xref: /btstack/src/hci.c (revision 2b552b2306fa072c814a621715edcba6eda58f3e)
1 /*
2  * Copyright (C) 2009-2012 by Matthias Ringwald
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 MATTHIAS RINGWALD 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 [email protected]
34  *
35  */
36 
37 /*
38  *  hci.c
39  *
40  *  Created by Matthias Ringwald on 4/29/09.
41  *
42  */
43 
44 #include "btstack-config.h"
45 
46 #include "hci.h"
47 #include "gap.h"
48 
49 #include <stdarg.h>
50 #include <string.h>
51 #include <stdio.h>
52 
53 #ifndef EMBEDDED
54 #include <unistd.h> // gethostbyname
55 #include <btstack/version.h>
56 #endif
57 
58 #include "btstack_memory.h"
59 #include "debug.h"
60 #include "hci_dump.h"
61 
62 #include <btstack/hci_cmds.h>
63 
64 #define HCI_CONNECTION_TIMEOUT_MS 10000
65 
66 #define HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP 11
67 
68 #ifdef USE_BLUETOOL
69 #include "bt_control_iphone.h"
70 #endif
71 
72 static void hci_update_scan_enable(void);
73 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection);
74 static void hci_connection_timeout_handler(timer_source_t *timer);
75 static void hci_connection_timestamp(hci_connection_t *connection);
76 
77 // the STACK is here
78 #ifndef HAVE_MALLOC
79 static hci_stack_t   hci_stack_static;
80 #endif
81 static hci_stack_t * hci_stack = NULL;
82 
83 // test helper
84 static uint8_t disable_l2cap_timeouts = 0;
85 
86 /**
87  * create connection for given address
88  *
89  * @return connection OR NULL, if no memory left
90  */
91 static hci_connection_t * create_connection_for_bd_addr_and_type(bd_addr_t addr, bd_addr_type_t addr_type){
92 
93     printf("create_connection_for_addr %s\n", bd_addr_to_str(addr));
94     hci_connection_t * conn = (hci_connection_t *) btstack_memory_hci_connection_get();
95     if (!conn) return NULL;
96     BD_ADDR_COPY(conn->address, addr);
97     conn->address_type = addr_type;
98     conn->con_handle = 0xffff;
99     conn->authentication_flags = AUTH_FLAGS_NONE;
100     conn->bonding_flags = 0;
101     conn->requested_security_level = LEVEL_0;
102     linked_item_set_user(&conn->timeout.item, conn);
103     conn->timeout.process = hci_connection_timeout_handler;
104     hci_connection_timestamp(conn);
105     conn->acl_recombination_length = 0;
106     conn->acl_recombination_pos = 0;
107     conn->num_acl_packets_sent = 0;
108     linked_list_add(&hci_stack->connections, (linked_item_t *) conn);
109     return conn;
110 }
111 
112 /**
113  * get connection for a given handle
114  *
115  * @return connection OR NULL, if not found
116  */
117 hci_connection_t * hci_connection_for_handle(hci_con_handle_t con_handle){
118     linked_item_t *it;
119     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
120         if ( ((hci_connection_t *) it)->con_handle == con_handle){
121             return (hci_connection_t *) it;
122         }
123     }
124     return NULL;
125 }
126 
127 /**
128  * get connection for given address
129  *
130  * @return connection OR NULL, if not found
131  */
132 hci_connection_t * hci_connection_for_bd_addr_and_type(bd_addr_t * addr, bd_addr_type_t addr_type){
133     linked_item_t *it;
134     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
135         hci_connection_t * connection = (hci_connection_t *) it;
136         if (connection->address_type != addr_type)  continue;
137         if (memcmp(addr, connection->address, 6) != 0) continue;
138         return connection;
139     }
140     return NULL;
141 }
142 
143 static void hci_connection_timeout_handler(timer_source_t *timer){
144     hci_connection_t * connection = (hci_connection_t *) linked_item_get_user(&timer->item);
145 #ifdef HAVE_TIME
146     struct timeval tv;
147     gettimeofday(&tv, NULL);
148     if (tv.tv_sec >= connection->timestamp.tv_sec + HCI_CONNECTION_TIMEOUT_MS/1000) {
149         // connections might be timed out
150         hci_emit_l2cap_check_timeout(connection);
151     }
152 #endif
153 #ifdef HAVE_TICK
154     if (embedded_get_ticks() > connection->timestamp + embedded_ticks_for_ms(HCI_CONNECTION_TIMEOUT_MS)){
155         // connections might be timed out
156         hci_emit_l2cap_check_timeout(connection);
157     }
158 #endif
159     run_loop_set_timer(timer, HCI_CONNECTION_TIMEOUT_MS);
160     run_loop_add_timer(timer);
161 }
162 
163 static void hci_connection_timestamp(hci_connection_t *connection){
164 #ifdef HAVE_TIME
165     gettimeofday(&connection->timestamp, NULL);
166 #endif
167 #ifdef HAVE_TICK
168     connection->timestamp = embedded_get_ticks();
169 #endif
170 }
171 
172 
173 inline static void connectionSetAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
174     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags | flags);
175 }
176 
177 inline static void connectionClearAuthenticationFlags(hci_connection_t * conn, hci_authentication_flags_t flags){
178     conn->authentication_flags = (hci_authentication_flags_t)(conn->authentication_flags & ~flags);
179 }
180 
181 
182 /**
183  * add authentication flags and reset timer
184  * @note: assumes classic connection
185  */
186 static void hci_add_connection_flags_for_flipped_bd_addr(uint8_t *bd_addr, hci_authentication_flags_t flags){
187     bd_addr_t addr;
188     bt_flip_addr(addr, *(bd_addr_t *) bd_addr);
189     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
190     if (conn) {
191         connectionSetAuthenticationFlags(conn, flags);
192         hci_connection_timestamp(conn);
193     }
194 }
195 
196 int  hci_authentication_active_for_handle(hci_con_handle_t handle){
197     hci_connection_t * conn = hci_connection_for_handle(handle);
198     if (!conn) return 0;
199     if (conn->authentication_flags & LEGACY_PAIRING_ACTIVE) return 1;
200     if (conn->authentication_flags & SSP_PAIRING_ACTIVE) return 1;
201     return 0;
202 }
203 
204 void hci_drop_link_key_for_bd_addr(bd_addr_t *addr){
205     if (hci_stack->remote_device_db) {
206         hci_stack->remote_device_db->delete_link_key(addr);
207     }
208 }
209 
210 
211 /**
212  * count connections
213  */
214 static int nr_hci_connections(void){
215     int count = 0;
216     linked_item_t *it;
217     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next, count++);
218     return count;
219 }
220 
221 /**
222  * Dummy handler called by HCI
223  */
224 static void dummy_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
225 }
226 
227 uint8_t hci_number_outgoing_packets(hci_con_handle_t handle){
228     hci_connection_t * connection = hci_connection_for_handle(handle);
229     if (!connection) {
230         log_error("hci_number_outgoing_packets connectino for handle %u does not exist!\n", handle);
231         return 0;
232     }
233     return connection->num_acl_packets_sent;
234 }
235 
236 uint8_t hci_number_free_acl_slots(){
237     uint8_t free_slots = hci_stack->total_num_acl_packets;
238     linked_item_t *it;
239     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
240         hci_connection_t * connection = (hci_connection_t *) it;
241         if (free_slots < connection->num_acl_packets_sent) {
242             log_error("hci_number_free_acl_slots: sum of outgoing packets > total acl packets!\n");
243             return 0;
244         }
245         free_slots -= connection->num_acl_packets_sent;
246     }
247     return free_slots;
248 }
249 
250 int hci_can_send_packet_now(uint8_t packet_type){
251 
252     // check for async hci transport implementations
253     if (hci_stack->hci_transport->can_send_packet_now){
254         if (!hci_stack->hci_transport->can_send_packet_now(packet_type)){
255             return 0;
256         }
257     }
258 
259     // check regular Bluetooth flow control
260     switch (packet_type) {
261         case HCI_ACL_DATA_PACKET:
262             return hci_number_free_acl_slots();
263         case HCI_COMMAND_DATA_PACKET:
264             return hci_stack->num_cmd_packets;
265         default:
266             return 0;
267     }
268 }
269 
270 // same as hci_can_send_packet_now, but also checks if packet buffer is free for use
271 int hci_can_send_packet_now_using_packet_buffer(uint8_t packet_type){
272     if (hci_stack->hci_packet_buffer_reserved) return 0;
273     return hci_can_send_packet_now(packet_type);
274 }
275 
276 // used for internal checks in l2cap[-le].c
277 int hci_is_packet_buffer_reserved(void){
278     return hci_stack->hci_packet_buffer_reserved;
279 }
280 
281 // reserves outgoing packet buffer. @returns 1 if successful
282 int hci_reserve_packet_buffer(void){
283     if (hci_stack->hci_packet_buffer_reserved) return 0;
284     hci_stack->hci_packet_buffer_reserved = 1;
285     return 1;
286 }
287 
288 void hci_release_packet_buffer(void){
289     hci_stack->hci_packet_buffer_reserved = 0;
290 }
291 
292 // assumption: synchronous implementations don't provide can_send_packet_now as they don't keep the buffer after the call
293 int hci_transport_synchronous(void){
294     return hci_stack->hci_transport->can_send_packet_now == NULL;
295 }
296 
297 int hci_send_acl_packet(uint8_t *packet, int size){
298 
299     // check for free places on BT module
300     if (!hci_number_free_acl_slots()) return BTSTACK_ACL_BUFFERS_FULL;
301 
302     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
303     hci_connection_t *connection = hci_connection_for_handle( con_handle);
304     if (!connection) return 0;
305     hci_connection_timestamp(connection);
306 
307     // count packet
308     connection->num_acl_packets_sent++;
309     // log_info("hci_send_acl_packet - handle %u, sent %u\n", connection->con_handle, connection->num_acl_packets_sent);
310 
311     // send packet
312     int err = hci_stack->hci_transport->send_packet(HCI_ACL_DATA_PACKET, packet, size);
313 
314     // free packet buffer for synchronous transport implementations
315     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
316         hci_stack->hci_packet_buffer_reserved = 0;
317     }
318 
319     return err;
320 }
321 
322 static void acl_handler(uint8_t *packet, int size){
323 
324     // log_info("acl_handler: size %u", size);
325 
326     // get info
327     hci_con_handle_t con_handle = READ_ACL_CONNECTION_HANDLE(packet);
328     hci_connection_t *conn      = hci_connection_for_handle(con_handle);
329     uint8_t  acl_flags          = READ_ACL_FLAGS(packet);
330     uint16_t acl_length         = READ_ACL_LENGTH(packet);
331 
332     // ignore non-registered handle
333     if (!conn){
334         log_error( "hci.c: acl_handler called with non-registered handle %u!\n" , con_handle);
335         return;
336     }
337 
338     // assert packet is complete
339     if (acl_length + 4 != size){
340         log_error("hci.c: acl_handler called with ACL packet of wrong size %u, expected %u => dropping packet", size, acl_length + 4);
341         return;
342     }
343 
344     // update idle timestamp
345     hci_connection_timestamp(conn);
346 
347     // handle different packet types
348     switch (acl_flags & 0x03) {
349 
350         case 0x01: // continuation fragment
351 
352             // sanity check
353             if (conn->acl_recombination_pos == 0) {
354                 log_error( "ACL Cont Fragment but no first fragment for handle 0x%02x\n", con_handle);
355                 return;
356             }
357 
358             // append fragment payload (header already stored)
359             memcpy(&conn->acl_recombination_buffer[conn->acl_recombination_pos], &packet[4], acl_length );
360             conn->acl_recombination_pos += acl_length;
361 
362             // log_error( "ACL Cont Fragment: acl_len %u, combined_len %u, l2cap_len %u\n", acl_length,
363             //        conn->acl_recombination_pos, conn->acl_recombination_length);
364 
365             // forward complete L2CAP packet if complete.
366             if (conn->acl_recombination_pos >= conn->acl_recombination_length + 4 + 4){ // pos already incl. ACL header
367 
368                 hci_stack->packet_handler(HCI_ACL_DATA_PACKET, conn->acl_recombination_buffer, conn->acl_recombination_pos);
369                 // reset recombination buffer
370                 conn->acl_recombination_length = 0;
371                 conn->acl_recombination_pos = 0;
372             }
373             break;
374 
375         case 0x02: { // first fragment
376 
377             // sanity check
378             if (conn->acl_recombination_pos) {
379                 log_error( "ACL First Fragment but data in buffer for handle 0x%02x\n", con_handle);
380                 return;
381             }
382 
383             // peek into L2CAP packet!
384             uint16_t l2cap_length = READ_L2CAP_LENGTH( packet );
385 
386             // log_info( "ACL First Fragment: acl_len %u, l2cap_len %u\n", acl_length, l2cap_length);
387 
388             // compare fragment size to L2CAP packet size
389             if (acl_length >= l2cap_length + 4){
390 
391                 // forward fragment as L2CAP packet
392                 hci_stack->packet_handler(HCI_ACL_DATA_PACKET, packet, acl_length + 4);
393 
394             } else {
395                 // store first fragment and tweak acl length for complete package
396                 memcpy(conn->acl_recombination_buffer, packet, acl_length + 4);
397                 conn->acl_recombination_pos    = acl_length + 4;
398                 conn->acl_recombination_length = l2cap_length;
399                 bt_store_16(conn->acl_recombination_buffer, 2, l2cap_length +4);
400             }
401             break;
402 
403         }
404         default:
405             log_error( "hci.c: acl_handler called with invalid packet boundary flags %u\n", acl_flags & 0x03);
406             return;
407     }
408 
409     // execute main loop
410     hci_run();
411 }
412 
413 static void hci_shutdown_connection(hci_connection_t *conn){
414     log_info("Connection closed: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
415 
416     // cancel all l2cap connections
417     hci_emit_disconnection_complete(conn->con_handle, 0x16);    // terminated by local host
418 
419     run_loop_remove_timer(&conn->timeout);
420 
421     linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
422     btstack_memory_hci_connection_free( conn );
423 
424     // now it's gone
425     hci_emit_nr_connections_changed();
426 }
427 
428 static const uint16_t packet_type_sizes[] = {
429     0, HCI_ACL_2DH1_SIZE, HCI_ACL_3DH1_SIZE, HCI_ACL_DM1_SIZE,
430     HCI_ACL_DH1_SIZE, 0, 0, 0,
431     HCI_ACL_2DH3_SIZE, HCI_ACL_3DH3_SIZE, HCI_ACL_DM3_SIZE, HCI_ACL_DH3_SIZE,
432     HCI_ACL_2DH5_SIZE, HCI_ACL_3DH5_SIZE, HCI_ACL_DM5_SIZE, HCI_ACL_DH5_SIZE
433 };
434 static const uint8_t  packet_type_feature_requirement_bit[] = {
435      0, // 3 slot packets
436      1, // 5 slot packets
437     25, // EDR 2 mpbs
438     26, // EDR 3 mbps
439     39, // 3 slot EDR packts
440     40, // 5 slot EDR packet
441 };
442 static const uint16_t packet_type_feature_packet_mask[] = {
443     0x0f00, // 3 slot packets
444     0xf000, // 5 slot packets
445     0x1102, // EDR 2 mpbs
446     0x2204, // EDR 3 mbps
447     0x0300, // 3 slot EDR packts
448     0x3000, // 5 slot EDR packet
449 };
450 
451 static uint16_t hci_acl_packet_types_for_buffer_size_and_local_features(uint16_t buffer_size, uint8_t * local_supported_features){
452     // enable packet types based on size
453     uint16_t packet_types = 0;
454     int i;
455     for (i=0;i<16;i++){
456         if (packet_type_sizes[i] == 0) continue;
457         if (packet_type_sizes[i] <= buffer_size){
458             packet_types |= 1 << i;
459         }
460     }
461     // disable packet types due to missing local supported features
462     for (i=0;i<sizeof(packet_type_feature_requirement_bit);i++){
463         int bit_idx = packet_type_feature_requirement_bit[i];
464         int feature_set = (local_supported_features[bit_idx >> 3] & (1<<(bit_idx & 7))) != 0;
465         if (feature_set) continue;
466         log_info("Features bit %02u is not set, removing packet types 0x%04x", bit_idx, packet_type_feature_packet_mask[i]);
467         packet_types &= ~packet_type_feature_packet_mask[i];
468     }
469     // flip bits for "may not be used"
470     packet_types ^= 0x3306;
471     return packet_types;
472 }
473 
474 uint16_t hci_usable_acl_packet_types(void){
475     return hci_stack->packet_types;
476 }
477 
478 uint8_t* hci_get_outgoing_packet_buffer(void){
479     // hci packet buffer is >= acl data packet length
480     return hci_stack->hci_packet_buffer;
481 }
482 
483 uint16_t hci_max_acl_data_packet_length(void){
484     return hci_stack->acl_data_packet_length;
485 }
486 
487 int hci_ssp_supported(void){
488     // No 51, byte 6, bit 3
489     return (hci_stack->local_supported_features[6] & (1 << 3)) != 0;
490 }
491 
492 int hci_classic_supported(void){
493     // No 37, byte 4, bit 5, = No BR/EDR Support
494     return (hci_stack->local_supported_features[4] & (1 << 5)) == 0;
495 }
496 
497 int hci_le_supported(void){
498     // No 37, byte 4, bit 6 = LE Supported (Controller)
499 #ifdef HAVE_BLE
500     return (hci_stack->local_supported_features[4] & (1 << 6)) != 0;
501 #else
502     return 0;
503 #endif
504 }
505 
506 // get addr type and address used in advertisement packets
507 void hci_le_advertisement_address(uint8_t * addr_type, bd_addr_t * addr){
508     *addr_type = hci_stack->adv_addr_type;
509     if (hci_stack->adv_addr_type){
510         memcpy(addr, hci_stack->adv_address, 6);
511     } else {
512         memcpy(addr, hci_stack->local_bd_addr, 6);
513     }
514 }
515 
516 static void le_handle_advertisement_report(uint8_t *packet, int size){
517     int num_reports = packet[3];
518     int i;
519     int total_data_length = 0;
520     int data_offset = 0;
521 
522     for (i=0; i<num_reports;i++){
523         total_data_length += packet[4+num_reports*8+i];
524     }
525 
526     for (i=0; i<num_reports;i++){
527         int pos = 0;
528         uint8_t data_length = packet[4+num_reports*8+i];
529         uint8_t event_size = 10 + data_length;
530         uint8_t event[2 + event_size ];
531         event[pos++] = GAP_LE_ADVERTISING_REPORT;
532         event[pos++] = event_size;
533         event[pos++] = packet[4+i]; // event_type;
534         event[pos++] = packet[4+num_reports+i]; // address_type;
535         bt_flip_addr(&event[pos], &packet[4+num_reports*2+i*6]); // bt address
536         pos += 6;
537         event[pos++] = packet[4+num_reports*9+total_data_length + i];
538         event[pos++] = data_length;
539         memcpy(&packet[4+num_reports*9+data_offset], &event[pos], data_length);
540         data_offset += data_length;
541         pos += data_length;
542         hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
543     }
544 }
545 
546 // avoid huge local variables
547 #ifndef EMBEDDED
548 static device_name_t device_name;
549 #endif
550 static void event_handler(uint8_t *packet, int size){
551 
552     uint16_t event_length = packet[1];
553 
554     // assert packet is complete
555     if (size != event_length + 2){
556         log_error("hci.c: event_handler called with event packet of wrong size %u, expected %u => dropping packet", size, event_length + 2);
557         return;
558     }
559 
560     bd_addr_t addr;
561     bd_addr_type_t addr_type;
562     uint8_t link_type;
563     hci_con_handle_t handle;
564     hci_connection_t * conn;
565     int i;
566 
567     // printf("HCI:EVENT:%02x\n", packet[0]);
568 
569     switch (packet[0]) {
570 
571         case HCI_EVENT_COMMAND_COMPLETE:
572             // get num cmd packets
573             // log_info("HCI_EVENT_COMMAND_COMPLETE cmds old %u - new %u\n", hci_stack->num_cmd_packets, packet[2]);
574             hci_stack->num_cmd_packets = packet[2];
575 
576             if (COMMAND_COMPLETE_EVENT(packet, hci_read_buffer_size)){
577                 // from offset 5
578                 // status
579                 // "The HC_ACL_Data_Packet_Length return parameter will be used to determine the size of the L2CAP segments contained in ACL Data Packets"
580                 hci_stack->acl_data_packet_length = READ_BT_16(packet, 6);
581                 // ignore: SCO data packet len (8)
582                 hci_stack->total_num_acl_packets  = packet[9];
583                 // ignore: total num SCO packets
584                 if (hci_stack->state == HCI_STATE_INITIALIZING){
585                     // determine usable ACL payload size
586                     if (HCI_ACL_PAYLOAD_SIZE < hci_stack->acl_data_packet_length){
587                         hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
588                     }
589                     log_info("hci_read_buffer_size: used size %u, count %u\n",
590                              hci_stack->acl_data_packet_length, hci_stack->total_num_acl_packets);
591                 }
592             }
593 #ifdef HAVE_BLE
594             if (COMMAND_COMPLETE_EVENT(packet, hci_le_read_buffer_size)){
595                 hci_stack->le_data_packet_length = READ_BT_16(packet, 6);
596                 hci_stack->total_num_le_packets  = packet[8];
597                 log_info("hci_le_read_buffer_size: size %u, count %u\n", hci_stack->le_data_packet_length, hci_stack->total_num_le_packets);
598             }
599 #endif
600             // Dump local address
601             if (COMMAND_COMPLETE_EVENT(packet, hci_read_bd_addr)) {
602                 bt_flip_addr(hci_stack->local_bd_addr, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE + 1]);
603                 log_info("Local Address, Status: 0x%02x: Addr: %s\n",
604                     packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE], bd_addr_to_str(hci_stack->local_bd_addr));
605             }
606             if (COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
607                 hci_emit_discoverable_enabled(hci_stack->discoverable);
608             }
609             // Note: HCI init checks
610             if (COMMAND_COMPLETE_EVENT(packet, hci_read_local_supported_features)){
611                 memcpy(hci_stack->local_supported_features, &packet[OFFSET_OF_DATA_IN_COMMAND_COMPLETE+1], 8);
612                 log_info("Local Supported Features: 0x%02x%02x%02x%02x%02x%02x%02x%02x",
613                     hci_stack->local_supported_features[0], hci_stack->local_supported_features[1],
614                     hci_stack->local_supported_features[2], hci_stack->local_supported_features[3],
615                     hci_stack->local_supported_features[4], hci_stack->local_supported_features[5],
616                     hci_stack->local_supported_features[6], hci_stack->local_supported_features[7]);
617 
618                 // determine usable ACL packet types based buffer size and supported features
619                 hci_stack->packet_types = hci_acl_packet_types_for_buffer_size_and_local_features(hci_stack->acl_data_packet_length, &hci_stack->local_supported_features[0]);
620                 log_info("packet types %04x", hci_stack->packet_types);
621 
622                 // Classic/LE
623                 log_info("BR/EDR support %u, LE support %u", hci_classic_supported(), hci_le_supported());
624             }
625             break;
626 
627         case HCI_EVENT_COMMAND_STATUS:
628             // get num cmd packets
629             // log_info("HCI_EVENT_COMMAND_STATUS cmds - old %u - new %u\n", hci_stack->num_cmd_packets, packet[3]);
630             hci_stack->num_cmd_packets = packet[3];
631             break;
632 
633         case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS:
634             for (i=0; i<packet[2];i++){
635                 handle = READ_BT_16(packet, 3 + 2*i);
636                 uint16_t num_packets = READ_BT_16(packet, 3 + packet[2]*2 + 2*i);
637                 conn = hci_connection_for_handle(handle);
638                 if (!conn){
639                     log_error("hci_number_completed_packet lists unused con handle %u\n", handle);
640                     continue;
641                 }
642                 conn->num_acl_packets_sent -= num_packets;
643                 // log_info("hci_number_completed_packet %u processed for handle %u, outstanding %u\n", num_packets, handle, conn->num_acl_packets_sent);
644             }
645             break;
646 
647         case HCI_EVENT_CONNECTION_REQUEST:
648             bt_flip_addr(addr, &packet[2]);
649             // TODO: eval COD 8-10
650             link_type = packet[11];
651             log_info("Connection_incoming: %s, type %u\n", bd_addr_to_str(addr), link_type);
652             if (link_type == 1) { // ACL
653                 conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
654                 if (!conn) {
655                     conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
656                 }
657                 if (!conn) {
658                     // CONNECTION REJECTED DUE TO LIMITED RESOURCES (0X0D)
659                     hci_stack->decline_reason = 0x0d;
660                     BD_ADDR_COPY(hci_stack->decline_addr, addr);
661                     break;
662                 }
663                 conn->state = RECEIVED_CONNECTION_REQUEST;
664                 hci_run();
665             } else {
666                 // SYNCHRONOUS CONNECTION LIMIT TO A DEVICE EXCEEDED (0X0A)
667                 hci_stack->decline_reason = 0x0a;
668                 BD_ADDR_COPY(hci_stack->decline_addr, addr);
669             }
670             break;
671 
672         case HCI_EVENT_CONNECTION_COMPLETE:
673             // Connection management
674             bt_flip_addr(addr, &packet[5]);
675             log_info("Connection_complete (status=%u) %s\n", packet[2], bd_addr_to_str(addr));
676             addr_type = BD_ADDR_TYPE_CLASSIC;
677             conn = hci_connection_for_bd_addr_and_type(&addr, addr_type);
678             if (conn) {
679                 if (!packet[2]){
680                     conn->state = OPEN;
681                     conn->con_handle = READ_BT_16(packet, 3);
682                     conn->bonding_flags |= BONDING_REQUEST_REMOTE_FEATURES;
683 
684                     // restart timer
685                     run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
686                     run_loop_add_timer(&conn->timeout);
687 
688                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
689 
690                     hci_emit_nr_connections_changed();
691                 } else {
692                     // notify client if dedicated bonding
693                     if (conn->bonding_flags & BONDING_DEDICATED){
694                         hci_emit_dedicated_bonding_result(conn, packet[2]);
695                     }
696 
697                     // connection failed, remove entry
698                     linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
699                     btstack_memory_hci_connection_free( conn );
700 
701                     // if authentication error, also delete link key
702                     if (packet[2] == 0x05) {
703                         hci_drop_link_key_for_bd_addr(&addr);
704                     }
705                 }
706             }
707             break;
708 
709         case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE:
710             handle = READ_BT_16(packet, 3);
711             conn = hci_connection_for_handle(handle);
712             if (!conn) break;
713             if (!packet[2]){
714                 uint8_t * features = &packet[5];
715                 if (features[6] & (1 << 3)){
716                     conn->bonding_flags |= BONDING_REMOTE_SUPPORTS_SSP;
717                 }
718             }
719             conn->bonding_flags |= BONDING_RECEIVED_REMOTE_FEATURES;
720             log_info("HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE, bonding flags %x", conn->bonding_flags);
721             if (conn->bonding_flags & BONDING_DEDICATED){
722                 conn->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
723             }
724             break;
725 
726         case HCI_EVENT_LINK_KEY_REQUEST:
727             log_info("HCI_EVENT_LINK_KEY_REQUEST\n");
728             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_LINK_KEY_REQUEST);
729             // non-bondable mode: link key negative reply will be sent by HANDLE_LINK_KEY_REQUEST
730             if (hci_stack->bondable && !hci_stack->remote_device_db) break;
731             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], HANDLE_LINK_KEY_REQUEST);
732             hci_run();
733             // request handled by hci_run() as HANDLE_LINK_KEY_REQUEST gets set
734             return;
735 
736         case HCI_EVENT_LINK_KEY_NOTIFICATION: {
737             bt_flip_addr(addr, &packet[2]);
738             conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
739             if (!conn) break;
740             conn->authentication_flags |= RECV_LINK_KEY_NOTIFICATION;
741             link_key_type_t link_key_type = (link_key_type_t)packet[24];
742             // Change Connection Encryption keeps link key type
743             if (link_key_type != CHANGED_COMBINATION_KEY){
744                 conn->link_key_type = link_key_type;
745             }
746             if (!hci_stack->remote_device_db) break;
747             hci_stack->remote_device_db->put_link_key(&addr, (link_key_t *) &packet[8], conn->link_key_type);
748             // still forward event to allow dismiss of pairing dialog
749             break;
750         }
751 
752         case HCI_EVENT_PIN_CODE_REQUEST:
753             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], LEGACY_PAIRING_ACTIVE);
754             // non-bondable mode: pin code negative reply will be sent
755             if (!hci_stack->bondable){
756                 hci_add_connection_flags_for_flipped_bd_addr(&packet[2], DENY_PIN_CODE_REQUEST);
757                 hci_run();
758                 return;
759             }
760             // PIN CODE REQUEST means the link key request didn't succee -> delete stored link key
761             if (!hci_stack->remote_device_db) break;
762             bt_flip_addr(addr, &packet[2]);
763             hci_stack->remote_device_db->delete_link_key(&addr);
764             break;
765 
766         case HCI_EVENT_IO_CAPABILITY_REQUEST:
767             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], RECV_IO_CAPABILITIES_REQUEST);
768             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_IO_CAPABILITIES_REPLY);
769             break;
770 
771         case HCI_EVENT_USER_CONFIRMATION_REQUEST:
772             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
773             if (!hci_stack->ssp_auto_accept) break;
774             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_CONFIRM_REPLY);
775             break;
776 
777         case HCI_EVENT_USER_PASSKEY_REQUEST:
778             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SSP_PAIRING_ACTIVE);
779             if (!hci_stack->ssp_auto_accept) break;
780             hci_add_connection_flags_for_flipped_bd_addr(&packet[2], SEND_USER_PASSKEY_REPLY);
781             break;
782 
783         case HCI_EVENT_ENCRYPTION_CHANGE:
784             handle = READ_BT_16(packet, 3);
785             conn = hci_connection_for_handle(handle);
786             if (!conn) break;
787             if (packet[2] == 0) {
788                 if (packet[5]){
789                     conn->authentication_flags |= CONNECTION_ENCRYPTED;
790                 } else {
791                     conn->authentication_flags &= ~CONNECTION_ENCRYPTED;
792                 }
793             }
794             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
795             break;
796 
797         case HCI_EVENT_AUTHENTICATION_COMPLETE_EVENT:
798             handle = READ_BT_16(packet, 3);
799             conn = hci_connection_for_handle(handle);
800             if (!conn) break;
801 
802             // dedicated bonding: send result and disconnect
803             if (conn->bonding_flags & BONDING_DEDICATED){
804                 conn->bonding_flags &= ~BONDING_DEDICATED;
805                 hci_emit_dedicated_bonding_result( conn, packet[2]);
806                 conn->bonding_flags |= BONDING_DISCONNECT_DEDICATED_DONE;
807                 break;
808             }
809 
810             if (packet[2] == 0 && gap_security_level_for_link_key_type(conn->link_key_type) >= conn->requested_security_level){
811                 // link key sufficient for requested security
812                 conn->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
813                 break;
814             }
815             // not enough
816             hci_emit_security_level(handle, gap_security_level_for_connection(conn));
817             break;
818 
819 #ifndef EMBEDDED
820         case HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE:
821             if (!hci_stack->remote_device_db) break;
822             if (packet[2]) break; // status not ok
823             bt_flip_addr(addr, &packet[3]);
824             // fix for invalid remote names - terminate on 0xff
825             for (i=0; i<248;i++){
826                 if (packet[9+i] == 0xff){
827                     packet[9+i] = 0;
828                     break;
829                 }
830             }
831             memset(&device_name, 0, sizeof(device_name_t));
832             strncpy((char*) device_name, (char*) &packet[9], 248);
833             hci_stack->remote_device_db->put_name(&addr, &device_name);
834             break;
835 
836         case HCI_EVENT_INQUIRY_RESULT:
837         case HCI_EVENT_INQUIRY_RESULT_WITH_RSSI:
838             if (!hci_stack->remote_device_db) break;
839             // first send inq result packet
840             hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
841             // then send cached remote names
842             for (i=0; i<packet[2];i++){
843                 bt_flip_addr(addr, &packet[3+i*6]);
844                 if (hci_stack->remote_device_db->get_name(&addr, &device_name)){
845                     hci_emit_remote_name_cached(&addr, &device_name);
846                 }
847             }
848             return;
849 #endif
850 
851         case HCI_EVENT_DISCONNECTION_COMPLETE:
852             if (!packet[2]){
853                 handle = READ_BT_16(packet, 3);
854                 hci_connection_t * conn = hci_connection_for_handle(handle);
855                 if (conn) {
856                     hci_shutdown_connection(conn);
857                 }
858             }
859             break;
860 
861         case HCI_EVENT_HARDWARE_ERROR:
862             if(hci_stack->control && hci_stack->control->hw_error){
863                 (*hci_stack->control->hw_error)();
864             }
865             break;
866 
867         case DAEMON_EVENT_HCI_PACKET_SENT:
868             // free packet buffer for asynchronous transport
869             if (hci_transport_synchronous()) break;
870             hci_stack->hci_packet_buffer_reserved = 0;
871             break;
872 
873 #ifdef HAVE_BLE
874         case HCI_EVENT_LE_META:
875             switch (packet[2]){
876                 case HCI_SUBEVENT_LE_ADVERTISING_REPORT:
877                     if (hci_stack->le_scanning_state != LE_SCANNING) break;
878                     le_handle_advertisement_report(packet, size);
879                     break;
880                 case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
881                     // Connection management
882                     bt_flip_addr(addr, &packet[8]);
883                     addr_type = (bd_addr_type_t)packet[7];
884                     log_info("LE Connection_complete (status=%u) type %u, %s\n", packet[3], addr_type, bd_addr_to_str(addr));
885                     // LE connections are auto-accepted, so just create a connection if there isn't one already
886                     conn = hci_connection_for_bd_addr_and_type(&addr, addr_type);
887                     if (packet[3]){
888                         if (conn){
889                             // outgoing connection failed, remove entry
890                             linked_list_remove(&hci_stack->connections, (linked_item_t *) conn);
891                             btstack_memory_hci_connection_free( conn );
892 
893                         }
894                         // if authentication error, also delete link key
895                         if (packet[3] == 0x05) {
896                             hci_drop_link_key_for_bd_addr(&addr);
897                         }
898                         break;
899                     }
900                     if (!conn){
901                         conn = create_connection_for_bd_addr_and_type(addr, addr_type);
902                     }
903                     if (!conn){
904                         // no memory
905                         break;
906                     }
907 
908                     conn->state = OPEN;
909                     conn->con_handle = READ_BT_16(packet, 4);
910 
911                     // TODO: store - role, peer address type, conn_interval, conn_latency, supervision timeout, master clock
912 
913                     // restart timer
914                     // run_loop_set_timer(&conn->timeout, HCI_CONNECTION_TIMEOUT_MS);
915                     // run_loop_add_timer(&conn->timeout);
916 
917                     log_info("New connection: handle %u, %s\n", conn->con_handle, bd_addr_to_str(conn->address));
918 
919                     hci_emit_nr_connections_changed();
920                     break;
921 
922             // printf("LE buffer size: %u, count %u\n", READ_BT_16(packet,6), packet[8]);
923 
924                 default:
925                     break;
926             }
927             break;
928 #endif
929 
930         default:
931             break;
932     }
933 
934     // handle BT initialization
935     if (hci_stack->state == HCI_STATE_INITIALIZING){
936         if (hci_stack->substate % 2){
937             // odd: waiting for event
938             if (packet[0] == HCI_EVENT_COMMAND_COMPLETE || packet[0] == HCI_EVENT_COMMAND_STATUS){
939                 // wait for explicit COMMAND COMPLETE on RESET
940                 if (hci_stack->substate > 1 || COMMAND_COMPLETE_EVENT(packet, hci_reset)) {
941                     hci_stack->substate++;
942                 }
943             }
944         }
945     }
946 
947     // help with BT sleep
948     if (hci_stack->state == HCI_STATE_FALLING_ASLEEP
949         && hci_stack->substate == 1
950         && COMMAND_COMPLETE_EVENT(packet, hci_write_scan_enable)){
951         hci_stack->substate++;
952     }
953 
954     hci_stack->packet_handler(HCI_EVENT_PACKET, packet, size);
955 
956 	// execute main loop
957 	hci_run();
958 }
959 
960 static void packet_handler(uint8_t packet_type, uint8_t *packet, uint16_t size){
961     switch (packet_type) {
962         case HCI_EVENT_PACKET:
963             event_handler(packet, size);
964             break;
965         case HCI_ACL_DATA_PACKET:
966             acl_handler(packet, size);
967             break;
968         default:
969             break;
970     }
971 }
972 
973 /** Register HCI packet handlers */
974 void hci_register_packet_handler(void (*handler)(uint8_t packet_type, uint8_t *packet, uint16_t size)){
975     hci_stack->packet_handler = handler;
976 }
977 
978 void hci_init(hci_transport_t *transport, void *config, bt_control_t *control, remote_device_db_t const* remote_device_db){
979 
980 #ifdef HAVE_MALLOC
981     if (!hci_stack) {
982         hci_stack = (hci_stack_t*) malloc(sizeof(hci_stack_t));
983     }
984 #else
985     hci_stack = &hci_stack_static;
986 #endif
987     memset(hci_stack, 0, sizeof(hci_stack_t));
988 
989     // reference to use transport layer implementation
990     hci_stack->hci_transport = transport;
991 
992     // references to used control implementation
993     hci_stack->control = control;
994 
995     // reference to used config
996     hci_stack->config = config;
997 
998     // no connections yet
999     hci_stack->connections = NULL;
1000     hci_stack->discoverable = 0;
1001     hci_stack->connectable = 0;
1002     hci_stack->bondable = 1;
1003 
1004     // no pending cmds
1005     hci_stack->decline_reason = 0;
1006     hci_stack->new_scan_enable_value = 0xff;
1007 
1008     // higher level handler
1009     hci_stack->packet_handler = dummy_handler;
1010 
1011     // store and open remote device db
1012     hci_stack->remote_device_db = remote_device_db;
1013     if (hci_stack->remote_device_db) {
1014         hci_stack->remote_device_db->open();
1015     }
1016 
1017     // max acl payload size defined in config.h
1018     hci_stack->acl_data_packet_length = HCI_ACL_PAYLOAD_SIZE;
1019 
1020     // register packet handlers with transport
1021     transport->register_packet_handler(&packet_handler);
1022 
1023     hci_stack->state = HCI_STATE_OFF;
1024 
1025     // class of device
1026     hci_stack->class_of_device = 0x007a020c; // Smartphone
1027 
1028     // Secure Simple Pairing default: enable, no I/O capabilities, general bonding, mitm not required, auto accept
1029     hci_stack->ssp_enable = 1;
1030     hci_stack->ssp_io_capability = SSP_IO_CAPABILITY_NO_INPUT_NO_OUTPUT;
1031     hci_stack->ssp_authentication_requirement = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_GENERAL_BONDING;
1032     hci_stack->ssp_auto_accept = 1;
1033 
1034     // LE
1035     hci_stack->adv_addr_type = 0;
1036     memset(hci_stack->adv_address, 0, 6);
1037     hci_stack->le_scanning_state = LE_SCAN_IDLE;
1038 }
1039 
1040 void hci_close(){
1041     // close remote device db
1042     if (hci_stack->remote_device_db) {
1043         hci_stack->remote_device_db->close();
1044     }
1045     while (hci_stack->connections) {
1046         hci_shutdown_connection((hci_connection_t *) hci_stack->connections);
1047     }
1048     hci_power_control(HCI_POWER_OFF);
1049 
1050 #ifdef HAVE_MALLOC
1051     free(hci_stack);
1052 #endif
1053     hci_stack = NULL;
1054 }
1055 
1056 void hci_set_class_of_device(uint32_t class_of_device){
1057     hci_stack->class_of_device = class_of_device;
1058 }
1059 
1060 void hci_disable_l2cap_timeout_check(){
1061     disable_l2cap_timeouts = 1;
1062 }
1063 // State-Module-Driver overview
1064 // state                    module  low-level
1065 // HCI_STATE_OFF             off      close
1066 // HCI_STATE_INITIALIZING,   on       open
1067 // HCI_STATE_WORKING,        on       open
1068 // HCI_STATE_HALTING,        on       open
1069 // HCI_STATE_SLEEPING,    off/sleep   close
1070 // HCI_STATE_FALLING_ASLEEP  on       open
1071 
1072 static int hci_power_control_on(void){
1073 
1074     // power on
1075     int err = 0;
1076     if (hci_stack->control && hci_stack->control->on){
1077         err = (*hci_stack->control->on)(hci_stack->config);
1078     }
1079     if (err){
1080         log_error( "POWER_ON failed\n");
1081         hci_emit_hci_open_failed();
1082         return err;
1083     }
1084 
1085     // open low-level device
1086     err = hci_stack->hci_transport->open(hci_stack->config);
1087     if (err){
1088         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
1089         if (hci_stack->control && hci_stack->control->off){
1090             (*hci_stack->control->off)(hci_stack->config);
1091         }
1092         hci_emit_hci_open_failed();
1093         return err;
1094     }
1095     return 0;
1096 }
1097 
1098 static void hci_power_control_off(void){
1099 
1100     log_info("hci_power_control_off\n");
1101 
1102     // close low-level device
1103     hci_stack->hci_transport->close(hci_stack->config);
1104 
1105     log_info("hci_power_control_off - hci_transport closed\n");
1106 
1107     // power off
1108     if (hci_stack->control && hci_stack->control->off){
1109         (*hci_stack->control->off)(hci_stack->config);
1110     }
1111 
1112     log_info("hci_power_control_off - control closed\n");
1113 
1114     hci_stack->state = HCI_STATE_OFF;
1115 }
1116 
1117 static void hci_power_control_sleep(void){
1118 
1119     log_info("hci_power_control_sleep\n");
1120 
1121 #if 0
1122     // don't close serial port during sleep
1123 
1124     // close low-level device
1125     hci_stack->hci_transport->close(hci_stack->config);
1126 #endif
1127 
1128     // sleep mode
1129     if (hci_stack->control && hci_stack->control->sleep){
1130         (*hci_stack->control->sleep)(hci_stack->config);
1131     }
1132 
1133     hci_stack->state = HCI_STATE_SLEEPING;
1134 }
1135 
1136 static int hci_power_control_wake(void){
1137 
1138     log_info("hci_power_control_wake\n");
1139 
1140     // wake on
1141     if (hci_stack->control && hci_stack->control->wake){
1142         (*hci_stack->control->wake)(hci_stack->config);
1143     }
1144 
1145 #if 0
1146     // open low-level device
1147     int err = hci_stack->hci_transport->open(hci_stack->config);
1148     if (err){
1149         log_error( "HCI_INIT failed, turning Bluetooth off again\n");
1150         if (hci_stack->control && hci_stack->control->off){
1151             (*hci_stack->control->off)(hci_stack->config);
1152         }
1153         hci_emit_hci_open_failed();
1154         return err;
1155     }
1156 #endif
1157 
1158     return 0;
1159 }
1160 
1161 
1162 int hci_power_control(HCI_POWER_MODE power_mode){
1163 
1164     log_info("hci_power_control: %u, current mode %u\n", power_mode, hci_stack->state);
1165 
1166     int err = 0;
1167     switch (hci_stack->state){
1168 
1169         case HCI_STATE_OFF:
1170             switch (power_mode){
1171                 case HCI_POWER_ON:
1172                     err = hci_power_control_on();
1173                     if (err) return err;
1174                     // set up state machine
1175                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1176                     hci_stack->state = HCI_STATE_INITIALIZING;
1177                     hci_stack->substate = 0;
1178                     break;
1179                 case HCI_POWER_OFF:
1180                     // do nothing
1181                     break;
1182                 case HCI_POWER_SLEEP:
1183                     // do nothing (with SLEEP == OFF)
1184                     break;
1185             }
1186             break;
1187 
1188         case HCI_STATE_INITIALIZING:
1189             switch (power_mode){
1190                 case HCI_POWER_ON:
1191                     // do nothing
1192                     break;
1193                 case HCI_POWER_OFF:
1194                     // no connections yet, just turn it off
1195                     hci_power_control_off();
1196                     break;
1197                 case HCI_POWER_SLEEP:
1198                     // no connections yet, just turn it off
1199                     hci_power_control_sleep();
1200                     break;
1201             }
1202             break;
1203 
1204         case HCI_STATE_WORKING:
1205             switch (power_mode){
1206                 case HCI_POWER_ON:
1207                     // do nothing
1208                     break;
1209                 case HCI_POWER_OFF:
1210                     // see hci_run
1211                     hci_stack->state = HCI_STATE_HALTING;
1212                     break;
1213                 case HCI_POWER_SLEEP:
1214                     // see hci_run
1215                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
1216                     hci_stack->substate = 0;
1217                     break;
1218             }
1219             break;
1220 
1221         case HCI_STATE_HALTING:
1222             switch (power_mode){
1223                 case HCI_POWER_ON:
1224                     // set up state machine
1225                     hci_stack->state = HCI_STATE_INITIALIZING;
1226                     hci_stack->substate = 0;
1227                     break;
1228                 case HCI_POWER_OFF:
1229                     // do nothing
1230                     break;
1231                 case HCI_POWER_SLEEP:
1232                     // see hci_run
1233                     hci_stack->state = HCI_STATE_FALLING_ASLEEP;
1234                     hci_stack->substate = 0;
1235                     break;
1236             }
1237             break;
1238 
1239         case HCI_STATE_FALLING_ASLEEP:
1240             switch (power_mode){
1241                 case HCI_POWER_ON:
1242 
1243 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1244                     // nothing to do, if H4 supports power management
1245                     if (bt_control_iphone_power_management_enabled()){
1246                         hci_stack->state = HCI_STATE_INITIALIZING;
1247                         hci_stack->substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1248                         break;
1249                     }
1250 #endif
1251                     // set up state machine
1252                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1253                     hci_stack->state = HCI_STATE_INITIALIZING;
1254                     hci_stack->substate = 0;
1255                     break;
1256                 case HCI_POWER_OFF:
1257                     // see hci_run
1258                     hci_stack->state = HCI_STATE_HALTING;
1259                     break;
1260                 case HCI_POWER_SLEEP:
1261                     // do nothing
1262                     break;
1263             }
1264             break;
1265 
1266         case HCI_STATE_SLEEPING:
1267             switch (power_mode){
1268                 case HCI_POWER_ON:
1269 
1270 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1271                     // nothing to do, if H4 supports power management
1272                     if (bt_control_iphone_power_management_enabled()){
1273                         hci_stack->state = HCI_STATE_INITIALIZING;
1274                         hci_stack->substate = HCI_INTIALIZING_SUBSTATE_AFTER_SLEEP;
1275                         hci_update_scan_enable();
1276                         break;
1277                     }
1278 #endif
1279                     err = hci_power_control_wake();
1280                     if (err) return err;
1281                     // set up state machine
1282                     hci_stack->num_cmd_packets = 1; // assume that one cmd can be sent
1283                     hci_stack->state = HCI_STATE_INITIALIZING;
1284                     hci_stack->substate = 0;
1285                     break;
1286                 case HCI_POWER_OFF:
1287                     hci_stack->state = HCI_STATE_HALTING;
1288                     break;
1289                 case HCI_POWER_SLEEP:
1290                     // do nothing
1291                     break;
1292             }
1293             break;
1294     }
1295 
1296     // create internal event
1297 	hci_emit_state();
1298 
1299 	// trigger next/first action
1300 	hci_run();
1301 
1302     return 0;
1303 }
1304 
1305 static void hci_update_scan_enable(void){
1306     // 2 = page scan, 1 = inq scan
1307     hci_stack->new_scan_enable_value  = hci_stack->connectable << 1 | hci_stack->discoverable;
1308     hci_run();
1309 }
1310 
1311 void hci_discoverable_control(uint8_t enable){
1312     if (enable) enable = 1; // normalize argument
1313 
1314     if (hci_stack->discoverable == enable){
1315         hci_emit_discoverable_enabled(hci_stack->discoverable);
1316         return;
1317     }
1318 
1319     hci_stack->discoverable = enable;
1320     hci_update_scan_enable();
1321 }
1322 
1323 void hci_connectable_control(uint8_t enable){
1324     if (enable) enable = 1; // normalize argument
1325 
1326     // don't emit event
1327     if (hci_stack->connectable == enable) return;
1328 
1329     hci_stack->connectable = enable;
1330     hci_update_scan_enable();
1331 }
1332 
1333 bd_addr_t * hci_local_bd_addr(void){
1334     return &hci_stack->local_bd_addr;
1335 }
1336 
1337 void hci_run(){
1338 
1339     hci_connection_t * connection;
1340     linked_item_t * it;
1341 
1342     if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1343 
1344     // global/non-connection oriented commands
1345 
1346     // decline incoming connections
1347     if (hci_stack->decline_reason){
1348         uint8_t reason = hci_stack->decline_reason;
1349         hci_stack->decline_reason = 0;
1350         hci_send_cmd(&hci_reject_connection_request, hci_stack->decline_addr, reason);
1351         return;
1352     }
1353 
1354     // send scan enable
1355     if (hci_stack->state == HCI_STATE_WORKING && hci_stack->new_scan_enable_value != 0xff && hci_classic_supported()){
1356         hci_send_cmd(&hci_write_scan_enable, hci_stack->new_scan_enable_value);
1357         hci_stack->new_scan_enable_value = 0xff;
1358         return;
1359     }
1360 
1361     // handle le scan
1362     if (hci_stack->state == HCI_STATE_WORKING){
1363         switch(hci_stack->le_scanning_state){
1364             case LE_START_SCAN:
1365                 hci_stack->le_scanning_state = LE_SCANNING;
1366                 hci_send_cmd(&hci_le_set_scan_enable, 1, 0);
1367                 return;
1368 
1369             case LE_STOP_SCAN:
1370                 hci_stack->le_scanning_state = LE_SCAN_IDLE;
1371                 hci_send_cmd(&hci_le_set_scan_enable, 0, 0);
1372                 return;
1373             default:
1374                 break;
1375         }
1376     }
1377 
1378     // send pending HCI commands
1379     for (it = (linked_item_t *) hci_stack->connections; it ; it = it->next){
1380         connection = (hci_connection_t *) it;
1381 
1382         if (connection->state == SEND_DISCONNECT){
1383             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13); // remote closed connection
1384             connection->state = SENT_DISCONNECT;
1385             return;
1386         }
1387 
1388         if (connection->state == SEND_CREATE_CONNECTION){
1389             log_info("sending hci_create_connection\n");
1390             switch(connection->address_type){
1391                 case BD_ADDR_TYPE_CLASSIC:
1392                     hci_send_cmd(&hci_create_connection, connection->address, hci_usable_acl_packet_types(), 0, 0, 0, 1);
1393                     break;
1394                 default:
1395                     hci_send_cmd(&hci_le_create_connection,
1396                                  1000,      // scan interval: 625 ms
1397                                  1000,      // scan interval: 625 ms
1398                                  0,         // don't use whitelist
1399                                  connection->address_type, // peer address type
1400                                  connection->address,       // peer bd addr
1401                                  0,         // our addr type: public
1402                                  80,        // conn interval min
1403                                  80,        // conn interval max (3200 * 0.625)
1404                                  0,         // conn latency
1405                                  2000,      // supervision timeout
1406                                  0,         // min ce length
1407                                  1000       // max ce length
1408                                  );
1409 
1410                     connection->state = SENT_CREATE_CONNECTION;
1411                     break;
1412             }
1413             return;
1414         }
1415 
1416         if (connection->state == RECEIVED_CONNECTION_REQUEST){
1417             log_info("sending hci_accept_connection_request\n");
1418             connection->state = ACCEPTED_CONNECTION_REQUEST;
1419             hci_send_cmd(&hci_accept_connection_request, connection->address, 1);
1420             return;
1421         }
1422 
1423         if (connection->authentication_flags & HANDLE_LINK_KEY_REQUEST){
1424             log_info("responding to link key request\n");
1425             connectionClearAuthenticationFlags(connection, HANDLE_LINK_KEY_REQUEST);
1426             link_key_t link_key;
1427             link_key_type_t link_key_type;
1428             if ( hci_stack->remote_device_db
1429               && hci_stack->remote_device_db->get_link_key( &connection->address, &link_key, &link_key_type)
1430               && gap_security_level_for_link_key_type(link_key_type) >= connection->requested_security_level){
1431                connection->link_key_type = link_key_type;
1432                hci_send_cmd(&hci_link_key_request_reply, connection->address, &link_key);
1433             } else {
1434                hci_send_cmd(&hci_link_key_request_negative_reply, connection->address);
1435             }
1436             return;
1437         }
1438 
1439         if (connection->authentication_flags & DENY_PIN_CODE_REQUEST){
1440             log_info("denying to pin request\n");
1441             connectionClearAuthenticationFlags(connection, DENY_PIN_CODE_REQUEST);
1442             hci_send_cmd(&hci_pin_code_request_negative_reply, connection->address);
1443             return;
1444         }
1445 
1446         if (connection->authentication_flags & SEND_IO_CAPABILITIES_REPLY){
1447             connectionClearAuthenticationFlags(connection, SEND_IO_CAPABILITIES_REPLY);
1448             log_info("IO Capability Request received, stack bondable %u, io cap %u", hci_stack->bondable, hci_stack->ssp_io_capability);
1449             if (hci_stack->bondable && (hci_stack->ssp_io_capability != SSP_IO_CAPABILITY_UNKNOWN)){
1450                 // tweak authentication requirements
1451                 uint8_t authreq = hci_stack->ssp_authentication_requirement;
1452                 if (connection->bonding_flags & BONDING_DEDICATED){
1453                     authreq = SSP_IO_AUTHREQ_MITM_PROTECTION_NOT_REQUIRED_DEDICATED_BONDING;
1454                 }
1455                 if (gap_mitm_protection_required_for_security_level(connection->requested_security_level)){
1456                     authreq |= 1;
1457                 }
1458                 hci_send_cmd(&hci_io_capability_request_reply, &connection->address, hci_stack->ssp_io_capability, NULL, authreq);
1459             } else {
1460                 hci_send_cmd(&hci_io_capability_request_negative_reply, &connection->address, ERROR_CODE_PAIRING_NOT_ALLOWED);
1461             }
1462             return;
1463         }
1464 
1465         if (connection->authentication_flags & SEND_USER_CONFIRM_REPLY){
1466             connectionClearAuthenticationFlags(connection, SEND_USER_CONFIRM_REPLY);
1467             hci_send_cmd(&hci_user_confirmation_request_reply, &connection->address);
1468             return;
1469         }
1470 
1471         if (connection->authentication_flags & SEND_USER_PASSKEY_REPLY){
1472             connectionClearAuthenticationFlags(connection, SEND_USER_PASSKEY_REPLY);
1473             hci_send_cmd(&hci_user_passkey_request_reply, &connection->address, 000000);
1474             return;
1475         }
1476 
1477         if (connection->bonding_flags & BONDING_REQUEST_REMOTE_FEATURES){
1478             connection->bonding_flags &= ~BONDING_REQUEST_REMOTE_FEATURES;
1479             hci_send_cmd(&hci_read_remote_supported_features_command, connection->con_handle);
1480             return;
1481         }
1482 
1483         if (connection->bonding_flags & BONDING_DISCONNECT_SECURITY_BLOCK){
1484             connection->bonding_flags &= ~BONDING_DISCONNECT_SECURITY_BLOCK;
1485             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x0005);  // authentication failure
1486             return;
1487         }
1488         if (connection->bonding_flags & BONDING_DISCONNECT_DEDICATED_DONE){
1489             connection->bonding_flags &= ~BONDING_DISCONNECT_DEDICATED_DONE;
1490             hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // authentication done
1491             return;
1492         }
1493         if (connection->bonding_flags & BONDING_SEND_AUTHENTICATE_REQUEST){
1494             connection->bonding_flags &= ~BONDING_SEND_AUTHENTICATE_REQUEST;
1495             hci_send_cmd(&hci_authentication_requested, connection->con_handle);
1496             return;
1497         }
1498         if (connection->bonding_flags & BONDING_SEND_ENCRYPTION_REQUEST){
1499             connection->bonding_flags &= ~BONDING_SEND_ENCRYPTION_REQUEST;
1500             hci_send_cmd(&hci_set_connection_encryption, connection->con_handle, 1);
1501             return;
1502         }
1503     }
1504 
1505     switch (hci_stack->state){
1506         case HCI_STATE_INITIALIZING:
1507             // log_info("hci_init: substate %u\n", hci_stack->substate);
1508             if (hci_stack->substate % 2) {
1509                 // odd: waiting for command completion
1510                 return;
1511             }
1512             switch (hci_stack->substate >> 1){
1513                 case 0: // RESET
1514                     hci_send_cmd(&hci_reset);
1515 
1516                     if (hci_stack->config == 0 || ((hci_uart_config_t *)hci_stack->config)->baudrate_main == 0){
1517                         // skip baud change
1518                         hci_stack->substate = 4; // >> 1 = 2
1519                     }
1520                     break;
1521                 case 1: // SEND BAUD CHANGE
1522                     hci_stack->control->baudrate_cmd(hci_stack->config, ((hci_uart_config_t *)hci_stack->config)->baudrate_main, hci_stack->hci_packet_buffer);
1523                     hci_send_cmd_packet(hci_stack->hci_packet_buffer, 3 + hci_stack->hci_packet_buffer[2]);
1524                     break;
1525                 case 2: // LOCAL BAUD CHANGE
1526                     hci_stack->hci_transport->set_baudrate(((hci_uart_config_t *)hci_stack->config)->baudrate_main);
1527                     hci_stack->substate += 2;
1528                     // break missing here for fall through
1529 
1530                 case 3:
1531                     // Custom initialization
1532                     if (hci_stack->control && hci_stack->control->next_cmd){
1533                         int valid_cmd = (*hci_stack->control->next_cmd)(hci_stack->config, hci_stack->hci_packet_buffer);
1534                         if (valid_cmd){
1535                             int size = 3 + hci_stack->hci_packet_buffer[2];
1536                             hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, hci_stack->hci_packet_buffer, size);
1537                             hci_stack->substate = 4; // more init commands
1538                             break;
1539                         }
1540                         log_info("hci_run: init script done\n\r");
1541                     }
1542                     // otherwise continue
1543 					hci_send_cmd(&hci_read_bd_addr);
1544 					break;
1545 				case 4:
1546 					hci_send_cmd(&hci_read_buffer_size);
1547 					break;
1548                 case 5:
1549                     hci_send_cmd(&hci_read_local_supported_features);
1550                     break;
1551                 case 6:
1552                     if (hci_le_supported()){
1553                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x3FFFFFFF);
1554                     } else {
1555                         // Kensington Bluetoot 2.1 USB Dongle (CSR Chipset) returns an error for 0xffff...
1556                         hci_send_cmd(&hci_set_event_mask,0xffffffff, 0x1FFFFFFF);
1557                     }
1558 
1559                     // skip Classic init commands for LE only chipsets
1560                     if (!hci_classic_supported()){
1561                         if (hci_le_supported()){
1562                             hci_stack->substate = 11 << 1;    // skip all classic command
1563                         } else {
1564                             log_error("Neither BR/EDR nor LE supported");
1565                             hci_stack->substate = 13 << 1;    // skip all
1566                         }
1567                     }
1568                     break;
1569                 case 7:
1570                     if (hci_ssp_supported()){
1571                         hci_send_cmd(&hci_write_simple_pairing_mode, hci_stack->ssp_enable);
1572                         break;
1573                     }
1574                     hci_stack->substate += 2;
1575                     // break missing here for fall through
1576 
1577                 case 8:
1578                     // ca. 15 sec
1579                     hci_send_cmd(&hci_write_page_timeout, 0x6000);
1580                     break;
1581                 case 9:
1582                     hci_send_cmd(&hci_write_class_of_device, hci_stack->class_of_device);
1583                     break;
1584                 case 10:
1585                     if (hci_stack->local_name){
1586                         hci_send_cmd(&hci_write_local_name, hci_stack->local_name);
1587                     } else {
1588                         char hostname[30];
1589 #ifdef EMBEDDED
1590                         // BTstack-11:22:33:44:55:66
1591                         strcpy(hostname, "BTstack ");
1592                         strcat(hostname, bd_addr_to_str(hci_stack->local_bd_addr));
1593                         printf("---> Name %s\n", hostname);
1594 #else
1595                         // hostname for POSIX systems
1596                         gethostname(hostname, 30);
1597                         hostname[29] = '\0';
1598 #endif
1599                         hci_send_cmd(&hci_write_local_name, hostname);
1600                     }
1601                     break;
1602                 case 11:
1603 					hci_send_cmd(&hci_write_scan_enable, (hci_stack->connectable << 1) | hci_stack->discoverable); // page scan
1604                     if (!hci_le_supported()){
1605                         // SKIP LE init for Classic only configuration
1606                         hci_stack->substate = 13 << 1;
1607                     }
1608 					break;
1609 
1610 #ifdef HAVE_BLE
1611                 // LE INIT
1612                 case 12:
1613                     hci_send_cmd(&hci_le_read_buffer_size);
1614                     break;
1615                 case 13:
1616                     // LE Supported Host = 1, Simultaneous Host = 0
1617                     hci_send_cmd(&hci_write_le_host_supported, 1, 0);
1618                     break;
1619 #endif
1620 
1621                 // DONE
1622                 case 14:
1623                     // done.
1624                     hci_stack->state = HCI_STATE_WORKING;
1625                     hci_emit_state();
1626                     break;
1627                 default:
1628                     break;
1629             }
1630             hci_stack->substate++;
1631             break;
1632 
1633         case HCI_STATE_HALTING:
1634 
1635             log_info("HCI_STATE_HALTING\n");
1636             // close all open connections
1637             connection =  (hci_connection_t *) hci_stack->connections;
1638             if (connection){
1639 
1640                 // send disconnect
1641                 if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1642 
1643                 log_info("HCI_STATE_HALTING, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1644                 hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1645 
1646                 // send disconnected event right away - causes higher layer connections to get closed, too.
1647                 hci_shutdown_connection(connection);
1648                 return;
1649             }
1650             log_info("HCI_STATE_HALTING, calling off\n");
1651 
1652             // switch mode
1653             hci_power_control_off();
1654 
1655             log_info("HCI_STATE_HALTING, emitting state\n");
1656             hci_emit_state();
1657             log_info("HCI_STATE_HALTING, done\n");
1658             break;
1659 
1660         case HCI_STATE_FALLING_ASLEEP:
1661             switch(hci_stack->substate) {
1662                 case 0:
1663                     log_info("HCI_STATE_FALLING_ASLEEP\n");
1664                     // close all open connections
1665                     connection =  (hci_connection_t *) hci_stack->connections;
1666 
1667 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1668                     // don't close connections, if H4 supports power management
1669                     if (bt_control_iphone_power_management_enabled()){
1670                         connection = NULL;
1671                     }
1672 #endif
1673                     if (connection){
1674 
1675                         // send disconnect
1676                         if (!hci_can_send_packet_now(HCI_COMMAND_DATA_PACKET)) return;
1677 
1678                         log_info("HCI_STATE_FALLING_ASLEEP, connection %p, handle %u\n", connection, (uint16_t)connection->con_handle);
1679                         hci_send_cmd(&hci_disconnect, connection->con_handle, 0x13);  // remote closed connection
1680 
1681                         // send disconnected event right away - causes higher layer connections to get closed, too.
1682                         hci_shutdown_connection(connection);
1683                         return;
1684                     }
1685 
1686                     if (hci_classic_supported()){
1687                         // disable page and inquiry scan
1688                         if (!hci_can_send_packet_now_using_packet_buffer(HCI_COMMAND_DATA_PACKET)) return;
1689 
1690                         log_info("HCI_STATE_HALTING, disabling inq scans\n");
1691                         hci_send_cmd(&hci_write_scan_enable, hci_stack->connectable << 1); // drop inquiry scan but keep page scan
1692 
1693                         // continue in next sub state
1694                         hci_stack->substate++;
1695                         break;
1696                     }
1697                     // fall through for ble-only chips
1698 
1699                 case 2:
1700                     log_info("HCI_STATE_HALTING, calling sleep\n");
1701 #if defined(USE_POWERMANAGEMENT) && defined(USE_BLUETOOL)
1702                     // don't actually go to sleep, if H4 supports power management
1703                     if (bt_control_iphone_power_management_enabled()){
1704                         // SLEEP MODE reached
1705                         hci_stack->state = HCI_STATE_SLEEPING;
1706                         hci_emit_state();
1707                         break;
1708                     }
1709 #endif
1710                     // switch mode
1711                     hci_power_control_sleep();  // changes hci_stack->state to SLEEP
1712                     hci_emit_state();
1713                     break;
1714 
1715                 default:
1716                     break;
1717             }
1718             break;
1719 
1720         default:
1721             break;
1722     }
1723 }
1724 
1725 int hci_send_cmd_packet(uint8_t *packet, int size){
1726     bd_addr_t addr;
1727     hci_connection_t * conn;
1728     // house-keeping
1729 
1730     // create_connection?
1731     if (IS_COMMAND(packet, hci_create_connection)){
1732         bt_flip_addr(addr, &packet[3]);
1733         log_info("Create_connection to %s\n", bd_addr_to_str(addr));
1734 
1735         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1736         if (!conn){
1737             conn = create_connection_for_bd_addr_and_type(addr, BD_ADDR_TYPE_CLASSIC);
1738             if (!conn){
1739                 // notify client that alloc failed
1740                 hci_emit_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
1741                 return 0; // don't sent packet to controller
1742             }
1743             conn->state = SEND_CREATE_CONNECTION;
1744         }
1745         log_info("conn state %u", conn->state);
1746         switch (conn->state){
1747             // if connection active exists
1748             case OPEN:
1749                 // and OPEN, emit connection complete command, don't send to controller
1750                 hci_emit_connection_complete(conn, 0);
1751                 return 0;
1752             case SEND_CREATE_CONNECTION:
1753                 // connection created by hci, e.g. dedicated bonding
1754                 break;
1755             default:
1756                 // otherwise, just ignore as it is already in the open process
1757                 return 0;
1758         }
1759         conn->state = SENT_CREATE_CONNECTION;
1760     }
1761 
1762     if (IS_COMMAND(packet, hci_link_key_request_reply)){
1763         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_REPLY);
1764     }
1765     if (IS_COMMAND(packet, hci_link_key_request_negative_reply)){
1766         hci_add_connection_flags_for_flipped_bd_addr(&packet[3], SENT_LINK_KEY_NEGATIVE_REQUEST);
1767     }
1768 
1769     if (IS_COMMAND(packet, hci_delete_stored_link_key)){
1770         if (hci_stack->remote_device_db){
1771             bt_flip_addr(addr, &packet[3]);
1772             hci_stack->remote_device_db->delete_link_key(&addr);
1773         }
1774     }
1775 
1776     if (IS_COMMAND(packet, hci_pin_code_request_negative_reply)
1777     ||  IS_COMMAND(packet, hci_pin_code_request_reply)){
1778         bt_flip_addr(addr, &packet[3]);
1779         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1780         if (conn){
1781             connectionClearAuthenticationFlags(conn, LEGACY_PAIRING_ACTIVE);
1782         }
1783     }
1784 
1785     if (IS_COMMAND(packet, hci_user_confirmation_request_negative_reply)
1786     ||  IS_COMMAND(packet, hci_user_confirmation_request_reply)
1787     ||  IS_COMMAND(packet, hci_user_passkey_request_negative_reply)
1788     ||  IS_COMMAND(packet, hci_user_passkey_request_reply)) {
1789         bt_flip_addr(addr, &packet[3]);
1790         conn = hci_connection_for_bd_addr_and_type(&addr, BD_ADDR_TYPE_CLASSIC);
1791         if (conn){
1792             connectionClearAuthenticationFlags(conn, SSP_PAIRING_ACTIVE);
1793         }
1794     }
1795 
1796 #ifdef HAVE_BLE
1797     if (IS_COMMAND(packet, hci_le_set_advertising_parameters)){
1798         hci_stack->adv_addr_type = packet[8];
1799     }
1800     if (IS_COMMAND(packet, hci_le_set_random_address)){
1801         bt_flip_addr(hci_stack->adv_address, &packet[3]);
1802     }
1803 #endif
1804 
1805     hci_stack->num_cmd_packets--;
1806     int err = hci_stack->hci_transport->send_packet(HCI_COMMAND_DATA_PACKET, packet, size);
1807 
1808     // free packet buffer for synchronous transport implementations
1809     if (hci_transport_synchronous() && (packet == hci_stack->hci_packet_buffer)){
1810         hci_stack->hci_packet_buffer_reserved = 0;
1811     }
1812 
1813     return err;
1814 }
1815 
1816 // disconnect because of security block
1817 void hci_disconnect_security_block(hci_con_handle_t con_handle){
1818     hci_connection_t * connection = hci_connection_for_handle(con_handle);
1819     if (!connection) return;
1820     connection->bonding_flags |= BONDING_DISCONNECT_SECURITY_BLOCK;
1821 }
1822 
1823 
1824 // Configure Secure Simple Pairing
1825 
1826 // enable will enable SSP during init
1827 void hci_ssp_set_enable(int enable){
1828     hci_stack->ssp_enable = enable;
1829 }
1830 
1831 int hci_local_ssp_activated(){
1832     return hci_ssp_supported() && hci_stack->ssp_enable;
1833 }
1834 
1835 // if set, BTstack will respond to io capability request using authentication requirement
1836 void hci_ssp_set_io_capability(int io_capability){
1837     hci_stack->ssp_io_capability = io_capability;
1838 }
1839 void hci_ssp_set_authentication_requirement(int authentication_requirement){
1840     hci_stack->ssp_authentication_requirement = authentication_requirement;
1841 }
1842 
1843 // if set, BTstack will confirm a numberic comparion and enter '000000' if requested
1844 void hci_ssp_set_auto_accept(int auto_accept){
1845     hci_stack->ssp_auto_accept = auto_accept;
1846 }
1847 
1848 /**
1849  * pre: numcmds >= 0 - it's allowed to send a command to the controller
1850  */
1851 int hci_send_cmd(const hci_cmd_t *cmd, ...){
1852     va_list argptr;
1853     va_start(argptr, cmd);
1854     uint16_t size = hci_create_cmd_internal(hci_stack->hci_packet_buffer, cmd, argptr);
1855     va_end(argptr);
1856     return hci_send_cmd_packet(hci_stack->hci_packet_buffer, size);
1857 }
1858 
1859 // Create various non-HCI events.
1860 // TODO: generalize, use table similar to hci_create_command
1861 
1862 void hci_emit_state(){
1863     log_info("BTSTACK_EVENT_STATE %u", hci_stack->state);
1864     uint8_t event[3];
1865     event[0] = BTSTACK_EVENT_STATE;
1866     event[1] = sizeof(event) - 2;
1867     event[2] = hci_stack->state;
1868     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1869     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1870 }
1871 
1872 void hci_emit_connection_complete(hci_connection_t *conn, uint8_t status){
1873     uint8_t event[13];
1874     event[0] = HCI_EVENT_CONNECTION_COMPLETE;
1875     event[1] = sizeof(event) - 2;
1876     event[2] = status;
1877     bt_store_16(event, 3, conn->con_handle);
1878     bt_flip_addr(&event[5], conn->address);
1879     event[11] = 1; // ACL connection
1880     event[12] = 0; // encryption disabled
1881     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1882     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1883 }
1884 
1885 void hci_emit_le_connection_complete(hci_connection_t *conn, uint8_t status){
1886     uint8_t event[21];
1887     event[0] = HCI_EVENT_LE_META;
1888     event[1] = sizeof(event) - 2;
1889     event[2] = HCI_SUBEVENT_LE_CONNECTION_COMPLETE;
1890     event[3] = status;
1891     bt_store_16(event, 4, conn->con_handle);
1892     event[6] = 0; // TODO: role
1893     event[7] = conn->address_type;
1894     bt_flip_addr(&event[8], conn->address);
1895     bt_store_16(event, 14, 0); // interval
1896     bt_store_16(event, 16, 0); // latency
1897     bt_store_16(event, 18, 0); // supervision timeout
1898     event[20] = 0; // master clock accuracy
1899     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1900     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1901 }
1902 
1903 void hci_emit_disconnection_complete(uint16_t handle, uint8_t reason){
1904     uint8_t event[6];
1905     event[0] = HCI_EVENT_DISCONNECTION_COMPLETE;
1906     event[1] = sizeof(event) - 2;
1907     event[2] = 0; // status = OK
1908     bt_store_16(event, 3, handle);
1909     event[5] = reason;
1910     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1911     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1912 }
1913 
1914 void hci_emit_l2cap_check_timeout(hci_connection_t *conn){
1915     if (disable_l2cap_timeouts) return;
1916     log_info("L2CAP_EVENT_TIMEOUT_CHECK");
1917     uint8_t event[4];
1918     event[0] = L2CAP_EVENT_TIMEOUT_CHECK;
1919     event[1] = sizeof(event) - 2;
1920     bt_store_16(event, 2, conn->con_handle);
1921     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event));
1922     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1923 }
1924 
1925 void hci_emit_nr_connections_changed(){
1926     log_info("BTSTACK_EVENT_NR_CONNECTIONS_CHANGED %u", nr_hci_connections());
1927     uint8_t event[3];
1928     event[0] = BTSTACK_EVENT_NR_CONNECTIONS_CHANGED;
1929     event[1] = sizeof(event) - 2;
1930     event[2] = nr_hci_connections();
1931     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1932     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1933 }
1934 
1935 void hci_emit_hci_open_failed(){
1936     log_info("BTSTACK_EVENT_POWERON_FAILED");
1937     uint8_t event[2];
1938     event[0] = BTSTACK_EVENT_POWERON_FAILED;
1939     event[1] = sizeof(event) - 2;
1940     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1941     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1942 }
1943 
1944 #ifndef EMBEDDED
1945 void hci_emit_btstack_version() {
1946     log_info("BTSTACK_EVENT_VERSION %u.%u", BTSTACK_MAJOR, BTSTACK_MINOR);
1947     uint8_t event[6];
1948     event[0] = BTSTACK_EVENT_VERSION;
1949     event[1] = sizeof(event) - 2;
1950     event[2] = BTSTACK_MAJOR;
1951     event[3] = BTSTACK_MINOR;
1952     bt_store_16(event, 4, BTSTACK_REVISION);
1953     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1954     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1955 }
1956 #endif
1957 
1958 void hci_emit_system_bluetooth_enabled(uint8_t enabled){
1959     log_info("BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED %u", enabled);
1960     uint8_t event[3];
1961     event[0] = BTSTACK_EVENT_SYSTEM_BLUETOOTH_ENABLED;
1962     event[1] = sizeof(event) - 2;
1963     event[2] = enabled;
1964     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1965     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1966 }
1967 
1968 void hci_emit_remote_name_cached(bd_addr_t *addr, device_name_t *name){
1969     uint8_t event[2+1+6+248+1]; // +1 for \0 in log_info
1970     event[0] = BTSTACK_EVENT_REMOTE_NAME_CACHED;
1971     event[1] = sizeof(event) - 2 - 1;
1972     event[2] = 0;   // just to be compatible with HCI_EVENT_REMOTE_NAME_REQUEST_COMPLETE
1973     bt_flip_addr(&event[3], *addr);
1974     memcpy(&event[9], name, 248);
1975 
1976     event[9+248] = 0;   // assert \0 for log_info
1977     log_info("BTSTACK_EVENT_REMOTE_NAME_CACHED %s = '%s'", bd_addr_to_str(*addr), &event[9]);
1978 
1979     hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)-1);
1980     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event)-1);
1981 }
1982 
1983 void hci_emit_discoverable_enabled(uint8_t enabled){
1984     log_info("BTSTACK_EVENT_DISCOVERABLE_ENABLED %u", enabled);
1985     uint8_t event[3];
1986     event[0] = BTSTACK_EVENT_DISCOVERABLE_ENABLED;
1987     event[1] = sizeof(event) - 2;
1988     event[2] = enabled;
1989     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
1990     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
1991 }
1992 
1993 void hci_emit_security_level(hci_con_handle_t con_handle, gap_security_level_t level){
1994     log_info("hci_emit_security_level %u for handle %x", level, con_handle);
1995     uint8_t event[5];
1996     int pos = 0;
1997     event[pos++] = GAP_SECURITY_LEVEL;
1998     event[pos++] = sizeof(event) - 2;
1999     bt_store_16(event, 2, con_handle);
2000     pos += 2;
2001     event[pos++] = level;
2002     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2003     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2004 }
2005 
2006 void hci_emit_dedicated_bonding_result(hci_connection_t * connection, uint8_t status){
2007     log_info("hci_emit_dedicated_bonding_result %u ", status);
2008     uint8_t event[9];
2009     int pos = 0;
2010     event[pos++] = GAP_DEDICATED_BONDING_COMPLETED;
2011     event[pos++] = sizeof(event) - 2;
2012     event[pos++] = status;
2013     bt_flip_addr( * (bd_addr_t *) &event[pos], connection->address);
2014     pos += 6;
2015     hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event));
2016     hci_stack->packet_handler(HCI_EVENT_PACKET, event, sizeof(event));
2017 }
2018 
2019 // query if remote side supports SSP
2020 int hci_remote_ssp_supported(hci_con_handle_t con_handle){
2021     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2022     if (!connection) return 0;
2023     return (connection->bonding_flags & BONDING_REMOTE_SUPPORTS_SSP) ? 1 : 0;
2024 }
2025 
2026 int hci_ssp_supported_on_both_sides(hci_con_handle_t handle){
2027     return hci_local_ssp_activated() && hci_remote_ssp_supported(handle);
2028 }
2029 
2030 // GAP API
2031 /**
2032  * @bbrief enable/disable bonding. default is enabled
2033  * @praram enabled
2034  */
2035 void gap_set_bondable_mode(int enable){
2036     hci_stack->bondable = enable ? 1 : 0;
2037 }
2038 
2039 /**
2040  * @brief map link keys to security levels
2041  */
2042 gap_security_level_t gap_security_level_for_link_key_type(link_key_type_t link_key_type){
2043     switch (link_key_type){
2044         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P256:
2045             return LEVEL_4;
2046         case COMBINATION_KEY:
2047         case AUTHENTICATED_COMBINATION_KEY_GENERATED_FROM_P192:
2048             return LEVEL_3;
2049         default:
2050             return LEVEL_2;
2051     }
2052 }
2053 
2054 static gap_security_level_t gap_security_level_for_connection(hci_connection_t * connection){
2055     if (!connection) return LEVEL_0;
2056     if ((connection->authentication_flags & CONNECTION_ENCRYPTED) == 0) return LEVEL_0;
2057     return gap_security_level_for_link_key_type(connection->link_key_type);
2058 }
2059 
2060 
2061 int gap_mitm_protection_required_for_security_level(gap_security_level_t level){
2062     printf("gap_mitm_protection_required_for_security_level %u\n", level);
2063     return level > LEVEL_2;
2064 }
2065 
2066 /**
2067  * @brief get current security level
2068  */
2069 gap_security_level_t gap_security_level(hci_con_handle_t con_handle){
2070     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2071     if (!connection) return LEVEL_0;
2072     return gap_security_level_for_connection(connection);
2073 }
2074 
2075 /**
2076  * @brief request connection to device to
2077  * @result GAP_AUTHENTICATION_RESULT
2078  */
2079 void gap_request_security_level(hci_con_handle_t con_handle, gap_security_level_t requested_level){
2080     hci_connection_t * connection = hci_connection_for_handle(con_handle);
2081     if (!connection){
2082         hci_emit_security_level(con_handle, LEVEL_0);
2083         return;
2084     }
2085     gap_security_level_t current_level = gap_security_level(con_handle);
2086     log_info("gap_request_security_level %u, current level %u", requested_level, current_level);
2087     if (current_level >= requested_level){
2088         hci_emit_security_level(con_handle, current_level);
2089         return;
2090     }
2091 
2092     connection->requested_security_level = requested_level;
2093 
2094     // would enabling ecnryption suffice (>= LEVEL_2)?
2095     if (hci_stack->remote_device_db){
2096         link_key_type_t link_key_type;
2097         link_key_t      link_key;
2098         if (hci_stack->remote_device_db->get_link_key( &connection->address, &link_key, &link_key_type)){
2099             if (gap_security_level_for_link_key_type(link_key_type) >= requested_level){
2100                 connection->bonding_flags |= BONDING_SEND_ENCRYPTION_REQUEST;
2101                 return;
2102             }
2103         }
2104     }
2105 
2106     // try to authenticate connection
2107     connection->bonding_flags |= BONDING_SEND_AUTHENTICATE_REQUEST;
2108     hci_run();
2109 }
2110 
2111 /**
2112  * @brief start dedicated bonding with device. disconnect after bonding
2113  * @param device
2114  * @param request MITM protection
2115  * @result GAP_DEDICATED_BONDING_COMPLETE
2116  */
2117 int gap_dedicated_bonding(bd_addr_t device, int mitm_protection_required){
2118 
2119     // create connection state machine
2120     hci_connection_t * connection = create_connection_for_bd_addr_and_type(device, BD_ADDR_TYPE_CLASSIC);
2121 
2122     if (!connection){
2123         return BTSTACK_MEMORY_ALLOC_FAILED;
2124     }
2125 
2126     // delete linkn key
2127     hci_drop_link_key_for_bd_addr( (bd_addr_t *) &device);
2128 
2129     // configure LEVEL_2/3, dedicated bonding
2130     connection->state = SEND_CREATE_CONNECTION;
2131     connection->requested_security_level = mitm_protection_required ? LEVEL_3 : LEVEL_2;
2132     printf("gap_dedicated_bonding, mitm %u -> level %u\n", mitm_protection_required, connection->requested_security_level);
2133     connection->bonding_flags = BONDING_DEDICATED;
2134 
2135     // wait for GAP Security Result and send GAP Dedicated Bonding complete
2136 
2137     // handle: connnection failure (connection complete != ok)
2138     // handle: authentication failure
2139     // handle: disconnect on done
2140 
2141     hci_run();
2142 
2143     return 0;
2144 }
2145 
2146 void gap_set_local_name(const char * local_name){
2147     hci_stack->local_name = local_name;
2148 }
2149 
2150 le_command_status_t le_central_start_scan(){
2151     printf("hci_init: scanning state START_SCAN\n");
2152     hci_stack->le_scanning_state = LE_START_SCAN;
2153     hci_run();
2154     return BLE_PERIPHERAL_OK;
2155 }
2156 
2157 le_command_status_t le_central_stop_scan(){
2158     hci_stack->le_scanning_state = LE_STOP_SCAN;
2159     hci_run();
2160     return BLE_PERIPHERAL_OK;
2161 }
2162 
2163 
2164 le_command_status_t le_central_connect(bd_addr_t * addr, bd_addr_type_t addr_type){
2165     hci_connection_t * conn = hci_connection_for_bd_addr_and_type(addr, addr_type);
2166     if (!conn){
2167         conn = create_connection_for_bd_addr_and_type(*addr, addr_type);
2168         if (!conn){
2169             // notify client that alloc failed
2170             hci_emit_le_connection_complete(conn, BTSTACK_MEMORY_ALLOC_FAILED);
2171             return BLE_PERIPHERAL_NOT_CONNECTED; // don't sent packet to controller
2172         }
2173         conn->state = SEND_CREATE_CONNECTION;
2174         return BLE_PERIPHERAL_OK;
2175     }
2176     conn->state = OPEN;
2177     hci_emit_le_connection_complete(conn, 0);
2178     hci_run();
2179     return BLE_PERIPHERAL_OK;
2180 }
2181 
2182 
2183 le_command_status_t gap_disconnect(hci_con_handle_t handle){
2184     hci_connection_t * conn = hci_connection_for_handle(handle);
2185     if (!conn){
2186         hci_emit_le_connection_complete(conn, 0);
2187         return BLE_PERIPHERAL_OK;
2188     }
2189     conn->state = SEND_DISCONNECT;
2190     hci_run();
2191     return BLE_PERIPHERAL_OK;
2192 }
2193