xref: /btstack/src/hci.c (revision 5d23aae8c99ae76ea4cbc60923752604dceb7324)
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 <stdio.h>
67 #include <inttypes.h>
68 
69 #include "btstack_debug.h"
70 #include "btstack_event.h"
71 #include "btstack_linked_list.h"
72 #include "btstack_memory.h"
73 #include "bluetooth_company_id.h"
74 #include "bluetooth_data_types.h"
75 #include "gap.h"
76 #include "hci.h"
77 #include "hci_cmd.h"
78 #include "hci_dump.h"
79 #include "ad_parser.h"
80 
81 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
82 #ifndef HCI_HOST_ACL_PACKET_NUM
83 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
84 #endif
85 #ifndef HCI_HOST_ACL_PACKET_LEN
86 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
87 #endif
88 #ifndef HCI_HOST_SCO_PACKET_NUM
89 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
90 #endif
91 #ifndef HCI_HOST_SCO_PACKET_LEN
92 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
93 #endif
94 #endif
95 
96 #define HCI_CONNECTION_TIMEOUT_MS 10000
97 
98 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
99 #define HCI_RESET_RESEND_TIMEOUT_MS 200
100 #endif
101 
102 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
103 #ifndef GAP_INQUIRY_MAX_NAME_LEN
104 #define GAP_INQUIRY_MAX_NAME_LEN 32
105 #endif
106 
107 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
108 #define GAP_INQUIRY_DURATION_MIN 0x01
109 #define GAP_INQUIRY_DURATION_MAX 0x30
110 #define GAP_INQUIRY_STATE_ACTIVE 0x80
111 #define GAP_INQUIRY_STATE_IDLE 0
112 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
113 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
114 
115 // GAP Remote Name Request
116 #define GAP_REMOTE_NAME_STATE_IDLE 0
117 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
118 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
119 
120 // GAP Pairing
121 #define GAP_PAIRING_STATE_IDLE                       0
122 #define GAP_PAIRING_STATE_SEND_PIN                   1
123 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
124 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
125 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
127 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
128 
129 
130 // prototypes
131 #ifdef ENABLE_CLASSIC
132 static void hci_update_scan_enable(void);
133 static void hci_emit_discoverable_enabled(uint8_t enabled);
134 static int  hci_local_ssp_activated(void);
135 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
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 void hci_remove_from_whitelist(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->address_type = addr_type;
198     conn->con_handle = 0xffff;
199     conn->authentication_flags = AUTH_FLAGS_NONE;
200     conn->bonding_flags = 0;
201     conn->requested_security_level = LEVEL_0;
202 #ifdef ENABLE_CLASSIC
203     btstack_run_loop_set_timer_handler(&conn->timeout, hci_connection_timeout_handler);
204     btstack_run_loop_set_timer_context(&conn->timeout, conn);
205     hci_connection_timestamp(conn);
206 #endif
207     conn->acl_recombination_length = 0;
208     conn->acl_recombination_pos = 0;
209     conn->num_packets_sent = 0;
210 
211     conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
212 #ifdef ENABLE_BLE
213     conn->le_phy_update_all_phys = 0xff;
214 #endif
215 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
216     conn->le_max_tx_octets = 27;
217 #endif
218     btstack_linked_list_add(&hci_stack->connections, (btstack_linked_item_t *) conn);
219     return conn;
220 }
221 
222 
223 /**
224  * get le connection parameter range
225 *
226  * @return le connection parameter range struct
227  */
228 void gap_get_connection_parameter_range(le_connection_parameter_range_t * range){
229     *range = hci_stack->le_connection_parameter_range;
230 }
231 
232 /**
233  * set le connection parameter range
234  *
235  */
236 
237 void gap_set_connection_parameter_range(le_connection_parameter_range_t *range){
238     hci_stack->le_connection_parameter_range = *range;
239 }
240 
241 /**
242  * @brief Test if connection parameters are inside in existing rage
243  * @param conn_interval_min (unit: 1.25ms)
244  * @param conn_interval_max (unit: 1.25ms)
245  * @param conn_latency
246  * @param supervision_timeout (unit: 10ms)
247  * @returns 1 if included
248  */
249 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){
250     if (le_conn_interval_min < existing_range->le_conn_interval_min) return 0;
251     if (le_conn_interval_max > existing_range->le_conn_interval_max) return 0;
252 
253     if (le_conn_latency < existing_range->le_conn_latency_min) return 0;
254     if (le_conn_latency > existing_range->le_conn_latency_max) return 0;
255 
256     if (le_supervision_timeout < existing_range->le_supervision_timeout_min) return 0;
257     if (le_supervision_timeout > existing_range->le_supervision_timeout_max) return 0;
258 
259     return 1;
260 }
261 
262 /**
263  * @brief Set max number of connections in LE Peripheral role (if Bluetooth Controller supports it)
264  * @note: default: 1
265  * @param max_peripheral_connections
266  */
267 #ifdef ENABLE_LE_PERIPHERAL
268 void gap_set_max_number_peripheral_connections(int max_peripheral_connections){
269     hci_stack->le_max_number_peripheral_connections = max_peripheral_connections;
270 }
271 #endif
272 
273 /**
274  * get hci connections iterator
275  *
276  * @return hci connections iterator
277  */
278 
279 void hci_connections_get_iterator(btstack_linked_list_iterator_t *it){
280     btstack_linked_list_iterator_init(it, &hci_stack->connections);
281 }
282 
283 /**
284  * get connection for a given handle
285  *
286  * @return connection OR NULL, if not found
287  */
288 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
289     btstack_linked_list_iterator_t it;
290     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
291     while (btstack_linked_list_iterator_has_next(&it)){
292         hci_connection_t * item = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
293         if ( item->con_handle == con_handle ) {
294             return item;
295         }
296     }
297     return NULL;
298 }
299 
300 /**
301  * get connection for given address
302  *
303  * @return connection OR NULL, if not found
304  */
305 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t  addr, bd_addr_type_t addr_type){
306     btstack_linked_list_iterator_t it;
307     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
308     while (btstack_linked_list_iterator_has_next(&it)){
309         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
310         if (connection->address_type != addr_type)  continue;
311         if (memcmp(addr, connection->address, 6) != 0) continue;
312         return connection;
313     }
314     return NULL;
315 }
316 
317 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
318     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
319 }
320 
321 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
322     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
323 }
324 
325 #ifdef ENABLE_CLASSIC
326 
327 #ifdef ENABLE_SCO_OVER_HCI
328 static int hci_number_sco_connections(void){
329     int connections = 0;
330     btstack_linked_list_iterator_t it;
331     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
332     while (btstack_linked_list_iterator_has_next(&it)){
333         hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it);
334         if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
335         connections++;
336     }
337     return connections;
338 }
339 #endif
340 
341 static void hci_connection_timeout_handler(btstack_timer_source_t *timer){
342     hci_connection_t * connection = (hci_connection_t *) btstack_run_loop_get_timer_context(timer);
343 #ifdef HAVE_EMBEDDED_TICK
344     if (btstack_run_loop_embedded_get_ticks() > connection->timestamp + btstack_run_loop_embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
345         // connections might be timed out
346         hci_emit_l2cap_check_timeout(connection);
347     }
348 #else
349     if (btstack_run_loop_get_time_ms() > (connection->timestamp + HCI_CONNECTION_TIMEOUT_MS)){
350         // connections might be timed out
351         hci_emit_l2cap_check_timeout(connection);
352     }
353 #endif
354 }
355 
356 static void hci_connection_timestamp(hci_connection_t *connection){
357 #ifdef HAVE_EMBEDDED_TICK
358     connection->timestamp = btstack_run_loop_embedded_get_ticks();
359 #else
360     connection->timestamp = btstack_run_loop_get_time_ms();
361 #endif
362 }
363 
364 /**
365  * add authentication flags and reset timer
366  * @note: assumes classic connection
367  * @note: bd_addr is passed in as litle endian uint8_t * as it is called from parsing packets
368  */
369 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
370     bd_addr_t addr;
371     reverse_bd_addr(bd_addr, addr);
372     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
373     if (conn) {
374         connectionSetAuthenticationFlags(conn, flags);
375         hci_connection_timestamp(conn);
376     }
377 }
378 
379 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
380     hci_connection_t * conn = hci_connection_for_handle(handle);
381     if (!conn) return 0;
382     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
383     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
384     return 0;
385 }
386 
387 void gap_drop_link_key_for_bd_addr(bd_addr_t addr){
388     if (!hci_stack->link_key_db) return;
389     log_info("gap_drop_link_key_for_bd_addr: %s", bd_addr_to_str(addr));
390     hci_stack->link_key_db->delete_link_key(addr);
391 }
392 
393 void gap_store_link_key_for_bd_addr(bd_addr_t addr, link_key_t link_key, link_key_type_t type){
394     if (!hci_stack->link_key_db) return;
395     log_info("gap_store_link_key_for_bd_addr: %s, type %u", bd_addr_to_str(addr), type);
396     hci_stack->link_key_db->put_link_key(addr, link_key, type);
397 }
398 
399 void gap_delete_all_link_keys(void){
400     bd_addr_t  addr;
401     link_key_t link_key;
402     link_key_type_t type;
403     btstack_link_key_iterator_t it;
404     int ok = gap_link_key_iterator_init(&it);
405     if (!ok) {
406         log_error("could not initialize iterator");
407         return;
408     }
409     while (gap_link_key_iterator_get_next(&it, addr, link_key, &type)){
410         gap_drop_link_key_for_bd_addr(addr);
411     }
412     gap_link_key_iterator_done(&it);
413 }
414 
415 int gap_link_key_iterator_init(btstack_link_key_iterator_t * it){
416     if (!hci_stack->link_key_db) return 0;
417     if (!hci_stack->link_key_db->iterator_init) return 0;
418     return hci_stack->link_key_db->iterator_init(it);
419 }
420 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){
421     if (!hci_stack->link_key_db) return 0;
422     return hci_stack->link_key_db->iterator_get_next(it, bd_addr, link_key, type);
423 }
424 void gap_link_key_iterator_done(btstack_link_key_iterator_t * it){
425     if (!hci_stack->link_key_db) return;
426     hci_stack->link_key_db->iterator_done(it);
427 }
428 #endif
429 
430 static int hci_is_le_connection(hci_connection_t * connection){
431     switch (connection->address_type){
432         case BD_ADDR_TYPE_LE_PUBLIC:
433         case BD_ADDR_TYPE_LE_RANDOM:
434         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_PUBLIC:
435         case BD_ADDR_TYPE_LE_PRIVAT_FALLBACK_RANDOM:
436             return 1;
437         default:
438             return 0;
439     }
440 }
441 
442 /**
443  * count connections
444  */
445 static int nr_hci_connections(void){
446     int count = 0;
447     btstack_linked_item_t *it;
448     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL ; it = it->next){
449         count++;
450     }
451     return count;
452 }
453 
454 static int hci_number_free_acl_slots_for_connection_type(bd_addr_type_t address_type){
455 
456     unsigned int num_packets_sent_classic = 0;
457     unsigned int num_packets_sent_le = 0;
458 
459     btstack_linked_item_t *it;
460     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
461         hci_connection_t * connection = (hci_connection_t *) it;
462         if (hci_is_le_connection(connection)){
463             num_packets_sent_le += connection->num_packets_sent;
464         }
465         if (connection->address_type == BD_ADDR_TYPE_ACL){
466             num_packets_sent_classic += connection->num_packets_sent;
467         }
468     }
469     log_debug("ACL classic buffers: %u used of %u", num_packets_sent_classic, hci_stack->acl_packets_total_num);
470     int free_slots_classic = hci_stack->acl_packets_total_num - num_packets_sent_classic;
471     int free_slots_le = 0;
472 
473     if (free_slots_classic < 0){
474         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);
475         return 0;
476     }
477 
478     if (hci_stack->le_acl_packets_total_num){
479         // if we have LE slots, they are used
480         free_slots_le = hci_stack->le_acl_packets_total_num - num_packets_sent_le;
481         if (free_slots_le < 0){
482             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);
483             return 0;
484         }
485     } else {
486         // otherwise, classic slots are used for LE, too
487         free_slots_classic -= num_packets_sent_le;
488         if (free_slots_classic < 0){
489             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);
490             return 0;
491         }
492     }
493 
494     switch (address_type){
495         case BD_ADDR_TYPE_UNKNOWN:
496             log_error("hci_number_free_acl_slots: unknown address type");
497             return 0;
498 
499         case BD_ADDR_TYPE_ACL:
500             return free_slots_classic;
501 
502         default:
503            if (hci_stack->le_acl_packets_total_num){
504                return free_slots_le;
505            }
506            return free_slots_classic;
507     }
508 }
509 
510 int hci_number_free_acl_slots_for_handle(hci_con_handle_t con_handle){
511     // get connection type
512     hci_connection_t * connection = hci_connection_for_handle(con_handle);
513     if (!connection){
514         log_error("hci_number_free_acl_slots: handle 0x%04x not in connection list", con_handle);
515         return 0;
516     }
517     return hci_number_free_acl_slots_for_connection_type(connection->address_type);
518 }
519 
520 #ifdef ENABLE_CLASSIC
521 static int hci_number_free_sco_slots(void){
522     unsigned int num_sco_packets_sent  = 0;
523     btstack_linked_item_t *it;
524     if (hci_stack->synchronous_flow_control_enabled){
525         // explicit flow control
526         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
527             hci_connection_t * connection = (hci_connection_t *) it;
528             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
529             num_sco_packets_sent += connection->num_packets_sent;
530         }
531         if (num_sco_packets_sent > hci_stack->sco_packets_total_num){
532             log_info("hci_number_free_sco_slots:packets (%u) > total packets (%u)", num_sco_packets_sent, hci_stack->sco_packets_total_num);
533             return 0;
534         }
535         return hci_stack->sco_packets_total_num - num_sco_packets_sent;
536     } else {
537         // implicit flow control -- TODO
538         int num_ready = 0;
539         for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
540             hci_connection_t * connection = (hci_connection_t *) it;
541             if (connection->address_type != BD_ADDR_TYPE_SCO) continue;
542             if (connection->sco_tx_ready == 0) continue;
543             num_ready++;
544         }
545         return num_ready;
546     }
547 }
548 #endif
549 
550 // only used to send HCI Host Number Completed Packets
551 static int hci_can_send_comand_packet_transport(void){
552     if (hci_stack->hci_packet_buffer_reserved) return 0;
553 
554     // check for async hci transport implementations
555     if (hci_stack->hci_transport->can_send_packet_now){
556         if (!hci_stack->hci_transport->can_send_packet_now(HCI_COMMAND_DATA_PACKET)){
557             return 0;
558         }
559     }
560     return 1;
561 }
562 
563 // new functions replacing hci_can_send_packet_now[_using_packet_buffer]
564 int hci_can_send_command_packet_now(void){
565     if (hci_can_send_comand_packet_transport() == 0) return 0;
566     return hci_stack->num_cmd_packets > 0;
567 }
568 
569 static int hci_transport_can_send_prepared_packet_now(uint8_t packet_type){
570     // check for async hci transport implementations
571     if (!hci_stack->hci_transport->can_send_packet_now) return 1;
572     return hci_stack->hci_transport->can_send_packet_now(packet_type);
573 }
574 
575 static int hci_can_send_prepared_acl_packet_for_address_type(bd_addr_type_t address_type){
576     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
577     return hci_number_free_acl_slots_for_connection_type(address_type) > 0;
578 }
579 
580 int hci_can_send_acl_le_packet_now(void){
581     if (hci_stack->hci_packet_buffer_reserved) return 0;
582     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_LE_PUBLIC);
583 }
584 
585 int hci_can_send_prepared_acl_packet_now(hci_con_handle_t con_handle) {
586     if (!hci_transport_can_send_prepared_packet_now(HCI_ACL_DATA_PACKET)) return 0;
587     return hci_number_free_acl_slots_for_handle(con_handle) > 0;
588 }
589 
590 int hci_can_send_acl_packet_now(hci_con_handle_t con_handle){
591     if (hci_stack->hci_packet_buffer_reserved) return 0;
592     return hci_can_send_prepared_acl_packet_now(con_handle);
593 }
594 
595 #ifdef ENABLE_CLASSIC
596 int hci_can_send_acl_classic_packet_now(void){
597     if (hci_stack->hci_packet_buffer_reserved) return 0;
598     return hci_can_send_prepared_acl_packet_for_address_type(BD_ADDR_TYPE_ACL);
599 }
600 
601 int hci_can_send_prepared_sco_packet_now(void){
602     if (!hci_transport_can_send_prepared_packet_now(HCI_SCO_DATA_PACKET)) return 0;
603     if (hci_have_usb_transport()){
604         return hci_stack->sco_can_send_now;
605     } else {
606         return hci_number_free_sco_slots() > 0;
607     }
608 }
609 
610 int hci_can_send_sco_packet_now(void){
611     if (hci_stack->hci_packet_buffer_reserved) return 0;
612     return hci_can_send_prepared_sco_packet_now();
613 }
614 
615 void hci_request_sco_can_send_now_event(void){
616     hci_stack->sco_waiting_for_can_send_now = 1;
617     hci_notify_if_sco_can_send_now();
618 }
619 #endif
620 
621 // used for internal checks in l2cap.c
622 int hci_is_packet_buffer_reserved(void){
623     return hci_stack->hci_packet_buffer_reserved;
624 }
625 
626 // reserves outgoing packet buffer. @returns 1 if successful
627 int hci_reserve_packet_buffer(void){
628     if (hci_stack->hci_packet_buffer_reserved) {
629         log_error("hci_reserve_packet_buffer called but buffer already reserved");
630         return 0;
631     }
632     hci_stack->hci_packet_buffer_reserved = 1;
633     return 1;
634 }
635 
636 void hci_release_packet_buffer(void){
637     hci_stack->hci_packet_buffer_reserved = 0;
638 }
639 
640 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
641 static int hci_transport_synchronous(void){
642     return hci_stack->hci_transport->can_send_packet_now == NULL;
643 }
644 
645 static int hci_send_acl_packet_fragments(hci_connection_t *connection){
646 
647     // 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);
648 
649     // max ACL data packet length depends on connection type (LE vs. Classic) and available buffers
650     uint16_t max_acl_data_packet_length = hci_stack->acl_data_packet_length;
651     if (hci_is_le_connection(connection) && (hci_stack->le_data_packets_length > 0)){
652         max_acl_data_packet_length = hci_stack->le_data_packets_length;
653     }
654 
655 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
656     if (hci_is_le_connection(connection)){
657         max_acl_data_packet_length = connection->le_max_tx_octets;
658     }
659 #endif
660 
661     log_debug("hci_send_acl_packet_fragments entered");
662 
663     int err;
664     // multiple packets could be send on a synchronous HCI transport
665     while (true){
666 
667         log_debug("hci_send_acl_packet_fragments loop entered");
668 
669         // get current data
670         const uint16_t acl_header_pos = hci_stack->acl_fragmentation_pos - 4;
671         int current_acl_data_packet_length = hci_stack->acl_fragmentation_total_size - hci_stack->acl_fragmentation_pos;
672         int more_fragments = 0;
673 
674         // if ACL packet is larger than Bluetooth packet buffer, only send max_acl_data_packet_length
675         if (current_acl_data_packet_length > max_acl_data_packet_length){
676             more_fragments = 1;
677             current_acl_data_packet_length = max_acl_data_packet_length;
678         }
679 
680         // copy handle_and_flags if not first fragment and update packet boundary flags to be 01 (continuing fragmnent)
681         if (acl_header_pos > 0){
682             uint16_t handle_and_flags = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
683             handle_and_flags = (handle_and_flags & 0xcfff) | (1 << 12);
684             little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos, handle_and_flags);
685         }
686 
687         // update header len
688         little_endian_store_16(hci_stack->hci_packet_buffer, acl_header_pos + 2, current_acl_data_packet_length);
689 
690         // count packet
691         connection->num_packets_sent++;
692         log_debug("hci_send_acl_packet_fragments loop before send (more fragments %d)", more_fragments);
693 
694         // update state for next fragment (if any) as "transport done" might be sent during send_packet already
695         if (more_fragments){
696             // update start of next fragment to send
697             hci_stack->acl_fragmentation_pos += current_acl_data_packet_length;
698         } else {
699             // done
700             hci_stack->acl_fragmentation_pos = 0;
701             hci_stack->acl_fragmentation_total_size = 0;
702         }
703 
704         // send packet
705         uint8_t * packet = &hci_stack->hci_packet_buffer[acl_header_pos];
706         const int size = current_acl_data_packet_length + 4;
707         hci_dump_packet(HCI_ACL_DATA_PACKET, 0, packet, size);
708         hci_stack->acl_fragmentation_tx_active = 1;
709         err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
710 
711         log_debug("hci_send_acl_packet_fragments loop after send (more fragments %d)", more_fragments);
712 
713         // done yet?
714         if (!more_fragments) break;
715 
716         // can send more?
717         if (!hci_can_send_prepared_acl_packet_now(connection->con_handle)) return err;
718     }
719 
720     log_debug("hci_send_acl_packet_fragments loop over");
721 
722     // release buffer now for synchronous transport
723     if (hci_transport_synchronous()){
724         hci_stack->acl_fragmentation_tx_active = 0;
725         hci_release_packet_buffer();
726         hci_emit_transport_packet_sent();
727     }
728 
729     return err;
730 }
731 
732 // pre: caller has reserved the packet buffer
733 int hci_send_acl_packet_buffer(int size){
734 
735     // log_info("hci_send_acl_packet_buffer size %u", size);
736 
737     if (!hci_stack->hci_packet_buffer_reserved) {
738         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
739         return 0;
740     }
741 
742     uint8_t * packet = hci_stack->hci_packet_buffer;
743     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
744 
745     // check for free places on Bluetooth module
746     if (!hci_can_send_prepared_acl_packet_now(con_handle)) {
747         log_error("hci_send_acl_packet_buffer called but no free ACL buffers on controller");
748         hci_release_packet_buffer();
749         hci_emit_transport_packet_sent();
750         return BTSTACK_ACL_BUFFERS_FULL;
751     }
752 
753     hci_connection_t *connection = hci_connection_for_handle( con_handle);
754     if (!connection) {
755         log_error("hci_send_acl_packet_buffer called but no connection for handle 0x%04x", con_handle);
756         hci_release_packet_buffer();
757         hci_emit_transport_packet_sent();
758         return 0;
759     }
760 
761 #ifdef ENABLE_CLASSIC
762     hci_connection_timestamp(connection);
763 #endif
764 
765     // hci_dump_packet( HCI_ACL_DATA_PACKET, 0, packet, size);
766 
767     // setup data
768     hci_stack->acl_fragmentation_total_size = size;
769     hci_stack->acl_fragmentation_pos = 4;   // start of L2CAP packet
770 
771     return hci_send_acl_packet_fragments(connection);
772 }
773 
774 #ifdef ENABLE_CLASSIC
775 // pre: caller has reserved the packet buffer
776 int hci_send_sco_packet_buffer(int size){
777 
778     // log_info("hci_send_acl_packet_buffer size %u", size);
779 
780     if (!hci_stack->hci_packet_buffer_reserved) {
781         log_error("hci_send_acl_packet_buffer called without reserving packet buffer");
782         return 0;
783     }
784 
785     uint8_t * packet = hci_stack->hci_packet_buffer;
786 
787     // skip checks in loopback mode
788     if (!hci_stack->loopback_mode){
789         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);   // same for ACL and SCO
790 
791         // check for free places on Bluetooth module
792         if (!hci_can_send_prepared_sco_packet_now()) {
793             log_error("hci_send_sco_packet_buffer called but no free SCO buffers on controller");
794             hci_release_packet_buffer();
795             hci_emit_transport_packet_sent();
796             return BTSTACK_ACL_BUFFERS_FULL;
797         }
798 
799         // track send packet in connection struct
800         hci_connection_t *connection = hci_connection_for_handle( con_handle);
801         if (!connection) {
802             log_error("hci_send_sco_packet_buffer called but no connection for handle 0x%04x", con_handle);
803             hci_release_packet_buffer();
804             hci_emit_transport_packet_sent();
805             return 0;
806         }
807 
808         if (hci_have_usb_transport()){
809             // token used
810             hci_stack->sco_can_send_now = 0;
811         } else {
812             if (hci_stack->synchronous_flow_control_enabled){
813                 connection->num_packets_sent++;
814             } else {
815                 connection->sco_tx_ready--;
816             }
817         }
818     }
819 
820     hci_dump_packet( HCI_SCO_DATA_PACKET, 0, packet, size);
821     int err = hci_stack->hci_transport->send_packet(HCI_SCO_DATA_PACKET, packet, size);
822 
823     if (hci_transport_synchronous()){
824         hci_release_packet_buffer();
825         hci_emit_transport_packet_sent();
826     }
827 
828     return err;
829 }
830 #endif
831 
832 static void acl_handler(uint8_t *packet, int size){
833 
834     // log_info("acl_handler: size %u", size);
835 
836     // get info
837     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
838     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
839     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
840     uint16_t acl_length         = READ_ACL_LENGTH(packet);
841 
842     // ignore non-registered handle
843     if (!conn){
844         log_error( "hci.c: acl_handler called with non-registered handle %u!" , con_handle);
845         return;
846     }
847 
848     // assert packet is complete
849     if ((acl_length + 4) != size){
850         log_error("hci.c: acl_handler called with ACL packet of wrong size %d, expected %u => dropping packet", size, acl_length + 4);
851         return;
852     }
853 
854 #ifdef ENABLE_CLASSIC
855     // update idle timestamp
856     hci_connection_timestamp(conn);
857 #endif
858 
859 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
860     hci_stack->host_completed_packets = 1;
861     conn->num_packets_completed++;
862 #endif
863 
864     // handle different packet types
865     switch (acl_flags & 0x03) {
866 
867         case 0x01: // continuation fragment
868 
869             // sanity checks
870             if (conn->acl_recombination_pos == 0) {
871                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x", con_handle);
872                 return;
873             }
874             if ((conn->acl_recombination_pos + acl_length) > (4 + HCI_ACL_BUFFER_SIZE)){
875                 log_error( "ACL Cont Fragment to large: combined packet %u > buffer size %u for handle 0x%02x",
876                     conn->acl_recombination_pos + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
877                 conn->acl_recombination_pos = 0;
878                 return;
879             }
880 
881             // append fragment payload (header already stored)
882             (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE + conn->acl_recombination_pos],
883                          &packet[4], acl_length);
884             conn->acl_recombination_pos += acl_length;
885 
886             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u", acl_length,
887             //        conn->acl_recombination_pos, conn->acl_recombination_length);
888 
889             // forward complete L2CAP packet if complete.
890             if (conn->acl_recombination_pos >= (conn->acl_recombination_length + 4 + 4)){ // pos already incl. ACL header
891                 hci_emit_acl_packet(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE], conn->acl_recombination_pos);
892                 // reset recombination buffer
893                 conn->acl_recombination_length = 0;
894                 conn->acl_recombination_pos = 0;
895             }
896             break;
897 
898         case 0x02: { // first fragment
899 
900             // sanity check
901             if (conn->acl_recombination_pos) {
902                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x, dropping stale fragments", con_handle);
903                 conn->acl_recombination_pos = 0;
904             }
905 
906             // peek into L2CAP packet!
907             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
908 
909             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u", acl_length, l2cap_length);
910 
911             // compare fragment size to L2CAP packet size
912             if (acl_length >= (l2cap_length + 4)){
913                 // forward fragment as L2CAP packet
914                 hci_emit_acl_packet(packet, acl_length + 4);
915             } else {
916 
917                 if (acl_length > HCI_ACL_BUFFER_SIZE){
918                     log_error( "ACL First Fragment to large: fragment %u > buffer size %u for handle 0x%02x",
919                         4 + acl_length, 4 + HCI_ACL_BUFFER_SIZE, con_handle);
920                     return;
921                 }
922 
923                 // store first fragment and tweak acl length for complete package
924                 (void)memcpy(&conn->acl_recombination_buffer[HCI_INCOMING_PRE_BUFFER_SIZE],
925                              packet, acl_length + 4);
926                 conn->acl_recombination_pos    = acl_length + 4;
927                 conn->acl_recombination_length = l2cap_length;
928                 little_endian_store_16(conn->acl_recombination_buffer, HCI_INCOMING_PRE_BUFFER_SIZE + 2, l2cap_length +4);
929             }
930             break;
931 
932         }
933         default:
934             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u", acl_flags & 0x03);
935             return;
936     }
937 
938     // execute main loop
939     hci_run();
940 }
941 
942 static void hci_shutdown_connection(hci_connection_t *conn){
943     log_info("Connection closed: handle 0x%x, %s", conn->con_handle, bd_addr_to_str(conn->address));
944 
945 #ifdef ENABLE_CLASSIC
946 #ifdef ENABLE_SCO_OVER_HCI
947     int addr_type = conn->address_type;
948 #endif
949 #endif
950 
951     btstack_run_loop_remove_timer(&conn->timeout);
952 
953     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
954     btstack_memory_hci_connection_free( conn );
955 
956     // now it's gone
957     hci_emit_nr_connections_changed();
958 
959 #ifdef ENABLE_CLASSIC
960 #ifdef ENABLE_SCO_OVER_HCI
961     // update SCO
962     if (addr_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
963         hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
964     }
965 #endif
966 #endif
967 }
968 
969 #ifdef ENABLE_CLASSIC
970 
971 static const uint16_t packet_type_sizes[] = {
972     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
973     HCI_ACL_DH1_SIZE, 0, 0, 0,
974     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
975     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
976 };
977 static const uint8_t  packet_type_feature_requirement_bit[] = {
978      0, // 3 slot packets
979      1, // 5 slot packets
980     25, // EDR 2 mpbs
981     26, // EDR 3 mbps
982     39, // 3 slot EDR packts
983     40, // 5 slot EDR packet
984 };
985 static const uint16_t packet_type_feature_packet_mask[] = {
986     0x0f00, // 3 slot packets
987     0xf000, // 5 slot packets
988     0x1102, // EDR 2 mpbs
989     0x2204, // EDR 3 mbps
990     0x0300, // 3 slot EDR packts
991     0x3000, // 5 slot EDR packet
992 };
993 
994 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
995     // enable packet types based on size
996     uint16_t packet_types = 0;
997     unsigned int i;
998     for (i=0;i<16;i++){
999         if (packet_type_sizes[i] == 0) continue;
1000         if (packet_type_sizes[i] <= buffer_size){
1001             packet_types |= 1 << i;
1002         }
1003     }
1004     // disable packet types due to missing local supported features
1005     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
1006         unsigned int bit_idx = packet_type_feature_requirement_bit[i];
1007         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
1008         if (feature_set) continue;
1009         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
1010         packet_types &= ~packet_type_feature_packet_mask[i];
1011     }
1012     // flip bits for "may not be used"
1013     packet_types ^= 0x3306;
1014     return packet_types;
1015 }
1016 
1017 uint16_t hci_usable_acl_packet_types(void){
1018     return hci_stack->packet_types;
1019 }
1020 #endif
1021 
1022 uint8_t* hci_get_outgoing_packet_buffer(void){
1023     // hci packet buffer is >= acl data packet length
1024     return hci_stack->hci_packet_buffer;
1025 }
1026 
1027 uint16_t hci_max_acl_data_packet_length(void){
1028     return hci_stack->acl_data_packet_length;
1029 }
1030 
1031 #ifdef ENABLE_CLASSIC
1032 int hci_extended_sco_link_supported(void){
1033     // No. 31, byte 3, bit 7
1034     return (hci_stack->local_supported_features[3] & (1 << 7)) != 0;
1035 }
1036 #endif
1037 
1038 int hci_non_flushable_packet_boundary_flag_supported(void){
1039     // No. 54, byte 6, bit 6
1040     return (hci_stack->local_supported_features[6] & (1 << 6)) != 0;
1041 }
1042 
1043 static int gap_ssp_supported(void){
1044     // No. 51, byte 6, bit 3
1045     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
1046 }
1047 
1048 static int hci_classic_supported(void){
1049 #ifdef ENABLE_CLASSIC
1050     // No. 37, byte 4, bit 5, = No BR/EDR Support
1051     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
1052 #else
1053     return 0;
1054 #endif
1055 }
1056 
1057 static int hci_le_supported(void){
1058 #ifdef ENABLE_BLE
1059     // No. 37, byte 4, bit 6 = LE Supported (Controller)
1060     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
1061 #else
1062     return 0;
1063 #endif
1064 }
1065 
1066 #ifdef ENABLE_BLE
1067 
1068 /**
1069  * @brief Get addr type and address used for LE in Advertisements, Scan Responses,
1070  */
1071 void gap_le_get_own_address(uint8_t * addr_type, bd_addr_t addr){
1072     *addr_type = hci_stack->le_own_addr_type;
1073     if (hci_stack->le_own_addr_type){
1074         (void)memcpy(addr, hci_stack->le_random_address, 6);
1075     } else {
1076         (void)memcpy(addr, hci_stack->local_bd_addr, 6);
1077     }
1078 }
1079 
1080 #ifdef ENABLE_LE_CENTRAL
1081 void le_handle_advertisement_report(uint8_t *packet, uint16_t size){
1082 
1083     int offset = 3;
1084     int num_reports = packet[offset];
1085     offset += 1;
1086 
1087     int i;
1088     // log_info("HCI: handle adv report with num reports: %d", num_reports);
1089     uint8_t event[12 + LE_ADVERTISING_DATA_SIZE]; // use upper bound to avoid var size automatic var
1090     for (i=0; (i<num_reports) && (offset < size);i++){
1091         // sanity checks on data_length:
1092         uint8_t data_length = packet[offset + 8];
1093         if (data_length > LE_ADVERTISING_DATA_SIZE) return;
1094         if ((offset + 9 + data_length + 1) > size)    return;
1095         // setup event
1096         uint8_t event_size = 10 + data_length;
1097         int pos = 0;
1098         event[pos++] = GAP_EVENT_ADVERTISING_REPORT;
1099         event[pos++] = event_size;
1100         (void)memcpy(&event[pos], &packet[offset], 1 + 1 + 6); // event type + address type + address
1101         offset += 8;
1102         pos += 8;
1103         event[pos++] = packet[offset + 1 + data_length]; // rssi
1104         event[pos++] = data_length;
1105         offset++;
1106         (void)memcpy(&event[pos], &packet[offset], data_length);
1107         pos +=    data_length;
1108         offset += data_length + 1; // rssi
1109         hci_emit_event(event, pos, 1);
1110     }
1111 }
1112 #endif
1113 #endif
1114 
1115 #ifdef ENABLE_BLE
1116 #ifdef ENABLE_LE_PERIPHERAL
1117 static void hci_reenable_advertisements_if_needed(void){
1118     if (!hci_stack->le_advertisements_active && hci_stack->le_advertisements_enabled){
1119         // get number of active le slave connections
1120         int num_slave_connections = 0;
1121         btstack_linked_list_iterator_t it;
1122         btstack_linked_list_iterator_init(&it, &hci_stack->connections);
1123         while (btstack_linked_list_iterator_has_next(&it)){
1124             hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
1125             log_info("state %u, role %u, le_con %u", con->state, con->role, hci_is_le_connection(con));
1126             if (con->state != OPEN) continue;
1127             if (con->role  != HCI_ROLE_SLAVE) continue;
1128             if (!hci_is_le_connection(con)) continue;
1129             num_slave_connections++;
1130         }
1131         log_info("Num LE Peripheral roles: %u of %u", num_slave_connections, hci_stack->le_max_number_peripheral_connections);
1132         if (num_slave_connections < hci_stack->le_max_number_peripheral_connections){
1133             hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
1134         }
1135     }
1136 }
1137 #endif
1138 #endif
1139 
1140 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1141 
1142 static uint32_t hci_transport_uart_get_main_baud_rate(void){
1143     if (!hci_stack->config) return 0;
1144     uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1145     // Limit baud rate for Broadcom chipsets to 3 mbps
1146     if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) && (baud_rate > 3000000)){
1147         baud_rate = 3000000;
1148     }
1149     return baud_rate;
1150 }
1151 
1152 static void hci_initialization_timeout_handler(btstack_timer_source_t * ds){
1153     UNUSED(ds);
1154 
1155     switch (hci_stack->substate){
1156         case HCI_INIT_W4_SEND_RESET:
1157             log_info("Resend HCI Reset");
1158             hci_stack->substate = HCI_INIT_SEND_RESET;
1159             hci_stack->num_cmd_packets = 1;
1160             hci_run();
1161             break;
1162         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET:
1163             log_info("Resend HCI Reset - CSR Warm Boot with Link Reset");
1164             if (hci_stack->hci_transport->reset_link){
1165                 hci_stack->hci_transport->reset_link();
1166             }
1167 
1168             /* fall through */
1169 
1170         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1171             log_info("Resend HCI Reset - CSR Warm Boot");
1172             hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1173             hci_stack->num_cmd_packets = 1;
1174             hci_run();
1175             break;
1176         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1177             if (hci_stack->hci_transport->set_baudrate){
1178                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1179                 log_info("Local baud rate change to %"PRIu32"(timeout handler)", baud_rate);
1180                 hci_stack->hci_transport->set_baudrate(baud_rate);
1181             }
1182             // For CSR, HCI Reset is sent on new baud rate. Don't forget to reset link for H5/BCSP
1183             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
1184                 if (hci_stack->hci_transport->reset_link){
1185                     log_info("Link Reset");
1186                     hci_stack->hci_transport->reset_link();
1187                 }
1188                 hci_stack->substate = HCI_INIT_SEND_RESET_CSR_WARM_BOOT;
1189                 hci_run();
1190             }
1191             break;
1192         case HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY:
1193             // otherwise continue
1194             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1195             hci_send_cmd(&hci_read_local_supported_commands);
1196             break;
1197         default:
1198             break;
1199     }
1200 }
1201 #endif
1202 
1203 static void hci_initializing_next_state(void){
1204     hci_stack->substate = (hci_substate_t )( ((int) hci_stack->substate) + 1);
1205 }
1206 
1207 // assumption: hci_can_send_command_packet_now() == true
1208 static void hci_initializing_run(void){
1209     log_debug("hci_initializing_run: substate %u, can send %u", hci_stack->substate, hci_can_send_command_packet_now());
1210     switch (hci_stack->substate){
1211         case HCI_INIT_SEND_RESET:
1212             hci_state_reset();
1213 
1214 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1215             // prepare reset if command complete not received in 100ms
1216             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1217             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1218             btstack_run_loop_add_timer(&hci_stack->timeout);
1219 #endif
1220             // send command
1221             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1222             hci_send_cmd(&hci_reset);
1223             break;
1224         case HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION:
1225             hci_send_cmd(&hci_read_local_version_information);
1226             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION;
1227             break;
1228         case HCI_INIT_SEND_READ_LOCAL_NAME:
1229             hci_send_cmd(&hci_read_local_name);
1230             hci_stack->substate = HCI_INIT_W4_SEND_READ_LOCAL_NAME;
1231             break;
1232 
1233 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1234         case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1235             hci_state_reset();
1236             // prepare reset if command complete not received in 100ms
1237             btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1238             btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1239             btstack_run_loop_add_timer(&hci_stack->timeout);
1240             // send command
1241             hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1242             hci_send_cmd(&hci_reset);
1243             break;
1244         case HCI_INIT_SEND_RESET_ST_WARM_BOOT:
1245             hci_state_reset();
1246             hci_stack->substate = HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT;
1247             hci_send_cmd(&hci_reset);
1248             break;
1249         case HCI_INIT_SEND_BAUD_CHANGE: {
1250             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1251             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1252             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1253             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1254             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1255             // STLC25000D: baudrate change happens within 0.5 s after command was send,
1256             // use timer to update baud rate after 100 ms (knowing exactly, when command was sent is non-trivial)
1257             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS){
1258                 btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1259                 btstack_run_loop_add_timer(&hci_stack->timeout);
1260             }
1261             break;
1262         }
1263         case HCI_INIT_SEND_BAUD_CHANGE_BCM: {
1264             uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1265             hci_stack->chipset->set_baudrate_command(baud_rate, hci_stack->hci_packet_buffer);
1266             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1267             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE_BCM;
1268             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1269             break;
1270         }
1271         case HCI_INIT_CUSTOM_INIT:
1272             // Custom initialization
1273             if (hci_stack->chipset && hci_stack->chipset->next_command){
1274                 hci_stack->chipset_result = (*hci_stack->chipset->next_command)(hci_stack->hci_packet_buffer);
1275                 int send_cmd = 0;
1276                 switch (hci_stack->chipset_result){
1277                     case BTSTACK_CHIPSET_VALID_COMMAND:
1278                         send_cmd = 1;
1279                         hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT;
1280                         break;
1281                     case BTSTACK_CHIPSET_WARMSTART_REQUIRED:
1282                         send_cmd = 1;
1283                         // CSR Warm Boot: Wait a bit, then send HCI Reset until HCI Command Complete
1284                         log_info("CSR Warm Boot");
1285                         btstack_run_loop_set_timer(&hci_stack->timeout, HCI_RESET_RESEND_TIMEOUT_MS);
1286                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1287                         btstack_run_loop_add_timer(&hci_stack->timeout);
1288                         if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO)
1289                             && hci_stack->config
1290                             && hci_stack->chipset
1291                             // && hci_stack->chipset->set_baudrate_command -- there's no such command
1292                             && hci_stack->hci_transport->set_baudrate
1293                             && hci_transport_uart_get_main_baud_rate()){
1294                             hci_stack->substate = HCI_INIT_W4_SEND_BAUD_CHANGE;
1295                         } else {
1296                            hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT_LINK_RESET;
1297                         }
1298                         break;
1299                     default:
1300                         break;
1301                 }
1302 
1303                 if (send_cmd){
1304                     int size = 3 + hci_stack->hci_packet_buffer[2];
1305                     hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1306                     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, hci_stack->hci_packet_buffer, size);
1307                     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1308                     break;
1309                 }
1310                 log_info("Init script done");
1311 
1312                 // Init script download on Broadcom chipsets causes:
1313                 if ( (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1314                    (  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION)
1315                 ||    (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA)) ){
1316 
1317                     // - baud rate to reset, restore UART baud rate if needed
1318                     int need_baud_change = hci_stack->config
1319                         && hci_stack->chipset
1320                         && hci_stack->chipset->set_baudrate_command
1321                         && hci_stack->hci_transport->set_baudrate
1322                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1323                     if (need_baud_change) {
1324                         uint32_t baud_rate = ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_init;
1325                         log_info("Local baud rate change to %"PRIu32" after init script (bcm)", baud_rate);
1326                         hci_stack->hci_transport->set_baudrate(baud_rate);
1327                     }
1328 
1329                     uint16_t bcm_delay_ms = 300;
1330                     // - UART may or may not be disabled during update and Controller RTS may or may not be high during this time
1331                     //   -> Work around: wait here.
1332                     log_info("BCM delay (%u ms) after init script", bcm_delay_ms);
1333                     hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_BCM_DELAY;
1334                     btstack_run_loop_set_timer(&hci_stack->timeout, bcm_delay_ms);
1335                     btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_initialization_timeout_handler);
1336                     btstack_run_loop_add_timer(&hci_stack->timeout);
1337                     break;
1338                 }
1339             }
1340             // otherwise continue
1341             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1342             hci_send_cmd(&hci_read_local_supported_commands);
1343             break;
1344         case HCI_INIT_SET_BD_ADDR:
1345             log_info("Set Public BD ADDR to %s", bd_addr_to_str(hci_stack->custom_bd_addr));
1346             hci_stack->chipset->set_bd_addr_command(hci_stack->custom_bd_addr, hci_stack->hci_packet_buffer);
1347             hci_stack->last_cmd_opcode = little_endian_read_16(hci_stack->hci_packet_buffer, 0);
1348             hci_stack->substate = HCI_INIT_W4_SET_BD_ADDR;
1349             hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1350             break;
1351 #endif
1352 
1353         case HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS:
1354             log_info("Resend hci_read_local_supported_commands after CSR Warm Boot double reset");
1355             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS;
1356             hci_send_cmd(&hci_read_local_supported_commands);
1357             break;
1358         case HCI_INIT_READ_BD_ADDR:
1359             hci_stack->substate = HCI_INIT_W4_READ_BD_ADDR;
1360             hci_send_cmd(&hci_read_bd_addr);
1361             break;
1362         case HCI_INIT_READ_BUFFER_SIZE:
1363             hci_stack->substate = HCI_INIT_W4_READ_BUFFER_SIZE;
1364             hci_send_cmd(&hci_read_buffer_size);
1365             break;
1366         case HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES:
1367             hci_stack->substate = HCI_INIT_W4_READ_LOCAL_SUPPORTED_FEATURES;
1368             hci_send_cmd(&hci_read_local_supported_features);
1369             break;
1370 
1371 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
1372         case HCI_INIT_SET_CONTROLLER_TO_HOST_FLOW_CONTROL:
1373             hci_stack->substate = HCI_INIT_W4_SET_CONTROLLER_TO_HOST_FLOW_CONTROL;
1374             hci_send_cmd(&hci_set_controller_to_host_flow_control, 3);  // ACL + SCO Flow Control
1375             break;
1376         case HCI_INIT_HOST_BUFFER_SIZE:
1377             hci_stack->substate = HCI_INIT_W4_HOST_BUFFER_SIZE;
1378             hci_send_cmd(&hci_host_buffer_size, HCI_HOST_ACL_PACKET_LEN, HCI_HOST_SCO_PACKET_LEN,
1379                                                 HCI_HOST_ACL_PACKET_NUM, HCI_HOST_SCO_PACKET_NUM);
1380             break;
1381 #endif
1382 
1383         case HCI_INIT_SET_EVENT_MASK:
1384             hci_stack->substate = HCI_INIT_W4_SET_EVENT_MASK;
1385             if (hci_le_supported()){
1386                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1387             } else {
1388                 // Kensington Bluetooth 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1389                 hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1390             }
1391             break;
1392 
1393 #ifdef ENABLE_CLASSIC
1394         case HCI_INIT_WRITE_SIMPLE_PAIRING_MODE:
1395             hci_stack->substate = HCI_INIT_W4_WRITE_SIMPLE_PAIRING_MODE;
1396             hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1397             break;
1398         case HCI_INIT_WRITE_PAGE_TIMEOUT:
1399             hci_stack->substate = HCI_INIT_W4_WRITE_PAGE_TIMEOUT;
1400             hci_send_cmd(&hci_write_page_timeout, 0x6000);  // ca. 15 sec
1401             break;
1402         case HCI_INIT_WRITE_DEFAULT_LINK_POLICY_SETTING:
1403             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_LINK_POLICY_SETTING;
1404             hci_send_cmd(&hci_write_default_link_policy_setting, hci_stack->default_link_policy_settings);
1405             break;
1406         case HCI_INIT_WRITE_CLASS_OF_DEVICE:
1407             hci_stack->substate = HCI_INIT_W4_WRITE_CLASS_OF_DEVICE;
1408             hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1409             break;
1410         case HCI_INIT_WRITE_LOCAL_NAME: {
1411             hci_stack->substate = HCI_INIT_W4_WRITE_LOCAL_NAME;
1412             hci_reserve_packet_buffer();
1413             uint8_t * packet = hci_stack->hci_packet_buffer;
1414             // construct HCI Command and send
1415             uint16_t opcode = hci_write_local_name.opcode;
1416             hci_stack->last_cmd_opcode = opcode;
1417             packet[0] = opcode & 0xff;
1418             packet[1] = opcode >> 8;
1419             packet[2] = DEVICE_NAME_LEN;
1420             memset(&packet[3], 0, DEVICE_NAME_LEN);
1421             uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1422             uint16_t bytes_to_copy = btstack_min(name_len, DEVICE_NAME_LEN);
1423             // if shorter than DEVICE_NAME_LEN, it's implicitly NULL-terminated by memset call
1424             (void)memcpy(&packet[3], hci_stack->local_name, bytes_to_copy);
1425             // expand '00:00:00:00:00:00' in name with bd_addr
1426             btstack_replace_bd_addr_placeholder(&packet[3], bytes_to_copy, hci_stack->local_bd_addr);
1427             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + DEVICE_NAME_LEN);
1428             break;
1429         }
1430         case HCI_INIT_WRITE_EIR_DATA: {
1431             hci_stack->substate = HCI_INIT_W4_WRITE_EIR_DATA;
1432             hci_reserve_packet_buffer();
1433             uint8_t * packet = hci_stack->hci_packet_buffer;
1434             // construct HCI Command in-place and send
1435             uint16_t opcode = hci_write_extended_inquiry_response.opcode;
1436             hci_stack->last_cmd_opcode = opcode;
1437             uint16_t offset = 0;
1438             packet[offset++] = opcode & 0xff;
1439             packet[offset++] = opcode >> 8;
1440             packet[offset++] = 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN;
1441             packet[offset++] = 0;  // FEC not required
1442             memset(&packet[offset], 0, EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1443             if (hci_stack->eir_data){
1444                 // copy items and expand '00:00:00:00:00:00' in name with bd_addr
1445                 ad_context_t context;
1446                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, hci_stack->eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)) {
1447                     uint8_t data_type   = ad_iterator_get_data_type(&context);
1448                     uint8_t size        = ad_iterator_get_data_len(&context);
1449                     const uint8_t *data = ad_iterator_get_data(&context);
1450                     // copy item
1451                     packet[offset++] = size + 1;
1452                     packet[offset++] = data_type;
1453                     memcpy(&packet[offset], data, size);
1454                     // update name item
1455                     if ((data_type == BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME) || (data_type == BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME)){
1456                         btstack_replace_bd_addr_placeholder(&packet[offset], size, hci_stack->local_bd_addr);
1457                     }
1458                     offset += size;
1459                 }
1460             } else {
1461                 uint16_t name_len = (uint16_t) strlen(hci_stack->local_name);
1462                 uint16_t bytes_to_copy = btstack_min(name_len, EXTENDED_INQUIRY_RESPONSE_DATA_LEN - 2);
1463                 packet[offset++] = bytes_to_copy + 1;
1464                 packet[offset++] = BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME;
1465                 (void)memcpy(&packet[6], hci_stack->local_name, bytes_to_copy);
1466                 // expand '00:00:00:00:00:00' in name with bd_addr
1467                 btstack_replace_bd_addr_placeholder(&packet[offset], bytes_to_copy, hci_stack->local_bd_addr);
1468             }
1469             hci_send_cmd_packet(packet, HCI_CMD_HEADER_SIZE + 1 + EXTENDED_INQUIRY_RESPONSE_DATA_LEN);
1470             break;
1471         }
1472         case HCI_INIT_WRITE_INQUIRY_MODE:
1473             hci_stack->substate = HCI_INIT_W4_WRITE_INQUIRY_MODE;
1474             hci_send_cmd(&hci_write_inquiry_mode, (int) hci_stack->inquiry_mode);
1475             break;
1476         case HCI_INIT_WRITE_SECURE_CONNECTIONS_HOST_ENABLE:
1477             hci_send_cmd(&hci_write_secure_connections_host_support, 1);
1478             hci_stack->substate = HCI_INIT_W4_WRITE_SECURE_CONNECTIONS_HOST_ENABLE;
1479             break;
1480         case HCI_INIT_WRITE_SCAN_ENABLE:
1481             hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1482             hci_stack->substate = HCI_INIT_W4_WRITE_SCAN_ENABLE;
1483             break;
1484         // only sent if ENABLE_SCO_OVER_HCI is defined
1485         case HCI_INIT_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1486             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1487             hci_send_cmd(&hci_write_synchronous_flow_control_enable, 1); // SCO tracking enabled
1488             break;
1489         case HCI_INIT_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1490             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1491             hci_send_cmd(&hci_write_default_erroneous_data_reporting, 1);
1492             break;
1493         // only sent if ENABLE_SCO_OVER_HCI and manufacturer is Broadcom
1494         case HCI_INIT_BCM_WRITE_SCO_PCM_INT:
1495             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1496             log_info("BCM: Route SCO data via HCI transport");
1497             hci_send_cmd(&hci_bcm_write_sco_pcm_int, 1, 0, 0, 0, 0);
1498             break;
1499 
1500 #endif
1501 #ifdef ENABLE_BLE
1502         // LE INIT
1503         case HCI_INIT_LE_READ_BUFFER_SIZE:
1504             hci_stack->substate = HCI_INIT_W4_LE_READ_BUFFER_SIZE;
1505             hci_send_cmd(&hci_le_read_buffer_size);
1506             break;
1507         case HCI_INIT_LE_SET_EVENT_MASK:
1508             hci_stack->substate = HCI_INIT_W4_LE_SET_EVENT_MASK;
1509             hci_send_cmd(&hci_le_set_event_mask, 0x809FF, 0x0); // bits 0-8, 11, 19
1510             break;
1511         case HCI_INIT_WRITE_LE_HOST_SUPPORTED:
1512             // LE Supported Host = 1, Simultaneous Host = 0
1513             hci_stack->substate = HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED;
1514             hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1515             break;
1516 #endif
1517 
1518 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1519         case HCI_INIT_LE_READ_MAX_DATA_LENGTH:
1520             hci_stack->substate = HCI_INIT_W4_LE_READ_MAX_DATA_LENGTH;
1521             hci_send_cmd(&hci_le_read_maximum_data_length);
1522             break;
1523         case HCI_INIT_LE_WRITE_SUGGESTED_DATA_LENGTH:
1524             hci_stack->substate = HCI_INIT_W4_LE_WRITE_SUGGESTED_DATA_LENGTH;
1525             hci_send_cmd(&hci_le_write_suggested_default_data_length, hci_stack->le_supported_max_tx_octets, hci_stack->le_supported_max_tx_time);
1526             break;
1527 #endif
1528 
1529 #ifdef ENABLE_LE_CENTRAL
1530         case HCI_INIT_READ_WHITE_LIST_SIZE:
1531             hci_stack->substate = HCI_INIT_W4_READ_WHITE_LIST_SIZE;
1532             hci_send_cmd(&hci_le_read_white_list_size);
1533             break;
1534         case HCI_INIT_LE_SET_SCAN_PARAMETERS:
1535             // LE Scan Parameters: active scanning, 300 ms interval, 30 ms window, own address type, accept all advs
1536             hci_stack->substate = HCI_INIT_W4_LE_SET_SCAN_PARAMETERS;
1537             hci_send_cmd(&hci_le_set_scan_parameters, 1, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
1538             break;
1539 #endif
1540         default:
1541             return;
1542     }
1543 }
1544 
1545 static void hci_init_done(void){
1546     // done. tell the app
1547     log_info("hci_init_done -> HCI_STATE_WORKING");
1548     hci_stack->state = HCI_STATE_WORKING;
1549     hci_emit_state();
1550     hci_run();
1551 }
1552 
1553 static bool hci_initializing_event_handler_command_completed(const uint8_t * packet){
1554     bool command_completed = false;
1555     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE){
1556         uint16_t opcode = little_endian_read_16(packet,3);
1557         if (opcode == hci_stack->last_cmd_opcode){
1558             command_completed = true;
1559             log_debug("Command complete for expected opcode %04x at substate %u", opcode, hci_stack->substate);
1560         } else {
1561             log_info("Command complete for different opcode %04x, expected %04x, at substate %u", opcode, hci_stack->last_cmd_opcode, hci_stack->substate);
1562         }
1563     }
1564 
1565     if (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_STATUS){
1566         uint8_t  status = packet[2];
1567         uint16_t opcode = little_endian_read_16(packet,4);
1568         if (opcode == hci_stack->last_cmd_opcode){
1569             if (status){
1570                 command_completed = true;
1571                 log_debug("Command status error 0x%02x for expected opcode %04x at substate %u", status, opcode, hci_stack->substate);
1572             } else {
1573                 log_info("Command status OK for expected opcode %04x, waiting for command complete", opcode);
1574             }
1575         } else {
1576             log_debug("Command status for opcode %04x, expected %04x", opcode, hci_stack->last_cmd_opcode);
1577         }
1578     }
1579 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1580     // Vendor == CSR
1581     if ((hci_stack->substate == HCI_INIT_W4_CUSTOM_INIT) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1582         // TODO: track actual command
1583         command_completed = true;
1584     }
1585 
1586     // Vendor == Toshiba
1587     if ((hci_stack->substate == HCI_INIT_W4_SEND_BAUD_CHANGE) && (hci_event_packet_get_type(packet) == HCI_EVENT_VENDOR_SPECIFIC)){
1588         // TODO: track actual command
1589         command_completed = true;
1590         // Fix: no HCI Command Complete received, so num_cmd_packets not reset
1591         hci_stack->num_cmd_packets = 1;
1592     }
1593 #endif
1594 
1595     return command_completed;
1596 }
1597 
1598 static void hci_initializing_event_handler(const uint8_t * packet, uint16_t size){
1599 
1600     UNUSED(size);   // ok: less than 6 bytes are read from our buffer
1601 
1602     bool command_completed =  hci_initializing_event_handler_command_completed(packet);
1603 
1604 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1605 
1606     // Late response (> 100 ms) for HCI Reset e.g. on Toshiba TC35661:
1607     // Command complete for HCI Reset arrives after we've resent the HCI Reset command
1608     //
1609     // HCI Reset
1610     // Timeout 100 ms
1611     // HCI Reset
1612     // Command Complete Reset
1613     // HCI Read Local Version Information
1614     // Command Complete Reset - but we expected Command Complete Read Local Version Information
1615     // hang...
1616     //
1617     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1618     if (!command_completed
1619             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1620             && (hci_stack->substate == HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION)){
1621 
1622         uint16_t opcode = little_endian_read_16(packet,3);
1623         if (opcode == hci_reset.opcode){
1624             hci_stack->substate = HCI_INIT_SEND_READ_LOCAL_VERSION_INFORMATION;
1625             return;
1626         }
1627     }
1628 
1629     // CSR & H5
1630     // Fix: Command Complete for HCI Reset in HCI_INIT_W4_SEND_READ_LOCAL_VERSION_INFORMATION trigger resend
1631     if (!command_completed
1632             && (hci_event_packet_get_type(packet) == HCI_EVENT_COMMAND_COMPLETE)
1633             && (hci_stack->substate == HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS)){
1634 
1635         uint16_t opcode = little_endian_read_16(packet,3);
1636         if (opcode == hci_reset.opcode){
1637             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1638             return;
1639         }
1640     }
1641 
1642     // on CSR with BCSP/H5, the reset resend timeout leads to substate == HCI_INIT_SEND_RESET or HCI_INIT_SEND_RESET_CSR_WARM_BOOT
1643     // fix: Correct substate and behave as command below
1644     if (command_completed){
1645         switch (hci_stack->substate){
1646             case HCI_INIT_SEND_RESET:
1647                 hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1648                 break;
1649             case HCI_INIT_SEND_RESET_CSR_WARM_BOOT:
1650                 hci_stack->substate = HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT;
1651                 break;
1652             default:
1653                 break;
1654         }
1655     }
1656 
1657 #endif
1658 
1659     if (!command_completed) return;
1660 
1661     bool need_baud_change = false;
1662     bool need_addr_change = false;
1663 
1664 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1665     need_baud_change = hci_stack->config
1666                         && hci_stack->chipset
1667                         && hci_stack->chipset->set_baudrate_command
1668                         && hci_stack->hci_transport->set_baudrate
1669                         && ((hci_transport_config_uart_t *)hci_stack->config)->baudrate_main;
1670 
1671     need_addr_change = hci_stack->custom_bd_addr_set
1672                         && hci_stack->chipset
1673                         && hci_stack->chipset->set_bd_addr_command;
1674 #endif
1675 
1676     switch(hci_stack->substate){
1677 
1678 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1679         case HCI_INIT_SEND_RESET:
1680             // on CSR with BCSP/H5, resend triggers resend of HCI Reset and leads to substate == HCI_INIT_SEND_RESET
1681             // fix: just correct substate and behave as command below
1682             hci_stack->substate = HCI_INIT_W4_SEND_RESET;
1683             btstack_run_loop_remove_timer(&hci_stack->timeout);
1684             break;
1685         case HCI_INIT_W4_SEND_RESET:
1686             btstack_run_loop_remove_timer(&hci_stack->timeout);
1687             break;
1688         case HCI_INIT_W4_SEND_READ_LOCAL_NAME:
1689             log_info("Received local name, need baud change %d", (int) need_baud_change);
1690             if (need_baud_change){
1691                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE;
1692                 return;
1693             }
1694             // skip baud change
1695             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1696             return;
1697         case HCI_INIT_W4_SEND_BAUD_CHANGE:
1698             // for STLC2500D, baud rate change already happened.
1699             // for others, baud rate gets changed now
1700             if ((hci_stack->manufacturer != BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS) && need_baud_change){
1701                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1702                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change)", baud_rate);
1703                 hci_stack->hci_transport->set_baudrate(baud_rate);
1704             }
1705             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1706             return;
1707         case HCI_INIT_W4_CUSTOM_INIT_CSR_WARM_BOOT:
1708             btstack_run_loop_remove_timer(&hci_stack->timeout);
1709             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1710             return;
1711         case HCI_INIT_W4_CUSTOM_INIT:
1712             // repeat custom init
1713             hci_stack->substate = HCI_INIT_CUSTOM_INIT;
1714             return;
1715 #else
1716         case HCI_INIT_W4_SEND_RESET:
1717             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_COMMANDS;
1718             return ;
1719 #endif
1720 
1721         case HCI_INIT_W4_READ_LOCAL_SUPPORTED_COMMANDS:
1722             if (need_baud_change && (hci_stack->chipset_result != BTSTACK_CHIPSET_NO_INIT_SCRIPT) &&
1723               ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) ||
1724                (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_EM_MICROELECTRONIC_MARIN_SA))) {
1725                 hci_stack->substate = HCI_INIT_SEND_BAUD_CHANGE_BCM;
1726                 return;
1727             }
1728             if (need_addr_change){
1729                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1730                 return;
1731             }
1732             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1733             return;
1734 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
1735         case HCI_INIT_W4_SEND_BAUD_CHANGE_BCM:
1736             if (need_baud_change){
1737                 uint32_t baud_rate = hci_transport_uart_get_main_baud_rate();
1738                 log_info("Local baud rate change to %"PRIu32"(w4_send_baud_change_bcm))", baud_rate);
1739                 hci_stack->hci_transport->set_baudrate(baud_rate);
1740             }
1741             if (need_addr_change){
1742                 hci_stack->substate = HCI_INIT_SET_BD_ADDR;
1743                 return;
1744             }
1745             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1746             return;
1747         case HCI_INIT_W4_SET_BD_ADDR:
1748             // for STLC2500D + ATWILC3000, bd addr change only gets active after sending reset command
1749             if ((hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ST_MICROELECTRONICS)
1750             ||  (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_ATMEL_CORPORATION)){
1751                 hci_stack->substate = HCI_INIT_SEND_RESET_ST_WARM_BOOT;
1752                 return;
1753             }
1754             // skipping st warm boot
1755             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1756             return;
1757         case HCI_INIT_W4_SEND_RESET_ST_WARM_BOOT:
1758             hci_stack->substate = HCI_INIT_READ_BD_ADDR;
1759             return;
1760 #endif
1761         case HCI_INIT_W4_READ_BD_ADDR:
1762             // only read buffer size if supported
1763             if (hci_stack->local_supported_commands[0] & 0x01) {
1764                 hci_stack->substate = HCI_INIT_READ_BUFFER_SIZE;
1765                 return;
1766             }
1767             // skipping read buffer size
1768             hci_stack->substate = HCI_INIT_READ_LOCAL_SUPPORTED_FEATURES;
1769             return;
1770         case HCI_INIT_W4_SET_EVENT_MASK:
1771             // skip Classic init commands for LE only chipsets
1772             if (!hci_classic_supported()){
1773 #ifdef ENABLE_BLE
1774                 if (hci_le_supported()){
1775                     hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE; // skip all classic command
1776                     return;
1777                 }
1778 #endif
1779                 log_error("Neither BR/EDR nor LE supported");
1780                 hci_init_done();
1781                 return;
1782             }
1783             if (!gap_ssp_supported()){
1784                 hci_stack->substate = HCI_INIT_WRITE_PAGE_TIMEOUT;
1785                 return;
1786             }
1787             break;
1788 #ifdef ENABLE_BLE
1789         case HCI_INIT_W4_LE_READ_BUFFER_SIZE:
1790             // skip write le host if not supported (e.g. on LE only EM9301)
1791             if (hci_stack->local_supported_commands[0] & 0x02) break;
1792             hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1793             return;
1794 
1795 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1796         case HCI_INIT_W4_WRITE_LE_HOST_SUPPORTED:
1797             log_info("Supported commands %x", hci_stack->local_supported_commands[0] & 0x30);
1798             if ((hci_stack->local_supported_commands[0] & 0x30) == 0x30){
1799                 hci_stack->substate = HCI_INIT_LE_SET_EVENT_MASK;
1800                 return;
1801             }
1802             // explicit fall through to reduce repetitions
1803 
1804 #ifdef ENABLE_LE_CENTRAL
1805             hci_stack->substate = HCI_INIT_READ_WHITE_LIST_SIZE;
1806 #else
1807             hci_init_done();
1808 #endif
1809             return;
1810 #endif  /* ENABLE_LE_DATA_LENGTH_EXTENSION */
1811 
1812 #endif  /* ENABLE_BLE */
1813 
1814         case HCI_INIT_W4_WRITE_INQUIRY_MODE:
1815             // skip write secure connections host support if not supported or disabled
1816             if (hci_stack->secure_connections_enable && hci_stack->local_supported_commands[1] & 0x02) {
1817                 hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;
1818                 return;
1819             }
1820             break;
1821 
1822 #ifdef ENABLE_SCO_OVER_HCI
1823         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1824             // skip write synchronous flow control if not supported
1825             if (hci_stack->local_supported_commands[0] & 0x04) break;
1826             hci_stack->substate = HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE;
1827 
1828             /* fall through */
1829 
1830         case HCI_INIT_W4_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
1831             // skip write default erroneous data reporting if not supported
1832             if (hci_stack->local_supported_commands[0] & 0x08) break;
1833             hci_stack->substate = HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING;
1834 
1835             /* fall through */
1836 
1837         case HCI_INIT_W4_WRITE_DEFAULT_ERRONEOUS_DATA_REPORTING:
1838             // skip bcm set sco pcm config on non-Broadcom chipsets
1839             if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION) break;
1840             hci_stack->substate = HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT;
1841 
1842             /* fall through */
1843 
1844         case HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT:
1845             if (!hci_le_supported()){
1846                 // SKIP LE init for Classic only configuration
1847                 hci_init_done();
1848                 return;
1849             }
1850             break;
1851 
1852 #else /* !ENABLE_SCO_OVER_HCI */
1853 
1854         case HCI_INIT_W4_WRITE_SCAN_ENABLE:
1855 #ifdef ENABLE_BLE
1856             if (hci_le_supported()){
1857                 hci_stack->substate = HCI_INIT_LE_READ_BUFFER_SIZE;
1858                 return;
1859             }
1860 #endif
1861             // SKIP LE init for Classic only configuration
1862             hci_init_done();
1863             return;
1864 #endif /* ENABLE_SCO_OVER_HCI */
1865 
1866 // avoid compile error due to duplicate cases: HCI_INIT_W4_BCM_WRITE_SCO_PCM_INT == HCI_INIT_DONE-1
1867 #if defined(ENABLE_BLE) || defined(ENABLE_LE_DATA_LENGTH_EXTENSION) || defined(ENABLE_LE_CENTRAL)
1868         // Response to command before init done state -> init done
1869         case (HCI_INIT_DONE-1):
1870             hci_init_done();
1871             return;
1872 #endif
1873 
1874         default:
1875             break;
1876     }
1877     hci_initializing_next_state();
1878 }
1879 
1880 static void hci_handle_connection_failed(hci_connection_t * conn, uint8_t status){
1881     log_info("Outgoing connection to %s failed", bd_addr_to_str(conn->address));
1882     bd_addr_t bd_address;
1883     (void)memcpy(&bd_address, conn->address, 6);
1884 
1885 #ifdef ENABLE_CLASSIC
1886     // cache needed data
1887     int notify_dedicated_bonding_failed = conn->bonding_flags & BONDING_DEDICATED;
1888 #endif
1889 
1890     // connection failed, remove entry
1891     btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
1892     btstack_memory_hci_connection_free( conn );
1893 
1894 #ifdef ENABLE_CLASSIC
1895     // notify client if dedicated bonding
1896     if (notify_dedicated_bonding_failed){
1897         log_info("hci notify_dedicated_bonding_failed");
1898         hci_emit_dedicated_bonding_result(bd_address, status);
1899     }
1900 
1901     // if authentication error, also delete link key
1902     if (status == ERROR_CODE_AUTHENTICATION_FAILURE) {
1903         gap_drop_link_key_for_bd_addr(bd_address);
1904     }
1905 #endif
1906 }
1907 
1908 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1909     // handle BT initialization
1910     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1911         hci_initializing_event_handler(packet, size);
1912     }
1913 
1914     // help with BT sleep
1915     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1916         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1917         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1918         hci_initializing_next_state();
1919     }
1920 }
1921 
1922 static void event_handler(uint8_t *packet, int size){
1923 
1924     uint16_t event_length = packet[1];
1925 
1926     // assert packet is complete
1927     if (size != (event_length + 2)){
1928         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
1929         return;
1930     }
1931 
1932     bd_addr_t addr;
1933     bd_addr_type_t addr_type;
1934     hci_con_handle_t handle;
1935     hci_connection_t * conn;
1936     int i;
1937     int create_connection_cmd;
1938 
1939 #ifdef ENABLE_CLASSIC
1940     uint8_t link_type;
1941 #endif
1942 
1943     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
1944 
1945     switch (hci_event_packet_get_type(packet)) {
1946 
1947         case HCI_EVENT_COMMAND_COMPLETE:
1948             // get num cmd packets - limit to 1 to reduce complexity
1949             hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1950 
1951             if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_name)){
1952                 if (packet[5]) break;
1953                 // terminate, name 248 chars
1954                 packet[6+248] = 0;
1955                 log_info("local name: %s", &packet[6]);
1956             }
1957             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_buffer_size)){
1958                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
1959                 if (hci_stack->state == HCI_STATE_INITIALIZING){
1960                     uint16_t acl_len = little_endian_read_16(packet, 6);
1961                     uint16_t sco_len = packet[8];
1962 
1963                     // determine usable ACL/SCO payload size
1964                     hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
1965                     hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
1966 
1967                     hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
1968                     hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
1969 
1970                     log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
1971                              acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
1972                              hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
1973                 }
1974             }
1975             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_rssi)){
1976                 if (packet[5] == 0){
1977                     uint8_t event[5];
1978                     event[0] = GAP_EVENT_RSSI_MEASUREMENT;
1979                     event[1] = 3;
1980                     (void)memcpy(&event[2], &packet[6], 3);
1981                     hci_emit_event(event, sizeof(event), 1);
1982                 }
1983             }
1984 #ifdef ENABLE_BLE
1985             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_buffer_size)){
1986                 hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
1987                 hci_stack->le_acl_packets_total_num  = packet[8];
1988                 // determine usable ACL payload size
1989                 if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
1990                     hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
1991                 }
1992                 log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
1993             }
1994 #endif
1995 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
1996             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_maximum_data_length)){
1997                 hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
1998                 hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
1999                 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);
2000             }
2001 #endif
2002 #ifdef ENABLE_LE_CENTRAL
2003             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_le_read_white_list_size)){
2004                 hci_stack->le_whitelist_capacity = packet[6];
2005                 log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2006             }
2007 #endif
2008             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_bd_addr)) {
2009                 reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2010 				hci_stack->local_bd_addr);
2011                 log_info("Local Address, Status: 0x%02x: Addr: %s",
2012                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2013 #ifdef ENABLE_CLASSIC
2014                 if (hci_stack->link_key_db){
2015                     hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2016                 }
2017 #endif
2018             }
2019 #ifdef ENABLE_CLASSIC
2020             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)){
2021                 hci_emit_discoverable_enabled(hci_stack->discoverable);
2022             }
2023             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_inquiry_cancel)){
2024                 if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2025                     hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2026                     uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2027                     hci_emit_event(event, sizeof(event), 1);
2028                 }
2029             }
2030 #endif
2031 
2032             // Note: HCI init checks
2033             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_features)){
2034                 (void)memcpy(hci_stack->local_supported_features,
2035 			     &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1],
2036 			     8);
2037 
2038 #ifdef ENABLE_CLASSIC
2039                 // determine usable ACL packet types based on host buffer size and supported features
2040                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2041                 log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2042 #endif
2043                 // Classic/LE
2044                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2045             }
2046             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_version_information)){
2047                 // hci_stack->hci_version    = little_endian_read_16(packet, 4);
2048                 // hci_stack->hci_revision   = little_endian_read_16(packet, 6);
2049                 uint16_t manufacturer = little_endian_read_16(packet, 10);
2050                 // map Cypress to Broadcom
2051                 if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2052                     log_info("Treat Cypress as Broadcom");
2053                     manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2054                     little_endian_store_16(packet, 10, manufacturer);
2055                 }
2056                 hci_stack->manufacturer = manufacturer;
2057                 // hci_stack->lmp_version    = little_endian_read_16(packet, 8);
2058                 // hci_stack->lmp_subversion = little_endian_read_16(packet, 12);
2059                 log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2060             }
2061             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_local_supported_commands)){
2062                 hci_stack->local_supported_commands[0] =
2063                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2064                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2065                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2066                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2067                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2068                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2069                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2070                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2071                 hci_stack->local_supported_commands[1] =
2072                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+ 2] & 0x40) >> 6) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2073                     ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+32] & 0x08) >> 2);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2074                 log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2075             }
2076 #ifdef ENABLE_CLASSIC
2077             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_synchronous_flow_control_enable)){
2078                 if (packet[5] == 0){
2079                     hci_stack->synchronous_flow_control_enabled = 1;
2080                 }
2081             }
2082             else if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_read_encryption_key_size)){
2083                 uint8_t status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2084                 handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2085                 conn   = hci_connection_for_handle(handle);
2086                 if (!conn) break;
2087                 if (status == 0){
2088                     uint8_t key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2089                     log_info("Handle %x04x key Size: %u", handle, key_size);
2090                     conn->encryption_key_size = key_size;
2091                 } else {
2092                     log_info("Read Encryption Key Size failed -> assuming insecure connection with key size of 1");
2093                     conn->encryption_key_size = 1;
2094                 }
2095                 conn->authentication_flags |= CONNECTION_ENCRYPTED;
2096                 hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2097             }
2098 #endif
2099             break;
2100 
2101         case HCI_EVENT_COMMAND_STATUS:
2102             // get num cmd packets - limit to 1 to reduce complexity
2103             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2104 
2105             // check command status to detected failed outgoing connections
2106             create_connection_cmd = 0;
2107 #ifdef ENABLE_CLASSIC
2108             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2109                 create_connection_cmd = 1;
2110             }
2111 #endif
2112 #ifdef ENABLE_LE_CENTRAL
2113             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2114                 create_connection_cmd = 1;
2115             }
2116 #endif
2117             if (create_connection_cmd) {
2118                 uint8_t status = hci_event_command_status_get_status(packet);
2119                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2120                 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);
2121 
2122                 // reset outgoing address info
2123                 memset(hci_stack->outgoing_addr, 0, 6);
2124                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2125 
2126                 // error => outgoing connection failed
2127                 if ((conn != NULL) && (status != 0)){
2128                     hci_handle_connection_failed(conn, status);
2129                 }
2130             }
2131             break;
2132 
2133         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2134             if (size < 3) return;
2135             uint16_t num_handles = packet[2];
2136             if (size != (3 + num_handles * 4)) return;
2137             uint16_t offset = 3;
2138             for (i=0; i<num_handles;i++){
2139                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2140                 offset += 2;
2141                 uint16_t num_packets = little_endian_read_16(packet, offset);
2142                 offset += 2;
2143 
2144                 conn = hci_connection_for_handle(handle);
2145                 if (!conn){
2146                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2147                     continue;
2148                 }
2149 
2150                 if (conn->num_packets_sent >= num_packets){
2151                     conn->num_packets_sent -= num_packets;
2152                 } else {
2153                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2154                     conn->num_packets_sent = 0;
2155                 }
2156                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2157 
2158 #ifdef ENABLE_CLASSIC
2159                 // For SCO, we do the can_send_now_check here
2160                 hci_notify_if_sco_can_send_now();
2161 #endif
2162             }
2163             break;
2164         }
2165 
2166 #ifdef ENABLE_CLASSIC
2167         case HCI_EVENT_INQUIRY_COMPLETE:
2168             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2169                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2170                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2171                 hci_emit_event(event, sizeof(event), 1);
2172             }
2173             break;
2174         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2175             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2176                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2177             }
2178             break;
2179         case HCI_EVENT_CONNECTION_REQUEST:
2180             reverse_bd_addr(&packet[2], addr);
2181             if (hci_stack->gap_classic_accept_callback != NULL){
2182                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2183                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2184                     bd_addr_copy(hci_stack->decline_addr, addr);
2185                     break;
2186                 }
2187             }
2188 
2189             // TODO: eval COD 8-10
2190             link_type = packet[11];
2191             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2192             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2193             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2194             if (!conn) {
2195                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2196             }
2197             if (!conn) {
2198                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2199                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2200                 bd_addr_copy(hci_stack->decline_addr, addr);
2201                 break;
2202             }
2203             conn->role  = HCI_ROLE_SLAVE;
2204             conn->state = RECEIVED_CONNECTION_REQUEST;
2205             // store info about eSCO
2206             if (link_type == 0x02){
2207                 conn->remote_supported_feature_eSCO = 1;
2208             }
2209             hci_run();
2210             break;
2211 
2212         case HCI_EVENT_CONNECTION_COMPLETE:
2213             // Connection management
2214             reverse_bd_addr(&packet[5], addr);
2215             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2216             addr_type = BD_ADDR_TYPE_ACL;
2217             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2218             if (conn) {
2219                 if (!packet[2]){
2220                     conn->state = OPEN;
2221                     conn->con_handle = little_endian_read_16(packet, 3);
2222 
2223                     // queue get remote feature
2224                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
2225 
2226                     // queue set supervision timeout if we're master
2227                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2228                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2229                     }
2230 
2231                     // restart timer
2232                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2233                     btstack_run_loop_add_timer(&conn->timeout);
2234 
2235                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2236 
2237                     hci_emit_nr_connections_changed();
2238                 } else {
2239                     // connection failed
2240                     hci_handle_connection_failed(conn, packet[2]);
2241                 }
2242             }
2243             break;
2244 
2245         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2246             reverse_bd_addr(&packet[5], addr);
2247             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2248             if (packet[2]){
2249                 // connection failed
2250                 break;
2251             }
2252             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2253             if (!conn) {
2254                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2255             }
2256             if (!conn) {
2257                 break;
2258             }
2259             conn->state = OPEN;
2260             conn->con_handle = little_endian_read_16(packet, 3);
2261 
2262 #ifdef ENABLE_SCO_OVER_HCI
2263             // update SCO
2264             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2265                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2266             }
2267             // trigger can send now
2268             if (hci_have_usb_transport()){
2269                 hci_stack->sco_can_send_now = 1;
2270             }
2271 #endif
2272             break;
2273 
2274         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2275             handle = little_endian_read_16(packet, 3);
2276             conn = hci_connection_for_handle(handle);
2277             if (!conn) break;
2278             if (!packet[2]){
2279                 uint8_t * features = &packet[5];
2280                 if (features[6] & (1 << 3)){
2281                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
2282                 }
2283                 if (features[3] & (1<<7)){
2284                     conn->remote_supported_feature_eSCO = 1;
2285                 }
2286             }
2287             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
2288             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x, eSCO %u", conn->bonding_flags, conn->remote_supported_feature_eSCO);
2289             if (conn->bonding_flags & BONDING_DEDICATED){
2290                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2291             }
2292             break;
2293 
2294         case HCI_EVENT_LINK_KEY_REQUEST:
2295             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2296             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2297             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2298             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2299             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2300             hci_run();
2301             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2302             return;
2303 
2304         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2305             reverse_bd_addr(&packet[2], addr);
2306             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2307             if (!conn) break;
2308             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2309             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2310             // Change Connection Encryption keeps link key type
2311             if (link_key_type != CHANGED_COMBINATION_KEY){
2312                 conn->link_key_type = link_key_type;
2313             }
2314             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2315             // still forward event to allow dismiss of pairing dialog
2316             break;
2317         }
2318 
2319         case HCI_EVENT_PIN_CODE_REQUEST:
2320             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2321             // non-bondable mode: pin code negative reply will be sent
2322             if (!hci_stack->bondable){
2323                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2324                 hci_run();
2325                 return;
2326             }
2327             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2328             if (!hci_stack->link_key_db) break;
2329             hci_event_pin_code_request_get_bd_addr(packet, addr);
2330             hci_stack->link_key_db->delete_link_key(addr);
2331             break;
2332 
2333         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2334             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2335             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2336             break;
2337 
2338         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2339             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2340             if (!hci_stack->ssp_auto_accept) break;
2341             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2342             break;
2343 
2344         case HCI_EVENT_USER_PASSKEY_REQUEST:
2345             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2346             if (!hci_stack->ssp_auto_accept) break;
2347             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2348             break;
2349         case HCI_EVENT_MODE_CHANGE:
2350             handle = hci_event_mode_change_get_handle(packet);
2351             conn = hci_connection_for_handle(handle);
2352             if (!conn) break;
2353             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2354             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2355             break;
2356 #endif
2357 
2358         case HCI_EVENT_ENCRYPTION_CHANGE:
2359             handle = little_endian_read_16(packet, 3);
2360             conn = hci_connection_for_handle(handle);
2361             if (!conn) break;
2362             if (packet[2] == 0) {
2363                 if (packet[5]){
2364                     if (hci_is_le_connection(conn)){
2365                         // For LE, we accept connection as encrypted
2366                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2367                     }
2368 #ifdef ENABLE_CLASSIC
2369                     else {
2370                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2371                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2372                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2373                         } else {
2374                             // if not, pretend everything is perfect
2375                             conn->encryption_key_size = 16;
2376                             conn->authentication_flags |= CONNECTION_ENCRYPTED;
2377                             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2378                         }
2379                     }
2380 #endif
2381                 } else {
2382                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2383                 }
2384             }
2385 
2386             break;
2387 
2388 #ifdef ENABLE_CLASSIC
2389         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2390             handle = little_endian_read_16(packet, 3);
2391             conn = hci_connection_for_handle(handle);
2392             if (!conn) break;
2393 
2394             // dedicated bonding: send result and disconnect
2395             if (conn->bonding_flags & BONDING_DEDICATED){
2396                 conn->bonding_flags &= ~BONDING_DEDICATED;
2397                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2398                 conn->bonding_status = packet[2];
2399                 break;
2400             }
2401 
2402             if ((packet[2] == 0) && (gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)){
2403                 // link key sufficient for requested security
2404                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2405                 break;
2406             }
2407             // not enough
2408             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2409             break;
2410 #endif
2411 
2412         // HCI_EVENT_DISCONNECTION_COMPLETE
2413         // has been split, to first notify stack before shutting connection down
2414         // see end of function, too.
2415         case HCI_EVENT_DISCONNECTION_COMPLETE:
2416             if (packet[2]) break;   // status != 0
2417             handle = little_endian_read_16(packet, 3);
2418             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2419             if (hci_stack->acl_fragmentation_total_size > 0) {
2420                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2421                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2422                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2423                     hci_stack->acl_fragmentation_total_size = 0;
2424                     hci_stack->acl_fragmentation_pos = 0;
2425                     if (release_buffer){
2426                         hci_release_packet_buffer();
2427                     }
2428                 }
2429             }
2430 
2431             conn = hci_connection_for_handle(handle);
2432             if (!conn) break;
2433             // mark connection for shutdown
2434             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2435 
2436             // emit dedicatd bonding event
2437             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2438                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2439             }
2440 
2441 #ifdef ENABLE_BLE
2442 #ifdef ENABLE_LE_PERIPHERAL
2443             // re-enable advertisements for le connections if active
2444             if (hci_is_le_connection(conn)){
2445                 hci_reenable_advertisements_if_needed();
2446             }
2447 #endif
2448 #endif
2449             break;
2450 
2451         case HCI_EVENT_HARDWARE_ERROR:
2452             log_error("Hardware Error: 0x%02x", packet[2]);
2453             if (hci_stack->hardware_error_callback){
2454                 (*hci_stack->hardware_error_callback)(packet[2]);
2455             } else {
2456                 // if no special requests, just reboot stack
2457                 hci_power_control_off();
2458                 hci_power_control_on();
2459             }
2460             break;
2461 
2462 #ifdef ENABLE_CLASSIC
2463         case HCI_EVENT_ROLE_CHANGE:
2464             if (packet[2]) break;   // status != 0
2465             reverse_bd_addr(&packet[3], addr);
2466             addr_type = BD_ADDR_TYPE_ACL;
2467             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2468             if (!conn) break;
2469             conn->role = packet[9];
2470             break;
2471 #endif
2472 
2473         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2474             // release packet buffer only for asynchronous transport and if there are not further fragements
2475             if (hci_transport_synchronous()) {
2476                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2477                 return; // instead of break: to avoid re-entering hci_run()
2478             }
2479             hci_stack->acl_fragmentation_tx_active = 0;
2480             if (hci_stack->acl_fragmentation_total_size) break;
2481             hci_release_packet_buffer();
2482 
2483             // L2CAP receives this event via the hci_emit_event below
2484 
2485 #ifdef ENABLE_CLASSIC
2486             // For SCO, we do the can_send_now_check here
2487             hci_notify_if_sco_can_send_now();
2488 #endif
2489             break;
2490 
2491 #ifdef ENABLE_CLASSIC
2492         case HCI_EVENT_SCO_CAN_SEND_NOW:
2493             // For SCO, we do the can_send_now_check here
2494             hci_stack->sco_can_send_now = 1;
2495             hci_notify_if_sco_can_send_now();
2496             return;
2497 
2498         // explode inquriy results for easier consumption
2499         case HCI_EVENT_INQUIRY_RESULT:
2500         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2501         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2502             gap_inquiry_explode(packet, size);
2503             break;
2504 #endif
2505 
2506 #ifdef ENABLE_BLE
2507         case HCI_EVENT_LE_META:
2508             switch (packet[2]){
2509 #ifdef ENABLE_LE_CENTRAL
2510                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2511                     // log_info("advertising report received");
2512                     if (!hci_stack->le_scanning_enabled) break;
2513                     le_handle_advertisement_report(packet, size);
2514                     break;
2515 #endif
2516                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2517                     // Connection management
2518                     reverse_bd_addr(&packet[8], addr);
2519                     addr_type = (bd_addr_type_t)packet[7];
2520                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2521                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2522 
2523 #ifdef ENABLE_LE_CENTRAL
2524                     // if auto-connect, remove from whitelist in both roles
2525                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2526                         hci_remove_from_whitelist(addr_type, addr);
2527                     }
2528                     // handle error: error is reported only to the initiator -> outgoing connection
2529                     if (packet[3]){
2530 
2531                         // handle cancelled outgoing connection
2532                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2533                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2534                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2535                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2536                             conn = gap_get_outgoing_connection();
2537                         }
2538 
2539                         // outgoing connection establishment is done
2540                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2541                         // remove entry
2542                         if (conn){
2543                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2544                             btstack_memory_hci_connection_free( conn );
2545                         }
2546                         break;
2547                     }
2548 #endif
2549                     // on success, both hosts receive connection complete event
2550                     if (packet[6] == HCI_ROLE_MASTER){
2551 #ifdef ENABLE_LE_CENTRAL
2552                         // if we're master, it was an outgoing connection and we're done with it
2553                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2554 #endif
2555                     } else {
2556 #ifdef ENABLE_LE_PERIPHERAL
2557                         // if we're slave, it was an incoming connection, advertisements have stopped
2558                         hci_stack->le_advertisements_active = 0;
2559 #endif
2560                     }
2561                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2562                     if (!conn){
2563                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2564                     }
2565                     // no memory, sorry.
2566                     if (!conn){
2567                         break;
2568                     }
2569 
2570                     conn->state = OPEN;
2571                     conn->role  = packet[6];
2572                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2573                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2574 
2575 #ifdef ENABLE_LE_PERIPHERAL
2576                     if (packet[6] == HCI_ROLE_SLAVE){
2577                         hci_reenable_advertisements_if_needed();
2578                     }
2579 #endif
2580 
2581                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2582 
2583                     // restart timer
2584                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2585                     // btstack_run_loop_add_timer(&conn->timeout);
2586 
2587                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2588 
2589                     hci_emit_nr_connections_changed();
2590                     break;
2591 
2592                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2593                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2594                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2595                     conn = hci_connection_for_handle(handle);
2596                     if (!conn) break;
2597                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2598                     break;
2599 
2600                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2601                     // connection
2602                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2603                     conn = hci_connection_for_handle(handle);
2604                     if (conn) {
2605                         // read arguments
2606                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2607                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2608                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2609                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2610 
2611                         // validate against current connection parameter range
2612                         le_connection_parameter_range_t existing_range;
2613                         gap_get_connection_parameter_range(&existing_range);
2614                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2615                         if (update_parameter){
2616                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2617                             conn->le_conn_interval_min = le_conn_interval_min;
2618                             conn->le_conn_interval_max = le_conn_interval_max;
2619                             conn->le_conn_latency = le_conn_latency;
2620                             conn->le_supervision_timeout = le_supervision_timeout;
2621                         } else {
2622                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2623                         }
2624                     }
2625                     break;
2626 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2627                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2628                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2629                     conn = hci_connection_for_handle(handle);
2630                     if (conn) {
2631                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2632                     }
2633                     break;
2634 #endif
2635                 default:
2636                     break;
2637             }
2638             break;
2639 #endif
2640         case HCI_EVENT_VENDOR_SPECIFIC:
2641             // Vendor specific commands often create vendor specific event instead of num completed packets
2642             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2643             switch (hci_stack->manufacturer){
2644                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2645                     hci_stack->num_cmd_packets = 1;
2646                     break;
2647                 default:
2648                     break;
2649             }
2650             break;
2651         default:
2652             break;
2653     }
2654 
2655     handle_event_for_current_stack_state(packet, size);
2656 
2657     // notify upper stack
2658 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2659 
2660     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2661     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2662         if (!packet[2]){
2663             handle = little_endian_read_16(packet, 3);
2664             hci_connection_t * aConn = hci_connection_for_handle(handle);
2665             if (aConn) {
2666                 // discard connection if app did not trigger a reconnect in the event handler
2667                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2668                     hci_shutdown_connection(aConn);
2669                 }
2670             }
2671         }
2672     }
2673 
2674 	// execute main loop
2675 	hci_run();
2676 }
2677 
2678 #ifdef ENABLE_CLASSIC
2679 
2680 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2681 static void sco_schedule_tx(hci_connection_t * conn);
2682 
2683 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2684     log_debug("SCO TX Timeout");
2685     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2686     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2687     if (!conn) return;
2688 
2689     // trigger send
2690     conn->sco_tx_ready = 1;
2691     // extra packet if CVSD but SCO buffer is too short
2692     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2693         conn->sco_tx_ready++;
2694     }
2695     hci_notify_if_sco_can_send_now();
2696 }
2697 
2698 
2699 #define SCO_TX_AFTER_RX_MS (6)
2700 
2701 static void sco_schedule_tx(hci_connection_t * conn){
2702 
2703     uint32_t now = btstack_run_loop_get_time_ms();
2704     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2705     int time_delta_ms = sco_tx_ms - now;
2706 
2707     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2708 
2709     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2710     btstack_run_loop_set_timer(timer, time_delta_ms);
2711     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2712     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2713     btstack_run_loop_add_timer(timer);
2714 }
2715 
2716 static void sco_handler(uint8_t * packet, uint16_t size){
2717     // lookup connection struct
2718     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2719     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2720     if (!conn) return;
2721 
2722     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2723     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2724         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2725             packet[2] = 0x3c;
2726             memmove(&packet[3], &packet[23], 63);
2727             size = 63;
2728         }
2729     }
2730 
2731     if (hci_have_usb_transport()){
2732         // Nothing to do
2733     } else {
2734         // 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);
2735         if (hci_stack->synchronous_flow_control_enabled == 0){
2736             uint32_t now = btstack_run_loop_get_time_ms();
2737 
2738             if (!conn->sco_rx_valid){
2739                 // ignore first 10 packets
2740                 conn->sco_rx_count++;
2741                 // log_debug("sco rx count %u", conn->sco_rx_count);
2742                 if (conn->sco_rx_count == 10) {
2743                     // use first timestamp as is and pretent it just started
2744                     conn->sco_rx_ms = now;
2745                     conn->sco_rx_valid = 1;
2746                     conn->sco_rx_count = 0;
2747                     sco_schedule_tx(conn);
2748                 }
2749             } else {
2750                 // track expected arrival timme
2751                 conn->sco_rx_count++;
2752                 conn->sco_rx_ms += 7;
2753                 int delta = (int32_t) (now - conn->sco_rx_ms);
2754                 if (delta > 0){
2755                     conn->sco_rx_ms++;
2756                 }
2757                 // log_debug("sco rx %u", conn->sco_rx_ms);
2758                 sco_schedule_tx(conn);
2759             }
2760         }
2761     }
2762     // deliver to app
2763     if (hci_stack->sco_packet_handler) {
2764         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2765     }
2766 
2767 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2768     conn->num_packets_completed++;
2769     hci_stack->host_completed_packets = 1;
2770     hci_run();
2771 #endif
2772 }
2773 #endif
2774 
2775 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2776     hci_dump_packet(packet_type, 1, packet, size);
2777     switch (packet_type) {
2778         case HCI_EVENT_PACKET:
2779             event_handler(packet, size);
2780             break;
2781         case HCI_ACL_DATA_PACKET:
2782             acl_handler(packet, size);
2783             break;
2784 #ifdef ENABLE_CLASSIC
2785         case HCI_SCO_DATA_PACKET:
2786             sco_handler(packet, size);
2787             break;
2788 #endif
2789         default:
2790             break;
2791     }
2792 }
2793 
2794 /**
2795  * @brief Add event packet handler.
2796  */
2797 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2798     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2799 }
2800 
2801 
2802 /** Register HCI packet handlers */
2803 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2804     hci_stack->acl_packet_handler = handler;
2805 }
2806 
2807 #ifdef ENABLE_CLASSIC
2808 /**
2809  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2810  */
2811 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2812     hci_stack->sco_packet_handler = handler;
2813 }
2814 #endif
2815 
2816 static void hci_state_reset(void){
2817     // no connections yet
2818     hci_stack->connections = NULL;
2819 
2820     // keep discoverable/connectable as this has been requested by the client(s)
2821     // hci_stack->discoverable = 0;
2822     // hci_stack->connectable = 0;
2823     // hci_stack->bondable = 1;
2824     // hci_stack->own_addr_type = 0;
2825 
2826     // buffer is free
2827     hci_stack->hci_packet_buffer_reserved = 0;
2828 
2829     // no pending cmds
2830     hci_stack->decline_reason = 0;
2831     hci_stack->new_scan_enable_value = 0xff;
2832 
2833     // LE
2834 #ifdef ENABLE_BLE
2835     memset(hci_stack->le_random_address, 0, 6);
2836     hci_stack->le_random_address_set = 0;
2837 #endif
2838 #ifdef ENABLE_LE_CENTRAL
2839     hci_stack->le_scanning_active  = 0;
2840     hci_stack->le_scan_type = 0xff;
2841     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2842     hci_stack->le_whitelist = 0;
2843     hci_stack->le_whitelist_capacity = 0;
2844 #endif
2845 }
2846 
2847 #ifdef ENABLE_CLASSIC
2848 /**
2849  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2850  */
2851 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2852     // store and open remote device db
2853     hci_stack->link_key_db = link_key_db;
2854     if (hci_stack->link_key_db) {
2855         hci_stack->link_key_db->open();
2856     }
2857 }
2858 #endif
2859 
2860 void hci_init(const hci_transport_t *transport, const void *config){
2861 
2862 #ifdef HAVE_MALLOC
2863     if (!hci_stack) {
2864         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2865     }
2866 #else
2867     hci_stack = &hci_stack_static;
2868 #endif
2869     memset(hci_stack, 0, sizeof(hci_stack_t));
2870 
2871     // reference to use transport layer implementation
2872     hci_stack->hci_transport = transport;
2873 
2874     // reference to used config
2875     hci_stack->config = config;
2876 
2877     // setup pointer for outgoing packet buffer
2878     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2879 
2880     // max acl payload size defined in config.h
2881     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2882 
2883     // register packet handlers with transport
2884     transport->register_packet_handler(&packet_handler);
2885 
2886     hci_stack->state = HCI_STATE_OFF;
2887 
2888     // class of device
2889     hci_stack->class_of_device = 0x007a020c; // Smartphone
2890 
2891     // bondable by default
2892     hci_stack->bondable = 1;
2893 
2894 #ifdef ENABLE_CLASSIC
2895     // classic name
2896     hci_stack->local_name = default_classic_name;
2897 
2898     // Master slave policy
2899     hci_stack->master_slave_policy = 1;
2900 
2901     // Allow Role Switch
2902     hci_stack->allow_role_switch = 1;
2903 
2904     // Default / minimum security level = 2
2905     hci_stack->gap_security_level = LEVEL_2;
2906 
2907     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3, we use 16 as default
2908     hci_stack->gap_required_encyrption_key_size = 16;
2909 #endif
2910 
2911     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
2912     hci_stack->ssp_enable = 1;
2913     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
2914     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
2915     hci_stack->ssp_auto_accept = 1;
2916 
2917     // Secure Connections: enable (requires support from Controller)
2918     hci_stack->secure_connections_enable = true;
2919 
2920     // voice setting - signed 16 bit pcm data with CVSD over the air
2921     hci_stack->sco_voice_setting = 0x60;
2922 
2923 #ifdef ENABLE_LE_CENTRAL
2924     // connection parameter to use for outgoing connections
2925     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
2926     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
2927     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
2928     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
2929     hci_stack->le_connection_latency      = 4;         // 4
2930     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
2931     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
2932     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
2933 
2934     // default LE Scanning
2935     hci_stack->le_scan_interval = 0x1e0;
2936     hci_stack->le_scan_window   =  0x30;
2937 #endif
2938 
2939 #ifdef ENABLE_LE_PERIPHERAL
2940     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
2941 #endif
2942 
2943     // connection parameter range used to answer connection parameter update requests in l2cap
2944     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
2945     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
2946     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
2947     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
2948     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
2949     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
2950 
2951     hci_state_reset();
2952 }
2953 
2954 /**
2955  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
2956  */
2957 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
2958     hci_stack->chipset = chipset_driver;
2959 
2960     // reset chipset driver - init is also called on power_up
2961     if (hci_stack->chipset && hci_stack->chipset->init){
2962         hci_stack->chipset->init(hci_stack->config);
2963     }
2964 }
2965 
2966 /**
2967  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
2968  */
2969 void hci_set_control(const btstack_control_t *hardware_control){
2970     // references to used control implementation
2971     hci_stack->control = hardware_control;
2972     // init with transport config
2973     hardware_control->init(hci_stack->config);
2974 }
2975 
2976 void hci_close(void){
2977     // close remote device db
2978     if (hci_stack->link_key_db) {
2979         hci_stack->link_key_db->close();
2980     }
2981 
2982     btstack_linked_list_iterator_t lit;
2983     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
2984     while (btstack_linked_list_iterator_has_next(&lit)){
2985         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
2986         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
2987         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
2988         hci_shutdown_connection(connection);
2989     }
2990 
2991     hci_power_control(HCI_POWER_OFF);
2992 
2993 #ifdef HAVE_MALLOC
2994     free(hci_stack);
2995 #endif
2996     hci_stack = NULL;
2997 }
2998 
2999 #ifdef ENABLE_CLASSIC
3000 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3001     // validate ranage and set
3002     if (encryption_key_size < 7)  return;
3003     if (encryption_key_size > 16) return;
3004     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3005 }
3006 
3007 void gap_set_security_level(gap_security_level_t security_level){
3008     hci_stack->gap_security_level = security_level;
3009 }
3010 
3011 gap_security_level_t gap_get_security_level(void){
3012     return hci_stack->gap_security_level;
3013 }
3014 #endif
3015 
3016 #ifdef ENABLE_CLASSIC
3017 void gap_set_class_of_device(uint32_t class_of_device){
3018     hci_stack->class_of_device = class_of_device;
3019 }
3020 
3021 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3022     hci_stack->default_link_policy_settings = default_link_policy_settings;
3023 }
3024 
3025 void gap_set_allow_role_switch(bool allow_role_switch){
3026     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3027 }
3028 
3029 uint8_t hci_get_allow_role_switch(void){
3030     return  hci_stack->allow_role_switch;
3031 }
3032 
3033 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3034     hci_stack->link_supervision_timeout = link_supervision_timeout;
3035 }
3036 
3037 void hci_disable_l2cap_timeout_check(void){
3038     disable_l2cap_timeouts = 1;
3039 }
3040 #endif
3041 
3042 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3043 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3044 void hci_set_bd_addr(bd_addr_t addr){
3045     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3046     hci_stack->custom_bd_addr_set = 1;
3047 }
3048 #endif
3049 
3050 // State-Module-Driver overview
3051 // state                    module  low-level
3052 // HCI_STATE_OFF             off      close
3053 // HCI_STATE_INITIALIZING,   on       open
3054 // HCI_STATE_WORKING,        on       open
3055 // HCI_STATE_HALTING,        on       open
3056 // HCI_STATE_SLEEPING,    off/sleep   close
3057 // HCI_STATE_FALLING_ASLEEP  on       open
3058 
3059 static int hci_power_control_on(void){
3060 
3061     // power on
3062     int err = 0;
3063     if (hci_stack->control && hci_stack->control->on){
3064         err = (*hci_stack->control->on)();
3065     }
3066     if (err){
3067         log_error( "POWER_ON failed");
3068         hci_emit_hci_open_failed();
3069         return err;
3070     }
3071 
3072     // int chipset driver
3073     if (hci_stack->chipset && hci_stack->chipset->init){
3074         hci_stack->chipset->init(hci_stack->config);
3075     }
3076 
3077     // init transport
3078     if (hci_stack->hci_transport->init){
3079         hci_stack->hci_transport->init(hci_stack->config);
3080     }
3081 
3082     // open transport
3083     err = hci_stack->hci_transport->open();
3084     if (err){
3085         log_error( "HCI_INIT failed, turning Bluetooth off again");
3086         if (hci_stack->control && hci_stack->control->off){
3087             (*hci_stack->control->off)();
3088         }
3089         hci_emit_hci_open_failed();
3090         return err;
3091     }
3092     return 0;
3093 }
3094 
3095 static void hci_power_control_off(void){
3096 
3097     log_info("hci_power_control_off");
3098 
3099     // close low-level device
3100     hci_stack->hci_transport->close();
3101 
3102     log_info("hci_power_control_off - hci_transport closed");
3103 
3104     // power off
3105     if (hci_stack->control && hci_stack->control->off){
3106         (*hci_stack->control->off)();
3107     }
3108 
3109     log_info("hci_power_control_off - control closed");
3110 
3111     hci_stack->state = HCI_STATE_OFF;
3112 }
3113 
3114 static void hci_power_control_sleep(void){
3115 
3116     log_info("hci_power_control_sleep");
3117 
3118 #if 0
3119     // don't close serial port during sleep
3120 
3121     // close low-level device
3122     hci_stack->hci_transport->close(hci_stack->config);
3123 #endif
3124 
3125     // sleep mode
3126     if (hci_stack->control && hci_stack->control->sleep){
3127         (*hci_stack->control->sleep)();
3128     }
3129 
3130     hci_stack->state = HCI_STATE_SLEEPING;
3131 }
3132 
3133 static int hci_power_control_wake(void){
3134 
3135     log_info("hci_power_control_wake");
3136 
3137     // wake on
3138     if (hci_stack->control && hci_stack->control->wake){
3139         (*hci_stack->control->wake)();
3140     }
3141 
3142 #if 0
3143     // open low-level device
3144     int err = hci_stack->hci_transport->open(hci_stack->config);
3145     if (err){
3146         log_error( "HCI_INIT failed, turning Bluetooth off again");
3147         if (hci_stack->control && hci_stack->control->off){
3148             (*hci_stack->control->off)();
3149         }
3150         hci_emit_hci_open_failed();
3151         return err;
3152     }
3153 #endif
3154 
3155     return 0;
3156 }
3157 
3158 static void hci_power_transition_to_initializing(void){
3159     // set up state machine
3160     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3161     hci_stack->hci_packet_buffer_reserved = 0;
3162     hci_stack->state = HCI_STATE_INITIALIZING;
3163     hci_stack->substate = HCI_INIT_SEND_RESET;
3164 }
3165 
3166 int hci_power_control(HCI_POWER_MODE power_mode){
3167 
3168     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3169 
3170     int err = 0;
3171     switch (hci_stack->state){
3172 
3173         case HCI_STATE_OFF:
3174             switch (power_mode){
3175                 case HCI_POWER_ON:
3176                     err = hci_power_control_on();
3177                     if (err) {
3178                         log_error("hci_power_control_on() error %d", err);
3179                         return err;
3180                     }
3181                     hci_power_transition_to_initializing();
3182                     break;
3183                 case HCI_POWER_OFF:
3184                     // do nothing
3185                     break;
3186                 case HCI_POWER_SLEEP:
3187                     // do nothing (with SLEEP == OFF)
3188                     break;
3189             }
3190             break;
3191 
3192         case HCI_STATE_INITIALIZING:
3193             switch (power_mode){
3194                 case HCI_POWER_ON:
3195                     // do nothing
3196                     break;
3197                 case HCI_POWER_OFF:
3198                     // no connections yet, just turn it off
3199                     hci_power_control_off();
3200                     break;
3201                 case HCI_POWER_SLEEP:
3202                     // no connections yet, just turn it off
3203                     hci_power_control_sleep();
3204                     break;
3205             }
3206             break;
3207 
3208         case HCI_STATE_WORKING:
3209             switch (power_mode){
3210                 case HCI_POWER_ON:
3211                     // do nothing
3212                     break;
3213                 case HCI_POWER_OFF:
3214                     // see hci_run
3215                     hci_stack->state = HCI_STATE_HALTING;
3216                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3217                     break;
3218                 case HCI_POWER_SLEEP:
3219                     // see hci_run
3220                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3221                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3222                     break;
3223             }
3224             break;
3225 
3226         case HCI_STATE_HALTING:
3227             switch (power_mode){
3228                 case HCI_POWER_ON:
3229                     hci_power_transition_to_initializing();
3230                     break;
3231                 case HCI_POWER_OFF:
3232                     // do nothing
3233                     break;
3234                 case HCI_POWER_SLEEP:
3235                     // see hci_run
3236                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3237                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3238                     break;
3239             }
3240             break;
3241 
3242         case HCI_STATE_FALLING_ASLEEP:
3243             switch (power_mode){
3244                 case HCI_POWER_ON:
3245 
3246 #ifdef HAVE_PLATFORM_IPHONE_OS
3247                     // nothing to do, if H4 supports power management
3248                     if (btstack_control_iphone_power_management_enabled()){
3249                         hci_stack->state = HCI_STATE_INITIALIZING;
3250                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3251                         break;
3252                     }
3253 #endif
3254                     hci_power_transition_to_initializing();
3255                     break;
3256                 case HCI_POWER_OFF:
3257                     // see hci_run
3258                     hci_stack->state = HCI_STATE_HALTING;
3259                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3260                     break;
3261                 case HCI_POWER_SLEEP:
3262                     // do nothing
3263                     break;
3264             }
3265             break;
3266 
3267         case HCI_STATE_SLEEPING:
3268             switch (power_mode){
3269                 case HCI_POWER_ON:
3270 
3271 #ifdef HAVE_PLATFORM_IPHONE_OS
3272                     // nothing to do, if H4 supports power management
3273                     if (btstack_control_iphone_power_management_enabled()){
3274                         hci_stack->state = HCI_STATE_INITIALIZING;
3275                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3276                         hci_update_scan_enable();
3277                         break;
3278                     }
3279 #endif
3280                     err = hci_power_control_wake();
3281                     if (err) return err;
3282                     hci_power_transition_to_initializing();
3283                     break;
3284                 case HCI_POWER_OFF:
3285                     hci_stack->state = HCI_STATE_HALTING;
3286                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3287                     break;
3288                 case HCI_POWER_SLEEP:
3289                     // do nothing
3290                     break;
3291             }
3292             break;
3293     }
3294 
3295     // create internal event
3296 	hci_emit_state();
3297 
3298 	// trigger next/first action
3299 	hci_run();
3300 
3301     return 0;
3302 }
3303 
3304 
3305 #ifdef ENABLE_CLASSIC
3306 
3307 static void hci_update_scan_enable(void){
3308     // 2 = page scan, 1 = inq scan
3309     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3310     hci_run();
3311 }
3312 
3313 void gap_discoverable_control(uint8_t enable){
3314     if (enable) enable = 1; // normalize argument
3315 
3316     if (hci_stack->discoverable == enable){
3317         hci_emit_discoverable_enabled(hci_stack->discoverable);
3318         return;
3319     }
3320 
3321     hci_stack->discoverable = enable;
3322     hci_update_scan_enable();
3323 }
3324 
3325 void gap_connectable_control(uint8_t enable){
3326     if (enable) enable = 1; // normalize argument
3327 
3328     // don't emit event
3329     if (hci_stack->connectable == enable) return;
3330 
3331     hci_stack->connectable = enable;
3332     hci_update_scan_enable();
3333 }
3334 #endif
3335 
3336 void gap_local_bd_addr(bd_addr_t address_buffer){
3337     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3338 }
3339 
3340 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3341 static void hci_host_num_completed_packets(void){
3342 
3343     // create packet manually as arrays are not supported and num_commands should not get reduced
3344     hci_reserve_packet_buffer();
3345     uint8_t * packet = hci_get_outgoing_packet_buffer();
3346 
3347     uint16_t size = 0;
3348     uint16_t num_handles = 0;
3349     packet[size++] = 0x35;
3350     packet[size++] = 0x0c;
3351     size++;  // skip param len
3352     size++;  // skip num handles
3353 
3354     // add { handle, packets } entries
3355     btstack_linked_item_t * it;
3356     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3357         hci_connection_t * connection = (hci_connection_t *) it;
3358         if (connection->num_packets_completed){
3359             little_endian_store_16(packet, size, connection->con_handle);
3360             size += 2;
3361             little_endian_store_16(packet, size, connection->num_packets_completed);
3362             size += 2;
3363             //
3364             num_handles++;
3365             connection->num_packets_completed = 0;
3366         }
3367     }
3368 
3369     packet[2] = size - 3;
3370     packet[3] = num_handles;
3371 
3372     hci_stack->host_completed_packets = 0;
3373 
3374     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3375     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3376 
3377     // release packet buffer for synchronous transport implementations
3378     if (hci_transport_synchronous()){
3379         hci_release_packet_buffer();
3380         hci_emit_transport_packet_sent();
3381     }
3382 }
3383 #endif
3384 
3385 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3386     UNUSED(ds);
3387     hci_stack->substate = HCI_HALTING_CLOSE;
3388     // allow packet handlers to defer final shutdown
3389     hci_emit_state();
3390     hci_run();
3391 }
3392 
3393 static bool hci_run_acl_fragments(void){
3394     if (hci_stack->acl_fragmentation_total_size > 0) {
3395         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3396         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3397         if (connection) {
3398             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3399                 hci_send_acl_packet_fragments(connection);
3400                 return true;
3401             }
3402         } else {
3403             // connection gone -> discard further fragments
3404             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3405             hci_stack->acl_fragmentation_total_size = 0;
3406             hci_stack->acl_fragmentation_pos = 0;
3407         }
3408     }
3409     return false;
3410 }
3411 
3412 #ifdef ENABLE_CLASSIC
3413 static bool hci_run_general_gap_classic(void){
3414 
3415     // decline incoming connections
3416     if (hci_stack->decline_reason){
3417         uint8_t reason = hci_stack->decline_reason;
3418         hci_stack->decline_reason = 0;
3419         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3420         return true;
3421     }
3422     // send scan enable
3423     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3424         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3425         hci_stack->new_scan_enable_value = 0xff;
3426         return true;
3427     }
3428     // start/stop inquiry
3429     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3430         uint8_t duration = hci_stack->inquiry_state;
3431         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3432         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3433         return true;
3434     }
3435     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3436         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3437         hci_send_cmd(&hci_inquiry_cancel);
3438         return true;
3439     }
3440     // remote name request
3441     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3442         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3443         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3444                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3445         return true;
3446     }
3447     // pairing
3448     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3449         uint8_t state = hci_stack->gap_pairing_state;
3450         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3451         switch (state){
3452             case GAP_PAIRING_STATE_SEND_PIN:
3453                 hci_send_cmd(&hci_pin_code_request_reply, hci_stack->gap_pairing_addr, strlen(hci_stack->gap_pairing_input.gap_pairing_pin), hci_stack->gap_pairing_input.gap_pairing_pin);
3454                 break;
3455             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3456                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3457                 break;
3458             case GAP_PAIRING_STATE_SEND_PASSKEY:
3459                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3460                 break;
3461             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3462                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3463                 break;
3464             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3465                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3466                 break;
3467             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3468                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3469                 break;
3470             default:
3471                 break;
3472         }
3473         return true;
3474     }
3475     return false;
3476 }
3477 #endif
3478 
3479 #ifdef ENABLE_BLE
3480 static bool hci_run_general_gap_le(void){
3481 
3482     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3483 
3484     if (hci_stack->state != HCI_STATE_WORKING) return false;
3485     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3486 
3487 #ifdef ENABLE_LE_CENTRAL
3488     // parameter change requires scanning to be stopped first
3489     if (hci_stack->le_scan_type != 0xff) {
3490         if (hci_stack->le_scanning_active){
3491             hci_stack->le_scanning_active = 0;
3492             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3493         } else {
3494             int scan_type = (int) hci_stack->le_scan_type;
3495             hci_stack->le_scan_type = 0xff;
3496             hci_send_cmd(&hci_le_set_scan_parameters, scan_type, hci_stack->le_scan_interval, hci_stack->le_scan_window, hci_stack->le_own_addr_type, 0);
3497         }
3498         return true;
3499     }
3500     // finally, we can enable/disable le scan
3501     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3502         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3503         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3504         return true;
3505     }
3506 #endif
3507 #ifdef ENABLE_LE_PERIPHERAL
3508     // le advertisement control
3509     if (hci_stack->le_advertisements_todo){
3510         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3511     }
3512     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3513         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3514         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3515         return true;
3516     }
3517     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3518         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3519         hci_send_cmd(&hci_le_set_advertising_parameters,
3520                      hci_stack->le_advertisements_interval_min,
3521                      hci_stack->le_advertisements_interval_max,
3522                      hci_stack->le_advertisements_type,
3523                      hci_stack->le_own_addr_type,
3524                      hci_stack->le_advertisements_direct_address_type,
3525                      hci_stack->le_advertisements_direct_address,
3526                      hci_stack->le_advertisements_channel_map,
3527                      hci_stack->le_advertisements_filter_policy);
3528         return true;
3529     }
3530     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3531         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3532         uint8_t adv_data_clean[31];
3533         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3534         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3535                      hci_stack->le_advertisements_data_len);
3536         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3537         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3538         return true;
3539     }
3540     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3541         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3542         uint8_t scan_data_clean[31];
3543         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3544         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3545                      hci_stack->le_scan_response_data_len);
3546         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3547         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3548         return true;
3549     }
3550     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3551         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3552         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3553         return true;
3554     }
3555 #endif
3556 
3557 #ifdef ENABLE_LE_CENTRAL
3558     //
3559     // LE Whitelist Management
3560     //
3561 
3562     // check if whitelist needs modification
3563     btstack_linked_list_iterator_t lit;
3564     int modification_pending = 0;
3565     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3566     while (btstack_linked_list_iterator_has_next(&lit)){
3567         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3568         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3569             modification_pending = 1;
3570             break;
3571         }
3572     }
3573 
3574     if (modification_pending){
3575         // stop connnecting if modification pending
3576         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3577             hci_send_cmd(&hci_le_create_connection_cancel);
3578             return true;
3579         }
3580 
3581         // add/remove entries
3582         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3583         while (btstack_linked_list_iterator_has_next(&lit)){
3584             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3585             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3586                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3587                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3588                 return true;
3589             }
3590             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3591                 bd_addr_t address;
3592                 bd_addr_type_t address_type = entry->address_type;
3593                 (void)memcpy(address, entry->address, 6);
3594                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3595                 btstack_memory_whitelist_entry_free(entry);
3596                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3597                 return true;
3598             }
3599         }
3600     }
3601 
3602     // start connecting
3603     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3604          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3605         bd_addr_t null_addr;
3606         memset(null_addr, 0, 6);
3607         hci_send_cmd(&hci_le_create_connection,
3608                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3609                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3610                      1,         // use whitelist
3611                      0,         // peer address type
3612                      null_addr, // peer bd addr
3613                      hci_stack->le_own_addr_type, // our addr type:
3614                      hci_stack->le_connection_interval_min,    // conn interval min
3615                      hci_stack->le_connection_interval_max,    // conn interval max
3616                      hci_stack->le_connection_latency,         // conn latency
3617                      hci_stack->le_supervision_timeout,        // conn latency
3618                      hci_stack->le_minimum_ce_length,          // min ce length
3619                      hci_stack->le_maximum_ce_length           // max ce length
3620         );
3621         return true;
3622     }
3623 #endif
3624     return false;
3625 }
3626 #endif
3627 
3628 static bool hci_run_general_pending_commmands(void){
3629     btstack_linked_item_t * it;
3630     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3631         hci_connection_t * connection = (hci_connection_t *) it;
3632 
3633         switch(connection->state){
3634             case SEND_CREATE_CONNECTION:
3635                 switch(connection->address_type){
3636 #ifdef ENABLE_CLASSIC
3637                     case BD_ADDR_TYPE_ACL:
3638                         log_info("sending hci_create_connection");
3639                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3640                         break;
3641 #endif
3642                     default:
3643 #ifdef ENABLE_BLE
3644 #ifdef ENABLE_LE_CENTRAL
3645                         // track outgoing connection
3646                         hci_stack->outgoing_addr_type = connection->address_type;
3647                         (void)memcpy(hci_stack->outgoing_addr,
3648                                      connection->address, 6);
3649                         log_info("sending hci_le_create_connection");
3650                         hci_send_cmd(&hci_le_create_connection,
3651                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3652                                      hci_stack->le_connection_scan_window,      // conn scan windows
3653                                      0,         // don't use whitelist
3654                                      connection->address_type, // peer address type
3655                                      connection->address,      // peer bd addr
3656                                      hci_stack->le_own_addr_type, // our addr type:
3657                                      hci_stack->le_connection_interval_min,    // conn interval min
3658                                      hci_stack->le_connection_interval_max,    // conn interval max
3659                                      hci_stack->le_connection_latency,         // conn latency
3660                                      hci_stack->le_supervision_timeout,        // conn latency
3661                                      hci_stack->le_minimum_ce_length,          // min ce length
3662                                      hci_stack->le_maximum_ce_length          // max ce length
3663                         );
3664                         connection->state = SENT_CREATE_CONNECTION;
3665 #endif
3666 #endif
3667                         break;
3668                 }
3669                 return true;
3670 
3671 #ifdef ENABLE_CLASSIC
3672             case RECEIVED_CONNECTION_REQUEST:
3673                 connection->role  = HCI_ROLE_SLAVE;
3674                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3675                     log_info("sending hci_accept_connection_request, remote eSCO %u", connection->remote_supported_feature_eSCO);
3676                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3677                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3678                 }
3679                 return true;
3680 #endif
3681 
3682 #ifdef ENABLE_BLE
3683 #ifdef ENABLE_LE_CENTRAL
3684             case SEND_CANCEL_CONNECTION:
3685                 connection->state = SENT_CANCEL_CONNECTION;
3686                 hci_send_cmd(&hci_le_create_connection_cancel);
3687                 return true;
3688 #endif
3689 #endif
3690             case SEND_DISCONNECT:
3691                 connection->state = SENT_DISCONNECT;
3692                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
3693                 return true;
3694 
3695             default:
3696                 break;
3697         }
3698 
3699         // no further commands if connection is about to get shut down
3700         if (connection->state == SENT_DISCONNECT) continue;
3701 
3702         if (connection->authentication_flags & READ_RSSI){
3703             connectionClearAuthenticationFlags(connection, READ_RSSI);
3704             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3705             return true;
3706         }
3707 
3708 #ifdef ENABLE_CLASSIC
3709 
3710         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3711             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3712             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3713             return true;
3714         }
3715 
3716         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3717             log_info("responding to link key request");
3718             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3719             link_key_t link_key;
3720             link_key_type_t link_key_type;
3721             if ( hci_stack->link_key_db
3722                  && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type)
3723                  && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level)){
3724                 connection->link_key_type = link_key_type;
3725                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3726             } else {
3727                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3728             }
3729             return true;
3730         }
3731 
3732         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3733             log_info("denying to pin request");
3734             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3735             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3736             return true;
3737         }
3738 
3739         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3740             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3741             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3742             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3743                 // tweak authentication requirements
3744                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3745                 if (connection->bonding_flags & BONDING_DEDICATED){
3746                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3747                 }
3748                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3749                     authreq |= 1;
3750                 }
3751                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3752             } else {
3753                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3754             }
3755             return true;
3756         }
3757 
3758         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3759             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3760             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3761             return true;
3762         }
3763 
3764         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3765             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3766             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3767             return true;
3768         }
3769 
3770         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
3771             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
3772             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3773             return true;
3774         }
3775 
3776         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3777             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3778             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3779             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
3780             return true;
3781         }
3782 
3783         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3784             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3785             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3786             return true;
3787         }
3788 
3789         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3790             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3791             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3792             return true;
3793         }
3794         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3795             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3796             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3797             return true;
3798         }
3799 #endif
3800 
3801         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3802             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3803             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
3804             return true;
3805         }
3806 
3807 #ifdef ENABLE_CLASSIC
3808         uint16_t sniff_min_interval;
3809         switch (connection->sniff_min_interval){
3810             case 0:
3811                 break;
3812             case 0xffff:
3813                 connection->sniff_min_interval = 0;
3814                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3815                 return true;
3816             default:
3817                 sniff_min_interval = connection->sniff_min_interval;
3818                 connection->sniff_min_interval = 0;
3819                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3820                 return true;
3821         }
3822 #endif
3823 
3824 #ifdef ENABLE_BLE
3825         switch (connection->le_con_parameter_update_state){
3826             // response to L2CAP CON PARAMETER UPDATE REQUEST
3827             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3828                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3829                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3830                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3831                              0x0000, 0xffff);
3832                 return true;
3833             case CON_PARAMETER_UPDATE_REPLY:
3834                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3835                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3836                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3837                              0x0000, 0xffff);
3838                 return true;
3839             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3840                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3841                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3842                 return true;
3843             default:
3844                 break;
3845         }
3846         if (connection->le_phy_update_all_phys != 0xff){
3847             uint8_t all_phys = connection->le_phy_update_all_phys;
3848             connection->le_phy_update_all_phys = 0xff;
3849             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);
3850             return true;
3851         }
3852 #endif
3853     }
3854     return false;
3855 }
3856 
3857 static void hci_run(void){
3858 
3859     bool done;
3860 
3861     // send continuation fragments first, as they block the prepared packet buffer
3862     done = hci_run_acl_fragments();
3863     if (done) return;
3864 
3865 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3866     // send host num completed packets next as they don't require num_cmd_packets > 0
3867     if (!hci_can_send_comand_packet_transport()) return;
3868     if (hci_stack->host_completed_packets){
3869         hci_host_num_completed_packets();
3870         return;
3871     }
3872 #endif
3873 
3874     if (!hci_can_send_command_packet_now()) return;
3875 
3876     // global/non-connection oriented commands
3877 
3878 
3879 #ifdef ENABLE_CLASSIC
3880     // general gap classic
3881     done = hci_run_general_gap_classic();
3882     if (done) return;
3883 #endif
3884 
3885 #ifdef ENABLE_BLE
3886     // general gap le
3887     done = hci_run_general_gap_le();
3888     if (done) return;
3889 #endif
3890 
3891     // send pending HCI commands
3892     done = hci_run_general_pending_commmands();
3893     if (done) return;
3894 
3895     // stack state sub statemachines
3896     hci_connection_t * connection;
3897     switch (hci_stack->state){
3898         case HCI_STATE_INITIALIZING:
3899             hci_initializing_run();
3900             break;
3901 
3902         case HCI_STATE_HALTING:
3903 
3904             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
3905             switch (hci_stack->substate){
3906                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
3907                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
3908 
3909 #ifdef ENABLE_BLE
3910 #ifdef ENABLE_LE_CENTRAL
3911                     // free whitelist entries
3912                     {
3913                         btstack_linked_list_iterator_t lit;
3914                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3915                         while (btstack_linked_list_iterator_has_next(&lit)){
3916                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3917                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3918                             btstack_memory_whitelist_entry_free(entry);
3919                         }
3920                     }
3921 #endif
3922 #endif
3923                     // close all open connections
3924                     connection =  (hci_connection_t *) hci_stack->connections;
3925                     if (connection){
3926                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
3927                         if (!hci_can_send_command_packet_now()) return;
3928 
3929                         // check state
3930                         if (connection->state == SENT_DISCONNECT) return;
3931                         connection->state = SENT_DISCONNECT;
3932 
3933                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
3934 
3935                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
3936                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
3937 
3938                         // ... which would be ignored anyway as we shutdown (free) the connection now
3939                         hci_shutdown_connection(connection);
3940 
3941                         // finally, send the disconnect command
3942                         hci_send_cmd(&hci_disconnect, con_handle, 0x13);  // remote closed connection
3943                         return;
3944                     }
3945 
3946                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
3947                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
3948                         log_info("HCI_STATE_HALTING: wait 50 ms");
3949                         hci_stack->substate = HCI_HALTING_W4_TIMER;
3950                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
3951                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
3952                         btstack_run_loop_add_timer(&hci_stack->timeout);
3953                         break;
3954                     }
3955 
3956                     /* fall through */
3957 
3958                 case HCI_HALTING_CLOSE:
3959                     log_info("HCI_STATE_HALTING, calling off");
3960 
3961                     // switch mode
3962                     hci_power_control_off();
3963 
3964                     log_info("HCI_STATE_HALTING, emitting state");
3965                     hci_emit_state();
3966                     log_info("HCI_STATE_HALTING, done");
3967                     break;
3968 
3969                 case HCI_HALTING_W4_TIMER:
3970                     // keep waiting
3971 
3972                     break;
3973                 default:
3974                     break;
3975             }
3976 
3977             break;
3978 
3979         case HCI_STATE_FALLING_ASLEEP:
3980             switch(hci_stack->substate) {
3981                 case HCI_FALLING_ASLEEP_DISCONNECT:
3982                     log_info("HCI_STATE_FALLING_ASLEEP");
3983                     // close all open connections
3984                     connection =  (hci_connection_t *) hci_stack->connections;
3985 
3986 #ifdef HAVE_PLATFORM_IPHONE_OS
3987                     // don't close connections, if H4 supports power management
3988                     if (btstack_control_iphone_power_management_enabled()){
3989                         connection = NULL;
3990                     }
3991 #endif
3992                     if (connection){
3993 
3994                         // send disconnect
3995                         if (!hci_can_send_command_packet_now()) return;
3996 
3997                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
3998                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
3999 
4000                         // send disconnected event right away - causes higher layer connections to get closed, too.
4001                         hci_shutdown_connection(connection);
4002                         return;
4003                     }
4004 
4005                     if (hci_classic_supported()){
4006                         // disable page and inquiry scan
4007                         if (!hci_can_send_command_packet_now()) return;
4008 
4009                         log_info("HCI_STATE_HALTING, disabling inq scans");
4010                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4011 
4012                         // continue in next sub state
4013                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4014                         break;
4015                     }
4016 
4017                     /* fall through */
4018 
4019                 case HCI_FALLING_ASLEEP_COMPLETE:
4020                     log_info("HCI_STATE_HALTING, calling sleep");
4021 #ifdef HAVE_PLATFORM_IPHONE_OS
4022                     // don't actually go to sleep, if H4 supports power management
4023                     if (btstack_control_iphone_power_management_enabled()){
4024                         // SLEEP MODE reached
4025                         hci_stack->state = HCI_STATE_SLEEPING;
4026                         hci_emit_state();
4027                         break;
4028                     }
4029 #endif
4030                     // switch mode
4031                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4032                     hci_emit_state();
4033                     break;
4034 
4035                 default:
4036                     break;
4037             }
4038             break;
4039 
4040         default:
4041             break;
4042     }
4043 }
4044 
4045 int hci_send_cmd_packet(uint8_t *packet, int size){
4046     // house-keeping
4047 
4048     if (IS_COMMAND(packet, hci_write_loopback_mode)){
4049         hci_stack->loopback_mode = packet[3];
4050     }
4051 
4052 #ifdef ENABLE_CLASSIC
4053     bd_addr_t addr;
4054     hci_connection_t * conn;
4055 
4056     // create_connection?
4057     if (IS_COMMAND(packet, hci_create_connection)){
4058         reverse_bd_addr(&packet[3], addr);
4059         log_info("Create_connection to %s", bd_addr_to_str(addr));
4060 
4061         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4062         if (!conn){
4063             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4064             if (!conn){
4065                 // notify client that alloc failed
4066                 hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4067                 return -1; // packet not sent to controller
4068             }
4069             conn->state = SEND_CREATE_CONNECTION;
4070         }
4071         log_info("conn state %u", conn->state);
4072         switch (conn->state){
4073             // if connection active exists
4074             case OPEN:
4075                 // and OPEN, emit connection complete command
4076                 hci_emit_connection_complete(addr, conn->con_handle, 0);
4077                 return -1; // packet not sent to controller
4078             case RECEIVED_DISCONNECTION_COMPLETE:
4079                 // create connection triggered in disconnect complete event, let's do it now
4080                 break;
4081             case SEND_CREATE_CONNECTION:
4082                 // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4083                 break;
4084             default:
4085                 // otherwise, just ignore as it is already in the open process
4086                 return -1; // packet not sent to controller
4087         }
4088         conn->state = SENT_CREATE_CONNECTION;
4089 
4090         // track outgoing connection
4091         hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4092         (void)memcpy(hci_stack->outgoing_addr, addr, 6);
4093     }
4094 
4095     else if (IS_COMMAND(packet, hci_link_key_request_reply)){
4096         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4097     }
4098     else if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
4099         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4100     }
4101 
4102     else if (IS_COMMAND(packet, hci_delete_stored_link_key)){
4103         if (hci_stack->link_key_db){
4104             reverse_bd_addr(&packet[3], addr);
4105             hci_stack->link_key_db->delete_link_key(addr);
4106         }
4107     }
4108 
4109     else if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
4110     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
4111         reverse_bd_addr(&packet[3], addr);
4112         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4113         if (conn){
4114             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4115         }
4116     }
4117 
4118     else if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
4119     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
4120     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
4121     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
4122         reverse_bd_addr(&packet[3], addr);
4123         conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4124         if (conn){
4125             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4126         }
4127     }
4128 
4129 #ifdef ENABLE_SCO_OVER_HCI
4130     // setup_synchronous_connection? Voice setting at offset 22
4131     else if (IS_COMMAND(packet, hci_setup_synchronous_connection)){
4132         // TODO: compare to current setting if sco connection already active
4133         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4134     }
4135     // accept_synchronus_connection? Voice setting at offset 18
4136     else if (IS_COMMAND(packet, hci_accept_synchronous_connection)){
4137         // TODO: compare to current setting if sco connection already active
4138         hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4139     }
4140 #endif
4141 #endif
4142 
4143 #ifdef ENABLE_BLE
4144     else if (IS_COMMAND(packet, hci_le_set_random_address)){
4145         hci_stack->le_random_address_set = 1;
4146         reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4147     }
4148 #ifdef ENABLE_LE_PERIPHERAL
4149     else if (IS_COMMAND(packet, hci_le_set_advertise_enable)){
4150         hci_stack->le_advertisements_active = packet[3];
4151     }
4152 #endif
4153 #ifdef ENABLE_LE_CENTRAL
4154     else if (IS_COMMAND(packet, hci_le_create_connection)){
4155         // white list used?
4156         uint8_t initiator_filter_policy = packet[7];
4157         switch (initiator_filter_policy){
4158             case 0:
4159                 // whitelist not used
4160                 hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4161                 break;
4162             case 1:
4163                 hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4164                 break;
4165             default:
4166                 log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4167                 break;
4168         }
4169     }
4170     else if (IS_COMMAND(packet, hci_le_create_connection_cancel)){
4171         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4172     }
4173 #endif
4174 #endif
4175 
4176     hci_stack->num_cmd_packets--;
4177 
4178     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4179     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4180 }
4181 
4182 // disconnect because of security block
4183 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4184     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4185     if (!connection) return;
4186     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4187 }
4188 
4189 
4190 // Configure Secure Simple Pairing
4191 
4192 #ifdef ENABLE_CLASSIC
4193 
4194 // enable will enable SSP during init
4195 void gap_ssp_set_enable(int enable){
4196     hci_stack->ssp_enable = enable;
4197 }
4198 
4199 static int hci_local_ssp_activated(void){
4200     return gap_ssp_supported() && hci_stack->ssp_enable;
4201 }
4202 
4203 // if set, BTstack will respond to io capability request using authentication requirement
4204 void gap_ssp_set_io_capability(int io_capability){
4205     hci_stack->ssp_io_capability = io_capability;
4206 }
4207 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4208     hci_stack->ssp_authentication_requirement = authentication_requirement;
4209 }
4210 
4211 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4212 void gap_ssp_set_auto_accept(int auto_accept){
4213     hci_stack->ssp_auto_accept = auto_accept;
4214 }
4215 
4216 void gap_secure_connections_enable(bool enable){
4217     hci_stack->secure_connections_enable = enable;
4218 }
4219 
4220 #endif
4221 
4222 // va_list part of hci_send_cmd
4223 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4224     if (!hci_can_send_command_packet_now()){
4225         log_error("hci_send_cmd called but cannot send packet now");
4226         return 0;
4227     }
4228 
4229     // for HCI INITIALIZATION
4230     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4231     hci_stack->last_cmd_opcode = cmd->opcode;
4232 
4233     hci_reserve_packet_buffer();
4234     uint8_t * packet = hci_stack->hci_packet_buffer;
4235     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4236     int err = hci_send_cmd_packet(packet, size);
4237 
4238     // release packet buffer on error or for synchronous transport implementations
4239     if ((err < 0) || hci_transport_synchronous()){
4240         hci_release_packet_buffer();
4241         hci_emit_transport_packet_sent();
4242     }
4243 
4244     return err;
4245 }
4246 
4247 /**
4248  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4249  */
4250 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4251     va_list argptr;
4252     va_start(argptr, cmd);
4253     int res = hci_send_cmd_va_arg(cmd, argptr);
4254     va_end(argptr);
4255     return res;
4256 }
4257 
4258 // Create various non-HCI events.
4259 // TODO: generalize, use table similar to hci_create_command
4260 
4261 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4262     // dump packet
4263     if (dump) {
4264         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4265     }
4266 
4267     // dispatch to all event handlers
4268     btstack_linked_list_iterator_t it;
4269     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4270     while (btstack_linked_list_iterator_has_next(&it)){
4271         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4272         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4273     }
4274 }
4275 
4276 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4277     if (!hci_stack->acl_packet_handler) return;
4278     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4279 }
4280 
4281 #ifdef ENABLE_CLASSIC
4282 static void hci_notify_if_sco_can_send_now(void){
4283     // notify SCO sender if waiting
4284     if (!hci_stack->sco_waiting_for_can_send_now) return;
4285     if (hci_can_send_sco_packet_now()){
4286         hci_stack->sco_waiting_for_can_send_now = 0;
4287         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4288         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4289         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4290     }
4291 }
4292 
4293 // parsing end emitting has been merged to reduce code size
4294 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4295     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4296 
4297     uint8_t * eir_data;
4298     ad_context_t context;
4299     const uint8_t * name;
4300     uint8_t         name_len;
4301 
4302     if (size < 3) return;
4303 
4304     int event_type = hci_event_packet_get_type(packet);
4305     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4306     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4307 
4308     switch (event_type){
4309         case HCI_EVENT_INQUIRY_RESULT:
4310         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4311             if (size != (3 + (num_responses * 14))) return;
4312             break;
4313         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4314             if (size != 257) return;
4315             if (num_responses != 1) return;
4316             break;
4317         default:
4318             return;
4319     }
4320 
4321     // event[1] is set at the end
4322     int i;
4323     for (i=0; i<num_responses;i++){
4324         memset(event, 0, sizeof(event));
4325         event[0] = GAP_EVENT_INQUIRY_RESULT;
4326         uint8_t event_size = 18;    // if name is not set by EIR
4327 
4328         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4329         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4330         (void)memcpy(&event[9],
4331                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4332                      3); // class of device
4333         (void)memcpy(&event[12],
4334                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4335                      2); // clock offset
4336 
4337         switch (event_type){
4338             case HCI_EVENT_INQUIRY_RESULT:
4339                 // 14,15,16,17 = 0, size 18
4340                 break;
4341             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4342                 event[14] = 1;
4343                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4344                 // 16,17 = 0, size 18
4345                 break;
4346             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4347                 event[14] = 1;
4348                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4349                 // EIR packets only contain a single inquiry response
4350                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4351                 name = NULL;
4352                 // Iterate over EIR data
4353                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4354                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4355                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4356                     const uint8_t * data = ad_iterator_get_data(&context);
4357                     // Prefer Complete Local Name over Shortend Local Name
4358                     switch (data_type){
4359                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4360                             if (name) continue;
4361                             /* fall through */
4362                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4363                             name = data;
4364                             name_len = data_size;
4365                             break;
4366                         default:
4367                             break;
4368                     }
4369                 }
4370                 if (name){
4371                     event[16] = 1;
4372                     // truncate name if needed
4373                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4374                     event[17] = len;
4375                     (void)memcpy(&event[18], name, len);
4376                     event_size += len;
4377                 }
4378                 break;
4379         }
4380         event[1] = event_size - 2;
4381         hci_emit_event(event, event_size, 1);
4382     }
4383 }
4384 #endif
4385 
4386 void hci_emit_state(void){
4387     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4388     uint8_t event[3];
4389     event[0] = BTSTACK_EVENT_STATE;
4390     event[1] = sizeof(event) - 2;
4391     event[2] = hci_stack->state;
4392     hci_emit_event(event, sizeof(event), 1);
4393 }
4394 
4395 #ifdef ENABLE_CLASSIC
4396 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4397     uint8_t event[13];
4398     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4399     event[1] = sizeof(event) - 2;
4400     event[2] = status;
4401     little_endian_store_16(event, 3, con_handle);
4402     reverse_bd_addr(address, &event[5]);
4403     event[11] = 1; // ACL connection
4404     event[12] = 0; // encryption disabled
4405     hci_emit_event(event, sizeof(event), 1);
4406 }
4407 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4408     if (disable_l2cap_timeouts) return;
4409     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4410     uint8_t event[4];
4411     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4412     event[1] = sizeof(event) - 2;
4413     little_endian_store_16(event, 2, conn->con_handle);
4414     hci_emit_event(event, sizeof(event), 1);
4415 }
4416 #endif
4417 
4418 #ifdef ENABLE_BLE
4419 #ifdef ENABLE_LE_CENTRAL
4420 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4421     uint8_t event[21];
4422     event[0] = HCI_EVENT_LE_META;
4423     event[1] = sizeof(event) - 2;
4424     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4425     event[3] = status;
4426     little_endian_store_16(event, 4, con_handle);
4427     event[6] = 0; // TODO: role
4428     event[7] = address_type;
4429     reverse_bd_addr(address, &event[8]);
4430     little_endian_store_16(event, 14, 0); // interval
4431     little_endian_store_16(event, 16, 0); // latency
4432     little_endian_store_16(event, 18, 0); // supervision timeout
4433     event[20] = 0; // master clock accuracy
4434     hci_emit_event(event, sizeof(event), 1);
4435 }
4436 #endif
4437 #endif
4438 
4439 static void hci_emit_transport_packet_sent(void){
4440     // notify upper stack that it might be possible to send again
4441     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4442     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4443 }
4444 
4445 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4446     uint8_t event[6];
4447     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4448     event[1] = sizeof(event) - 2;
4449     event[2] = 0; // status = OK
4450     little_endian_store_16(event, 3, con_handle);
4451     event[5] = reason;
4452     hci_emit_event(event, sizeof(event), 1);
4453 }
4454 
4455 static void hci_emit_nr_connections_changed(void){
4456     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4457     uint8_t event[3];
4458     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4459     event[1] = sizeof(event) - 2;
4460     event[2] = nr_hci_connections();
4461     hci_emit_event(event, sizeof(event), 1);
4462 }
4463 
4464 static void hci_emit_hci_open_failed(void){
4465     log_info("BTSTACK_EVENT_POWERON_FAILED");
4466     uint8_t event[2];
4467     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4468     event[1] = sizeof(event) - 2;
4469     hci_emit_event(event, sizeof(event), 1);
4470 }
4471 
4472 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4473     log_info("hci_emit_dedicated_bonding_result %u ", status);
4474     uint8_t event[9];
4475     int pos = 0;
4476     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4477     event[pos++] = sizeof(event) - 2;
4478     event[pos++] = status;
4479     reverse_bd_addr(address, &event[pos]);
4480     hci_emit_event(event, sizeof(event), 1);
4481 }
4482 
4483 
4484 #ifdef ENABLE_CLASSIC
4485 
4486 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4487     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4488     uint8_t event[5];
4489     int pos = 0;
4490     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4491     event[pos++] = sizeof(event) - 2;
4492     little_endian_store_16(event, 2, con_handle);
4493     pos += 2;
4494     event[pos++] = level;
4495     hci_emit_event(event, sizeof(event), 1);
4496 }
4497 
4498 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4499     if (!connection) return LEVEL_0;
4500     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4501     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4502     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4503     // LEVEL 4 always requires 128 bit encrytion key size
4504     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4505         security_level = LEVEL_3;
4506     }
4507     return security_level;
4508 }
4509 
4510 static void hci_emit_discoverable_enabled(uint8_t enabled){
4511     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4512     uint8_t event[3];
4513     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4514     event[1] = sizeof(event) - 2;
4515     event[2] = enabled;
4516     hci_emit_event(event, sizeof(event), 1);
4517 }
4518 
4519 // query if remote side supports eSCO
4520 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4521     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4522     if (!connection) return 0;
4523     return connection->remote_supported_feature_eSCO;
4524 }
4525 
4526 // query if remote side supports SSP
4527 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4528     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4529     if (!connection) return 0;
4530     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
4531 }
4532 
4533 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4534     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4535 }
4536 
4537 // GAP API
4538 /**
4539  * @bbrief enable/disable bonding. default is enabled
4540  * @praram enabled
4541  */
4542 void gap_set_bondable_mode(int enable){
4543     hci_stack->bondable = enable ? 1 : 0;
4544 }
4545 /**
4546  * @brief Get bondable mode.
4547  * @return 1 if bondable
4548  */
4549 int gap_get_bondable_mode(void){
4550     return hci_stack->bondable;
4551 }
4552 
4553 /**
4554  * @brief map link keys to security levels
4555  */
4556 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4557     switch (link_key_type){
4558         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4559             return LEVEL_4;
4560         case COMBINATION_KEY:
4561         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4562             return LEVEL_3;
4563         default:
4564             return LEVEL_2;
4565     }
4566 }
4567 
4568 /**
4569  * @brief map link keys to secure connection yes/no
4570  */
4571 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4572     switch (link_key_type){
4573         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4574         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4575             return 1;
4576         default:
4577             return 0;
4578     }
4579 }
4580 
4581 /**
4582  * @brief map link keys to authenticated
4583  */
4584 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4585     switch (link_key_type){
4586         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4587         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4588             return 1;
4589         default:
4590             return 0;
4591     }
4592 }
4593 
4594 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4595     log_info("gap_mitm_protection_required_for_security_level %u", level);
4596     return level > LEVEL_2;
4597 }
4598 
4599 /**
4600  * @brief get current security level
4601  */
4602 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4603     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4604     if (!connection) return LEVEL_0;
4605     return gap_security_level_for_connection(connection);
4606 }
4607 
4608 /**
4609  * @brief request connection to device to
4610  * @result GAP_AUTHENTICATION_RESULT
4611  */
4612 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4613     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4614     if (!connection){
4615         hci_emit_security_level(con_handle, LEVEL_0);
4616         return;
4617     }
4618     gap_security_level_t current_level = gap_security_level(con_handle);
4619     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4620         requested_level, connection->requested_security_level, current_level);
4621 
4622     // assumption: earlier requested security higher than current level => security request is active
4623     if (current_level < connection->requested_security_level){
4624         if (connection->requested_security_level < requested_level){
4625             // increase requested level as new level is higher
4626 
4627             // TODO: handle re-authentication when done
4628 
4629             connection->requested_security_level = requested_level;
4630         }
4631         return;
4632     }
4633 
4634     // no request active, notify if security sufficient
4635     if (requested_level <= current_level){
4636         hci_emit_security_level(con_handle, current_level);
4637         return;
4638     }
4639 
4640     // start pairing to increase security level
4641     connection->requested_security_level = requested_level;
4642 
4643 #if 0
4644     // sending encryption request without a link key results in an error.
4645     // TODO: figure out how to use it properly
4646 
4647     // would enabling ecnryption suffice (>= LEVEL_2)?
4648     if (hci_stack->link_key_db){
4649         link_key_type_t link_key_type;
4650         link_key_t      link_key;
4651         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4652             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4653                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4654                 return;
4655             }
4656         }
4657     }
4658 #endif
4659 
4660     // start to authenticate connection
4661     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4662     hci_run();
4663 }
4664 
4665 /**
4666  * @brief start dedicated bonding with device. disconnect after bonding
4667  * @param device
4668  * @param request MITM protection
4669  * @result GAP_DEDICATED_BONDING_COMPLETE
4670  */
4671 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4672 
4673     // create connection state machine
4674     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4675 
4676     if (!connection){
4677         return BTSTACK_MEMORY_ALLOC_FAILED;
4678     }
4679 
4680     // delete linkn key
4681     gap_drop_link_key_for_bd_addr(device);
4682 
4683     // configure LEVEL_2/3, dedicated bonding
4684     connection->state = SEND_CREATE_CONNECTION;
4685     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4686     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4687     connection->bonding_flags = BONDING_DEDICATED;
4688 
4689     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4690 
4691     // handle: connnection failure (connection complete != ok)
4692     // handle: authentication failure
4693     // handle: disconnect on done
4694 
4695     hci_run();
4696 
4697     return 0;
4698 }
4699 #endif
4700 
4701 void gap_set_local_name(const char * local_name){
4702     hci_stack->local_name = local_name;
4703 }
4704 
4705 
4706 #ifdef ENABLE_BLE
4707 
4708 #ifdef ENABLE_LE_CENTRAL
4709 void gap_start_scan(void){
4710     hci_stack->le_scanning_enabled = 1;
4711     hci_run();
4712 }
4713 
4714 void gap_stop_scan(void){
4715     hci_stack->le_scanning_enabled = 0;
4716     hci_run();
4717 }
4718 
4719 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4720     hci_stack->le_scan_type     = scan_type;
4721     hci_stack->le_scan_interval = scan_interval;
4722     hci_stack->le_scan_window   = scan_window;
4723     hci_run();
4724 }
4725 
4726 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4727     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4728     if (!conn){
4729         log_info("gap_connect: no connection exists yet, creating context");
4730         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4731         if (!conn){
4732             // notify client that alloc failed
4733             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4734             log_info("gap_connect: failed to alloc hci_connection_t");
4735             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4736         }
4737         conn->state = SEND_CREATE_CONNECTION;
4738         log_info("gap_connect: send create connection next");
4739         hci_run();
4740         return ERROR_CODE_SUCCESS;
4741     }
4742 
4743     if (!hci_is_le_connection(conn) ||
4744         (conn->state == SEND_CREATE_CONNECTION) ||
4745         (conn->state == SENT_CREATE_CONNECTION)) {
4746         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4747         log_error("gap_connect: classic connection or connect is already being created");
4748         return GATT_CLIENT_IN_WRONG_STATE;
4749     }
4750 
4751     // check if connection was just disconnected
4752     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4753         log_info("gap_connect: send create connection (again)");
4754         conn->state = SEND_CREATE_CONNECTION;
4755         hci_run();
4756         return ERROR_CODE_SUCCESS;
4757     }
4758 
4759     log_info("gap_connect: context exists with state %u", conn->state);
4760     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4761     hci_run();
4762     return ERROR_CODE_SUCCESS;
4763 }
4764 
4765 // @assumption: only a single outgoing LE Connection exists
4766 static hci_connection_t * gap_get_outgoing_connection(void){
4767     btstack_linked_item_t *it;
4768     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4769         hci_connection_t * conn = (hci_connection_t *) it;
4770         if (!hci_is_le_connection(conn)) continue;
4771         switch (conn->state){
4772             case SEND_CREATE_CONNECTION:
4773             case SENT_CREATE_CONNECTION:
4774             case SENT_CANCEL_CONNECTION:
4775                 return conn;
4776             default:
4777                 break;
4778         };
4779     }
4780     return NULL;
4781 }
4782 
4783 uint8_t gap_connect_cancel(void){
4784     hci_connection_t * conn = gap_get_outgoing_connection();
4785     if (!conn) return 0;
4786     switch (conn->state){
4787         case SEND_CREATE_CONNECTION:
4788             // skip sending create connection and emit event instead
4789             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4790             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4791             btstack_memory_hci_connection_free( conn );
4792             break;
4793         case SENT_CREATE_CONNECTION:
4794             // request to send cancel connection
4795             conn->state = SEND_CANCEL_CONNECTION;
4796             hci_run();
4797             break;
4798         default:
4799             break;
4800     }
4801     return 0;
4802 }
4803 #endif
4804 
4805 #ifdef ENABLE_LE_CENTRAL
4806 /**
4807  * @brief Set connection parameters for outgoing connections
4808  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4809  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4810  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4811  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4812  * @param conn_latency, default: 4
4813  * @param supervision_timeout (unit: 10ms), default: 720 ms
4814  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4815  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4816  */
4817 
4818 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4819     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4820     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4821     hci_stack->le_connection_scan_interval = conn_scan_interval;
4822     hci_stack->le_connection_scan_window = conn_scan_window;
4823     hci_stack->le_connection_interval_min = conn_interval_min;
4824     hci_stack->le_connection_interval_max = conn_interval_max;
4825     hci_stack->le_connection_latency = conn_latency;
4826     hci_stack->le_supervision_timeout = supervision_timeout;
4827     hci_stack->le_minimum_ce_length = min_ce_length;
4828     hci_stack->le_maximum_ce_length = max_ce_length;
4829 }
4830 #endif
4831 
4832 /**
4833  * @brief Updates the connection parameters for a given LE connection
4834  * @param handle
4835  * @param conn_interval_min (unit: 1.25ms)
4836  * @param conn_interval_max (unit: 1.25ms)
4837  * @param conn_latency
4838  * @param supervision_timeout (unit: 10ms)
4839  * @returns 0 if ok
4840  */
4841 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4842     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4843     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4844     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4845     connection->le_conn_interval_min = conn_interval_min;
4846     connection->le_conn_interval_max = conn_interval_max;
4847     connection->le_conn_latency = conn_latency;
4848     connection->le_supervision_timeout = supervision_timeout;
4849     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
4850     hci_run();
4851     return 0;
4852 }
4853 
4854 /**
4855  * @brief Request an update of the connection parameter for a given LE connection
4856  * @param handle
4857  * @param conn_interval_min (unit: 1.25ms)
4858  * @param conn_interval_max (unit: 1.25ms)
4859  * @param conn_latency
4860  * @param supervision_timeout (unit: 10ms)
4861  * @returns 0 if ok
4862  */
4863 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4864     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4865     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4866     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
4867     connection->le_conn_interval_min = conn_interval_min;
4868     connection->le_conn_interval_max = conn_interval_max;
4869     connection->le_conn_latency = conn_latency;
4870     connection->le_supervision_timeout = supervision_timeout;
4871     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
4872     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
4873     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
4874     return 0;
4875 }
4876 
4877 #ifdef ENABLE_LE_PERIPHERAL
4878 
4879 static void gap_advertisments_changed(void){
4880     // disable advertisements before updating adv, scan data, or adv params
4881     if (hci_stack->le_advertisements_active){
4882         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
4883     }
4884     hci_run();
4885 }
4886 
4887 /**
4888  * @brief Set Advertisement Data
4889  * @param advertising_data_length
4890  * @param advertising_data (max 31 octets)
4891  * @note data is not copied, pointer has to stay valid
4892  */
4893 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
4894     hci_stack->le_advertisements_data_len = advertising_data_length;
4895     hci_stack->le_advertisements_data = advertising_data;
4896     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
4897     gap_advertisments_changed();
4898 }
4899 
4900 /**
4901  * @brief Set Scan Response Data
4902  * @param advertising_data_length
4903  * @param advertising_data (max 31 octets)
4904  * @note data is not copied, pointer has to stay valid
4905  */
4906 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
4907     hci_stack->le_scan_response_data_len = scan_response_data_length;
4908     hci_stack->le_scan_response_data = scan_response_data;
4909     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
4910     gap_advertisments_changed();
4911 }
4912 
4913 /**
4914  * @brief Set Advertisement Parameters
4915  * @param adv_int_min
4916  * @param adv_int_max
4917  * @param adv_type
4918  * @param direct_address_type
4919  * @param direct_address
4920  * @param channel_map
4921  * @param filter_policy
4922  *
4923  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
4924  */
4925  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
4926     uint8_t direct_address_typ, bd_addr_t direct_address,
4927     uint8_t channel_map, uint8_t filter_policy) {
4928 
4929     hci_stack->le_advertisements_interval_min = adv_int_min;
4930     hci_stack->le_advertisements_interval_max = adv_int_max;
4931     hci_stack->le_advertisements_type = adv_type;
4932     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
4933     hci_stack->le_advertisements_channel_map = channel_map;
4934     hci_stack->le_advertisements_filter_policy = filter_policy;
4935     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
4936                  6);
4937 
4938     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4939     gap_advertisments_changed();
4940  }
4941 
4942 /**
4943  * @brief Enable/Disable Advertisements
4944  * @param enabled
4945  */
4946 void gap_advertisements_enable(int enabled){
4947     hci_stack->le_advertisements_enabled = enabled;
4948     if (enabled && !hci_stack->le_advertisements_active){
4949         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
4950     }
4951     if (!enabled && hci_stack->le_advertisements_active){
4952         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
4953     }
4954     hci_run();
4955 }
4956 
4957 #endif
4958 
4959 void hci_le_set_own_address_type(uint8_t own_address_type){
4960     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
4961     if (own_address_type == hci_stack->le_own_addr_type) return;
4962     hci_stack->le_own_addr_type = own_address_type;
4963 
4964 #ifdef ENABLE_LE_PERIPHERAL
4965     // update advertisement parameters, too
4966     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
4967     gap_advertisments_changed();
4968 #endif
4969 #ifdef ENABLE_LE_CENTRAL
4970     // note: we don't update scan parameters or modify ongoing connection attempts
4971 #endif
4972 }
4973 
4974 #endif
4975 
4976 uint8_t gap_disconnect(hci_con_handle_t handle){
4977     hci_connection_t * conn = hci_connection_for_handle(handle);
4978     if (!conn){
4979         hci_emit_disconnection_complete(handle, 0);
4980         return 0;
4981     }
4982     // ignore if already disconnected
4983     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4984         return 0;
4985     }
4986     conn->state = SEND_DISCONNECT;
4987     hci_run();
4988     return 0;
4989 }
4990 
4991 int gap_read_rssi(hci_con_handle_t con_handle){
4992     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
4993     if (hci_connection == NULL) return 0;
4994     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
4995     hci_run();
4996     return 1;
4997 }
4998 
4999 /**
5000  * @brief Get connection type
5001  * @param con_handle
5002  * @result connection_type
5003  */
5004 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5005     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5006     if (!conn) return GAP_CONNECTION_INVALID;
5007     switch (conn->address_type){
5008         case BD_ADDR_TYPE_LE_PUBLIC:
5009         case BD_ADDR_TYPE_LE_RANDOM:
5010             return GAP_CONNECTION_LE;
5011         case BD_ADDR_TYPE_SCO:
5012             return GAP_CONNECTION_SCO;
5013         case BD_ADDR_TYPE_ACL:
5014             return GAP_CONNECTION_ACL;
5015         default:
5016             return GAP_CONNECTION_INVALID;
5017     }
5018 }
5019 
5020 #ifdef ENABLE_BLE
5021 
5022 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){
5023     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5024     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5025 
5026     conn->le_phy_update_all_phys    = all_phys;
5027     conn->le_phy_update_tx_phys     = tx_phys;
5028     conn->le_phy_update_rx_phys     = rx_phys;
5029     conn->le_phy_update_phy_options = phy_options;
5030 
5031     hci_run();
5032 
5033     return 0;
5034 }
5035 
5036 #ifdef ENABLE_LE_CENTRAL
5037 /**
5038  * @brief Auto Connection Establishment - Start Connecting to device
5039  * @param address_typ
5040  * @param address
5041  * @returns 0 if ok
5042  */
5043 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5044     // check capacity
5045     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5046     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5047     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5048     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5049     entry->address_type = address_type;
5050     (void)memcpy(entry->address, address, 6);
5051     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5052     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5053     hci_run();
5054     return 0;
5055 }
5056 
5057 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5058     btstack_linked_list_iterator_t it;
5059     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5060     while (btstack_linked_list_iterator_has_next(&it)){
5061         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5062         if (entry->address_type != address_type) continue;
5063         if (memcmp(entry->address, address, 6) != 0) continue;
5064         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5065             // remove from controller if already present
5066             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5067             continue;
5068         }
5069         // direclty remove entry from whitelist
5070         btstack_linked_list_iterator_remove(&it);
5071         btstack_memory_whitelist_entry_free(entry);
5072     }
5073 }
5074 
5075 /**
5076  * @brief Auto Connection Establishment - Stop Connecting to device
5077  * @param address_typ
5078  * @param address
5079  * @returns 0 if ok
5080  */
5081 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5082     hci_remove_from_whitelist(address_type, address);
5083     hci_run();
5084     return 0;
5085 }
5086 
5087 /**
5088  * @brief Auto Connection Establishment - Stop everything
5089  * @note  Convenience function to stop all active auto connection attempts
5090  */
5091 void gap_auto_connection_stop_all(void){
5092     btstack_linked_list_iterator_t it;
5093     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5094     while (btstack_linked_list_iterator_has_next(&it)){
5095         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5096         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5097             // remove from controller if already present
5098             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5099             continue;
5100         }
5101         // directly remove entry from whitelist
5102         btstack_linked_list_iterator_remove(&it);
5103         btstack_memory_whitelist_entry_free(entry);
5104     }
5105     hci_run();
5106 }
5107 
5108 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5109     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5110     if (!conn) return 0;
5111     return conn->le_connection_interval;
5112 }
5113 #endif
5114 #endif
5115 
5116 #ifdef ENABLE_CLASSIC
5117 /**
5118  * @brief Set Extended Inquiry Response data
5119  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5120  * @note has to be done before stack starts up
5121  */
5122 void gap_set_extended_inquiry_response(const uint8_t * data){
5123     hci_stack->eir_data = data;
5124 }
5125 
5126 /**
5127  * @brief Start GAP Classic Inquiry
5128  * @param duration in 1.28s units
5129  * @return 0 if ok
5130  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5131  */
5132 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5133     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5134     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5135     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5136         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5137     }
5138     hci_stack->inquiry_state = duration_in_1280ms_units;
5139     hci_run();
5140     return 0;
5141 }
5142 
5143 /**
5144  * @brief Stop GAP Classic Inquiry
5145  * @returns 0 if ok
5146  */
5147 int gap_inquiry_stop(void){
5148     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5149         // emit inquiry complete event, before it even started
5150         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5151         hci_emit_event(event, sizeof(event), 1);
5152         return 0;
5153     }
5154     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5155     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5156     hci_run();
5157     return 0;
5158 }
5159 
5160 
5161 /**
5162  * @brief Remote Name Request
5163  * @param addr
5164  * @param page_scan_repetition_mode
5165  * @param clock_offset only used when bit 15 is set
5166  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5167  */
5168 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5169     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5170     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5171     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5172     hci_stack->remote_name_clock_offset = clock_offset;
5173     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5174     hci_run();
5175     return 0;
5176 }
5177 
5178 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5179     hci_stack->gap_pairing_state = state;
5180     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5181     hci_run();
5182     return 0;
5183 }
5184 
5185 /**
5186  * @brief Legacy Pairing Pin Code Response
5187  * @param addr
5188  * @param pin
5189  * @return 0 if ok
5190  */
5191 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5192     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5193     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5194     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5195 }
5196 
5197 /**
5198  * @brief Abort Legacy Pairing
5199  * @param addr
5200  * @param pin
5201  * @return 0 if ok
5202  */
5203 int gap_pin_code_negative(bd_addr_t addr){
5204     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5205     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5206 }
5207 
5208 /**
5209  * @brief SSP Passkey Response
5210  * @param addr
5211  * @param passkey
5212  * @return 0 if ok
5213  */
5214 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5215     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5216     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5217     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5218 }
5219 
5220 /**
5221  * @brief Abort SSP Passkey Entry/Pairing
5222  * @param addr
5223  * @param pin
5224  * @return 0 if ok
5225  */
5226 int gap_ssp_passkey_negative(bd_addr_t addr){
5227     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5228     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5229 }
5230 
5231 /**
5232  * @brief Accept SSP Numeric Comparison
5233  * @param addr
5234  * @param passkey
5235  * @return 0 if ok
5236  */
5237 int gap_ssp_confirmation_response(bd_addr_t addr){
5238     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5239     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5240 }
5241 
5242 /**
5243  * @brief Abort SSP Numeric Comparison/Pairing
5244  * @param addr
5245  * @param pin
5246  * @return 0 if ok
5247  */
5248 int gap_ssp_confirmation_negative(bd_addr_t addr){
5249     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5250     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5251 }
5252 
5253 /**
5254  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5255  * @param inquiry_mode see bluetooth_defines.h
5256  */
5257 void hci_set_inquiry_mode(inquiry_mode_t mode){
5258     hci_stack->inquiry_mode = mode;
5259 }
5260 
5261 /**
5262  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5263  */
5264 void hci_set_sco_voice_setting(uint16_t voice_setting){
5265     hci_stack->sco_voice_setting = voice_setting;
5266 }
5267 
5268 /**
5269  * @brief Get SCO Voice Setting
5270  * @return current voice setting
5271  */
5272 uint16_t hci_get_sco_voice_setting(void){
5273     return hci_stack->sco_voice_setting;
5274 }
5275 
5276 static int hci_have_usb_transport(void){
5277     if (!hci_stack->hci_transport) return 0;
5278     const char * transport_name = hci_stack->hci_transport->name;
5279     if (!transport_name) return 0;
5280     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5281 }
5282 
5283 /** @brief Get SCO packet length for current SCO Voice setting
5284  *  @note  Using SCO packets of the exact length is required for USB transfer
5285  *  @return Length of SCO packets in bytes (not audio frames)
5286  */
5287 int hci_get_sco_packet_length(void){
5288     int sco_packet_length = 0;
5289 
5290 #ifdef ENABLE_SCO_OVER_HCI
5291 
5292     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5293     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5294 
5295     if (hci_have_usb_transport()){
5296         // see Core Spec for H2 USB Transfer.
5297         // 3 byte SCO header + 24 bytes per connection
5298         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5299         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5300     } else {
5301         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5302         sco_packet_length = 3 + 60 * multiplier;
5303         // assert that it still fits inside an SCO buffer
5304         if (sco_packet_length > hci_stack->sco_data_packet_length){
5305             sco_packet_length = 3 + 60;
5306         }
5307     }
5308 #endif
5309     return sco_packet_length;
5310 }
5311 
5312 /**
5313 * @brief Sets the master/slave policy
5314 * @param policy (0: attempt to become master, 1: let connecting device decide)
5315 */
5316 void hci_set_master_slave_policy(uint8_t policy){
5317     hci_stack->master_slave_policy = policy;
5318 }
5319 
5320 #endif
5321 
5322 HCI_STATE hci_get_state(void){
5323     return hci_stack->state;
5324 }
5325 
5326 #ifdef ENABLE_CLASSIC
5327 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5328     hci_stack->gap_classic_accept_callback = accept_callback;
5329 }
5330 #endif
5331 
5332 /**
5333  * @brief Set callback for Bluetooth Hardware Error
5334  */
5335 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5336     hci_stack->hardware_error_callback = fn;
5337 }
5338 
5339 void hci_disconnect_all(void){
5340     btstack_linked_list_iterator_t it;
5341     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5342     while (btstack_linked_list_iterator_has_next(&it)){
5343         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5344         if (con->state == SENT_DISCONNECT) continue;
5345         con->state = SEND_DISCONNECT;
5346     }
5347     hci_run();
5348 }
5349 
5350 uint16_t hci_get_manufacturer(void){
5351     return hci_stack->manufacturer;
5352 }
5353 
5354 #ifdef ENABLE_BLE
5355 
5356 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5357     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5358     if (!hci_con) return NULL;
5359     return &hci_con->sm_connection;
5360 }
5361 
5362 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5363 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5364 
5365 int gap_encryption_key_size(hci_con_handle_t con_handle){
5366     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5367     if (hci_connection == NULL) return 0;
5368     if (hci_is_le_connection(hci_connection)){
5369         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5370         if (sm_conn->sm_connection_encrypted) {
5371             return sm_conn->sm_actual_encryption_key_size;
5372         }
5373     }
5374 #ifdef ENABLE_CLASSIC
5375     else {
5376         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5377             return hci_connection->encryption_key_size;
5378         }
5379     }
5380 #endif
5381     return 0;
5382 }
5383 
5384 int gap_authenticated(hci_con_handle_t con_handle){
5385     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5386     if (hci_connection == NULL) return 0;
5387 
5388     switch (hci_connection->address_type){
5389         case BD_ADDR_TYPE_LE_PUBLIC:
5390         case BD_ADDR_TYPE_LE_RANDOM:
5391             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5392             return hci_connection->sm_connection.sm_connection_authenticated;
5393 #ifdef ENABLE_CLASSIC
5394         case BD_ADDR_TYPE_SCO:
5395         case BD_ADDR_TYPE_ACL:
5396             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5397 #endif
5398         default:
5399             return 0;
5400     }
5401 }
5402 
5403 int gap_secure_connection(hci_con_handle_t con_handle){
5404     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5405     if (hci_connection == NULL) return 0;
5406 
5407     switch (hci_connection->address_type){
5408         case BD_ADDR_TYPE_LE_PUBLIC:
5409         case BD_ADDR_TYPE_LE_RANDOM:
5410             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5411             return hci_connection->sm_connection.sm_connection_sc;
5412 #ifdef ENABLE_CLASSIC
5413         case BD_ADDR_TYPE_SCO:
5414         case BD_ADDR_TYPE_ACL:
5415             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5416 #endif
5417         default:
5418             return 0;
5419     }
5420 }
5421 
5422 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5423     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5424     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5425     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5426     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5427     return sm_conn->sm_connection_authorization_state;
5428 }
5429 #endif
5430 
5431 #ifdef ENABLE_CLASSIC
5432 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){
5433     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5434     if (!conn) return GAP_CONNECTION_INVALID;
5435     conn->sniff_min_interval = sniff_min_interval;
5436     conn->sniff_max_interval = sniff_max_interval;
5437     conn->sniff_attempt = sniff_attempt;
5438     conn->sniff_timeout = sniff_timeout;
5439     hci_run();
5440     return 0;
5441 }
5442 
5443 /**
5444  * @brief Exit Sniff mode
5445  * @param con_handle
5446  @ @return 0 if ok
5447  */
5448 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5449     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5450     if (!conn) return GAP_CONNECTION_INVALID;
5451     conn->sniff_min_interval = 0xffff;
5452     hci_run();
5453     return 0;
5454 }
5455 #endif
5456 
5457 void hci_halting_defer(void){
5458     if (hci_stack->state != HCI_STATE_HALTING) return;
5459     switch (hci_stack->substate){
5460         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5461         case HCI_HALTING_CLOSE:
5462             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5463             break;
5464         default:
5465             break;
5466     }
5467 }
5468 
5469 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5470 void hci_setup_test_connections_fuzz(void){
5471     hci_connection_t * conn;
5472 
5473     // default address: 66:55:44:33:00:01
5474     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5475 
5476     // setup Controller info
5477     hci_stack->num_cmd_packets = 255;
5478     hci_stack->acl_packets_total_num = 255;
5479 
5480     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5481     addr[5] = 0x01;
5482     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5483     conn->con_handle = addr[5];
5484     conn->role  = HCI_ROLE_SLAVE;
5485     conn->state = RECEIVED_CONNECTION_REQUEST;
5486     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5487 
5488     // setup incoming Classic SCO connection with con handle 0x0002
5489     addr[5] = 0x02;
5490     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5491     conn->con_handle = addr[5];
5492     conn->role  = HCI_ROLE_SLAVE;
5493     conn->state = RECEIVED_CONNECTION_REQUEST;
5494     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5495 
5496     // setup ready Classic ACL connection with con handle 0x0003
5497     addr[5] = 0x03;
5498     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5499     conn->con_handle = addr[5];
5500     conn->role  = HCI_ROLE_SLAVE;
5501     conn->state = OPEN;
5502     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5503 
5504     // setup ready Classic SCO connection with con handle 0x0004
5505     addr[5] = 0x04;
5506     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5507     conn->con_handle = addr[5];
5508     conn->role  = HCI_ROLE_SLAVE;
5509     conn->state = OPEN;
5510     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5511 
5512     // setup ready LE ACL connection with con handle 0x005 and public address
5513     addr[5] = 0x05;
5514     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5515     conn->con_handle = addr[5];
5516     conn->role  = HCI_ROLE_SLAVE;
5517     conn->state = OPEN;
5518     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5519 }
5520 
5521 void hci_free_connections_fuzz(void){
5522     btstack_linked_list_iterator_t it;
5523     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5524     while (btstack_linked_list_iterator_has_next(&it)){
5525         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5526         btstack_linked_list_iterator_remove(&it);
5527         btstack_memory_hci_connection_free(con);
5528     }
5529 }
5530 void hci_simulate_working_fuzz(void){
5531     hci_init_done();
5532     hci_stack->num_cmd_packets = 255;
5533 }
5534 #endif
5535