL;
4192                     }
4193 #endif
4194                     if (connection){
4195 
4196                         // send disconnect
4197                         if (!hci_can_send_command_packet_now()) return;
4198 
4199                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4200                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4201 
4202                         // send disconnected event right away - causes higher layer connections to get closed, too.
4203                         hci_shutdown_connection(connection);
4204                         return;
4205                     }
4206 
4207                     if (hci_classic_supported()){
4208                         // disable page and inquiry scan
4209                         if (!hci_can_send_command_packet_now()) return;
4210 
4211                         log_info("HCI_STATE_HALTING, disabling inq scans");
4212                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4213 
4214                         // continue in next sub state
4215                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4216                         break;
4217                     }
4218 
4219                     /* fall through */
4220 
4221                 case HCI_FALLING_ASLEEP_COMPLETE:
4222                     log_info("HCI_STATE_HALTING, calling sleep");
4223 #ifdef HAVE_PLATFORM_IPHONE_OS
4224                     // don't actually go to sleep, if H4 supports power management
4225                     if (btstack_control_iphone_power_management_enabled()){
4226                         // SLEEP MODE reached
4227                         hci_stack->state = HCI_STATE_SLEEPING;
4228                         hci_emit_state();
4229                         break;
4230                     }
4231 #endif
4232                     // switch mode
4233                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4234                     hci_emit_state();
4235                     break;
4236 
4237                 default:
4238                     break;
4239             }
4240             break;
4241 
4242         default:
4243             break;
4244     }
4245 }
4246 
4247 int hci_send_cmd_packet(uint8_t *packet, int size){
4248     // house-keeping
4249 
4250 #ifdef ENABLE_CLASSIC
4251     bd_addr_t addr;
4252     hci_connection_t * conn;
4253 #endif
4254 #ifdef ENABLE_LE_CENTRAL
4255     uint8_t initiator_filter_policy;
4256 #endif
4257 
4258     uint16_t opcode = little_endian_read_16(packet, 0);
4259     switch (opcode) {
4260         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4261             hci_stack->loopback_mode = packet[3];
4262             break;
4263 
4264 #ifdef ENABLE_CLASSIC
4265         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4266             reverse_bd_addr(&packet[3], addr);
4267             log_info("Create_connection to %s", bd_addr_to_str(addr));
4268 
4269             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4270             if (!conn) {
4271                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4272                 if (!conn) {
4273                     // notify client that alloc failed
4274                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4275                     return -1; // packet not sent to controller
4276                 }
4277                 conn->state = SEND_CREATE_CONNECTION;
4278                 conn->role  = HCI_ROLE_MASTER;
4279             }
4280             log_info("conn state %u", conn->state);
4281             switch (conn->state) {
4282                 // if connection active exists
4283                 case OPEN:
4284                     // and OPEN, emit connection complete command
4285                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4286                     return -1; // packet not sent to controller
4287                 case RECEIVED_DISCONNECTION_COMPLETE:
4288                     // create connection triggered in disconnect complete event, let's do it now
4289                     break;
4290                 case SEND_CREATE_CONNECTION:
4291                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4292                     break;
4293                 default:
4294                     // otherwise, just ignore as it is already in the open process
4295                     return -1; // packet not sent to controller
4296             }
4297             conn->state = SENT_CREATE_CONNECTION;
4298 
4299             // track outgoing connection
4300             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4301             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4302             break;
4303         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4304             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4305             break;
4306         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4307             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4308             break;
4309         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4310             if (hci_stack->link_key_db) {
4311                 reverse_bd_addr(&packet[3], addr);
4312                 hci_stack->link_key_db->delete_link_key(addr);
4313             }
4314             break;
4315         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4316         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4317             reverse_bd_addr(&packet[3], addr);
4318             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4319             if (conn) {
4320                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4321             }
4322             break;
4323         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4324         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4325         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4326         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4327             reverse_bd_addr(&packet[3], addr);
4328             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4329             if (conn) {
4330                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4331             }
4332             break;
4333 
4334 #ifdef ENABLE_SCO_OVER_HCI
4335         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4336             // setup_synchronous_connection? Voice setting at offset 22
4337             // TODO: compare to current setting if sco connection already active
4338             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4339             break;
4340         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4341             // accept_synchronus_connection? Voice setting at offset 18
4342             // TODO: compare to current setting if sco connection already active
4343             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4344             break;
4345 #endif
4346 #endif
4347 
4348 #ifdef ENABLE_BLE
4349         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4350             hci_stack->le_random_address_set = 1;
4351             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4352             break;
4353 #ifdef ENABLE_LE_PERIPHERAL
4354         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4355             hci_stack->le_advertisements_active = packet[3];
4356             break;
4357 #endif
4358 #ifdef ENABLE_LE_CENTRAL
4359         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4360             // white list used?
4361             initiator_filter_policy = packet[7];
4362             switch (initiator_filter_policy) {
4363                 case 0:
4364                     // whitelist not used
4365                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4366                     break;
4367                 case 1:
4368                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4369                     break;
4370                 default:
4371                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4372                     break;
4373             }
4374             // track outgoing connection
4375             hci_stack->outgoing_addr_type = packet[8];              // peer addres type
4376             reverse_bd_addr( &packet[9], hci_stack->outgoing_addr); // peer address
4377             break;
4378         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4379             hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4380             break;
4381 #endif
4382 #endif
4383         default:
4384             break;
4385     }
4386 
4387     hci_stack->num_cmd_packets--;
4388 
4389     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4390     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4391 }
4392 
4393 // disconnect because of security block
4394 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4395     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4396     if (!connection) return;
4397     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4398 }
4399 
4400 
4401 // Configure Secure Simple Pairing
4402 
4403 #ifdef ENABLE_CLASSIC
4404 
4405 // enable will enable SSP during init
4406 void gap_ssp_set_enable(int enable){
4407     hci_stack->ssp_enable = enable;
4408 }
4409 
4410 static int hci_local_ssp_activated(void){
4411     return gap_ssp_supported() && hci_stack->ssp_enable;
4412 }
4413 
4414 // if set, BTstack will respond to io capability request using authentication requirement
4415 void gap_ssp_set_io_capability(int io_capability){
4416     hci_stack->ssp_io_capability = io_capability;
4417 }
4418 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4419     hci_stack->ssp_authentication_requirement = authentication_requirement;
4420 }
4421 
4422 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4423 void gap_ssp_set_auto_accept(int auto_accept){
4424     hci_stack->ssp_auto_accept = auto_accept;
4425 }
4426 
4427 void gap_secure_connections_enable(bool enable){
4428     hci_stack->secure_connections_enable = enable;
4429 }
4430 
4431 #endif
4432 
4433 // va_list part of hci_send_cmd
4434 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4435     if (!hci_can_send_command_packet_now()){
4436         log_error("hci_send_cmd called but cannot send packet now");
4437         return 0;
4438     }
4439 
4440     // for HCI INITIALIZATION
4441     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4442     hci_stack->last_cmd_opcode = cmd->opcode;
4443 
4444     hci_reserve_packet_buffer();
4445     uint8_t * packet = hci_stack->hci_packet_buffer;
4446     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4447     int err = hci_send_cmd_packet(packet, size);
4448 
4449     // release packet buffer on error or for synchronous transport implementations
4450     if ((err < 0) || hci_transport_synchronous()){
4451         hci_release_packet_buffer();
4452         hci_emit_transport_packet_sent();
4453     }
4454 
4455     return err;
4456 }
4457 
4458 /**
4459  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4460  */
4461 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4462     va_list argptr;
4463     va_start(argptr, cmd);
4464     int res = hci_send_cmd_va_arg(cmd, argptr);
4465     va_end(argptr);
4466     return res;
4467 }
4468 
4469 // Create various non-HCI events.
4470 // TODO: generalize, use table similar to hci_create_command
4471 
4472 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4473     // dump packet
4474     if (dump) {
4475         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4476     }
4477 
4478     // dispatch to all event handlers
4479     btstack_linked_list_iterator_t it;
4480     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4481     while (btstack_linked_list_iterator_has_next(&it)){
4482         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4483         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4484     }
4485 }
4486 
4487 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4488     if (!hci_stack->acl_packet_handler) return;
4489     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4490 }
4491 
4492 #ifdef ENABLE_CLASSIC
4493 static void hci_notify_if_sco_can_send_now(void){
4494     // notify SCO sender if waiting
4495     if (!hci_stack->sco_waiting_for_can_send_now) return;
4496     if (hci_can_send_sco_packet_now()){
4497         hci_stack->sco_waiting_for_can_send_now = 0;
4498         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4499         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4500         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4501     }
4502 }
4503 
4504 // parsing end emitting has been merged to reduce code size
4505 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4506     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4507 
4508     uint8_t * eir_data;
4509     ad_context_t context;
4510     const uint8_t * name;
4511     uint8_t         name_len;
4512 
4513     if (size < 3) return;
4514 
4515     int event_type = hci_event_packet_get_type(packet);
4516     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4517     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4518 
4519     switch (event_type){
4520         case HCI_EVENT_INQUIRY_RESULT:
4521         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4522             if (size != (3 + (num_responses * 14))) return;
4523             break;
4524         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4525             if (size != 257) return;
4526             if (num_responses != 1) return;
4527             break;
4528         default:
4529             return;
4530     }
4531 
4532     // event[1] is set at the end
4533     int i;
4534     for (i=0; i<num_responses;i++){
4535         memset(event, 0, sizeof(event));
4536         event[0] = GAP_EVENT_INQUIRY_RESULT;
4537         uint8_t event_size = 18;    // if name is not set by EIR
4538 
4539         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4540         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4541         (void)memcpy(&event[9],
4542                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4543                      3); // class of device
4544         (void)memcpy(&event[12],
4545                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4546                      2); // clock offset
4547 
4548         switch (event_type){
4549             case HCI_EVENT_INQUIRY_RESULT:
4550                 // 14,15,16,17 = 0, size 18
4551                 break;
4552             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4553                 event[14] = 1;
4554                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4555                 // 16,17 = 0, size 18
4556                 break;
4557             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4558                 event[14] = 1;
4559                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4560                 // EIR packets only contain a single inquiry response
4561                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4562                 name = NULL;
4563                 // Iterate over EIR data
4564                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4565                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4566                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4567                     const uint8_t * data = ad_iterator_get_data(&context);
4568                     // Prefer Complete Local Name over Shortend Local Name
4569                     switch (data_type){
4570                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4571                             if (name) continue;
4572                             /* fall through */
4573                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4574                             name = data;
4575                             name_len = data_size;
4576                             break;
4577                         default:
4578                             break;
4579                     }
4580                 }
4581                 if (name){
4582                     event[16] = 1;
4583                     // truncate name if needed
4584                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4585                     event[17] = len;
4586                     (void)memcpy(&event[18], name, len);
4587                     event_size += len;
4588                 }
4589                 break;
4590         }
4591         event[1] = event_size - 2;
4592         hci_emit_event(event, event_size, 1);
4593     }
4594 }
4595 #endif
4596 
4597 void hci_emit_state(void){
4598     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4599     uint8_t event[3];
4600     event[0] = BTSTACK_EVENT_STATE;
4601     event[1] = sizeof(event) - 2u;
4602     event[2] = hci_stack->state;
4603     hci_emit_event(event, sizeof(event), 1);
4604 }
4605 
4606 #ifdef ENABLE_CLASSIC
4607 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4608     uint8_t event[13];
4609     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4610     event[1] = sizeof(event) - 2;
4611     event[2] = status;
4612     little_endian_store_16(event, 3, con_handle);
4613     reverse_bd_addr(address, &event[5]);
4614     event[11] = 1; // ACL connection
4615     event[12] = 0; // encryption disabled
4616     hci_emit_event(event, sizeof(event), 1);
4617 }
4618 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4619     if (disable_l2cap_timeouts) return;
4620     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4621     uint8_t event[4];
4622     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4623     event[1] = sizeof(event) - 2;
4624     little_endian_store_16(event, 2, conn->con_handle);
4625     hci_emit_event(event, sizeof(event), 1);
4626 }
4627 #endif
4628 
4629 #ifdef ENABLE_BLE
4630 #ifdef ENABLE_LE_CENTRAL
4631 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4632     uint8_t event[21];
4633     event[0] = HCI_EVENT_LE_META;
4634     event[1] = sizeof(event) - 2u;
4635     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4636     event[3] = status;
4637     little_endian_store_16(event, 4, con_handle);
4638     event[6] = 0; // TODO: role
4639     event[7] = address_type;
4640     reverse_bd_addr(address, &event[8]);
4641     little_endian_store_16(event, 14, 0); // interval
4642     little_endian_store_16(event, 16, 0); // latency
4643     little_endian_store_16(event, 18, 0); // supervision timeout
4644     event[20] = 0; // master clock accuracy
4645     hci_emit_event(event, sizeof(event), 1);
4646 }
4647 #endif
4648 #endif
4649 
4650 static void hci_emit_transport_packet_sent(void){
4651     // notify upper stack that it might be possible to send again
4652     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4653     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4654 }
4655 
4656 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4657     uint8_t event[6];
4658     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4659     event[1] = sizeof(event) - 2u;
4660     event[2] = 0; // status = OK
4661     little_endian_store_16(event, 3, con_handle);
4662     event[5] = reason;
4663     hci_emit_event(event, sizeof(event), 1);
4664 }
4665 
4666 static void hci_emit_nr_connections_changed(void){
4667     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4668     uint8_t event[3];
4669     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4670     event[1] = sizeof(event) - 2u;
4671     event[2] = nr_hci_connections();
4672     hci_emit_event(event, sizeof(event), 1);
4673 }
4674 
4675 static void hci_emit_hci_open_failed(void){
4676     log_info("BTSTACK_EVENT_POWERON_FAILED");
4677     uint8_t event[2];
4678     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4679     event[1] = sizeof(event) - 2u;
4680     hci_emit_event(event, sizeof(event), 1);
4681 }
4682 
4683 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4684     log_info("hci_emit_dedicated_bonding_result %u ", status);
4685     uint8_t event[9];
4686     int pos = 0;
4687     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4688     event[pos++] = sizeof(event) - 2u;
4689     event[pos++] = status;
4690     reverse_bd_addr(address, &event[pos]);
4691     hci_emit_event(event, sizeof(event), 1);
4692 }
4693 
4694 
4695 #ifdef ENABLE_CLASSIC
4696 
4697 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4698     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4699     uint8_t event[5];
4700     int pos = 0;
4701     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4702     event[pos++] = sizeof(event) - 2;
4703     little_endian_store_16(event, 2, con_handle);
4704     pos += 2;
4705     event[pos++] = level;
4706     hci_emit_event(event, sizeof(event), 1);
4707 }
4708 
4709 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4710     if (!connection) return LEVEL_0;
4711     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4712     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4713     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4714     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4715     // LEVEL 4 always requires 128 bit encrytion key size
4716     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4717         security_level = LEVEL_3;
4718     }
4719     return security_level;
4720 }
4721 
4722 static void hci_emit_discoverable_enabled(uint8_t enabled){
4723     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4724     uint8_t event[3];
4725     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4726     event[1] = sizeof(event) - 2;
4727     event[2] = enabled;
4728     hci_emit_event(event, sizeof(event), 1);
4729 }
4730 
4731 // query if remote side supports eSCO
4732 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4733     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4734     if (!connection) return 0;
4735     return (connection->remote_supported_features[0] & 1) != 0;
4736 }
4737 
4738 static bool hci_ssp_supported(hci_connection_t * connection){
4739     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4740     return (connection->bonding_flags & mask) == mask;
4741 }
4742 
4743 // query if remote side supports SSP
4744 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4745     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4746     if (!connection) return 0;
4747     return hci_ssp_supported(connection) ? 1 : 0;
4748 }
4749 
4750 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4751     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4752 }
4753 
4754 // GAP API
4755 /**
4756  * @bbrief enable/disable bonding. default is enabled
4757  * @praram enabled
4758  */
4759 void gap_set_bondable_mode(int enable){
4760     hci_stack->bondable = enable ? 1 : 0;
4761 }
4762 /**
4763  * @brief Get bondable mode.
4764  * @return 1 if bondable
4765  */
4766 int gap_get_bondable_mode(void){
4767     return hci_stack->bondable;
4768 }
4769 
4770 /**
4771  * @brief map link keys to security levels
4772  */
4773 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4774     switch (link_key_type){
4775         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4776             return LEVEL_4;
4777         case COMBINATION_KEY:
4778         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4779             return LEVEL_3;
4780         default:
4781             return LEVEL_2;
4782     }
4783 }
4784 
4785 /**
4786  * @brief map link keys to secure connection yes/no
4787  */
4788 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4789     switch (link_key_type){
4790         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4791         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4792             return 1;
4793         default:
4794             return 0;
4795     }
4796 }
4797 
4798 /**
4799  * @brief map link keys to authenticated
4800  */
4801 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4802     switch (link_key_type){
4803         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4804         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4805             return 1;
4806         default:
4807             return 0;
4808     }
4809 }
4810 
4811 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4812     log_info("gap_mitm_protection_required_for_security_level %u", level);
4813     return level > LEVEL_2;
4814 }
4815 
4816 /**
4817  * @brief get current security level
4818  */
4819 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4820     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4821     if (!connection) return LEVEL_0;
4822     return gap_security_level_for_connection(connection);
4823 }
4824 
4825 /**
4826  * @brief request connection to device to
4827  * @result GAP_AUTHENTICATION_RESULT
4828  */
4829 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4830     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4831     if (!connection){
4832         hci_emit_security_level(con_handle, LEVEL_0);
4833         return;
4834     }
4835     gap_security_level_t current_level = gap_security_level(con_handle);
4836     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4837         requested_level, connection->requested_security_level, current_level);
4838 
4839     // assumption: earlier requested security higher than current level => security request is active
4840     if (current_level < connection->requested_security_level){
4841         if (connection->requested_security_level < requested_level){
4842             // increase requested level as new level is higher
4843 
4844             // TODO: handle re-authentication when done
4845 
4846             connection->requested_security_level = requested_level;
4847         }
4848         return;
4849     }
4850 
4851     // no request active, notify if security sufficient
4852     if (requested_level <= current_level){
4853         hci_emit_security_level(con_handle, current_level);
4854         return;
4855     }
4856 
4857     // start pairing to increase security level
4858     connection->requested_security_level = requested_level;
4859 
4860 #if 0
4861     // sending encryption request without a link key results in an error.
4862     // TODO: figure out how to use it properly
4863 
4864     // would enabling ecnryption suffice (>= LEVEL_2)?
4865     if (hci_stack->link_key_db){
4866         link_key_type_t link_key_type;
4867         link_key_t      link_key;
4868         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4869             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4870                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4871                 return;
4872             }
4873         }
4874     }
4875 #endif
4876 
4877     // start to authenticate connection if not already active
4878     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
4879     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4880     hci_run();
4881 }
4882 
4883 /**
4884  * @brief start dedicated bonding with device. disconnect after bonding
4885  * @param device
4886  * @param request MITM protection
4887  * @result GAP_DEDICATED_BONDING_COMPLETE
4888  */
4889 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4890 
4891     // create connection state machine
4892     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4893 
4894     if (!connection){
4895         return BTSTACK_MEMORY_ALLOC_FAILED;
4896     }
4897 
4898     // delete linkn key
4899     gap_drop_link_key_for_bd_addr(device);
4900 
4901     // configure LEVEL_2/3, dedicated bonding
4902     connection->state = SEND_CREATE_CONNECTION;
4903     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4904     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4905     connection->bonding_flags = BONDING_DEDICATED;
4906 
4907     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4908 
4909     // handle: connnection failure (connection complete != ok)
4910     // handle: authentication failure
4911     // handle: disconnect on done
4912 
4913     hci_run();
4914 
4915     return 0;
4916 }
4917 #endif
4918 
4919 void gap_set_local_name(const char * local_name){
4920     hci_stack->local_name = local_name;
4921 }
4922 
4923 
4924 #ifdef ENABLE_BLE
4925 
4926 #ifdef ENABLE_LE_CENTRAL
4927 void gap_start_scan(void){
4928     hci_stack->le_scanning_enabled = true;
4929     hci_run();
4930 }
4931 
4932 void gap_stop_scan(void){
4933     hci_stack->le_scanning_enabled = false;
4934     hci_run();
4935 }
4936 
4937 void gap_set_scan_params(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window, uint8_t scanning_filter_policy){
4938     hci_stack->le_scan_type          = scan_type;
4939     hci_stack->le_scan_filter_policy = scanning_filter_policy;
4940     hci_stack->le_scan_interval      = scan_interval;
4941     hci_stack->le_scan_window        = scan_window;
4942     hci_stack->le_scanning_param_update = true;
4943     hci_run();
4944 }
4945 
4946 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4947     gap_set_scan_params(scan_type, scan_interval, scan_window, 0);
4948 }
4949 
4950 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4951     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4952     if (!conn){
4953         // disallow if le connection is already outgoing
4954         if (hci_is_le_connection_type(addr_type) && hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
4955             log_error("le connection already active");
4956             return ERROR_CODE_COMMAND_DISALLOWED;
4957         }
4958 
4959         log_info("gap_connect: no connection exists yet, creating context");
4960         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4961         if (!conn){
4962             // notify client that alloc failed
4963             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4964             log_info("gap_connect: failed to alloc hci_connection_t");
4965             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4966         }
4967 
4968         // set le connecting state
4969         if (hci_is_le_connection_type(addr_type)){
4970             hci_stack->le_connecting_request = LE_CONNECTING_DIRECT;
4971         }
4972 
4973         conn->state = SEND_CREATE_CONNECTION;
4974         log_info("gap_connect: send create connection next");
4975         hci_run();
4976         return ERROR_CODE_SUCCESS;
4977     }
4978 
4979     if (!hci_is_le_connection(conn) ||
4980         (conn->state == SEND_CREATE_CONNECTION) ||
4981         (conn->state == SENT_CREATE_CONNECTION)) {
4982         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4983         log_error("gap_connect: classic connection or connect is already being created");
4984         return GATT_CLIENT_IN_WRONG_STATE;
4985     }
4986 
4987     // check if connection was just disconnected
4988     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4989         log_info("gap_connect: send create connection (again)");
4990         conn->state = SEND_CREATE_CONNECTION;
4991         hci_run();
4992         return ERROR_CODE_SUCCESS;
4993     }
4994 
4995     log_info("gap_connect: context exists with state %u", conn->state);
4996     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, ERROR_CODE_SUCCESS);
4997     hci_run();
4998     return ERROR_CODE_SUCCESS;
4999 }
5000 
5001 // @assumption: only a single outgoing LE Connection exists
5002 static hci_connection_t * gap_get_outgoing_connection(void){
5003     btstack_linked_item_t *it;
5004     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
5005         hci_connection_t * conn = (hci_connection_t *) it;
5006         if (!hci_is_le_connection(conn)) continue;
5007         switch (conn->state){
5008             case SEND_CREATE_CONNECTION:
5009             case SENT_CREATE_CONNECTION:
5010             case SENT_CANCEL_CONNECTION:
5011                 return conn;
5012             default:
5013                 break;
5014         };
5015     }
5016     return NULL;
5017 }
5018 
5019 uint8_t gap_connect_cancel(void){
5020     hci_connection_t * conn = gap_get_outgoing_connection();
5021     if (!conn) return 0;
5022     switch (conn->state){
5023         case SEND_CREATE_CONNECTION:
5024             // skip sending create connection and emit event instead
5025             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
5026             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
5027             btstack_memory_hci_connection_free( conn );
5028             break;
5029         case SENT_CREATE_CONNECTION:
5030             // request to send cancel connection
5031             conn->state = SEND_CANCEL_CONNECTION;
5032             hci_run();
5033             break;
5034         default:
5035             break;
5036     }
5037     return 0;
5038 }
5039 #endif
5040 
5041 #ifdef ENABLE_LE_CENTRAL
5042 /**
5043  * @brief Set connection parameters for outgoing connections
5044  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
5045  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
5046  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
5047  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
5048  * @param conn_latency, default: 4
5049  * @param supervision_timeout (unit: 10ms), default: 720 ms
5050  * @param min_ce_length (unit: 0.625ms), default: 10 ms
5051  * @param max_ce_length (unit: 0.625ms), default: 30 ms
5052  */
5053 
5054 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
5055     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
5056     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
5057     hci_stack->le_connection_scan_interval = conn_scan_interval;
5058     hci_stack->le_connection_scan_window = conn_scan_window;
5059     hci_stack->le_connection_interval_min = conn_interval_min;
5060     hci_stack->le_connection_interval_max = conn_interval_max;
5061     hci_stack->le_connection_latency = conn_latency;
5062     hci_stack->le_supervision_timeout = supervision_timeout;
5063     hci_stack->le_minimum_ce_length = min_ce_length;
5064     hci_stack->le_maximum_ce_length = max_ce_length;
5065 }
5066 #endif
5067 
5068 /**
5069  * @brief Updates the connection parameters for a given LE connection
5070  * @param handle
5071  * @param conn_interval_min (unit: 1.25ms)
5072  * @param conn_interval_max (unit: 1.25ms)
5073  * @param conn_latency
5074  * @param supervision_timeout (unit: 10ms)
5075  * @returns 0 if ok
5076  */
5077 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5078     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5079     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5080     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5081     connection->le_conn_interval_min = conn_interval_min;
5082     connection->le_conn_interval_max = conn_interval_max;
5083     connection->le_conn_latency = conn_latency;
5084     connection->le_supervision_timeout = supervision_timeout;
5085     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5086     hci_run();
5087     return 0;
5088 }
5089 
5090 /**
5091  * @brief Request an update of the connection parameter for a given LE connection
5092  * @param handle
5093  * @param conn_interval_min (unit: 1.25ms)
5094  * @param conn_interval_max (unit: 1.25ms)
5095  * @param conn_latency
5096  * @param supervision_timeout (unit: 10ms)
5097  * @returns 0 if ok
5098  */
5099 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5100     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5101     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5102     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5103     connection->le_conn_interval_min = conn_interval_min;
5104     connection->le_conn_interval_max = conn_interval_max;
5105     connection->le_conn_latency = conn_latency;
5106     connection->le_supervision_timeout = supervision_timeout;
5107     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5108     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5109     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5110     return 0;
5111 }
5112 
5113 #ifdef ENABLE_LE_PERIPHERAL
5114 
5115 /**
5116  * @brief Set Advertisement Data
5117  * @param advertising_data_length
5118  * @param advertising_data (max 31 octets)
5119  * @note data is not copied, pointer has to stay valid
5120  */
5121 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5122     hci_stack->le_advertisements_data_len = advertising_data_length;
5123     hci_stack->le_advertisements_data = advertising_data;
5124     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5125     hci_run();
5126 }
5127 
5128 /**
5129  * @brief Set Scan Response Data
5130  * @param advertising_data_length
5131  * @param advertising_data (max 31 octets)
5132  * @note data is not copied, pointer has to stay valid
5133  */
5134 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5135     hci_stack->le_scan_response_data_len = scan_response_data_length;
5136     hci_stack->le_scan_response_data = scan_response_data;
5137     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5138     hci_run();
5139 }
5140 
5141 /**
5142  * @brief Set Advertisement Parameters
5143  * @param adv_int_min
5144  * @param adv_int_max
5145  * @param adv_type
5146  * @param direct_address_type
5147  * @param direct_address
5148  * @param channel_map
5149  * @param filter_policy
5150  *
5151  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5152  */
5153  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5154     uint8_t direct_address_typ, bd_addr_t direct_address,
5155     uint8_t channel_map, uint8_t filter_policy) {
5156 
5157     hci_stack->le_advertisements_interval_min = adv_int_min;
5158     hci_stack->le_advertisements_interval_max = adv_int_max;
5159     hci_stack->le_advertisements_type = adv_type;
5160     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5161     hci_stack->le_advertisements_channel_map = channel_map;
5162     hci_stack->le_advertisements_filter_policy = filter_policy;
5163     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5164                  6);
5165 
5166     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5167     hci_run();
5168  }
5169 
5170 /**
5171  * @brief Enable/Disable Advertisements
5172  * @param enabled
5173  */
5174 void gap_advertisements_enable(int enabled){
5175     hci_stack->le_advertisements_enabled = enabled;
5176     hci_update_advertisements_enabled_for_current_roles();
5177     hci_run();
5178 }
5179 
5180 #endif
5181 
5182 void hci_le_set_own_address_type(uint8_t own_address_type){
5183     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5184     if (own_address_type == hci_stack->le_own_addr_type) return;
5185     hci_stack->le_own_addr_type = own_address_type;
5186 
5187 #ifdef ENABLE_LE_PERIPHERAL
5188     // update advertisement parameters, too
5189     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5190     hci_run();
5191 #endif
5192 #ifdef ENABLE_LE_CENTRAL
5193     // note: we don't update scan parameters or modify ongoing connection attempts
5194 #endif
5195 }
5196 
5197 #endif
5198 
5199 uint8_t gap_disconnect(hci_con_handle_t handle){
5200     hci_connection_t * conn = hci_connection_for_handle(handle);
5201     if (!conn){
5202         hci_emit_disconnection_complete(handle, 0);
5203         return 0;
5204     }
5205     // ignore if already disconnected
5206     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5207         return 0;
5208     }
5209     conn->state = SEND_DISCONNECT;
5210     hci_run();
5211     return 0;
5212 }
5213 
5214 int gap_read_rssi(hci_con_handle_t con_handle){
5215     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5216     if (hci_connection == NULL) return 0;
5217     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5218     hci_run();
5219     return 1;
5220 }
5221 
5222 /**
5223  * @brief Get connection type
5224  * @param con_handle
5225  * @result connection_type
5226  */
5227 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5228     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5229     if (!conn) return GAP_CONNECTION_INVALID;
5230     switch (conn->address_type){
5231         case BD_ADDR_TYPE_LE_PUBLIC:
5232         case BD_ADDR_TYPE_LE_RANDOM:
5233             return GAP_CONNECTION_LE;
5234         case BD_ADDR_TYPE_SCO:
5235             return GAP_CONNECTION_SCO;
5236         case BD_ADDR_TYPE_ACL:
5237             return GAP_CONNECTION_ACL;
5238         default:
5239             return GAP_CONNECTION_INVALID;
5240     }
5241 }
5242 
5243 hci_role_t gap_get_role(hci_con_handle_t connection_handle){
5244     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5245     if (!conn) return HCI_ROLE_INVALID;
5246     return (hci_role_t) conn->role;
5247 }
5248 
5249 
5250 #ifdef ENABLE_CLASSIC
5251 uint8_t gap_request_role(bd_addr_t addr, hci_role_t role){
5252     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5253     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5254     conn->request_role = role;
5255     hci_run();
5256     return ERROR_CODE_SUCCESS;
5257 }
5258 #endif
5259 
5260 #ifdef ENABLE_BLE
5261 
5262 uint8_t gap_le_set_phy(hci_con_handle_t connection_handle, uint8_t all_phys, uint8_t tx_phys, uint8_t rx_phys, uint8_t phy_options){
5263     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5264     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5265 
5266     conn->le_phy_update_all_phys    = all_phys;
5267     conn->le_phy_update_tx_phys     = tx_phys;
5268     conn->le_phy_update_rx_phys     = rx_phys;
5269     conn->le_phy_update_phy_options = phy_options;
5270 
5271     hci_run();
5272 
5273     return 0;
5274 }
5275 
5276 static uint8_t hci_whitelist_add(bd_addr_type_t address_type, bd_addr_t address){
5277     // check if already in list
5278     btstack_linked_list_iterator_t it;
5279     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5280     while (btstack_linked_list_iterator_has_next(&it)) {
5281         whitelist_entry_t *entry = (whitelist_entry_t *) btstack_linked_list_iterator_next(&it);
5282         if (entry->address_type != address_type) {
5283             continue;
5284         }
5285         if (memcmp(entry->address, address, 6) != 0) {
5286             continue;
5287         }
5288         // already in there
5289         return ERROR_CODE_COMMAND_DISALLOWED;
5290     }
5291     // alloc and add to list
5292     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5293     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5294     entry->address_type = address_type;
5295     (void)memcpy(entry->address, address, 6);
5296     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5297     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5298     return ERROR_CODE_SUCCESS;
5299 }
5300 
5301 static uint8_t hci_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address){
5302     btstack_linked_list_iterator_t it;
5303     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5304     while (btstack_linked_list_iterator_has_next(&it)){
5305         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5306         if (entry->address_type != address_type) {
5307             continue;
5308         }
5309         if (memcmp(entry->address, address, 6) != 0) {
5310             continue;
5311         }
5312         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5313             // remove from controller if already present
5314             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5315         }  else {
5316             // directly remove entry from whitelist
5317             btstack_linked_list_iterator_remove(&it);
5318             btstack_memory_whitelist_entry_free(entry);
5319         }
5320         return ERROR_CODE_SUCCESS;
5321     }
5322     return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5323 }
5324 
5325 static void hci_whitelist_clear(void){
5326     btstack_linked_list_iterator_t it;
5327     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5328     while (btstack_linked_list_iterator_has_next(&it)){
5329         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5330         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5331             // remove from controller if already present
5332             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5333             continue;
5334         }
5335         // directly remove entry from whitelist
5336         btstack_linked_list_iterator_remove(&it);
5337         btstack_memory_whitelist_entry_free(entry);
5338     }
5339 }
5340 
5341 /**
5342  * @brief Clear Whitelist
5343  * @returns 0 if ok
5344  */
5345 uint8_t gap_whitelist_clear(void){
5346     hci_whitelist_clear();
5347     hci_run();
5348     return ERROR_CODE_SUCCESS;
5349 }
5350 
5351 /**
5352  * @brief Add Device to Whitelist
5353  * @param address_typ
5354  * @param address
5355  * @returns 0 if ok
5356  */
5357 uint8_t gap_whitelist_add(bd_addr_type_t address_type, bd_addr_t address){
5358     uint8_t status = hci_whitelist_add(address_type, address);
5359     if (status){
5360         return status;
5361     }
5362     hci_run();
5363     return ERROR_CODE_SUCCESS;
5364 }
5365 
5366 /**
5367  * @brief Remove Device from Whitelist
5368  * @param address_typ
5369  * @param address
5370  * @returns 0 if ok
5371  */
5372 uint8_t gap_whitelist_remove(bd_addr_type_t address_type, bd_addr_t address){
5373     uint8_t status = hci_whitelist_remove(address_type, address);
5374     if (status){
5375         return status;
5376     }
5377     hci_run();
5378     return ERROR_CODE_SUCCESS;
5379 }
5380 
5381 #ifdef ENABLE_LE_CENTRAL
5382 /**
5383  *  @brief Connect with Whitelist
5384  *  @note Explicit whitelist management and this connect with whitelist replace deprecated gap_auto_connection_* functions
5385  *  @returns - if ok
5386  */
5387 uint8_t gap_connect_with_whitelist(void){
5388     if (hci_stack->le_connecting_request != LE_CONNECTING_IDLE){
5389         return ERROR_CODE_COMMAND_DISALLOWED;
5390     }
5391     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5392     hci_run();
5393     return ERROR_CODE_SUCCESS;
5394 }
5395 
5396 /**
5397  * @brief Auto Connection Establishment - Start Connecting to device
5398  * @param address_typ
5399  * @param address
5400  * @returns 0 if ok
5401  */
5402 uint8_t gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5403     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5404         return ERROR_CODE_COMMAND_DISALLOWED;
5405     }
5406 
5407     uint8_t status = hci_whitelist_add(address_type, address);
5408     if (status != ERROR_CODE_SUCCESS) {
5409         return status;
5410     }
5411 
5412     hci_stack->le_connecting_request = LE_CONNECTING_WHITELIST;
5413 
5414     hci_run();
5415     return ERROR_CODE_SUCCESS;
5416 }
5417 
5418 /**
5419  * @brief Auto Connection Establishment - Stop Connecting to device
5420  * @param address_typ
5421  * @param address
5422  * @returns 0 if ok
5423  */
5424 uint8_t gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5425     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT){
5426         return ERROR_CODE_COMMAND_DISALLOWED;
5427     }
5428 
5429     hci_whitelist_remove(address_type, address);
5430     if (btstack_linked_list_empty(&hci_stack->le_whitelist)){
5431         hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5432     }
5433     hci_run();
5434     return 0;
5435 }
5436 
5437 /**
5438  * @brief Auto Connection Establishment - Stop everything
5439  * @note  Convenience function to stop all active auto connection attempts
5440  */
5441 uint8_t gap_auto_connection_stop_all(void){
5442     if (hci_stack->le_connecting_request == LE_CONNECTING_DIRECT) {
5443         return ERROR_CODE_COMMAND_DISALLOWED;
5444     }
5445     hci_whitelist_clear();
5446     hci_stack->le_connecting_request = LE_CONNECTING_IDLE;
5447     hci_run();
5448     return ERROR_CODE_SUCCESS;
5449 }
5450 
5451 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5452     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5453     if (!conn) return 0;
5454     return conn->le_connection_interval;
5455 }
5456 #endif
5457 #endif
5458 
5459 #ifdef ENABLE_CLASSIC
5460 /**
5461  * @brief Set Extended Inquiry Response data
5462  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5463  * @note has to be done before stack starts up
5464  */
5465 void gap_set_extended_inquiry_response(const uint8_t * data){
5466     hci_stack->eir_data = data;
5467 }
5468 
5469 /**
5470  * @brief Start GAP Classic Inquiry
5471  * @param duration in 1.28s units
5472  * @return 0 if ok
5473  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5474  */
5475 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5476     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5477     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5478     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5479         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5480     }
5481     hci_stack->inquiry_state = duration_in_1280ms_units;
5482     hci_run();
5483     return 0;
5484 }
5485 
5486 /**
5487  * @brief Stop GAP Classic Inquiry
5488  * @returns 0 if ok
5489  */
5490 int gap_inquiry_stop(void){
5491     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5492         // emit inquiry complete event, before it even started
5493         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5494         hci_emit_event(event, sizeof(event), 1);
5495         return 0;
5496     }
5497     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5498     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5499     hci_run();
5500     return 0;
5501 }
5502 
5503 
5504 /**
5505  * @brief Remote Name Request
5506  * @param addr
5507  * @param page_scan_repetition_mode
5508  * @param clock_offset only used when bit 15 is set
5509  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5510  */
5511 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5512     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5513     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5514     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5515     hci_stack->remote_name_clock_offset = clock_offset;
5516     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5517     hci_run();
5518     return 0;
5519 }
5520 
5521 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5522     hci_stack->gap_pairing_state = state;
5523     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5524     hci_run();
5525     return 0;
5526 }
5527 
5528 /**
5529  * @brief Legacy Pairing Pin Code Response for binary data / non-strings
5530  * @param addr
5531  * @param pin_data
5532  * @param pin_len
5533  * @return 0 if ok
5534  */
5535 int gap_pin_code_response_binary(bd_addr_t addr, const uint8_t * pin_data, uint8_t pin_len){
5536     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5537     hci_stack->gap_pairing_input.gap_pairing_pin = pin_data;
5538     hci_stack->gap_pairing_pin_len = pin_len;
5539     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5540 }
5541 
5542 /**
5543  * @brief Legacy Pairing Pin Code Response
5544  * @param addr
5545  * @param pin
5546  * @return 0 if ok
5547  */
5548 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5549     return gap_pin_code_response_binary(addr, (const uint8_t*) pin, strlen(pin));
5550 }
5551 
5552 /**
5553  * @brief Abort Legacy Pairing
5554  * @param addr
5555  * @param pin
5556  * @return 0 if ok
5557  */
5558 int gap_pin_code_negative(bd_addr_t addr){
5559     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5560     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5561 }
5562 
5563 /**
5564  * @brief SSP Passkey Response
5565  * @param addr
5566  * @param passkey
5567  * @return 0 if ok
5568  */
5569 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5570     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5571     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5572     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5573 }
5574 
5575 /**
5576  * @brief Abort SSP Passkey Entry/Pairing
5577  * @param addr
5578  * @param pin
5579  * @return 0 if ok
5580  */
5581 int gap_ssp_passkey_negative(bd_addr_t addr){
5582     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5583     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5584 }
5585 
5586 /**
5587  * @brief Accept SSP Numeric Comparison
5588  * @param addr
5589  * @param passkey
5590  * @return 0 if ok
5591  */
5592 int gap_ssp_confirmation_response(bd_addr_t addr){
5593     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5594     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5595 }
5596 
5597 /**
5598  * @brief Abort SSP Numeric Comparison/Pairing
5599  * @param addr
5600  * @param pin
5601  * @return 0 if ok
5602  */
5603 int gap_ssp_confirmation_negative(bd_addr_t addr){
5604     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5605     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5606 }
5607 
5608 /**
5609  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5610  * @param inquiry_mode see bluetooth_defines.h
5611  */
5612 void hci_set_inquiry_mode(inquiry_mode_t mode){
5613     hci_stack->inquiry_mode = mode;
5614 }
5615 
5616 /**
5617  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5618  */
5619 void hci_set_sco_voice_setting(uint16_t voice_setting){
5620     hci_stack->sco_voice_setting = voice_setting;
5621 }
5622 
5623 /**
5624  * @brief Get SCO Voice Setting
5625  * @return current voice setting
5626  */
5627 uint16_t hci_get_sco_voice_setting(void){
5628     return hci_stack->sco_voice_setting;
5629 }
5630 
5631 static int hci_have_usb_transport(void){
5632     if (!hci_stack->hci_transport) return 0;
5633     const char * transport_name = hci_stack->hci_transport->name;
5634     if (!transport_name) return 0;
5635     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5636 }
5637 
5638 /** @brief Get SCO packet length for current SCO Voice setting
5639  *  @note  Using SCO packets of the exact length is required for USB transfer
5640  *  @return Length of SCO packets in bytes (not audio frames)
5641  */
5642 int hci_get_sco_packet_length(void){
5643     int sco_packet_length = 0;
5644 
5645 #ifdef ENABLE_SCO_OVER_HCI
5646 
5647     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5648     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5649 
5650     if (hci_have_usb_transport()){
5651         // see Core Spec for H2 USB Transfer.
5652         // 3 byte SCO header + 24 bytes per connection
5653         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5654         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5655     } else {
5656         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5657         sco_packet_length = 3 + 60 * multiplier;
5658         // assert that it still fits inside an SCO buffer
5659         if (sco_packet_length > hci_stack->sco_data_packet_length){
5660             sco_packet_length = 3 + 60;
5661         }
5662     }
5663 #endif
5664     return sco_packet_length;
5665 }
5666 
5667 /**
5668 * @brief Sets the master/slave policy
5669 * @param policy (0: attempt to become master, 1: let connecting device decide)
5670 */
5671 void hci_set_master_slave_policy(uint8_t policy){
5672     hci_stack->master_slave_policy = policy;
5673 }
5674 
5675 #endif
5676 
5677 HCI_STATE hci_get_state(void){
5678     return hci_stack->state;
5679 }
5680 
5681 #ifdef ENABLE_CLASSIC
5682 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5683     hci_stack->gap_classic_accept_callback = accept_callback;
5684 }
5685 #endif
5686 
5687 /**
5688  * @brief Set callback for Bluetooth Hardware Error
5689  */
5690 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5691     hci_stack->hardware_error_callback = fn;
5692 }
5693 
5694 void hci_disconnect_all(void){
5695     btstack_linked_list_iterator_t it;
5696     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5697     while (btstack_linked_list_iterator_has_next(&it)){
5698         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5699         if (con->state == SENT_DISCONNECT) continue;
5700         con->state = SEND_DISCONNECT;
5701     }
5702     hci_run();
5703 }
5704 
5705 uint16_t hci_get_manufacturer(void){
5706     return hci_stack->manufacturer;
5707 }
5708 
5709 #ifdef ENABLE_BLE
5710 
5711 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5712     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5713     if (!hci_con) return NULL;
5714     return &hci_con->sm_connection;
5715 }
5716 
5717 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5718 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5719 
5720 int gap_encryption_key_size(hci_con_handle_t con_handle){
5721     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5722     if (hci_connection == NULL) return 0;
5723     if (hci_is_le_connection(hci_connection)){
5724         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5725         if (sm_conn->sm_connection_encrypted) {
5726             return sm_conn->sm_actual_encryption_key_size;
5727         }
5728     }
5729 #ifdef ENABLE_CLASSIC
5730     else {
5731         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5732             return hci_connection->encryption_key_size;
5733         }
5734     }
5735 #endif
5736     return 0;
5737 }
5738 
5739 int gap_authenticated(hci_con_handle_t con_handle){
5740     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5741     if (hci_connection == NULL) return 0;
5742 
5743     switch (hci_connection->address_type){
5744         case BD_ADDR_TYPE_LE_PUBLIC:
5745         case BD_ADDR_TYPE_LE_RANDOM:
5746             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5747             return hci_connection->sm_connection.sm_connection_authenticated;
5748 #ifdef ENABLE_CLASSIC
5749         case BD_ADDR_TYPE_SCO:
5750         case BD_ADDR_TYPE_ACL:
5751             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5752 #endif
5753         default:
5754             return 0;
5755     }
5756 }
5757 
5758 int gap_secure_connection(hci_con_handle_t con_handle){
5759     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5760     if (hci_connection == NULL) return 0;
5761 
5762     switch (hci_connection->address_type){
5763         case BD_ADDR_TYPE_LE_PUBLIC:
5764         case BD_ADDR_TYPE_LE_RANDOM:
5765             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5766             return hci_connection->sm_connection.sm_connection_sc;
5767 #ifdef ENABLE_CLASSIC
5768         case BD_ADDR_TYPE_SCO:
5769         case BD_ADDR_TYPE_ACL:
5770             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5771 #endif
5772         default:
5773             return 0;
5774     }
5775 }
5776 
5777 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5778     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5779     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5780     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5781     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5782     return sm_conn->sm_connection_authorization_state;
5783 }
5784 #endif
5785 
5786 #ifdef ENABLE_CLASSIC
5787 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){
5788     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5789     if (!conn) return GAP_CONNECTION_INVALID;
5790     conn->sniff_min_interval = sniff_min_interval;
5791     conn->sniff_max_interval = sniff_max_interval;
5792     conn->sniff_attempt = sniff_attempt;
5793     conn->sniff_timeout = sniff_timeout;
5794     hci_run();
5795     return 0;
5796 }
5797 
5798 /**
5799  * @brief Exit Sniff mode
5800  * @param con_handle
5801  @ @return 0 if ok
5802  */
5803 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5804     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5805     if (!conn) return GAP_CONNECTION_INVALID;
5806     conn->sniff_min_interval = 0xffff;
5807     hci_run();
5808     return 0;
5809 }
5810 #endif
5811 
5812 void hci_halting_defer(void){
5813     if (hci_stack->state != HCI_STATE_HALTING) return;
5814     switch (hci_stack->substate){
5815         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5816         case HCI_HALTING_CLOSE:
5817             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5818             break;
5819         default:
5820             break;
5821     }
5822 }
5823 
5824 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5825 void hci_setup_test_connections_fuzz(void){
5826     hci_connection_t * conn;
5827 
5828     // default address: 66:55:44:33:00:01
5829     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5830 
5831     // setup Controller info
5832     hci_stack->num_cmd_packets = 255;
5833     hci_stack->acl_packets_total_num = 255;
5834 
5835     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5836     addr[5] = 0x01;
5837     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5838     conn->con_handle = addr[5];
5839     conn->role  = HCI_ROLE_SLAVE;
5840     conn->state = RECEIVED_CONNECTION_REQUEST;
5841     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5842 
5843     // setup incoming Classic SCO connection with con handle 0x0002
5844     addr[5] = 0x02;
5845     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5846     conn->con_handle = addr[5];
5847     conn->role  = HCI_ROLE_SLAVE;
5848     conn->state = RECEIVED_CONNECTION_REQUEST;
5849     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5850 
5851     // setup ready Classic ACL connection with con handle 0x0003
5852     addr[5] = 0x03;
5853     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5854     conn->con_handle = addr[5];
5855     conn->role  = HCI_ROLE_SLAVE;
5856     conn->state = OPEN;
5857     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5858 
5859     // setup ready Classic SCO connection with con handle 0x0004
5860     addr[5] = 0x04;
5861     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5862     conn->con_handle = addr[5];
5863     conn->role  = HCI_ROLE_SLAVE;
5864     conn->state = OPEN;
5865     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5866 
5867     // setup ready LE ACL connection with con handle 0x005 and public address
5868     addr[5] = 0x05;
5869     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5870     conn->con_handle = addr[5];
5871     conn->role  = HCI_ROLE_SLAVE;
5872     conn->state = OPEN;
5873     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5874 }
5875 
5876 void hci_free_connections_fuzz(void){
5877     btstack_linked_list_iterator_t it;
5878     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5879     while (btstack_linked_list_iterator_has_next(&it)){
5880         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5881         btstack_linked_list_iterator_remove(&it);
5882         btstack_memory_hci_connection_free(con);
5883     }
5884 }
5885 void hci_simulate_working_fuzz(void){
5886     hci_init_done();
5887     hci_stack->num_cmd_packets = 255;
5888 }
5889 #endif
5890