xref: /btstack/src/hci.c (revision 14b5610872ee1f7271a4c3c814e41e7057e629df)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 #define BTSTACK_FILE__ "hci.c"
39 
40 /*
41  *  hci.c
42  *
43  *  Created by Matthias Ringwald on 4/29/09.
44  *
45  */
46 
47 #include "btstack_config.h"
48 
49 
50 #ifdef ENABLE_CLASSIC
51 #ifdef HAVE_EMBEDDED_TICK
52 #include "btstack_run_loop_embedded.h"
53 #endif
54 #endif
55 
56 #ifdef HAVE_PLATFORM_IPHONE_OS
57 #include "../port/ios/src/btstack_control_iphone.h"
58 #endif
59 
60 #ifdef ENABLE_BLE
61 #include "gap.h"
62 #endif
63 
64 #include <stdarg.h>
65 #include <string.h>
66 #include <inttypes.h>
67 
68 #include "btstack_debug.h"
69 #include "btstack_event.h"
70 #include "btstack_linked_list.h"
71 #include "btstack_memory.h"
72 #include "bluetooth_company_id.h"
73 #include "bluetooth_data_types.h"
74 #include "gap.h"
75 #include "hci.h"
76 #include "hci_cmd.h"
77 #include "hci_dump.h"
78 #include "ad_parser.h"
79 
80 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
81 #ifndef HCI_HOST_ACL_PACKET_NUM
82 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_NUM"
83 #endif
84 #ifndef HCI_HOST_ACL_PACKET_LEN
85 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_ACL_PACKET_LEN"
86 #endif
87 #ifndef HCI_HOST_SCO_PACKET_NUM
88 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_NUM"
89 #endif
90 #ifndef HCI_HOST_SCO_PACKET_LEN
91 #error "ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL requires to define HCI_HOST_SCO_PACKET_LEN"
92 #endif
93 #endif
94 
95 #define HCI_CONNECTION_TIMEOUT_MS 10000
96 
97 #ifndef HCI_RESET_RESEND_TIMEOUT_MS
98 #define HCI_RESET_RESEND_TIMEOUT_MS 200
99 #endif
100 
101 // Names are arbitrarily shortened to 32 bytes if not requested otherwise
102 #ifndef GAP_INQUIRY_MAX_NAME_LEN
103 #define GAP_INQUIRY_MAX_NAME_LEN 32
104 #endif
105 
106 // GAP inquiry state: 0 = off, 0x01 - 0x30 = requested duration, 0xfe = active, 0xff = stop requested
107 #define GAP_INQUIRY_DURATION_MIN 0x01
108 #define GAP_INQUIRY_DURATION_MAX 0x30
109 #define GAP_INQUIRY_STATE_ACTIVE 0x80
110 #define GAP_INQUIRY_STATE_IDLE 0
111 #define GAP_INQUIRY_STATE_W2_CANCEL 0x81
112 #define GAP_INQUIRY_STATE_W4_CANCELLED 0x82
113 
114 // GAP Remote Name Request
115 #define GAP_REMOTE_NAME_STATE_IDLE 0
116 #define GAP_REMOTE_NAME_STATE_W2_SEND 1
117 #define GAP_REMOTE_NAME_STATE_W4_COMPLETE 2
118 
119 // GAP Pairing
120 #define GAP_PAIRING_STATE_IDLE                       0
121 #define GAP_PAIRING_STATE_SEND_PIN                   1
122 #define GAP_PAIRING_STATE_SEND_PIN_NEGATIVE          2
123 #define GAP_PAIRING_STATE_SEND_PASSKEY               3
124 #define GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE      4
125 #define GAP_PAIRING_STATE_SEND_CONFIRMATION          5
126 #define GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE 6
127 
128 
129 // prototypes
130 #ifdef ENABLE_CLASSIC
131 static void hci_update_scan_enable(void);
132 static void hci_emit_discoverable_enabled(uint8_t enabled);
133 static int  hci_local_ssp_activated(void);
134 static int  hci_remote_ssp_supported(hci_con_handle_t con_handle);
135 static bool hci_ssp_supported(hci_connection_t * connection);
136 static void hci_notify_if_sco_can_send_now(void);
137 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status);
138 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
139 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level);
140 static void hci_connection_timeout_handler(btstack_timer_source_t *timer);
141 static void hci_connection_timestamp(hci_connection_t *connection);
142 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn);
143 static void gap_inquiry_explode(uint8_t *packet, uint16_t size);
144 #endif
145 
146 static int  hci_power_control_on(void);
147 static void hci_power_control_off(void);
148 static void hci_state_reset(void);
149 static void hci_emit_transport_packet_sent(void);
150 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason);
151 static void hci_emit_nr_connections_changed(void);
152 static void hci_emit_hci_open_failed(void);
153 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status);
154 static void hci_emit_event(uint8_t * event, uint16_t size, int dump);
155 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size);
156 static void hci_run(void);
157 static int  hci_is_le_connection(hci_connection_t * connection);
158 static int  hci_number_free_acl_slots_for_connection_type( bd_addr_type_t address_type);
159 
160 #ifdef ENABLE_CLASSIC
161 static int hci_have_usb_transport(void);
162 #endif
163 
164 #ifdef ENABLE_BLE
165 #ifdef ENABLE_LE_CENTRAL
166 // called from test/ble_client/advertising_data_parser.c
167 void le_handle_advertisement_report(uint8_t *packet, uint16_t size);
168 static 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) == 0) {
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 #ifdef ENABLE_CLASSIC
1909 static void hci_handle_remote_features_page_0(hci_connection_t * conn, const uint8_t * features){
1910     // SSP Controller
1911     if (features[6] & (1 << 3)){
1912         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER;
1913     }
1914     // eSCO
1915     if (features[3] & (1<<7)){
1916         conn->remote_supported_features[0] |= 1;
1917     }
1918     // Extended features
1919     if (features[7] & (1<<7)){
1920         conn->remote_supported_features[0] |= 2;
1921     }
1922 }
1923 
1924 static void hci_handle_remote_features_page_1(hci_connection_t * conn, const uint8_t * features){
1925     // SSP Host
1926     if (features[0] & (1 << 0)){
1927         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP_HOST;
1928     }
1929     // SC Host
1930     if (features[0] & (1 << 3)){
1931         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_HOST;
1932     }
1933 }
1934 
1935 static void hci_handle_remote_features_page_2(hci_connection_t * conn, const uint8_t * features){
1936     // SC Controller
1937     if (features[1] & (1 << 0)){
1938         conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
1939     }
1940 }
1941 
1942 static void hci_handle_remote_features_received(hci_connection_t * conn){
1943     conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
1944     log_info("Remote features %02x, bonding flags %x", conn->remote_supported_features[0], conn->bonding_flags);
1945     if (conn->bonding_flags & BONDING_DEDICATED){
1946         conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1947     }
1948 }
1949 #endif
1950 
1951 static void handle_event_for_current_stack_state(const uint8_t * packet, uint16_t size) {
1952     // handle BT initialization
1953     if (hci_stack->state == HCI_STATE_INITIALIZING) {
1954         hci_initializing_event_handler(packet, size);
1955     }
1956 
1957     // help with BT sleep
1958     if ((hci_stack->state == HCI_STATE_FALLING_ASLEEP)
1959         && (hci_stack->substate == HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE)
1960         && HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_write_scan_enable)) {
1961         hci_initializing_next_state();
1962     }
1963 }
1964 
1965 #ifdef ENABLE_CLASSIC
1966 static void hci_handle_read_encryption_key_size_complete(hci_connection_t * conn, uint8_t encryption_key_size) {
1967     conn->authentication_flags |= CONNECTION_ENCRYPTED;
1968     conn->encryption_key_size = encryption_key_size;
1969 
1970     if ((conn->authentication_flags & CONNECTION_AUTHENTICATED) != 0) {
1971         hci_emit_security_level(conn->con_handle, gap_security_level_for_connection(conn));
1972         return;
1973     }
1974 
1975     // Request Authentication if not already done
1976     if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
1977     conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
1978 }
1979 #endif
1980 
1981 static void handle_command_complete_event(uint8_t * packet, uint16_t size){
1982     UNUSED(size);
1983 
1984     uint16_t manufacturer;
1985 #ifdef ENABLE_CLASSIC
1986     hci_con_handle_t handle;
1987     hci_connection_t * conn;
1988     uint8_t status;
1989 #endif
1990     // get num cmd packets - limit to 1 to reduce complexity
1991     hci_stack->num_cmd_packets = packet[2] ? 1 : 0;
1992 
1993     uint16_t opcode = hci_event_command_complete_get_command_opcode(packet);
1994     switch (opcode){
1995         case HCI_OPCODE_HCI_READ_LOCAL_NAME:
1996             if (packet[5]) break;
1997             // terminate, name 248 chars
1998             packet[6+248] = 0;
1999             log_info("local name: %s", &packet[6]);
2000             break;
2001         case HCI_OPCODE_HCI_READ_BUFFER_SIZE:
2002             // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
2003             if (hci_stack->state != HCI_STATE_INITIALIZING) break;
2004             uint16_t acl_len = little_endian_read_16(packet, 6);
2005             uint16_t sco_len = packet[8];
2006 
2007             // determine usable ACL/SCO payload size
2008             hci_stack->acl_data_packet_length = btstack_min(acl_len, HCI_ACL_PAYLOAD_SIZE);
2009             hci_stack->sco_data_packet_length = btstack_min(sco_len, HCI_ACL_PAYLOAD_SIZE);
2010 
2011             hci_stack->acl_packets_total_num  = little_endian_read_16(packet, 9);
2012             hci_stack->sco_packets_total_num  = little_endian_read_16(packet, 11);
2013 
2014             log_info("hci_read_buffer_size: ACL size module %u -> used %u, count %u / SCO size %u, count %u",
2015                      acl_len, hci_stack->acl_data_packet_length, hci_stack->acl_packets_total_num,
2016                      hci_stack->sco_data_packet_length, hci_stack->sco_packets_total_num);
2017             break;
2018         case HCI_OPCODE_HCI_READ_RSSI:
2019             if (packet[5] == ERROR_CODE_SUCCESS){
2020                 uint8_t event[5];
2021                 event[0] = GAP_EVENT_RSSI_MEASUREMENT;
2022                 event[1] = 3;
2023                 (void)memcpy(&event[2], &packet[6], 3);
2024                 hci_emit_event(event, sizeof(event), 1);
2025             }
2026             break;
2027 #ifdef ENABLE_BLE
2028         case HCI_OPCODE_HCI_LE_READ_BUFFER_SIZE:
2029             hci_stack->le_data_packets_length = little_endian_read_16(packet, 6);
2030             hci_stack->le_acl_packets_total_num = packet[8];
2031             // determine usable ACL payload size
2032             if (HCI_ACL_PAYLOAD_SIZE < hci_stack->le_data_packets_length){
2033                 hci_stack->le_data_packets_length = HCI_ACL_PAYLOAD_SIZE;
2034             }
2035             log_info("hci_le_read_buffer_size: size %u, count %u", hci_stack->le_data_packets_length, hci_stack->le_acl_packets_total_num);
2036             break;
2037 #endif
2038 #ifdef ENABLE_LE_DATA_LENGTH_EXTENSION
2039         case HCI_OPCODE_HCI_LE_READ_MAXIMUM_DATA_LENGTH:
2040             hci_stack->le_supported_max_tx_octets = little_endian_read_16(packet, 6);
2041             hci_stack->le_supported_max_tx_time = little_endian_read_16(packet, 8);
2042             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);
2043             break;
2044 #endif
2045 #ifdef ENABLE_LE_CENTRAL
2046         case HCI_OPCODE_HCI_LE_READ_WHITE_LIST_SIZE:
2047             hci_stack->le_whitelist_capacity = packet[6];
2048             log_info("hci_le_read_white_list_size: size %u", hci_stack->le_whitelist_capacity);
2049             break;
2050 #endif
2051         case HCI_OPCODE_HCI_READ_BD_ADDR:
2052             reverse_bd_addr(&packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], hci_stack->local_bd_addr);
2053             log_info("Local Address, Status: 0x%02x: Addr: %s", packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
2054 #ifdef ENABLE_CLASSIC
2055             if (hci_stack->link_key_db){
2056                 hci_stack->link_key_db->set_local_bd_addr(hci_stack->local_bd_addr);
2057             }
2058 #endif
2059             break;
2060 #ifdef ENABLE_CLASSIC
2061         case HCI_OPCODE_HCI_WRITE_SCAN_ENABLE:
2062             hci_emit_discoverable_enabled(hci_stack->discoverable);
2063             break;
2064         case HCI_OPCODE_HCI_INQUIRY_CANCEL:
2065             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W4_CANCELLED){
2066                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2067                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2068                 hci_emit_event(event, sizeof(event), 1);
2069             }
2070             break;
2071 #endif
2072         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_FEATURES:
2073             (void)memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1], 8);
2074 
2075 #ifdef ENABLE_CLASSIC
2076             // determine usable ACL packet types based on host buffer size and supported features
2077             hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(HCI_ACL_PAYLOAD_SIZE, &hci_stack->local_supported_features[0]);
2078             log_info("Packet types %04x, eSCO %u", hci_stack->packet_types, hci_extended_sco_link_supported());
2079 #endif
2080             // Classic/LE
2081             log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
2082             break;
2083         case HCI_OPCODE_HCI_READ_LOCAL_VERSION_INFORMATION:
2084             manufacturer = little_endian_read_16(packet, 10);
2085             // map Cypress to Broadcom
2086             if (manufacturer  == BLUETOOTH_COMPANY_ID_CYPRESS_SEMICONDUCTOR){
2087                 log_info("Treat Cypress as Broadcom");
2088                 manufacturer = BLUETOOTH_COMPANY_ID_BROADCOM_CORPORATION;
2089                 little_endian_store_16(packet, 10, manufacturer);
2090             }
2091             hci_stack->manufacturer = manufacturer;
2092             log_info("Manufacturer: 0x%04x", hci_stack->manufacturer);
2093             break;
2094         case HCI_OPCODE_HCI_READ_LOCAL_SUPPORTED_COMMANDS:
2095             hci_stack->local_supported_commands[0] =
2096                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+14] & 0x80) >> 7) |  // bit 0 = Octet 14, bit 7 / Read Buffer Size
2097                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+24] & 0x40) >> 5) |  // bit 1 = Octet 24, bit 6 / Write Le Host Supported
2098                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+10] & 0x10) >> 2) |  // bit 2 = Octet 10, bit 4 / Write Synchronous Flow Control Enable
2099                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+18] & 0x08)     ) |  // bit 3 = Octet 18, bit 3 / Write Default Erroneous Data Reporting
2100                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+34] & 0x01) << 4) |  // bit 4 = Octet 34, bit 0 / LE Write Suggested Default Data Length
2101                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x08) << 2) |  // bit 5 = Octet 35, bit 3 / LE Read Maximum Data Length
2102                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+35] & 0x20) << 1) |  // bit 6 = Octet 35, bit 5 / LE Set Default PHY
2103                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+20] & 0x10) << 3);   // bit 7 = Octet 20, bit 4 / Read Encryption Key Size
2104             hci_stack->local_supported_commands[1] =
2105                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+ 2] & 0x40) >> 6) |  // bit 8 = Octet  2, bit 6 / Read Remote Extended Features
2106                 ((packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1+32] & 0x08) >> 2);   // bit 9 = Octet 32, bit 3 / Write Secure Connections Host
2107             log_info("Local supported commands summary %02x - %02x", hci_stack->local_supported_commands[0],  hci_stack->local_supported_commands[1]);
2108             break;
2109 #ifdef ENABLE_CLASSIC
2110         case HCI_OPCODE_HCI_WRITE_SYNCHRONOUS_FLOW_CONTROL_ENABLE:
2111             if (packet[5]) return;
2112             hci_stack->synchronous_flow_control_enabled = 1;
2113             break;
2114         case HCI_OPCODE_HCI_READ_ENCRYPTION_KEY_SIZE:
2115             status = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE];
2116             handle = little_endian_read_16(packet, OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1);
2117             conn   = hci_connection_for_handle(handle);
2118             if (!conn) return;
2119             uint8_t key_size = 0;
2120             if (status == 0){
2121                 key_size = packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+3];
2122                 log_info("Handle %x04x key Size: %u", handle, key_size);
2123             } else {
2124                 log_info("Read Encryption Key Size failed 0x%02x-> assuming insecure connection with key size of 1", status);
2125             }
2126             hci_handle_read_encryption_key_size_complete(conn, key_size);
2127             break;
2128 #endif
2129         default:
2130             break;
2131     }
2132 }
2133 
2134 static void event_handler(uint8_t *packet, int size){
2135 
2136     uint16_t event_length = packet[1];
2137 
2138     // assert packet is complete
2139     if (size != (event_length + 2)){
2140         log_error("event_handler called with packet of wrong size %d, expected %u => dropping packet", size, event_length + 2);
2141         return;
2142     }
2143 
2144     bd_addr_t addr;
2145     bd_addr_type_t addr_type;
2146     hci_con_handle_t handle;
2147     hci_connection_t * conn;
2148     int i;
2149     int create_connection_cmd;
2150 
2151 #ifdef ENABLE_CLASSIC
2152     uint8_t link_type;
2153 #endif
2154 
2155     // log_info("HCI:EVENT:%02x", hci_event_packet_get_type(packet));
2156 
2157     switch (hci_event_packet_get_type(packet)) {
2158 
2159         case HCI_EVENT_COMMAND_COMPLETE:
2160             handle_command_complete_event(packet, size);
2161             break;
2162 
2163         case HCI_EVENT_COMMAND_STATUS:
2164             // get num cmd packets - limit to 1 to reduce complexity
2165             hci_stack->num_cmd_packets = packet[3] ? 1 : 0;
2166 
2167             // check command status to detected failed outgoing connections
2168             create_connection_cmd = 0;
2169 #ifdef ENABLE_CLASSIC
2170             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){
2171                 create_connection_cmd = 1;
2172             }
2173 #endif
2174 #ifdef ENABLE_LE_CENTRAL
2175             if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_le_create_connection)){
2176                 create_connection_cmd = 1;
2177             }
2178 #endif
2179             if (create_connection_cmd) {
2180                 uint8_t status = hci_event_command_status_get_status(packet);
2181                 conn = hci_connection_for_bd_addr_and_type(hci_stack->outgoing_addr, hci_stack->outgoing_addr_type);
2182                 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);
2183 
2184                 // reset outgoing address info
2185                 memset(hci_stack->outgoing_addr, 0, 6);
2186                 hci_stack->outgoing_addr_type = BD_ADDR_TYPE_UNKNOWN;
2187 
2188                 // error => outgoing connection failed
2189                 if ((conn != NULL) && (status != 0)){
2190                     hci_handle_connection_failed(conn, status);
2191                 }
2192             }
2193             break;
2194 
2195         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:{
2196             if (size < 3) return;
2197             uint16_t num_handles = packet[2];
2198             if (size != (3 + num_handles * 4)) return;
2199             uint16_t offset = 3;
2200             for (i=0; i<num_handles;i++){
2201                 handle = little_endian_read_16(packet, offset) & 0x0fff;
2202                 offset += 2;
2203                 uint16_t num_packets = little_endian_read_16(packet, offset);
2204                 offset += 2;
2205 
2206                 conn = hci_connection_for_handle(handle);
2207                 if (!conn){
2208                     log_error("hci_number_completed_packet lists unused con handle %u", handle);
2209                     continue;
2210                 }
2211 
2212                 if (conn->num_packets_sent >= num_packets){
2213                     conn->num_packets_sent -= num_packets;
2214                 } else {
2215                     log_error("hci_number_completed_packets, more packet slots freed then sent.");
2216                     conn->num_packets_sent = 0;
2217                 }
2218                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u", num_packets, handle, conn->num_packets_sent);
2219 
2220 #ifdef ENABLE_CLASSIC
2221                 // For SCO, we do the can_send_now_check here
2222                 hci_notify_if_sco_can_send_now();
2223 #endif
2224             }
2225             break;
2226         }
2227 
2228 #ifdef ENABLE_CLASSIC
2229         case HCI_EVENT_INQUIRY_COMPLETE:
2230             if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_ACTIVE){
2231                 hci_stack->inquiry_state = GAP_INQUIRY_STATE_IDLE;
2232                 uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
2233                 hci_emit_event(event, sizeof(event), 1);
2234             }
2235             break;
2236         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
2237             if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W4_COMPLETE){
2238                 hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_IDLE;
2239             }
2240             break;
2241         case HCI_EVENT_CONNECTION_REQUEST:
2242             reverse_bd_addr(&packet[2], addr);
2243             if (hci_stack->gap_classic_accept_callback != NULL){
2244                 if ((*hci_stack->gap_classic_accept_callback)(addr) == 0){
2245                     hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_UNACCEPTABLE_BD_ADDR;
2246                     bd_addr_copy(hci_stack->decline_addr, addr);
2247                     break;
2248                 }
2249             }
2250 
2251             // TODO: eval COD 8-10
2252             link_type = packet[11];
2253             log_info("Connection_incoming: %s, type %u", bd_addr_to_str(addr), link_type);
2254             addr_type = (link_type == 1) ? BD_ADDR_TYPE_ACL : BD_ADDR_TYPE_SCO;
2255             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2256             if (!conn) {
2257                 conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2258             }
2259             if (!conn) {
2260                 // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
2261                 hci_stack->decline_reason = ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES;
2262                 bd_addr_copy(hci_stack->decline_addr, addr);
2263                 break;
2264             }
2265             conn->role  = HCI_ROLE_SLAVE;
2266             conn->state = RECEIVED_CONNECTION_REQUEST;
2267             // store info about eSCO
2268             if (link_type == 0x02){
2269                 conn->remote_supported_features[0] |= 1;
2270             }
2271             hci_run();
2272             break;
2273 
2274         case HCI_EVENT_CONNECTION_COMPLETE:
2275             // Connection management
2276             reverse_bd_addr(&packet[5], addr);
2277             log_info("Connection_complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2278             addr_type = BD_ADDR_TYPE_ACL;
2279             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2280             if (conn) {
2281                 if (!packet[2]){
2282                     conn->state = OPEN;
2283                     conn->con_handle = little_endian_read_16(packet, 3);
2284 
2285                     // queue get remote feature
2286                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
2287 
2288                     // queue set supervision timeout if we're master
2289                     if ((hci_stack->link_supervision_timeout != 0) && (conn->role == HCI_ROLE_MASTER)){
2290                         connectionSetAuthenticationFlags(conn, WRITE_SUPERVISION_TIMEOUT);
2291                     }
2292 
2293                     // restart timer
2294                     btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2295                     btstack_run_loop_add_timer(&conn->timeout);
2296 
2297                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2298 
2299                     hci_emit_nr_connections_changed();
2300                 } else {
2301                     // connection failed
2302                     hci_handle_connection_failed(conn, packet[2]);
2303                 }
2304             }
2305             break;
2306 
2307         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:
2308             reverse_bd_addr(&packet[5], addr);
2309             log_info("Synchronous Connection Complete (status=%u) %s", packet[2], bd_addr_to_str(addr));
2310             if (packet[2]){
2311                 // connection failed
2312                 break;
2313             }
2314             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2315             if (!conn) {
2316                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
2317             }
2318             if (!conn) {
2319                 break;
2320             }
2321             conn->state = OPEN;
2322             conn->con_handle = little_endian_read_16(packet, 3);
2323 
2324 #ifdef ENABLE_SCO_OVER_HCI
2325             // update SCO
2326             if (conn->address_type == BD_ADDR_TYPE_SCO && hci_stack->hci_transport && hci_stack->hci_transport->set_sco_config){
2327                 hci_stack->hci_transport->set_sco_config(hci_stack->sco_voice_setting_active, hci_number_sco_connections());
2328             }
2329             // trigger can send now
2330             if (hci_have_usb_transport()){
2331                 hci_stack->sco_can_send_now = 1;
2332             }
2333 #endif
2334             break;
2335 
2336         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
2337             handle = little_endian_read_16(packet, 3);
2338             conn = hci_connection_for_handle(handle);
2339             if (!conn) break;
2340             if (!packet[2]){
2341                 const uint8_t * features = &packet[5];
2342                 hci_handle_remote_features_page_0(conn, features);
2343 
2344                 // read extended features if possible
2345                 if (((hci_stack->local_supported_commands[1] & 1) != 0) && ((conn->remote_supported_features[0] & 2) != 0)) {
2346                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
2347                     break;
2348                 }
2349             }
2350             hci_handle_remote_features_received(conn);
2351             break;
2352 
2353         case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE:
2354             handle = little_endian_read_16(packet, 3);
2355             conn = hci_connection_for_handle(handle);
2356             if (!conn) break;
2357             // status = ok, page = 1
2358             if (!packet[2]) {
2359                 uint8_t page_number = packet[5];
2360                 uint8_t maximum_page_number = packet[6];
2361                 const uint8_t * features = &packet[7];
2362                 bool done = false;
2363                 switch (page_number){
2364                     case 1:
2365                         hci_handle_remote_features_page_1(conn, features);
2366                         if (maximum_page_number >= 2){
2367                             // get Secure Connections (Controller) from Page 2 if available
2368                             conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
2369                         } else {
2370                             // otherwise, assume SC (Controller) == SC (Host)
2371                             if ((conn->bonding_flags & BONDING_REMOTE_SUPPORTS_SC_HOST) != 0){
2372                                 conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
2373                             }
2374                             done = true;
2375                         }
2376                         break;
2377                     case 2:
2378                         hci_handle_remote_features_page_2(conn, features);
2379                         done = true;
2380                         break;
2381                     default:
2382                         break;
2383                 }
2384                 if (!done) break;
2385             }
2386             hci_handle_remote_features_received(conn);
2387             break;
2388 
2389         case HCI_EVENT_LINK_KEY_REQUEST:
2390             log_info("HCI_EVENT_LINK_KEY_REQUEST");
2391             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
2392             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
2393             if (hci_stack->bondable && !hci_stack->link_key_db) break;
2394             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
2395             hci_run();
2396             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
2397             return;
2398 
2399         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
2400             reverse_bd_addr(&packet[2], addr);
2401             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
2402             if (!conn) break;
2403             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
2404             link_key_type_t link_key_type = (link_key_type_t)packet[24];
2405             // Change Connection Encryption keeps link key type
2406             if (link_key_type != CHANGED_COMBINATION_KEY){
2407                 conn->link_key_type = link_key_type;
2408             }
2409             gap_store_link_key_for_bd_addr(addr, &packet[8], conn->link_key_type);
2410             // still forward event to allow dismiss of pairing dialog
2411             break;
2412         }
2413 
2414         case HCI_EVENT_PIN_CODE_REQUEST:
2415             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
2416             // non-bondable mode: pin code negative reply will be sent
2417             if (!hci_stack->bondable){
2418                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
2419                 hci_run();
2420                 return;
2421             }
2422             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
2423             if (!hci_stack->link_key_db) break;
2424             hci_event_pin_code_request_get_bd_addr(packet, addr);
2425             hci_stack->link_key_db->delete_link_key(addr);
2426             break;
2427 
2428         case HCI_EVENT_IO_CAPABILITY_REQUEST:
2429             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
2430             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
2431             break;
2432 
2433         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
2434             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2435             if (!hci_stack->ssp_auto_accept) break;
2436             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
2437             break;
2438 
2439         case HCI_EVENT_USER_PASSKEY_REQUEST:
2440             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
2441             if (!hci_stack->ssp_auto_accept) break;
2442             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
2443             break;
2444         case HCI_EVENT_MODE_CHANGE:
2445             handle = hci_event_mode_change_get_handle(packet);
2446             conn = hci_connection_for_handle(handle);
2447             if (!conn) break;
2448             conn->connection_mode = hci_event_mode_change_get_mode(packet);
2449             log_info("HCI_EVENT_MODE_CHANGE, handle 0x%04x, mode %u", handle, conn->connection_mode);
2450             break;
2451 #endif
2452 
2453         case HCI_EVENT_ENCRYPTION_CHANGE:
2454             handle = hci_event_encryption_change_get_connection_handle(packet);
2455             conn = hci_connection_for_handle(handle);
2456             if (!conn) break;
2457             if (hci_event_encryption_change_get_status(packet) == 0) {
2458                 uint8_t encryption_enabled = hci_event_encryption_change_get_encryption_enabled(packet);
2459                 if (encryption_enabled){
2460                     if (hci_is_le_connection(conn)){
2461                         // For LE, we accept connection as encrypted
2462                         conn->authentication_flags |= CONNECTION_ENCRYPTED;
2463                     }
2464 #ifdef ENABLE_CLASSIC
2465                     else {
2466                         // Detect Secure Connection -> Legacy Connection Downgrade Attack (BIAS)
2467                         bool sc_used_during_pairing = gap_secure_connection_for_link_key_type(conn->link_key_type) != 0;
2468                         bool connected_uses_aes_ccm = encryption_enabled == 2;
2469                         if (sc_used_during_pairing && !connected_uses_aes_ccm){
2470                             log_info("SC during pairing, but only E0 now -> abort");
2471                             conn->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
2472                             break;
2473                         }
2474 
2475                         if ((hci_stack->local_supported_commands[0] & 0x80) != 0){
2476                             // For Classic, we need to validate encryption key size first, if possible (== supported by Controller)
2477                             conn->bonding_flags |= BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
2478                         } else {
2479                             // if not, pretend everything is perfect
2480                             hci_handle_read_encryption_key_size_complete(conn, 16);
2481                         }
2482                     }
2483 #endif
2484                 } else {
2485                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
2486                 }
2487             }
2488 
2489             break;
2490 
2491 #ifdef ENABLE_CLASSIC
2492         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
2493             handle = hci_event_authentication_complete_get_connection_handle(packet);
2494             conn = hci_connection_for_handle(handle);
2495             if (!conn) break;
2496 
2497             // ignore authentication event if we didn't request it
2498             if ((conn->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) == 0) break;
2499 
2500             // dedicated bonding: send result and disconnect
2501             if (conn->bonding_flags & BONDING_DEDICATED){
2502                 conn->bonding_flags &= ~BONDING_DEDICATED;
2503                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
2504                 conn->bonding_status = packet[2];
2505                 break;
2506             }
2507 
2508             // authenticated only if auth status == 0
2509             if (hci_event_authentication_complete_get_status(packet) == 0){
2510                 // authenticated
2511                 conn->authentication_flags |= CONNECTION_AUTHENTICATED;
2512 
2513                 // If link key sufficient for requested security and not already encrypted, start encryption
2514                 if (((gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level)) &&
2515                     ((conn->authentication_flags & CONNECTION_ENCRYPTED) == 0)){
2516                     conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2517                     break;
2518                 }
2519             }
2520 
2521             // emit updated security level
2522             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
2523             break;
2524 #endif
2525 
2526         // HCI_EVENT_DISCONNECTION_COMPLETE
2527         // has been split, to first notify stack before shutting connection down
2528         // see end of function, too.
2529         case HCI_EVENT_DISCONNECTION_COMPLETE:
2530             if (packet[2]) break;   // status != 0
2531             handle = little_endian_read_16(packet, 3);
2532             // drop outgoing ACL fragments if it is for closed connection and release buffer if tx not active
2533             if (hci_stack->acl_fragmentation_total_size > 0) {
2534                 if (handle == READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer)){
2535                     int release_buffer = hci_stack->acl_fragmentation_tx_active == 0;
2536                     log_info("drop fragmented ACL data for closed connection, release buffer %u", release_buffer);
2537                     hci_stack->acl_fragmentation_total_size = 0;
2538                     hci_stack->acl_fragmentation_pos = 0;
2539                     if (release_buffer){
2540                         hci_release_packet_buffer();
2541                     }
2542                 }
2543             }
2544 
2545             conn = hci_connection_for_handle(handle);
2546             if (!conn) break;
2547             // mark connection for shutdown
2548             conn->state = RECEIVED_DISCONNECTION_COMPLETE;
2549 
2550             // emit dedicatd bonding event
2551             if (conn->bonding_flags & BONDING_EMIT_COMPLETE_ON_DISCONNECT){
2552                 hci_emit_dedicated_bonding_result(conn->address, conn->bonding_status);
2553             }
2554 
2555 #ifdef ENABLE_BLE
2556 #ifdef ENABLE_LE_PERIPHERAL
2557             // re-enable advertisements for le connections if active
2558             if (hci_is_le_connection(conn)){
2559                 hci_reenable_advertisements_if_needed();
2560             }
2561 #endif
2562 #endif
2563             break;
2564 
2565         case HCI_EVENT_HARDWARE_ERROR:
2566             log_error("Hardware Error: 0x%02x", packet[2]);
2567             if (hci_stack->hardware_error_callback){
2568                 (*hci_stack->hardware_error_callback)(packet[2]);
2569             } else {
2570                 // if no special requests, just reboot stack
2571                 hci_power_control_off();
2572                 hci_power_control_on();
2573             }
2574             break;
2575 
2576 #ifdef ENABLE_CLASSIC
2577         case HCI_EVENT_ROLE_CHANGE:
2578             if (packet[2]) break;   // status != 0
2579             reverse_bd_addr(&packet[3], addr);
2580             addr_type = BD_ADDR_TYPE_ACL;
2581             conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2582             if (!conn) break;
2583             conn->role = packet[9];
2584             break;
2585 #endif
2586 
2587         case HCI_EVENT_TRANSPORT_PACKET_SENT:
2588             // release packet buffer only for asynchronous transport and if there are not further fragements
2589             if (hci_transport_synchronous()) {
2590                 log_error("Synchronous HCI Transport shouldn't send HCI_EVENT_TRANSPORT_PACKET_SENT");
2591                 return; // instead of break: to avoid re-entering hci_run()
2592             }
2593             hci_stack->acl_fragmentation_tx_active = 0;
2594             if (hci_stack->acl_fragmentation_total_size) break;
2595             hci_release_packet_buffer();
2596 
2597             // L2CAP receives this event via the hci_emit_event below
2598 
2599 #ifdef ENABLE_CLASSIC
2600             // For SCO, we do the can_send_now_check here
2601             hci_notify_if_sco_can_send_now();
2602 #endif
2603             break;
2604 
2605 #ifdef ENABLE_CLASSIC
2606         case HCI_EVENT_SCO_CAN_SEND_NOW:
2607             // For SCO, we do the can_send_now_check here
2608             hci_stack->sco_can_send_now = 1;
2609             hci_notify_if_sco_can_send_now();
2610             return;
2611 
2612         // explode inquriy results for easier consumption
2613         case HCI_EVENT_INQUIRY_RESULT:
2614         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
2615         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
2616             gap_inquiry_explode(packet, size);
2617             break;
2618 #endif
2619 
2620 #ifdef ENABLE_BLE
2621         case HCI_EVENT_LE_META:
2622             switch (packet[2]){
2623 #ifdef ENABLE_LE_CENTRAL
2624                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
2625                     // log_info("advertising report received");
2626                     if (!hci_stack->le_scanning_enabled) break;
2627                     le_handle_advertisement_report(packet, size);
2628                     break;
2629 #endif
2630                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
2631                     // Connection management
2632                     reverse_bd_addr(&packet[8], addr);
2633                     addr_type = (bd_addr_type_t)packet[7];
2634                     log_info("LE Connection_complete (status=%u) type %u, %s", packet[3], addr_type, bd_addr_to_str(addr));
2635                     conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2636 
2637 #ifdef ENABLE_LE_CENTRAL
2638                     // if auto-connect, remove from whitelist in both roles
2639                     if (hci_stack->le_connecting_state == LE_CONNECTING_WHITELIST){
2640                         hci_remove_from_whitelist(addr_type, addr);
2641                     }
2642                     // handle error: error is reported only to the initiator -> outgoing connection
2643                     if (packet[3]){
2644 
2645                         // handle cancelled outgoing connection
2646                         // "If the cancellation was successful then, after the Command Complete event for the LE_Create_Connection_Cancel command,
2647                         //  either an LE Connection Complete or an LE Enhanced Connection Complete event shall be generated.
2648                         //  In either case, the event shall be sent with the error code Unknown Connection Identifier (0x02)."
2649                         if (packet[3] == ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER){
2650                             conn = gap_get_outgoing_connection();
2651                         }
2652 
2653                         // outgoing connection establishment is done
2654                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2655                         // remove entry
2656                         if (conn){
2657                             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
2658                             btstack_memory_hci_connection_free( conn );
2659                         }
2660                         break;
2661                     }
2662 #endif
2663                     // on success, both hosts receive connection complete event
2664                     if (packet[6] == HCI_ROLE_MASTER){
2665 #ifdef ENABLE_LE_CENTRAL
2666                         // if we're master, it was an outgoing connection and we're done with it
2667                         hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2668 #endif
2669                     } else {
2670 #ifdef ENABLE_LE_PERIPHERAL
2671                         // if we're slave, it was an incoming connection, advertisements have stopped
2672                         hci_stack->le_advertisements_active = 0;
2673 #endif
2674                     }
2675                     // LE connections are auto-accepted, so just create a connection if there isn't one already
2676                     if (!conn){
2677                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
2678                     }
2679                     // no memory, sorry.
2680                     if (!conn){
2681                         break;
2682                     }
2683 
2684                     conn->state = OPEN;
2685                     conn->role  = packet[6];
2686                     conn->con_handle             = hci_subevent_le_connection_complete_get_connection_handle(packet);
2687                     conn->le_connection_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
2688 
2689 #ifdef ENABLE_LE_PERIPHERAL
2690                     if (packet[6] == HCI_ROLE_SLAVE){
2691                         hci_reenable_advertisements_if_needed();
2692                     }
2693 #endif
2694 
2695                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
2696 
2697                     // restart timer
2698                     // btstack_run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
2699                     // btstack_run_loop_add_timer(&conn->timeout);
2700 
2701                     log_info("New connection: handle %u, %s", conn->con_handle, bd_addr_to_str(conn->address));
2702 
2703                     hci_emit_nr_connections_changed();
2704                     break;
2705 
2706                 // log_info("LE buffer size: %u, count %u", little_endian_read_16(packet,6), packet[8]);
2707                 case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
2708                     handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
2709                     conn = hci_connection_for_handle(handle);
2710                     if (!conn) break;
2711                     conn->le_connection_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
2712                     break;
2713 
2714                 case HCI_SUBEVENT_LE_REMOTE_CONNECTION_PARAMETER_REQUEST:
2715                     // connection
2716                     handle = hci_subevent_le_remote_connection_parameter_request_get_connection_handle(packet);
2717                     conn = hci_connection_for_handle(handle);
2718                     if (conn) {
2719                         // read arguments
2720                         uint16_t le_conn_interval_min   = hci_subevent_le_remote_connection_parameter_request_get_interval_min(packet);
2721                         uint16_t le_conn_interval_max   = hci_subevent_le_remote_connection_parameter_request_get_interval_max(packet);
2722                         uint16_t le_conn_latency        = hci_subevent_le_remote_connection_parameter_request_get_latency(packet);
2723                         uint16_t le_supervision_timeout = hci_subevent_le_remote_connection_parameter_request_get_timeout(packet);
2724 
2725                         // validate against current connection parameter range
2726                         le_connection_parameter_range_t existing_range;
2727                         gap_get_connection_parameter_range(&existing_range);
2728                         int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout);
2729                         if (update_parameter){
2730                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_REPLY;
2731                             conn->le_conn_interval_min = le_conn_interval_min;
2732                             conn->le_conn_interval_max = le_conn_interval_max;
2733                             conn->le_conn_latency = le_conn_latency;
2734                             conn->le_supervision_timeout = le_supervision_timeout;
2735                         } else {
2736                             conn->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY;
2737                         }
2738                     }
2739                     break;
2740 #ifdef ENABLE_LE_LIMIT_ACL_FRAGMENT_BY_MAX_OCTETS
2741                 case HCI_SUBEVENT_LE_DATA_LENGTH_CHANGE:
2742                     handle = hci_subevent_le_data_length_change_get_connection_handle(packet);
2743                     conn = hci_connection_for_handle(handle);
2744                     if (conn) {
2745                         conn->le_max_tx_octets = hci_subevent_le_data_length_change_get_max_tx_octets(packet);
2746                     }
2747                     break;
2748 #endif
2749                 default:
2750                     break;
2751             }
2752             break;
2753 #endif
2754         case HCI_EVENT_VENDOR_SPECIFIC:
2755             // Vendor specific commands often create vendor specific event instead of num completed packets
2756             // To avoid getting stuck as num_cmds_packets is zero, reset it to 1 for controllers with this behaviour
2757             switch (hci_stack->manufacturer){
2758                 case BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO:
2759                     hci_stack->num_cmd_packets = 1;
2760                     break;
2761                 default:
2762                     break;
2763             }
2764             break;
2765         default:
2766             break;
2767     }
2768 
2769     handle_event_for_current_stack_state(packet, size);
2770 
2771     // notify upper stack
2772 	hci_emit_event(packet, size, 0);   // don't dump, already happened in packet handler
2773 
2774     // moved here to give upper stack a chance to close down everything with hci_connection_t intact
2775     if (hci_event_packet_get_type(packet) == HCI_EVENT_DISCONNECTION_COMPLETE){
2776         if (!packet[2]){
2777             handle = little_endian_read_16(packet, 3);
2778             hci_connection_t * aConn = hci_connection_for_handle(handle);
2779             if (aConn) {
2780                 // discard connection if app did not trigger a reconnect in the event handler
2781                 if (aConn->state == RECEIVED_DISCONNECTION_COMPLETE){
2782                     hci_shutdown_connection(aConn);
2783                 }
2784             }
2785         }
2786     }
2787 
2788 	// execute main loop
2789 	hci_run();
2790 }
2791 
2792 #ifdef ENABLE_CLASSIC
2793 
2794 static void sco_tx_timeout_handler(btstack_timer_source_t * ts);
2795 static void sco_schedule_tx(hci_connection_t * conn);
2796 
2797 static void sco_tx_timeout_handler(btstack_timer_source_t * ts){
2798     log_debug("SCO TX Timeout");
2799     hci_con_handle_t con_handle = (hci_con_handle_t) (uintptr_t) btstack_run_loop_get_timer_context(ts);
2800     hci_connection_t * conn = hci_connection_for_handle(con_handle);
2801     if (!conn) return;
2802 
2803     // trigger send
2804     conn->sco_tx_ready = 1;
2805     // extra packet if CVSD but SCO buffer is too short
2806     if (((hci_stack->sco_voice_setting_active & 0x03) != 0x03) && (hci_stack->sco_data_packet_length < 123)){
2807         conn->sco_tx_ready++;
2808     }
2809     hci_notify_if_sco_can_send_now();
2810 }
2811 
2812 
2813 #define SCO_TX_AFTER_RX_MS (6)
2814 
2815 static void sco_schedule_tx(hci_connection_t * conn){
2816 
2817     uint32_t now = btstack_run_loop_get_time_ms();
2818     uint32_t sco_tx_ms = conn->sco_rx_ms + SCO_TX_AFTER_RX_MS;
2819     int time_delta_ms = sco_tx_ms - now;
2820 
2821     btstack_timer_source_t * timer = (conn->sco_rx_count & 1) ? &conn->timeout : &conn->timeout_sco;
2822 
2823     // log_error("SCO TX at %u in %u", (int) sco_tx_ms, time_delta_ms);
2824     btstack_run_loop_set_timer(timer, time_delta_ms);
2825     btstack_run_loop_set_timer_context(timer, (void *) (uintptr_t) conn->con_handle);
2826     btstack_run_loop_set_timer_handler(timer, &sco_tx_timeout_handler);
2827     btstack_run_loop_add_timer(timer);
2828 }
2829 
2830 static void sco_handler(uint8_t * packet, uint16_t size){
2831     // lookup connection struct
2832     hci_con_handle_t con_handle = READ_SCO_CONNECTION_HANDLE(packet);
2833     hci_connection_t * conn     = hci_connection_for_handle(con_handle);
2834     if (!conn) return;
2835 
2836     // CSR 8811 prefixes 60 byte SCO packet in transparent mode with 20 zero bytes -> skip first 20 payload bytes
2837     if (hci_stack->manufacturer == BLUETOOTH_COMPANY_ID_CAMBRIDGE_SILICON_RADIO){
2838         if ((size == 83) && ((hci_stack->sco_voice_setting_active & 0x03) == 0x03)){
2839             packet[2] = 0x3c;
2840             memmove(&packet[3], &packet[23], 63);
2841             size = 63;
2842         }
2843     }
2844 
2845     if (hci_have_usb_transport()){
2846         // Nothing to do
2847     } else {
2848         // 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);
2849         if (hci_stack->synchronous_flow_control_enabled == 0){
2850             uint32_t now = btstack_run_loop_get_time_ms();
2851 
2852             if (!conn->sco_rx_valid){
2853                 // ignore first 10 packets
2854                 conn->sco_rx_count++;
2855                 // log_debug("sco rx count %u", conn->sco_rx_count);
2856                 if (conn->sco_rx_count == 10) {
2857                     // use first timestamp as is and pretent it just started
2858                     conn->sco_rx_ms = now;
2859                     conn->sco_rx_valid = 1;
2860                     conn->sco_rx_count = 0;
2861                     sco_schedule_tx(conn);
2862                 }
2863             } else {
2864                 // track expected arrival timme
2865                 conn->sco_rx_count++;
2866                 conn->sco_rx_ms += 7;
2867                 int delta = (int32_t) (now - conn->sco_rx_ms);
2868                 if (delta > 0){
2869                     conn->sco_rx_ms++;
2870                 }
2871                 // log_debug("sco rx %u", conn->sco_rx_ms);
2872                 sco_schedule_tx(conn);
2873             }
2874         }
2875     }
2876     // deliver to app
2877     if (hci_stack->sco_packet_handler) {
2878         hci_stack->sco_packet_handler(HCI_SCO_DATA_PACKET, 0, packet, size);
2879     }
2880 
2881 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
2882     conn->num_packets_completed++;
2883     hci_stack->host_completed_packets = 1;
2884     hci_run();
2885 #endif
2886 }
2887 #endif
2888 
2889 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
2890     hci_dump_packet(packet_type, 1, packet, size);
2891     switch (packet_type) {
2892         case HCI_EVENT_PACKET:
2893             event_handler(packet, size);
2894             break;
2895         case HCI_ACL_DATA_PACKET:
2896             acl_handler(packet, size);
2897             break;
2898 #ifdef ENABLE_CLASSIC
2899         case HCI_SCO_DATA_PACKET:
2900             sco_handler(packet, size);
2901             break;
2902 #endif
2903         default:
2904             break;
2905     }
2906 }
2907 
2908 /**
2909  * @brief Add event packet handler.
2910  */
2911 void hci_add_event_handler(btstack_packet_callback_registration_t * callback_handler){
2912     btstack_linked_list_add_tail(&hci_stack->event_handlers, (btstack_linked_item_t*) callback_handler);
2913 }
2914 
2915 
2916 /** Register HCI packet handlers */
2917 void hci_register_acl_packet_handler(btstack_packet_handler_t handler){
2918     hci_stack->acl_packet_handler = handler;
2919 }
2920 
2921 #ifdef ENABLE_CLASSIC
2922 /**
2923  * @brief Registers a packet handler for SCO data. Used for HSP and HFP profiles.
2924  */
2925 void hci_register_sco_packet_handler(btstack_packet_handler_t handler){
2926     hci_stack->sco_packet_handler = handler;
2927 }
2928 #endif
2929 
2930 static void hci_state_reset(void){
2931     // no connections yet
2932     hci_stack->connections = NULL;
2933 
2934     // keep discoverable/connectable as this has been requested by the client(s)
2935     // hci_stack->discoverable = 0;
2936     // hci_stack->connectable = 0;
2937     // hci_stack->bondable = 1;
2938     // hci_stack->own_addr_type = 0;
2939 
2940     // buffer is free
2941     hci_stack->hci_packet_buffer_reserved = 0;
2942 
2943     // no pending cmds
2944     hci_stack->decline_reason = 0;
2945     hci_stack->new_scan_enable_value = 0xff;
2946 
2947     // LE
2948 #ifdef ENABLE_BLE
2949     memset(hci_stack->le_random_address, 0, 6);
2950     hci_stack->le_random_address_set = 0;
2951 #endif
2952 #ifdef ENABLE_LE_CENTRAL
2953     hci_stack->le_scanning_active  = 0;
2954     hci_stack->le_scan_type = 0xff;
2955     hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
2956     hci_stack->le_whitelist = 0;
2957     hci_stack->le_whitelist_capacity = 0;
2958 #endif
2959 }
2960 
2961 #ifdef ENABLE_CLASSIC
2962 /**
2963  * @brief Configure Bluetooth hardware control. Has to be called before power on.
2964  */
2965 void hci_set_link_key_db(btstack_link_key_db_t const * link_key_db){
2966     // store and open remote device db
2967     hci_stack->link_key_db = link_key_db;
2968     if (hci_stack->link_key_db) {
2969         hci_stack->link_key_db->open();
2970     }
2971 }
2972 #endif
2973 
2974 void hci_init(const hci_transport_t *transport, const void *config){
2975 
2976 #ifdef HAVE_MALLOC
2977     if (!hci_stack) {
2978         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
2979     }
2980 #else
2981     hci_stack = &hci_stack_static;
2982 #endif
2983     memset(hci_stack, 0, sizeof(hci_stack_t));
2984 
2985     // reference to use transport layer implementation
2986     hci_stack->hci_transport = transport;
2987 
2988     // reference to used config
2989     hci_stack->config = config;
2990 
2991     // setup pointer for outgoing packet buffer
2992     hci_stack->hci_packet_buffer = &hci_stack->hci_packet_buffer_data[HCI_OUTGOING_PRE_BUFFER_SIZE];
2993 
2994     // max acl payload size defined in config.h
2995     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
2996 
2997     // register packet handlers with transport
2998     transport->register_packet_handler(&packet_handler);
2999 
3000     hci_stack->state = HCI_STATE_OFF;
3001 
3002     // class of device
3003     hci_stack->class_of_device = 0x007a020c; // Smartphone
3004 
3005     // bondable by default
3006     hci_stack->bondable = 1;
3007 
3008 #ifdef ENABLE_CLASSIC
3009     // classic name
3010     hci_stack->local_name = default_classic_name;
3011 
3012     // Master slave policy
3013     hci_stack->master_slave_policy = 1;
3014 
3015     // Allow Role Switch
3016     hci_stack->allow_role_switch = 1;
3017 
3018     // Default / minimum security level = 2
3019     hci_stack->gap_security_level = LEVEL_2;
3020 
3021     // Errata-11838 mandates 7 bytes for GAP Security Level 1-3
3022     hci_stack->gap_required_encyrption_key_size = 7;
3023 #endif
3024 
3025     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
3026     hci_stack->ssp_enable = 1;
3027     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
3028     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
3029     hci_stack->ssp_auto_accept = 1;
3030 
3031     // Secure Connections: enable (requires support from Controller)
3032     hci_stack->secure_connections_enable = true;
3033 
3034     // voice setting - signed 16 bit pcm data with CVSD over the air
3035     hci_stack->sco_voice_setting = 0x60;
3036 
3037 #ifdef ENABLE_LE_CENTRAL
3038     // connection parameter to use for outgoing connections
3039     hci_stack->le_connection_scan_interval = 0x0060;   // 60ms
3040     hci_stack->le_connection_scan_window  = 0x0030;    // 30ms
3041     hci_stack->le_connection_interval_min = 0x0008;    // 10 ms
3042     hci_stack->le_connection_interval_max = 0x0018;    // 30 ms
3043     hci_stack->le_connection_latency      = 4;         // 4
3044     hci_stack->le_supervision_timeout     = 0x0048;    // 720 ms
3045     hci_stack->le_minimum_ce_length       = 2;         // 1.25 ms
3046     hci_stack->le_maximum_ce_length       = 0x0030;    // 30 ms
3047 
3048     // default LE Scanning
3049     hci_stack->le_scan_interval = 0x1e0;
3050     hci_stack->le_scan_window   =  0x30;
3051 #endif
3052 
3053 #ifdef ENABLE_LE_PERIPHERAL
3054     hci_stack->le_max_number_peripheral_connections = 1; // only single connection as peripheral
3055 #endif
3056 
3057     // connection parameter range used to answer connection parameter update requests in l2cap
3058     hci_stack->le_connection_parameter_range.le_conn_interval_min =          6;
3059     hci_stack->le_connection_parameter_range.le_conn_interval_max =       3200;
3060     hci_stack->le_connection_parameter_range.le_conn_latency_min =           0;
3061     hci_stack->le_connection_parameter_range.le_conn_latency_max =         500;
3062     hci_stack->le_connection_parameter_range.le_supervision_timeout_min =   10;
3063     hci_stack->le_connection_parameter_range.le_supervision_timeout_max = 3200;
3064 
3065     hci_state_reset();
3066 }
3067 
3068 /**
3069  * @brief Configure Bluetooth chipset driver. Has to be called before power on, or right after receiving the local version information
3070  */
3071 void hci_set_chipset(const btstack_chipset_t *chipset_driver){
3072     hci_stack->chipset = chipset_driver;
3073 
3074     // reset chipset driver - init is also called on power_up
3075     if (hci_stack->chipset && hci_stack->chipset->init){
3076         hci_stack->chipset->init(hci_stack->config);
3077     }
3078 }
3079 
3080 /**
3081  * @brief Configure Bluetooth hardware control. Has to be called after hci_init() but before power on.
3082  */
3083 void hci_set_control(const btstack_control_t *hardware_control){
3084     // references to used control implementation
3085     hci_stack->control = hardware_control;
3086     // init with transport config
3087     hardware_control->init(hci_stack->config);
3088 }
3089 
3090 void hci_close(void){
3091     // close remote device db
3092     if (hci_stack->link_key_db) {
3093         hci_stack->link_key_db->close();
3094     }
3095 
3096     btstack_linked_list_iterator_t lit;
3097     btstack_linked_list_iterator_init(&lit, &hci_stack->connections);
3098     while (btstack_linked_list_iterator_has_next(&lit)){
3099         // cancel all l2cap connections by emitting dicsconnection complete before shutdown (free) connection
3100         hci_connection_t * connection = (hci_connection_t*) btstack_linked_list_iterator_next(&lit);
3101         hci_emit_disconnection_complete(connection->con_handle, 0x16); // terminated by local host
3102         hci_shutdown_connection(connection);
3103     }
3104 
3105     hci_power_control(HCI_POWER_OFF);
3106 
3107 #ifdef HAVE_MALLOC
3108     free(hci_stack);
3109 #endif
3110     hci_stack = NULL;
3111 }
3112 
3113 #ifdef ENABLE_CLASSIC
3114 void gap_set_required_encryption_key_size(uint8_t encryption_key_size){
3115     // validate ranage and set
3116     if (encryption_key_size < 7)  return;
3117     if (encryption_key_size > 16) return;
3118     hci_stack->gap_required_encyrption_key_size = encryption_key_size;
3119 }
3120 
3121 void gap_set_security_level(gap_security_level_t security_level){
3122     hci_stack->gap_security_level = security_level;
3123 }
3124 
3125 gap_security_level_t gap_get_security_level(void){
3126     return hci_stack->gap_security_level;
3127 }
3128 #endif
3129 
3130 #ifdef ENABLE_CLASSIC
3131 void gap_set_class_of_device(uint32_t class_of_device){
3132     hci_stack->class_of_device = class_of_device;
3133 }
3134 
3135 void gap_set_default_link_policy_settings(uint16_t default_link_policy_settings){
3136     hci_stack->default_link_policy_settings = default_link_policy_settings;
3137 }
3138 
3139 void gap_set_allow_role_switch(bool allow_role_switch){
3140     hci_stack->allow_role_switch = allow_role_switch ? 1 : 0;
3141 }
3142 
3143 uint8_t hci_get_allow_role_switch(void){
3144     return  hci_stack->allow_role_switch;
3145 }
3146 
3147 void gap_set_link_supervision_timeout(uint16_t link_supervision_timeout){
3148     hci_stack->link_supervision_timeout = link_supervision_timeout;
3149 }
3150 
3151 void hci_disable_l2cap_timeout_check(void){
3152     disable_l2cap_timeouts = 1;
3153 }
3154 #endif
3155 
3156 #if !defined(HAVE_PLATFORM_IPHONE_OS) && !defined (HAVE_HOST_CONTROLLER_API)
3157 // Set Public BD ADDR - passed on to Bluetooth chipset if supported in bt_control_h
3158 void hci_set_bd_addr(bd_addr_t addr){
3159     (void)memcpy(hci_stack->custom_bd_addr, addr, 6);
3160     hci_stack->custom_bd_addr_set = 1;
3161 }
3162 #endif
3163 
3164 // State-Module-Driver overview
3165 // state                    module  low-level
3166 // HCI_STATE_OFF             off      close
3167 // HCI_STATE_INITIALIZING,   on       open
3168 // HCI_STATE_WORKING,        on       open
3169 // HCI_STATE_HALTING,        on       open
3170 // HCI_STATE_SLEEPING,    off/sleep   close
3171 // HCI_STATE_FALLING_ASLEEP  on       open
3172 
3173 static int hci_power_control_on(void){
3174 
3175     // power on
3176     int err = 0;
3177     if (hci_stack->control && hci_stack->control->on){
3178         err = (*hci_stack->control->on)();
3179     }
3180     if (err){
3181         log_error( "POWER_ON failed");
3182         hci_emit_hci_open_failed();
3183         return err;
3184     }
3185 
3186     // int chipset driver
3187     if (hci_stack->chipset && hci_stack->chipset->init){
3188         hci_stack->chipset->init(hci_stack->config);
3189     }
3190 
3191     // init transport
3192     if (hci_stack->hci_transport->init){
3193         hci_stack->hci_transport->init(hci_stack->config);
3194     }
3195 
3196     // open transport
3197     err = hci_stack->hci_transport->open();
3198     if (err){
3199         log_error( "HCI_INIT failed, turning Bluetooth off again");
3200         if (hci_stack->control && hci_stack->control->off){
3201             (*hci_stack->control->off)();
3202         }
3203         hci_emit_hci_open_failed();
3204         return err;
3205     }
3206     return 0;
3207 }
3208 
3209 static void hci_power_control_off(void){
3210 
3211     log_info("hci_power_control_off");
3212 
3213     // close low-level device
3214     hci_stack->hci_transport->close();
3215 
3216     log_info("hci_power_control_off - hci_transport closed");
3217 
3218     // power off
3219     if (hci_stack->control && hci_stack->control->off){
3220         (*hci_stack->control->off)();
3221     }
3222 
3223     log_info("hci_power_control_off - control closed");
3224 
3225     hci_stack->state = HCI_STATE_OFF;
3226 }
3227 
3228 static void hci_power_control_sleep(void){
3229 
3230     log_info("hci_power_control_sleep");
3231 
3232 #if 0
3233     // don't close serial port during sleep
3234 
3235     // close low-level device
3236     hci_stack->hci_transport->close(hci_stack->config);
3237 #endif
3238 
3239     // sleep mode
3240     if (hci_stack->control && hci_stack->control->sleep){
3241         (*hci_stack->control->sleep)();
3242     }
3243 
3244     hci_stack->state = HCI_STATE_SLEEPING;
3245 }
3246 
3247 static int hci_power_control_wake(void){
3248 
3249     log_info("hci_power_control_wake");
3250 
3251     // wake on
3252     if (hci_stack->control && hci_stack->control->wake){
3253         (*hci_stack->control->wake)();
3254     }
3255 
3256 #if 0
3257     // open low-level device
3258     int err = hci_stack->hci_transport->open(hci_stack->config);
3259     if (err){
3260         log_error( "HCI_INIT failed, turning Bluetooth off again");
3261         if (hci_stack->control && hci_stack->control->off){
3262             (*hci_stack->control->off)();
3263         }
3264         hci_emit_hci_open_failed();
3265         return err;
3266     }
3267 #endif
3268 
3269     return 0;
3270 }
3271 
3272 static void hci_power_transition_to_initializing(void){
3273     // set up state machine
3274     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
3275     hci_stack->hci_packet_buffer_reserved = 0;
3276     hci_stack->state = HCI_STATE_INITIALIZING;
3277     hci_stack->substate = HCI_INIT_SEND_RESET;
3278 }
3279 
3280 int hci_power_control(HCI_POWER_MODE power_mode){
3281 
3282     log_info("hci_power_control: %d, current mode %u", power_mode, hci_stack->state);
3283 
3284     int err = 0;
3285     switch (hci_stack->state){
3286 
3287         case HCI_STATE_OFF:
3288             switch (power_mode){
3289                 case HCI_POWER_ON:
3290                     err = hci_power_control_on();
3291                     if (err) {
3292                         log_error("hci_power_control_on() error %d", err);
3293                         return err;
3294                     }
3295                     hci_power_transition_to_initializing();
3296                     break;
3297                 case HCI_POWER_OFF:
3298                     // do nothing
3299                     break;
3300                 case HCI_POWER_SLEEP:
3301                     // do nothing (with SLEEP == OFF)
3302                     break;
3303             }
3304             break;
3305 
3306         case HCI_STATE_INITIALIZING:
3307             switch (power_mode){
3308                 case HCI_POWER_ON:
3309                     // do nothing
3310                     break;
3311                 case HCI_POWER_OFF:
3312                     // no connections yet, just turn it off
3313                     hci_power_control_off();
3314                     break;
3315                 case HCI_POWER_SLEEP:
3316                     // no connections yet, just turn it off
3317                     hci_power_control_sleep();
3318                     break;
3319             }
3320             break;
3321 
3322         case HCI_STATE_WORKING:
3323             switch (power_mode){
3324                 case HCI_POWER_ON:
3325                     // do nothing
3326                     break;
3327                 case HCI_POWER_OFF:
3328                     // see hci_run
3329                     hci_stack->state = HCI_STATE_HALTING;
3330                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3331                     break;
3332                 case HCI_POWER_SLEEP:
3333                     // see hci_run
3334                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3335                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3336                     break;
3337             }
3338             break;
3339 
3340         case HCI_STATE_HALTING:
3341             switch (power_mode){
3342                 case HCI_POWER_ON:
3343                     hci_power_transition_to_initializing();
3344                     break;
3345                 case HCI_POWER_OFF:
3346                     // do nothing
3347                     break;
3348                 case HCI_POWER_SLEEP:
3349                     // see hci_run
3350                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
3351                     hci_stack->substate = HCI_FALLING_ASLEEP_DISCONNECT;
3352                     break;
3353             }
3354             break;
3355 
3356         case HCI_STATE_FALLING_ASLEEP:
3357             switch (power_mode){
3358                 case HCI_POWER_ON:
3359 
3360 #ifdef HAVE_PLATFORM_IPHONE_OS
3361                     // nothing to do, if H4 supports power management
3362                     if (btstack_control_iphone_power_management_enabled()){
3363                         hci_stack->state = HCI_STATE_INITIALIZING;
3364                         hci_stack->substate = HCI_INIT_WRITE_SCAN_ENABLE;   // init after sleep
3365                         break;
3366                     }
3367 #endif
3368                     hci_power_transition_to_initializing();
3369                     break;
3370                 case HCI_POWER_OFF:
3371                     // see hci_run
3372                     hci_stack->state = HCI_STATE_HALTING;
3373                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3374                     break;
3375                 case HCI_POWER_SLEEP:
3376                     // do nothing
3377                     break;
3378             }
3379             break;
3380 
3381         case HCI_STATE_SLEEPING:
3382             switch (power_mode){
3383                 case HCI_POWER_ON:
3384 
3385 #ifdef HAVE_PLATFORM_IPHONE_OS
3386                     // nothing to do, if H4 supports power management
3387                     if (btstack_control_iphone_power_management_enabled()){
3388                         hci_stack->state = HCI_STATE_INITIALIZING;
3389                         hci_stack->substate = HCI_INIT_AFTER_SLEEP;
3390                         hci_update_scan_enable();
3391                         break;
3392                     }
3393 #endif
3394                     err = hci_power_control_wake();
3395                     if (err) return err;
3396                     hci_power_transition_to_initializing();
3397                     break;
3398                 case HCI_POWER_OFF:
3399                     hci_stack->state = HCI_STATE_HALTING;
3400                     hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_NO_TIMER;
3401                     break;
3402                 case HCI_POWER_SLEEP:
3403                     // do nothing
3404                     break;
3405             }
3406             break;
3407     }
3408 
3409     // create internal event
3410 	hci_emit_state();
3411 
3412 	// trigger next/first action
3413 	hci_run();
3414 
3415     return 0;
3416 }
3417 
3418 
3419 #ifdef ENABLE_CLASSIC
3420 
3421 static void hci_update_scan_enable(void){
3422     // 2 = page scan, 1 = inq scan
3423     hci_stack->new_scan_enable_value  = (hci_stack->connectable << 1) | hci_stack->discoverable;
3424     hci_run();
3425 }
3426 
3427 void gap_discoverable_control(uint8_t enable){
3428     if (enable) enable = 1; // normalize argument
3429 
3430     if (hci_stack->discoverable == enable){
3431         hci_emit_discoverable_enabled(hci_stack->discoverable);
3432         return;
3433     }
3434 
3435     hci_stack->discoverable = enable;
3436     hci_update_scan_enable();
3437 }
3438 
3439 void gap_connectable_control(uint8_t enable){
3440     if (enable) enable = 1; // normalize argument
3441 
3442     // don't emit event
3443     if (hci_stack->connectable == enable) return;
3444 
3445     hci_stack->connectable = enable;
3446     hci_update_scan_enable();
3447 }
3448 #endif
3449 
3450 void gap_local_bd_addr(bd_addr_t address_buffer){
3451     (void)memcpy(address_buffer, hci_stack->local_bd_addr, 6);
3452 }
3453 
3454 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
3455 static void hci_host_num_completed_packets(void){
3456 
3457     // create packet manually as arrays are not supported and num_commands should not get reduced
3458     hci_reserve_packet_buffer();
3459     uint8_t * packet = hci_get_outgoing_packet_buffer();
3460 
3461     uint16_t size = 0;
3462     uint16_t num_handles = 0;
3463     packet[size++] = 0x35;
3464     packet[size++] = 0x0c;
3465     size++;  // skip param len
3466     size++;  // skip num handles
3467 
3468     // add { handle, packets } entries
3469     btstack_linked_item_t * it;
3470     for (it = (btstack_linked_item_t *) hci_stack->connections; it ; it = it->next){
3471         hci_connection_t * connection = (hci_connection_t *) it;
3472         if (connection->num_packets_completed){
3473             little_endian_store_16(packet, size, connection->con_handle);
3474             size += 2;
3475             little_endian_store_16(packet, size, connection->num_packets_completed);
3476             size += 2;
3477             //
3478             num_handles++;
3479             connection->num_packets_completed = 0;
3480         }
3481     }
3482 
3483     packet[2] = size - 3;
3484     packet[3] = num_handles;
3485 
3486     hci_stack->host_completed_packets = 0;
3487 
3488     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
3489     hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
3490 
3491     // release packet buffer for synchronous transport implementations
3492     if (hci_transport_synchronous()){
3493         hci_release_packet_buffer();
3494         hci_emit_transport_packet_sent();
3495     }
3496 }
3497 #endif
3498 
3499 static void hci_halting_timeout_handler(btstack_timer_source_t * ds){
3500     UNUSED(ds);
3501     hci_stack->substate = HCI_HALTING_CLOSE;
3502     // allow packet handlers to defer final shutdown
3503     hci_emit_state();
3504     hci_run();
3505 }
3506 
3507 static bool hci_run_acl_fragments(void){
3508     if (hci_stack->acl_fragmentation_total_size > 0) {
3509         hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(hci_stack->hci_packet_buffer);
3510         hci_connection_t *connection = hci_connection_for_handle(con_handle);
3511         if (connection) {
3512             if (hci_can_send_prepared_acl_packet_now(con_handle)){
3513                 hci_send_acl_packet_fragments(connection);
3514                 return true;
3515             }
3516         } else {
3517             // connection gone -> discard further fragments
3518             log_info("hci_run: fragmented ACL packet no connection -> discard fragment");
3519             hci_stack->acl_fragmentation_total_size = 0;
3520             hci_stack->acl_fragmentation_pos = 0;
3521         }
3522     }
3523     return false;
3524 }
3525 
3526 #ifdef ENABLE_CLASSIC
3527 static bool hci_run_general_gap_classic(void){
3528 
3529     // decline incoming connections
3530     if (hci_stack->decline_reason){
3531         uint8_t reason = hci_stack->decline_reason;
3532         hci_stack->decline_reason = 0;
3533         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
3534         return true;
3535     }
3536     // send scan enable
3537     if ((hci_stack->state == HCI_STATE_WORKING) && (hci_stack->new_scan_enable_value != 0xff) && hci_classic_supported()){
3538         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
3539         hci_stack->new_scan_enable_value = 0xff;
3540         return true;
3541     }
3542     // start/stop inquiry
3543     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)){
3544         uint8_t duration = hci_stack->inquiry_state;
3545         hci_stack->inquiry_state = GAP_INQUIRY_STATE_ACTIVE;
3546         hci_send_cmd(&hci_inquiry, GAP_IAC_GENERAL_INQUIRY, duration, 0);
3547         return true;
3548     }
3549     if (hci_stack->inquiry_state == GAP_INQUIRY_STATE_W2_CANCEL){
3550         hci_stack->inquiry_state = GAP_INQUIRY_STATE_W4_CANCELLED;
3551         hci_send_cmd(&hci_inquiry_cancel);
3552         return true;
3553     }
3554     // remote name request
3555     if (hci_stack->remote_name_state == GAP_REMOTE_NAME_STATE_W2_SEND){
3556         hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W4_COMPLETE;
3557         hci_send_cmd(&hci_remote_name_request, hci_stack->remote_name_addr,
3558                      hci_stack->remote_name_page_scan_repetition_mode, 0, hci_stack->remote_name_clock_offset);
3559         return true;
3560     }
3561     // pairing
3562     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE){
3563         uint8_t state = hci_stack->gap_pairing_state;
3564         hci_stack->gap_pairing_state = GAP_PAIRING_STATE_IDLE;
3565         switch (state){
3566             case GAP_PAIRING_STATE_SEND_PIN:
3567                 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);
3568                 break;
3569             case GAP_PAIRING_STATE_SEND_PIN_NEGATIVE:
3570                 hci_send_cmd(&hci_pin_code_request_negative_reply, hci_stack->gap_pairing_addr);
3571                 break;
3572             case GAP_PAIRING_STATE_SEND_PASSKEY:
3573                 hci_send_cmd(&hci_user_passkey_request_reply, hci_stack->gap_pairing_addr, hci_stack->gap_pairing_input.gap_pairing_passkey);
3574                 break;
3575             case GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE:
3576                 hci_send_cmd(&hci_user_passkey_request_negative_reply, hci_stack->gap_pairing_addr);
3577                 break;
3578             case GAP_PAIRING_STATE_SEND_CONFIRMATION:
3579                 hci_send_cmd(&hci_user_confirmation_request_reply, hci_stack->gap_pairing_addr);
3580                 break;
3581             case GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE:
3582                 hci_send_cmd(&hci_user_confirmation_request_negative_reply, hci_stack->gap_pairing_addr);
3583                 break;
3584             default:
3585                 break;
3586         }
3587         return true;
3588     }
3589     return false;
3590 }
3591 #endif
3592 
3593 #ifdef ENABLE_BLE
3594 static bool hci_run_general_gap_le(void){
3595 
3596     // advertisements, active scanning, and creating connections requires random address to be set if using private address
3597 
3598     if (hci_stack->state != HCI_STATE_WORKING) return false;
3599     if ( (hci_stack->le_own_addr_type != BD_ADDR_TYPE_LE_PUBLIC) && (hci_stack->le_random_address_set == 0) ) return false;
3600 
3601 #ifdef ENABLE_LE_CENTRAL
3602     // parameter change requires scanning to be stopped first
3603     if (hci_stack->le_scan_type != 0xff) {
3604         if (hci_stack->le_scanning_active){
3605             hci_stack->le_scanning_active = 0;
3606             hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
3607         } else {
3608             int scan_type = (int) hci_stack->le_scan_type;
3609             hci_stack->le_scan_type = 0xff;
3610             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);
3611         }
3612         return true;
3613     }
3614     // finally, we can enable/disable le scan
3615     if ((hci_stack->le_scanning_enabled != hci_stack->le_scanning_active)){
3616         hci_stack->le_scanning_active = hci_stack->le_scanning_enabled;
3617         hci_send_cmd(&hci_le_set_scan_enable, hci_stack->le_scanning_enabled, 0);
3618         return true;
3619     }
3620 #endif
3621 #ifdef ENABLE_LE_PERIPHERAL
3622     // le advertisement control
3623     if (hci_stack->le_advertisements_todo){
3624         log_info("hci_run: gap_le: adv todo: %x", hci_stack->le_advertisements_todo );
3625     }
3626     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_DISABLE){
3627         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_DISABLE;
3628         hci_send_cmd(&hci_le_set_advertise_enable, 0);
3629         return true;
3630     }
3631     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_PARAMS){
3632         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_PARAMS;
3633         hci_send_cmd(&hci_le_set_advertising_parameters,
3634                      hci_stack->le_advertisements_interval_min,
3635                      hci_stack->le_advertisements_interval_max,
3636                      hci_stack->le_advertisements_type,
3637                      hci_stack->le_own_addr_type,
3638                      hci_stack->le_advertisements_direct_address_type,
3639                      hci_stack->le_advertisements_direct_address,
3640                      hci_stack->le_advertisements_channel_map,
3641                      hci_stack->le_advertisements_filter_policy);
3642         return true;
3643     }
3644     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_ADV_DATA){
3645         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
3646         uint8_t adv_data_clean[31];
3647         memset(adv_data_clean, 0, sizeof(adv_data_clean));
3648         (void)memcpy(adv_data_clean, hci_stack->le_advertisements_data,
3649                      hci_stack->le_advertisements_data_len);
3650         btstack_replace_bd_addr_placeholder(adv_data_clean, hci_stack->le_advertisements_data_len, hci_stack->local_bd_addr);
3651         hci_send_cmd(&hci_le_set_advertising_data, hci_stack->le_advertisements_data_len, adv_data_clean);
3652         return true;
3653     }
3654     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA){
3655         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
3656         uint8_t scan_data_clean[31];
3657         memset(scan_data_clean, 0, sizeof(scan_data_clean));
3658         (void)memcpy(scan_data_clean, hci_stack->le_scan_response_data,
3659                      hci_stack->le_scan_response_data_len);
3660         btstack_replace_bd_addr_placeholder(scan_data_clean, hci_stack->le_scan_response_data_len, hci_stack->local_bd_addr);
3661         hci_send_cmd(&hci_le_set_scan_response_data, hci_stack->le_scan_response_data_len, scan_data_clean);
3662         return true;
3663     }
3664     if (hci_stack->le_advertisements_todo & LE_ADVERTISEMENT_TASKS_ENABLE){
3665         hci_stack->le_advertisements_todo &= ~LE_ADVERTISEMENT_TASKS_ENABLE;
3666         hci_send_cmd(&hci_le_set_advertise_enable, 1);
3667         return true;
3668     }
3669 #endif
3670 
3671 #ifdef ENABLE_LE_CENTRAL
3672     //
3673     // LE Whitelist Management
3674     //
3675 
3676     // check if whitelist needs modification
3677     btstack_linked_list_iterator_t lit;
3678     int modification_pending = 0;
3679     btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3680     while (btstack_linked_list_iterator_has_next(&lit)){
3681         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3682         if (entry->state & (LE_WHITELIST_REMOVE_FROM_CONTROLLER | LE_WHITELIST_ADD_TO_CONTROLLER)){
3683             modification_pending = 1;
3684             break;
3685         }
3686     }
3687 
3688     if (modification_pending){
3689         // stop connnecting if modification pending
3690         if (hci_stack->le_connecting_state != LE_CONNECTING_IDLE){
3691             hci_send_cmd(&hci_le_create_connection_cancel);
3692             return true;
3693         }
3694 
3695         // add/remove entries
3696         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
3697         while (btstack_linked_list_iterator_has_next(&lit)){
3698             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
3699             if (entry->state & LE_WHITELIST_ADD_TO_CONTROLLER){
3700                 entry->state = LE_WHITELIST_ON_CONTROLLER;
3701                 hci_send_cmd(&hci_le_add_device_to_white_list, entry->address_type, entry->address);
3702                 return true;
3703             }
3704             if (entry->state & LE_WHITELIST_REMOVE_FROM_CONTROLLER){
3705                 bd_addr_t address;
3706                 bd_addr_type_t address_type = entry->address_type;
3707                 (void)memcpy(address, entry->address, 6);
3708                 btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
3709                 btstack_memory_whitelist_entry_free(entry);
3710                 hci_send_cmd(&hci_le_remove_device_from_white_list, address_type, address);
3711                 return true;
3712             }
3713         }
3714     }
3715 
3716     // start connecting
3717     if ( (hci_stack->le_connecting_state == LE_CONNECTING_IDLE) &&
3718          !btstack_linked_list_empty(&hci_stack->le_whitelist)){
3719         bd_addr_t null_addr;
3720         memset(null_addr, 0, 6);
3721         hci_send_cmd(&hci_le_create_connection,
3722                      hci_stack->le_connection_scan_interval,    // scan interval: 60 ms
3723                      hci_stack->le_connection_scan_window,    // scan interval: 30 ms
3724                      1,         // use whitelist
3725                      0,         // peer address type
3726                      null_addr, // peer bd addr
3727                      hci_stack->le_own_addr_type, // our addr type:
3728                      hci_stack->le_connection_interval_min,    // conn interval min
3729                      hci_stack->le_connection_interval_max,    // conn interval max
3730                      hci_stack->le_connection_latency,         // conn latency
3731                      hci_stack->le_supervision_timeout,        // conn latency
3732                      hci_stack->le_minimum_ce_length,          // min ce length
3733                      hci_stack->le_maximum_ce_length           // max ce length
3734         );
3735         return true;
3736     }
3737 #endif
3738     return false;
3739 }
3740 #endif
3741 
3742 static bool hci_run_general_pending_commmands(void){
3743     btstack_linked_item_t * it;
3744     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
3745         hci_connection_t * connection = (hci_connection_t *) it;
3746 
3747         switch(connection->state){
3748             case SEND_CREATE_CONNECTION:
3749                 switch(connection->address_type){
3750 #ifdef ENABLE_CLASSIC
3751                     case BD_ADDR_TYPE_ACL:
3752                         log_info("sending hci_create_connection");
3753                         hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_stack->allow_role_switch);
3754                         break;
3755 #endif
3756                     default:
3757 #ifdef ENABLE_BLE
3758 #ifdef ENABLE_LE_CENTRAL
3759                         // track outgoing connection
3760                         hci_stack->outgoing_addr_type = connection->address_type;
3761                         (void)memcpy(hci_stack->outgoing_addr,
3762                                      connection->address, 6);
3763                         log_info("sending hci_le_create_connection");
3764                         hci_send_cmd(&hci_le_create_connection,
3765                                      hci_stack->le_connection_scan_interval,    // conn scan interval
3766                                      hci_stack->le_connection_scan_window,      // conn scan windows
3767                                      0,         // don't use whitelist
3768                                      connection->address_type, // peer address type
3769                                      connection->address,      // peer bd addr
3770                                      hci_stack->le_own_addr_type, // our addr type:
3771                                      hci_stack->le_connection_interval_min,    // conn interval min
3772                                      hci_stack->le_connection_interval_max,    // conn interval max
3773                                      hci_stack->le_connection_latency,         // conn latency
3774                                      hci_stack->le_supervision_timeout,        // conn latency
3775                                      hci_stack->le_minimum_ce_length,          // min ce length
3776                                      hci_stack->le_maximum_ce_length          // max ce length
3777                         );
3778                         connection->state = SENT_CREATE_CONNECTION;
3779 #endif
3780 #endif
3781                         break;
3782                 }
3783                 return true;
3784 
3785 #ifdef ENABLE_CLASSIC
3786             case RECEIVED_CONNECTION_REQUEST:
3787                 connection->role  = HCI_ROLE_SLAVE;
3788                 if (connection->address_type == BD_ADDR_TYPE_ACL){
3789                     log_info("sending hci_accept_connection_request");
3790                     connection->state = ACCEPTED_CONNECTION_REQUEST;
3791                     hci_send_cmd(&hci_accept_connection_request, connection->address, hci_stack->master_slave_policy);
3792                 }
3793                 return true;
3794 #endif
3795 
3796 #ifdef ENABLE_BLE
3797 #ifdef ENABLE_LE_CENTRAL
3798             case SEND_CANCEL_CONNECTION:
3799                 connection->state = SENT_CANCEL_CONNECTION;
3800                 hci_send_cmd(&hci_le_create_connection_cancel);
3801                 return true;
3802 #endif
3803 #endif
3804             case SEND_DISCONNECT:
3805                 connection->state = SENT_DISCONNECT;
3806                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3807                 return true;
3808 
3809             default:
3810                 break;
3811         }
3812 
3813         // no further commands if connection is about to get shut down
3814         if (connection->state == SENT_DISCONNECT) continue;
3815 
3816         if (connection->authentication_flags & READ_RSSI){
3817             connectionClearAuthenticationFlags(connection, READ_RSSI);
3818             hci_send_cmd(&hci_read_rssi, connection->con_handle);
3819             return true;
3820         }
3821 
3822 #ifdef ENABLE_CLASSIC
3823 
3824         if (connection->authentication_flags & WRITE_SUPERVISION_TIMEOUT){
3825             connectionClearAuthenticationFlags(connection, WRITE_SUPERVISION_TIMEOUT);
3826             hci_send_cmd(&hci_write_link_supervision_timeout, connection->con_handle, hci_stack->link_supervision_timeout);
3827             return true;
3828         }
3829 
3830         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
3831             log_info("responding to link key request");
3832             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
3833 
3834             link_key_t link_key;
3835             link_key_type_t link_key_type;
3836             bool have_link_key = hci_stack->link_key_db && hci_stack->link_key_db->get_link_key(connection->address, link_key, &link_key_type);
3837 
3838             const uint16_t sc_enabled_mask = BONDING_REMOTE_SUPPORTS_SC_HOST | BONDING_REMOTE_SUPPORTS_SC_CONTROLLER;
3839             bool sc_enabled_remote = (connection->bonding_flags & sc_enabled_mask) == sc_enabled_mask;
3840             bool sc_downgrade = have_link_key && (gap_secure_connection_for_link_key_type(link_key_type) == 1) && !sc_enabled_remote;
3841             if (sc_downgrade){
3842                 log_info("Link key based on SC, but remote does not support SC -> disconnect");
3843                 connection->state = SENT_DISCONNECT;
3844                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3845                 return true;
3846             }
3847 
3848             bool security_level_sufficient = have_link_key && (gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level);
3849             if (have_link_key && security_level_sufficient){
3850                 connection->link_key_type = link_key_type;
3851                 hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
3852             } else {
3853                 hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
3854             }
3855             return true;
3856         }
3857 
3858         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
3859             log_info("denying to pin request");
3860             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
3861             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
3862             return true;
3863         }
3864 
3865         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
3866             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
3867             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
3868             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
3869                 // tweak authentication requirements
3870                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
3871                 if (connection->bonding_flags & BONDING_DEDICATED){
3872                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
3873                 }
3874                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
3875                     authreq |= 1;
3876                 }
3877                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
3878             } else {
3879                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
3880             }
3881             return true;
3882         }
3883 
3884         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
3885             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
3886             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
3887             return true;
3888         }
3889 
3890         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
3891             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
3892             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
3893             return true;
3894         }
3895 
3896         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_0){
3897             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_0;
3898             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
3899             return true;
3900         }
3901 
3902         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_1){
3903             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_1;
3904             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 1);
3905             return true;
3906         }
3907 
3908         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES_PAGE_2){
3909             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES_PAGE_2;
3910             hci_send_cmd(&hci_read_remote_extended_features_command, connection->con_handle, 2);
3911             return true;
3912         }
3913 
3914         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
3915             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
3916             connection->bonding_flags |= BONDING_EMIT_COMPLETE_ON_DISCONNECT;
3917             connection->state = SENT_DISCONNECT;
3918             hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
3919             return true;
3920         }
3921 
3922         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
3923             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
3924             connection->bonding_flags |= BONDING_SENT_AUTHENTICATE_REQUEST;
3925             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
3926             return true;
3927         }
3928 
3929         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
3930             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
3931             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
3932             return true;
3933         }
3934         if (connection->bonding_flags & BONDING_SEND_READ_ENCRYPTION_KEY_SIZE){
3935             connection->bonding_flags &= ~BONDING_SEND_READ_ENCRYPTION_KEY_SIZE;
3936             hci_send_cmd(&hci_read_encryption_key_size, connection->con_handle, 1);
3937             return true;
3938         }
3939 #endif
3940 
3941         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
3942             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
3943             if (connection->state != SENT_DISCONNECT){
3944                 connection->state = SENT_DISCONNECT;
3945                 hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_AUTHENTICATION_FAILURE);
3946                 return true;
3947             }
3948         }
3949 
3950 #ifdef ENABLE_CLASSIC
3951         uint16_t sniff_min_interval;
3952         switch (connection->sniff_min_interval){
3953             case 0:
3954                 break;
3955             case 0xffff:
3956                 connection->sniff_min_interval = 0;
3957                 hci_send_cmd(&hci_exit_sniff_mode, connection->con_handle);
3958                 return true;
3959             default:
3960                 sniff_min_interval = connection->sniff_min_interval;
3961                 connection->sniff_min_interval = 0;
3962                 hci_send_cmd(&hci_sniff_mode, connection->con_handle, connection->sniff_max_interval, sniff_min_interval, connection->sniff_attempt, connection->sniff_timeout);
3963                 return true;
3964         }
3965 #endif
3966 
3967 #ifdef ENABLE_BLE
3968         switch (connection->le_con_parameter_update_state){
3969             // response to L2CAP CON PARAMETER UPDATE REQUEST
3970             case CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS:
3971                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3972                 hci_send_cmd(&hci_le_connection_update, connection->con_handle, connection->le_conn_interval_min,
3973                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3974                              0x0000, 0xffff);
3975                 return true;
3976             case CON_PARAMETER_UPDATE_REPLY:
3977                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3978                 hci_send_cmd(&hci_le_remote_connection_parameter_request_reply, connection->con_handle, connection->le_conn_interval_min,
3979                              connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout,
3980                              0x0000, 0xffff);
3981                 return true;
3982             case CON_PARAMETER_UPDATE_NEGATIVE_REPLY:
3983                 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE;
3984                 hci_send_cmd(&hci_le_remote_connection_parameter_request_negative_reply, ERROR_CODE_UNSUPPORTED_LMP_PARAMETER_VALUE_UNSUPPORTED_LL_PARAMETER_VALUE);
3985                 return true;
3986             default:
3987                 break;
3988         }
3989         if (connection->le_phy_update_all_phys != 0xff){
3990             uint8_t all_phys = connection->le_phy_update_all_phys;
3991             connection->le_phy_update_all_phys = 0xff;
3992             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);
3993             return true;
3994         }
3995 #endif
3996     }
3997     return false;
3998 }
3999 
4000 static void hci_run(void){
4001 
4002     bool done;
4003 
4004     // send continuation fragments first, as they block the prepared packet buffer
4005     done = hci_run_acl_fragments();
4006     if (done) return;
4007 
4008 #ifdef ENABLE_HCI_CONTROLLER_TO_HOST_FLOW_CONTROL
4009     // send host num completed packets next as they don't require num_cmd_packets > 0
4010     if (!hci_can_send_comand_packet_transport()) return;
4011     if (hci_stack->host_completed_packets){
4012         hci_host_num_completed_packets();
4013         return;
4014     }
4015 #endif
4016 
4017     if (!hci_can_send_command_packet_now()) return;
4018 
4019     // global/non-connection oriented commands
4020 
4021 
4022 #ifdef ENABLE_CLASSIC
4023     // general gap classic
4024     done = hci_run_general_gap_classic();
4025     if (done) return;
4026 #endif
4027 
4028 #ifdef ENABLE_BLE
4029     // general gap le
4030     done = hci_run_general_gap_le();
4031     if (done) return;
4032 #endif
4033 
4034     // send pending HCI commands
4035     done = hci_run_general_pending_commmands();
4036     if (done) return;
4037 
4038     // stack state sub statemachines
4039     hci_connection_t * connection;
4040     switch (hci_stack->state){
4041         case HCI_STATE_INITIALIZING:
4042             hci_initializing_run();
4043             break;
4044 
4045         case HCI_STATE_HALTING:
4046 
4047             log_info("HCI_STATE_HALTING, substate %x\n", hci_stack->substate);
4048             switch (hci_stack->substate){
4049                 case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
4050                 case HCI_HALTING_DISCONNECT_ALL_TIMER:
4051 
4052 #ifdef ENABLE_BLE
4053 #ifdef ENABLE_LE_CENTRAL
4054                     // free whitelist entries
4055                     {
4056                         btstack_linked_list_iterator_t lit;
4057                         btstack_linked_list_iterator_init(&lit, &hci_stack->le_whitelist);
4058                         while (btstack_linked_list_iterator_has_next(&lit)){
4059                             whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&lit);
4060                             btstack_linked_list_remove(&hci_stack->le_whitelist, (btstack_linked_item_t *) entry);
4061                             btstack_memory_whitelist_entry_free(entry);
4062                         }
4063                     }
4064 #endif
4065 #endif
4066                     // close all open connections
4067                     connection =  (hci_connection_t *) hci_stack->connections;
4068                     if (connection){
4069                         hci_con_handle_t con_handle = (uint16_t) connection->con_handle;
4070                         if (!hci_can_send_command_packet_now()) return;
4071 
4072                         // check state
4073                         if (connection->state == SENT_DISCONNECT) return;
4074                         connection->state = SENT_DISCONNECT;
4075 
4076                         log_info("HCI_STATE_HALTING, connection %p, handle %u", connection, con_handle);
4077 
4078                         // cancel all l2cap connections right away instead of waiting for disconnection complete event ...
4079                         hci_emit_disconnection_complete(con_handle, 0x16); // terminated by local host
4080 
4081                         // ... which would be ignored anyway as we shutdown (free) the connection now
4082                         hci_shutdown_connection(connection);
4083 
4084                         // finally, send the disconnect command
4085                         hci_send_cmd(&hci_disconnect, con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4086                         return;
4087                     }
4088 
4089                     if (hci_stack->substate == HCI_HALTING_DISCONNECT_ALL_TIMER){
4090                         // no connections left, wait a bit to assert that btstack_cyrpto isn't waiting for an HCI event
4091                         log_info("HCI_STATE_HALTING: wait 50 ms");
4092                         hci_stack->substate = HCI_HALTING_W4_TIMER;
4093                         btstack_run_loop_set_timer(&hci_stack->timeout, 50);
4094                         btstack_run_loop_set_timer_handler(&hci_stack->timeout, hci_halting_timeout_handler);
4095                         btstack_run_loop_add_timer(&hci_stack->timeout);
4096                         break;
4097                     }
4098 
4099                     /* fall through */
4100 
4101                 case HCI_HALTING_CLOSE:
4102                     log_info("HCI_STATE_HALTING, calling off");
4103 
4104                     // switch mode
4105                     hci_power_control_off();
4106 
4107                     log_info("HCI_STATE_HALTING, emitting state");
4108                     hci_emit_state();
4109                     log_info("HCI_STATE_HALTING, done");
4110                     break;
4111 
4112                 case HCI_HALTING_W4_TIMER:
4113                     // keep waiting
4114 
4115                     break;
4116                 default:
4117                     break;
4118             }
4119 
4120             break;
4121 
4122         case HCI_STATE_FALLING_ASLEEP:
4123             switch(hci_stack->substate) {
4124                 case HCI_FALLING_ASLEEP_DISCONNECT:
4125                     log_info("HCI_STATE_FALLING_ASLEEP");
4126                     // close all open connections
4127                     connection =  (hci_connection_t *) hci_stack->connections;
4128 
4129 #ifdef HAVE_PLATFORM_IPHONE_OS
4130                     // don't close connections, if H4 supports power management
4131                     if (btstack_control_iphone_power_management_enabled()){
4132                         connection = NULL;
4133                     }
4134 #endif
4135                     if (connection){
4136 
4137                         // send disconnect
4138                         if (!hci_can_send_command_packet_now()) return;
4139 
4140                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u", connection, (uint16_t)connection->con_handle);
4141                         hci_send_cmd(&hci_disconnect, connection->con_handle, ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION);
4142 
4143                         // send disconnected event right away - causes higher layer connections to get closed, too.
4144                         hci_shutdown_connection(connection);
4145                         return;
4146                     }
4147 
4148                     if (hci_classic_supported()){
4149                         // disable page and inquiry scan
4150                         if (!hci_can_send_command_packet_now()) return;
4151 
4152                         log_info("HCI_STATE_HALTING, disabling inq scans");
4153                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
4154 
4155                         // continue in next sub state
4156                         hci_stack->substate = HCI_FALLING_ASLEEP_W4_WRITE_SCAN_ENABLE;
4157                         break;
4158                     }
4159 
4160                     /* fall through */
4161 
4162                 case HCI_FALLING_ASLEEP_COMPLETE:
4163                     log_info("HCI_STATE_HALTING, calling sleep");
4164 #ifdef HAVE_PLATFORM_IPHONE_OS
4165                     // don't actually go to sleep, if H4 supports power management
4166                     if (btstack_control_iphone_power_management_enabled()){
4167                         // SLEEP MODE reached
4168                         hci_stack->state = HCI_STATE_SLEEPING;
4169                         hci_emit_state();
4170                         break;
4171                     }
4172 #endif
4173                     // switch mode
4174                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
4175                     hci_emit_state();
4176                     break;
4177 
4178                 default:
4179                     break;
4180             }
4181             break;
4182 
4183         default:
4184             break;
4185     }
4186 }
4187 
4188 int hci_send_cmd_packet(uint8_t *packet, int size){
4189     // house-keeping
4190 
4191 #ifdef ENABLE_CLASSIC
4192     bd_addr_t addr;
4193     hci_connection_t * conn;
4194 #endif
4195 #ifdef ENABLE_LE_CENTRAL
4196     uint8_t initiator_filter_policy;
4197 #endif
4198 
4199     uint16_t opcode = little_endian_read_16(packet, 0);
4200     switch (opcode) {
4201         case HCI_OPCODE_HCI_WRITE_LOOPBACK_MODE:
4202             hci_stack->loopback_mode = packet[3];
4203             break;
4204 
4205 #ifdef ENABLE_CLASSIC
4206         case HCI_OPCODE_HCI_CREATE_CONNECTION:
4207             reverse_bd_addr(&packet[3], addr);
4208             log_info("Create_connection to %s", bd_addr_to_str(addr));
4209 
4210             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4211             if (!conn) {
4212                 conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4213                 if (!conn) {
4214                     // notify client that alloc failed
4215                     hci_emit_connection_complete(addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4216                     return -1; // packet not sent to controller
4217                 }
4218                 conn->state = SEND_CREATE_CONNECTION;
4219             }
4220             log_info("conn state %u", conn->state);
4221             switch (conn->state) {
4222                 // if connection active exists
4223                 case OPEN:
4224                     // and OPEN, emit connection complete command
4225                     hci_emit_connection_complete(addr, conn->con_handle, 0);
4226                     return -1; // packet not sent to controller
4227                 case RECEIVED_DISCONNECTION_COMPLETE:
4228                     // create connection triggered in disconnect complete event, let's do it now
4229                     break;
4230                 case SEND_CREATE_CONNECTION:
4231                     // connection created by hci, e.g. dedicated bonding, but not executed yet, let's do it now
4232                     break;
4233                 default:
4234                     // otherwise, just ignore as it is already in the open process
4235                     return -1; // packet not sent to controller
4236             }
4237             conn->state = SENT_CREATE_CONNECTION;
4238 
4239             // track outgoing connection
4240             hci_stack->outgoing_addr_type = BD_ADDR_TYPE_ACL;
4241             (void) memcpy(hci_stack->outgoing_addr, addr, 6);
4242             break;
4243         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_REPLY:
4244             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
4245             break;
4246         case HCI_OPCODE_HCI_LINK_KEY_REQUEST_NEGATIVE_REPLY:
4247             hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
4248             break;
4249         case HCI_OPCODE_HCI_DELETE_STORED_LINK_KEY:
4250             if (hci_stack->link_key_db) {
4251                 reverse_bd_addr(&packet[3], addr);
4252                 hci_stack->link_key_db->delete_link_key(addr);
4253             }
4254             break;
4255         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_NEGATIVE_REPLY:
4256         case HCI_OPCODE_HCI_PIN_CODE_REQUEST_REPLY:
4257             reverse_bd_addr(&packet[3], addr);
4258             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4259             if (conn) {
4260                 connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
4261             }
4262             break;
4263         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_NEGATIVE_REPLY:
4264         case HCI_OPCODE_HCI_USER_CONFIRMATION_REQUEST_REPLY:
4265         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_NEGATIVE_REPLY:
4266         case HCI_OPCODE_HCI_USER_PASSKEY_REQUEST_REPLY:
4267             reverse_bd_addr(&packet[3], addr);
4268             conn = hci_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
4269             if (conn) {
4270                 connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
4271             }
4272             break;
4273 
4274 #ifdef ENABLE_SCO_OVER_HCI
4275         case HCI_OPCODE_HCI_SETUP_SYNCHRONOUS_CONNECTION:
4276             // setup_synchronous_connection? Voice setting at offset 22
4277             // TODO: compare to current setting if sco connection already active
4278             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 15);
4279             break;
4280         case HCI_OPCODE_HCI_ACCEPT_SYNCHRONOUS_CONNECTION:
4281             // accept_synchronus_connection? Voice setting at offset 18
4282             // TODO: compare to current setting if sco connection already active
4283             hci_stack->sco_voice_setting_active = little_endian_read_16(packet, 19);
4284             break;
4285 #endif
4286 #endif
4287 
4288 #ifdef ENABLE_BLE
4289         case HCI_OPCODE_HCI_LE_SET_RANDOM_ADDRESS:
4290             hci_stack->le_random_address_set = 1;
4291             reverse_bd_addr(&packet[3], hci_stack->le_random_address);
4292             break;
4293 #ifdef ENABLE_LE_PERIPHERAL
4294         case HCI_OPCODE_HCI_LE_SET_ADVERTISE_ENABLE:
4295             hci_stack->le_advertisements_active = packet[3];
4296             break;
4297 #endif
4298 #ifdef ENABLE_LE_CENTRAL
4299         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION:
4300             // white list used?
4301             initiator_filter_policy = packet[7];
4302             switch (initiator_filter_policy) {
4303                 case 0:
4304                     // whitelist not used
4305                     hci_stack->le_connecting_state = LE_CONNECTING_DIRECT;
4306                     break;
4307                 case 1:
4308                     hci_stack->le_connecting_state = LE_CONNECTING_WHITELIST;
4309                     break;
4310                 default:
4311                     log_error("Invalid initiator_filter_policy in LE Create Connection %u", initiator_filter_policy);
4312                     break;
4313             }
4314             break;
4315         case HCI_OPCODE_HCI_LE_CREATE_CONNECTION_CANCEL:
4316             hci_stack->le_connecting_state = LE_CONNECTING_IDLE;
4317             break;
4318 #endif
4319 #endif
4320         default:
4321             break;
4322     }
4323 
4324     hci_stack->num_cmd_packets--;
4325 
4326     hci_dump_packet(HCI_COMMAND_DATA_PACKET, 0, packet, size);
4327     return hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
4328 }
4329 
4330 // disconnect because of security block
4331 void hci_disconnect_security_block(hci_con_handle_t con_handle){
4332     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4333     if (!connection) return;
4334     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
4335 }
4336 
4337 
4338 // Configure Secure Simple Pairing
4339 
4340 #ifdef ENABLE_CLASSIC
4341 
4342 // enable will enable SSP during init
4343 void gap_ssp_set_enable(int enable){
4344     hci_stack->ssp_enable = enable;
4345 }
4346 
4347 static int hci_local_ssp_activated(void){
4348     return gap_ssp_supported() && hci_stack->ssp_enable;
4349 }
4350 
4351 // if set, BTstack will respond to io capability request using authentication requirement
4352 void gap_ssp_set_io_capability(int io_capability){
4353     hci_stack->ssp_io_capability = io_capability;
4354 }
4355 void gap_ssp_set_authentication_requirement(int authentication_requirement){
4356     hci_stack->ssp_authentication_requirement = authentication_requirement;
4357 }
4358 
4359 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
4360 void gap_ssp_set_auto_accept(int auto_accept){
4361     hci_stack->ssp_auto_accept = auto_accept;
4362 }
4363 
4364 void gap_secure_connections_enable(bool enable){
4365     hci_stack->secure_connections_enable = enable;
4366 }
4367 
4368 #endif
4369 
4370 // va_list part of hci_send_cmd
4371 int hci_send_cmd_va_arg(const hci_cmd_t *cmd, va_list argptr){
4372     if (!hci_can_send_command_packet_now()){
4373         log_error("hci_send_cmd called but cannot send packet now");
4374         return 0;
4375     }
4376 
4377     // for HCI INITIALIZATION
4378     // log_info("hci_send_cmd: opcode %04x", cmd->opcode);
4379     hci_stack->last_cmd_opcode = cmd->opcode;
4380 
4381     hci_reserve_packet_buffer();
4382     uint8_t * packet = hci_stack->hci_packet_buffer;
4383     uint16_t size = hci_cmd_create_from_template(packet, cmd, argptr);
4384     int err = hci_send_cmd_packet(packet, size);
4385 
4386     // release packet buffer on error or for synchronous transport implementations
4387     if ((err < 0) || hci_transport_synchronous()){
4388         hci_release_packet_buffer();
4389         hci_emit_transport_packet_sent();
4390     }
4391 
4392     return err;
4393 }
4394 
4395 /**
4396  * pre: numcmds >= 0 - it's allowed to send a command to the controller
4397  */
4398 int hci_send_cmd(const hci_cmd_t *cmd, ...){
4399     va_list argptr;
4400     va_start(argptr, cmd);
4401     int res = hci_send_cmd_va_arg(cmd, argptr);
4402     va_end(argptr);
4403     return res;
4404 }
4405 
4406 // Create various non-HCI events.
4407 // TODO: generalize, use table similar to hci_create_command
4408 
4409 static void hci_emit_event(uint8_t * event, uint16_t size, int dump){
4410     // dump packet
4411     if (dump) {
4412         hci_dump_packet( HCI_EVENT_PACKET, 0, event, size);
4413     }
4414 
4415     // dispatch to all event handlers
4416     btstack_linked_list_iterator_t it;
4417     btstack_linked_list_iterator_init(&it, &hci_stack->event_handlers);
4418     while (btstack_linked_list_iterator_has_next(&it)){
4419         btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it);
4420         entry->callback(HCI_EVENT_PACKET, 0, event, size);
4421     }
4422 }
4423 
4424 static void hci_emit_acl_packet(uint8_t * packet, uint16_t size){
4425     if (!hci_stack->acl_packet_handler) return;
4426     hci_stack->acl_packet_handler(HCI_ACL_DATA_PACKET, 0, packet, size);
4427 }
4428 
4429 #ifdef ENABLE_CLASSIC
4430 static void hci_notify_if_sco_can_send_now(void){
4431     // notify SCO sender if waiting
4432     if (!hci_stack->sco_waiting_for_can_send_now) return;
4433     if (hci_can_send_sco_packet_now()){
4434         hci_stack->sco_waiting_for_can_send_now = 0;
4435         uint8_t event[2] = { HCI_EVENT_SCO_CAN_SEND_NOW, 0 };
4436         hci_dump_packet(HCI_EVENT_PACKET, 1, event, sizeof(event));
4437         hci_stack->sco_packet_handler(HCI_EVENT_PACKET, 0, event, sizeof(event));
4438     }
4439 }
4440 
4441 // parsing end emitting has been merged to reduce code size
4442 static void gap_inquiry_explode(uint8_t *packet, uint16_t size) {
4443     uint8_t event[19+GAP_INQUIRY_MAX_NAME_LEN];
4444 
4445     uint8_t * eir_data;
4446     ad_context_t context;
4447     const uint8_t * name;
4448     uint8_t         name_len;
4449 
4450     if (size < 3) return;
4451 
4452     int event_type = hci_event_packet_get_type(packet);
4453     int num_reserved_fields = (event_type == HCI_EVENT_INQUIRY_RESULT) ? 2 : 1;    // 2 for old event, 1 otherwise
4454     int num_responses       = hci_event_inquiry_result_get_num_responses(packet);
4455 
4456     switch (event_type){
4457         case HCI_EVENT_INQUIRY_RESULT:
4458         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4459             if (size != (3 + (num_responses * 14))) return;
4460             break;
4461         case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4462             if (size != 257) return;
4463             if (num_responses != 1) return;
4464             break;
4465         default:
4466             return;
4467     }
4468 
4469     // event[1] is set at the end
4470     int i;
4471     for (i=0; i<num_responses;i++){
4472         memset(event, 0, sizeof(event));
4473         event[0] = GAP_EVENT_INQUIRY_RESULT;
4474         uint8_t event_size = 18;    // if name is not set by EIR
4475 
4476         (void)memcpy(&event[2], &packet[3 + (i * 6)], 6); // bd_addr
4477         event[8] =          packet[3 + (num_responses*(6))                         + (i*1)];     // page_scan_repetition_mode
4478         (void)memcpy(&event[9],
4479                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields)) + (i * 3)],
4480                      3); // class of device
4481         (void)memcpy(&event[12],
4482                      &packet[3 + (num_responses * (6 + 1 + num_reserved_fields + 3)) + (i * 2)],
4483                      2); // clock offset
4484 
4485         switch (event_type){
4486             case HCI_EVENT_INQUIRY_RESULT:
4487                 // 14,15,16,17 = 0, size 18
4488                 break;
4489             case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
4490                 event[14] = 1;
4491                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4492                 // 16,17 = 0, size 18
4493                 break;
4494             case HCI_EVENT_EXTENDED_INQUIRY_RESPONSE:
4495                 event[14] = 1;
4496                 event[15] = packet [3 + (num_responses*(6+1+num_reserved_fields+3+2)) + (i*1)]; // rssi
4497                 // EIR packets only contain a single inquiry response
4498                 eir_data = &packet[3 + (6+1+num_reserved_fields+3+2+1)];
4499                 name = NULL;
4500                 // Iterate over EIR data
4501                 for (ad_iterator_init(&context, EXTENDED_INQUIRY_RESPONSE_DATA_LEN, eir_data) ; ad_iterator_has_more(&context) ; ad_iterator_next(&context)){
4502                     uint8_t data_type    = ad_iterator_get_data_type(&context);
4503                     uint8_t data_size    = ad_iterator_get_data_len(&context);
4504                     const uint8_t * data = ad_iterator_get_data(&context);
4505                     // Prefer Complete Local Name over Shortend Local Name
4506                     switch (data_type){
4507                         case BLUETOOTH_DATA_TYPE_SHORTENED_LOCAL_NAME:
4508                             if (name) continue;
4509                             /* fall through */
4510                         case BLUETOOTH_DATA_TYPE_COMPLETE_LOCAL_NAME:
4511                             name = data;
4512                             name_len = data_size;
4513                             break;
4514                         default:
4515                             break;
4516                     }
4517                 }
4518                 if (name){
4519                     event[16] = 1;
4520                     // truncate name if needed
4521                     int len = btstack_min(name_len, GAP_INQUIRY_MAX_NAME_LEN);
4522                     event[17] = len;
4523                     (void)memcpy(&event[18], name, len);
4524                     event_size += len;
4525                 }
4526                 break;
4527         }
4528         event[1] = event_size - 2;
4529         hci_emit_event(event, event_size, 1);
4530     }
4531 }
4532 #endif
4533 
4534 void hci_emit_state(void){
4535     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
4536     uint8_t event[3];
4537     event[0] = BTSTACK_EVENT_STATE;
4538     event[1] = sizeof(event) - 2;
4539     event[2] = hci_stack->state;
4540     hci_emit_event(event, sizeof(event), 1);
4541 }
4542 
4543 #ifdef ENABLE_CLASSIC
4544 static void hci_emit_connection_complete(bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4545     uint8_t event[13];
4546     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
4547     event[1] = sizeof(event) - 2;
4548     event[2] = status;
4549     little_endian_store_16(event, 3, con_handle);
4550     reverse_bd_addr(address, &event[5]);
4551     event[11] = 1; // ACL connection
4552     event[12] = 0; // encryption disabled
4553     hci_emit_event(event, sizeof(event), 1);
4554 }
4555 static void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
4556     if (disable_l2cap_timeouts) return;
4557     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
4558     uint8_t event[4];
4559     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
4560     event[1] = sizeof(event) - 2;
4561     little_endian_store_16(event, 2, conn->con_handle);
4562     hci_emit_event(event, sizeof(event), 1);
4563 }
4564 #endif
4565 
4566 #ifdef ENABLE_BLE
4567 #ifdef ENABLE_LE_CENTRAL
4568 static void hci_emit_le_connection_complete(uint8_t address_type, bd_addr_t address, hci_con_handle_t con_handle, uint8_t status){
4569     uint8_t event[21];
4570     event[0] = HCI_EVENT_LE_META;
4571     event[1] = sizeof(event) - 2;
4572     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
4573     event[3] = status;
4574     little_endian_store_16(event, 4, con_handle);
4575     event[6] = 0; // TODO: role
4576     event[7] = address_type;
4577     reverse_bd_addr(address, &event[8]);
4578     little_endian_store_16(event, 14, 0); // interval
4579     little_endian_store_16(event, 16, 0); // latency
4580     little_endian_store_16(event, 18, 0); // supervision timeout
4581     event[20] = 0; // master clock accuracy
4582     hci_emit_event(event, sizeof(event), 1);
4583 }
4584 #endif
4585 #endif
4586 
4587 static void hci_emit_transport_packet_sent(void){
4588     // notify upper stack that it might be possible to send again
4589     uint8_t event[] = { HCI_EVENT_TRANSPORT_PACKET_SENT, 0};
4590     hci_emit_event(&event[0], sizeof(event), 0);  // don't dump
4591 }
4592 
4593 static void hci_emit_disconnection_complete(hci_con_handle_t con_handle, uint8_t reason){
4594     uint8_t event[6];
4595     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
4596     event[1] = sizeof(event) - 2;
4597     event[2] = 0; // status = OK
4598     little_endian_store_16(event, 3, con_handle);
4599     event[5] = reason;
4600     hci_emit_event(event, sizeof(event), 1);
4601 }
4602 
4603 static void hci_emit_nr_connections_changed(void){
4604     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
4605     uint8_t event[3];
4606     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
4607     event[1] = sizeof(event) - 2;
4608     event[2] = nr_hci_connections();
4609     hci_emit_event(event, sizeof(event), 1);
4610 }
4611 
4612 static void hci_emit_hci_open_failed(void){
4613     log_info("BTSTACK_EVENT_POWERON_FAILED");
4614     uint8_t event[2];
4615     event[0] = BTSTACK_EVENT_POWERON_FAILED;
4616     event[1] = sizeof(event) - 2;
4617     hci_emit_event(event, sizeof(event), 1);
4618 }
4619 
4620 static void hci_emit_dedicated_bonding_result(bd_addr_t address, uint8_t status){
4621     log_info("hci_emit_dedicated_bonding_result %u ", status);
4622     uint8_t event[9];
4623     int pos = 0;
4624     event[pos++] = GAP_EVENT_DEDICATED_BONDING_COMPLETED;
4625     event[pos++] = sizeof(event) - 2;
4626     event[pos++] = status;
4627     reverse_bd_addr(address, &event[pos]);
4628     hci_emit_event(event, sizeof(event), 1);
4629 }
4630 
4631 
4632 #ifdef ENABLE_CLASSIC
4633 
4634 static void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
4635     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
4636     uint8_t event[5];
4637     int pos = 0;
4638     event[pos++] = GAP_EVENT_SECURITY_LEVEL;
4639     event[pos++] = sizeof(event) - 2;
4640     little_endian_store_16(event, 2, con_handle);
4641     pos += 2;
4642     event[pos++] = level;
4643     hci_emit_event(event, sizeof(event), 1);
4644 }
4645 
4646 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
4647     if (!connection) return LEVEL_0;
4648     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
4649     if ((connection->authentication_flags & CONNECTION_AUTHENTICATED) == 0) return LEVEL_0;
4650     if (connection->encryption_key_size < hci_stack->gap_required_encyrption_key_size) return LEVEL_0;
4651     gap_security_level_t security_level = gap_security_level_for_link_key_type(connection->link_key_type);
4652     // LEVEL 4 always requires 128 bit encrytion key size
4653     if ((security_level == LEVEL_4) && (connection->encryption_key_size < 16)){
4654         security_level = LEVEL_3;
4655     }
4656     return security_level;
4657 }
4658 
4659 static void hci_emit_discoverable_enabled(uint8_t enabled){
4660     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
4661     uint8_t event[3];
4662     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
4663     event[1] = sizeof(event) - 2;
4664     event[2] = enabled;
4665     hci_emit_event(event, sizeof(event), 1);
4666 }
4667 
4668 // query if remote side supports eSCO
4669 int hci_remote_esco_supported(hci_con_handle_t con_handle){
4670     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4671     if (!connection) return 0;
4672     return (connection->remote_supported_features[0] & 1) != 0;
4673 }
4674 
4675 static bool hci_ssp_supported(hci_connection_t * connection){
4676     const uint8_t mask = BONDING_REMOTE_SUPPORTS_SSP_CONTROLLER | BONDING_REMOTE_SUPPORTS_SSP_HOST;
4677     return (connection->bonding_flags & mask) == mask;
4678 }
4679 
4680 // query if remote side supports SSP
4681 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
4682     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4683     if (!connection) return 0;
4684     return hci_ssp_supported(connection) ? 1 : 0;
4685 }
4686 
4687 int gap_ssp_supported_on_both_sides(hci_con_handle_t handle){
4688     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
4689 }
4690 
4691 // GAP API
4692 /**
4693  * @bbrief enable/disable bonding. default is enabled
4694  * @praram enabled
4695  */
4696 void gap_set_bondable_mode(int enable){
4697     hci_stack->bondable = enable ? 1 : 0;
4698 }
4699 /**
4700  * @brief Get bondable mode.
4701  * @return 1 if bondable
4702  */
4703 int gap_get_bondable_mode(void){
4704     return hci_stack->bondable;
4705 }
4706 
4707 /**
4708  * @brief map link keys to security levels
4709  */
4710 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
4711     switch (link_key_type){
4712         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4713             return LEVEL_4;
4714         case COMBINATION_KEY:
4715         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4716             return LEVEL_3;
4717         default:
4718             return LEVEL_2;
4719     }
4720 }
4721 
4722 /**
4723  * @brief map link keys to secure connection yes/no
4724  */
4725 int gap_secure_connection_for_link_key_type(link_key_type_t link_key_type){
4726     switch (link_key_type){
4727         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4728         case UNAUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4729             return 1;
4730         default:
4731             return 0;
4732     }
4733 }
4734 
4735 /**
4736  * @brief map link keys to authenticated
4737  */
4738 int gap_authenticated_for_link_key_type(link_key_type_t link_key_type){
4739     switch (link_key_type){
4740         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
4741         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
4742             return 1;
4743         default:
4744             return 0;
4745     }
4746 }
4747 
4748 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
4749     log_info("gap_mitm_protection_required_for_security_level %u", level);
4750     return level > LEVEL_2;
4751 }
4752 
4753 /**
4754  * @brief get current security level
4755  */
4756 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
4757     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4758     if (!connection) return LEVEL_0;
4759     return gap_security_level_for_connection(connection);
4760 }
4761 
4762 /**
4763  * @brief request connection to device to
4764  * @result GAP_AUTHENTICATION_RESULT
4765  */
4766 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
4767     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4768     if (!connection){
4769         hci_emit_security_level(con_handle, LEVEL_0);
4770         return;
4771     }
4772     gap_security_level_t current_level = gap_security_level(con_handle);
4773     log_info("gap_request_security_level requested level %u, planned level %u, current level %u",
4774         requested_level, connection->requested_security_level, current_level);
4775 
4776     // assumption: earlier requested security higher than current level => security request is active
4777     if (current_level < connection->requested_security_level){
4778         if (connection->requested_security_level < requested_level){
4779             // increase requested level as new level is higher
4780 
4781             // TODO: handle re-authentication when done
4782 
4783             connection->requested_security_level = requested_level;
4784         }
4785         return;
4786     }
4787 
4788     // no request active, notify if security sufficient
4789     if (requested_level <= current_level){
4790         hci_emit_security_level(con_handle, current_level);
4791         return;
4792     }
4793 
4794     // start pairing to increase security level
4795     connection->requested_security_level = requested_level;
4796 
4797 #if 0
4798     // sending encryption request without a link key results in an error.
4799     // TODO: figure out how to use it properly
4800 
4801     // would enabling ecnryption suffice (>= LEVEL_2)?
4802     if (hci_stack->link_key_db){
4803         link_key_type_t link_key_type;
4804         link_key_t      link_key;
4805         if (hci_stack->link_key_db->get_link_key( &connection->address, &link_key, &link_key_type)){
4806             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
4807                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
4808                 return;
4809             }
4810         }
4811     }
4812 #endif
4813 
4814     // start to authenticate connection if not already active
4815     if ((connection->bonding_flags & BONDING_SENT_AUTHENTICATE_REQUEST) != 0) return;
4816     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
4817     hci_run();
4818 }
4819 
4820 /**
4821  * @brief start dedicated bonding with device. disconnect after bonding
4822  * @param device
4823  * @param request MITM protection
4824  * @result GAP_DEDICATED_BONDING_COMPLETE
4825  */
4826 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
4827 
4828     // create connection state machine
4829     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_ACL);
4830 
4831     if (!connection){
4832         return BTSTACK_MEMORY_ALLOC_FAILED;
4833     }
4834 
4835     // delete linkn key
4836     gap_drop_link_key_for_bd_addr(device);
4837 
4838     // configure LEVEL_2/3, dedicated bonding
4839     connection->state = SEND_CREATE_CONNECTION;
4840     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
4841     log_info("gap_dedicated_bonding, mitm %d -> level %u", mitm_protection_required, connection->requested_security_level);
4842     connection->bonding_flags = BONDING_DEDICATED;
4843 
4844     // wait for GAP Security Result and send GAP Dedicated Bonding complete
4845 
4846     // handle: connnection failure (connection complete != ok)
4847     // handle: authentication failure
4848     // handle: disconnect on done
4849 
4850     hci_run();
4851 
4852     return 0;
4853 }
4854 #endif
4855 
4856 void gap_set_local_name(const char * local_name){
4857     hci_stack->local_name = local_name;
4858 }
4859 
4860 
4861 #ifdef ENABLE_BLE
4862 
4863 #ifdef ENABLE_LE_CENTRAL
4864 void gap_start_scan(void){
4865     hci_stack->le_scanning_enabled = 1;
4866     hci_run();
4867 }
4868 
4869 void gap_stop_scan(void){
4870     hci_stack->le_scanning_enabled = 0;
4871     hci_run();
4872 }
4873 
4874 void gap_set_scan_parameters(uint8_t scan_type, uint16_t scan_interval, uint16_t scan_window){
4875     hci_stack->le_scan_type     = scan_type;
4876     hci_stack->le_scan_interval = scan_interval;
4877     hci_stack->le_scan_window   = scan_window;
4878     hci_run();
4879 }
4880 
4881 uint8_t gap_connect(bd_addr_t addr, bd_addr_type_t addr_type){
4882     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
4883     if (!conn){
4884         log_info("gap_connect: no connection exists yet, creating context");
4885         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
4886         if (!conn){
4887             // notify client that alloc failed
4888             hci_emit_le_connection_complete(addr_type, addr, 0, BTSTACK_MEMORY_ALLOC_FAILED);
4889             log_info("gap_connect: failed to alloc hci_connection_t");
4890             return GATT_CLIENT_NOT_CONNECTED; // don't sent packet to controller
4891         }
4892         conn->state = SEND_CREATE_CONNECTION;
4893         log_info("gap_connect: send create connection next");
4894         hci_run();
4895         return ERROR_CODE_SUCCESS;
4896     }
4897 
4898     if (!hci_is_le_connection(conn) ||
4899         (conn->state == SEND_CREATE_CONNECTION) ||
4900         (conn->state == SENT_CREATE_CONNECTION)) {
4901         hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_COMMAND_DISALLOWED);
4902         log_error("gap_connect: classic connection or connect is already being created");
4903         return GATT_CLIENT_IN_WRONG_STATE;
4904     }
4905 
4906     // check if connection was just disconnected
4907     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
4908         log_info("gap_connect: send create connection (again)");
4909         conn->state = SEND_CREATE_CONNECTION;
4910         hci_run();
4911         return ERROR_CODE_SUCCESS;
4912     }
4913 
4914     log_info("gap_connect: context exists with state %u", conn->state);
4915     hci_emit_le_connection_complete(conn->address_type, conn->address, conn->con_handle, 0);
4916     hci_run();
4917     return ERROR_CODE_SUCCESS;
4918 }
4919 
4920 // @assumption: only a single outgoing LE Connection exists
4921 static hci_connection_t * gap_get_outgoing_connection(void){
4922     btstack_linked_item_t *it;
4923     for (it = (btstack_linked_item_t *) hci_stack->connections; it != NULL; it = it->next){
4924         hci_connection_t * conn = (hci_connection_t *) it;
4925         if (!hci_is_le_connection(conn)) continue;
4926         switch (conn->state){
4927             case SEND_CREATE_CONNECTION:
4928             case SENT_CREATE_CONNECTION:
4929             case SENT_CANCEL_CONNECTION:
4930                 return conn;
4931             default:
4932                 break;
4933         };
4934     }
4935     return NULL;
4936 }
4937 
4938 uint8_t gap_connect_cancel(void){
4939     hci_connection_t * conn = gap_get_outgoing_connection();
4940     if (!conn) return 0;
4941     switch (conn->state){
4942         case SEND_CREATE_CONNECTION:
4943             // skip sending create connection and emit event instead
4944             hci_emit_le_connection_complete(conn->address_type, conn->address, 0, ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER);
4945             btstack_linked_list_remove(&hci_stack->connections, (btstack_linked_item_t *) conn);
4946             btstack_memory_hci_connection_free( conn );
4947             break;
4948         case SENT_CREATE_CONNECTION:
4949             // request to send cancel connection
4950             conn->state = SEND_CANCEL_CONNECTION;
4951             hci_run();
4952             break;
4953         default:
4954             break;
4955     }
4956     return 0;
4957 }
4958 #endif
4959 
4960 #ifdef ENABLE_LE_CENTRAL
4961 /**
4962  * @brief Set connection parameters for outgoing connections
4963  * @param conn_scan_interval (unit: 0.625 msec), default: 60 ms
4964  * @param conn_scan_window (unit: 0.625 msec), default: 30 ms
4965  * @param conn_interval_min (unit: 1.25ms), default: 10 ms
4966  * @param conn_interval_max (unit: 1.25ms), default: 30 ms
4967  * @param conn_latency, default: 4
4968  * @param supervision_timeout (unit: 10ms), default: 720 ms
4969  * @param min_ce_length (unit: 0.625ms), default: 10 ms
4970  * @param max_ce_length (unit: 0.625ms), default: 30 ms
4971  */
4972 
4973 void gap_set_connection_parameters(uint16_t conn_scan_interval, uint16_t conn_scan_window,
4974     uint16_t conn_interval_min, uint16_t conn_interval_max, uint16_t conn_latency,
4975     uint16_t supervision_timeout, uint16_t min_ce_length, uint16_t max_ce_length){
4976     hci_stack->le_connection_scan_interval = conn_scan_interval;
4977     hci_stack->le_connection_scan_window = conn_scan_window;
4978     hci_stack->le_connection_interval_min = conn_interval_min;
4979     hci_stack->le_connection_interval_max = conn_interval_max;
4980     hci_stack->le_connection_latency = conn_latency;
4981     hci_stack->le_supervision_timeout = supervision_timeout;
4982     hci_stack->le_minimum_ce_length = min_ce_length;
4983     hci_stack->le_maximum_ce_length = max_ce_length;
4984 }
4985 #endif
4986 
4987 /**
4988  * @brief Updates the connection parameters for a given LE connection
4989  * @param handle
4990  * @param conn_interval_min (unit: 1.25ms)
4991  * @param conn_interval_max (unit: 1.25ms)
4992  * @param conn_latency
4993  * @param supervision_timeout (unit: 10ms)
4994  * @returns 0 if ok
4995  */
4996 int gap_update_connection_parameters(hci_con_handle_t con_handle, uint16_t conn_interval_min,
4997     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
4998     hci_connection_t * connection = hci_connection_for_handle(con_handle);
4999     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5000     connection->le_conn_interval_min = conn_interval_min;
5001     connection->le_conn_interval_max = conn_interval_max;
5002     connection->le_conn_latency = conn_latency;
5003     connection->le_supervision_timeout = supervision_timeout;
5004     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS;
5005     hci_run();
5006     return 0;
5007 }
5008 
5009 /**
5010  * @brief Request an update of the connection parameter for a given LE connection
5011  * @param handle
5012  * @param conn_interval_min (unit: 1.25ms)
5013  * @param conn_interval_max (unit: 1.25ms)
5014  * @param conn_latency
5015  * @param supervision_timeout (unit: 10ms)
5016  * @returns 0 if ok
5017  */
5018 int gap_request_connection_parameter_update(hci_con_handle_t con_handle, uint16_t conn_interval_min,
5019     uint16_t conn_interval_max, uint16_t conn_latency, uint16_t supervision_timeout){
5020     hci_connection_t * connection = hci_connection_for_handle(con_handle);
5021     if (!connection) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5022     connection->le_conn_interval_min = conn_interval_min;
5023     connection->le_conn_interval_max = conn_interval_max;
5024     connection->le_conn_latency = conn_latency;
5025     connection->le_supervision_timeout = supervision_timeout;
5026     connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_REQUEST;
5027     uint8_t l2cap_trigger_run_event[2] = { L2CAP_EVENT_TRIGGER_RUN, 0};
5028     hci_emit_event(l2cap_trigger_run_event, sizeof(l2cap_trigger_run_event), 0);
5029     return 0;
5030 }
5031 
5032 #ifdef ENABLE_LE_PERIPHERAL
5033 
5034 static void gap_advertisments_changed(void){
5035     // disable advertisements before updating adv, scan data, or adv params
5036     if (hci_stack->le_advertisements_active){
5037         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE | LE_ADVERTISEMENT_TASKS_ENABLE;
5038     }
5039     hci_run();
5040 }
5041 
5042 /**
5043  * @brief Set Advertisement Data
5044  * @param advertising_data_length
5045  * @param advertising_data (max 31 octets)
5046  * @note data is not copied, pointer has to stay valid
5047  */
5048 void gap_advertisements_set_data(uint8_t advertising_data_length, uint8_t * advertising_data){
5049     hci_stack->le_advertisements_data_len = advertising_data_length;
5050     hci_stack->le_advertisements_data = advertising_data;
5051     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_ADV_DATA;
5052     gap_advertisments_changed();
5053 }
5054 
5055 /**
5056  * @brief Set Scan Response Data
5057  * @param advertising_data_length
5058  * @param advertising_data (max 31 octets)
5059  * @note data is not copied, pointer has to stay valid
5060  */
5061 void gap_scan_response_set_data(uint8_t scan_response_data_length, uint8_t * scan_response_data){
5062     hci_stack->le_scan_response_data_len = scan_response_data_length;
5063     hci_stack->le_scan_response_data = scan_response_data;
5064     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_SCAN_DATA;
5065     gap_advertisments_changed();
5066 }
5067 
5068 /**
5069  * @brief Set Advertisement Parameters
5070  * @param adv_int_min
5071  * @param adv_int_max
5072  * @param adv_type
5073  * @param direct_address_type
5074  * @param direct_address
5075  * @param channel_map
5076  * @param filter_policy
5077  *
5078  * @note internal use. use gap_advertisements_set_params from gap_le.h instead.
5079  */
5080  void hci_le_advertisements_set_params(uint16_t adv_int_min, uint16_t adv_int_max, uint8_t adv_type,
5081     uint8_t direct_address_typ, bd_addr_t direct_address,
5082     uint8_t channel_map, uint8_t filter_policy) {
5083 
5084     hci_stack->le_advertisements_interval_min = adv_int_min;
5085     hci_stack->le_advertisements_interval_max = adv_int_max;
5086     hci_stack->le_advertisements_type = adv_type;
5087     hci_stack->le_advertisements_direct_address_type = direct_address_typ;
5088     hci_stack->le_advertisements_channel_map = channel_map;
5089     hci_stack->le_advertisements_filter_policy = filter_policy;
5090     (void)memcpy(hci_stack->le_advertisements_direct_address, direct_address,
5091                  6);
5092 
5093     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5094     gap_advertisments_changed();
5095  }
5096 
5097 /**
5098  * @brief Enable/Disable Advertisements
5099  * @param enabled
5100  */
5101 void gap_advertisements_enable(int enabled){
5102     hci_stack->le_advertisements_enabled = enabled;
5103     if (enabled && !hci_stack->le_advertisements_active){
5104         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_ENABLE;
5105     }
5106     if (!enabled && hci_stack->le_advertisements_active){
5107         hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_DISABLE;
5108     }
5109     hci_run();
5110 }
5111 
5112 #endif
5113 
5114 void hci_le_set_own_address_type(uint8_t own_address_type){
5115     log_info("hci_le_set_own_address_type: old %u, new %u", hci_stack->le_own_addr_type, own_address_type);
5116     if (own_address_type == hci_stack->le_own_addr_type) return;
5117     hci_stack->le_own_addr_type = own_address_type;
5118 
5119 #ifdef ENABLE_LE_PERIPHERAL
5120     // update advertisement parameters, too
5121     hci_stack->le_advertisements_todo |= LE_ADVERTISEMENT_TASKS_SET_PARAMS;
5122     gap_advertisments_changed();
5123 #endif
5124 #ifdef ENABLE_LE_CENTRAL
5125     // note: we don't update scan parameters or modify ongoing connection attempts
5126 #endif
5127 }
5128 
5129 #endif
5130 
5131 uint8_t gap_disconnect(hci_con_handle_t handle){
5132     hci_connection_t * conn = hci_connection_for_handle(handle);
5133     if (!conn){
5134         hci_emit_disconnection_complete(handle, 0);
5135         return 0;
5136     }
5137     // ignore if already disconnected
5138     if (conn->state == RECEIVED_DISCONNECTION_COMPLETE){
5139         return 0;
5140     }
5141     conn->state = SEND_DISCONNECT;
5142     hci_run();
5143     return 0;
5144 }
5145 
5146 int gap_read_rssi(hci_con_handle_t con_handle){
5147     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5148     if (hci_connection == NULL) return 0;
5149     connectionSetAuthenticationFlags(hci_connection, READ_RSSI);
5150     hci_run();
5151     return 1;
5152 }
5153 
5154 /**
5155  * @brief Get connection type
5156  * @param con_handle
5157  * @result connection_type
5158  */
5159 gap_connection_type_t gap_get_connection_type(hci_con_handle_t connection_handle){
5160     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5161     if (!conn) return GAP_CONNECTION_INVALID;
5162     switch (conn->address_type){
5163         case BD_ADDR_TYPE_LE_PUBLIC:
5164         case BD_ADDR_TYPE_LE_RANDOM:
5165             return GAP_CONNECTION_LE;
5166         case BD_ADDR_TYPE_SCO:
5167             return GAP_CONNECTION_SCO;
5168         case BD_ADDR_TYPE_ACL:
5169             return GAP_CONNECTION_ACL;
5170         default:
5171             return GAP_CONNECTION_INVALID;
5172     }
5173 }
5174 
5175 #ifdef ENABLE_BLE
5176 
5177 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){
5178     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5179     if (!conn) return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER;
5180 
5181     conn->le_phy_update_all_phys    = all_phys;
5182     conn->le_phy_update_tx_phys     = tx_phys;
5183     conn->le_phy_update_rx_phys     = rx_phys;
5184     conn->le_phy_update_phy_options = phy_options;
5185 
5186     hci_run();
5187 
5188     return 0;
5189 }
5190 
5191 #ifdef ENABLE_LE_CENTRAL
5192 /**
5193  * @brief Auto Connection Establishment - Start Connecting to device
5194  * @param address_typ
5195  * @param address
5196  * @returns 0 if ok
5197  */
5198 int gap_auto_connection_start(bd_addr_type_t address_type, bd_addr_t address){
5199     // check capacity
5200     int num_entries = btstack_linked_list_count(&hci_stack->le_whitelist);
5201     if (num_entries >= hci_stack->le_whitelist_capacity) return ERROR_CODE_MEMORY_CAPACITY_EXCEEDED;
5202     whitelist_entry_t * entry = btstack_memory_whitelist_entry_get();
5203     if (!entry) return BTSTACK_MEMORY_ALLOC_FAILED;
5204     entry->address_type = address_type;
5205     (void)memcpy(entry->address, address, 6);
5206     entry->state = LE_WHITELIST_ADD_TO_CONTROLLER;
5207     btstack_linked_list_add(&hci_stack->le_whitelist, (btstack_linked_item_t*) entry);
5208     hci_run();
5209     return 0;
5210 }
5211 
5212 static void hci_remove_from_whitelist(bd_addr_type_t address_type, bd_addr_t address){
5213     btstack_linked_list_iterator_t it;
5214     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5215     while (btstack_linked_list_iterator_has_next(&it)){
5216         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5217         if (entry->address_type != address_type) continue;
5218         if (memcmp(entry->address, address, 6) != 0) continue;
5219         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5220             // remove from controller if already present
5221             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5222             continue;
5223         }
5224         // direclty remove entry from whitelist
5225         btstack_linked_list_iterator_remove(&it);
5226         btstack_memory_whitelist_entry_free(entry);
5227     }
5228 }
5229 
5230 /**
5231  * @brief Auto Connection Establishment - Stop Connecting to device
5232  * @param address_typ
5233  * @param address
5234  * @returns 0 if ok
5235  */
5236 int gap_auto_connection_stop(bd_addr_type_t address_type, bd_addr_t address){
5237     hci_remove_from_whitelist(address_type, address);
5238     hci_run();
5239     return 0;
5240 }
5241 
5242 /**
5243  * @brief Auto Connection Establishment - Stop everything
5244  * @note  Convenience function to stop all active auto connection attempts
5245  */
5246 void gap_auto_connection_stop_all(void){
5247     btstack_linked_list_iterator_t it;
5248     btstack_linked_list_iterator_init(&it, &hci_stack->le_whitelist);
5249     while (btstack_linked_list_iterator_has_next(&it)){
5250         whitelist_entry_t * entry = (whitelist_entry_t*) btstack_linked_list_iterator_next(&it);
5251         if (entry->state & LE_WHITELIST_ON_CONTROLLER){
5252             // remove from controller if already present
5253             entry->state |= LE_WHITELIST_REMOVE_FROM_CONTROLLER;
5254             continue;
5255         }
5256         // directly remove entry from whitelist
5257         btstack_linked_list_iterator_remove(&it);
5258         btstack_memory_whitelist_entry_free(entry);
5259     }
5260     hci_run();
5261 }
5262 
5263 uint16_t gap_le_connection_interval(hci_con_handle_t connection_handle){
5264     hci_connection_t * conn = hci_connection_for_handle(connection_handle);
5265     if (!conn) return 0;
5266     return conn->le_connection_interval;
5267 }
5268 #endif
5269 #endif
5270 
5271 #ifdef ENABLE_CLASSIC
5272 /**
5273  * @brief Set Extended Inquiry Response data
5274  * @param eir_data size HCI_EXTENDED_INQUIRY_RESPONSE_DATA_LEN (240) bytes, is not copied make sure memory is accessible during stack startup
5275  * @note has to be done before stack starts up
5276  */
5277 void gap_set_extended_inquiry_response(const uint8_t * data){
5278     hci_stack->eir_data = data;
5279 }
5280 
5281 /**
5282  * @brief Start GAP Classic Inquiry
5283  * @param duration in 1.28s units
5284  * @return 0 if ok
5285  * @events: GAP_EVENT_INQUIRY_RESULT, GAP_EVENT_INQUIRY_COMPLETE
5286  */
5287 int gap_inquiry_start(uint8_t duration_in_1280ms_units){
5288     if (hci_stack->state != HCI_STATE_WORKING) return ERROR_CODE_COMMAND_DISALLOWED;
5289     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5290     if ((duration_in_1280ms_units < GAP_INQUIRY_DURATION_MIN) || (duration_in_1280ms_units > GAP_INQUIRY_DURATION_MAX)){
5291         return ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS;
5292     }
5293     hci_stack->inquiry_state = duration_in_1280ms_units;
5294     hci_run();
5295     return 0;
5296 }
5297 
5298 /**
5299  * @brief Stop GAP Classic Inquiry
5300  * @returns 0 if ok
5301  */
5302 int gap_inquiry_stop(void){
5303     if ((hci_stack->inquiry_state >= GAP_INQUIRY_DURATION_MIN) && (hci_stack->inquiry_state <= GAP_INQUIRY_DURATION_MAX)) {
5304         // emit inquiry complete event, before it even started
5305         uint8_t event[] = { GAP_EVENT_INQUIRY_COMPLETE, 1, 0};
5306         hci_emit_event(event, sizeof(event), 1);
5307         return 0;
5308     }
5309     if (hci_stack->inquiry_state != GAP_INQUIRY_STATE_ACTIVE) return ERROR_CODE_COMMAND_DISALLOWED;
5310     hci_stack->inquiry_state = GAP_INQUIRY_STATE_W2_CANCEL;
5311     hci_run();
5312     return 0;
5313 }
5314 
5315 
5316 /**
5317  * @brief Remote Name Request
5318  * @param addr
5319  * @param page_scan_repetition_mode
5320  * @param clock_offset only used when bit 15 is set
5321  * @events: HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
5322  */
5323 int gap_remote_name_request(bd_addr_t addr, uint8_t page_scan_repetition_mode, uint16_t clock_offset){
5324     if (hci_stack->remote_name_state != GAP_REMOTE_NAME_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5325     (void)memcpy(hci_stack->remote_name_addr, addr, 6);
5326     hci_stack->remote_name_page_scan_repetition_mode = page_scan_repetition_mode;
5327     hci_stack->remote_name_clock_offset = clock_offset;
5328     hci_stack->remote_name_state = GAP_REMOTE_NAME_STATE_W2_SEND;
5329     hci_run();
5330     return 0;
5331 }
5332 
5333 static int gap_pairing_set_state_and_run(bd_addr_t addr, uint8_t state){
5334     hci_stack->gap_pairing_state = state;
5335     (void)memcpy(hci_stack->gap_pairing_addr, addr, 6);
5336     hci_run();
5337     return 0;
5338 }
5339 
5340 /**
5341  * @brief Legacy Pairing Pin Code Response
5342  * @param addr
5343  * @param pin
5344  * @return 0 if ok
5345  */
5346 int gap_pin_code_response(bd_addr_t addr, const char * pin){
5347     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5348     hci_stack->gap_pairing_input.gap_pairing_pin = pin;
5349     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN);
5350 }
5351 
5352 /**
5353  * @brief Abort Legacy Pairing
5354  * @param addr
5355  * @param pin
5356  * @return 0 if ok
5357  */
5358 int gap_pin_code_negative(bd_addr_t addr){
5359     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5360     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PIN_NEGATIVE);
5361 }
5362 
5363 /**
5364  * @brief SSP Passkey Response
5365  * @param addr
5366  * @param passkey
5367  * @return 0 if ok
5368  */
5369 int gap_ssp_passkey_response(bd_addr_t addr, uint32_t passkey){
5370     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5371     hci_stack->gap_pairing_input.gap_pairing_passkey = passkey;
5372     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY);
5373 }
5374 
5375 /**
5376  * @brief Abort SSP Passkey Entry/Pairing
5377  * @param addr
5378  * @param pin
5379  * @return 0 if ok
5380  */
5381 int gap_ssp_passkey_negative(bd_addr_t addr){
5382     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5383     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_PASSKEY_NEGATIVE);
5384 }
5385 
5386 /**
5387  * @brief Accept SSP Numeric Comparison
5388  * @param addr
5389  * @param passkey
5390  * @return 0 if ok
5391  */
5392 int gap_ssp_confirmation_response(bd_addr_t addr){
5393     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5394     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION);
5395 }
5396 
5397 /**
5398  * @brief Abort SSP Numeric Comparison/Pairing
5399  * @param addr
5400  * @param pin
5401  * @return 0 if ok
5402  */
5403 int gap_ssp_confirmation_negative(bd_addr_t addr){
5404     if (hci_stack->gap_pairing_state != GAP_PAIRING_STATE_IDLE) return ERROR_CODE_COMMAND_DISALLOWED;
5405     return gap_pairing_set_state_and_run(addr, GAP_PAIRING_STATE_SEND_CONFIRMATION_NEGATIVE);
5406 }
5407 
5408 /**
5409  * @brief Set inquiry mode: standard, with RSSI, with RSSI + Extended Inquiry Results. Has to be called before power on.
5410  * @param inquiry_mode see bluetooth_defines.h
5411  */
5412 void hci_set_inquiry_mode(inquiry_mode_t mode){
5413     hci_stack->inquiry_mode = mode;
5414 }
5415 
5416 /**
5417  * @brief Configure Voice Setting for use with SCO data in HSP/HFP
5418  */
5419 void hci_set_sco_voice_setting(uint16_t voice_setting){
5420     hci_stack->sco_voice_setting = voice_setting;
5421 }
5422 
5423 /**
5424  * @brief Get SCO Voice Setting
5425  * @return current voice setting
5426  */
5427 uint16_t hci_get_sco_voice_setting(void){
5428     return hci_stack->sco_voice_setting;
5429 }
5430 
5431 static int hci_have_usb_transport(void){
5432     if (!hci_stack->hci_transport) return 0;
5433     const char * transport_name = hci_stack->hci_transport->name;
5434     if (!transport_name) return 0;
5435     return (transport_name[0] == 'H') && (transport_name[1] == '2');
5436 }
5437 
5438 /** @brief Get SCO packet length for current SCO Voice setting
5439  *  @note  Using SCO packets of the exact length is required for USB transfer
5440  *  @return Length of SCO packets in bytes (not audio frames)
5441  */
5442 int hci_get_sco_packet_length(void){
5443     int sco_packet_length = 0;
5444 
5445 #ifdef ENABLE_SCO_OVER_HCI
5446 
5447     // Transparent = mSBC => 1, CVSD with 16-bit samples requires twice as much bytes
5448     int multiplier = ((hci_stack->sco_voice_setting_active & 0x03) == 0x03) ? 1 : 2;
5449 
5450     if (hci_have_usb_transport()){
5451         // see Core Spec for H2 USB Transfer.
5452         // 3 byte SCO header + 24 bytes per connection
5453         int num_sco_connections = btstack_max(1, hci_number_sco_connections());
5454         sco_packet_length = 3 + 24 * num_sco_connections * multiplier;
5455     } else {
5456         // 3 byte SCO header + SCO packet size over the air (60 bytes)
5457         sco_packet_length = 3 + 60 * multiplier;
5458         // assert that it still fits inside an SCO buffer
5459         if (sco_packet_length > hci_stack->sco_data_packet_length){
5460             sco_packet_length = 3 + 60;
5461         }
5462     }
5463 #endif
5464     return sco_packet_length;
5465 }
5466 
5467 /**
5468 * @brief Sets the master/slave policy
5469 * @param policy (0: attempt to become master, 1: let connecting device decide)
5470 */
5471 void hci_set_master_slave_policy(uint8_t policy){
5472     hci_stack->master_slave_policy = policy;
5473 }
5474 
5475 #endif
5476 
5477 HCI_STATE hci_get_state(void){
5478     return hci_stack->state;
5479 }
5480 
5481 #ifdef ENABLE_CLASSIC
5482 void gap_register_classic_connection_filter(int (*accept_callback)(bd_addr_t addr)){
5483     hci_stack->gap_classic_accept_callback = accept_callback;
5484 }
5485 #endif
5486 
5487 /**
5488  * @brief Set callback for Bluetooth Hardware Error
5489  */
5490 void hci_set_hardware_error_callback(void (*fn)(uint8_t error)){
5491     hci_stack->hardware_error_callback = fn;
5492 }
5493 
5494 void hci_disconnect_all(void){
5495     btstack_linked_list_iterator_t it;
5496     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5497     while (btstack_linked_list_iterator_has_next(&it)){
5498         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5499         if (con->state == SENT_DISCONNECT) continue;
5500         con->state = SEND_DISCONNECT;
5501     }
5502     hci_run();
5503 }
5504 
5505 uint16_t hci_get_manufacturer(void){
5506     return hci_stack->manufacturer;
5507 }
5508 
5509 #ifdef ENABLE_BLE
5510 
5511 static sm_connection_t * sm_get_connection_for_handle(hci_con_handle_t con_handle){
5512     hci_connection_t * hci_con = hci_connection_for_handle(con_handle);
5513     if (!hci_con) return NULL;
5514     return &hci_con->sm_connection;
5515 }
5516 
5517 // extracted from sm.c to allow enabling of l2cap le data channels without adding sm.c to the build
5518 // without sm.c default values from create_connection_for_bd_addr_and_type() resulg in non-encrypted, not-authenticated
5519 
5520 int gap_encryption_key_size(hci_con_handle_t con_handle){
5521     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5522     if (hci_connection == NULL) return 0;
5523     if (hci_is_le_connection(hci_connection)){
5524         sm_connection_t * sm_conn = &hci_connection->sm_connection;
5525         if (sm_conn->sm_connection_encrypted) {
5526             return sm_conn->sm_actual_encryption_key_size;
5527         }
5528     }
5529 #ifdef ENABLE_CLASSIC
5530     else {
5531         if ((hci_connection->authentication_flags & CONNECTION_ENCRYPTED)){
5532             return hci_connection->encryption_key_size;
5533         }
5534     }
5535 #endif
5536     return 0;
5537 }
5538 
5539 int gap_authenticated(hci_con_handle_t con_handle){
5540     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5541     if (hci_connection == NULL) return 0;
5542 
5543     switch (hci_connection->address_type){
5544         case BD_ADDR_TYPE_LE_PUBLIC:
5545         case BD_ADDR_TYPE_LE_RANDOM:
5546             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5547             return hci_connection->sm_connection.sm_connection_authenticated;
5548 #ifdef ENABLE_CLASSIC
5549         case BD_ADDR_TYPE_SCO:
5550         case BD_ADDR_TYPE_ACL:
5551             return gap_authenticated_for_link_key_type(hci_connection->link_key_type);
5552 #endif
5553         default:
5554             return 0;
5555     }
5556 }
5557 
5558 int gap_secure_connection(hci_con_handle_t con_handle){
5559     hci_connection_t * hci_connection = hci_connection_for_handle(con_handle);
5560     if (hci_connection == NULL) return 0;
5561 
5562     switch (hci_connection->address_type){
5563         case BD_ADDR_TYPE_LE_PUBLIC:
5564         case BD_ADDR_TYPE_LE_RANDOM:
5565             if (hci_connection->sm_connection.sm_connection_encrypted == 0) return 0; // unencrypted connection cannot be authenticated
5566             return hci_connection->sm_connection.sm_connection_sc;
5567 #ifdef ENABLE_CLASSIC
5568         case BD_ADDR_TYPE_SCO:
5569         case BD_ADDR_TYPE_ACL:
5570             return gap_secure_connection_for_link_key_type(hci_connection->link_key_type);
5571 #endif
5572         default:
5573             return 0;
5574     }
5575 }
5576 
5577 authorization_state_t gap_authorization_state(hci_con_handle_t con_handle){
5578     sm_connection_t * sm_conn = sm_get_connection_for_handle(con_handle);
5579     if (!sm_conn) return AUTHORIZATION_UNKNOWN;     // wrong connection
5580     if (!sm_conn->sm_connection_encrypted)               return AUTHORIZATION_UNKNOWN; // unencrypted connection cannot be authorized
5581     if (!sm_conn->sm_connection_authenticated)           return AUTHORIZATION_UNKNOWN; // unauthenticatd connection cannot be authorized
5582     return sm_conn->sm_connection_authorization_state;
5583 }
5584 #endif
5585 
5586 #ifdef ENABLE_CLASSIC
5587 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){
5588     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5589     if (!conn) return GAP_CONNECTION_INVALID;
5590     conn->sniff_min_interval = sniff_min_interval;
5591     conn->sniff_max_interval = sniff_max_interval;
5592     conn->sniff_attempt = sniff_attempt;
5593     conn->sniff_timeout = sniff_timeout;
5594     hci_run();
5595     return 0;
5596 }
5597 
5598 /**
5599  * @brief Exit Sniff mode
5600  * @param con_handle
5601  @ @return 0 if ok
5602  */
5603 uint8_t gap_sniff_mode_exit(hci_con_handle_t con_handle){
5604     hci_connection_t * conn = hci_connection_for_handle(con_handle);
5605     if (!conn) return GAP_CONNECTION_INVALID;
5606     conn->sniff_min_interval = 0xffff;
5607     hci_run();
5608     return 0;
5609 }
5610 #endif
5611 
5612 void hci_halting_defer(void){
5613     if (hci_stack->state != HCI_STATE_HALTING) return;
5614     switch (hci_stack->substate){
5615         case HCI_HALTING_DISCONNECT_ALL_NO_TIMER:
5616         case HCI_HALTING_CLOSE:
5617             hci_stack->substate = HCI_HALTING_DISCONNECT_ALL_TIMER;
5618             break;
5619         default:
5620             break;
5621     }
5622 }
5623 
5624 #ifdef FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION
5625 void hci_setup_test_connections_fuzz(void){
5626     hci_connection_t * conn;
5627 
5628     // default address: 66:55:44:33:00:01
5629     bd_addr_t addr = { 0x66, 0x55, 0x44, 0x33, 0x00, 0x00};
5630 
5631     // setup Controller info
5632     hci_stack->num_cmd_packets = 255;
5633     hci_stack->acl_packets_total_num = 255;
5634 
5635     // setup incoming Classic ACL connection with con handle 0x0001, 66:55:44:33:22:01
5636     addr[5] = 0x01;
5637     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5638     conn->con_handle = addr[5];
5639     conn->role  = HCI_ROLE_SLAVE;
5640     conn->state = RECEIVED_CONNECTION_REQUEST;
5641     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5642 
5643     // setup incoming Classic SCO connection with con handle 0x0002
5644     addr[5] = 0x02;
5645     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5646     conn->con_handle = addr[5];
5647     conn->role  = HCI_ROLE_SLAVE;
5648     conn->state = RECEIVED_CONNECTION_REQUEST;
5649     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5650 
5651     // setup ready Classic ACL connection with con handle 0x0003
5652     addr[5] = 0x03;
5653     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_ACL);
5654     conn->con_handle = addr[5];
5655     conn->role  = HCI_ROLE_SLAVE;
5656     conn->state = OPEN;
5657     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5658 
5659     // setup ready Classic SCO connection with con handle 0x0004
5660     addr[5] = 0x04;
5661     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_SCO);
5662     conn->con_handle = addr[5];
5663     conn->role  = HCI_ROLE_SLAVE;
5664     conn->state = OPEN;
5665     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5666 
5667     // setup ready LE ACL connection with con handle 0x005 and public address
5668     addr[5] = 0x05;
5669     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_LE_PUBLIC);
5670     conn->con_handle = addr[5];
5671     conn->role  = HCI_ROLE_SLAVE;
5672     conn->state = OPEN;
5673     conn->sm_connection.sm_role = HCI_ROLE_SLAVE;
5674 }
5675 
5676 void hci_free_connections_fuzz(void){
5677     btstack_linked_list_iterator_t it;
5678     btstack_linked_list_iterator_init(&it, &hci_stack->connections);
5679     while (btstack_linked_list_iterator_has_next(&it)){
5680         hci_connection_t * con = (hci_connection_t*) btstack_linked_list_iterator_next(&it);
5681         btstack_linked_list_iterator_remove(&it);
5682         btstack_memory_hci_connection_free(con);
5683     }
5684 }
5685 void hci_simulate_working_fuzz(void){
5686     hci_init_done();
5687     hci_stack->num_cmd_packets = 255;
5688 }
5689 #endif
5690